Groundwater management issues in Southern Africa - An IWRM perspective #
2008

Eberhard Braune email@example.com
Department of Earth Sciences
University of the Western Cape
South Africa

Yongxin Xu
Department of Earth Sciences
University of the Western Cape
South Africa

Groundwater management issues in Southern Africa - An IWRM perspective #
3462008699 # Revised version. Originally presented at the International Confer-ence on Integrated Water Resource Management (IWRM) entitled: Lessons from Implementation in Developing Countries which took place from 10 to 12 March 2008 in Cape Town, South Africa, at the Cape Town International Convention Centre. * To whom all correspondence should be addressed.  +2782 310 8183; fax: +2712 8033 527;groundwatercommunity developmentsustainable utilisation and managementIWRM
In contrast to its strategic role as essential resource to help achieve community development and poverty alleviation in the Southern African Development Community (SADC), groundwater has remained a poorly understood and managed resource. This was the finding of a scoping study regarding the status of groundwater resources management in SADC. The key premise for the assessment was that groundwater resource management must take place within an IWRM framework and the IWRM Toolbox developed by the Global Water Partnership was used as the scope and content for the assessment. The SADC region has well-developed policies for regional development and IWRM, as well as a relatively strong focus on groundwater resources. This article questions whether problems relating to Africa's sustainable utilisation and management of groundwater is a unique groundwater problem or must also be related to the challenges experienced in general with the implementation of an IWRM approach in Africa. A key finding was that groundwater management links to groundwater-dependent sectors like agriculture, rural development, health and environment are not well-established in policy or in practice. Internationally, there is a recognition, that such a, quite common, situation can only be addressed through a long-term process through which viable national, regional and local systems can evolve, within a strategic framework in which these intended relationships between diverse sets of interventions or management approaches and the development goals are brought out. However, such a strategic, multi-stakeholder-driven approach also still remains the major challenge in Africa for IWRM implementation as a whole. Recent continent-wide initiatives, like the development of IWRM and water efficiency plans for each country and multi-stakeholder water dialogue processes, have been taken to address this challenge. It is therefore crucial that groundwater becomes an integral part of these and related initiatives. New AMCOW and SADC initiatives for groundwater provide a major opportunity to achieve this.

Introduction

The Africa Regional Document to the 4 th World Water Forum provides a good summary of the water and development situation (World Water Council, 2006). Water is a key factor in Africa's development. Nonetheless, the African continent has to date used only a small proportion (5%) of its available water resources. The African water crisis, often referred to in international forums, is therefore a lot more complex than continental water availability. Key is the large spatial and temporal variability of resource availability, going with the more arid climate prevalent in about 60% of the African continent and the widespread lack of skilled and experienced human resources to manage the irregular availability of water, e.g. through building balancing storage, transferring water between water-rich and water-poor areas and implementing water conservation and demand management.

There is now a growing perception that local groundwater resources will have to play an increasingly strategic role in Africa, in particular for the most vulnerable and most neglected rural communities (AMCOW, 2008;ECA et al., 2000). Crucial in this regard is that, in sub-Saharan Africa, 300 m. people still have no access to safe water supplies -approximately 80% of these live in rural areas (World Water Council, 2006). The health and socio-economic implications of this situation are enormous in terms of morbidity, mortality and sickness from water and sanitation related diseases. Therefore, significantly increasing the coverage of rural water supply in Africa is fundamental to achieving the Millennium Development Goals (MDGs) The challenge lies not so much in stretching local groundwater resources, but in integrated local development efforts.

In contrast to this strategic role for groundwater, it has remained a poorly understood and managed resource (BGR et al., 2007;FAO, 2003). Pollution of the vital underlying groundwater sources in African cities as well as in many rural communities has reached critical levels (Xu and Usher, 2006). This has become a clear threat to water service delivery and meeting the MDGs on water. The overarching challenge has therefore become the sustainable utilisation of local groundwater resources.

Most African countries have adopted IWRM as their principal approach to water resource management (World Water Council, 2006). This article questions whether problems relating to Africa's sustainable utilisation and management of groundwater resources are unique groundwater problems or should also be related to the challenges experienced in general with the implementation of an IWRM approach in Africa. Findings of a scoping study regarding the state of groundwater resource management in the Southern African Development Community are

IWRM challenges in Africa

The concern and challenge that was posed by Agenda 21 for fresh water resources, and which introduced IWRM thinking worldwide, clearly also holds for groundwater:

''Scarcity and misuse of fresh water pose a threat to development and protection of the environment. Human health and welfare, food security, industrial development, and ecosystems on which they depend are all at risk unless water and land are managed more effectively than they have been in the past'.' (United Nations, 1992) The challenges of sustainable development led to increasing 'integration' requirements, which are well captured in the IWRM definition from the Global Water Partnership:

''IWRM is a process which promotes the coordinated development and management of water, land and related resources in order to maximise the resultant economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystems.''

Integrated management approaches are required that are designed to change the way people view and use the resource. According to Burke and Moench (2000), this involves an appreciation of three effective levels of integration, i.e. integration within the hydrological cycle (the physical processes), integration across river basins and aquifers (spatial integration), and integration across the overall social and economic fabric at national and regional level. Areas requiring more coordinated development and management have also been summarised by the Global Water Partnership (2000) and can all be seen from a groundwater perspective:

• Freshwater and coastal zone management • Land and water management • Surface and groundwater management • Quantity and quality in water resources management • Upstream and downstream water-related interests • Mainstreaming of water resources in socio-economic activities • Cross-sectoral integration in national policy development • Macro-economic effects of water development.

In pursuing IWRM comprehensively, there is a need to recognise some overriding criteria that take account of social, economic and natural conditions (Global Water Partnership, 2000):

• Economic efficiency in water use: Because of the increasing scarcity of water and financial resources, the finite and vulnerable nature of water as a resource, and the increasing demands upon it, water must be used with maximum possible efficiency • Equity: The basic right for all people to have access to water of adequate quantity and quality for the sustenance of human wellbeing must be universally recognised • Environmental and ecological sustainability: The present use of the resource should be managed in a way that does not undermine the life-support system thereby compromising use by future generations of the same resource.

Implementing an IWRM process is a question of getting the 'three pillars' right: moving toward an enabling environment of appropriate policies, strategies and legislation for sustainable water resource development and management; putting in place the institutional framework through which the policies, strategies and legislation can be implemented; and setting up the management instruments required by these institutions to do their job (Global Water Partnership, 2000). In practice, however, integration still focuses largely on the water-supply-and-use-system itself -not the economic and social factors determining water demand or the distribution of pollution (Burke and Moench, 2000). This is particularly the case in river basin management.

The challenges of comprehensive integration can be illustrated through the gradual process towards IWRM in Africa. The African Ministers Council on Water (AMCOW) and many African countries have adopted IWRM as their vision and approach for water resource management (SADC, 2005;World Water Council, 2006). The particular water management challenges that IWRM must address here can best be illustrated by the Africa Water Vision (Economic Commission for Africa et al., 2000):

'An Africa where there is an equitable and sustainable use and management of water resources for poverty alleviation, socio-economic development, regional cooperation, and the environment.'

As part of this vision, Africa has embraced the MDGs, the centrepiece of the global development agenda, intended to reduce significantly by 2015 vicious cycles of global poverty, hunger, disease, illiteracy, environmental degradation and gender inequality. While water is key to each of the development goals, the initial water focus has been on Target 10: Halve by 2015 the proportion of people without sustainable access to safe drinking water and sanitation (UN Millennium Project Task Force on Water and Sanitation, 2005). This has introduced a strong shift all over Africa from a water resource management and sustainability focus to service delivery. This shift brought about a decentralisation of service delivery, and often completely new institutions at national level, separate from the traditional water resource management institutions, to regulate and support this process. These changes have been highly significant for groundwater, because its role in Africa is strongly tied to community water supply (BGR et al., 2007).

Only through renewed political pressures for the water sector to address growth and development comprehensively, is there a new opportunity to realistically work towards IWRM in Africa. This can be illustrated by some proposed key responses of the South African water sector to the 'Water for Growth and Development Strategy' (DWAF, 2008):

• Strengthen sector collaboration between water services and water resource management • Engage with other sectors to ensure good governance • Enhance integrated participatory planning for multiple use water services as part of integrated development plans of local government • Place development benefits of water at core of financial strategies and national development plans.

A key mechanism to help achieve this resulted from the decision at the World Summit on Sustainable Development (

Groundwater's role in Southern Africa

Groundwater occurrence in Southern Africa is characterised by the large variety of geological structures and the climatic differences that condition the regional hydrogeological settings. Groundwater characteristics in the region are well summarised in a recent survey regarding capacity for groundwater management in West and Southern Africa (BGR et al., 2007). According to this report approximately 60 to 65% of the region is covered by crystalline rocks with aquifer systems developed in the weathered regolith and in the fractured bedrock. The aquifers developed in these areas are largely unconfined, locally developed and not spatially extensive. Generally, only modest groundwater supplies can be abstracted sustainably from these aquifers and large-scale groundwater well-field developments are not feasible. Because of semi-arid and arid conditions, especially in southern Angola, Namibia, Botswana, western South Africa, and western Zimbabwe, all have lower recharge rates and hence tend to place a higher value on their water resources than the humid countries. In these areas, groundwater recharge may be limited and probably largely localised to line and point sources such as streambeds and dam basins, respectively (Xu and Beekman, 2003). Surface water resources are largely ephemeral, and most perennial rivers in these areas receive their recharge from the humid areas. As a result, the groundwater resource has assumed great importance as the principal source of freshwater. In contrast the eastern and northern part of the SADC region may be characterised as humid tropical and humid equatorial climates. These areas generally have more abundant water resources, with perennial surface water. The groundwater resource, while potentially more abundant than in the arid countries, receives less attention and is generally not as carefully monitored and managed.

Drought is essentially endemic in the SADC Region and presents a major challenge to the achievement of sustainable development. Events like the 1991/92 drought had a regional impact, causing substantial socio-economic hardships, decline in public health on a large scale, land degradation and bio-diversity losses. Presently, about one third of the people in the region live in drought-prone areas. These extreme events are impacted by global climate changes, and their frequency and intensity are expected to increase in the future (UNESCO, 1999).

Groundwater is the largest water supply source for the domestic water supplies in the SADC Region, while it also plays a significant role in stock watering and other uses (see Table 1). Its contribution to total utilisation in the Region is estimated at 11.6% by volume, while in domestic supplies it contributes approximately 20% by volume (Molapo et al., 2000).

Groundwater contribution is very critical to the majority of the rural community and small towns. In areas where rural infrastructure is minimal, rural communities often rely only on informal, traditionally developed groundwater sources (i.e. hand-dug wells, springs, sand, and river abstraction). It should be noted that there is still a backlog of between 30 and 50% in terms of access to improved water sources in several countries of the region, the largest un-served portion of un-served being in the rural areas. Groundwater resources should thus be seen as strategic within the SADC (Molapo and Puyoo, 2002).

Groundwater's changing role can best be illustrated with the example of South Africa (Braune et al., 2008). Until the new National Water Act of 1998, groundwater was defined in law as 'private water' and was seen of local importance only. With the democratisation of the country in 1994 there was a strong policy shift towards providing basic services, including water and sanitation services, to the whole population as soon as possible. The indication at that time was that 15 m. people or about 40% of the population did not have the most basic form of water supply. By 2006 the backlog had been reduced to 4 m. and groundwater has played a major role in this regard. Already the rural domestic use from groundwater in South Africa has increased from 120x10 6 m 3 in 1986 to 310x10 6 m 3 /a in 2000. Overall, more than 60% of the country's population is supplied with water through groundwater and this number increases to 90% in some provinces.

Although the importance of groundwater as a viable and economically feasible source is now widely recognised in the Region, its importance for bigger settlements and larger-scale water supply is often underplayed. It is estimated that 36% of the urban population in the SADC Region relies on groundwater .

Groundwater is also a major source for small-scale irrigation and livestock farming in many of the SADC Member States. Groundwater for these purposes is largely developed at private level and, as such, reliable statistics are not available. It is estimated that groundwater now accounts for about 14% of the total irrigated area in Namibia, 18% in South Africa, and as much as 56% in Botswana (FAO AQUASTAT database). Small-scale irrigation using groundwater offers a big opportunity for enhancing the livelihoods of the poor in much of Africa and is set to increase in the near future (Wellfield Consulting Services & British Geological Survey, 2003;FAO, 2003).

Status of groundwater resource management in the SADC Region

An assessment of the status of groundwater resource management in Southern Africa was recently undertaken at a scoping (desk study) level. The purpose of the assessment was to position the Region for a possible piloting of the 2007 resolutions of AMCOW (African Ministers' Council on Water) regarding groundwater resource management in Africa (Braune et al., 2008).

The SADC Region was chosen because of its well-developed policies for regional development and IWRM, as well as its relatively strong focus on groundwater resources. The overarching goal of the SADC is 'Regional Integration and Poverty Eradication'. Cooperation in various sectors was initiated by way of protocols to the SADC Treaty, protocols being instruments in international law. In the case of water, there is the SADC Protocol on Shared Watercourses, which was enacted during 1998 and was revised in 2003. The Protocol fully caters for groundwater (SADC, 2000). At a planning level, work on a regional strategy for the newly formed water sector was initiated in 1996 and its first 5-year programme became the RSAP-IWRM (1999)(2000)(2001)(2002)(2003)(2004). One of the components of the integrated action plan is a Groundwater Programme. A comprehensive Regional Water Policy and a Regional Water Strategy have been developed since then. An important vehicle for implementing this policy is the existence of well-functioning river basin organisations (RBOs), mandated by the Protocol and operating under sound legislation and systems for planning and stakeholder involvement and embracing IWRM principles (SADC, 2005).

The approach adopted in the scoping study was to assess the groundwater resource management status in the SADC based on available groundwater documents and scientific literature from the area and to weigh it up against some form of generally accepted 'best practice', summarised from the international groundwater management literature, to obtain a measure of management status. The key premise for the assessment methodology was that groundwater resource management must take place within an IWRM framework and to achieve this, the IWRM Toolbox developed by the Global Water Partnership (Global Water Partnership, 2002) was used as the scope and content for the assessment under the main headings of 'Enabling Environment', Institutional Development' and 'Management Measures'. A management performance rating of 'good', 'limited' or 'below expectation' was assigned to different elements within this framework, by comparison with the benchmark provided in the best practice analysis.

The assessment took into account the socio-economic development situation and the status of water resource management in SADC to ensure that different aspects of groundwater management were relevant in the area.

SADC is made up of 14 Member States at different stages of development, but predominantly underdeveloped. Poverty is widespread in the sub-region, with an estimated 70% of the population living below the international poverty line of US$2/d (roughly ZAR20/d), and 40% living in extreme poverty (less than US$1/d) (Economic Commission for Africa, 2006). In spite of the economic imbalances amongst its Member States and the relatively small size of the market (only comparable to Belgium or Norway), in the African context the SADC's aggregate GDP of US$226 bn. is more than double that of ECOWAS, and equivalent to more than half the aggregate GDP of Sub-Saharan Africa (SSA). It also has the highest GNP per capita in the whole of SSA (Economic Commission for Africa, 2006).

The socio-economic conditions characterising the SADC sub-region include rapid population growth, high rates of urbanisation, high HIV/AIDS and malaria prevalence, high levels of poverty and income inequality, and a high incidence of food insecurity (Economic Commission for Africa, 2006). These socioeconomic drivers have placed an increasing demand for water resulting in increased stress on the limited water resources, and exacerbated competition and conflict between and among sectoral users (Economic Commission for Africa, 2006).

Many and diverse factors are affecting poverty in the region, of which water and its appropriate management is just one, albeit an important one. An integrated development approach is thus critical and this is what the Regional Indicative Strategic Development Plan tries to achieve in the SADC. In recognition of the magnitude of the poverty problem, the ultimate objective of the plan, designed to provide strategic direction to SADC programmes, projects and activities, is to deepen the integration agenda of SADC with a view to accelerating poverty eradication and the attainment of other economic and non-economic development objectives (SADC, 2003).

While the above analysis was only performed on readily available published material from the region and without individual country information, some general conclusions on the status of groundwater resource management in SADC can be drawn (Braune et al., 2008): • Access to reliable and safe water supplies is one of the highest regional development issues, particularly for the high percentage of poor living in largely un-served rural and also peri-urban areas. • SADC has made excellent progress to address groundwater in its comprehensive regional water resource policies and strategies and in initiating implementation through its Groundwater Management Programme. In this respect SADC is leading the other regional economic communities. • With regard to implementation in individual countries, the performance in groundwater resource management must still be generally rated as 'below expectation', compared to relevant international best practice. This is the case across the full spectrum of IWRM frameworks used in the analysis. • A few countries have legislation specifically focusing on groundwater, while others have modern integrated legislation. However, several countries have outdated legislation and, while harmonisation across the region is on the SADC agenda, this has not yet been implemented for groundwaterrelated legislation.

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• Despite the inability of bulk water supply solutions to address most of the widespread and diffuse water demand required to meet the remaining water services backlogs, there is still a general bias towards surface water resources in the region. Groundwater management links to groundwater-dependent sectors like agriculture, rural development, health and environment are not well established in policy or in practice. • Investment in groundwater, relative to its potential to address national objectives, is limited and is still offset by pollution and ineffective maintenance, making a large proportion of water points inoperative. • The relatively low priority accorded to groundwater is reflected in funding commitments, in particular for vital but completely inadequate groundwater monitoring, exploration and data gathering. • Major changes in institutional development for water service delivery and IWRM are taking place in SADC, but groundwater's unique role has not been adequately reflected in this new development, for example in river basin organisations and water user associations (WUAs). • While decentralisation is becoming a common feature in SADC, institutions have not yet been properly capacitated in terms of their new groundwater responsibility. • Lack of adequate monitoring and assessment of groundwater resources is resulting in poor attention to groundwater planning at all levels. This is particularly serious for droughtrisk management in which groundwater resources should play a critical role. • A lack of macro-planning for groundwater prevails, as most of the programmes are undertaken on an ad hoc or crisis response basis. This is one of the most problematic areas in relation to groundwater development (SADC-WSCU, 2001).

• The dependence of the majority of the SADC Member

States on external funding sources has an important bearing on groundwater development in these member states, particularly with respect to the establishment of a stable local development capacity. Donor-(and country-) funded groundwater projects are usually of short duration, with little if any hydrogeological monitoring input in their design.

Challenges and opportunities for groundwater within an IWRM framework

The above analysis indicates that, in relative terms, the SADC has made considerable progress in bringing important groundwater resources into an IWRM framework. However, this is not yet reflected in the groundwater resource management situation in individual countries, which is still rated 'below expectation'. This is obviously a much more general problem, than in this particular region of the world. Groundwater is often a cornerstone in the foundation of many economic and environmental systems. However, even in the contemporary accounts of 'integrated' water management, the unique nature of the groundwater system that underpins the entire resource base, is rarely discussed and addressed (Burke and Moench, 2000). Some of the particular challenges to groundwater resource management relate to its unique nature. It is a: • Hidden, unnoticed and less understood resource • Generally occurring, widely spread and locally accessible resource.

Because the links between users and the resource are often not apparent, and because many of the benefits associated with groundwater are public goods (such as environmental maintenance, health and poverty alleviation), the overall economic value of groundwater goes unrecognised (Burke and Moench, 2000). This situation has led to lack of attention in general to groundwater by decision-makers and a lack of progress in formally treating it as part of IWRM. At this moment, a potential opportunity for much increased recognition of groundwater's role in Africa may lie in the political pressures, touched on under 'IWRM challenges in Africa', for the water sector to address growth and development comprehensively. This can be illustrated with a few proposed groundwater-related responses of the South African water sector to the 'Water for Growth and Development Strategy' (DWAF, 2008):

• Focus on multiple uses of water for poverty alleviation and improved livelihoods • Need groundwater for multiple uses to achieve spatial equity • Need subsidisation of appropriate technology (for local resource development).

Besides the valuation there is the management issue. Because of its ubiquitous nature and relative ease of local access, there are widely distributed and generally dispersed abstraction points and many stakeholders, who are involved in its development, use, as well as misuse. This complicates the traditional national approaches to resource regulation and requires a very high degree of participative management. It also requires novel approaches to the systematic planning, financing and implementation of hundreds and even thousands of small, locally dispersed groundwater schemes (Braune et al., 2008 andBurke andMoench, 2000). In probably one of the most insightful groundwater resource management books entitled: 'Groundwater and Society -Resources, Tensions and Opportunities', Burke and Moench (2000) make a plea for the development of effective approaches, which in most cases will require a long-term process through which viable national, regional and local systems can evolve. Foster (2006) comes to a similar conclusion and sees this approach to resource governance and information provision to be functioning at both the micro-and macro-level and calls the desired approach a 'top-down facilitation of local actions'.

A number of major issues will have to be addressed from the beginning to encourage stakeholders to be more willing to contribute to the management efforts, in particular (Burke and Moench, 2000): • Valuation of groundwater: stakeholders respond to economic factors • Scientific understanding and data: without understanding, people are often unwilling to act • Education and social ethics: broad-based education is often central to building social support for management.

To become more systematic in developing flexible, integrated management systems, a strategic framework is seen as an essential precursor and progressive instrument for effective groundwater management (Burke and Moench, 2000;Global Water Partnership, 2002). In it, the intended relationships between diverse sets of interventions or management approaches and the development goals are specified. It should also specify the relationship between the diverse set of interventions themselves (individual, community and government roles and educational, economic, legal and regulatory mechanisms) -how together they are to form an approach to management that is internally consistent. A descriptive model change process for groundwater management is illustrated in Fig. 1 (Burke and Moench, 2000).

Available on website http://www.wrc.org.za ISSN 0378-4738 = Water SA Vol. 34 No. 6 (IWRM Special Edition) 2008ISSN 1816-7950 = Water SA (on-line)

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interpreted in relation to IWRM 'best practice'. A broad way
forward is discussed in relation to recent groundwater-related
resolutions adopted by the African Ministers Council on Water
(AMCOW).

TABlE 1
1Summary of groundwater dependency in the SADC RegionMember State
Rural
Urban
Agriculture
Industry
Overall dependency

* moderate, * minor Adjusted from Wellfield Consulting Services & British Geological Survey, 2003 Available on website http://www.wrc.org.za ISSN 0378-4738 = Water SA Vol.34 No. 6 (IWRM Special Edition) 2008
ISSN 1816-7950 = Water SA (on-line)

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source of drinking water
704One must take note, that such a strategic, multi-stakeholderdriven approach also still remains the major challenge in Africa for IWRM implementation as a whole. To make progress in this regard, the SADC Multi-Stakeholder Water Dialogue was introduced a few years ago(Global Water Partnership, 2008). It is therefore crucial that groundwater becomes an integral part of already active, major country and regional development / water resource management initiatives. Examples are:• The development of integrated water resource management and water efficiency plans in all countries • The widely supported and implemented Rural Water Supply and Sanitation Initiative (RWSSI) in Africa, which, inter alia, promotes the utilisation of a wide range of appropriate technologies, including improved shallow wells and boreholes fitted with hand pumps, spring development and rain-water harvesting as well as the maintenance of infrastructure by local communities (African Development Bank Group, 2005) • Devolution of water resource management to appropriate lower levels, which will allow widespread stakeholder participation, is being implemented in many parts of Africa. In SADC, water resource management, including the management of groundwater resources, is to take place in basin organisations and the provision of water services is to be the responsibility of local government(SADC, 2006).A major opportunity has arisen to take continent-wide action through a resolution by the African Ministers Council on Water (AMCOW) taken in 2007 at its 6 th Ordinary Session in Brazzaville, namely that AMCOW would become the custodian of a continent-wide strategic groundwater initiative. Its vision is expressed in a roadmap for an African Groundwater Commission which is to function under the umbrella of AMCOW to facilitate and direct regional, national, and international action on a number of fronts (AMCOW, 2008):VisionAn Africa where groundwater resources are valued and utilised sustainably by empowered stakeholders.Thrusts for actionAwarenessThis thrust must result in a widespread awareness of groundwater, its developmental role, its hydrological and ecosystem function, its vulnerability to human impact and approaches to its sustainable utilisation by key stakeholders at all levels.CapacityThis thrust must result in appropriate capacity, including policy and legislation, and institutional and human resources, to plan and implement sustainable groundwater utilisation at all levels.KnowledgeThis thrust must result in a knowledge base, including monitoring networks, resource assessment, best practice database, information systems and fundamental sciences, to enable the optimal utilisation of groundwater within an integrated water resource management (IWRM) framework.The first two practical groundwater resolutions taken by AMCOW (2008) must be seen as very strategic in their emphasis of the need to create synergies with major existing initiatives, namely:• Promote the institutionalisation of groundwater management by river basin organisations to ensure regional ownership of the initiative • Create synergy with the RWSSI to ensure groundwater's inclusion in resource assessment and the sustainable management of groundwater resources.Very significantly, the SADC has already taken the lead with a process, together with AMCOW, towards a stakeholder-responsive broad-based programme and approach to capacity-building for the integration of groundwater resource management into the region's IWRM initiative. Starting with a workshop in 2008, this could be followed in 2009 with the 3 rd SADC Water Dialogue, this time focusing on groundwater(SADC, 2008). This would be a major step forward for groundwater in the region, given the direction of Burke and Moench(2000)that, unless dialogue occurs, the perspectives of key stakeholders are unlikely to be reflected.What can be seen for this particular region of Africa is that processes are underway to try to address IWRM more comprehensively, with the intention of making groundwater an important part of the overall initiative.ConclusionsThe SADC region can be seen as representative of the wider African key development issue of poverty alleviation. Achieving water security is seen to be a crucial contribution to this regional goal. Given the highly spread-out nature of this target population, particularly in rural and informal urban areas, ubiquitous groundwater resources should be playing a strategic role in this region. However, despite the inability of bulk water supply solutions to address most of the widespread and diffuse water demand required to meet the remaining community water supply backlogs, there is still a general bias towards surface water resources in the region. While the SADC is leading the other regional economic communities in Africa in terms of addressing IWRM, and groundwater as part of it, in its comprehensive regional water resource policies and strategies, the performance in sustainable utilisation and management of groundwater resources in individual SADC countries must still be generally rated as 'below expectation', according to a recent scoping study and compared to relevant international best practice.A key finding has been that groundwater management links to groundwater-dependent sectors like agriculture, rural development, health and environment are not well established in policy or in practice. Internationally, there is a recognition that such a situation, although quite common, can only be addressed through a long-term process through which viable national, regional and local systems can evolve, within a strategic framework in which these intended relationships between diverse sets of interventions or management approaches and the development goals are brought out. Key issues are clarity on the roles and responsibilities of different institutions and the creation of effective co-ordination mechanisms between different agencies.The IWRM and the water efficiency plans that each country is committed to develop, offer the ideal opportunity to mainstream groundwater resource management in this way. Such groundwater components of national plans could also be the forerunner for addressing groundwater in basin plans. The AMCOW resolution on the institutionalisation of groundwater opens the door to such action.A number of major issues will have to be addressed from the beginning to make stakeholders more willing to contribute to the management efforts. Appropriate valuation of groundwater resources, with which very diverse stakeholders can identify, should be seen as an essential precursor to its sustainable management. Furthermore, without scientific understanding and data, people will remain unwilling to act. Last, but not least, broad-based education is often central to building social support for management.It is clear that a lack of appropriate valuation of the role of groundwater in SADC must be seen as the main cause for its inadequate mainstreaming as part of IWRM and national development strategies and programmes. The fresh thinking generated through the shift in political priorities from water for basic needs to water for growth and development should also take groundwater into a more sustainable utilisation environment, requiring integrated management and assessment. The new strategic initiatives for groundwater at both a continental and sub-regional level by AMCOW and SADC respectively provide a major opportunity to take this forward in a multi-partnership approach.
The Rural Water Supply and Sanitation Initiative. African Development Group, United Nations. AFRICAN DEVELOPMENT GROUP (2005) The Rural Water Supply and Sanitation Initiative. 22 April 2005, United Nations, New York.

Roadmap for the Africa Groundwater Commission. AMCOW. AMCOW (2008) Roadmap for the Africa Groundwater Commission. UNEP/UNESCO/UWC: Nairobi, Kenya.

Capacity Building for Groundwater Management in West and Southern Africa. Cap-Net Bgr, Waternet, Wa-Net, Geozentrum. HannoverBGR, CAP-NET, WATERNET, WA-NET (2007) Capacity Building for Groundwater Management in West and Southern Africa. Geozen- trum: Hannover.

Protocol for the Assessment of the Status of Sustainable Utilization and Management of Groundwater Resources -With Special Reference to Southern Africa. Braune E, Hollingworth B, Xu Y, Mahed Nel M, Solomon H, No. TT 318/08Water Research Commission. WRC ReportBRAUNE E, HOLLINGWORTH B, XU Y, NEL M, MAHED G and SOLOMON H (2008) Protocol for the Assessment of the Status of Sustainable Utilization and Management of Groundwater Resources -With Special Reference to Southern Africa. WRC Report No. TT 318/08. Water Research Commission, Pretoria, South Africa.

Burke Jj, Moench Mh, Groundwater and Society: Resources, Tensions and Opportunities. New York: United Nations. New YorkBURKE JJ and MOENCH MH (2000) Groundwater and Society: Resources, Tensions and Opportunities. New York: United Nations, New York.

Southern Africa Water Development Report. ECA/SA/TPUB/2005/4. ECONOMIC COMMISSION FOR AFRICA, ORGANISATION FOR AFRICAN UNITY AND AFRICAN DEVELOPMENT BANK (2000) Safeguarding Life and Development in Africa. A Vision for Water Resources Management in the 21 st Century. African Caucus Presentations -Second World Water Forum, The Hague, The Netherlands. Dwaf, 17.8.08FOOD AND AGRICULTURAL ORGANIZATION OF THE UNITED NATIONS. 25FAOWater ReportsDWAF (2008) Department of Water Affairs and Forestry Seminar on Water for Growth and Development, 17.8.08. Stockholm Water Week 2008, Sweden. ECONOMIC COMMISSION FOR AFRICA (2006) Southern Africa Water Development Report. ECA/SA/TPUB/2005/4. ECONOMIC COMMISSION FOR AFRICA, ORGANISATION FOR AFRICAN UNITY AND AFRICAN DEVELOPMENT BANK (2000) Safeguarding Life and Development in Africa. A Vision for Water Resources Management in the 21 st Century. African Caucus Presentations -Second World Water Forum, The Hague, The Neth- erlands, 18 March 2000. FOOD AND AGRICULTURAL ORGANIZATION OF THE UNITED NATIONS (2003) Groundwater Management -The Search for Prac- tical Approaches. Water Reports 25. Rome: FAO.

Groundwater for Life and Livelihoods -The Framework for Sustainable Use. Presentation at 4th World Water Forum. Foster S, MexicoFOSTER S (2006) Groundwater for Life and Livelihoods -The Frame- work for Sustainable Use. Presentation at 4th World Water Forum. 18 March 2006, Mexico. (www.iah.org).

Integrated Water Resources Management. Global Water Partnership, GWP Catalyzing Change Series. GLOBAL WATER PARTNERSHIP (2000) Integrated Water Resources Management. GWP Catalyzing Change Series.

Global Water Partnership, The Policy Guidance and Operational Tools on IWRM. GLOBAL WATER PARTNERSHIP (2002) The Policy Guidance and Operational Tools on IWRM.

Swaziland: Need for better management of water resources. GWP Information Note. INTEGRATED REGIONAL INFORMATION NETWORKS. The SADC Multi-Stakeholder Water DialogueGWP (2008) The SADC Multi-Stakeholder Water Dialogue. Maseru, Lesotho 14-15 May 2008. GWP Information Note. INTEGRATED REGIONAL INFORMATION NETWORKS (2002) Swaziland: Need for better management of water resources. www. reliefweb.int.

Groundwater Resource Management in the SADC Region: A Field of Regional Cooperation. Pandey Molapo P, Sk, Puyoo S, Cape TownIAH 2000 ConferenceMOLAPO P, PANDEY SK and PUYOO S (2000) Groundwater Resource Management in the SADC Region: A Field of Regional Cooperation; IAH 2000 Conference, Cape Town.

Transboundary Aquifer Management in the Context of Integrated Water Resources Management in the Southern African Development Community (SADC) region. Molapo P, Puyoo S, Proc. Int. Workshop. 2-4. Int. Workshop. 2-4Tripoli, Libya. SADCRevised Protocol on Shared Watercourses in the Southern African Development Community (SADCMOLAPO P and PUYOO S (2002) Transboundary Aquifer Manage- ment in the Context of Integrated Water Resources Management in the Southern African Development Community (SADC) region. Proc. Int. Workshop. 2-4 June 2002, Tripoli, Libya. SADC (2000) Revised Protocol on Shared Watercourses in the Southern African Development Community (SADC).

Wscu Sadc, No.1. SADCRegional Indicative Strategic Development Plan. Situation Analysis Report. ReportSADC, WSCU (2001) Situation Analysis Report. Report No.1. SADC (2003) Regional Indicative Strategic Development Plan.

Regional Strategic Action Plan for Integrated Water Resource Management. SADC. SADC (2005) Regional Strategic Action Plan for Integrated Water Resource Management.

SADC (2006) Regional Water Policy. SADC (2006) Regional Water Policy.

Announcement for SADC/AMCOW Workshop on Groundwater for Development in the SADC IWRM Initiative. Gaborone, BotswanaSADC (2008) Announcement for SADC/AMCOW Workshop on Groundwater for Development in the SADC IWRM Initiative. 18-19 November 2008, Gaborone, Botswana.

Groundwater Regulation and Guidelines: Crucial Components of Integrated Catchment Management in Zimbabwe. 'I' WARFSA/WaterNet Symposium: Sustainable Use of Water Resources. Beekman Sunguro S, He, Erbel K, Maputo, MozambiqueSUNGURO S, BEEKMAN HE and ERBEL K (2000) Groundwa- ter Regulation and Guidelines: Crucial Components of Integrated Catchment Management in Zimbabwe. 'I' WARFSA/WaterNet Symposium: Sustainable Use of Water Resources. 1-2 November 2000, Maputo, Mozambique.

Integrated Drought Management-Lessons for sub-Saharan Africa. Proceedings of the International Conference. the International ConferencePretoriaUNESCOUNESCO (1999) Integrated Drought Management-Lessons for sub- Saharan Africa. Proceedings of the International Conference. UNESCO-IHP, Pretoria, September 1999.

. UNITED NATIONS. 21AgendaUNITED NATIONS (1992) Agenda 21, Chapter 18. United Nations Conference on Environment and Development. 3-14 June 1992, Rio de Janeiro, Brazil..

Water Resources Development in Africa. U N Millennium, Task, On, Sanitation, 1861-571/02. WORLD WATER COUNCILWhat Will It Take? Millennium Project. Stockholm International Water Institute. Stockholm, Sweden; Mexico City, MexicoReport No. RFP # WBAfrica Regional Document. 4 th World Water ForumUN MILLENNIUM PROJECT TASK FORCE ON WATER AND SANITATION (2005) Health, Dignity and Development: What Will It Take? Millennium Project. Stockholm International Water Insti- tute, Stockholm, Sweden. WELLFIELD CONSULTING SERVICES & BRITISH GEOLOGICAL SURVEY (2003) SADC: Regional Situation Analysis. Report No. RFP # WB 1861-571/02. WORLD WATER COUNCIL (2006) Water Resources Development in Africa. Africa Regional Document. 4 th World Water Forum, 16-22 March 2006, Mexico City, Mexico.

World Summit on Sustainable Development. Wssd Plan, Implementation, JohannesburgWSSD PLAN OF IMPLEMENTATION (2002) World Summit on Sus- tainable Development, Johannesburg 2002 (www.johannesburg- summit.org).

Groundwater Recharge Estimation in Southern Africa. 92-9220-000-3UNESCO IHP Series. XU and BEEKMAN64XU and BEEKMAN (eds.) (2003) Groundwater Recharge Estima- tion in Southern Africa, UNESCO IHP Series No. 64, published by UNESCO Paris. ISNB 92-9220-000-3.

Integrated Water Resources Management (IWRM) Plan for Zambia. ISBN 10: 0-415-41167-X. UK. ZAMBIAN WATER PARTNERSHIPTaylor & Francis / BalkemaGroundwater Pollution in AfricaXU Y and USHER B (eds.) (2006) Groundwater Pollution in Africa. Published by Taylor & Francis / Balkema, ISBN 10: 0-415-41167-X. UK. ZAMBIAN WATER PARTNERSHIP (2008) Integrated Water Resources Management (IWRM) Plan for Zambia.


Submucosal Epinephrine Injection Before Endoscopic Papillectomy: Less is More?

Roy L J Van Wanrooij
Department of Gastroenterology and Hepatology
Amsterdam UMC
Vrije Universiteit Amsterdam
AGEM institute
Amsterdam

Jeanin E Van Hooft firstname.lastname@example.com
Department of Gastroenterology and Hepatology
Department of Gastroenterology and Hepatology
Leiden University Medical Center
LeidenThe Netherlands

Leiden University Medical Center
Albinusdreef 22333 ZALeidenThe Netherlands

Jeanin E Van Hooft
Submucosal Epinephrine Injection Before Endoscopic Papillectomy: Less is More?
Received: June 1, 2021 Revised: June 17, 2021 Accepted: June 17, 2021COMMENTARY Open Access See "Efficacy of Hypertonic Saline-Epinephrine Local Injection Around the Anal Side before Endoscopic Papillectomy for Ampullary Tumors" by Naoki Okano, Yoshinori Igarashi, Ken Ito, et al., on page 706-712. Correspondence:
Since the first endoscopic papillectomy in 1983, the technique has developed further and has become the first-line treatment for papillary lesions considered endoscopically resectable. 1,2 A recent meta-analysis of endoscopic papillectomy reported a technical success rate of 94.2% and an oncologically curative resection rate of 87.1%. 3 Adverse events are common and reported in almost one in four patients, with intra-procedural bleeding and post-procedural pancreatitis occurring in 11% of the cases.3Submucosal epinephrine injection is commonly used for endoscopic resections in the gastrointestinal tract and is known to prevent intraprocedural bleeding during endoscopic papillectomy. However, one randomized controlled trial (RCT) compared submucosal epinephrine injection followed by endoscopic papillectomy to direct snare papillectomy and found similar rates of intra-procedural bleeding (42% vs. 46%) in both groups. 4 Complete resection rates were clearly lower (50% vs. 81%) in the group that received epinephrine injection, which is in line with the results of another retrospective study.4,5The explanation for the lower complete resection rates is that the papillary complex itself is fixed to the rigid sphincter of Oddi complex, while the surrounding tissue becomes adherent after submucosal injection and buries the papilla, which complicates endoscopic resection. The recent guideline of the European Society of Gastrointestinal Endoscopy (ESGE) recommends against submucosal injection based on these studies, unless it involves a laterally spreading papillary adenoma.2In this issue of Clinical Endoscopy, Okano et al. modified the submucosal injection technique so that it does not hinder endoscopic resection. 6 Instead of injecting into the entire papillary area, the authors only injected epinephrine around the distal part of the papilla where most of the blood vessels are located and bleeding is common. Outcomes of patients treated with this technique since 2010 were compared to those treated before 2010 using the direct snare technique. Intraprocedural bleeding was significantly less in the epinephrine injection group (4.8% vs. 20.5%). In addition, the rate of post-procedural pancreatitis was significantly lower in the epinephrine injection group (11.1% vs. 31.8%). The authors hypothesized that a longer duration of the procedure and additional manipulation associated with the treatment of the bleeding might have increased the risk of pancreatitis in the direct snare group. The rates of complete resection were not negatively affected by the submucosal injection, possibly because of the modified technique. Thus, the authors concluded that local treatment with epinephrine injection prevented both intra-procedural bleeding and post-procedural pancreatitis.Delayed ( >24 h) bleeding is also not uncommon after endoscopic papillectomy due to the thermal effect that lags behind and exposes the blood vessels to the risk of delayed bleeding. Although the vasoconstrictive effect of epinephrine injection wears off within 10-30 minutes and could therefore potentially underestimate the bleeding risk, no significant in-

Since the first endoscopic papillectomy in 1983, the technique has developed further and has become the first-line treatment for papillary lesions considered endoscopically resectable. 1,2 A recent meta-analysis of endoscopic papillectomy reported a technical success rate of 94.2% and an oncologically curative resection rate of 87.1%. 3 Adverse events are common and reported in almost one in four patients, with intra-procedural bleeding and post-procedural pancreatitis occurring in 11% of the cases. 3 Submucosal epinephrine injection is commonly used for endoscopic resections in the gastrointestinal tract and is known to prevent intraprocedural bleeding during endoscopic papillectomy. However, one randomized controlled trial (RCT) compared submucosal epinephrine injection followed by endoscopic papillectomy to direct snare papillectomy and found similar rates of intra-procedural bleeding (42% vs. 46%) in both groups. 4 Complete resection rates were clearly lower (50% vs. 81%) in the group that received epinephrine injection, which is in line with the results of another retrospective study. 4,5 The explanation for the lower complete resection rates is that the papillary complex itself is fixed to the rigid sphincter of Oddi complex, while the surrounding tissue becomes adherent after submucosal injection and buries the papilla, which complicates endoscopic resection. The recent guideline of the European Society of Gastrointestinal Endoscopy (ESGE) recommends against submucosal injection based on these studies, unless it involves a laterally spreading papillary adenoma. 2 In this issue of Clinical Endoscopy, Okano et al. modified the submucosal injection technique so that it does not hinder endoscopic resection. 6 Instead of injecting into the entire papillary area, the authors only injected epinephrine around the distal part of the papilla where most of the blood vessels are located and bleeding is common. Outcomes of patients treated with this technique since 2010 were compared to those treated before 2010 using the direct snare technique. Intraprocedural bleeding was significantly less in the epinephrine injection group (4.8% vs. 20.5%). In addition, the rate of post-procedural pancreatitis was significantly lower in the epinephrine injection group (11.1% vs. 31.8%). The authors hypothesized that a longer duration of the procedure and additional manipulation associated with the treatment of the bleeding might have increased the risk of pancreatitis in the direct snare group. The rates of complete resection were not negatively affected by the submucosal injection, possibly because of the modified technique. Thus, the authors concluded that local treatment with epinephrine injection prevented both intra-procedural bleeding and post-procedural pancreatitis.

Delayed ( >24 h) bleeding is also not uncommon after endoscopic papillectomy due to the thermal effect that lags behind and exposes the blood vessels to the risk of delayed bleeding. Although the vasoconstrictive effect of epinephrine injection wears off within 10-30 minutes and could therefore potentially underestimate the bleeding risk, no significant in-crease in delayed bleeding was observed in the study by Okano et al. 6 Several technical interventions to prevent late bleeding have been studied. Prophylactic clip placement on the frenulum, similar to that in the injection site in the study by Okano et al, 6 compresses the local blood vessels and thus prevents bleeding without the risk of accidentally blocking the bile or pancreatic duct. A retrospective, monocentric study showed a lower incidence (5%) of delayed bleeding in 40 patients with a prophylactic clip compared to 23% in a historical cohort of 40 patients without clip placement. 7 Another strategy is to use argon plasma coagulation (APC); however, treating only the edges of the resection margin with APC did not reduce the incidence of delayed bleeding in an RCT involving 54 patients. 8 Perhaps the key to success in preventing delayed bleeding is to treat the well-vascularized distal part of the papilla. Nevertheless, the risk of delayed bleeding is associated with the size of the resection, which implicates that bleeding in larger lesions will increasingly occur from somewhere other than the frenulum area and cannot be prevented. 9 Treating delayed bleeding includes the discontinuation of anticoagulants and blood transfusion, if applicable, and applying local endoscopic therapy using a coagrasper. In hemodynamically unstable patients in whom the endoscopic therapy failed, an emergency arterial embolization was performed.

The hypothesis put forth by the authors that the treatment of intra-procedural bleeding might increase the risk of pancreatitis seems prudent; however, there is a lack of compelling evidence since the duration of the procedure was not presented in their paper, and evidence from the current literature is lacking. To prevent post-procedural pancreatitis, ESGE recommends the administration of a rectal nonsteroidal anti-inflammatory drug (NSAID) in all patients without an NSAID allergy and placement of a prophylactic pancreatic stent in patients without a pancreas divisum. 2 Should we change our clinical practice? The retrospective nature of this monocentric study, which compares the outcomes at two different time periods, does not justify such a modification of the current treatment strategy; however, it does validate a new prospective, comparative study on this subject. Papillary neoplasia is rare; therefore, data on this subject are scarce, and conducting large RCTs is challenging. However, the rates of adverse events associated with endoscopic papillectomy are high, and other issues such as the significantly high recurrence rates need to be addressed in future studies that require a multicentric, and preferably, an international approach. 10 Retrospective studies encompassing relatively large groups of patients, which are analyzed using propensity score matching, could also aid in creating a more robust, evidence-based foundation.

In conclusion, submucosal injection of epinephrine only on the distal side of the papilla might prevent intra-procedural bleeding without affecting the rates of complete resection, and therefore "less is more" seems to apply here. The question now is how more evidence can be gathered so that this modified injection method could imply a change in the future update of the recently published ESGE guidelines.

Conflicts of Interest

J.E. van Hooft received a research grant from Cook Medical and received consultancy fees from Medtronic, Boston Scientific, Cook Medical, Olympus. The other author has no potential conflicts of interest.

Funding

 Author Contributions
Two cases with ampullary cancer who underwent endscopic excision. K Suzuki, U Kantou, Y Murakami, Prog Dig Endosc. 23Suzuki K, Kantou U, Murakami Y. Two cases with ampullary cancer who underwent endscopic excision. Prog Dig Endosc. 1983;23:236-239.

Endoscopic management of superficial nonampullary duodenal tumors: european society of gastrointestinal endoscopy (ESGE) guideline. G Vanbiervliet, A Moss, M Arvanitakis, Endoscopy. 53Vanbiervliet G, Moss A, Arvanitakis M, et al. Endoscopic management of superficial nonampullary duodenal tumors: european society of gas- trointestinal endoscopy (ESGE) guideline. Endoscopy 2021;53:522-534.

Endoscopic papillectomy for neoplastic ampullary lesions: a systematic review with pooled analysis. M Spadaccini, A Fugazza, L Frazzoni, United European Gastroenterol J. 8Spadaccini M, Fugazza A, Frazzoni L, et al. Endoscopic papillectomy for neoplastic ampullary lesions: a systematic review with pooled analysis. United European Gastroenterol J 2020;8:44-51.

A prospective multicenter study of submucosal injection to improve endoscopic snare papillectomy for ampullary adenoma. J J Hyun, T H Lee, J-S Park, J-H Han, S Jeong, S M Park, Gastrointest Endosc. 85Hyun JJ, Lee TH, Park J-S, Han J-H, Jeong S, Park SM, et al. A prospec- tive multicenter study of submucosal injection to improve endoscopic snare papillectomy for ampullary adenoma. Gastrointest Endosc 2017;85:746-55.

Effect of submucosal injection in endoscopic papillectomy of ampullary tumor: propensity-score matching analysis. United. K H Chung, S H Lee, J H Choi, European Gastroenterol J. 6Chung KH, Lee SH, Choi JH, al. Effect of submucosal injection in en- doscopic papillectomy of ampullary tumor: propensity-score matching analysis. United European Gastroenterol J 2018;6:576-585.

Efficacy of hypertonic saline-epinephrine local injection around the anal side before endoscopic papillectomy for ampullary tumors. N Okano, Y Igarashi, K Ito, Clin Endosc. 54Okano N, Igarashi Y, Ito K, et al. Efficacy of hypertonic saline-epineph- rine local injection around the anal side before endoscopic papillectomy for ampullary tumors. Clin Endosc 2021;54:706-712.

Effect of preventive closure of the frenulum after endoscopic papillectomy: a prospective pilot study. K Kagawa, K Kubota, Y Kurita, J Gastroenterol Hepatol. 35Kagawa K, Kubota K, Kurita Y, et al. Effect of preventive closure of the frenulum after endoscopic papillectomy: a prospective pilot study. J Gas- troenterol Hepatol 2020;35:374-379.

Can prophylactic argon plasma coagulation reduce delayed post-papillectomy bleeding? A prospective multicenter trial. J K Yang, J J Hyun, T H Lee, J Gastroenterol Hepatol. 36Yang JK, Hyun JJ, Lee TH, et al. Can prophylactic argon plasma coagu- lation reduce delayed post-papillectomy bleeding? A prospective multi- center trial. J Gastroenterol Hepatol 2021;36:467-473.

Methods and outcome of the endoscopic treatment of ampullary tumors. J-W Poley, S Campos, Ther Adv Gastrointest Endosc. 132631774519899786Poley J-W, Campos S. Methods and outcome of the endoscop- ic treatment of ampullary tumors. Ther Adv Gastrointest Endosc 2020;13:2631774519899786.

Endoscopic papillectomy; a retrospective international multicenter cohort study with long-term follow-up. J A Fritzsche, A Klein, M J Beekman, Surg Endosc. Fritzsche JA, Klein A, Beekman MJ, et al. Endoscopic papillectomy; a retrospective international multicenter cohort study with long-term follow-up. Surg Endosc 2020 Nov 6 [Epub].

. 10.1007/s00464-020-08126-xhttps://10.1007/s00464-020- 08126-x.


Saline volume expansion and cardiovascular physiology: novel observations, old explanations, and new questions
2004

Professor and Chairman,James L Robotham email@example.com
Department of Anesthesiology
University of Rochester
RochesterNew YorkUSA

Saline volume expansion and cardiovascular physiology: novel observations, old explanations, and new questions

Critical Care
8200410.1186/cc2944)Available online Related to Research by Kumar et al., see issue 8.3, page 201afterloadcardiovascular physiologycontactilityhemodynamicspreloadventricular function
315 CO = cardiac output; Ea = maximal arterial systolic elastance; EDV = end-diastolic volume; EF = ejection fraction; Emax = maximal ventricular systolic elastance; ESV = end-systolic volume; LV = left ventricular; Pes = end-systolic pressure; RV = right ventricular; SV = stroke volume; Vo = zero Pes intercept of Emax from a pressure-volume diagram.The article by Kumar and coworkers [1] is one of a series of three papers [2,3] by the authors addressing the acute hemodynamic events that accompany plasma volume expansion over 3-5 hours in healthy young adult volunteers. Taking into account all three reports, the most interesting finding is that increases in stroke volume (SV) following saline infusion over 3 hours may be variably related to increases in left ventricular (LV) end-diastolic volume (EDV) and/or decreases in LV end-systolic volume (ESV). The second interesting finding, from one of the reports [3],CommentaryAbstractIn a clinical investigation, Kumar and coworkers reported the hemodynamic events that accompany plasma volume expansion over 3 hours in healthy adult volunteers, and found that increases in stroke volume (SV) may be related to increases in left ventricular (LV)/right ventricular (RV) end-diastolic volume, as they expected, but also to decreases in LV/RV end-systolic volume. The latter finding suggests increased contractility and/or decreased afterload, which do not fit with their perception that clinicians ascribe increases in SV to increases in end-diastolic volume based on Starling's work. Increased ejection fraction and decreased vascular resistances were also observed. The same authors recently reported novel data suggesting that reduced blood viscosity may account for the observed reduction in vascular resistances with saline volume expansion. However, the variances in preload and afterload, along with uncertainty in estimates of contractility, substantially limit their ability to define a primary mechanism to explain decreases in LV end-systolic volume. A focus on using ejection fraction to evaluate the integrated performance of the cardiovascular system is provided to broaden this analytic perspective. Sagawa and colleagues described an approach to estimate the relationship, under clinical conditions, between ventricular and arterial bed elastances (i.e. maximal ventricular systolic elastance [Emax] and maximal arterial systolic elastance [Ea]), reflecting ventricular-arterial coupling. I used the mean data provided in one of the reports from Kumar and coworkers to calculate that LV Emax decreased from 1.09 to 0.96 mmHg/ml with saline volume expansion, while Ea decreased from 1.1 to 0.97 mmHg/ml and the SV increased (i.e. the increase in mean SV was associated with a decrease in mean afterload while the mean contractility decreased). The results reported by Kumar and coworkers invite further studies in normal and critically ill patients during acute saline-induced plasma volume expansion and hemodilution. If reduced viscosity decreases afterload, then this raises the questions by what mechanism, and what is the balance of benefit and harm associated with reduced blood viscosity affecting oxygen delivery? Why the mean Emax might decrease must be evaluated with respect to benefit in reducing ventricular work or a negative inotropic effect of saline.

involves novel data suggesting that the acute dilution by reducing blood viscosity may account for a substantial proportion of the reduction in vascular resistance in the systemic and pulmonary arterial beds, which was consistently observed at 3 hours, but diminished after the infusion was stopped and normal viscosity re-established. The authors did not investigate possible endothelial mechano-transduction mechanisms, or determine whether the reduction in systemic venous resistance that accompanied this decrease in viscosity might alter the time constant for venous return, thus enhancing cardiac output (CO).

The fundamental findings (albeit with substantial variability among the individuals studied) were that 3 l of saline infused over 3 hours increases the LVEDV, RVEDV, CO, SV and ejection fraction (EF), whereas the LVESV, and systemic and pulmonary vascular resistances decreased. Consistent with many previous reports, changes in RVEDV and LVEDV did not consistently correlate with changes in ventricular enddiastolic pressures [2], but the unexpectedly high central venous and pulmonary capillary wedge pressures reported [1][2][3] are consistent with and account for this finding [4]. Multiple measures of LV contractility, which are to varying degrees load dependent, suggest no change or an increase in ventricular contractile function. However, the variances in preload and afterload, along with the uncertainty in estimates of contractility, substantially limit the ability of the authors to draw any conclusions with respect to a primary mechanism underlying the decreases in LVESV.

My comments focus on the Frank-Starling mechanism, which the authors use as the basis for their argument that clinicians have incorrectly assumed that increases in SV and CO with plasma volume expansion were determined by an increase in the LVEDV. An a priori physiologic analysis of an increase in plasma volume may place the argument in a broader perspective. Otto Frank, in 1899, reported the first experimentally derived ventricular pressure-volume diagrams, emphasizing that the end-systolic pressure and volume are determined by events that occur in the immediately preceding cardiac cycle. Starling never plotted a pressure-volume relationship based on raw experimental data, although one of his students did [5]. Starling did plot: an end-systolic and end-diastolic isovolumic pressure-volume relationship from Frank's work; CO against mean right atrial pressure; and external work against EDV [5]. Starling's 'Law of the Heart' is frequently misunderstood in interpreting Starling's use of mean right atrial pressure as preload. Preload is now more accurately defined as the ventricular EDV. Thus, using relatively healthy isolated hearts with ability to control the mean arterial pressure, Starling found a strong correlation between the mean right atrial pressure and the SV, with small changes in afterload and heart rate being relatively unimportant. He did postulate that a larger ventricular volume permitted a larger chemically active surface to be exposed, hence increasing the force and thus the SV, when the afterload was maintained relatively constant by experimental means.

Indeed, years later Sagawa and coworkers [5], using computer controlled isolated ventricles, demonstrated that the end-systolic pressure-volume relationship (Pes-ESV) was a straight line, reflecting the maximum ventricular systolic elastance (Emax) of the ventricle. Emax served as a load independent measure of contractility; as the EDV increased, both ESV and the SV would increase (Fig. 1). The degree to which the ESV and SV changed with increasing EDV could be altered by changing the afterload (or more precisely the impedance, incorporating arterial vascular resistance, compliance, and inertance) or contractility. Experimentally, with contractility constant while acutely increasing EDV, one could first reduce afterload to an extremely low value and then progressively increase the afterload to limit ejection. This would yield serial results showing the following: first a decreased ESV and increased SV; then an increased ∆SV = increased ∆EDV; and finally an increased ESV = EDV with SV = 0 when the afterload is sufficient to prevent ejection.

If one uses atrial pressure as a measure of preload (as did Starling), then the diastolic compliance of the ventricle would define the volume change, with pericardial constraint (when present) becoming the dominant factor defining the shape of the diastolic pressure-volume relationship [4,6,7]. Only by instantaneously controlling very precisely the vascular input impedance (afterload) and contractility during a single cardiac cycle will the increase in EDV equal the increase in SV [5]. To be noted in passing, radionuclide cineangiography findings in one of the reports from Kumar and coworkers [2] showed a statistically significant increase of 10% (8 ml) in LVEDV and RVEDV with acute volume loading, and a reasonable correlation of ∆SV respectively with ∆RVEDV and ∆LVEDV. The decrease in ESV in both ventricles was only 2 ml, and four out of 12 individuals exhibited decreases in RVEDV with volume loading. These findings suggest that ventricular interdependence is not a dominant factor among the physiologic mechanisms. However, the unexpected finding in most of these studies was that the average central venous pressure was approximately 9.5 mmHg at baseline in supine individuals who had been NPO overnight, and increased to an average of 12.5 mmHg, while pulmonary capillary wedge pressure was 10 mmHg at baseline and increased on average to 15 mmHg. This strongly suggests either that the zero calibration position was problematic or that the individuals' control states were moderately hypervolemic, further limiting extrapolation of the results to hypovolemic patients.

Perhaps the easiest way to evaluate the clinical implications of acute plasma volume loading in these studies is to consider the EF. This parameter is widely used, incorrectly by most, as a measure of ventricular function [8]. It is rather a fascinating parameter that integrates contractility, preload, afterload, and Vo (the zero pressure intercept of the endsystolic pressure-volume relationship). If preload, afterload, and Vo are all maintained constant, then a change in EF is a measure of ventricular contractility. However, mathematically, EF will increase if either EDV or Vo increase because of the following relationship:

EF = ([EDV -ESV]/EDV) -Vo/EDV

This equation can be rewritten as follows:

EF = 1 -(Pes/EDV)(1/Emax) -(Vo/EDV)

Note that EF reflects the influences of preload (EDV), afterload (Pes), Vo (increases associated clinically with heart failure), and contractility (Emax). Thus, changes in any or all of the physiologic parameters that define EF can result in a myriad of combinations that preclude use of EF as a definitive measure of change in any one of them under clinical conditions. Indeed, the widespread application of EF as a clinical tool is precisely because it integrates all of these parameters into a single number that reflects the overall clinical state of the coupled ventricular-arterial systems [8]. However, it is clear that a decreased afterload and/or increased contractility must be present in the reports from Kumar and coworkers [1][2][3] for the LVESV to decrease and for SV and CO to increase.

Perhaps the most useful insight into use of EF from the reports from Kumar and coworkers is as follows; if EF remains relatively constant, even accepting a slight increase due to the mathematical consequence of increasing EDV, then the distribution of this increase will be proportional to EF (i.e. if EF = 0.6, then 60% of the increase in EDV will equal the increase in SV). Thus, one would predict increases in EDV, ESV, and SV. At the two extremes, if EF = 0.9 and the EDV increases 10 ml, then 9 ml will added to the SV and 1 ml to the ESV. Conversely, if EF = 0.1 and the EDV increases 10 ml, then 1 ml will be added to the SV and 9 ml to the ESV, assuming constant afterload and contractility. This raises the serious question as to whether one can generalize the findings of volume expansion in healthy volunteers to seriously ill patients who are variably hypovolumic and vasoconstricted, or septic and vasodilated with impaired contractility, given the variance in baseline conditions existing in myocardial and endothelial function as regulated by neural and humoral factors in addition to administered pharmaceutical agents in such patients. To my knowledge, the degree to which a change in viscosity would further affect afterload or venous return, when the mechanoreceptor function of the endothelium is markedly altered during an inflammatory state, has not been studied in the clinical setting.

Returning to the results of the three reports from Kumar and coworkers [1][2][3], including the one published in this journal, the critical question that remains unanswered is the primary mechanism that would explain a decrease in ESV that appears transiently during the time of maximum volume expansion and hemodilution with saline. The authors focus on increased EF, and in one report [3] measures of Pes/LVESV suggest that contractility has increased, although multiple other estimates of contractility exhibit no change. Overall, however, the largest consistent changes that they observe are increases in SV and CO with decreases in pulmonary and systemic vascular resistances. Although in many individuals preload increases would appear to account for much of the increase in SV, given little change in contractility and a decreased afterload, the series of reports lacks a rigorous evaluation to address the key questions directly.

It would seem possible that the authors and others who might replicate this study in normal or critically ill patients should turn to the classic book by Sagawa and coworkers published in 1988 [5]. Chapter 5 in that book describes a relatively straightforward approach to estimating the relationship under clinical conditions between ventricular and arterial bed elastances (i.e. Emax and Ea, reflecting ventricular-arterial coupling). Briefly, by plotting Emax and Ea with Pes versus SV on pressure-volume axes, the two straight lines -one with a negative slope and the other with a positive slope -must intersect at the point where a common Pes and SV occur (Fig. 2). I used mean data provided in a prior report from Kumar and coworkers [3] that allow this to be done. The results were that LV Emax decreased from 1.09 to 0.96 mmHg/ml with saline volume expansion, while Ea decreased from 1.1 to 0.97 mmHg/ml and the SV increased. Thus, in that cohort of 32 male volunteers in whom there was a statistically significant decrease in systemic vascular arterial resistance, the mean results are consistent with a decrease in systemic afterload rather than an increase in contractility accounting for the increase in SV and decrease in ESV. Any statistical significance of this analysis is of course lacking until the authors derive Emax and Ea for each individual before and after volume expansion, and then perform a complete statistical analysis on all of the data.

Bringing this all back to the clinical application of EF [8], the relationship between Emax and Ea can be derived as follows:
EF = (Emax/[Emax + Ea])(1 -Vo/EDV)
This restates the conclusion that EF is an effective clinical measure because it provides a single number that is sensitive to changes in ventricular function, arterial impedance, and the poorly understood Vo relative to EDV.

In conclusion, the findings presented by Kumar and coworkers invite further studies in normal and critically ill patients during acute saline induced plasma volume expansion or hemodilution. Starling's Law was derived under highly controlled experimental circumstances, such that assumptions that volume expansion should increase SV by increases in preload alone in a clinical setting requires consideration of a far more complex (patho)physiological analysis. If Kumar and coworkers suggested mechanism of transient lowering of viscosity is correct, then this would explain a dominant role of reducing afterload on both right and left ventricles. It would also raise questions regarding the mechanism that is responsible and regarding the balance of benefit and harm associated with reduced blood viscosity affecting oxygen delivery. Why the mean Emax might decrease must be evaluated with respect to likely benefit in reducing ventricular work and oxygen consumption, or reflecting a negative inotropic effect of saline that is masked by the reduced afterload effect. Furthermore, the possible role played by reduced viscosity in the resistance to venous return could be a logical additional consequence if the same occurs on the arterial side. The door is open for clinicians to explore these temporal physiologic observations and many other related questions safely in a wide variety of normal and pathologic conditions.
 Competing interestsThe author declares that he has no competing interests.
Preload-independent mechanisms contribute to increased stroke volume following large volume saline infusion in normal volunteers: a prospective interventional study. A Kumar, R Anel, E Bunnell, S Zanotti, K Habet, C Haery, S Marshall, M Cheang, A Neumann, A Ali, Crit Care. 8Kumar A, Anel R, Bunnell E, Zanotti S, Habet K, Haery C, Marshall S, Cheang M, Neumann A, Ali A, et al.: Preload-independent mechanisms contribute to increased stroke volume following large volume saline infusion in normal volunteers: a prospec- tive interventional study. Crit Care 2004, 8:R128-R136.

Pulmonary artery occlusion pressure and central venous pressure fail to predict ventricular filling volume, cardiac performance, or the response to volume infusion in normal subjects. A Kumar, R Anel, E Bunnell, K Habet, S Zanotti, S Marshall, A Neumann, A Ali, M Cheang, C Kavinsky, Crit Care Med. 32Kumar A, Anel R, Bunnell E, Habet K, Zanotti S, Marshall S, Neumann A, Ali A, Cheang M, Kavinsky C, et al.: Pulmonary artery occlusion pressure and central venous pressure fail to predict ventricular filling volume, cardiac performance, or the response to volume infusion in normal subjects. Crit Care Med 2004, 32:691-699.

Effect of large volume infusion on left ventricular volumes, performance and contractility parameters in normal volunteers. A Kumar, R Anel, E Bunnell, K Habet, A Neumann, D Wolff, R Rosenson, M Cheang, J E Parrillo, Intensive Care Med. 30Kumar A, Anel R, Bunnell E, Habet K, Neumann A, Wolff D, Rosenson R, Cheang M, Parrillo JE: Effect of large volume infu- sion on left ventricular volumes, performance and contractility parameters in normal volunteers. Intensive Care Med 2004, 30:1361-1369.

Effects of aortic constriction during experimental acute right ventricular pressure loading. Further insights into diastolic and systolic ventricular interaction. D R Hamilton, R S Dani, R A Semlacher, E R Smith, T M Kieser, J V Tyberg, Circulation. 92Hamilton DR, Dani RS, Semlacher RA, Smith ER, Kieser TM, Tyberg JV: Effects of aortic constriction during experimental acute right ventricular pressure loading. Further insights into diastolic and systolic ventricular interaction. Circulation 1995, 92:546-554.

K Sagawa, L Maughan, H Suga, K Sunagawa, Cardiac Contraction and the Pressure-Volume Relationship. OxfordOxford Press1988Sagawa K, Maughan L, Suga H, Sunagawa K: Cardiac Contrac- tion and the Pressure-Volume Relationship. Oxford: Oxford Press; 1988:3-41.

Influence of the pericardium on ventricular loading during respiration. M Takata, W Mitzner, J L Robotham, J Appl Physiol. 68Takata M, Mitzner W, Robotham JL: Influence of the peri- cardium on ventricular loading during respiration. J Appl Physiol 1990, 68:1640-1650.

Ventricular external constraint by the lung and pericardium during positive end-expiratory pressure. M Takata, J L Robotham, Am Rev Respir Dis. 143Takata M, Robotham JL: Ventricular external constraint by the lung and pericardium during positive end-expiratory pressure. Am Rev Respir Dis 1991, 143:872-875.

Ejection fraction revisited. J L Robotham, M Takata, M Berman, Y Harasawa, Anesthesiology. 74Robotham JL, Takata M, Berman M, Harasawa Y: Ejection frac- tion revisited. Anesthesiology 1991, 74:172-183.