Conventional pneumoperitoneum compared with abdominal wall lift for laparoscopic cholecystectomy. Randomized trial of low-pressure carbon dioxide-elicited pneumoperitoneum versus abdominal wall lifting for laparoscopic cholecystectomy. Randomized comparison of conventional carbon dioxide insufflation and abdominal wall lifting for laparoscopic cholecystectomy. Abdominal wall lift versus positive-pressure capnoperitoneum for laparoscopic cholecystectomy: randomized controlled trial. Laparoscopic cholecystectomy using abdominal wall retraction. Hemodynamics and gas exchange, a comparison with conventional pneumoperitoneum. Laparoscopic cholecystectomy with carbon dioxide pneumoperitoneum is safe even for high-risk patients. Pneumoperitoneum versus abdominal wall lift: effects on central haemodynamics and intrathoracic pressure during laparoscopic cholecystectomy. Randomized comparison between low-pressure laparoscopic cholecystectomy and gasless laparoscopic cholecystectomy. Randomized comparison of the neuroendocrine response to laparoscopic cholecystectomy using either conventional or abdominal wall lift techniques. A prospective randomized trial comparing pneumoperitoneum and U-shaped retractor elevation for laparoscopic cholecystectomy. Comparison of pneumoperitoneum and abdominal wall lifting as to hemodynamics and surgical stress response during laparoscopic cholecystectomy. Gasless laparoscopic cholecystectomy is not more time-consuming. Splanchnic and renal deterioration during and after laparoscopic cholecystectomy: a comparison of the carbon dioxide pneumoperitoneum and the abdominal wall lift method. Laparoscopic and laparotomic cholecystectomy: a randomized trial comparing postoperative respiratory function. Hormone-cytokine response. Pneumoperitoneum vs abdominal wall-lifting in laparoscopic cholecystectomy. Hemodynamic and pulmonary changes during open, carbon dioxide pneumoperitoneum and abdominal wall-lifting cholecystectomy. A prospective, randomized study. Blind versus open approach to laparoscopic cholecystectomy: a randomized study. Prospective randomized trial on low-pressure versus standard-pressure pneumoperitoneum in outpatient laparoscopic cholecystectomy. Is it necessary to lift the abdominal wall when preparing a pneumoperitoneum? A randomized study. Comparison between intraperitoneal CO2 insufflation and abdominal wall lift on QT dispersion and rate-corrected QT dispersion during laparoscopic cholecystectomy.
We have compared, in a randomized study, conventional carbon dioxide pneumoperitoneum with abdominal wall lift in 25 patients undergoing laparoscopic cholecystectomy. Intra-abdominal pressure (IAP) (11 (SD 2) mm Hg vs 2.7 (9) mm Hg) (P < 0.01) and total amount of carbon dioxide used (40 (23) litre vs 9 (7) litre) (P < 0.001) were significantly less with abdominal wall lift. Pulmonary compliance was significantly greater (P < 0.01) in the abdominal wall lift group throughout operation. During the first 15 min of insufflation, arterial pressures were lower with abdominal wall lift (P < 0.05). In the conventional pneumoperitoneum group, femoral vein pressure increased (P < 0.01) and remained elevated for 3 h in the recovery room. Postoperative drowsiness was of significantly longer duration in the conventional pneumoperitoneum group than in the abdominal wall lift group (98 (46) min vs 13 (34) min) (P < 0.01). Postoperative nausea and vomiting and right shoulder pain occurred more often in patients with conventional pneumoperitoneum (P < 0.05). We conclude that the benefits of abdominal wall lift may be attributed to avoiding excessive carbon dioxide and high IAP. Two alternative surgical techniques for elective laparoscopic cholecystectomy (LC), low-pressure insufflation of the peritoneal cavity and abdominal wall lifting (AWL), have been developed over time to minimize the disadvantages associated with CO2-elicited pneumoperitoneum. To the best of our knowledge, the 2 methods have seldom been compared as regards their relative advantages and disadvantages.
                Eighty patients scheduled for elective LC were randomized into either a low-pressure (8 mmHg) CO2 insufflation method (LPLC) group, or a gasless technique using a subcutaneous abdominal wall lifting device (GLC group). The duration of the surgical procedure, the surgical results including level of postoperative pain, and perioperative cardiopulmonary function changes experienced by the members of both groups were compared.
                Laparoscopic surgery was completed for all but 1 patient from each group due to an inadequate surgical-site exposure. There was no mortality for study participants, and no major complications were noted for members of either group. The LPLC group evidenced a shorter surgical duration as compared to the GLC group (77 +/- 28 minutes vs. 98 +/- 27 minutes, respectively; p < 0.01) and a lower incidence of postoperative shoulder pain (2/38 vs. 8/39, respectively; p < 0.05), although significant differences in intraoperative pulmonary function were noted (an increased PaCO2, Pet CO2 and peak-airway pressure and decreased arterial blood pH; p < 0.01) for the LPLC group compared to the GLC group.
                Both alternative methods for this type of surgery appeared feasible and safe for LC. Low-pressure CO2 pneumoperitoneum had a shorter surgical duration and less postoperative shoulder pain compared to the GLC technique, but did not feature any other advantage over the AWL technique with regard to impact on cardiopulmonary function. Gasless laparoscopy using abdominal wall lifting (AWL) has been developed in an attempt to avoid the adverse effects of carbon dioxide pneumoperitoneum that may occur in conventional laparoscopy. However, lifting has been criticized for its poor operative space and surgical invasiveness. This study compared the AWL method with conventional CO2 pneumoperitoneum for laparoscopic cholecystectomy with respect to operation performance, postoperative course, and stress response.
                During a 6-month period, 95 patients with symptomatic gallstones were randomly assigned to receive laparoscopic cholecystectomy with conventional CO2 pneumoperitoneum (CO2 group; N = 47) or the AWL method (AWL group; N = 48). Operative results and operative time were recorded. Cardiopulmonary functions were assessed, and arterial blood gases were analyzed during surgery. Urinary cortisol, vanillylmandelic acid, metanephrines, and nitrogen loss; serum complement 3, C-reactive protein, and interleukin-6; postoperative pain; and the presence of nausea and vomiting were assessed for 48 hours after surgery. Postoperative time to recovery of flatus, tolerance of a full oral diet, and full activity were also determined.
                Only three significant differences were found. First, intraoperative ventilatory function deteriorated significantly less in the AWL group. Second, arterial blood gas determinations and capnography showed a greater decrease in intraoperative arterial pH and compliance with CO2 retention and an increase in peak airway pressure in the CO2 group (P < 0.05), reflecting poorer ventilatory performance. Third, preparation time and total operating time were significantly greater with the AWL method (P < 0.05).
                Although AWL required a longer operation time, our results suggest that the technique may still have value in high-risk patients with cardiorespiratory diseases. To compare intraoperative cardiac function, postoperative cognitive recovery, and surgical performance of laparoscopic cholecystectomy with abdominal wall lift (AWL) versus positive-pressure capnoperitoneum (PPCpn).
                AWL has been proposed as an alternative approach to PPCpn to avoid adverse cardio-respiratory changes. However, the workspace obtained with the AWL is less optimal than PPCpn and previous studies documenting delayed postoperative recovery of consciousness following PPCpn have not assessed mental alertness despite its importance.
                Forty operations were randomized into AWL and PPCpn. A standard anesthetic protocol was followed. Cardiac indices were measured with an esophageal Doppler machine. An auditory vigilance test was used to measure alertness level following extubation. All operations were videotaped and human reliability assessment techniques were used to identify surgical errors.
                There was a significant reduction in cardiac output during the first 20 minutes following CO2 insufflation in the PPCpn group, whereas in the AWL group it did not exhibit any significant change. Patients in AWL arm had better vigilance scores at 90 and 180 minutes following extubation compared with the PPn group (P < 0.05). Significantly more surgical errors were observed during surgery with AWL than with PPCpn (7.1 +/- 1.1; versus 2.9 +/- 0.4; P = 0.001).
                The AWL approach avoids fall in cardiac output associated with PPCpn during laparoscopic surgery and is associated with a more rapid recovery of postoperative cognitive function compared with PPCpn. However, AWL increases the level of difficulty in the execution of the operation. Disadvantages related to CO2 pneumoperitoneum have led to development of the abdominal wall retractor (AWR), a device designed to facilitate laparoscopic surgery without conventional pneumoperitoneum (15 mmHg CO2). We investigated the effects of the AWR on hemodynamics and gas exchange in humans. We also investigated whether the use of an AWR imposed extra technical difficulties for the surgeon. A pilot study revealed that cholecystectomy without low-pressure pneumoperitoneum was technically impossible.
                A prospective randomized controlled trial: Twenty patients undergoing laparoscopic cholecystectomy were randomly allocated into group 1: AWR with low-pressure pneumoperitoneum (5 mmHg), or group 2: conventional pneumoperitoneum (15 mmHg).
                Surgery using the AWR lasted longer, 72 +/- 16 min (mean +/- SD) vs 50 +/- 18 min compared with standard laparoscopic cholecystectomy. There were no differences between the groups with respect to hemodynamic parameters, although a small reduction of the cardiac output was observed using conventional pneumoperitoneum (from 3.9 +/- 0.7 to 3. 2 +/- 1.1 l/min) and an increase during AWR (from 4.2 +/- 0.9 to 5.2 +/- 1.5 l/min). Peak inspiratory pressures were significantly higher during conventional pneumoperitoneum compared to AWR. A slight decrease in pH accompanied by an increase in CO2 developed during pneumoperitoneum and during the use of the AWR. In both groups arterial PO2 decreased.
                The results indicate that the view was impaired during use of the AWR and therefore its use was difficult and time-consuming. Possible advantages of this devices' effects on hemodynamics and ventilatory parameters could not be confirmed in this study. Because of absorbed carbon dioxide (CO(2)) and elevated intraabdominal pressure (IAP), CO(2) pneumoperitoneum (CO(2)PP) has potentially harmful intraoperative circulatory and ventilatory effects. Although not clinically significant for healthy patients, these effects are assumed to be deleterious for patients with a high risk for anesthesia (American Society of Anesthesiology [ASA] 3 and 4) and significant cardiopulmonary, renal, or hepatic diseases. The authors assessed CO(2)PP-related adverse effects by comparing ASA 3 and 4 patients who underwent laparoscopic cholecystectomy (LC) with or without CO(2)PP.
                A total of 20 successive ASA 3 and 4 patients who underwent LC were randomized into CO(2)PP (n = 10) and abdominal wall elevator (Laparolift) (n = 10) groups. The parameters for perioperative hemodynamics, ventilation, perfusion of intraabdominal organs, and blood chemistry were recorded periodically from before the induction of the anesthesia until postoperative day 2 and compared between the groups.
                Mean age, height, weight, the proportional number of ASA 3 vs ASA 4 patients, the volume of perioperative fluid loading, and the dose of analgesics did not differ significantly between the groups. The length of the operation was 49.9 +/- 10.6 min for the CO(2)PP group and 50.6 +/- 17.2 min for Laparolift group (nonsignificant difference). The mean central venous pressure (CVP) 30 min after insufflation was higher (12.3 +/- 4.8 vs 7.9 +/- 3.7 mmHg) and the (Gastric Mucosal pH) pHi at the end of the operation was lower (7.29 +/- 0.07 vs 7.35 +/- 0.04) in the CO(2)PP group than in the Laparolift group (p < 0.05). Later, CVP and pHi did not differ significantly. Other parameters of hemodynamics including oxygenation, perfusion, and blood chemistry did not differ significantly.
                For LC for patients with an ASA 3 and 4 risk for anesthesia, no significant adverse effects could be attributed to CO(2 )pneumoperitoneum. For high-risk patients, preoperative preparation and active perioperative monitoring are essential for safe anesthesia for LC with or without CO(2)PP. It has been shown repeatedly that laparoscopic cholecystectomy using pneumoperitoneum (CO2 insufflation) may be associated with increased cardiac filling pressures and an increase in blood pressure and systemic vascular resistance. In the present study, the effects on the central circulation during abdominal wall lift (a gasless method of laparoscopic cholecystectomy) were compared with those during pneumoperitoneum. The study was also aimed at elucidating the relationships between the central filling pressures and the intrathoracic pressure.
                Twenty patients (ASA I), scheduled for laparoscopic cholecystectomy, were randomised into two groups, pneumoperitoneum or abdominal wall lift. Measurements were made by arterial and pulmonary arterial catheterization before and during pneumoperitoneum or abdominal wall lift with the patient in the horizontal position. Measurements were repeated after head-up tilting the patients as well as after 30 min head-up tilt. The intrathoracic pressure was monitored in the horizontal position before and during intervention using an intraesophageal balloon.
                After pneumoperitoneum or abdominal wall lifting there were significant differences between the two groups regarding MAP, SVR, CVP, CI, and SV. Analogous to previous studies, in the pneumoperitoneum group CVP, PCWP, MPAP, and MAP as well as SVR were increased after CO2 insufflation (P < 0.01), while CI and SV were not affected. In contrast, in the abdominal wall lift group, CI and SV were significantly increased (P < 0.01), as was MAP (P < 0.01), while CVP, PCWP, MPAP, and SVR were not significantly affected. There was a significant difference in intraesophageal pressure between the two groups. In the pneumoperitoneum group, the intraesophageal pressure was increased by insufflation (P < 0.01) while, in the abdominal wall lift group, it was unaffected. In the pneumoperitoneum group the mean increases in cardiac filling pressures were of the same magnitude as the mean increase in the intraesophageal pressure.
                In healthy patients, abdominal wall lift increased cardiac index while pneumoperitoneum did not. Cardiac filling pressures and systemic vascular resistance were increased by pneumoperitoneum but unaffected by abdominal wall lift. The recorded elevated cardiac filling pressures during pneumoperitoneum may be only a reflection of the increased intra-abdominal pressure. Laparoscopic cholecystectomy using low-pressure pneumoperitoneum (8 mmHg) minimizes adverse hemodynamic effects, reduces postoperative pain, and accelerates recovery. Similar claims are made for gasless laparoscopy using abdominal wall lifting. The aim of this study was to compare gasless laparoscopic cholecystectomy to low-pressure cholecystectomy with respect to postoperative pain and recovery.
                Thirty-six patients were randomized to low-pressure or gasless laparoscopic cholecystectomy using a subcutaneous lifting system (Laparotenser).
                The characteristics of the patients were similar in the two groups. The procedure was completed in all patients in the low-pressure group, but two patients in the gasless group were converted to pneumoperitoneum. There were no significant differences in postoperative pain and analgesic consumption, but patients in the gasless group developed shoulder pain more frequently (50% vs 11%, p < 0.05). Gasless operation took longer to perform (95 vs 72.5 min, p = 0.01).
                Gasless and low-pressure laparoscopic cholecystectomy were similar with respect to postoperative pain and recovery. The gasless technique provided inferior exposure and the operation took longer, but the technique may still have value in high-risk patients with cardiorespiratory disease. Increase in plasma renin activity and noradrenaline concentration occur in response to carbon dioxide insufflation during laparoscopic cholecystectomy. In a randomized study the conventional carbon dioxide pneumoperitoneum was compared with the abdominal wall lift method for laparoscopic cholecystectomy, with special reference to neuroendocrine changes and renal function. The total mean(s.d.) volume of carbon dioxide insufflated was 42(23) litres with the conventional method and 9(7) litres with abdominal wall lift (P < 0.001). Mean(s.d.) intra-abdominal pressure after 15 min of insufflation was 11(2) and 3(9) mmHg respectively (P < 0.01). In the conventional group mean(s.d.) plasma renin activity increased slightly from 5.5(2.1) to 6.1(2.0) ng ml-1 during the first 55 min of laparoscopic cholecystectomy. In the abdominal wall lift group plasma renin activity decreased from 5.3(2.7) to 3.8(0.9) ng ml (P < 0.01 between the groups). Plasma antidiuretic hormone concentration increased similarly in both groups. Diuresis was significantly less with conventional pneumoperitoneum during the first 35 min of the operation compared with the abdominal wall lift method (P < 0.001). There were significant increases in plasma noradrenaline concentration in both groups (P < 0.001), but the increase was slightly higher in the conventional group during the first 15 min of insufflation. The abdominal wall lift method with minimal carbon dioxide insufflation was associated with smaller neuroendocrine responses and better preservation of renal function compared with conventional carbon dioxide pneumoperitoneum. Between April and August 1991, 83 Japanese patients with symptomatic gallstones underwent laparoscopic cholecystectomy in our clinics. A prospective randomized trial was carried out to examine the safety, efficacy, and complications of the two techniques, pneumoperitoneum vs an elevating method using a U-shaped retractor. Forty-two patients were randomly allocated to the pneumoperitoneum (P) group and 41 to the U-shaped retractor (U) group. These two groups were well matched with respect to age, sex, etiology, and the severity of the chronic cholecystitis. Laparoscopic resection was successful for 88.1% (37/42) in the P group and 100% (41/41) in the U group. In patients with a severe fibrotic gallbladder, the rate of success was significantly higher (P < 0.05) in the U group (100%, 6/6) than in the P group (11.8%, 1/6). In the moderately inflamed group, the operation time (mean +/- SD) was significantly (P < 0.01) less in the U group (58.7 +/- 22.7) than in the P group (87.3 +/- 18.3). With the U-shaped retractor the usual surgical instruments can be used, and a rapid and safer laparoscopic cholecystectomy can be carried out. We prefer this approach to a pneumoperitoneum for patients with an inflamed gallbladder as hospital stay and pain are minimal. Impairments in hemodynamics during pneumoperitoneum (PP) have been noted. This study compared changes in hemodynamics and surgical stress response with PP and abdominal wall lifting (AWL) during laparoscopic cholecystectomy.
                Twenty patients with symptomatic cholecystolithiasis were assigned to PP (n = 10) or AWL (n = 10). Cardiac output (CO), stroke volume (SV), and ejection fraction (%EF) were measured by transesophageal echocardiography. Clearances of para-aminohippurate (CPAH) and sodium thiosulfate (CSTS) were determined as measures of renal function. Levels of interleukin-6, C-reactive protein, white cell count, and neutrophil elastase were evaluated as indicators of surgical stress.
                In the PP group, CO, SV, and %EF were depressed significantly during pneumoperitoneum. Immediately after and 15 min after insufflation, the CPAH and CSTS were decreased by 78.0% and 73.8%, respectively. None of the hemodynamic parameters changed significantly in the AWL group. Surgical stress response was not different significantly between the two groups.
                In contrast to pneumoperitoneum, AWL did not alter cardiac function or renal hemodynamics. AWL may be useful in patients with cardiovascular or renal disorders. Although abdominal wall retraction is said to be advantageous in laparoscopic cholecystectomy (LC), many surgeons have found that, when this option is chosen, more time is needed to prepare for and carry out the surgical procedure. Our aim was to determine the time required for surgical preparation and operation in patients undergoing LC with carbon dioxide (CO2) pneumoperitoneum (CO2 PP) vs abdominal wall retraction (AWR).
                We performed a prospective randomized study of a CO2 PP LC group (n = 19) vs an AWR LC group (n = 15). Demographic data were collected preoperatively. LC was performed with either CO2 PP (12 mmHg) or AWR (6-10 kps). Two phases were considered: (a) time employed to create the surgical field (phase 1) and (b) operating time (phase 2). The chi-square test was used to compare the medians of the two groups.
                The two groups were homogeneous. Phase 1 required 35 min in the CO2 PP group vs 25 min in the AWR group (p = 0.24). Phase 2 required 60 min in both groups (p = 0.76).
                We found no statistically significant difference between the PP CO2 and AWR groups in either time spent to create the surgical field or actual operating time. Carbon dioxide (CO2) pneumoperitoneum together with an increased intraabdominal pressure (IAP) induces a hemodynamic stress response, diminishes urine output, and may compromise splanchnic perfusion. A new retractor method may be less traumatic. Accordingly, 30 ASA physical status I or II patients undergoing laparoscopic cholecystectomy were randomly allocated to a CO2 pneumoperitoneum (IAP 12-13 mm Hg) (control) or to a gasless abdominal wall lift method (retractor) group. Anesthesia and intravascular fluids were standardized. Direct mean arterial pressure (MAP), urine output, urine-N-acetyl-beta-D-glucosaminidase (U-NAG), arterial blood gases, gastric mucosal PCO2, and intramucosal pH (pHi) were measured. Normoventilation was instituted in all patients. MAP increased (P < 0.001) only with CO2 pneumoperitoneum. Minute volume of ventilation had to be increased by 35% with CO2 insufflation. PaCO2 was significantly higher (P < 0.05) for 3 h postoperatively in the control group. Diuresis was less (P < 0.01) and U-NAG levels (P < 0.01) higher in the control group. The pHi decreased after induction of pneumoperitoneum up to three hours postoperatively and remained intact in the retractor group. We conclude that the retractor method for laparoscopic cholecystectomy ensures stable hemodynamics, prevents respiratory acidosis, and provides protection against biochemical effects, which reveal the renal and splanchic ischemia caused by CO2 insufflation. Implications: A mechanical retractor method (gasless) was compared with conventional CO2 pneumoperitoneum for laparoscopic cholestectomy. The gasless method ensured stable hemodynamics, prevented respiratory acidosis, and provided protection against the renal and splanchnic ischemia seen with CO2 pneumoperitoneum. The fact that pulmonary complications occur in 20-60% of the patients subjected to abdominal operations clearly indicates that the lungs are the most endangered organ during the postoperative period.
                The aim of this study was to demonstrate the impact of cholecystectomy on postoperative respiratory disturbances by comparing the laparotomic cholecystectomy with laparoscopic gallbladder removal.
                A hundred cholecystectomized patients were included in the prospective randomized clinical trial. Half of the patients were operated on by the laparotomic procedure, whereas the other half underwent laparoscopic cholecystectomy. Spirometric parameters, arterial blood gases, and acid-base balance were determined before the operation, and at 6, 24, 72 and 144 h postoperatively. Abdominal distension was assessed by auscultating intestinal peristaltics, abdominal circumference measurement, and time interval to restitution of defecation.
                Six hours postoperatively, the values of ventilation parameters decreased on average by 40-50% from the baseline preoperative values in both groups of patients. The group of patients submitted to laparotomic cholecystectomy had significantly lower spirometric values and slower recovery of the ventilation parameters than the laparoscopic cholecystectomy group. Abdominal circumference was significantly greater and the time needed for restitution of peristaltics and defecation was significantly longer in the laparotomic cholecystectomy group compared to the group of laparoscopic cholecystectomy.
                Statistically significant impairments including hypoxia, hypocapnia and hyperventilation were observed in the patients submitted to laparotomic cholecystectomy, indicating the presence of objective respiratory risk, especially in elderly patients and patients with obstructive pulmonary diseases or cardiac insufficiency.
                Copyright 2000 S. Karger AG, Basel Changes in blood hormone and cytokine were investigated in patients who underwent laparoscopic cholecystectomy via insufflation (CO2 group) vs those who had abdominal wall-lifting (Air group).
                Seventeen female patients with cholecystolithiasis were randomly divided into two groups. Peripheral blood samples were obtained during perioperative period, and plasma hormone levels (ACTH, cortisol) and serum cytokine levels (TNFalpha, IL-1beta, IL-6, IL-10) were measured.
                The number of circulating lymphocytes significantly decreased at 1 h after surgery in both groups, but the decrease in the CO2 group was significantly smaller than that in the Air group. There was no significant difference in hormone elevation between groups. Serum concentrations of IL-6 and IL-10 in the Air group were significantly higher than in the CO2 group.
                CO2 insufflation may reduce cytokine production in laparoscopic cholecystectomy. Carbon dioxide (CO2) pneumoperitoneum effects are still controversial. The aim of this study was to investigate cardiopulmonary changes in patients subjected to different surgical procedures for cholecystectomy.
                In this study, 15 patients were assigned randomly to three groups according to the surgical procedure to be used: open cholecystectomy (OC), CO2 pneumoperitoneum cholecystectomy (PP), and laparoscopic gasless cholecystectomy (abdominal wall lifting [AWL]), respectively. A pulmonary artery catheter was used for hemodynamic monitoring in all patients. A subcutaneous multiplanar device (Laparo Tenser) was used for abdominal wall lifting. To avoid misinterpretation of results, conventional anesthesia was performed with all parameters, and the position of the patients held fixed throughout surgery. The following parameters were analyzed: mean arterial pressure (MAP), heart rate (HR), cardiac output (CO), cardiac index (CI), stroke volume index (SVI), central venous pressure (CVP), systemic vascular resistances index (SVRI), mean pulmonary arterial pressure (MPAP), pulmonary capillary wedge pressure (PCWP), pulmonary vascular resistances index (PVRI), peak inspiratory pressure (PIP), end-tidal CO2 pressure (ETCO)2, CO2 arterial pressure (PaCO2), and arterial pH.
                All the operations were completed successfully. The Laparo Tenser allowed good exposition of the surgical field. A slight impairment of the cardiopulmonary functions, with reduction of SVRI, MAP, and CI and elevation of pulmonary pressures and vascular resistance, followed induction of anesthesia. However, these effects tended to normalize in the OC and AWL groups over time. In contrast, CO2 insufflation produced a complex hemodynamic and pulmonary syndrome resulting in increased right- and left side filling pressures, significant cardiac index reduction, derangement of the respiratory mechanics, and respiratory acidosis. All of these effects normalized after desufflation.
                Cardiopulmonary adverse effects of general anesthesia were significant but transitory and normalized during surgery. Carbon dioxide pneumoperitoneum caused a significant impairment in cardiopulmonary functions. In high-risk patients, gasless laparoscopy may be preferred for reliability and absence of cardiopulmonary alterations. Intraabdominal structures may be damaged during blind introduction of the first trocar for laparoscopic operations. In this study, 150 patients with gallbladder lithiasis who underwent laparoscopy were randomly assigned to two groups, a blind (V group) or an open (H group), in order to compare the results and the rate of complications. No mortality was observed. Major complications occurred in 3/75 (4%) patients of the V group and in 1/75 (1.3%) patient of the H group (p < 0.05). Minor complications occurred in 5/75 (6.7%) patients of either group. The achievement of pneumoperitoneum required 4.5+/-0.4 min in the V group and 3.2+/-0.2 min in the H group (p < 0.05). The open laparoscopic technique is safer and faster than the blind approach; therefore, it is proposed that this approach be routinely used in all laparoscopic procedures. Inpatient low-pressure pneumoperitoneum laparoscopic cholecystectomy (LPLC) has been shown to have less postoperative pain (especially shoulder-tip pain). No report so far has documented the use of lower-pressure pneumoperitoneum in outpatient laparoscopic cholecystectomy (LC). A prospective randomized trial was conducted in Tung Wah Hospital, Day Surgery Centre from January 2004 to December 2004. A total of 40 patients were recruited and 20 of whom were allocated to each arm. Outcome measures included operation time, treatment-related morbidity, mortality, postoperative pain (eg, shoulder-tip pain), consumption of analgesics, and level of satisfaction. All patients in both groups could be discharged on the same day. Patients' demographics and operation time were comparable in both groups. There were no treatment-related morbidity and mortality, nor was there any significant difference in postoperative pain. Less shoulder-tip pain was observed in the LPLC group though without significant difference (5% vs. 20%; P=0.151). Three patients in the LPLC group needed higher insufflation pressure (12 mm Hg) because of inadequate exposure and adhesions, and the operations were successful in all of them. Otherwise, no conversion to open procedure was noted in both groups. The consumption of analgesics was minimal and a high level of satisfaction was achieved in both groups of patients. The present study demonstrated no difference in LPLC and standard-pressure pneumoperitoneum laparoscopic cholecystectomy in the outcomes of outpatient LC. Routine use of lower-pressure pneumoperitoneum in outpatient LC would not be recommended unless in selected straightforward cases. In order to create a pneumoperitoneum with the Veress needle, it is generally advocated that the abdominal wall should be lifted. Lifting is aimed at increasing the distance between the abdominal wall and the intraabdominal structures. This study was conducted to compare lifting (L) and nonlifting (NL) of the abdominal wall.
                All patients scheduled for laparoscopic surgery without previous abdominal surgery or morbid obesity were included in the study group. The number of attempts needed for proper positioning of the needle was assessed.
                A total of 150 patients were randomized. There were no complications. The number of attempts needed for correct positioning of the Veress needle was significantly higher in the L group than in the NL group (31 of 75 vs nine of 75, p < 0.001). The body mass index (BMI) of patients in whom peritoneal entry needed more than one puncture was significantly higher than the BMI of patients with immediate proper placement (28.3 vs 24.7 kg/m(2), p < 0.05).
                Abdominal wall lifting is not necessary. This study compared the effect of intraperitoneal CO2 insufflation with abdominal wall lift on RR interval, QT interval, the rate-corrected QT (QTc) interval, QT dispersion (QTD), and the rate-corrected QTD (QTcD) using computerized measurement during laparoscopic cholecystectomy. Thirty patients scheduled for laparoscopic cholecystectomy were randomly assigned to 2 groups: intraperitoneal CO2 insufflation (CO2 group) or abdominal wall lift (lift group). A 12-lead electrocardiogram was monitored to measure parameters. The RR interval, QT interval, and QTc interval did not change significantly during the study in both groups. The QTD and QTcD in the CO2 group increased significantly during CO2 insufflation, and were significantly higher than those of the lift group. Statistically significant increases of QTD and QTcD, which are associated with an increased risk of arrhythmias and cardiac events, occur during CO2 insufflation, and QTD and QTcD in the CO2 group were significantly higher than those of the lift group.
Abdominal wall lift does not seem to offer an advantage over pneumoperitoneum in any of the patient-oriented outcomes for laparoscopic cholecystectomy in patients with low anaesthetic risk. It may increase costs by increasing the operating time. Hence it cannot be recommended routinely. The safety of abdominal wall lift is yet to be established. More research on the topic is needed because of the risk of bias in the included trials and because of the risk of type I and type II random errors because of the few patients included in the trials. Such trials ought to include patients at higher anaesthetic risk. Furthermore, such trials ought to include blinded assessment of outcome measures.