Optimizing peroperative compliance with PEEP during upper abdominal surgery: effects on perioperative oxygenation and complications in patients without preoperative cardiopulmonary dysfunction. Intraoperative ventilatory strategies for prevention of pulmonary atelectasis in obese patients undergoing laparoscopic bariatric surgery. Postoperative arterial oxygen tension after peroperative PEEP-ventilation. Efficacy of positive end-expiratory pressure titration after the alveolar recruitment manoeuvre in patients with acute respiratory distress syndrome. Does prophylactic administration of systemic antibiotics prevent postoperative inflammatory complications after third molar surgery? Immediate postoperative enteral feeding results in impaired respiratory mechanics and decreased mobility. Minimal access surgery for cholelithiasis induces an attenuated acute phase response.
Late postoperative hypoxaemia after upper abdominal surgery is common even among cardiopulmonary healthy patients. Atelectasis may develop after intubation and persist into or reveal a disposition for atelectasis in the postoperative period. Positive end-expiratory pressure (PEEP) eliminates peroperative atelectasis but the effect on perioperative oxygenation is controversial. This study evaluated the effect of peroperative PEEP optimized pulmonary compliance on perioperative oxygenation and complications.
                Forty patients assessed by electrocardiography, spirometry, functional residual capacity and diffusion capacity were randomly assigned to receive positive end-expiratory pressure (PEEP) or zero end-expiratory pressure (ZEEP) during surgery. PaO2, SPO2 and complications in the postoperative period were evaluated without knowledge of peroperative PEEP or ZEEP application.
                Peroperative arterial oxygenation improved for all patients receiving PEEP, mean 2.1 kPa (0.7-3.5 kPa). There was no difference in postoperative median PaO2 between the groups. The differences in the incidence of late prolonged postoperative hypoxaemia and complications were 25% (-5% to 55%) and -1% (-31% to 29%) between the ZEEP and the PEEP group, but were not statistically significant. Atelectasis occurs regularly after induction of general anesthesia, persists postoperatively, and may contribute to significant postoperative morbidity and additional health care costs. Laparoscopic surgery has been reported to be associated with an increased incidence of postoperative atelectasis. It has been shown that during general anesthesia, obese patients have a greater risk of atelectasis than nonobese patients. Preventing atelectasis is important for all patients but is especially important when caring for obese patients.
                We randomly allocated 66 adult obese patients with a body mass index between 30 and 50 kg/m(2) scheduled to undergo laparoscopic bariatric surgery into 3 groups. According to the recruitment maneuver used, the zero end-expiratory pressure (ZEEP) group (n = 22) received the vital capacity maneuver (VCM) maintained for 7-8 s applied immediately after intubation plus ZEEP; the positive end-expiratory pressure (PEEP) 5 group (n = 22) received the VCM maintained for 7-8 s applied immediately after intubation plus 5 cm H(2)O of PEEP; and the PEEP 10 group (n = 22) received the VCM maintained for 7-8 s applied immediately after intubation plus 10 cm H(2)O of PEEP. All other variables (e.g., anesthetic and surgical techniques) were the same for all patients. Heart rate, noninvasive mean arterial blood pressure, arterial oxygen saturation, and alveolar-arterial Pao(2) gradient (A-a Pao(2)) were measured intraoperatively and postoperatively in the postanesthesia care unit (PACU). Length of stay in the PACU and the use of a nonrebreathing O(2) mask (100% Fio(2)) or reintubation were also recorded. A computed tomographic scan of the chest was performed preoperatively and postoperatively after discharge from the PACU to evaluate lung atelectasis.
                Patients in the PEEP 10 group had better oxygenation both intraoperatively and postoperatively in the PACU, lower atelectasis score on chest computed tomographic scan, and less postoperative pulmonary complications than the ZEEP and PEEP 5 groups. There was no evidence of barotrauma in any patient in the 3 study groups.
                Intraoperative alveolar recruitment with a VCM followed by PEEP 10 cm H(2)O is effective at preventing lung atelectasis and is associated with better oxygenation, shorter PACU stay, and fewer pulmonary complications in the postoperative period in obese patients undergoing laparoscopic bariatric surgery. Forty otherwise healthy patients (29 women and 11 men), undergoing elective cholecystectomy, were randomly allocated to be ventilated during the operation either with a positive end-expiratory pressure of 1 kPa (10 cmH2O) (PEEP group) or with intermittent positive pressure ventilation without PEEP (control group). During the operation the mean arterial oxygen tension (PaO2) in the PEEP group increased from 14.6 to 16.5 kPa, while no changes occurred in the control group (13.5 and 13.6 kPa). On the first postoperative day, PaO2 decreased by 12% of the preoperative values in the PEEP group; the decrease was 20% in the control group. On the third postoperative day, the PaO2 in the control group was still 9% below the preoperative values, but on the fifth day, both groups had reached their preoperative PaO2 values. In the postoperative period, no statistically significant difference in PaO2 could be demonstrated between the groups. Determinations of the forced vital capacity and forced expiratory volume in the first second showed no difference between the groups pre- or postoperatively. The present study demonstrated no clinically relevant beneficial effect of peroperative PEEP ventilation on the postoperative arterial hypoxaemia after an upper abdominal laparotomy. In acute respiratory distress syndrome (ARDS), adequate positive end-expiratory pressure (PEEP) may decrease ventilator-induced lung injury by minimising overinflation and cyclic recruitment-derecruitment of the lung. We evaluated whether setting the PEEP using decremental PEEP titration after an alveolar recruitment manoeuvre (ARM) affects the clinical outcome in patients with ARDS.
                Fifty-seven patients with early ARDS were randomly assigned to a group given decremental PEEP titration following ARM or a table-based PEEP (control) group. PEEP and inspired fraction of oxygen (FiO2) in the control group were set according to the table-based combinations of FiO2 and PEEP of the ARDS network, by which we aimed to achieve a PEEP level compatible with an oxygenation target. In the decremental PEEP titration group, the oxygen saturation and static compliance were monitored as the patients performed the ARM along with the extended sigh method, which is designed to gradually apply and withdraw a high distending pressure over a prolonged period, and the decremental titration of PEEP.
                The baseline characteristics did not differ significantly between the control and decremental PEEP titration groups. Initial oxygenation improved more in the decremental PEEP titration group than in the control group. However, dynamic compliance, tidal volume and PEEP were similar in the two groups during the first week. The duration of use of paralysing or sedative agents, mechanical ventilation, stay in the intensive care unit and mortality at 28 days did not differ significantly between the decremental PEEP titration and control groups.
                The daily decremental PEEP titration after ARM showed only initial oxygenation improvement compared with the table-based PEEP method. Respiratory mechanics and patient outcomes did not differ between the decremental PEEP titration and control groups.
                ClinicalTrials.gov identifier: ISRCTN79027921. To estimate and compare the frequencies of inflammatory complications after third molar (M3) surgery in subjects receiving intravenous prophylactic antibiotics or saline placebo.
                Using a placebo-controlled, double-blind, randomized clinical trial, the investigators enrolled a sample composed of subjects who required extraction of at least 1 impacted M3 and requested intravenous sedation or general anesthesia. The predictor variable was treatment group classified as active treatment (penicillin or clindamycin for penicillin-allergic subjects) or placebo (0.9% saline). Study medications were randomly assigned. Both surgeon and subject were blinded to treatment assignment. The medication was administered intravenously prior to any incision. The outcome variable was postoperative inflammatory complication classified as present or absent and included alveolar osteitis (AO) or surgical site infection (SSI). Other variables were demographic, anatomic, or operative. Descriptive and bivariate statistics were computed. Statistical significance was set at P < or = .05, single-tailed test of hypothesis.
                The sample was composed of 118 subjects (n = 59 per study group). In the active treatment group, there were no postoperative inflammatory complications. In the placebo group, 5 subjects (8.5%) were diagnosed with SSI, (P = .03). No subject met the case definition for AO. All SSIs were associated with the removal of partial bony or full bony impacted mandibular M3s.
                In the setting of third molar removal, these results suggest that the use of intravenous antibiotics administered prophylactically decrease the frequency of SSIs. The authors cannot comment on the efficacy of intravenous antibiotics in comparison to other antibacterial treatment regimens, eg chlorhexidine mouthrinse or intrasocket antibiotics. The authors set out to determine whether immediate enteral feeding minimizes early postoperative decreases in handgrip and respiratory muscle strength.
                Muscle strength decreases considerably after major surgical procedures. Enteral feeding has been shown to restore strength rapidly in other clinical settings.
                A randomized, controlled, nonblinded clinical trial was conducted in patients undergoing esophagectomy or pancreatoduodenectomy who received immediate postoperative enteral feeding via jejunostomy (fed, n = 13), or no enteral feeding during the first 6 postoperative days (unfed, n = 15). Handgrip strength, vital capacity, forced expiratory volume in one second (FEV1), and maximal inspiratory pressure (MIP) were measured before surgery and on postoperative days 2, 4, and 6. Fatigue and vigor were evaluated before surgery and on postoperative day 6. Mobility was assessed daily after surgery using a standardized descriptive scale. Postoperative urine biochemistry was evaluated in daily 24-hour collections.
                Postoperative vital capacity (p < 0.05) and FEV1 (p = 0.07) were consistently lower (18%-29%) in the fed group than in the unfed group, whereas grip strength and maximal inspiratory pressure were not significantly different. Postoperative mobility also was lower in the fed patients (p < 0.05) and tended to recover less rapidly (p = 0.07). Fatigue increased and vigor decreased after surgery (both p < or = 0.001), but changes were similar in the fed and unfed groups. Intensive care unit and postoperative hospital stay did not differ between groups.
                Immediate postoperative jejunal feeding was associated with impaired respiratory mechanics and postoperative mobility and did not influence the loss of muscle strength or the increase in fatigue, which occurred after major surgery. Immediate postoperative enteral feeding should not be routine in well-nourished patients at low risk of nutrition-related complications. Some benefits of laparoscopic (LC) and minilaparotomy (MC) cholecystectomy may reflect attenuation of the acute phase response. The authors examined components of this response.
                Patients were randomized to LC (n = 11) or MC (n = 11). C-reactive protein (CRP), alpha-1-antitrypsin (AAT), retinol-binding protein (RBP), transferrin, and albumin were measured preoperatively and on postoperative days 1, 2, 4, and 7. Interleukin-1 receptor antagonist (IL-1ra), IL-6, and tumor necrosis factor (TNF-alpha) were measured more frequently perioperatively. Peak expiratory flow rate, forced expiratory volume in 1 second, and forced vital capacity were measured daily.
                The IL-6 increase was more persistent and marked in the MC patients from hour 8 to day 7 postoperatively (P < 0.05). Alterations in CRP, AAT, and albumin were similar. Postoperative deficits of respiratory function correlated with the magnitude of acute phase protein alteration.
                Minimal access surgery induces an acute phase response that is less prominent after a laparoscopic technique.
There is currently insufficient evidence to make conclusions about whether intraoperative PEEP alters the risk of postoperative mortality and respiratory complications among undifferentiated surgical patients.