Postoperative pulmonary complications (PPCs) occur frequently and are associated with substantial morbidity and mortality. Evidence suggests that reduction of PPCs can be accomplished by using lung-protective ventilation strategies intraoperatively, but a consensus on perioperative management has not been established. We sought to determine recommendations for lung protection for the surgical patient at an international consensus development conference. Seven experts produced 24 questions concerning preoperative assessment and intraoperative mechanical ventilation for patients at risk of developing PPCs. Six researchers assessed the literature using questions as a framework for their review. The modified Delphi method was utilised by a team of experts to produce recommendations and statements from study questions. An expert consensus was reached for 22 recommendations and four statements. The following are the highlights: (i) a dedicated score should be used for preoperative pulmonary risk evaluation; and (ii) an individualised mechanical ventilation may improve the mechanics of breathing and respiratory function, and prevent PPCs. The ventilator should initially be set to a tidal volume of 6-8 ml kg-1 predicted body weight and positive end-expiratory pressure (PEEP) 5 cm H2O. PEEP should be individualised thereafter. When recruitment manoeuvres are performed, the lowest effective pressure and shortest effective time or fewest number of breaths should be used.

In three clinical centres, we compared a new method for measuring cardiac output with conventional thermodilution. The new method computes beat-to-beat cardiac output from radial artery pressure by simulating a three-element model of aortic input impedance, and includes non-linear aortic mechanical properties and a self-adapting systemic vascular resistance. We compared cardiac output by continuous model simulation (MF) with thermodilution cardiac output (TD) in 54 patients (18 female, 36 male) undergoing coronary artery bypass surgery. We made three or four conventional thermodilution estimates spread equally over the ventilatory cycle. In 490 series of measurements, thermodilution cardiac output ranged from 2.1 to 9.3, mean 5.0 litre min(-1). MF differed +0.32 (1.0) litre min(-1) on average with limits of agreement of -1.68 and +2.32 litre min(-1). Differences decreased when the first series of measurements in a patient was used to calibrate the model. In 436 remaining series, the mean difference became -0.13 (0.47) litre min(-1) with limits of agreement of -1.05 and +0.79 litre min(-1). When consecutive measurements were made, the change was greater than 0.5 litre min(-1), on 204 occasions. The direction of change was the same with both methods in 199. The difference between the methods remained near zero during surgery suggesting that a single calibration per patient was adequate. Aortic model simulation with radial artery pressure as input reliably monitors changes in cardiac output in cardiac surgery patients. Before calibration, the model cannot replace thermodilution, but after calibration the model method can quantitatively replace further thermodilution estimates.

In 40 patients, the cardiovascular effects of low- and high-dose propofol anesthesia (single bolus of 1.5 mg/kg in group A, 2.5 mg/kg in group C) were examined and compared with those of low- and high-dose thiopental (4 mg/kg in group B, 6.5 mg/kg in group D) (n = 10 patients per group). After induction of anesthesia with etomidate, all patients were ventilated with 70% nitrous oxide in oxygen. Peripheral arterial systolic blood pressure (SAP) and transesophageal echocardiographic short-axis measurements were used to calculate the end-systolic pressure-volume relationship (E) as an index of global myocardial contractility. In all groups SAP decreased significantly below baseline levels for the duration of the measurements (15 min after drug administration), except for the lower dose of thiopental, where SAP returned to baseline values within 10 min. Propofol at a dose of 1.5 mg/kg significantly decreased cardiac output (CO) (from 5.1 +/- 0.25 [mean +/- SEM] to 4.2 +/- 0.23 L/min), stroke volume (SV) (from 64 +/- 3 to 56 +/- 3.6 mL), and the slope of E (from 71 +/- 3.5 to 65 +/- 4.2 mm Hg/mL) until 4 min after drug administration. The higher dose of propofol significantly decreased CO (from 5.1 +/- 0.29 to 4.1 +/- 0.26 L/min), SV (from 64 +/- 3 to 52 +/- 4.6 mL), and the slope of E (from 71 +/- 3.6 to 62 +/- 3.7 mm Hg/mL) until 10 min after drug administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Background Various techniques of laparoscopic Roux-en-Y gastric bypass have been described. We completely standardized this procedure to minimize its sometimes substantial morbidity and mortality. This study describes our experience with the standardized fully stapled laparoscopic Roux-en-Y gastric bypass (FS-LRYGB) and its influence on the 30-day morbidity and mortality. Methods We retrospectively analyzed 2,645 patients who underwent FS-LRYGB from May 2004 to August 2008. Operative time, hospital stay and readmission, re-operation, and 30-day morbidity/mortality rates were then calculated. The 30-day follow-up data were complete for 2,606 patients (98.5%). Results There were 539 male and 2,067 female patients. Mean age was 39.2 years (range 14–73), mean BMI 41.44 kg/m² (range, 23–75.5). The mean hospital stay was 3.35 days (range 2–71). Mean total operative time was 63 min (range 35–150). One patient died of pneumonia within 30 days of surgery (0.04%). One hundred and fifty one (5.8%) patients had postoperative complications as follows: gastrointestinal hemorrhage (n = 89, 3.42%), intestinal obstruction (n = 9, 0.35%), anastomotic leak (n = 5, 0.19%) and others (n = 47, 1.80%). In 66 patients, the bleeding resolved without any surgical re-intervention. One hemorrhage resulted in hypovolemic shock with subsequent renal and hepatic failure. Conclusion The systematic approach and the full standardization of the FS-LRYGB procedure contribute highly to the very low mortality and the low morbidity rates in our institution. Gastrointestinal bleeding appears to be the commonest complication, but is self-limiting in the majority of cases. Our approach also significantly reduces operative time and turns the technically demanding laparoscopic Roux-en-Y gastric bypass procedure into an easy reproducible operation, effective for training.