Antibiotic prophylaxis before surgery vs after cord clamping in elective cesarean delivery: a double-blind, prospective, randomized, placebo-controlled trial.

CONTEXT: Perioperative antibiotic prophylaxis during elective cesarean delivery at term to reduce postoperative maternal infectious morbidity is generally used but may not be effective on the basis of the available data. Also, the optimal timing of prophylactic antibiotic administration is unclear. OBJECTIVE: To compare the effectiveness of cefazolin administered before skin incision vs cefazolin administered after umbilical cord clamping vs placebo in a 3-arm randomized trial. The primary objective of the study was to compare postoperative infectious morbidity, defined as wound infection, endometritis, or urinary tract infection (primary end point), in women with cefazolin vs placebo. The comparison between the 2 arms administering cefazolin before skin incision vs after umbilical cord clamping was a secondary end point. DESIGN: Double-blind, prospective, randomized, placebo-controlled trial. SETTING: The Department of Obstetrics and Gynecology, Medical University of Vienna, Vienna, Austria. PATIENTS: We recruited 1112 women undergoing elective cesarean delivery at term from March 1, 2004, through January 31, 2010. INTERVENTIONS: In group 1, cefazolin (2 g) was administered 20 to 30 minutes before skin incision. In group 2, cefazolin (2 g) was administered immediately after clamping of the cord. In group 3, placebo was administered before skin incision. RESULTS: The primary outcome was observed in 18 of 370 women in group 1 (4.9%) and in 14 of 371 women in group 2 (3.8%), whereas it was noted in 45 of 371 women in group 3 (12.1%) (P < .001 for group 1 plus group 2 vs group 3). The number needed to treat to avoid 1 primary outcome was 13 (95% CI, 9 to 24). Between groups 1 and 2, there was no statistically significant difference regarding postoperative infectious morbidity (P = .60). CONCLUSION: We were able to demonstrate the usefulness in elective cesarean delivery of prophylactic cefazolin vs placebo in reducing postoperative maternal infectious morbidity.

Impact of initial and boundary conditions on preferential flow.

Preferential flow in soil is approached by a water-content wave, WCW, that proceeds downward from the ground surface. WCWs were obtained from sprinkler experiments with infiltration rates varying from 5 to 40 mm h(-1). TDR-probes and tensiometers measured volumetric water contents theta(z,t) at seven depths, and capillary heads, h(z,t) at six depths in a column of an undisturbed soil. The wave is characterized by the velocity of the wetting front, c(W), the amplitude, w(S), and the final water content, theta*. We tested with uni-variate and bi-variate linear regressions the impacts of initial volumetric water contents, theta(ini), and input rates, q(S), on c(W), w(S) and theta*. The test showed that theta(ini) influenced theta* and w(S) and q(S) effected c(W). The expected proportionality of w(S) approximately = qs(1/3) was weak and c(W) approximately = qs(2/3) was strong.

Incidence of complications in intrahospital transport of critically ill patients--experience in an Austrian university hospital.

BACKGROUND: During the past decade, considerable changes and advances have been made in intrahospital transport of critically ill patients. Despite the fact that intrahospital transport is nowadays regarded an extension of the intensive care continuum, it still poses a risk for the patient. MATERIALS AND METHODS: This prospective, observational study was designed to determine the occurrence rate of transport-related complications in the altered setting of intrahospital transports and to identify possible confounding sources of increased risk. In an eight-month period, adults and infants from anesthesiologic intensive care units were analyzed. RESULTS: A total of 226 patients underwent 452 intrahospital transports. The overall rate of critical incidents was low (4.2%) and no direct association between mortality and intrahospital transport was observed. In addition to the known risk factors of ventilatory support with positive end-expiratory pressure and requirement for catecholamine support, the necessity for intrahospital transport in the acute vs. elective situation was found to significantly increase the risk of complications. CONCLUSIONS: We conclude that advances in the management of intrahospital transport of critically ill patients have led to an overall decrease of complications. However, an undeniable risk remains, especially in relation to disease severity and the urgency of such transports.

Infusion of increasing doses of endotoxin induces progressive acute lung injury but prevents early pulmonary hypertension in pigs.

Administration of a single bolus of endotoxin is a model of sepsis response in experimental animal studies. Large animal species, such as pigs and sheep, are more sensitive to endotoxin administration due to an initial excessive pulmonary hypertensive response frequently resulting in acute right heart dysfunction. We investigated whether infusion of high-dose endotoxin in pigs but administered in an increasing dose results in inflammatory response without excessive pulmonary hypertension and right heart dysfunction. Piglets of both sexes weighing 25 to 30 kg were anesthetized and mechanically ventilated. After instrumentation and baseline measurements, animals received an infusion of total 500 microg kg(-1) i.v. endotoxin (Escherichia coli LPS) over 2 h in an increasing dose of 0.5 to 12 microg kg(-1) min(-1). Hemodynamic, respiratory, and oxygenation parameters were measured every hour. At 1 and 5 h following endotoxin, plasma levels of inflammatory and organ damage parameters were measured. Endotoxin infusion induced progressive arterial hypoxemia, an increase in peak inspiratory pressure, sustained pulmonary hypertension, and systemic hypotension that persisted throughout the experiment. Endotoxin plasma levels peaked at 1 h following infusion and declined toward baseline values at 5 h thereafter. In contrast, plasma levels of nitrite/nitrate, IL-1ra (as marker of cytokine response), remained markedly increased at 5 h after endotoxin infusion as compared with baseline values. Plasma markers of organ damage were significantly increased. Our data show that the dosing of endotoxin in an increasing manner in pigs produces a reliable model of an experimental sepsis response and organ dysfunction without immediate overwhelming pulmonary hypertension resulting in cardiovascular failure.

Dynamic CT measurement of pulmonary enhancement in piglets with experimental acute respiratory distress syndrome.

PURPOSE: To investigate whether analysis of a washout curve of contrast material obtained with serial computed tomography (CT) enables differentiation between hydrostatic pulmonary edema and pulmonary edema caused by increased capillary permeability. MATERIALS AND METHODS: The institutional committee on animal experiments approved this study, which was performed in accordance with designated guidelines. Chest CT was performed in 12 piglets after induction of anesthesia and start of mechanical ventilation. Dynamic CT was performed before and after induction of hydrostatic edema (n = 5) or oleic acid-induced increased vascular permeability edema (n = 7). Scans were obtained over 240 seconds during inspiratory breath holding at a single representative subcarinal level in the lungs. This anatomic level was kept constant and included areas of normal ventilation before and after induction of pulmonary edema and areas of ground-glass opacity and consolidation after induction of pulmonary edema. Measured lung attenuation in the regions of interest was normalized to that before contrast material injection and plotted as a function of time. Statistical analysis was performed by using two-way analysis of variance with repeated measures. RESULTS: In general, before induction of pulmonary edema, attenuation of normally aerated lung areas did not increase after the initial peak of enhancement during the first pass of contrast material. In animals with hydrostatic edema, no attenuation changes in areas of ground-glass opacity were observed after the initial peak. Conversely, lung attenuation increased continuously in animals with oleic acid-induced high-permeability pulmonary edema (P = .002). After induction of lung edema, pulmonary enhancement measured in lung regions with normal ventilation or consolidation did not change in either group. Pulmonary fluid accumulation 90 minutes after induction of edema did not significantly differ between groups. CONCLUSION: Dynamic contrast-material enhanced CT can help differentiate between permeability and hydrostatic lung edema in an animal model.

Inhaled nitric oxide therapy in adults: European expert recommendations.

BACKGROUND: Inhaled nitric oxide (iNO) has been used for treatment of acute respiratory failure and pulmonary hypertension since 1991 in adult patients in the perioperative setting and in critical care. METHODS: This contribution assesses evidence for the use of iNO in this population as presented to a expert group jointly organised by the European Society of Intensive Care Medicine and the European Association of Cardiothoracic Anaesthesiologists. CONCLUSIONS: Expert recommendations on the use of iNO in adults were agreed on following presentation of the evidence at the expert meeting held in June 2004.

Effects of carbon monoxide inhalation during experimental endotoxemia in humans.

Data show that carbon monoxide (CO) exerts direct antiinflammatory effects in vitro and in vivo after LPS challenge in a mouse model. We hypothesized that CO may act as an antiinflammatory agent in human endotoxemia. The aim of this trial was to study the effects of CO inhalation on cytokine production during experimental human endotoxemia. The main study was a randomized, double-blinded, placebo-controlled, two-way cross-over trial in healthy volunteers. Each volunteer inhaled synthetic air (as placebo) and 500 ppm CO for 1 hour in random order with a washout period of 6 weeks and received a 2-ng/kg intravenous bolus of LPS after inhalation. Carboxyhemoglobin levels were assessed as a safety parameter. CO inhalation increased carboxyhemoglobin levels from 1.2% (95% confidence interval, 1.0 to 1.4%) to peak values of 7.0% (95% confidence interval, 6.5 to 7.7%). LPS infusion transiently increased plasma concentrations of tumor necrosis factor-alpha, interleukin (IL)-6 (approximately 150-fold increases), and IL-8, as well as IL-1alpha and IL-1beta mRNA levels (an approximately 200-fold increase). These LPS-induced changes were not influenced by CO inhalation. Inhalation of 500 ppm CO for 1 hour had no antiinflammatory effects in a systemic inflammation model in humans, as 250 ppm for 1 hour did in rodents.

Liver support in fulminant liver failure after hemorrhagic shock.

Acute liver failure (ALF) is a rare clinical syndrome associated with a mortality of up to 80% and its management remains an interdisciplinary challenge. Despite recent improvements in intensive care management, the mortality of patients with ALF remains high and is related to complications such as cerebral edema, sepsis and multiple organ failure. Emergency orthotopic liver transplantation (OLT) is currently the only effective treatment for those patients who are unlikely to recover spontaneously. Nevertheless, OLT is not always possible because of the shortage of the organs and/or complications related to ALF. Newly introduced liver-assist devices can temporarily support the patient's liver until native liver recovers or can serve as a bridging device until a liver graft is available. The support devices use both cell-based and non-cell-based techniques. One of the latest non-cell-based extracorporeal hepatic support devices, the molecular adsorbent recycling system (MARS), is based on the concept of albumin dialysis. MARS utilises selective hemodiafiltration with countercurrent albumin dialysis aiming to selectively remove both water-soluble and albumin-bound toxins of the low and middle molecular-weight range. We report on a young patient who presented with clinical symptoms of ischemic hepatitis and multi-organ failure (APACHE II score 38-->predicted postoperative mortality 87%) due to prolonged hemorrhagic shock. OLT was contraindicated because of history of pancreas cancer with metastases. It was necessary to use aggressive conservative therapy and an extracorporeal liver-assist device until liver regeneration began and hemodynamic conditions were stable. The patient underwent five treatments with MARS. During the treatment, there were improvements of hemodynamics, respiratory function, acid-base disturbances and laboratory parameters. The plasma disappearance rate of indocyanine green, a parameter of dynamic liver function, improved during MARS treatment. Although repeated neurological examination predicted diffuse brain damage (brain oedema, decreased cerebral blood flow), the patient recovered without any neurological deficits. The patient survived and was discharged from the hospital in good condition. In this case MARS treatment was successful in supporting the patient through the most critical period of ALF.