Crit Care Med

Artificial nutrition after major abdominal surgery: impact of route of administration and composition of the diet.

Braga M. Gianotti L. Vignali A. Cestari A. Bisagni P. Di Carlo V.
Department of Surgery, Scientific Institute San Raffaele, University of Milan, Italy.
OBJECTIVE: To evaluate the impact of the route of administration of artificial nutrition and the composition of the diet on outcome. DESIGN: Prospective, randomized, clinical trial. SETTING: Department of surgery, university hospital. PATIENTS: One hundred sixty-six consecutive patients undergoing curative surgery for gastric or pancreatic cancer. INTERVENTIONS: At operation, the patients were randomized into three groups to receive: a) a standard enteral formula (control group; n = 55); b) the same enteral formula enriched with arginine, RNA, and omega-3 fatty acids (enriched group; n = 55); and c) total parenteral nutrition (TPN group; n = 56). The three regimens were isocaloric and isonitrogenous. Enteral nutrition was started within 12 hrs following surgery. The infusion rate was progressively increased to reach the nutritional goal (25 kcal/kg/day) on postoperative day 4. MEASUREMENTS AND MAIN RESULTS: Tolerance of enteral feeding, rate and severity of postoperative complications, and length of hospital stay were recorded. Early enteral infusion was well tolerated. Side effects were recorded in 22.7% of the patients, but only 6.3% did not reach the nutritional goal. The enriched group had a lower severity of infection than the parenteral group (4.0 vs. 8.6; p < .05). In subgroups of malnourished (n = 78) and homologous transfused patients (n = 42), the administration of the enriched formula significantly reduced both severity of infection and length of stay compared with the parenteral group (p < .05). Moreover, in transfused patients, the rate of septic complications was 20.0% in the enriched group, 38.4% in the control group, and 42.8% in the TPN group. CONCLUSIONS: Early enteral feeding is a suitable alternative to TPN after major abdominal surgery. The use of the enriched diet appears to be more beneficial in malnourished and transfused patients.

Removal of piperacillin in critically ill patients undergoing continuous venovenous hemofiltration.

Capellier G. Cornette C. Boillot A. Guinchard C. Jacques T. Blasco G. Barale F.
Centre Hospitalier Universitaire Jean Minjoz, Faculte de Pharmacie, Besancon, France.
OBJECTIVE: Continuous hemofiltration is now widely used in the intensive care unit. Our study aimed to assess the removal of piperacillin under continuous hemofiltration and to define a suitable dosage regimen of administration. DESIGN: Prospective study of blood and ultrafiltrate concentrations of piperacillin to assess the pharmacokinetics of the antibiotic. SETTING: The medical intensive care unit of a teaching hospital. PATIENTS: Ten patients were included in the study. Six patients were receiving their first dose of piperacillin (group 1) and four had already been treated for 2 to 6 days (group 2). The mean Simplified Acute Physiology II score was 74 +/- 6 (SEM), and the number of organ failures was 3.6 +/- 0.3 (range 3 to 5). Renal failure was related to septic shock in seven patients and to cardiogenic shock in three patients. Seven patients were anuric. Hepatic dysfunction was present in four of the ten patients. INTERVENTIONS: Patients were treated with continuous venovenous hemofiltration using a hollow polysulfone capillary fiber. Piperacillin (4 g) was injected intravenously over 20 mins. Arterial blood and ultrafiltrate were sampled immediately before the injection and then every hour until 8 hrs after injection time. Piperacillin concentrations were assayed using high performance liquid chromatography. MEASUREMENTS AND MAIN RESULTS: In group 1, the mean serum peak concentration of piperacillin was in the normal range (125 +/- 21 mg/L), but trough values were higher (48 +/- 8 mg/L) than in normal subjects. In group 2, trough values before the injection were increased in all patients (188 +/- 71 mg/L). At T1, blood peak concentration reached 470 +/- 127 mg/L. A small amount of piperacillin was retrieved from the ultrafiltrate. The elimination half-life was 5.1 +/- 1.4 and 4.8 +/- 1.4 hrs in groups 1 and 2, respectively. CONCLUSIONS: Piperacillin was not removed to a significant extent during continuous hemofiltration. Further, in the intensive care unit, patients in shock with multiple organ failure such as liver failure might behave differently from patients with stable end-stage renal disease. A 4-g dose of piperacillin twice a day is recommended in such patients.

Earlier identification of patients at risk from acetaminophen-induced acute liver failure.

Mitchell I. Bihari D. Chang R. Wendon J. Williams R.
Institute of Liver Studies, King's College Hospital, London, UK.
OBJECTIVE: To determine whether the Acute Physiology and Chronic Health Evaluation (APACHE) II system for the measurement of severity of illness is able to provide an accurate risk of hospital death in patients with acetaminophen-induced acute liver failure or identify those patients needing transfer for possible hepatic transplantation. DESIGN: Data for admission (first 24 hrs) APACHE II scores and King's criteria for urgent transplantation were collected prospectively to compare the APACHE II system and the King's criteria for the prediction of death or need for transplantation. SETTING: A nine-bed specialist liver failure unit (LFU). PATIENTS: One hundred two consecutive patients admitted to the LFU with acetaminophen self-poisoning and a prolonged prothrombin time were studied. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: An APACHE II score of > 15 points was associated with a high mortality (13/20 patients, five of whom survived following hepatic transplantation). There was no relation between APACHE II risk and outcome (mean APACHE II risk of death 0.8%, actual hospital mortality 16%). An APACHE II score of > 15 had a similar power of prediction of death as the King's criteria (sensitivity 82% and 65%, respectively; specificity 98% and 99%, respectively), when considering those patients who were transplanted as "deaths." An APACHE II score of > 15 was able to identify four more patients than the King's criteria on the first day of admission to the LFU. CONCLUSIONS: The crude admission APACHE II score correlated well with mortality in patients with acetaminophen-induced acute liver failure. However, the calculated APACHE II risk of death, using the original drug overdose coefficient, was poorly calibrated. Since specialist liver scores are unfamiliar in the general intensive care setting, the use of an APACHE II score might earlier identify more patients at risk of needing a liver transplant, and hence, expedite appropriate transfer to a specialist liver unit.

Prospective evaluation of surfactant composition in bronchoalveolar lavage fluid of infants with congenital diaphragmatic hernia and of age-matched controls.

Year 1998
IJsselstijn H. Zimmermann LJ. Bunt JE. de Jongste JC. Tibboel D.
Department of Pediatric Surgery, Erasmus University and University Hospital/Sophia Children's Hospital, Rotterdam, The Netherlands.
OBJECTIVES: Infants with congenital diaphragmatic hernia may have biochemically immature lungs. However, normal lecithin/sphingomyelin ratios and phosphatidylglycerol concentrations have been reported in the amniotic fluid of congenital diaphragmatic hernia patients. We hypothesized that if the lungs of congenital diaphragmatic hernia patients are surfactant deficient, that this condition would be reflected in an altered surfactant composition in the bronchoalveolar lavage fluid compared with that composition in age-matched controls. DESIGN: Prospective, controlled study. SETTING: Surgical intensive care unit in a Level III pediatric university hospital. PATIENTS: Four groups were studied: two groups of congenital diaphragmatic hernia patients (conventionally ventilated, n = 13; treated with extracorporeal membrane oxygenation, n = 5); and two control groups (conventionally ventilated, n = 13; extracorporeal membrane oxygenation, n = 6). INTERVENTIONS: Bronchoalveolar lavage, using a blind, standardized technique, was performed in conventionally ventilated congenital diaphragmatic hernia patients, extracorporeal membrane oxygenation-treated congenital diaphragmatic hernia patients, age-matched conventionally ventilated controls without pulmonary abnormalities, and extracorporeal membrane oxygenation-treated infants without congenital diaphragmatic hernia. MEASUREMENTS AND MAIN RESULTS: The concentrations of different surfactant phospholipids and the fatty acid composition of phosphatidylcholine in bronchoalveolar lavage fluid were measured. No significant differences between the concentrations of phosphatidylcholine and phosphatidylglycerol, and the lecithin/sphingomyelin ratios, were found between the four groups. The fatty acid composition of phosphatidylcholine in conventionally ventilated patients showed a median percentage of palmitic acid within the normal range for age in both groups: 68% in congenital diaphragmatic hernia patients and 73% in controls (p < .001). CONCLUSIONS: Our findings indicate that the concentrations of different phospholipids are similar in congenital diaphragmatic hernia patients and controls without congenital diaphragmatic hernia. A primary surfactant deficiency is unlikely in infants with congenital diaphragmatic hernia. However, secondary surfactant deficiency after respiratory failure may be involved.

Obstructive shock due to labor-related diaphragmatic hernia.

Year 1998
Ortega-Carnicer J. Ambros A. Alcazar R.
Intensive Care Unit, Hospital Alarcos, Ciudad Real, Spain.
OBJECTIVE: To report diaphragmatic hernia as a cause of obstructive shock in the peripartum period. DESIGN: Case report. SETTING: An adult, 12-bed medical/surgical intensive care unit of a general hospital. PATIENTS: One patient who developed an obstructive shock following vaginal labor and was transferred under mechanical ventilation from a local hospital. INTERVENTIONS: Central venous pressure, blood pressure, blood gas analysis, electrocardiogram, and chest radiograph during and after obstructive shock. MEASUREMENTS AND MAIN RESULTS: During shock, systolic blood pressure was 60 mm Hg, central venous pressure was +12 mm Hg, and the electrocardiogram showed a supraventricular tachycardia and an acute cor pulmonale pattern. Chest radiograph showed signs of left diaphragmatic hernia and right mediastinal shift. Chest ultrasound examination demonstrated loops of bowel in the left pleural space. After surgical resolution of the left diaphragmatic hernia, the patient's blood pressure increased to 120/80 mm Hg, the central venous pressure decreased to +1 mm Hg, and the PaO2 increased to 154 torr (20.5 kPa) while receiving mechanical ventilation with an FiO2 of 50%. The electrocardiogram showed disappearance of the acute cor pulmonale pattern. The chest radiograph showed a central venous catheter located in a persistent left superior vena cava without abnormalities of the diaphragm, the mediastinum, or the lung. CONCLUSION: Diaphragmatic hernia must be included in the differential diagnosis of obstructive shock in pregnant patients.

How to use a review article: prophylactic endoscopic sclerotherapy for esophageal varices. Evidence Based Critical Care Medicine Group.

Year 1998
Cook DJ. Levy MM. Heyland DK.
Department of Medicine, McMaster University, Hamilton, ON, Canada.
OBJECTIVE: To assess the validity of a meta-analysis about sclerotherapy for the primary prevention of bleeding from esophageal varices, to interpret the results, and discuss whether they apply in practice. DATA SOURCES: Critical appraisal techniques for systematic reviews. DATA EXTRACTION: Systematic reviews are distinct from narrative reviews in that they answer specific clinical questions, and have explicit and reproducible methods for searching, selecting, and appraising the primary studies, to create the most valid synthesis of the evidence. DATA SYNTHESIS: Meta-analyses are systematic reviews containing a critical appraisal and statistical summary of individual study results and their confidence limits, whereas qualitative systematic reviews provide a narrative executive summary of study results. CONCLUSIONS: High-quality systematic reviews are being used increasingly to guide practice, strengthening the link between research results and improved health outcomes. Understanding their strengths and limitations helps us to use them appropriately in practice.

Removal of endotoxin and cytokines by plasma exchange in patients with acute hepatic failure.

Year 1998
Iwai H. Nagaki M. Naito T. Ishiki Y. Murakami N. Sugihara J. Muto Y. Moriwaki H.
First Department of Internal Medicine, Gifu University School of Medicine, Japan.
OBJECTIVES: To compare the circulating concentrations of endotoxin and cytokines in patients with fulminant hepatitis and patients with the severe form of acute hepatitis, and to assess the effects of plasma exchange on the circulating concentrations of these inflammatory mediators in patients with acute hepatic failure. DESIGN: Prospective, consecutive entry study of patients meeting fulminant hepatitis criteria and the severe form of acute hepatitis criteria. SETTING: University hospital, intensive care unit. PATIENTS: Five patients with fulminant hepatitis, eight patients with the severe form of acute hepatitis, two patients with acute-on-chronic hepatic failure, and one patient with postoperative hepatic failure. INTERVENTIONS: Plasma endotoxin, serum tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and IL-6 were determined on admission in five patients with fulminant hepatitis and eight patients with the severe form of acute hepatitis. Circulating concentrations of the inflammatory mediators were measured before and after a single course of plasma exchange in eight patients with acute liver failure, including five patients with fulminant hepatitis, two patients with acute-on-chronic hepatic failure, and one patient with postoperative hepatic failure. MEASUREMENTS AND MAIN RESULTS: TNF-alpha and IL-6 in patients with fulminant hepatitis were significantly higher than in patients with the severe form of acute hepatitis, whereas endotoxin concentrations did not differ between patients with fulminant hepatitis or the severe form of acute hepatitis. IL-1beta was not detectable in patients with either fulminant hepatitis or the severe form of acute hepatitis. Plasma endotoxin concentrations decreased immediately after plasma exchange. Serum concentrations of TNF-alpha and IL-6 were significantly lower after plasma exchange than before plasma exchange. CONCLUSION: TNF-alpha and IL-6 may be important in the pathogenesis of the clinical symptoms that differentiate fulminant hepatitis from the severe form of acute hepatitis, and plasma exchange removes these inflammatory mediators from the circulation of patients with severe liver disease.