Effect of postpyloric feeding on gastroesophageal regurgitation and pulmonary microaspiration: results of a randomized controlled trial.

OBJECTIVE: To determine the extent to which postpyloric feeding reduces gastroesophageal regurgitation and pulmonary microaspiration in critically ill patients. DESIGN: Randomized trial. SETTING: A medical/surgical intensive care unit at a tertiary care hospital. PARTICIPANTS: Intensive care unit patients were expected to remain ventilated >72 hrs. We excluded patients with esophageal, gastric, or small bowel surgery in the last week and patients with overt or clinically significant gastrointestinal bleeding. We studied 33 patients; 42.4% were female, mean age (sd) was 59.2 (+/- 16.8) yrs, and mean Acute Physiology and Chronic Health Evaluation II score was 22.5 (7.8). INTERVENTIONS: Patients were randomized to gastric or postpyloric enteral feeds. Technetium 99-sulphur colloid was added to the feeds for 6 hrs of each of the first 3 days on study. MEASUREMENTS AND RESULTS: We sampled the oropharynx and trachea hourly for the 6 hrs per day that patients received radioisotope-labeled enteral feeds, and the level of radioactivity in these specimens was measured. We defined an episode of gastroesophageal regurgitation and microaspiration as an increase in radioactivity >100 counts per minute/g. Patients fed into the stomach had more episodes of gastroesophageal regurgitation (39.8% vs. 24.9%, p =.04) and trended toward more microaspiration (7.5% vs. 3.9%, p =.22) compared with patients fed beyond the pylorus. When the logarithmic mean of the radioactivity count was compared across groups, there was a trend toward an increase in gastroesophageal regurgitation (3.7 vs. 2.9 counts/g, p =.22) and a trend toward increased microaspiration (1.9 vs. 1.4 counts/g, p =.09) in patients fed into the stomach. Patients who had gastroesophageal regurgitation were much more likely to aspirate than patients who did not have gastroesophageal regurgitation (odds ratio: 3.2; 95% confidence interval: 1.36, 7.77). CONCLUSIONS: Feeding beyond the pylorus is associated with a significant reduction in gastroesophageal regurgitation and a trend toward less microaspiration.

Capnography confirms correct feeding tube placement in intensive care unit patients.

PURPOSE: To test the accuracy and potential time savings of capnography as compared with a two-step radiographic method in placing feeding tubes in critically ill patients. METHODS: One hundred feeding tube placements were studied in our tertiary care intensive care unit. All placements utilized a two-step radiographic method, but capnography was added to the procedure. The procedure was then completed or abandoned depending on radiographic interpretation. RESULTS: Radiography showed 11 feeding tubes projecting within the tracheobronchial tree. In all 11 of these placements, the capnography unit displayed a normal capnogram. Radiography revealed 86 tube placements in the midesophageal region. In all 86 of these placements, capnography displayed a "purging warning". In three placements, radiography indicated that the tube was coiled in the oropharynx. In these cases, the capnograph displayed one "no purging/no capnogram" result, and two "purging" warnings. If using capnography alone, an average of 72.5 min would be required to complete a feeding tube placement (which includes time for requisite "pre-feed radiograph"). The two-step radiological approach took an average of 169.4 min, a difference of 96.9 min (P <0.0001) between the two methods. CONCLUSIONS: Capnography accurately identified all intratracheal feeding tube placements in this study. This study also shows that the use of capnography would significantly shorten the time needed for tube placement compared with a two-step radiologic method. Capnography should be considered for routine use when placing feeding tubes since it adds little time to the procedure and may improve patient safety.

Should immunonutrition become routine in critically ill patients? A systematic review of the evidence.

CONTEXT: Several nutrients have been shown to influence immunologic and inflammatory responses in humans. Whether these effects translate into an improvement in clinical outcomes in critically ill patients remains unclear. OBJECTIVE: To examine the relationship between enteral nutrition supplemented with immune-enhancing nutrients and infectious complications and mortality rates in critically ill patients. DATA SOURCES: The databases of MEDLINE, EMBASE, Biosis, and CINAHL were searched for articles published from 1990 to 2000. Additional data sources included the Cochrane Controlled Trials Register from 1990 to 2000, personal files, abstract proceedings, and relevant reference lists of articles identified by database review. STUDY SELECTION: A total of 326 titles, abstracts, and articles were reviewed. Primary studies were included if they were randomized trials of critically ill or surgical patients that evaluated the effect of enteral nutrition supplemented with some combination of arginine, glutamine, nucleotides, and omega-3 fatty acids on infectious complication and mortality rates compared with standard enteral nutrition, and included clinically important outcomes, such as mortality. DATA EXTRACTION: Methodological quality of individual studies was scored and necessary data were abstracted in duplicate and independently. DATA SYNTHESIS: Twenty-two randomized trials with a total of 2419 patients compared the use of immunonutrition with standard enteral nutrition in surgical and critically ill patients. With respect to mortality, immunonutrition was associated with a pooled risk ratio (RR) of 1.10 (95% confidence interval [CI], 0.93-1.31). Immunonutrition was associated with lower infectious complications (RR, 0.66; 95% CI, 0.54-0.80). Since there was significant heterogeneity across studies, we examined several a priori subgroup analyses. We found that studies using commercial formulas with high arginine content were associated with a significant reduction in infectious complications and a trend toward a lower mortality rate compared with other immune-enhancing diets. Studies of surgical patients were associated with a significant reduction in infectious complication rates compared with studies of critically ill patients. In studies of critically ill patients, studies with a high-quality score were associated with increased mortality and a significant reduction in infectious complication rates compared with studies with a low-quality score. CONCLUSION: Immunonutrition may decrease infectious complication rates but it is not associated with an overall mortality advantage. However, the treatment effect varies depending on the intervention, the patient population, and the methodological quality of the study.

Total parenteral nutrition in the surgical patient: a meta-analysis.

OBJECTIVE: To examine the relationship between total parenteral nutrition(TPN) and complication and death rates in surgical patients. DATA SOURCES: A computer search of published research on MEDLINE, personal files and a review of relevant reference lists. STUDY SELECTION: A review of 237 titles, abstracts or papers. Primary studies were included if they were randomized clinical trials of surgical patients that evaluated the effect of TPN (compared to no TPN or standard care) on complication and death rates. Studies comparing TPN to enteral nutrition (EN) were excluded. DATA EXTRACTION: Relevant data were abstracted on the methodology and outcomes of primary studies. Data were independently abstracted in duplicate. DATA SYNTHESIS: There were 27 randomized trials in surgical patients that compared the use of TPN to standard care (usual oral diet plus intravenous dextrose). When the results of these trials were aggregated, there was no effect on mortality (risk ratio = 0.97, 95% confidence intervals, 0.76 to 1.24). There were fewer major complications in patients who received TPN, although there was significant heterogeneity in the overall estimate (risk ratio = 0.81, 95% CI, 0.65 to 1.01). Because of this significant heterogeneity, several a priori hypotheses were examined. Studies that included only malnourished patients demonstrated a trend to a reduction in complication rates but no difference in death rate when compared with studies of patients who were not malnourished. Studies published in 1988 or earlier and studies with a lower methods score were associated with a significant reduction in complication rates and a trend to a reduction in death rate when compared with studies published after 1988 and studies with a higher methods score. There was no difference in studies that provided lipids as a component of TPN when compared with studies that did not. Studies that initiated TPN preoperatively demonstrated a trend to a reduction in complication rates but no difference in death rate when compared with studies that initiated TPN postoperatively. CONCLUSIONS: TPN does not influence the death rate of surgical patients. It may reduce the complication rate, especially in malnourished patients, but study results are influenced by methodologic quality and year of publication.

Total parenteral nutrition in the critically ill patient: a meta-analysis.

CONTEXT: Nutritional support has become a standard of care for hospitalized patients, but whether total parenteral nutrition (TPN) affects morbidity and mortality is unclear. OBJECTIVE: To examine the relationship between TPN and complication and mortality rates in critically ill patients. DATA SOURCES: Computerized search of published research on MEDLINE from 1980 to 1998, personal files, and review of relevant reference lists. STUDY SELECTION: We reviewed 210 titles, abstracts, and papers. Primary studies were included if they were randomized clinical trials of critically ill or surgical patients that evaluated the effect of TPN (compared with standard care) on complication and mortality rates. We excluded studies comparing TPN with enteral nutrition. DATA EXTRACTION: Relevant data were abstracted on the methodology and outcomes of primary studies. Data were abstracted in duplicate, independently. DATA SYNTHESIS: There were 26 randomized trials of 2211 patients comparing the use of TPN with standard care (usual oral diet plus intravenous dextrose) in surgical and critically ill patients. When the results of these trials were aggregated, TPN had no effect on mortality (risk ratio [RR], 1.03; 95% confidence interval [CI], 0.81-1.31). Patients who received TPN tended to have a lower complication rate, but this result was not statistically significant (RR, 0.84; 95% CI, 0.64-1.09). We examined several a priori hypotheses and found that studies including only malnourished patients were associated with lower complication rates but no difference in mortality when compared with studies of nonmalnourished patients. Studies published since 1989 and studies with a higher methods score showed no treatment effect, while studies published in 1988 or before and studies with a lower methods score demonstrated a significant treatment effect. Complication rates were lower in studies that did not use lipids; however, there was no difference in mortality rates between studies that did not use lipids and those studies that did. Studies limited to critically ill patients demonstrated a significant increase in complication and mortality rates compared with studies of surgical patients. CONCLUSIONS: Total parenteral nutrition does not influence the overall mortality rate of surgical or critically ill patients. It may reduce the complication rate, especially in malnourished patients, but study results are influenced by patient population, use of lipids, methodological quality, and year of publication.

Laparoscopic cholecystectomy in a patient with situs inversus viscerum: a case report.

A patient with known situs inversus viscerum of the abdomen and congenital heart disease presented with symptomatic cholelithiasis in a left-sided gallbladder. Laparoscopic cholecystectomy was carried out successfully, despite the reversed anatomic relationships, and the patient made a smooth recovery. This is the first case report of a successful laparoscopic cholecystectomy in a patient with a left-sided gallbladder.

Initiation of parturition in humans.

The mechanism by which parturition is initiated in humans is largely unknown. The placenta and fetal membranes appear to play the major role in the initiation of labour, and the fetus may influence the timing of labour. Clinical observations and experiments with animals have revealed that placental neuropeptides may be able to control steroid metabolism and trigger the onset of labour, while the fetus may be able to interact with such events to initiate parturition at an appropriate time. However, further study is needed to determine the role of placental releasing factors and glycoprotein hormones and their ability to control placental steroid metabolism.