Bedside diagnostic laparoscopy and peritoneal lavage in the intensive care unit

BACKGROUND

Early diagnosis and treatment of intra-abdominal pathology in critically ill intensive care unit (ICU) patients remains a clinical challenge. The objective of this study is to assess the feasibility of portable, bedside diagnostic laparoscopy (DL) in the ICU for patients suspected of intra-abdominal pathology, and to contrast its accuracy with diagnostic peritoneal lavage (DPL).

METHODS

All adult ICU patients for whom a general surgery consultation was requested were eligible. Patients with a recent laparotomy or obvious peritonitis were excluded. All procedures were performed in the ICU.

RESULTS

Over a consecutive 16-month period, 12 patients underwent DPL/DL. Ages ranged from 28 to 88 (mean, 72) years. Causative findings were disclosed by DL in five patients, (42%) including intestinal ischemia in two. Perforated diverticulitis, thickened terminal ileum, and nonpurulent peritonitis were found in one patient each. All patients with findings by DL had a positive DPL (WBC > 200 cells/mm3), and one negative laparoscopy was positive by lavage. The average length of time to perform DPL was 14 min, and to complete DL 19 min. One patient underwent laparotomy based on DPL/DL and survived along with three others with negative DPL/DL. Eight patients died (67%), four from their surgically untreated intra-abdominal pathology. One patient sustained a procedure-related complication of bradycardia and high ventilatory airway pressures. Peak airway pressures increased an average of 8 mmHg and were significantly higher (p < 0. 001) than pre-DL pressures without any significant change in end-tidal CO2 or pCO2. There were no statistically significant hemodynamic changes based on mean arterial pressure (MAP), central venous pressure (CVP), or pulmonary artery diastolic pressure (PADP).

CONCLUSIONS

Bedside laparoscopy can be performed rapidly and safely in the ICU. In predicting the need for laparotomy, DL was more accurate than DPL.

Interaction of aglycosyl immunoglobulins with the IgG Fc transport receptor from neonatal rat gut: comparison of deglycosylation by tunicamycin treatment and genetic engineering

The role of carbohydrate in the structure and function of immuno-globulin Fc regions has been studied using the interaction of a monoclonal mouse IgG2b anti-NIP antibody with the IgG Fc transport receptor from neonatal rat gut. An aglycosyl variant of this immunoglobulin, in which site-directed mutagenesis had been used to eliminate the carbohydrate attachment site in the CH2 domain by changing Asn297 to Ala, was compared in this system to aglycosyl immunoglobulin prepared from immunoglobulin-secreting cells treated with tunicamycin to inhibit N-linked glycosylation. Loss of carbohydrate from the heavy chain was confirmed for both methods by Western blotting of the separated chains with Concanavalin A, and no significant differences in circular dichroism spectra were found between glycosylated and non-glycosylated mutants. Removal of carbohydrate by site-directed mutagenesis had no effect on binding of the immunoglobulin to the Fc transport receptor (FcTR) in vitro or transport from the gut to blood in vivo. Short-term clearance from circulation and degradation by gut contents in vitro were similarly unaffected. Mutation of Glu235 to Leu, an alteration that allows binding to human monocyte Fc gamma RI, did not alter the interaction with FcTR. However, treatment of wild-type or aglycosyl mutant cells with tunicamycin resulted in immunoglobulin which was less stable, cleared more rapidly and was transported slightly less efficiently. These findings indicate that the binding site for the FcTR may be unique among Fc-binding ligands, and that tunicamycin treatment may cause alterations in the immunoglobulin molecule in addition to loss of N-linked carbohydrate.

Recovery of fish oil-derived fatty acids in lymph of thoracic duct-cannulated Wistar rats

The absorption of equivalent doses of eicosapentaenoic and docosahexaenoic acids was compared in rats when administered as the ethyl ester concentrate, ethyl ester concentrate plus olive oil, free fatty acid or triacylglycerol (menhaden oil). Lymph was collected from a thoracic duct cannula for 24 hr after dosing via an indwelling duodenal catheter. After 24 hr, the absorption of eicosapentaenoic acid was greater for the free fatty acid and menhaden oil than for the ethyl ester form, but docosahexaenoic acid absorption was comparable for all forms. Other rats had greater plasma levels of eicosapentaenoic and docosahexaenoic acids 5 hr after oral gavage dosing with menhaden oil than did rats dosed with the ethyl ester form.