A critical comparison of the hematologic, cardiovascular, and pulmonary response to steroids and nonsteroidal anti-inflammatory drugs in a model of sepsis and adult respiratory distress syndrome.

Improved survival of patients receiving high-dose steroid therapy in sepsis and adult respiratory distress syndrome (ARDS) has been reported, but such therapy and its benefits remain controversial. Recently research has been directed toward manipulation of the arachidonic acid cascade. Improved survival and hemodynamics with administration of nonsteroidal anti-inflammatory drugs (NSAID) have been reported in animal models of sepsis and ARDS. The purpose of this study was to compare the effects of steroids (methylprednisolone) and NSAID (ibuprofen) in a porcine model of septic ARDS induced by a continuous infusion of live Pseudomonas aeruginosa. Cardiopulmonary parameters were monitored in animals intubated, paralyzed, and ventilated at a 250 ml tidal volume and 0.5 Fio2. Pigs were randomly assigned to one of five groups: groups I and II received respective doses of 12.5 mg/kg ibuprofen and 30 mg/kg methylprednisolone at 20 and 210 minutes after baseline; group III had P. aeruginosa only; groups IV and V received respective doses of ibuprofen and methylprednisolone at 20 and 210 minutes of sepsis. Significant pulmonary edema, increased intrapulmonary shunting, hypoxemia, hemoconcentration, and systemic hypotension occurred with P. aeruginosa infusion. In septic animals treated with ibuprofen normal systemic arterial pressure was maintained, hemoconcentration was decreased, and oxygenation was improved with a significant decrease in shunting and pulmonary edema. Administration of methylprednisolone improved hemoconcentration and cardiac index, but no significant effect on pulmonary edema, intrapulmonary shunting, or oxygenation was observed. The results of this study demonstrated a significant beneficial effect of ibuprofen and we would encourage controlled clinical trials of this drug in the management of sepsis and ARDS. On the other hand, methylprednisolone was found to be relatively ineffective in treatment of circulatory collapse and ARDS associated with sepsis.

Effect of positive end-expiratory pressure on extravascular lung water in porcine acute respiratory failure.

Recent studies of acute respiratory failure suggest that PEEP causes increased pulmonary interstitial fluid collection and therefore increased extravascular lung water (EVLW). We examined the effect of increasing levels of PEEP on EVLW in 20 to 25-kg pigs with acute respiratory failure induced by continuous infusion of live Pseudomonas aeruginosa (2 X 10(8) organisms/20 kg.min). Animals were intubated, paralyzed, and ventilated at 15 ml/kg tidal volume and an FIO2 of 0.4. Pigs in group 1 were given 4 ml/kg.h of iv fluid (lactated Ringer's solution) with no PEEP administered. Animals in groups 2 through 5 were given 0, 4, 17, and 44 ml/kg.h of lactated Ringer's solution, respectively, and PEEP was added at 5-cm H2O increments per half-hour, starting one hour after beginning P. aeruginosa infusion. EVLW in PEEP animals was less than or equal to that in controls despite variation in the administration of lactated Ringer's solution. This suggests that PEEP may slow EVLW accumulation over time and provide a protective effect that allows increased amounts of crystalloid fluids to be administered.

Incidence and timing of hypothermia in trauma patients undergoing operations.

Hypothermia is a major problem in patients who have sustained trauma. We reviewed the cases of 100 consecutive trauma patients transferred directly to the operating room (OR) from the Emergency Department (ED) in a Level I trauma center; 26 cases could not be evaluated. Forty-two patients (57%) became hypothermic at some time between injury and leaving the OR. Fifty-five patients (74%) had a temperature (T) recorded on arrival to the ED; but only 7 (12%) were hypothermic (34.7 degrees +/- 1.5 degrees C). In contrast, 34 patients (46%) arrived in the OR hypothermic (34.8 degrees +/- 0.9 degrees C) and 26 (76%) of these left the OR hypothermic (34.8 degrees +/- 0.9 degrees C). Eight additional patients (20%) arriving in the OR with a T greater than 35.9 degrees C left the OR hypothermic (35.1 degrees +/- 0.4 degrees C). The mean T loss in the ED was significantly greater than that lost in the OR (-0.8 degrees +/- 0.7 degrees C vs. 0.0 degrees +/- 0.6 degrees C; p less than 0.0001, ANOVA). Ninety-two percent of the patients lost temperature in the ED, while 43% of the patients gained temperature in the OR. Hypothermia was associated with lower Trauma Scores, and those patients who were severely hypothermic received more intravenous fluids. However, the impact of fluid infusion was not independent from Trauma Score and did not fully explain the magnitude of the heat loss. These data suggest that hypothermia in trauma patients has a multifactoral etiology related to the magnitude of injury and that the major T loss occurs in the ED rather than in the OR.(ABSTRACT TRUNCATED AT 250 WORDS)

Early postlaparotomy percutaneous endoscopic gastrostomy.

Percutaneous endoscopic gastrostomy (PEG) is a relatively new procedure, the indications for which are evolving. We have recently attempted PEG placement in 19 patients during the early postlaparotomy period (less than 14 days) for initiating enteral feedings or providing decompression of the gastrointestinal tract. All patients had unexpected postoperative complications, including neurologic catastrophe, recurrent obstruction of the small intestine, acute respiratory failure, enterocutaneous fistula or poor oral intake. Of 19 attempts, PEG placement was successful in 18 patients (94.7 per cent). There were no major complications; two minor complications (exit site infection) were associated with catheter placement. All PEG placed for enteral feedings were successfully used for nutritional support, and gastrointestinal decompression was accomplished in seven of eight patients requiring PEG. The results of this study demonstrate that PEG is technically feasible, safe and effective in the early postlaparotomy period in high-risk patients with complicated postoperative courses and the need for long term enteral access.

Crystalloid versus colloid resuscitation in experimental hemorrhagic pancreatitis.

In a canine model of acute hemorrhagic pancreatitis, crystalloid resuscitation with a balanced salt solution adequately restored plasma volume, supported tissue perfusion and prevented excessive hemodilution without detrimental effects on pulmonary pressures or oxygenation. No advantages in using colloid resuscitation were apparent in our study.

Experimental pancreatitis does not produce pulmonary hypertension.

The onset of experimental hemorrhagic pancreatitis in dogs was rapidly followed by a deterioration of CO, blood pressure, LVSW and RVSW, along with significant elevations of Hct, SVR and PVR. These alterations could all be reversed by the administration of Ringer's lactate. These findings support the concept that the major physiopathologic characteristic of severe acute pancreatitis is a loss of effective plasma and extracellular fluid volumes and that the replacement of fluid losses corrects the hemodynamic alterations. In neither of the experimental groups did pulmonary hypertension develop. We found no evidence in this model of hemorrhagic pancreatitis for a circulating pulmonary vasoactive substance.

Anaerobic liver abscess and intrahepatic metastases: a case report and review of the literature.

A patient is described in whom the first recurrence of a cloacogenic carcinoma of the rectum was an intrahepatic metastasis associated with an hepatic abscess caused by the anaerobic bacterium Peptococcus prevotii. Three previously reported cases of infection associated with hepatic tumor nodules have been found in which bacteriologic data were provided, and in all three cases anaerobic bacteria were the primary or only infection organisms. Experimental data exist which document the ability of certain anaerobic bacteria to grow selectively in tumor nodules, but not in the normal tissues of a tumor-bearing host. Since 23% of patients with liver metastases have fever and offer a clinical picture compatible with infection, occult anaerobic infection associated with liver metastases may be more common than previously recognized.

Diagnostic laparoscopy as an adjunct to selective conservative management of solid organ injuries after blunt abdominal trauma.

To investigate the efficacy of diagnostic laparoscopy (DL) as an adjunct in patient selection for conservative management of solid organ injuries (SOI) following blunt abdominal trauma, 15 patients with injuries documented by computed tomographic (CT) scanning were prospectively evaluated. Diagnostic laparoscopy was performed in an attempt to characterize SOI, to evaluate the abdomen for associated occult injuries, and to select patients for conservative management or laparotomy. The 15 patients had CT evidence of 17 SOIs (nine spleen, eight liver), and DL allowed adequate visualization of 15 of the 17 injuries. Occult hollow viscus injury was discovered in 2 of 15 patients (one colon, one small bowel) and required laparotomy. In the remaining 13 patients, DL revealed ongoing hemorrhage in four patients and poor visualization in one patient that prompted laparotomy (four splenorrhaphy, one hepatorrhaphy). Conservative management was employed in the treatment of eight patients with findings of minor injury or adequate hemostasis on DL. The average transfusion requirement in this group was 1.8 U. No patient failed conservative management. There were no complications attributable to DL. These data demonstrate that DL may become an effective adjunct in patient selection for conservative management of SOI following blunt abdominal trauma.

Comparison of live bacteria infusions in a porcine model of acute respiratory failure.

Acute respiratory failure (ARF) related to sepsis continues to have a high mortality and uncertain pathogenesis. With a reproducible live Pseudomonas aeruginosa infusion pig model, the gas exchange, hemodynamics, and pulmonary clearance of this organism were compared with live Staphylococcus aureus and Escherichia coli. Lightly anesthetized, male, mixed-breed pigs, 15-30 kg, were intubated, allowed to breathe spontaneously, and had femoral artery, central venous, and Swan-Ganz catheterization through cutdowns. After baseline data were collected, approximately 1 X 10(9) organisms/20 kg/min were infused into a central vein for 4 hr with frequent monitoring of the variables. Immediate autopsies were done for related quantitative tissue culture studies. S. aureus pigs maintained a high rate of lung bacterial clearance with pulmonary hypertension, a nonsignificant decrease in PaO2, and relatively normal lungs at autopsy. Ps. aeruginosa and E. coli animals developed systemic hypotension, pulmonary hypertension, increased pulmonary vascular resistance, hypoxemia, and decreased pulmonary clearance. Their lungs had gross congestion and edema. These studies confirm the suitability of E. coli and Ps. aeruginosa infusion into pigs as a model of sepsis-induced ARF in man. The findings also indicate that neither pulmonary hypertension nor bacterial clearance by the lungs is sufficient to cause ARF.

Prostacyclin in experimental septic acute respiratory failure.

Manipulation of prostaglandins (PG) in animal models of sepsis and acute respiratory failure (ARF) is promising. Prostacyclin (PGI2), a short-acting vasodilator, was evaluated in a porcine model of ARF produced by continuous infusion of live Pseudomonas aeruginosa (Ps.). Cardiopulmonary parameters were monitored in three groups of spontaneously breathing animals that received 0.1 micrograms PGI2/kg/min begun 20 min after baseline (Group I); 2 X 10(8) Ps./20 kg/min (Group II); identical Ps. infusion and then PGI2 begun at 20 min (Group III). The decrease in mean arterial blood pressure and cardiac index with Ps. infusion was improved by PGI2 treatment. In Groups II and III, mean pulmonary artery pressure (PAP) doubled (P less than 0.005) and pulmonary vascular resistance (PVR) tripled (P less than 0.01) by 15 min. Both PAP and PVR were decreased significantly with PGI2 treatment. In both Ps. groups, significant hypoxemia occurred. PGI2 improves cardiac output and acts as a pulmonary vasodilator, but does not improve oxygenation in this porcine model of severe ARF.

Effects of ibuprofen on a porcine model of acute respiratory failure.

Blockade of the arachidonic acid cascade has been shown to improve survival and hemodynamic alterations in animal models of sepsis and acute respiratory failure (ARF). The effects of intravenous ibuprofen, a cyclooxygenase inhibitor, were observed in 20-30 kg pigs with ARF induced by a continuous LD100 infusion of live Pseudomonas aeruginosa (2 X 10(8)/20 kg/min). Cardiopulmonary parameters were monitored in animals intubated, paralyzed, and ventilated at a 250-ml tidal volume and 0.5 FiO2. Pigs were randomly assigned to three groups: Group I received 2 bolus infusions of ibuprofen (12.5 mg/kg) at 20 and 210 min after baseline; Group II had Ps. aeruginosa (2 X 10(8) CFU/20 kg/min) only; Group III received Ps. aeruginosa and 12.5 mg/kg of ibuprofen at 20 and 210 min of ARF. Ibuprofen alone caused no significant changes in cardiorespiratory parameters. With Ps. aeruginosa infusion, significant pulmonary hypertension, hypoxemia, increased intrapulmonary shunt fraction, and systemic hypotension occurred. In the septic animals treated with ibuprofen, oxygenation was improved by a significant decrease in shunt, pulmonary edema, and pulmonary hypertension.