Energy and nitrogen balance and changes in midupper-arm circumference with multiple organ failure.

Energy intake and energy expenditure, nitrogen intake, and urinary nitrogen excretion (or urea production rates) were measured in 35 intravenously fed patients with multiple organ failure over the course of their illness to determine to what extent nutrient requirements were met despite fluid retention. Energy and nitrogen balance were related to serial measurements of midupper-arm circumference (MAC). The target feeding regimen of 176 kJ (42 kcal)/kg fat-free mass (FFM) was achieved in only three patients and the target of 0.24 g N/kg FFM in only four. Two patterns of change in MAC were noted: a steady decrease with time and no change with time. Serial muscle biopsy data indicated that all the patients were wasting away; the maintenance of MAC in the group with no change over time was due to fluid retention. Abnormal losses were not measured, but energy and nitrogen balance in the group in which arm circumference decreased had no apparent effect on the rate of wasting.

The cost of an intensive care unit: a prospective study.

The cost of intensive care for patients admitted to the ICU were estimated. Patients suffering from severe combined acute respiratory and renal failure who required mechanical ventilation and renal replacement therapy (SCARRF-D) cost per day significantly more than non-renal patients (pounds 938 compared to pounds 653 per patient respectively) and their average length of stay in hospital is nearly 4 times as long (28.8 compared to 7.6 days respectively). Approximately 44% of the total cost was staff related (28% for the provision of nurses and 16% for the rest). Retrieving information related to cost was difficult, time consuming and labour intensive.

Reducing sepsis in severe combined acute renal and respiratory failure by selective decontamination of the digestive tract.

Fifteen patients with severe combined acute renal and respiratory failure (SCARRF), who required mechanical ventilation and renal replacement therapy for at least 5 days, were treated with a regimen to selectively decontaminate the digestive tract (SDD). In these patients the incidence of significant infection was compared with the infection rate in 12 similar patients with SCARRF who had not received SDD, treated over the preceding 12 months. Both groups were comparable for age, study period, sepsis score, and therapeutic intervention scoring system on admission, although the Acute Physiology and Chronic Health Evaluation score was higher (p less than .05) in the SDD-treated group. Ten (83%) of 12 control patients developed definable infections compared with five (33%) of 15 in the SDD group (p less than .05). Gram-negative bacteria and fungi were responsible for 14 of the 17 infections affecting ten control patients, compared with six of the seven infections in only four SDD patients (p less than .05). The most notable site to benefit was the respiratory tract, with only one patient in the SDD group developing a pulmonary infection compared with five in the control patients (p less than .05). Urine infections may have been reduced from six (50%) of the 12 control patients to two (13%) of the 15 SDD patients, but this difference was not significant. Although survival in the control and SDD group was comparable (42% vs. 40%), mortality overall seemed related to infection. Eleven (73%) of 15 patients with definite infection died, in contrast with five (42%) of 12 who had no infections, although this was not significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Review of available trials of selective decontamination of the digestive tract (SDD).

Eighteen studies on Selective Decontamination of the Digestive Tract (SDD) have been published up to now. A statistically significant reduction of infection rate was found in fourteen out of the fifteen controlled studies. Although all the studies were designed to evaluate infection-related morbidity as the end point, ten centres have reported fatality rates. Six centres out of the ten showed a statistically significant reduction in mortality in patients receiving SDD versus control. A recent French study describes the eradication of an outbreak of a multi-resistant Klebsiella with SDD. The Paris trial suggests a major impact of the SDD maneuver on the ICU ecology. Emergence of resistance to the SDD agents among gram-positive cocci has been described, although the clinical impact of this antibiotic side effect has not been reported so far. There are three indications for SDD, as follows: (i) trauma patients; (ii) liver transplant recipients and (iii) outbreaks of multi-resistant organisms.

Acquisition of endemic Pseudomonas aeruginosa on an intensive therapy unit.

During a 9-month period, patients, staff and environment were monitored in order to trace the source of endemic Pseudomonas aeruginosa on our intensive therapy unit (ITU). Of 81 patients studied, 14 (17%) acquired 15 different pyocin types while on the ITU. The most frequent site of colonization was the rectum (11 patients). Rectal strains subsequently appeared in urine (two patients), wound (one) and sputum (four) of six patients. Three episodes of cross-infection (wound (two), urine (one] occurred without development of rectal colonization. Strains isolated from the environment and staff were not implicated. While gastrointestinal carriage of P. aeruginosa may not be detected on admission to the ITU, excessive use of antibiotics may be responsible for apparent acquisition of the organism followed by endogenous transfer of the rectal strains to other sites of the body.

The effect of air embolization from the femoral canal on hemodynamic parameters during hip arthroplasty.

A canine laboratory and clinical study was designed to determine the effect of air embolism during hip arthroplasty. Canine femurs were pressurized with air to 250-300 mm Hg or with low-viscosity cement to 300-900 mm Hg. Pressurization with low-viscosity cement from distal to proximal with a plugged femur revealed no change in pO2, pCO2, pulmonary artery pressure, or end-tidal CO2. Air pressurization resulted in significant increases in pCO2, pulmonary artery pressure, and end-tidal CO2, and a decrease in pO2. Pressurization of the medullary canal with xenon-labeled air was used to document pulmonary embolism. In a clinical setting, two different femoral cementing techniques during total hip arthroplasty were studied to determine their effect on hemodynamic parameters associated with embolic phenomenon. Five patients had a plugged femoral canal filled from proximal to distal with a vent tube, followed by finger-packing. Three of the patients demonstrated a significant drop in pO2 and blood pressure and a rise in pCO2 and end-tidal CO2. Five other patients had their plugged femoral canals filled from distal to proximal, three with regular cement and two with low-viscosity cement, with no significant cardiopulmonary changes. The adverse cardiopulmonary effects reported during hip arthroplasty appear to be avoided by eliminating air during the cementing procedure, by filling a plugged canal from distal to proximal.

Late treatment of paracetamol poisoning with mercaptamine.

Forty patients who had taken overdoses of paracetamol were treated with mercaptamine. Twenty-three patients given mercaptamine within 10 hours of poisoning had normal liver function tests at follow-up, and one could not be traced. In 16 patients mecraptamine was begun more than 10 hours after ingestion of paracetamol ("late" mercaptamine). Eight of these patients developed severe liver damage, which in six was moderate or severe before mercaptamine administration. Acute renal failure occurred in two patients; in one other renal function was temporarily severely impaired. At follow-up two patients were not available, and one admitted moribund had died soon after admission. The remaining 13 all had normal liver function tests. It is concluded that late mercaptamine is not dangerous and may prevent further liver damage.