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Notes: A fluid logic ventilator with significant advantages over other compact portable ventilators is described. The variable Flo2, airway pressure gauge and versatility of the ventilator make it suited to mobile intensive care units and use during total intravenous anaesthesia.

Notes: We retrospectively compared the changes in serum albumin concentration and colloid osmotic pressure between survivors and nonsurvivors of prolonged (≥7 days) critical illness over a 2-year period from 1 July 1995. All patients had serum albumin measured daily, and colloid osmotic pressure measured 5 days a week, throughout their ICU admission. They received crystalloid and colloid infusions as well as parenteral or enteral feeding. Infusions of albumin were not used to treat hypoalbuminaemia. One hundred and forty-five patients were included, 66 nonsurvivors and 79 survivors. Nonsurvivors were significantly older than survivors [mean (95% CI): 58 (3.8) and 49 (4.1) years, respectively] and had a greater risk of death [mean (95% CI): 0.44 (0.06) and 0.28 (0.05); p 〈 0.05]. There was no significant difference in gender, APACHE II score [mean (95% CI): 22 (2.7) (nonsurvivors); 18 (2.3) (survivors)] or length of stay [median (interquartile range): 14 (9–27) days (nonsurvivors); 15 (9–26) days (survivors)]. There was no difference between the two groups in the absolute minimum serum albumin concentrations reached, the time to reach that minimum or the minimum in the first 7 days. However, nonsurvivors had a significantly lower mean serum albumin concentration: [mean (95% CI): 15.7 (5.1) gl−1 compared with 18.3 (4.6) gl−1 in survivors; p 〈 0.05]. They also had a lower recovery mean (the weighted mean after the minimum value): [mean (95% CI): 13.3 (5.1) gl−1 (nonsurvivors) and 18.6 (5.3) gl−1 (survivors); p 〈 0.01]. Analysis of colloid osmotic pressure results showed no difference between the groups in mean, minimum or recovery mean. Regression analysis of mean colloid osmotic pressure and albumin revealed that albumin only contributed 17% of the colloid osmotic pressure in these patients. The similar decrease in albumin in nonsurvivors and survivors may reflect the acute inflammatory response and/or haemodilution. However, survivors showed an ability to increase serum albumin concentrations, possibly owing to resumption of synthesis. The colloid osmotic pressure varied little between or within either group of patients, possibly because of the use of artificial colloids. There was no relationship between death and colloid osmotic pressure.

Notes: Liver samples were obtained at hepatectomy from patients with end stage alcoholic liver disease (n = 5), primary biliary cirrhosis (n = 5) and chronic rejection needing retransplantation (n = 5). Normal liver material was also obtained from five organ donors. From these samples microsomes were made containing cytochrome P450 3A. The amount of this enzyme was measured by Western immunoblotting and its function assessed by measuring the rate of production of two metabolites of midazolam, 1-hydroxy midazolam and 4-hydroxy midazolam. There was a wide range in all groups for both the expression and function of this enzyme. Liver tissue affected by cirrhotic disease showed greater preservation of enzyme function than that affected by hepatocellulur disease. There was a good correlation between the expression of the enzyme and production of the 1-hydroxy metabolite, but a poor correlation between production of the 4-hydroxy metabolite and expression. This poor correlation may reflect the failure to measure the specific enzyme responsible for producing 4-hydroxy midazolam.

Notes: The aim of this in-vitro study was to investigate the incidence of propofol agglutination with serum from critically ill patients. Serum (400 μl) from 58 critically ill patients and 30 healthy volunteers was incubated with 10 μl of either propofol, Intralipid 10% or Intralipid 20%. Control incubations contained serum only. At 24 h, the serum was examined macroscopically and microscopically for agglutination. Agglutination was seen with Intralipid 20% in serum from all critically ill patients and 13.3% of volunteers. Serum from 91.4% of critically ill patients was agglutinated with Intralipid 10% and only 3.3% of the healthy volunteers. In comparison, propofol produced agglutination in 74.1% of critically ill patients and in none of the serum from healthy volunteers (p 〈 0.05 propofol versus Intralipid 10%, p 〈 0.0001 propofol versus Intralipid 20%). No correlation was seen between agglutination and age, sex, APACHE II score or plasma concentration of acute phase proteins. However, agglutination of propofol and Intralipid 10% was more frequent (p 〈 0.001) in serum from patients with pulmonary disease, than in patients with normal lungs. The clinical implications of these in-vitro findings are unclear and need further investigation.

Notes: We have compared glomerular filtration rate measured by creatinine clearance with that measured by 51Cr-EDTA clearance after liver transplantation. Fourteen pairs of values were obtained from seven patients on the first and second days after operation. There were wide discrepancies between the values for glomerular filtration rate measured by the two methods, with a regression co-efficient of 0.43 (p = 0.12). Both methods assume a steady state, with no change of extracellular fluid volume or in the rates of exchange between physiological compartments, that does not apply in the immediate period after operation. The results show the difficulties of using clearance techniques to assess renal function after major surgery. Since drug therapy may be based on these measurements, we suggest that in this group of patients isolated clearance values should not be used.

Notes: The efficacy of low-dose dopamine as a renal protective agent was compared with that of dopexamine in patients who underwent orthotopic liver transplantation. Twelve patients who received a continuous infusion of dopexamine (1–3 μg/kg/minute) were matched for age, diagnosis, pre-operative creatinine clearance and blood loss with 12 patients who received a low-dose infusion of dopamine (2 μg/kg/minute). The catecholamine infusion was started after induction of anaesthesia and continued for 48 hours after surgery. Patients in the dopexamine group had less evidence of renal impairment and failure than those in the dopamine group during 7 days after the operation, although the differences between groups did not achieve statistical significance. Similarly there were no significant differences between the two groups in peri-operative urine output, urine/plasma osmolality ratio or creatinine clearance. Dopexamine is at least as effective as dopamine for renal protection in patients who undergo liver transplantation.

Notes: The postoperative course of 335 adult patients who underwent orthotopic liver transplantation from 1968–1987 was reviewed retrospectively to identify patients who died in the intensive care unit and the causes of death. Forty-four percent of all deaths occurred in the intensive care unit. The mortality rate in the intensive care unit peaked in 1984 (48%), but decreased to 11% in 1987. The main causes for death in the intensive care unit were infection (55%) and haemorrhage (19%). The patients who died spent more time in the intensive care unit, had a longer period of tracheal intubation and received a larger intra-operative blood transfusion than patients who died in other locations.