[Antibiotic prophylaxis in intensive care patients].

132 intensive care patients who did not show symptoms of bacterial infection upon admission were subdivided at random into two groups. 69 patients (37 males, 32 females) were given antibiotic prophylaxis with penicillins or cephalosporins and the remaining 63 patients (37 males, 26 females) did not receive any antibiotic prophylaxis. The average age and the median duration of treatment in the intensive care unit was the same for both groups. 1. Antibiotic prophylaxis neither reduced the infection rate nor the mortality. 2. Pleuropulmonary infections were not influenced in respect to incidence, mortality or time of occurrence by antibiotic prophylaxis. 3. The percentage of patients with gram-negative tracheal flora increased significantly from the third day of antibiotic prophylaxis onwards in comparison with those patients without antibiotic prophylaxis. 4. The incidence of, and mortality attributable to septicaemia was not influenced by antibiotic prophylaxis, but septicaemia in patients receiving antibiotic prophylaxis was significantly delayed. From the seventh day on, septicaemia was found more frequently in patients given antibiotic prophylaxis than in patients receiving none. 5. Patients receiving antibiotic prophylaxis acquired significantly fewer urinary tract infections. However, from the fifth day on, there was no difference between the two groups in regard to the rate of incidence of significant bacteriuria. 6. Morbidity and mortality from peritonitis was not influenced by antibiotic prophylaxis. 7. The organisms causing infections in patients who received antibiotic prophylaxis mostly belonged to the enterobacteriaceae, pseudomonas and candida species which were resistant to the antibiotics given prophylactically. The organisms causing infection in the group not receiving antibiotic prophylaxis were coagulase-positive staphylococci in about 50% of the cases, followed by the enterobacteriaceae and pseudomonas species; the resistance patterns towards the tested antibiotics were characteristic of these groups of organisms. 8. Fever proved to be a reliable parameter in establishing the presence or absence of infection. The mean rectal temperature showed a significant difference in medical patients from the second day, in surgical patients from the third day and im polytraumatized patients from the fourth day on, whereas the mean leucocyte counts did not differ significantly in patients with or without infection. 9. Environmental bacteriological studies in the vicinity of the group of patients given antibiotic prophylaxis showed significantly more gram-negative bacteria than in the group without. However, when the groups were subdivided into intubated and non-intubated patients, a significant rise in environmental gram-negative bacteria was found only in intubated patients receiving antibiotic prophylaxis, whereas no such influence of antibiotic prophylaxis was apparent in the non-intubated patients...