Effect of inline filtration of intravenous infusions on the incidence of thrombophlebitis.

The effect of inline filtration on the incidence of infusion phlebitis was examined in a community hospital. Two general surgical units, comparable in their patient populations, were studied during a one-month period. On one unit, an extension set with a 45 micrometer filter was attached to every i.v. catheter; no inline filtration was instituted on the second unit. The use or nonuse of a filter was not blinded. The filter was replaced every 24 hours or sooner if blockage occurred. A total of 49 patients (107 i.v.s) were studied in the group with filters and 40 patients (84 i.v.s) without filters. Phlebitis was graded on a scale of 0 to 4. The proportion of patients with phlebitis in the filter group was 86%; in the no-filter group, 75%. In the filter group, 67% of the catheterizations ended in phlebitis; in the no-filter group, 63%. Upon first catheterization, phlebitis developed in 63% of the filter group and 58% of the no-filter group. None of these differences was significant (p = 0.05). There was also no significant difference between the two groups in the severity of phlebitis and the incidence of phlebitis following the administration of irritating solutions containing cephalothin sodium or potassium chloride. Based on this study, the value of inline filtration in routine clinical conditions appears to be questionable.

Pseudobacteremia: false-positive blood cultures from mist tent contamination.

In the seven-month period from July 1975 through January 1976, 11 pediatric patients had Acinetobacter calcoaceticus var. anitratus cultured from blood; this organism had not been isolated from pediatric patients in the previous six months. In 10 of 11 patients, only the first of two cultures was positive. All patients recovered uneventfully, although only two were treated with appropriate antibiotics. Nine of 11 had been in mist tents at the time of the culture. Mist cultured from one tent contained the same organism found in the patient's blood culture. Eight of 10 patients, however, had blood for culture drawn from the same needle as samples for other blood work, compared with only three of 13 controls (p = .013); this represented a deviation from proper blood culture technique, and a mock trial confirmed contamination of blood cultures when technique was broken. Contamination by this organism occurred in the tent water reservoir and mist, and the nose and skin of the children were colonized. The hands of respiratory therapy technicians and blood-drawing personnel became contaminated while handling the mist tents. Thorough attention to hand-washing, tent sterilization, and technique in drawing blood cultures stopped the pseudo-epidemic.