A randomized crossover study of disposable thermometers for prevention of Clostridium difficile and other nosocomial infections.

OBJECTIVE

To test the hypothesis that use of disposable thermometers would result in lower rates of nosocomial Clostridium difficile diarrhea and of total nosocomial infections, compared with electronic thermometers.

DESIGN

Prospective randomized crossover trial.

SETTING

A 700-bed university hospital providing primary and tertiary care.

PATIENTS

All patients admitted to a group of 20 inpatient nursing units.

INTERVENTIONS

20 nursing units were randomized into two groups. One group randomly was assigned exclusive use of single-use disposable thermometers for patient temperature measurement, and the other group was assigned exclusive use of electronic thermometers. After 6 months, the assignments were reversed.

MAIN OUTCOME MEASURES

Rates of C difficile infections, total nosocomial diarrheal episodes, and total nosocomial infections were prospectively followed in each study unit over 11 months.

RESULTS

26,350 patients were admitted to the study units and hospitalized for 120,529 patient days. There were 947 nosocomial infections (7.86 per 1,000 patient days). Nosocomial C difficile-associated diarrhea defined by positivity to both toxin B (titer > or = 1:10) and toxin A was detected in 32 patients (3.4% of all nosocomial infections). A significantly lower rate of nosocomial C difficile-associated diarrhea was observed with disposable thermometer use (0.16 per 1,000 patient days) compared with electronic thermometer use (0.37 per 1,000 patient days, relative risk [RR] = 0.44; 95% confidence interval [CI95], 0.21-0.93, P = .026). There was no difference in overall rates of nosocomial infection between the disposable and electronic groups (8.03 and 7.68 infections per 1,000 patient days, respectively; RR, 1.04; CI95, 0.92-1.19; P = .52) or in the overall rate of nosocomial diarrhea (3.34 and 3.40 per 1,000 patient days, respectively; RR, .98; CI95, 0.81-1.19; P = .87).

CONCLUSIONS

The incidence of nosocomial C difficile diarrhea was reduced significantly by using single-use, disposable thermometers as compared with electronic thermometers, but there was no effect on either the overall rate of nosocomial diarrhea or the rate of total nosocomial infections.