The Science Journal of the American Association for Respiratory Care
Background: An earlier randomized controlled trial showed the changing from daily to weekly (or as-needed) changes of in-line suction catheters was associated with substantial cost savings without a higher rate of ventilator-associated pneumonia (VAP). To examine the impact of decreasing the frequency of changing in-line suction catheters in our MICU, we conducted an observational study comparing the catheter costs and frequency of VAP during two periods: 1. The control period, during which in-line suction catheters were changed daily, vs. 2. The treatment, during which the catheters were changed every 7 days or sooner for mechanical failure or soilage.
Methods: All adult patients admitted to our eighteen-bed MICU were evaluated for 30 days proceeding the practice change (May 1999) and for 30 days thereafter. To avoid bias related variation in VAP frequency, we also examined the rates of VAP for the same 30-day period one-year earlier (May 1998). The occurrence of VAP was judged by an infection control nurse who standardly applied institutional criteria based on CDC guidelines. Rates of VAP were calculated as the mean/100 ventilator -days for each 30-day interval. Use of ventilators (Malinckrodt-Nellcor-Puritan-Bennett 7200 AE), humidifiers (Fisher & Paykel) and disposable non-heated wire circuits were uniform over the study. As were policies regarding humidity and temperature setting. Result: As a measure of the stability of VAP rates in the MICU, the frequency of VAP for the 30-day interval one year before the study was similar to the rate during the control period. During this control period, 36 patients accounted for 319 ventilator-days and no cases of VAP were observed. For the 30-day period after implementing the weekly catheter change policy, 42 patients accounted for 348 ventilator days and, as during the control period, no cases of VAP were observed. The mean (± SD) duration of in-line suction catheters used during the treatment period was 3.1 days ± 2.27 days and 43% of patients had the same catheter in place for > 3 days (range 4-9 days). The actual cost of catheters used during the treatment period was lower than during the control period ($355 vs. $2,201), predicted an annualized savings on catheter costs of $22,152.
Conclusions: We conclude: (1) a policy of weekly vs. daily changes of in-line suction catheters was associated with substantial cost savings without any appreciable increase in the frequency of ventilator-associated pneumonia. (2) to the extent that these findings confirm the results of prior studies, they endorse a policy of changing in-line suction catheters weekly rather than daily.