Intra-abdominal pressure measurement using the FoleyManometer does not increase the risk for urinary tract infection in critically ill patients

Objective: The aim of this study was to determine whether intra-abdominal pressure (IAP) monitoring using the FoleyManometer (Holtech Medical, Charlottenlund, Denmark) increases the risk of urinary tract infection (UTI). Design: A retrospective database review was conducted. Setting: The study was conducted in the 12-bed medical intensive care unit of ZNA Stuivenberg Hospital (Antwerp, Belgium), a tertiary hospital. Patients: There were 5,890 patients admitted to the medical intensive care unit of which 1,097 patients underwent intrabladder pressure (IBP) monitoring as estimate for IAP. Interventions: Crude and adjusted UTI rates were compared among patients undergoing IAP measurements with three different intrabladder methods: a modified homemade technique, a FoleyManometer with 35 ml reservoir, and a FoleyManometer low volume (FoleyManometerLV) with less than 10 ml priming volume. Measurements and results: Four consecutive time periods of 24 months were defined and compared with regard to IAP measurement: period 1 (2000-2001), during which IAP monitoring was not used routinely (which serves as a control group), was compared with period 2 (2002-2003), using a modified homemade technique; period 3 (2004-2005), introducing the FoleyManometer; and finally period 4 (2006-2007), in which the FoleyManometerLV was introduced. The incidence of IBP measurements increased from 1.4% in period 1 to 45.4% in period 4 (p < 0.001). At the same time, the Simplified Acute Physiology Score (version 2) (SAPS-II) increased significantly from 24.4 +/- 21.5 to 34.9 +/- 18.7 (p < 0.001) together with the percentage of ventilated patients from 18.6% to 40.7% (p < 0.001). In total, 1,097 patients had IAP measurements via the bladder. The UTI rates were adjusted for disease severity by multiplying each crude rate with the ratio of control versus study patient SAPS-II probability of mortality. Crude and adjusted UTI rates per 1,000 catheter days (CD) were on average 16.1 and 12.8/1,000 CD, respectively, and were not significantly different between the four time periods. Conclusions: Intrabladder pressure monitoring as estimate for IAP either via a closed transducer technique or the closed FoleyManometer technique seems safe and does not alter the risk of UTI in critically ill patients.