Abstract
Intra-abdominal hypertension (IAH) is frequently present in the critically ill and is associated with increased morbidity and mortality. Conventionally, intermittent 'spot-check' manual measurements of bladder pressure in those perceived as high risk are used as surrogates for intra-abdominal pressure (IAP). True patterns of IAH remain unknown. We explored the incidence of IAH in cardiac surgery patients and describe the intra-and postoperative course of IAP using a novel, high frequency, automated bladder pressure measurement system. Sub-analysis of a prospective, multicenter, observational study (NCT04669548) conducted in three large academic medical centers. Continuous urinary output (CUO) and IAP measurements were observed using the Accuryn Monitoring System (Potrero Medical, Hayward, CA). Data collected included demographics, hemodynamic support, and high-frequency IAP and CUO. One Hundred Thirty-Seven cardiac surgery patients were analyzed intraoperatively and followed 48 h postoperatively in the intensive care unit. Median age was 66.4 [58.3, 72.0] years, and 61% were men. Median Foley catheter dwell time was 56.0 [46.8, 77.5] hours, and median baseline IAP was 6.3 [4.0, 8.1] mmHg. 93% (128/137) of patients were in IAH grade I, 82% (113/137) in grade II, 39% (53/137) in grade III, and 5% (7/137) in grade IV for at least 12 cumulative hours. For maximum consecutive duration of IAH, 84% (115/137) of patients spent at least 12 h in grade I, 62% (85/137) in grade II, 18% (25/137) in grade III, and 2% (3/137) in grade IV IAH. During the first 48 h after cardiac surgery, IAH is common and persistent. Improved and automated monitoring of IAP will increase the detection of IAH-which normally would remain undetected using traditional intermittent monitoring methods.