Intraabdominal pressure and its relation with organ dysfunction in patients scheduled for elective cesarean section: Effect of supine vs left lateral tilt position

Abstract

Introduction Intraabdominal pressure (IAP) is related to clinical outcome of patients. It is measured as intravesical pressure through a Foley catheter in the supine position. During pregnancy, there are data showing elevated IAP and also a suggestion that it may be a false increase due to pressure on the urinary bladder by the gravid uterus in the supine position. Additionally, it is not known whether the elevated IAP during pregnancy is merely a physiological change or is associated with impairment of organ functions. We thus aimed to establish a normal value of IAP in supine (IAPsupine) as well as 10° left lateral (IAPlateral‐tilt) positions, and their association with organ functions as well as certain maternal risk characteristics. Material and methods This prospective cross‐sectional cohort study included 100 consenting parturients with term gestation posted for elective cesarean section under single‐shot subarachnoid block. IAP was measured via an indwelling Foley catheter with a transducer connected to it, as per the recommended technique. Organ dysfunction was defined as Sequential Organ Failure Assessment (SOFA) subscore ≥1 for the particular system. Trial registration: http://ctri.gov.in (CTRI/2017/11/010527). Results The IAPsupine was significantly higher than IAPlateral‐tilt (13.8 ± 2.4 vs 12 ± 2.3 mm Hg) (P < .001). The incidence of intraabdominal hypertension as per conventional definition, that is, IAP ≥12 mm Hg, was also higher in the supine position (77% vs 55%) (P < .001). None of the patients had dysfunction of the cardiovascular, renal or central nervous system. The incidence of respiratory, hepatic and hematologic dysfunction was 2%, 15% and 32%, respectively. Receiver operating characteristic analysis showed insignificant association of IAPsupine and IAPlateral‐tilt with various organ dysfunctions (P > .05). There was a significant correlation of intraabdominal hypertension when considering IAPsupine or IAPlateral‐tilt, with obesity (P = .004 and .000, respectively), as well as preeclampsia (P = .006 and .000, respectively). Conclusions In nonlaboring patients undergoing elective cesarean section, IAP is significantly higher in the supine vs 10° left lateral position. In neither position is IAP significantly associated with organ dysfunction. Thus, the usual recommendation of a supine position for measuring IAP to diagnose intraabdominal hypertension, formulated consequent to its pathological effects on organ functions, may not be applicable to pregnant patients and needs urgent validation studies.

Effect of different position on inferior vena cava dimensions and its influence on hemodynamics during cesarean section under combined spinal‐epidural anesthesia: A randomized controlled trial

“…When the IVC passes through the abdominal cavity, it is affected by intra‐abdominal pressure. Increasing intra‐abdominal pressure is significantly associated with the decreasing IVC diameter, 23 but the intra‐abdominal pressure in the supine position is significantly higher than that in the left oblique position, 24 which further explains why IVCCI is higher in supine positions. In the second place, all uterine gravity acts directly on the IVC in the supine position.…”