[Abstract] 251: ECMO’s ASSOCIATION WITH INTRA-ABDOMINAL HYPERTENSION AND ABDOMINAL COMPARTMENT SYNDROME

Learning Objectives: Elevation in intra-abdominal pressure (IAP) resulting in intra-abdominal hypertension (IAH) or abdominal compartment syndrome (ACS) is associated with mortality rates of up to 60% in children and is an independent predictor of mortality. These patients often receive aggressive fluid resuscitation following ECMO initiation. This fluid resuscitation coupled with bowel ischemia reperfusion injury causing increased capillary permeability and extravasation of fluid into mesentery is thought to contribute to increased IAPs. IAH is defined as sustained or repeated pathological elevation of IAP >10 mmHg by WSACS, which we defined as 8 hours. ACS in children is defined as a sustained elevation in IAP >10 mmHg associated with new or worsening organ dysfunction, however for our study we defined it as IAP >20 for 8 consecutive hours because of the difficulty to distinguish whether the organ dysfunction seen was due to ACS or the initial event that led to need for ECMO. Our research aims to determine the incidence of IAH in patience on ECMO and if there is an association between IAH on ECMO and AKI. Methods: Our current results represent the pilot phase that currently includes 31 patients (37 weeks gestation – 18 years) on ECMO. Premature babies and patients with chronic kidney disease, an open abdomen or conversion from cardiopulmonary bypass to ECMO were excluded. Demographic data, relevant physiologic parameters, laboratory data and parameters determining causes of AKI were collected prospectively. IAP were monitored via indwelling urinary catheter every 4 hours. Blood samples were collected daily except in patients that became anuric. The aforementioned parameters were monitored prior to initiating ECMO and during ECMO for 7 days. Results: Out of the 31 patients, 26/31 (84%) developed IAH. Only 2/31 met criteria for abdominal compartment syndrome. Of the 26 patients that developed IAH, 43% developed AKI using pRIFLE and kDIGO. Of the 5 patients that did not develop IAH, 60% (kDIGO) and 40% (pRIFLE) developed AKI. Statistical tests were unable to be performed based on only 5 patients on ECMO not developing IAH. Conclusions: ECMO was associated with a high incidence of IAH. Nearly half of the patients with IAH also had AKI. This is the first step in determining the effects of IAH on morbidity and mortality in patients on ECMO. Our results at this stage cannot determine if there is an association but further analysis will be carried out as more patients are enrolled