Intraabdominal and Thoracic Pressures in Critically Ill Patients with Suspected Intraabdominal Hypertension

Abstract

ObjectiveTo study the correlation between intraabdominal and intrathoracic pressures in patients with suspected intraabdominal hypertension. DesignA prospective, observational cohort study. SettingPolyvalent intensive care unit of a University hospital. PatientsTwenty-seven medical-surgical patients dependent upon controlled mechanical ventilation due to acute respiratory failure and with several risk factors for intraabdominal hypertension (IAH). Main variablesIntraabdominal (IAP), esophageal (Peso) and airways pressures were measured under static (st) and dynamic (dyn) conditions. Respiratory system (Crs), lung (Clu) and chest wall compliance (Ccw) were calculated. ResultsIn 10 patients IAP>12mmHg (IAH, IAPst, 14±2 [12–21] mmHg), while in the rest the pressure proved normal (n=17; IAPst, 8±2 [3–11] mmHg). Pesost was 11±5 (2–27) and Pesodyn 7±4 (2–24) cmH2O. Depending on the presence or absence of IAH, Pesost was 9±4 vs 7±3cmH2O (P=.2) and Pesodyn 6±2 vs 4±3cmH2O (P=.3), respectively. The correlation between Pesost and dyn with IAPst was 0.5 (P=.003) and 0.4 (P=.03), respectively. The compliance components were decreased (Crs, 31±8; Clu, 52±22 and Ccw, 105±50ml/cmH2O); Ccw was significantly lower in patients with IAH (81±31 vs 118±55ml/cmH2O; P=.02). The correlation coefficient between IAPst and Ccw was −0.7 (P<.001), and −0.5 (P=.002) with respect to Crs. ConclusionsA stiffer chest wall was observed in patients with IAH. In patients with risk factors for IAH, pressures in these compartments were highly variable.