Interaction Between Intra-Abdominal Pressure and Positive-End Expiratory Pressure

Abstract

OBJECTIVE: The aim of this study was to quantify the interaction between increased intra-abdominal pressure and Positive-End Expiratory Pressure. METHODS: In 30 mechanically ventilated ICU patients with a fixed tidal volume, respiratory system plateau and abdominal pressure were measured at a Positive-End Expiratory Pressure level of zero and 10 cm H 2 O. The measurements were repeated after placing a 5 kg weight on the patients’ belly. RESULTS: After the addition of 5 kg to the patients’ belly at zero Positive-End Expiratory Pressure, both intra-abdominal pressure (p<0.001) and plateau pressures (p=0.005) increased significantly. Increasing the Positive-End Expiratory Pressure levels from zero to 10 cm H 2 O without weight on the belly did not result in any increase in intrazxabdominal pressure (p=0.165). However, plateau pressures increased significantly (p< 0.001). Increasing Positive-End Expiratory Pressure from zero to 10 cm H 2 O and adding 5 kg to the belly increased intra-abdominal pressure from 8.7 to 16.8 (p<0.001) and plateau pressure from 18.26 to 27.2 (p<0.001). Maintaining Positive-End Expiratory Pressure at 10 cmH 2 O and placing 5 kg on the belly increased intra-abdominal pressure from 12.3 +/− 1.7 to 16.8 +/− 1.7 ( p<0.001 ) but did not increase plateau pressure (26.6+/−1.2 to 27.2 +/−1.1 − p=0.83 ). CONCLUSIONS: The addition of a 5kg weight onto the abdomen significantly increased both IAP and the airway plateau pressure, confirming that intra-abdominal hypertension elevates the plateau pressure. However, plateau pressure alone cannot be considered a good indicator for the detection of elevated intra-abdominal pressure in patients under mechanical ventilation using PEEP. In these patients, the intra-abdominal pressure must also be measured.

Differential Effects of Intraoperative Positive End-expiratory Pressure (PEEP) on Respiratory Outcome in Major Abdominal Surgery Versus Craniotomy

“…As PEEP might influence the plateau pressure, 26 we excluded plateau pressure as a covariate from our primary logistic regression model to eliminate collinearity. We found that the association between application of high PEEP and a decreased risk of post-operative respiratory complications remained significant (Table 3).…”

The Impact of Various Anthropometric Measurements of Obesity on Pulmonary Function in Candidates for Surgery

“…The lung, thoracic cage, and the abdominal cavity comprise a closed system with the diaphragm as the connecting interface. When there is an increase in the abdominal and diaphragmatic pressure, the pleural pressure may be altered and a decrease in total lung capacity, pulmonary compliance, and pulmonary volume may follow [33]. Frezza et al demonstrated that increases in BMI are associated with increases in intra-abdominal pressure [34].…”

Effect of multimodality chest physiotherapy on the rate of recovery and prevention of complications in patients with mechanical ventilation: A prospective study in medical and surgical intensive care units

“…PEEP levels >10 cm H 2 O may increase the risk of mortality and morbidity in critically ill patients with a significant increase in the intra-abdominal pressure. [33] High levels of PEEP may be necessary to maintain or restore oxygenation, despite the fact that "aggressive" mechanical ventilation can markedly affect cardiac function in a complex and often unpredictable fashion. [34] As the heart rate usually doesn't change with PEEP, the entire fall in the cardiac output is a consequence of a reduction in left ventricular stroke volume.…”