Effects of positive end-expiratory pressure ventilation on splanchnic oxygenation in humans

• Published in: Journal of cardiothoracic and vascular anesthesia 1996-08, Vol.10 (5), p.598-602
• Main Authors: Berendes, Elmar, Lippert, Günther, Loick, Heinz-Michael, Brüssel, Thomas
• Format: Article
• Language: English
• Subjects: Adult; Aged; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Emergency and intensive cardiocirculatory care. Cardiogenic shock. Coronary intensive care; Female; Hemodynamics; hepatic venous oxygen saturation; Humans; Intensive care medicine; Lactic Acid - blood; Liver Circulation; Male; Medical sciences; Middle Aged; Oxygen - blood; positive end-expiratory pressure; Positive-Pressure Respiration; Prospective Studies; Splanchnic Circulation; splanchnic oxygenation; splanchnic perfusion
• ISSN: 1053-0770; 1532-8422
• DOI: 10.1016/S1053-0770(96)80136-4

To examine the influence of positive end-expiratory pressure (PEEP) ventilation on splanchnic oxygenation and lactate production in humans without pulmonary disorders. Prospective study. Single-institutional surgical intensive care unit in a university hospital. Twenty patients who underwent major abdominal surgery. Radial artery, pulmonary artery, and right hepatic vein catheters. Blood samples were collected to determine lactate concentrations and oxygen saturations. Six hours postoperatively PEEP levels (5, 10, and 15 cmH2O) were applied in a randomized order, and the following parameters were determined before and at the end of each PEEP level: cardiac output (CO); mean arterial pressure (MAP); arterial (SaO2), mixed venous (Sv¯O2) and hepatic venous oxygen saturation (ShvO2); systemic (C[a-v¯]O2) and splanchnic (C[a-hv]O2) arterial venous oxygen content difference; and arterial, mixed venous, and hepatic venous lactate concentration. CO and MAP were reduced at PEEP 10 and 15 cmH2O, accompanied by a decrease in Sv¯O2 but unchanged SaO2. A decrease in ShvO2 was seen at PEEP 15 cmH2O. C(a-v¯)O2 and C(a-hv)O2 were increased at PEEP 15 cmH2O. However, at PEEP 15 cmH2O, the percent increment in C(a-hv)O2 was greater than the increment in C(a-v¯)O2. Lactate concentrations remained unchanged. Ventilation with PEEP causes reductions in CO and MAP, resulting in a comparable impairment of systemic and splanchnic oxygen. The absence of changes in lactate concentrations indicates that a critical reduction in systemic and splanchnic oxygenation is unlikely during ventilation with low or high PEEP levels.