Postoperative intra-abdominal pressure and renal function after liver transplantation.

HYPOTHESIS: Intra-abdominal hypertension frequently threatens renal function early after orthotopic liver transplantation (OLT). DESIGN: A prospective study of consecutive patients who underwent OLT. SETTING: The intensive care unit of a National Health Service teaching hospital. PATIENTS AND MAIN OUTCOME MEASURES: The intra-abdominal pressure (IAP) of 108 consecutive patients who underwent OLT was postoperatively measured 3 times a day for 72 hours using the urinary bladder technique. Intra-abdominal hypertension was defined as an IAP of 25 mm Hg or higher. RESULTS: Thirty-four patients (31%) had a high IAP. Acute renal failure developed in 17 recipients (16%), 11 (65%) of whom had intra-abdominal hypertension (P<.01), with a mean +/- SD IAP of 27.9 +/- 9.9 mm Hg vs 18.6 +/- 5.2 mm Hg in those without acute renal failure (P<.001). The subjects with a high IAP were more frequently administered loop diuretics to maintain adequate diuresis (P<.001) and had a low mean arterial pressure on the day of surgery (P<.01), despite the fact that they were given more intravenous fluids (P<.01) and did not differ in the need for inotropic drugs. Logistic regression analysis showed that intraoperative transfusions of more than 15 U, respiratory failure, and intra-abdominal hypertension (P<.01) were independent risk factors for renal failure. The length of intensive care unit stay was similar in the patients with a normal and a high IAP, but mortality was higher among the latter (P =.02). CONCLUSIONS: Intra-abdominal hypertension is common after OLT and is significantly associated with renal failure, reduced urinary output, and intensive care unit mortality. It is, therefore, worth monitoring IAP in those undergoing OLT.

Intra-abdominal pressure monitoring in liver transplant recipients: a prospective study.

OBJECTIVE: No data are available on the incidence and clinical relevance of increased intra-abdominal pressure after orthotopic liver transplantation. This study assessed abdominal hypertension in a population of transplanted patients as this may be an important cofactor in early postoperative complications. DESIGN AND SETTING: Prospective clinical study in an intensive care unit of a national health system teaching hospital PATIENTS AND MEASUREMENTS: Abdominal pressure was measured every 6 h using the urinary bladder method and was considered elevated when it was 25 mmHg or higher. Hemodynamic status was evaluated at the same times. Renal function was assessed on the basis of hourly urinary output by calculating serum creatinine on postoperative days 2 and 4 and the filtration gradient; patient outcomes were also considered. RESULTS: Intra-abdominal hypertension was observed in 32% of cases; the subjects with high abdominal pressure had significantly lower mean artery pressure values but did not differ in terms of central venous pressure or cardiac output. High intra-abdominal pressure was more frequently associated with renal failure, a lower filtration gradient, delayed postsurgical weaning from ventilation, and a worse outcome. CONCLUSIONS: Abdominal hypertension is frequent after liver transplantation and may be associated with a complicated post-operative course.

Renal failure and abdominal hypertension after liver transplantation: determination of critical intra-abdominal pressure.

There is growing interest in measuring intra-abdominal pressure (IAP) in postsurgical and critically ill patients because increased pressure can impair various organs and functions. The aim of this study was to evaluate the effect of different IAP levels on the postoperative renal function of subjects undergoing orthotopic liver transplantation. IAP was measured every 8 hours with the urinary bladder pressure method for at least 72 hours after surgery. At the end of the study, the patients were classified on the basis of their IAP values: < or = 18 mm Hg (group A), 19 to 24 mm Hg (group B), > or = 25 mm Hg (group C). The three groups were compared in terms of the incidence of acute renal failure (defined as blood creatinine > 1.5 mg/dL or an increase in the same of > 1.1 mg/dL within 72 hours of surgery), hourly diuresis, blood creatinine, the filtration gradient, hemodynamic variations, and outcome. The incidence of renal failure was higher among the subjects in group C (P < .05 versus group A and < .01 versus group B), who also had higher creatinine levels (P < .01), a greater need for diuretics (P < .01) and a worse outcome (P < .05). Receiver Operator Characteristic curve analysis showed that an abdominal pressure of 25 mm Hg had the best sensitivity/specificity ratio for renal failure. An intra-abdominal pressure of > or = 25 mm Hg is an important risk factor for renal failure in subjects undergoing liver transplant.