Prediction of post-hepatectomy liver failure by preoperative gadoxetate disodium-enhanced magnetic resonance imaging.

BACKGROUND: Approximately 15% of patients experience post-hepatectomy liver failure after major hepatectomy. Poor hepatocyte uptake of gadoxetate disodium, a magnetic resonance imaging contrast agent, may be a predictor of post-hepatectomy liver failure. METHODS: A retrospective cohort study of patients undergoing major hepatectomy (≥3 segments) with a preoperative gadoxetate disodium-enhanced magnetic resonance imaging was conducted. The liver signal intensity (standardized to the spleen) and the functional liver remnant was calculated to determine if this can predict post-hepatectomy liver failure after major hepatectomy. RESULTS: In 134 patients, low signal intensity of the remnant liver standardized by signal intensity of the spleen in post-contrast images was associated with post-hepatectomy liver failure in multiple logistic regression analysis (Odds Ratio 0.112; 95% CI 0.023-0.551). In a subgroup of 33 patients with lower quartile of functional liver remnant, area under the curve analysis demonstrated a diagnostic accuracy of functional liver remnant to predict post-hepatectomy liver failure of 0.857 with a cut-off value for functional liver remnant of 1.4985 with 80.0% sensitivity and 89.3% specificity. CONCLUSION: Functional liver remnant determined by gadoxetate disodium-enhanced magnetic resonance imaging is a predictor of post-hepatectomy liver failure which may help identify patients for resection, reducing morbidity and mortality.

Anesthesia and intraoperative high-frequency oscillatory ventilation during burn surgery.

High-frequency oscillatory ventilation (HFOV) is a mainstay in the ventilatory management of severe acute respiratory distress syndrome in our burn center. Many patients require burn surgery while on HFOV, potentially necessitating the use of HFOV during general anesthesia in the operating room. The purpose of this study was to describe the technique of providing and maintaining intraoperative HFOV. This is a retrospective analysis of the hospital and anesthesia records of all adult burn patients who went to the operating room on HFOV at our regional burn center between October 22, 1999, and April 30, 2009. There were 57 procedures performed on 36 patients who were receiving HFOV for severe acute respiratory distress syndrome available for analysis (age 45 ± 16 years, %TBSA burn 43 ± 14, % full-thickness burn 32 ± 19, and 69% with inhalation injury). Intraoperative HFOV settings were mean airway pressure 33 ± 4 cm H2O, frequency 5 ± 1 Hz, and FiO2 0.7 ± 0.2. There were no significant changes in oxygenation as measured by the PaO2/FiO2 ratio and the oxygenation index, but there was a transient but significant increase in PaCO2 intraoperatively. Existing continuous infusions of midazolam, opioids, and neuromuscular blockers were continued during surgery and were augmented by a variety of parenteral agents, including propofol, fentanyl, and ketamine during surgery. Prone positioning was required in 16 of 57 procedures. Subanalysis of the prone cases showed no significant changes in the PaO2/FiO2 ratio or oxygenation index but again showed a significant but temporary increase in intraoperative PaCO2. HFOV was aborted for conventional mechanical ventilation in three cases due to respiratory deterioration (2 cases) and hemodynamic instability (1 case). There were no intraoperative deaths. In-hospital mortality was 33%. Intraoperative HFOV was feasible and safe in the overwhelming majority of cases, and aside from an inconsequential period of intraoperative hypercapnia, this was not associated with any hemodynamic instability or compromise in oxygenation.