Future liver remnant volume is associated with postoperative fentanyl consumption following open donor hepatectomy: a retrospective multivariate analysis.

PURPOSE: Liver resection has a risk of postoperative hepatic dysfunction, including drug metabolism. Since fentanyl is primarily metabolized in the liver, liver resection requires exercising caution against fentanyl overdose in postoperative analgesia. The rationale for dose adjustment of fentanyl in the preoperative prescription for patients undergoing liver resection remains unclear. We examined whether postoperative fentanyl consumption is associated with the future liver remnant after liver resection and investigated factors influencing fentanyl consumption. METHODS: In this retrospective study, 89 living liver donors undergoing open liver resection received intravenous patient-controlled analgesia with fentanyl 2 mg with thoracic epidural analgesia. The primary outcome was postoperative hourly consumption of intravenous patient-controlled analgesia with fentanyl. Future liver remnant volume (ml) and the ratio of future liver remnant volume to whole liver volume (%) were estimated by computed tomography volumetry and compared to determine which correlated more strongly with fentanyl hourly consumption. Multivariable analysis identified independent factors affecting fentanyl consumption, with adjustments for patient characteristics and intravenous patient-controlled analgesia setting. RESULTS: Future liver remnant volume (ml) was significantly correlated more strongly than the ratio of future liver remnant (%) with postoperative fentanyl consumption (r = 0.53 vs. 0.36, p < 0.001). Larger future liver remnant volume (ß = 0.25, p = 0.006) and age < 45 years (ß = 0.24, p = 0.009) were independently associated with higher fentanyl consumption, while sex and weight were not. CONCLUSIONS: Future liver remnant volume was significantly associated with postoperative fentanyl consumption. Smaller remnant liver volume and older age (≥ 45 years) were independent factors reducing postoperative fentanyl consumption in patients undergoing open donor hepatectomy.

Gastric emptying time after breakfast in healthy adult volunteers using ultrasonography.

There is little evidence of gastric excretion after ingestion of solids. We examined gastric emptying times after ingesting normal breakfast in healthy adult volunteer using ultrasonography. Eight adult volunteers fasted for 8 h, and we examined the gastric antral area in the right lateral decubitus position using ultrasonography. Sixteen adult volunteers ingested normal breakfast. We evaluated the gastric antral area in the same manner at two consecutive time points before lunch. Gastric volume was calculated by using an approximation formula based on the antral area. Correlation coefficients between gastric volume and fasting time were calculated. The calculated gastric volume from the gastric antral area after 8 h fasting was 53.1 ml. The gastric volume correlated significantly with fasting time (r = - 0.811, P < 0.001). The time when the attenuation line obtained from two measurements between breakfast to lunch in each subject overlapped the fasting stomach volume (53.1 ml) was taken as gastric empty time. The calculated gastric emptying time was 276.4 ± 58.9 min. This result shows that gastric emptying time was lower than 5 h average after a typical breakfast that contains various food in healthy adult volunteers. However, further research is necessary to establish the clinical safety implications of these findings.

[Usefullness of Beta-blocker for Hemodynamic Changes Induced by Uterotonic Drug in a Patient with Hypertrophic Obstructive Cardiomyopathy Undergoing Elective Cesarean Section].

Combined spinal-epidural anesthesia (CSEA) was given to a 27-year-old woman with hypertrophic obstructive cardiomyopathy (HOCM) for a selective cesarean section. After the injection of uterotonic drug via uterine muscle and a vein after delivery, the patient developed dyspnea, tachycardia, ST-change on elecrocardiogram and hypotension. It is important in HOCM patients to control heart rate and left ventricular contractile force. We started to infuse beta-blocker (landiolol, 10 µg x kg(-1) x min(-1)) and improved these symptoms of the patient. This case demonstrates that CSEA is safe for HOCM patients and beta-blocker is effective to improve hemodynamic changes induced by uterotonic drug in these patients.

[Compression characteristics of graduated compression stockings used for prevention of venous thromboembolism].

BACKGROUND: Graduated compression stockings (GCS) are widely used to prevent perioperative venous thromboembolism. However, actual compression pressures of GCS on patients' legs have rarely been reported. METHODS: Four different types of GCS were evaluated. Compression pressures of GCS were measured hydrostatically by using a small balloon filled with water at the ankle, the calf and the knee (proximal end) in 463 legs of surgical patients. We also compared the influence of body mass index (BMI) on compression pressures of each GCS. RESULTS: No GCS ideally exerted compression of each sites of the legs while maintaining adequate pressure gradient from the ankle to the knee. It revealed that adequate compression of the calf and pressure gradient between the ankle and the calf could hardly be achieved simultaneously. In some GCS, BMI did not influence compression pressure but in the others compression tended to increase in patients with increased BMI. CONCLUSIONS: As the compression characteristics of GCS are different among products, selection of GCS is important for its effective use. To select a proper GCS, measurement of actual compression pressure seems necessary.