The Risk of Acute Kidney Injury from Fluid Restriction and Hydroxyethyl Starch in Thoracic Surgery.

BACKGROUND: Fluid is restricted in thoracic surgery to reduce acute lung injury, and hydroxyethyl starches (HES) are often administered to reduce fluid amount. This strategy may contribute to the development of acute kidney injury (AKI). We evaluated the incidence, risk factors, and prognosis of AKI in thoracic surgery. We especially focused on whether fluid restriction/HES administration increased AKI. METHODS: This is a retrospective study of patients undergoing thoracic surgery in a tertiary care academic center. Postoperative AKI was diagnosed within 72 hours after surgery based on the Acute Kidney Injury Network criteria. Demographic, intraoperative, and postoperative data were compared between non-AKI and AKI groups. Logistic regression was used to model the association between risk factors and AKI. RESULTS: Final analysis included 1442 patients. Of these, 74 patients developed AKI (5.1%). Crystalloid restriction (≤3 mL·kg·h) was unrelated to AKI, regardless of preoperative renal functions (odds ratio [OR], 0.5; 95% confidence interval [CI] 0.2-1.4). AKI occurred more often when HES were administered to the patients with decreased renal function (OR, 7.6; 95% CI, 1.5-58.1) or having >2 risk factors with normal renal function (OR, 7.2; 95% CI, 3.6-14.1). Multivariate analysis revealed several risk factors: angiotensin-converting enzyme inhibitor/angiotensin receptor blockers, open thoracotomy, pneumonectomy/esophagectomy, diabetes mellitus, cerebrovascular disease, low albumin level, and decreased renal function. CONCLUSIONS: Fluid restriction neither increased nor was a risk factor for AKI. HES should be administered with caution in high-risk patients undergoing thoracic surgery.

Effect of combined single-injection femoral nerve block and patient-controlled epidural analgesia in patients undergoing total knee replacement.

PURPOSE: Total knee replacement is one of the most painful orthopedic procedures, and effective pain relief is essential for early mobility and discharge from hospital. The aim of this study was to evaluate whether addition of single-injection femoral nerve block to epidural analgesia would provide better postoperative pain control, compared to epidural analgesia alone, after total knee replacement. MATERIALS AND METHODS: Thirty-eight patients received a single-injection femoral nerve block with 0.25% levobupivacaine (30 mL) combined with epidural analgesia (femoral nerve block group) and 40 patients received epidural analgesia alone (control group). Pain intensity and volume of patient-controlled epidural analgesia medication and rescue analgesic requirements were measured in the first 48 hours after surgery at three time periods; 0-6 hours, 6-24 hours, and 24-48 hours. Also, side effects such as nausea, vomiting, and pruritus were evaluated. RESULTS: Median visual analog scale at rest and movement was significantly lower until 48 hours in the femoral nerve block group. Patient-controlled epidural analgesia volume was significantly lower throughout the study period, however, rescue analgesia requirements were significantly lower only up to 6 hours in the femoral nerve block group. The incidences of nausea and vomiting and rescue antiemetic requirement were significantly lower in the femoral nerve block group up to 6 hours. CONCLUSION: The combination of femoral nerve block with epidural analgesia is an effective pain management regimen in patients undergoing unilateral total knee replacement.