Prediction of Hidden Blood Loss During Posterior Spinal Surgery.

Objective Identification of the risk factors for extraordinary hidden blood loss (HBL) could clarify the underlying causes and provide more appropriate management. This study aims to identify the predictors of HBL in spinal surgery.Methods Medical records were retrospectively retrieved to collect the data of patients who undergoing posterior thoracic and lumbar fusion surgery or scoliosis surgery. Demographic information, perioperative visible blood loss volume, as well as laboratory results were recorded. The patients receiving fusion surgery or scoliosis surgery were further divided into the HBL positive subgroup and the HBL negative subgroup. Differences in the variables between the groups were then analyzed. Binary logistic regression analysis was performed to determine independent risk factors associated with HBL.Results For patients undergoing posterior spinal surgery, the independent risk factors associated with HBL were autologous transfusion (for fusion surgery P=0.011, OR: 2.627, 95%CI: 1.574-2.782; for scoliosis surgery P<0.001, OR: 2.268, 95%CI: 2.143-2.504) and allogeneic transfusion (for fusion surgeryP<0.001, OR: 6.487, 95%CI: 2.349-17.915; for scoliosis surgery P<0.001, OR: 3.636, 95%CI: 2.389-5.231).Conclusions Intraoperative blood transfusion might be an early-warning indicator for perioperative HBL.

Influence of Sex on Remifentanil's Cough-prevention Effect during Anesthetic Emergence.

OBJECTIVE: To investigate the influence of sex on the cough-preventing effect of target-controlled infusion(TCI)of remifentanil during anesthetic emergence. METHODS: A total of 25 female(group F)and 25 male(group M)patients undergoing thyroidectomy were recruited in the current study. Anesthesia was maintained with sevoflurane and remifentanil TCI.At the end of the surgery,inhalational anesthetics were discontinued,and remifentanil TCI at an effect-site concentration(Ce)of 2.0 ng/ml was maintained during emergence until extubation. The cough score,blood pressure,and heart rate(HR)during peri-extubation period as well as the respiratory rate,calm score,and sore throat score after extubation were evaluated. RESULTS: During extubation,the proportion of patients with no cough or just a single cough was significantly higher in group F than in group M(88% vs. 64%,P=0.047). Mean arterial pressure(P=0.025,P=0.037)and HR(P=0.035)were significantly increased during extubation compared with preoperative levels in group M. CONCLUSIONS: Sex may influence the cough-preventing effect of remifentanil TCI during anesthetic emergence. At a Ce of 2.0 ng/ml,remifentanil has better cough-preventing effect and more stable hemodynamic status in females than in males.