Patients who receive remifentanil as an adjuvant to general anaesthetic for spinal surgery have significantly less intraoperative blood loss compared with those who receive fentanyl as adjuvant to general anaesthesia, a study in BMC Anesthesiology has found.
Hiroaki Kawano (Department of Anesthesiology and Clinical Research, National Hospital Organization Zentusji Hospital, Zentsuji, Japan) report that remifentanil is an ultra-short-acting phenylpiperidine opioid that is widely used for general anaesthesia because of its pharmacokinetic profile, adding there is a suggestion that the drug could reduce intraoperative blood loss.
Therefore, they performed a retrospective review of patients who underwent spinal surgery at their hospital between April 2010 and March 2011 to review the estimated blood loss (the primary endpoint) with remifentanil vs. that with fentanyl (as adjuvants to general anaesthesia). Estimated blood loss was calculated by factoring in the surgical suction volume and the weight of the gauze from the operative field.
Of the 64 patients (who either underwent laminoplasty or laminectomy) in the study, 35 received remifentanil and 29 received fentanyl. The authors report: “Intraoperative blood loss was significantly lower in the remifentanil group than in the fentanyl group (125±67ml vs. 165±82ml, respectively; p=0.035).” They add that intraoperative systolic blood pressure, mean blood pressure, and diastolic blood pressure were all significantly lower with remifentanil, which they say suggests that: “remifentanil may decrease intraoperative blood loss by inducing a sustained drop in blood pressure during the intraoperative period.”
According to Kawano et al, the study is the first study to show that the choice of adjuvant opioid analgaesic significantly influences intraoperative blood loss during spinal surgery. They conclude: “This study demonstrates that intraoperative blood loss during spinal surgery can be decreased by using remifentanil rather than fentanyl as the opioid adjuvant during general anaesthesia. Given the importance of decreasing intraoperative bleeding on clinical outcomes, the effect of remifentanil on blood loss warrants a large-scale prospective randomised controlled trial.”