The Impact of an Epidural Anesthetic on the Consumption of Sevoflurane in Major Abdominal Surgery

Plain-language summary

Major abdominal surgery - like non-laparoscopic bowel resection, liver, gastric, or pancreas surgery - is performed under general anesthesia. Pain control for after the surgery can be achieved purely with intravenous and oral pain medication or in combination with freezing of the nerves. Nerve freezing (nerve block) placed before surgery has the potential to substantially reduce the amount of inhaled anesthetic given to the patient during surgery. This can benefit the patient with being more awake and crisp more quickly after surgery. It can also reduce cost to the system. A further benefit which has received very little attention so far, is that reducing the amount of inhaled anesthetic given also lowers the environmental footprint created by the anesthetic. The investigators of the proposed study plan to quantify the amount of inhaled anesthetic used for each case and will compare how the consumption is affected by whether the epidural block is applied before or after surgery. Patients will have a nerve block catheter (epidural catheter) placed prior to the induction of general anesthetic by an experienced regional anesthesiologist. The epidural catheter will be bolused with a solution to which the anesthesiologist is blinded which will either be local anesthetic or dextrose (sham). The general anesthetic will be conducted according to a the protocol with the aim of maintaining a standard anesthetic depth monitored by patient state index (PSI). Measurements of the MAC-Value (minimum alveolar concentration) of inhaled anesthetic will be recorded every five minutes and will be noted down by a blinded observer. At the end of the case the anesthesiologist blinded to the solution will inject another solution (now a dextrose (sham) or local anesthetic before the patient is woken up.

Who can participate

What they're measuring

Trial details