Anesthesia for day-case arthroscopic knee surgery in adult patients.

Background of the study: Day-case surgery has a high patients turnover. Different anesthetic techniques could be an obstruction for this high patients turnover, because they could take a lot of time. In this study, we are looking for the anesthetic technique which garantees the high patients turnover, and for this reason is time efficient. The anesthestic technique also has to deal with patients satisfaction and take care for good perioperative and surgical conditions. In this study, we want to find the anesthetic technique with the best patients satisfaction, best surgical and anesthesiological conditions and the technique with the highest time efficiency. We compare three anesthetic techniques. This study is a prospective, randomised and blinded trial. Patients get randomised to one of three anesthetic techniques; spinal anesthesia, general anesthesia or a sciatic-femoral nerve block. We will measure different characteristics before, during and after the procedure; like time, surgical conditions and satisfaction, patients satisfaction and anesthetic conditions. The study population will consist of healthy, adult patients in the age of 18-75 years, in ASA-class I-II, who get operated for arthroscopic knee surgery. Primary study outcome is time to home discharge of the patient. Secundary study outcomes are preparation times of the anesthetic technique, during times of operation and recovery. Patients, surgeons and anesthesists satisfaction also will be measured. Conditions of anesthetic techniques will be measured with accurate tests.

To find the anesthetic technique with the highest success rate in adult patients for ambulatory arthroscopic knee surgery in day-case setting, we studied whether a sciatic-femoral nerve block is a better technique than general or spinal anesthesia.

We measure the preparation time of the anesthetic technique from skin disinfection or start with preoxygenation (t=1) until the moment the patient is back in supine position or the end of induction when the LMA is in situ (t=2). Duration of the surgery is measured from skin disinfection (t=3) until bandaging (t=4). Recovery times are measured from arrival at the PACU (t=5) until discharge from the hospital (t=6). The total time the patient spends at the operation complex is measured from arrival at the holding area (t=0) until home discharge (t=6).

The patients will get randomized to receive one of the three anesthetic techniques by computer randomization:

1. Spinal anesthesia;

2. A sciatic-femoral nerve block;

3. General anesthesia.