Propofol Target-Controlled Infusion Versus Dexmedetomidine for Sedation During Chronic Subdural Hematoma Surgery Under Local Anesthesia

Chronic subdural hematoma is a collection of old blood on the surface of the brain that mainly affects older adults. It is often treated by draining the blood through a small hole in the skull (burr hole), under local anesthesia combined with intravenous sedation while the patient keeps breathing spontaneously. Propofol and dexmedetomidine are the two sedatives most commonly used for this purpose. This randomized pilot study will compare how well each drug maintains a moderate and stable level of sedation during surgery. Sixty adults will be randomly assigned to receive either propofol by target-controlled infusion or dexmedetomidine. The main outcome is the percentage of surgical time spent at the target sedation level, defined as a Richmond Agitation-Sedation Scale (RASS) score between -2 and -3. The study will also compare the time needed to reach the target sedation, breathing and cardiovascular side effects, sedation failures, recovery time, and surgeon and anesthesiologist satisfaction. The results will be used to estimate the sample size of a future confirmatory trial.

Inclusion Criteria: * Age 18 years or older * Confirmed diagnosis of unilateral chronic subdural hematoma scheduled for burr-hole surgery under local anesthesia with sedation * Glasgow Coma Scale score ≥ 13 * Baseline Richmond Agitation-Sedation Scale score of 0 or -1 before any sedation * ASA physical status I to III * Written informed consent signed by the patient Exclusion Criteria: * Refusal to participate * Allergy or contraindication to propofol or dexmedetomidine * Major cognitive impairment preventing understanding of instructions * Receptive aphasia preventing RASS assessment * Baseline heart rate \< 50 beats per minute * Second- or third-degree atrioventricular block without a pacemaker * ASA III with decompensated respiratory disease (COPD on long-term oxygen therapy, severe asthma) * Body mass index \> 35 kg/m² * Inability to understand the language without an available interpreter * Participation in another clinical trial