Regional Anesthesia (Supra-Orbital and Infra-Orbital Nerve Block) (SION) for Pain Management in Trans-sphenoidal Hypophysectomy

Combined regional and general anesthesia for surgery is known to provide superior pain control in the peri-operative period (intra and post-operative). Of particular interest in neurosurgery are more rapid patient awakening and earlier ability to perform adequate post-operative neurological exam. In addition to this, regional anesthesia can decrease the total amount of systemic pain medications necessary and thus decrease their associated side effects. Consequently, less systemic pain medications can benefit the patient in many ways.

By modifying the postop pain regime to include intraoperative regional anesthesia, there could be increased patient satisfaction, and significant economic gains to the hospital through a more streamlined, shorter, more pleasant hospital course for the patient. Patients who have this trans-sphenoidal pituitary surgery are usually same day admission patients who, following their surgery, are admitted for up to 24 hours postoperatively. Usually prolonged admissions result from headache and nausea +/- vomiting. Etiology of the headache is likely multifactorial. One theory is that stimulation of the peripheral trigeminal (Cranial Nerve Number V) fibers in the V1 and V2 distribution of the face by the surgical endoscope and surgical trauma may lead to release of inflammatory mediators and post-operative migraine. It has been shown that repetitive injection of local anesthetics in the distribution of supra-orbital nerve V1 and infra-orbital nerve V2 can decrease the incidence of chronic idiopathic migraine headaches not related to surgery. By administering regional anesthesia to the patient intra-operatively during their general anesthetic for the surgery, pain scores may be reduced, PONV (postoperative nausea and vomiting) decreased, and hospital stay shortened.This study will be examining the use of regional anesthesia (infra-orbital and supra-orbital nerve blocks) combined with general anesthesia versus general anesthesia to observe the systemic opioid consumptions of adult transsphenoidal pituitary surgery patients. Secondary endpoints of the study will be: (1) presence of PONV, (2) time in PACU (post anesthesia care unit) and finally, (3) duration of hospital stay until discharge.

Inclusion criteria

• Adult age between 18 and 65
• American Society of Anesthesiology (ASA) 1-2
• Elective pituitary tumor surgery, tumor less than or equal to 2 cm diameter within the sella and no cavernous
• sinus invasion
• Single surgeon, Dr. Kunwar
• Male and female patients
• English speaking
• Informed consent
• Not on chronic pre-opertaive pain medications (non-narcotics) in the last 1 week prior to surgery
• No opioid pain medications pre-op in the last 1 month before surgery
• No abuse of recreational drugs (cocaine, methamphetamines, THC (tetrahydrocannabinol), opioids/heroin)
• No herbal medications for pain in the 1-month prior to surgery

Exclusion criteria

• Age less than 18 years
• Non-English speaking
• Allergy to: Ropivicaine
• Chronic pain condition, including idiopathic migraine as defined by the ICHD (International Classification of Headache Disorders) II criteria, requiring the use of pain medications
• Inability to comprehend or adhere to study protocol