Analgesic efficacy of USG-guided bilateral sphenopalatine ganglion block versus no block in Endoscopic Sinus Surgery: A randomized control trial

The sphenopalatine ganglion (SPG) is one of the peripheral parasympathetic ganglia and associated with the general sensory fibres.1  It has been shown that SPG blockade provides postoperative analgesia and reduces the need for analgesics, and it has been claimed to be superior to general anaesthesia alone in nasal surgery.3 After Endoscopic Sinus Surgery performed under general anaesthesia; laryngospasm, nausea-vomiting, headache and sore throat are some of the common complications in the early recovery period. Despite the important developments in analgesia and surgical techniques, there is no consensus on the excessive use of drugs for pain control after Endoscopic Sinus Surgery.The aim of our study is to test the hypothesis that USG guided SPG blockade provides better analgesia in the first 24 h postoperatively than the control group in Endoscopic Sinus Surgery. There is no RCT where USG guided sphenopalatine ganglion blocks has been performed in Endoscopic Sinus Surgery and compared to the group with no block performed.

Primary Objective : To compare the total postoperative opioid consumption up to 24 hours

Secondary Objective (Optional): To compare the total intraoperative opioid consumption NRS scores at 1, 2, 6 and 24 hours postoperatively

Time to first rescue analgesia

Hemodynamic parameters at 0, 2, 6 and 24 hours

Study design: Our study will be a randomized, and double-blind study done on 58 subjects

Inclusion criteria - ASA I and II, 18-60 years of age, surgery lasting less than 3 hrs, male and female of BMI 18-30kg/m2

Exclusion criteria –History of severe liver, renal or cardiovascular disease or chronic pain disease, pre-existing neurological or psychiatric illness, any bleeding abnormality, allergy to the study drug, sensitivity to NSAIDs, hstory of alcohol or drug abuse or chronic use of analgesics, sedatives, opioids, or steroids and pregnant patients

After GA, the intervention group will be administered bilateral SPG block (Group S, n = 29) using USG and 4 mL of 0.5% bupivacaine and 0.5 mcg/kg bodyweight dexmedetomidine in a volume of 1 ml total solution of 5ml to each SPG site will deposited and the control group (Group C, n = 29) will not receive any block. SPG blockade will be performed by an anaesthesiologist who will not be taking part in observation and data collection.  The results will be evaluated by an anaesthesiologist who will not be involved in the study.

SPGB is expected to be effective in postoperative pain control in FESS surgery and provide less exposure to drug side effects by reducing postoperative analgesic consumption. It may reduce the incidence of laryngospasm, nausea and vomiting.