According to a prospective experimental study published in BMC Surgery, the use of intravenous (IV) injection of butorphanol (an opioid analgesic) dosed at 7.5 μg/kg along with propofol can serve as an ideal dosage for patients undergoing gastroscopy and colonoscopy. Shun Lv and researchers investigated the anesthetic effect of different doses of butorphanol in individuals undergoing diagnostic procedures for examining parts of the digestive tract.

Overall, 480 patients undergoing these procedures were enrolled. They were allocated in 4 groups of varying doses of butorphanol (Group A = 2.5 μg per kg, Group B = 5 μg per kg, Group C = 7.5 μg per kg, and Group D = 10 μg per kg). Butorphanol was used 5 minutes prior to propofol infusion. The occurrence of body movement was considered as the primary outcome. 

Postoperative recovery time, duration of Post-Anesthesia Care Unit (PACU) stay, the total dose of propofol, and the occurrence of intraoperative low level of oxygen in the blood (hypoxemia), pain due to propofol injection, cough, postoperative nausea and vomiting, drowsiness, and dizziness were all considered as the secondary outcomes.

As compared to groups A and B, the patients in groups C and D had a lower incidence of body movement and propofol dose. Also, groups B, C, and D had lower incidence and intensity of propofol injection pain and cough compared to group A. The duration of PACU stay, postoperative drowsiness and dizziness were greater in Group D as compared to groups A, B, and C (Table 1).

A combination of butorphanol and propofol can safely suppress propofol injection pain and lowers the frequency of dizziness and drowsiness, the study researchers noted.