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Postoperative nausea and vomiting (PONV) is prevalent in surgical patients with known risk factors: general anesthesia, female, nonsmoker, motion sickness history, and PONV history. Common treatment involves ondansetron; however, the effects are short-lived, and supplemental medication may be required. Meclizine, a long-acting drug with a low side-effect profile, may be ideal in combination with ondansetron for at-risk patients.
We randomized 77 subjects scheduled for general anesthesia and screened for 4 of 5 PONV risk factors for experimental or control group assignment. Severity of PONV was measured using a 0 to 10 verbal numeric rating scale (VNRS). Other measured variables included time to onset and incidence of PONV and total antiemetic requirements.
No significant differences in demographics (excluding weight), surgical or anesthesia time, analgesic requirements, or nausea incidence in the postanesthesia care unit (PACU) and same-day surgery unit were noted. The meclizine group had lower VNRS scores in the PACU at 15 (P = .013) and 45 (P = .006)minutes following rescue treatment. The incidence of nausea was lower in the meclizine vs placebo group (10% vs 29%) following discharge (P = .038).
Prophylactic meclizine resulted in lower incidence and severity of PONV in a high-risk population, especially after rescue treatment.
Key words: Meclizine, motion sickness, postoperative nausea and vomiting (PONV).
The incidence of PONV in a general anesthesia surgical population ranges from 20% to 30%, resulting in higher overall institutional and patient costs and lower patient satisfaction. 1-6 The risk of PONV increases even further when certain risk factors are present. These risk factors include general anesthesia, female gender, nonsmoker, history of PONV, and history of motion sickness. 1,2,7-9 In fact, it has been noted that the incidence of PONV increases exponentially from 17% when no risk factors are present to as high as 87% when all 5 risk factors are present.2,8 Therefore, it is imperative that anesthesia providers investigate methods to decrease the overall incidence of PONV, especially when some or all of these risk factors are present.
Postoperative nausea and vomiting has a multifactorial pathogenesis with activation of target receptors in the chemoreceptor trigger zone (CTZ) and afferent impulses relayed to the vestibular center.3 Activation of dopamine, opioid, cholinergic, histamine, and serotonin receptors in the CTZ have traditionally been antagonized with...