The effect of maropitant on sedation, propofol requirements, and cardiovascular function at induction of anesthesia in healthy cats.

The objective of this study was to evaluate the sedative effects, propofol requirements, and cardiorespiratory effects following maropitant administration in healthy cats. Maropitant is a selective neurokinin-1 receptor antagonist licensed for use as an antiemetic in dogs and cats. Recent studies have highlighted the ability of maropitant to reduce inhalational anesthetic requirements during surgery from presumptive analgesic effects. Sedative properties of maropitant and its possible reduction of injectable anesthetic requirements have not yet been evaluated. Twenty adult purpose-bred domestic shorthair cats were randomized to receive maropitant (n = 10) or physiologic saline (n = 10) prior to anesthetic induction with propofol intravenously (IV). Cats were premedicated with butorphanol [0.4 mg/kg body weight (BW)] and alfaxalone [2 mg/kg BW intramuscularly (IM)]. Maropitant (1 mg/kg BW) or physiologic saline (0.1 mL/kg BW) was administered IV 10 min prior to anesthetic induction with propofol and subsequent orotracheal intubation. Sedation scores were recorded before premedication, after premedication, and 10 min after maropitant or saline administration. Propofol dose requirements to achieve orotracheal intubation were recorded. Heart rate (HR), respiratory rate (RR), and arterial blood pressures were measured before and after administration of maropitant or saline, after administration of propofol, and following intubation. Propofol dose requirements did not differ between groups, with mean ± standard deviation doses of 5.2 ± 2.1 mg/kg BW and 5.6 ± 1.3 mg/kg BW for maropitant and saline groups, respectively. Sedation scores and cardiorespiratory variables did not differ between groups at any timepoint. Maropitant administration prior to anesthetic induction with propofol did not affect sedation scores, propofol requirements, or cardiorespiratory variables.