Evaluation of the Antinociceptive Effect of Maropitant, a Neurokinin-1 Receptor Antagonist, in Cats Undergoing Ovariohysterectomy

Abstract

Maropitant is a neurokinin-1 (NK1) receptor antagonist that can be used for pain management. The objective of this study was to evaluate the effect of continuous infusion of two doses of maropitant on cardiorespiratory parameters and its postoperative analgesic effect in cats undergoing ovariohysterectomy. Thirty cats were randomly assigned to one of three groups (10 cats each group): the control group (CG) received a continuous infusion of 10 ml/kg/h Ringer’s lactate; GM30 and GM100 first received an intravenous (IV) bolus of 1 mg/kg maropitant; GM30 then received continuous infusion of 30 μg/kg/h maropitant; and GM100 then received continuous infusion of 100 μg/kg/h maropitant. The maropitant was diluted into Ringer’s lactate and the GM30 and GM100 also received fluids intraoperatively. In all groups, premedication included intramuscular injections of morphine and acepromazine, followed by induction with propofol and maintenance with isoflurane. Temperature, heart rate (HR), Doppler blood pressure (DBP), respiratory rate, oxygen saturation, and measuring the end-tidal carbon dioxide and isoflurane were monitored. Postoperative pain was evaluated using a visual analog scale and the UNESP-Botucatu multidimensional composite pain scale in cats; morphine was used for analgesic rescue. During the surgical procedure, cats in GM100 demonstrated lower HR and DBP than those in CG. With regard to the evaluation of postoperative pain, GM100 required the least frequent morphine rescue and less rescue analgesia compared with CG. In conclusion, cats in GM100 maintained lower DBP and HR and required lower analgesic rescue during the postoperative period. The results suggested that animals receiving maropitant bolus (1 mg/kg) plus (100 μg/kg/h) experienced greater postoperative comfort, reflected by the lesser need for analgesic rescue. The use of maropitant in surgical procedures in cats contributes to postoperative comfort.

Continuous Infusion of Ketamine and Lidocaine Either with or without Maropitant as an Adjuvant Agent for Analgesia in Female Dogs Undergoing Mastectomy

“…In the present study, there was a significant reduction in the postoperative pain intensity because the group receiving maropitant required a lower number of rescues. In the study using maropitant in ovariohysterectomy in cat, the results suggest that cats experienced greater comfort during the postoperative period because they required a lower number of analgesic rescues [ 10 ]. It was observed that the use of different methods of assessment of postoperative pain allowed veracity in the analysed values.…”

“…NK-1 receptor antagonists may be centrally applied as antiemetics and analgesics and for treating urinary incontinence. These agents may also be used at the peripheral level for treating inflammatory bowel diseases, arthritis, inflammation, and cystitis [ 8 – 10 ].…”

Synthesis and Pharmacological Evaluation of Hybrids Targeting Opioid and Neurokinin Receptors

“…The co-administration of NK1 antagonists together with opioids was considered an option in chronic pain management, since NK1 blockade might be able to reduce the development of opioid tolerance, physical dependence, and withdrawal [43,44]. In preclinical animal studies, NK1 antagonists showed a promising profile, attenuating the nociceptive responses caused by inflammation or nerve damage [15][16][17]45]. However, they failed to exhibit efficacy in clinical trials [46].…”

“…Antagonism at the NK1 blocks the signals induced by SP and can inhibit the enhanced secretion of SP and increased expression of NK1 in prolonged pain states. That makes NK1 antagonists potential therapeutic agents for pain relief [15][16][17].…”

The effect of intravenous maropitant on blood pressure in healthy awake and anesthetized dogs

“…Dogs receiving maropitant experience improved quality of anesthetic recovery and shortened time to return to postoperative feeding, which helps mitigate the negative energy balance associated with surgery and anesthesia [8]. Maropitant may also have a role in providing adjunct analgesia for visceral pain as it has been shown to decrease the anesthetic inhalant requirement during ovariohysterectomy in dogs and cats [9][10][11][12][13][14]. Due to the multiple benefits in anesthetic and surgical patients, maropitant is frequently incorporated into anesthetic protocols in canine and feline patients.…”