Abstract
Nalbuphine is an agonist-antagonist opioid with adequate analgesic properties and few depressant effects on the respiratory system. However, there are no detailed reports available on cardiovascular effects of nalbuphine in dogs. The aim of this study was to assess the effects of a continuous rate infusion (CRI) of nalbuphine on left ventricular systolic and diastolic function of healthy sevoflurane-anesthetized dogs. Eighteen mixed-breed bitches aged 1–4 years and weighing 9.9 ± 3.8 kg were used. Dogs were randomly assigned to one of two groups: nalbuphine (GN, n = 9) and control (GC, n = 9). Anesthesia was induced and maintained with sevoflurane (2V%) followed by an intravenous (IV) bolus of nalbuphine (0.3 mg/kg) or 0.9% NaCl at equal volume and then CRI of nalbuphine (0.4 mg/kg/h) or 0.9% NaCl at an equal infusion rate. Echocardiographic and hemodynamic variables were determined at baseline and 20, 40, 60, and 80 minutes following start of CRI. No differences were found between groups for left ventricular systolic and diastolic variables obtained through conventional echocardiography and two-dimensional speckle tracking. Likewise, hemodynamic variables did not differ between groups. The E′/A′ ratio significantly increased at 20 minutes compared to baseline only in GN. Nalbuphine given at a CRI does not influence left ventricular systolic and diastolic function in healthy sevoflurane-anesthetized dogs.
Highlights
Nalbuphine is an opioid drug that acts as an agonist to κ receptors and antagonist to μ receptors, with potency and clinical analgesic effects similar to that of morphine [1]
Variables reflecting left ventricular volumes and systolic function, such as enddiastolic volume index (EDVI), end-systolic volume index (ESVI), ejection fraction (EF), Doppler ejection index (DEI), Doppler cardiac index (DCI), and S′ wave did not differ among time points compared to baseline or between groups (Table 1)
Hemodynamic variables heart rate (HR), mean arterial pressure (MAP), SAP, DAP, and peripheral vascular resistance index (PVRI) did not differ between groups or time points (Table 4) and SpO2 remained at 100% throughout the experiment in both groups
Summary
Nalbuphine is an opioid drug that acts as an agonist to κ receptors and antagonist to μ receptors, with potency and clinical analgesic effects similar to that of morphine [1]. An important advantage of nalbuphine is its minimal depressant effect on respiratory function. Nalbuphine can be used to reverse the respiratory depression caused by full μ agonists, while still providing desirable analgesia [2]. Some studies have shown that mammalian myocardium has opioid receptors μ, σ, and κ [3,4,5]. One of the most important myocardium opioid receptors is the kappa. Once stimulated, they can decrease the sarcoplasmic concentrations of calcium, leading to negative inotropic effects. No studies were found addressing the effects of a CRI of nalbuphine on left ventricular systolic and diastolic function of healthy dogs. A few studies demonstrated a decrease in mean arterial pressure (MAP) and heart rate (HR) with the use of nalbuphine in dogs [2, 7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
