Sedative, hematologic and hemostatic effects of dexmedetomidine-butorphanol alone or in combination with ketamine in cats

Clinical Effects and Pharmacokinetic Profile of Intramuscular Dexmedetomidine (10 μg/kg) in Cats

This study investigated the pharmacokinetic profile of and pharmacodynamic response to dexmedetomidine administered intramuscularly (IM) at a dose of 10 μg/kg in healthy cats. Nine adult cats were evaluated before and after administration of the drug, with serial collections of plasma samples. Dexmedetomidine induced deep sedation, with a rapid onset of action and a duration of one hour, reaching a peak between 20 and 30 min after administration. The half-life (T½) was 70.2 ± 48 min, with a maximum concentration (Cmax) of 2.2 ± 1.9 ng/mL and time to reach maximum concentration (Tmax) of 26.4 ± 19.8 min. The area under the curve (AUC) was 167.1 ± 149.1 ng/mL*min, with a volume of distribution (Vd) of 2159.9 ± 3237.8 mL/kg and clearance (Cl) of 25.8 ± 33.0 mL/min/kg. There was a reduction in heart rate (HR) and respiratory rate (RR) in relation to the baseline, with a slight decrease in systolic (SBP), diastolic (DBP), and mean (MAP) blood pressure in the first hour. Blood glucose increased after 60 min. Dexmedetomidine proved to be effective and safe, with rapid absorption, metabolization, and elimination, promoting good sedation with minimal adverse effects after IM administration in healthy cats.

Use of Gabapentin or Alprazolam in Cats during Postoperative, Short-Term Hospitalization

This prospective, randomized study aimed to assess the anxiolytic efficacy of gabapentin or alprazolam in cats during short-term postoperative hospitalization. Sixty cats were randomly assigned to three groups (gabapentin-treated [100 mg per cat], alprazolam-treated [0.125 mg per cat], or placebo-treated), with treatments administered twice daily for two days. Stress levels were evaluated using Cat Stress Scores, serum cortisol, and glucose concentrations. Pain scores, food consumption, and adverse effects such as sedation were also monitored. Fifty-five cats completed the study. Both medications demonstrated similar reductions in stress levels. Cats receiving gabapentin had lower pain scores, while those receiving alprazolam exhibited significantly increased food intake on the first postoperative day. However, both medications resulted in comparable levels of sedation. In the context of postoperative hospitalization, pharmacological intervention with anxiolytics could be effective in reducing stress levels. Despite potential side effects, gabapentin and alprazolam may contribute to an improved quality of short-term hospitalization for cats.

Effects of intranasal and intramuscular dexmedetomidine in cats receiving total intravenous propofol anesthesia

Background and Aim:

The efficacy of intranasal (IN) dexmedetomidine in cats as a premedication remains elusive. Thus, this study aimed to compare the perioperative and sparing effects of IN and intramuscular (IM) dexmedetomidine administration on propofol requirements for anesthetic induction in cats.

Materials and Methods:

This study randomly assigned 16 cats into two groups of IN or IM dexmedetomidine at 20 μg/kg. Sedation scores and side effects were recorded at time points of 0, 5, 10, 15, and 20 min after the dexmedetomidine administration. Anesthesia was induced with intravenous (IV) 1% propofol by titrating a bolus of 2 mg every 45 s and the total dose of the administered IV propofol to achieve endotracheal intubation was recorded.

Results:

Cats receiving IM dexmedetomidine were significantly associated with higher sedation scores. All cats were sedated at 20 min after premedication; however, the average composite sedation scores in the IN group were significantly lower than those in the IM group during premedication. Pre-operative side effects, including vomiting, were more frequently observed in the IN group (5 cats, 62.5%) than in the IM group (3 cats, 37.5%; p < 0.05). Higher body temperature (>1°F compared to baseline) was more frequently observed in the IN group (6 cats, 75.0%) than in the IM group (1 cat, 12.5%; p < 0.05). The dosage of required propofol in the IN group was significantly higher (1.1 ± 0.3 mg/kg) than that in the IM group (0.7 ± 0.2 mg/kg; p < 0.05). The duration of general anesthesia was comparable between the groups.

Conclusion:

IN dexmedetomidine produces moderate sedation and cats may have side effects, including vomiting and higher body temperature. Higher sparing effects of propofol were identified in the IM group compared with the IN group. Nonetheless, IN administration of dexmedetomidine provides a noninvasive alternative to the IM route.

Hematological Parameters from the Feline Blood Donor to the Blood Unit: What Changes Are to Be Expected?

Simple Summary

Feline blood donation requires sedation to allow for good blood collection, avoiding venous damage and unnecessary donor stress. In the present study, we describe the variation of hematological parameters in a population of healthy blood-donor cats that underwent the same sedation protocol, including medetomidine, alfaxalone, and butorphanol. Significant differences in hematological parameters were observed between unsedated and sedated cats; particularly, the mean red blood cell count, hemoglobin concentration, hematocrit value, mean corpuscular volume, and red blood cells distribution width were significantly lower in sedated cats than in conscious ones, thus confirming that sedation is a critical procedure in cats. No significant differences for the main hematological parameters were observed between sedated cats and feline blood units, suggesting that the dilution with the conservative–anticoagulant solution (ratio 1:7) exerts negligible effects on these parameters with respect to samples of sedated animals.

Abstract

Feline blood donation requires sedation to allow for good blood collection, avoiding venous damage and unnecessary donor stress. In the present study, we describe the variation of hematological parameters in a population of 74 healthy blood-donor cats that underwent the same sedation protocol, including medetomidine, alfaxalone, and butorphanol. Changes in hematological parameters were evaluated in blood samples collected from conscious cats (group A), sedated cats (group B), and feline whole-blood units (FBUs) (group C). Significant differences were observed between unsedated and sedated cats: the mean RBC count, HGB, HCT, and RDW were significantly lower in sedated cats than in conscious ones, with a difference of 17.95%, 18.42%, 28.21%, and 10.00%, respectively. In accordance with previously reported data, our results confirm that sedation is a critical procedure in cats that can affect most of the hematological parameters. The second finding of our study is that no significant differences for the main hematological parameters were observed between sedated cats and FBUs, thus suggesting that the dilution with the conservative–anticoagulant solution exert negligible effects on these parameters with respect to samples of sedated animals. This hematological change must be taken into consideration since such parameters are important to define the quality of FBUs.

Feline procedural sedation and analgesia: When, why and how

PRACTICAL RELEVANCE

Procedural sedation and analgesia (PSA) describes the process of depressing a patient's conscious state to perform unpleasant, minimally invasive procedures, and is part of the daily routine in feline medicine. Maintaining cardiopulmonary stability is critical while peforming PSA.

CLINICAL CHALLENGES

Decision-making with respect to drug choice and dosage regimen, taking into consideration the cat's health status, behavior, any concomitant diseases and the need for analgesia, represents an everyday challenge in feline practice. While PSA is commonly perceived to be an uneventful procedure, complications may arise, especially when cats that were meant to be sedated are actually anesthetized.

AIMS

This clinical article reviews key aspects of PSA in cats while exploring the literature and discussing complications and risk factors. Recommendations are given for patient assessment and preparation, clinical monitoring and fasting protocols, and there is discussion of how PSA protocols may change blood results and diagnostic tests. An overview of, and rationale for, building a PSA protocol, and the advantages and disadvantages of different classes of sedatives and anesthetics, is presented in a clinical context. Finally, injectable drug protocols are reported, supported by an evidence-based approach and clinical experience.

Impact of preanaesthetic echocardiography on the planned anaesthetic management of cats

OBJECTIVE

To assess the impact of preanaesthetic echocardiography on the subsequent intended anaesthetic management plan in cats with incidental clinical findings that may indicate cardiac disease.

STUDY DESIGN

Clinical study involving cats undergoing echocardiography and subsequent anaesthesia.

ANIMALS

A total of 40 client-owned cats.

METHODS

Echocardiography was performed in conscious cats and the information was used to plan anaesthesia or sedation. An information sheet including relevant history, temperament, body condition score, clinical examination findings, current medication and results of any relevant tests such as haematology, biochemistry or Doppler blood pressure measurement was sent to three specialist anaesthetists and virtual case management plans were designed for each cat in two steps: step 1) anaesthetists were unaware of echocardiography results; and step 2) anaesthetists were aware of echocardiography results. In the second step the anaesthetists documented any changes to their original management plan, as either 'step-up' or 'step-down'.

RESULTS

Of the 40 cats, 26 had murmurs, four had a gallop rhythm, four had both findings and six had other findings. Pathology of potential haemodynamic significance was found on echocardiography in 23 cats, 17 of which anaesthetists had correctly identified as having disease before echocardiography. A proportion of cats with murmurs were subsequently deemed to have no significant pathology after echocardiography. Echocardiography findings in these cases were: dynamic left ventricular outflow tract obstruction (DLVOTO) without hypertrophy; DLVOTO without hypertrophy + dynamic right ventricular outflow tract obstruction (DRVOTO); DRVOTO; valvular dysplasia; normal. In a median of 26/40 (range 16-38) of cases, the anaesthetic plan was changed after provision of further information; in 15/40 (8-20) cases, this was a 'step-up' in care and in eight/40 (6-23) it was a 'step-down' in care. In cases with atrial enlargement (left atrium to aortic ratio of >1.6) and deemed at risk of cardiac failure, alpha-2 agonist use changed considerably with availability of echocardiography findings.

CONCLUSION

and clinical relevance Where there are abnormal cardiac findings on clinical examination in cats, echocardiography is required to accurately assess anaesthetic risk . The availability of echocardiographic information positively influences anaesthetic management.

Effect of non-steroidal anti-inflammatory drugs on postoperative respiratory and heart rate in cats subjected to ovariohysterectomy

Objectives The use of physiological parameters such as respiratory rate and heart rate to assess pain has long been discussed. The aim of the study was to compare postoperative respiratory rate and heart rate in cats subjected to flank ovariohysterectomy treated with a preoperative non-steroidal anti-inflammatory drug (NSAID) or no NSAID, and determine whether these parameters are suitable for postoperative pain assessment in cats. We hypothesised that cats without an NSAID would experience more postoperative pain, which may increase heart rate and respiratory rate. Methods A total of 168 female privately owned cats were studied. All cats were premedicated with medetomidine (0.08 mg/kg) and butorphanol (0.4 mg/kg) subcutaneously and anaesthesia was induced with intramuscular ketamine (5 mg/kg). Cats were divided into subgroups; controls (no NSAID) or cats given an NSAID, carprofen (4 mg/kg) or meloxicam (0.3 mg/kg), at premedication or induction of anaesthesia. Cats were subjected to flank ovariohysterectomy by the same surgeon. Atipamezole was administered 2.5 h after induction of anaesthesia. Respiratory rate and heart rate were measured 3.5 h after the induction of anaesthesia. Data were analysed using one-way ANOVA with mixed procedure and Tukey's adjustment method for multiplicity. Results The postoperative respiratory rate and heart rate per minute for all cats were 34.0 ± 8.6 and 167.5 ± 27.4, respectively. Neither respiratory rate nor heart rate differed significantly between the control group and the NSAID groups or between different time points of administration of NSAIDs. Conclusion and relevance Assuming there was less postoperative pain in the group administered NSAIDs, the results of the study presented no support for use of respiratory rate and heart rate as parameters for postoperative pain assessment in individual cats. Study limitations included a lack of pain scoring and baseline data for respiratory rate and heart rate.

AAFP Feline Anesthesia Guidelines

AIM

The overarching purpose of the AAFP Anesthesia Guidelines (hereafter referred to as the 'Guidelines') is to make anesthesia and sedation safer for the feline patient. Scope and accessibility: It is noteworthy that these are the first exclusively feline anesthesia guidelines authored by an expert panel, making them particularly useful as an extensively referenced, practical resource for veterinary practice teams. Because much of the key content is presented in tabular or visual format, the Guidelines have a high level of accessibility and convenience that invites regular usage. While the recommendations in the Guidelines focus primarily on client-owned cats, the content is also applicable to community-sourced animals with an unknown medical history.

Efeitos de dois protocolos de sedação sobre as variáveis bioquímicas em gatos

RESUMO A utilização de protocolos de sedação como auxílio na contenção de felinos para realização de coletas de sangue é de grande importância, porém a utilização de alguns fármacos pode alterar resultados e a interpretação deles. Por outro lado, a contenção física pode gerar intenso estresse, especialmente em felinos, o que também pode interferir nos resultados. Este estudo teve como objetivo avaliar exames de bioquímica clínica sob o uso de contenção física e química em gatos submetidos a dois protocolos de sedação. Foram utilizados 50 gatos, 26 fêmeas e 24 machos, sem raça definida, submetidos a contenção física e, imediatamente após, a dois protocolos de sedação, DB (dexmedetomidina 5µg/kg e butorfanol 0,3mg/kg) e DBC (dexmedetomidina 5µg/kg, butorfanol 0,3mg/kg e cetamina 3mg/kg), aplicados por via intramuscular. Amostras de sangue foram coletadas após a contenção física e, em seguida, após o uso de um dos protocolos de sedação. Foram avaliados: ureia, creatinina, alaninoaminotransferase (ALT), fosfatase alcalina, proteína sérica total (PST), albumina, globulinas, colesterol, triglicérides, cálcio, magnésio e cloretos de amostras de soro, lactato e glicose de amostras de plasma fluoretado. Foi encontrada diferença estatística entre grupos para albumina, triglicérides, PST e colesterol, com maiores valores sendo encontrados no grupo DBC. Entre momentos, houve diferença para colesterol e fosfatase alcalina, com maiores valores no momento contenção física somente no grupo DBC. Já a glicose teve maiores valores após a sedação em ambos os grupos. O estudo revelou que o uso destes protocolos implica restrições para alguns parâmetros bioquímicos aqui estudados e que suas interpretações devem ser avaliadas cuidadosamente.