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Journal of the American Veterinary... Apr 2015To investigate hemodynamic effects of acepromazine and dexmedetomidine premedication in dogs undergoing general anesthesia induced with propofol and maintained with... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
To investigate hemodynamic effects of acepromazine and dexmedetomidine premedication in dogs undergoing general anesthesia induced with propofol and maintained with isoflurane in oxygen and assess the influence of these drugs on oxygen-carrying capacity and PCV.
DESIGN
Prospective, randomized crossover study.
ANIMALS
6 healthy adult dogs.
PROCEDURES
Dogs received acepromazine (0.05 mg/kg [0.023 mg/lb]) or dexmedetomidine (15.0 μg/kg [6.82 μg/lb]) IM. Fifteen minutes later, anesthesia was induced with propofol and maintained at end-tidal isoflurane concentration of 1.28% (1 minimum alveolar concentration) for 30 minutes. Hemodynamic variables were recorded at predetermined times. The experiment was repeated 48 hours later with the alternate premedication. Results were analyzed by repeated-measures ANOVA with a mixed-models procedure.
RESULTS
Bradycardia, hypertension, and significant cardiac output (CO) reduction developed after dexmedetomidine premedication but improved during isoflurane anesthesia. Hypotension developed after acepromazine administration and persisted throughout the isoflurane maintenance period, but CO was maintained throughout the anesthetic period when dogs received this treatment. Oxygen delivery and consumption were not different between treatments at most time points, whereas arterial oxygen content was lower with acepromazine premedication owing to lower PCV during isoflurane anesthesia.
CONCLUSIONS AND CLINICAL RELEVANCE
Acepromazine exacerbated hypotension, but CO did not change in dogs anesthetized with propofol and isoflurane. Dexmedetomidine reduced CO but prevented propofol-isoflurane-induced hypotension. In general, oxygen-carrying capacity and PCV were higher in dexmedetomidine-treated than in acepromazine-treated dogs anesthetized with propofol and isoflurane.
Topics: Acepromazine; Anesthesia, Inhalation; Animals; Blood Pressure; Cardiac Output; Cross-Over Studies; Dexmedetomidine; Dogs; Female; Isoflurane; Male; Premedication
PubMed: 25794125
DOI: 10.2460/javma.246.7.754 -
Frontiers in Veterinary Science 2021The lack of standardization of sedation scales in horses limits the reproducibility between different studies. This prospective, randomized, blinded, horizontal and...
The lack of standardization of sedation scales in horses limits the reproducibility between different studies. This prospective, randomized, blinded, horizontal and controlled trial aimed to validate a scale for sedation in horses (EquiSed). Seven horses were treated with intravenous detomidine in low/high doses alone (DL 2.5 μg/kg + 6.25 μg/kg/h; DH 5 μg/kg +12.5 μg/kg/h) or associated with methadone (DLM and DHM, 0.2 mg/kg + 0.05 mg/kg/h) and with low (ACPL 0.02 mg/kg) or high (ACPH 0.09 mg/kg) doses of acepromazine alone. Horses were filmed at (i) baseline (ii) peak, (iii) intermediate, and (iv) end of sedation immediately before auditory, visual and pressure stimuli were applied and postural instability evaluated for another study. Videos were randomized and blindly evaluated by four evaluators in two phases with 1-month interval. Intra- and interobserver reliability of the sum of EquiSed (Intraclass correlation coefficient) ranged between 0.84-0.94 and 0.45-0.88, respectively. The criterion validity was endorsed by the high Spearman correlation between the EquiSed and visual analog (0.77), numerical rating (0.76), and simple descriptive scales (0.70), and average correlation with head height above the ground (HHAG) (-0.52). The Friedman test confirmed the EquiSed responsiveness over time. The principal component analysis showed that all items of the scale had a load factor ≥ 0.50. The item-total Spearman correlation for all items ranged from 0.3 to 0.5, and the internal consistency was good (Cronbach's α = 0.73). The area under the curve of EquiSed HHAG as a predictive diagnostic measure was 0.88. The sensitivity of the EquiSed calculated according to the cut-off point (score 7 of the sum of the EquiSed) determined by the receiver operating characteristic curve, was 96% and specificity was 83%. EquiSed has good intra- and interobserver reliabilities and is valid to evaluate tranquilization and sedation in horses.
PubMed: 33665216
DOI: 10.3389/fvets.2021.611729 -
Canadian Journal of Veterinary Research... Oct 2016The sedative effect of acepromazine combined with 2 doses of tramadol [3 and 5 mg/kg body weight (BW)] was compared with the sedative effect of acepromazine alone in... (Randomized Controlled Trial)
Randomized Controlled Trial
The sedative effect of acepromazine combined with 2 doses of tramadol [3 and 5 mg/kg body weight (BW)] was compared with the sedative effect of acepromazine alone in dogs and the effects of each sedative protocol on cardiorespiratory variables were examined. This was a prospective, randomized, blinded, crossover study. Each of 6 dogs received 3 treatments at 1-week intervals. During all anesthetic episodes, dogs received 0.05 mg/kg BW acepromazine. Approximately 25 min later, dogs were given physiological saline (control) or tramadol [3 mg/kg BW (TR3) or 5 mg/kg BW (TR5)]. All drugs were administered intravenously. Variables evaluated included heart rate (HR), respiratory rate (RR), systolic, mean, and diastolic blood pressures (SAP, MAP, and DAP), and sedation [by use of a simple descriptive scale (SDS, range: 0 to 3) and a numeric rating scale (NRS, range: 0 to 10)]. Variables were recorded 25 min after acepromazine and for 80 min after saline or tramadol. Acepromazine administration resulted in mild sedation in most dogs and decreased RR, SAP, MAP, and DAP in all treatments. Tramadol administration did not significantly increase SDS or NRS scores compared to acepromazine alone. The only exception to this rule was observed at 20 min after TR3, when NRS was higher in this group than in the control treatment. Administration of tramadol (TR3 and TR5) decreased HR. Under the conditions of this study, sedation induced by acepromazine with tramadol was similar to that of acepromazine alone. The main adverse effects of the combination were a decrease in blood pressure and HR, without clinical significance.
Topics: Acepromazine; Analgesics, Opioid; Animals; Body Weight; Conscious Sedation; Cross-Over Studies; Dogs; Drug Synergism; Female; Hypnotics and Sedatives; Male; Tramadol
PubMed: 27733788
DOI: No ID Found -
Veterinary Record Open 2018To evaluate the combined effect of intramuscular acepromazine and methadone on tear production in dogs undergoing general anaesthesia for elective, non-ocular procedures.
OBJECTIVES
To evaluate the combined effect of intramuscular acepromazine and methadone on tear production in dogs undergoing general anaesthesia for elective, non-ocular procedures.
DESIGN
Prospective, non-randomised, pre-post treatment study.
SETTING
Patients were recruited from a referral practice in the UK.
METHODS
Thirty client-owned dogs were enrolled in this study and received a combined intramuscular premedication of methadone (0.3 mg/kg) and acepromazine (0.02 mg/kg) before general anaesthesia for elective, non-ocular procedures. Full ophthalmic examination was performed and tear production was quantified using the Schirmer tear test-1 (STT-1). On the day of general anaesthesia, an STT-1 was performed before (STT-1a) and after (STT-1b) intramuscular premedication with methadone/acepromazine.
RESULTS
Using a general linear model, a significant effect on STT-1 results was found for premedication with methadone/acepromazine (P=0.013), but not eye laterality (P=0.527). Following premedication, there was a significant reduction observed in the mean STT-1 readings of left and right eyes between STT-1a (20.4±2.8 mm/min) and STT-1b (16.9±4.1 mm/min; P<0.001). Significantly more dogs had an STT-1 reading less than 15 mm/min in one or both eyes after premedication (30 per cent; 9/30 dogs) compared with before premedication (6.7 per cent; 2/30 dogs; P=0.042).
CONCLUSIONS
An intramuscular premedication of methadone and acepromazine results in a decrease in tear production in dogs before elective general anaesthesia. This may contribute to the risk of ocular morbidities, such as corneal ulceration, particularly in patients with lower baseline tear production.
PubMed: 30613403
DOI: 10.1136/vetreco-2018-000298 -
Animals : An Open Access Journal From... Nov 2021Dexmedetomidine is commonly used in small animal anesthesia for its potent sedative and analgesic properties; however, concerns regarding its cardiovascular effects... (Review)
Review
Dexmedetomidine is commonly used in small animal anesthesia for its potent sedative and analgesic properties; however, concerns regarding its cardiovascular effects prevent its full adoption into veterinary clinical practice. This meta-analysis was to determine the effects of dexmedetomidine on sedation, analgesia, cardiovascular and adverse reactions in dogs compared to other premedications. Following the study protocol based on the Cochrane Review Methods, thirteen studies were included in this meta-analysis ultimately, involving a total of 576 dogs. Dexmedetomidine administration probably improved in sedation and analgesia in comparison to acepromazine, ketamine and lidocaine (MD: 1.96, 95% CI: [-0.08, 4.00], = 0.06; MD: -0.95, 95% CI: [-1.52, -0.37] = 0.001; respectively). Hemodynamic outcomes showed that dogs probably experienced lower heart rate and higher systolic arterial blood pressure and mean arterial blood pressure with dexmedetomidine at 30 min after premedication (MD: -13.25, 95% CI: [-19.67, -6.81], < 0.0001; MD: 7.78, 95% CI: [1.83, 13.74], = 0.01; MD: 8.32, 95% CI: [3.95, 12.70], = 0.0002; respectively). The incidence of adverse effects was comparable between dexmedetomidine and other premedications (RR = 0.86, 95% CI [0.58, 1.29], = 0.47). In summary, dexmedetomidine provides satisfactory sedative and analgesic effects, and its safety is proved despite its significant hemodynamic effects as part of balanced anesthesia of dogs.
PubMed: 34827988
DOI: 10.3390/ani11113254 -
Veterinary Anaesthesia and Analgesia May 2018To compare the effects of alfaxalone and propofol, with and without acepromazine and butorphanol followed by doxapram, on laryngeal motion and quality of laryngeal... (Comparative Study)
Comparative Study Randomized Controlled Trial
OBJECTIVE
To compare the effects of alfaxalone and propofol, with and without acepromazine and butorphanol followed by doxapram, on laryngeal motion and quality of laryngeal examination in dogs.
STUDY DESIGN
Randomized, crossover, blinded study.
ANIMALS
Ten female Beagle dogs, aged 11-13 months and weighing 7.2-8.6 kg.
METHODS
The dogs were administered four intravenous (IV) treatments: alfaxalone (ALF), alfaxalone+acepromazine and butorphanol (ALF-AB), propofol (PRO) and propofol+AB (PRO-AB). AB doses were standardized. Dogs were anesthetized 5 minutes later by administration of alfaxalone or propofol IV to effect. Arytenoid motion during maximal inspiration and expiration was captured on video before and after IV doxapram (0.25 mg kg). The change in rima glottidis surface area (RGSA) was calculated to measure arytenoid motion. An investigator blinded to the treatment scored laryngeal examination quality.
RESULTS
A 20% increase in RGSA was the minimal arytenoid motion that was detectable. RGSA was significantly less in ALF before doxapram compared with all other treatments. A <20% increase in RGSA was measured in eight of 10 dogs in PRO and in all dogs in ALF before doxapram. After doxapram, RGSA was significantly increased for PRO and ALF; however, 20% of dogs in PRO and 50% of dogs in ALF still had <20% increase in RGSA. A <20% increase in RGSA was measured in five of 10 dogs in PRO-AB and ALF-AB before doxapram. All dogs in PRO-AB and ALF-AB with <20% increase in RGSA before doxapram had ≥20% increase in RGSA after doxapram. Examination quality was significantly better in PRO-AB and ALF-AB.
CONCLUSIONS AND CLINICAL RELEVANCE
The use of acepromazine and butorphanol improved the quality of laryngeal examination. Any negative impact on arytenoid motion caused by these premedications was overcome with doxapram. Using either propofol or alfaxalone alone is not recommended for the evaluation of arytenoid motion.
Topics: Acepromazine; Anesthesia; Anesthetics; Anesthetics, Combined; Animals; Butorphanol; Cross-Over Studies; Dog Diseases; Dogs; Doxapram; Female; Laryngoscopy; Larynx; Physical Examination; Pregnanediones; Propofol; Vocal Cord Paralysis
PubMed: 29426677
DOI: 10.1016/j.vaa.2017.08.014 -
BMC Veterinary Research Apr 2017The aim of this study was to assess validation evidence for a sedation scale for dogs. We hypothesized that the chosen sedation scale would be unreliable when used by...
BACKGROUND
The aim of this study was to assess validation evidence for a sedation scale for dogs. We hypothesized that the chosen sedation scale would be unreliable when used by different raters and show poor discrimination between sedation protocols. A sedation scale (range 0-21) was used to score 62 dogs scheduled to receive sedation at two veterinary clinics in a prospective trial. Scores recorded by a single observer were used to assess internal consistency and construct validity of the scores. To assess inter-rater reliability, video-recordings of sedation assessment were randomized and blinded for viewing by 5 raters untrained in the scale. Videos were also edited to allow assessment of inter-rater reliability of an abbreviated scale (range 0-12) by 5 different raters.
RESULTS
Both sedation scales exhibited excellent internal consistency and very good inter-rater reliability (full scale, intraclass correlation coefficient [ICC] = 0.95; abbreviated scale, ICC = 0.94). The full scale discriminated between the most common protocols: dexmedetomidine-hydromorphone (median [range] of sedation score, 11 [1-18], n = 20) and acepromazine-hydromorphone (5 [0-15], n = 36, p = 0.02).
CONCLUSIONS
The hypothesis was rejected. Full and abbreviated scales showed excellent internal consistency and very good reliability between multiple untrained raters. The full scale differentiated between levels of sedation.
Topics: Animals; Conscious Sedation; Dogs; Female; Hypnotics and Sedatives; Male; Observer Variation; Prospective Studies; Random Allocation; Videotape Recording
PubMed: 28420386
DOI: 10.1186/s12917-017-1027-2 -
Veterinary Medicine and Science Jul 2021A great number of sedatives and anaesthetics have been used to perform surgeries or routine ophthalmologic examinations in animals and sometimes the combination of these...
BACKGROUND
A great number of sedatives and anaesthetics have been used to perform surgeries or routine ophthalmologic examinations in animals and sometimes the combination of these medicines has more suitable effects than each one alone.
OBJECTIVES
This paper aims to explore the main effects of Medetomidine + Acepromazine, Dexmedetomidine + Acepromazine on intraocular pressure, tear secretion and pupil diameter.
METHODS
To accomplish the aforementioned aim, 32 adult dogs (aged one-to-three-years-old) were clinically examined. Dogs were divided into four groups consisting of group DA, Dexmedetomidine (5 µg/kg) + Acepromazine (0.05 mg/kg); Group D, Dexmedetomidine (5 µg/kg); Group M, Medetomidine (10 µg/kg); Group MA, Medetomidine (10 µg/kg) + Acepromazine (0.05 mg/kg). The ocular factors including tear production, pupil diameter and intraocular pressure of both right and left eyes were first measured and then recorded in each dog at time T (-15 min). Afterwards, the drugs were administered intramuscularly, based on which the ocular factors were re-measured at T (+5 min), T (+15 min) and T (+20 min). All four groups showed a reduction in intraocular pressure, which was significant in DA, D and M groups.
RESULTS
Furthermore, there was a fluctuation in the amount of tear secretion in DA and D groups (increase and then decrease), as well as a significant reduction in M and MA groups. Decreasing in pupil diameter also occurred in all four groups, but the reduction was significant only in DA and MA groups.
CONCLUSION
According to the results obtained, as the changes caused by the systemic administration of the above drug compounds did not exceed the physiological range, it can be concluded that these combinations could be utilized as suitable sedatives or pre-anaesthetic compounds in the eye surgeries.
Topics: Acepromazine; Animals; Dexmedetomidine; Dogs; Drug Combinations; Hypnotics and Sedatives; Intraocular Pressure; Medetomidine; Pupil; Tears
PubMed: 33751831
DOI: 10.1002/vms3.467 -
American Journal of Veterinary Research Nov 2023To elucidate the cardiovascular effects of escalating doses of phenylephrine and norepinephrine in dogs receiving acepromazine and isoflurane.
OBJECTIVE
To elucidate the cardiovascular effects of escalating doses of phenylephrine and norepinephrine in dogs receiving acepromazine and isoflurane.
ANIMALS
8 beagles aged 1 to 2 years (7.4 to 11.2 kg).
METHODS
All dogs received acepromazine 0.01 mg/kg, propofol 4 to 5 mg/kg, and isoflurane and were mechanically ventilated. Mean arterial pressure (MAP) from a femoral artery catheter and continuous electrocardiogram were recorded. Cardiac output (CO) was measured with transpulmonary thermodilution. Systemic vascular resistance (SVR), global end-diastolic volume (GEDV), and global ejection fraction (GEF) were subsequently calculated. Phenylephrine and norepinephrine were infused in random order at 0.07, 0.3, 0.7, and 1.0 μg/kg/min. All variables were measured after 15 minutes of each infusion rate. The effects of dose, agent, and their interaction on the change of each variable were evaluated with mixed-effect models. A P < .05 was used for significance.
RESULTS
Atrial premature complexes occurred in 3 dogs during norepinephrine infusion at doses of 0.3, 0.7, and 1 μg/kg/min; no dysrhythmias were seen with phenylephrine administration. MAP increased during dose escalation (P < .0001) within each agent and did not differ between agents (P = .6). The decrease in HR was greater for phenylephrine (P < .0001). Phenylephrine decreased CO and GEF and increased GEDV and SVR (all P < .03). Norepinephrine decreased the SVR and increased CO, GEDV, and GEF (all P < .03).
CLINICAL RELEVANCE
Our results confirm that phenylephrine increases arterial pressures mainly through vasoconstriction in acepromazine-premedicated dogs while norepinephrine, historically considered a vasopressor, does so primarily through an increase in inotropism.
Topics: Animals; Dogs; Acepromazine; Isoflurane; Norepinephrine; Phenylephrine; Blood Pressure
PubMed: 37657733
DOI: 10.2460/ajvr.23.06.0147 -
The Korean Journal of Physiology &... Jan 2017The effects of acepromazine on human ether-à-go-go-related gene (hERG) potassium channels were investigated using whole-cell voltage-clamp technique in human embryonic...
The effects of acepromazine on human ether-à-go-go-related gene (hERG) potassium channels were investigated using whole-cell voltage-clamp technique in human embryonic kidney (HEK293) cells transfected with hERG. The hERG currents were recorded with or without acepromazine, and the steady-state and peak tail currents were analyzed for the evaluating the drug effects. Acepromazine inhibited the hERG currents in a concentration-dependent manner with an IC value of 1.5 µM and Hill coefficient of 1.1. Acepromazine blocked hERG currents in a voltage-dependent manner between -40 and +10 mV. Before and after application of acepromazine, the half activation potentials of hERG currents changed to hyperpolarizing direction. Acepromazine blocked both the steady-state hERG currents by depolarizing pulse and the peak tail currents by repolarizing pulse; however, the extent of blocking by acepromazine in the repolarizing pulse was more profound than that in the depolarizing pulse, indicating that acepromazine has a high affinity for the open state of the channels, with a relatively lower affinity for the closed state of hERG channels. A fast application of acepromazine during the tail currents inhibited the open state of hERG channels in a concentration-dependent. The steady-state inactivation of hERG currents shifted to the hyperpolarized direction by acepromazine. These results suggest that acepromazine inhibits the hERG channels probably by an open- and inactivated-channel blocking mechanism. Regarding to the fact that the hERG channels are the potential target of drug-induced long QT syndrome, our results suggest that acepromazine can possibly induce a cardiac arrhythmia through the inhibition of hERG channels.
PubMed: 28066143
DOI: 10.4196/kjpp.2017.21.1.75