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Veterinary Anaesthesia and Analgesia Sep 2017To compare incidence and duration of postinduction apnoea in dogs after premedication with methadone and acepromazine (MA) or methadone and dexmedetomidine (MD) followed... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVE
To compare incidence and duration of postinduction apnoea in dogs after premedication with methadone and acepromazine (MA) or methadone and dexmedetomidine (MD) followed by induction with propofol (P) or alfaxalone (A).
STUDY DESIGN
Prospective, randomized clinical trial.
ANIMALS
A total of 32 American Society of Anesthesiologists class I dogs (15 females, 17 males), aged between 4 months and 4 years, weighing between 3 and 46 kg.
METHODS
Dogs were randomly allocated to be administered MA+P, MA+A, MD+P or MD+A (methadone 0.5 mg kg and acepromazine 0.05 mg kg or dexmedetomidine 5 μg kg). Induction agents were administered intravenously via syringe driver (P at 4 mg kg minute or A at 2 mg kg minute) until successful endotracheal intubation and the endotracheal tube connected to a circle system with oxygen flow at 2 L minute. Oxygen saturation of haemoglobin (SpO), end tidal partial pressure of carbon dioxide and respiratory rate were monitored continuously. If apnoea (≥ 30 seconds without breathing) occurred, the duration until first spontaneous breath was measured. If SpO decreased below 90% the experiment was stopped and manual ventilation initiated. Data were analysed with general linear models with significance set at p ≤ 0.05.
RESULTS
There was no statistical difference in the incidence (11 of 16 dogs in A groups and 12 of 16 dogs in P groups), or mean ± standard deviation duration (A groups 125 ± 113 seconds, P groups 119 ± 109 seconds) of apnoea. The SpO of one dog in the MD+P group decreased below 90% during the apnoeic period.
CONCLUSIONS AND CLINICAL RELEVANCE
Propofol and alfaxalone both cause postinduction apnoea and the incidence and duration of apnoea is not influenced by the use of acepromazine or dexmedetomidine in premedication. Monitoring of respiration is recommended when using these premedication and induction agent combinations.
Topics: Acepromazine; Anesthesia, General; Anesthetics, Combined; Animals; Apnea; Carbon Dioxide; Dexmedetomidine; Dogs; Female; Intubation, Intratracheal; Male; Preanesthetic Medication; Pregnanediones; Propofol; Respiratory Rate
PubMed: 28927811
DOI: 10.1016/j.vaa.2016.10.004 -
Veterinary Anaesthesia and Analgesia Nov 2022To acquire information about anesthesia and analgesia protocols used by United States (US) veterinarians in primary care practices when performing routine...
OBJECTIVE
To acquire information about anesthesia and analgesia protocols used by United States (US) veterinarians in primary care practices when performing routine ovariohysterectomy in dogs.
STUDY DESIGN
Cross-sectional survey.
POPULATION
Primary care veterinarians in the US.
METHODS
An online anonymous survey, originally created in New Zealand, was modified with permission and made available to Veterinary Information Network (VIN) members. The survey asked questions about performing ovariohysterectomy in healthy adolescent dogs in the categories of preanesthetic evaluation, premedication and induction protocols, maintenance protocols and monitoring equipment, and postoperative analgesic and sedation protocols and pain assessments.
RESULTS
A total of 1213 US veterinarians completed the survey. Respondents (n; %) reported performing preoperative laboratory tests [packed cell volume (135; 11%), complete blood cell count (889; 73%) and biochemistry panels (1057; 87%)] and preanesthetic examinations on the morning of surgery (1083; 90%). The most commonly administered drugs for premedication were acepromazine (512; 42%), hydromorphone (475; 39%) or butorphanol (463; 38%), with propofol (637; 67%) for induction of anesthesia and isoflurane (882; 73%) for maintenance of anesthesia. Most veterinarians reported placing intravenous catheters (945; 78%), administering electrolyte solutions (747; 67%) and providing heat support (1160; 96%). Perioperative and postoperative analgesia included local anesthetics (545; 45%), opioids (844; 70%) and non-steroidal anti-inflammatory drugs (NSAIDs) (953; 79%); NSAIDs were dispensed for home use (985; 81%). Dogs were most frequently discharged on the day of surgery (1068; 88%) and the owners were contacted (914; 75%) for follow-up within 1-2 days.
CONCLUSIONS AND CLINICAL RELEVANCE
Anesthetic management for routine ovariohysterectomy in dogs varies among US veterinary VIN members. Information from this study is useful for all veterinarians for comparison with their practice management and for teachers of veterinary anesthesia to continue to emphasize options for analgesia.
Topics: Female; Dogs; United States; Animals; Cross-Sectional Studies; Anesthesia; Analgesics; Hysterectomy; Pain; Anesthetics, Local; Anti-Inflammatory Agents, Non-Steroidal; General Practice; Pain, Postoperative; Ovariectomy; Dog Diseases
PubMed: 36038461
DOI: 10.1016/j.vaa.2022.07.010 -
Veterinary Anaesthesia and Analgesia Nov 2020To evaluate the effects of nalbuphine, butorphanol and morphine combined with acepromazine on intraoperative and early postoperative pain management in dogs anesthetized...
OBJECTIVE
To evaluate the effects of nalbuphine, butorphanol and morphine combined with acepromazine on intraoperative and early postoperative pain management in dogs anesthetized for ovariohysterectomy.
STUDY DESIGN
Prospective, randomized blinded clinical study.
ANIMALS
A total of 48 healthy female dogs of different breeds, aged 1-6 years, weighing (mean ± standard deviation) 14.5 ± 4.8 kg.
METHODS
Dogs were randomly assigned into four groups to be intravenously administered nalbuphine (0.5 mg kg; group N0.5), nalbuphine (1.0 mg kg; group N1.0), butorphanol (0.4 mg kg; group B0.4) or morphine (0.2 mg kg; group M0.2) combined with acepromazine (0.02 mg kg) prior to propofol and isoflurane for anesthesia. Heart rate (HR), respiratory rate, systolic arterial pressure and rectal temperature (RT) were recorded at time points during anesthesia. A dynamic interactive visual analog scale applied in three phases (DIVAS I, II and III) and the modified Glasgow composite measure pain scale were used to assess pain before premedication and 1, 2, 3, 4, 5 and 6 hours after extubation. Administration of rescue analgesia was recorded.
RESULTS
At the left ovarian pedicle ligation, HR was higher in N1.0 than in B0.4 (p = 0.020). RT decreased significantly by the end of surgery in N0.5 (p = 0.043) and B0.4 (p = 0.010). Rescue analgesia was administered postoperatively over 6 hours to eight, seven, nine and 10 dogs in N0.5, N1.0, B0.4 and M0.2, respectively (p = 0.57). DIVAS II was higher in B0.4 than in N1.0 at 2 and 3 hours (p = 0.038 and p = 0.002, respectively) and N0.5 at 3 hours (p = 0.003).
CONCLUSIONS AND CLINICAL RELEVANCE
At the doses used, all premedication protocols provided insufficient intraoperative analgesia, with minimal clinical differences between groups. No premedication provided satisfactory analgesia in the first 6 hours postoperatively.
Topics: Analgesics, Opioid; Animals; Butorphanol; Dogs; Female; Hysterectomy; Morphine; Nalbuphine; Ovariectomy; Pain, Postoperative; Prospective Studies; Single-Blind Method
PubMed: 32891492
DOI: 10.1016/j.vaa.2020.07.035 -
Veterinary Anaesthesia and Analgesia Jan 2018To compare sedation and effects on heart rate (HR), mean arterial pressure (MAP) and respiratory rate (f) of nalbuphine and butorphanol, alone or combined with... (Comparative Study)
Comparative Study Randomized Controlled Trial
OBJECTIVE
To compare sedation and effects on heart rate (HR), mean arterial pressure (MAP) and respiratory rate (f) of nalbuphine and butorphanol, alone or combined with acepromazine in dogs.
STUDY DESIGN
Prospective, randomized experimental trial.
ANIMALS
Eight healthy Beagle dogs, aged (mean ± standard deviation) 3.4 ± 0.5 years and weighing 11.0 ± 1.3 kg.
METHODS
Each dog was treated four times: physiological saline (1 mL) combined with nalbuphine (0.5 mg kg; SAL-NAL) or butorphanol (0.15 mg kg; SAL-BUT), and acepromazine (0.05 mg kg) combined with nalbuphine (0.5 mg kg; ACP-NAL) or butorphanol (0.15 mg kg; ACP-BUT), intravenously (IV). The degree of sedation, assessed by a numeric descriptive scale (NDS) and simple numerical scale (SNS), HR, MAP, f and rectal temperature (RT), were recorded before and 20 minutes after administration of saline or acepromazine, then 15, 30, 60, 90 and 120 minutes after nalbuphine or butorphanol. Values were compared with baseline and among treatments.
RESULTS
Mild sedation was recorded for SAL-NAL and SAL-BUT, and moderate sedation for ACP-NAL and ACP-BUT. NDS and SNS scores were higher for SAL-BUT and ACP-BUT at some time points when compared with SAL-NAL and ACP-NAL, respectively (p < 0.001). HR was lower in ACP-NAL than in ACP-BUT at 120 minutes and f was lower in SAL-BUT than in SAL-NAL at 30 and 120 minutes (p < 0.05). RT was lower in SAL-BUT (37.5 ± 0.5 °C) compared with SAL-NAL (38.0 ± 0.5 °C) at 60-120 minutes (p < 0.05).
CONCLUSIONS AND CLINICAL RELEVANCE
Butorphanol promoted a higher sedative effect than nalbuphine when alone and combined with acepromazine. IV administration of nalbuphine or butorphanol, with or without acepromazine, at the doses studied, resulted in minimal decreases in MAP, HR, f and RT.
Topics: Acepromazine; Anesthetics, Combined; Animals; Blood Pressure; Body Temperature; Butorphanol; Deep Sedation; Dogs; Female; Heart Rate; Hypnotics and Sedatives; Male; Nalbuphine; Prospective Studies; Respiratory Rate
PubMed: 29183660
DOI: 10.1016/j.vaa.2017.08.003 -
Veterinary World Mar 2022The use of anesthetic infusions based on pharmacokinetic values associated with anesthetic plan and bispectral index in dogs have not been well-documented in the...
BACKGROUND AND AIM
The use of anesthetic infusions based on pharmacokinetic values associated with anesthetic plan and bispectral index in dogs have not been well-documented in the literature. This study aimed to evaluate the bispectral index (BIS) change based on pre-propofol and establish clinical anesthetic depth changes during propofol sequential target-controlled infusion (STCI) in dogs with a plasma target of 5 μg/mL.
MATERIALS AND METHODS
Twenty healthy male dogs aged 1-3 years and weighing 9.8-44 kg were recruited. These dogs were pre-medicated intramuscularly with methadone (0.2 mg/kg) and acepromazine (0.03 mg/kg). After 30 min, propofol anesthetic induction and maintenance were initiated using STCI according to dog pharmacokinetic (PK) parameters. Subsequently, the target plasma concentration of propofol was set at 5 μg/mL for both anesthetic induction and the 120 min maintenance. Then, TivaTrainer v.9.1 software was used to calculate anesthetic infusion rates in a TCI plasmatic concentration mode using the PKs model optimized by covariates for propofol TCI in dogs. The BIS value was recorded every 5 min from the beginning of induction until the end of anesthesia. Finally, analysis of variance was performed on numerical data using the Friedman test, followed by the Bonferroni adjustment (p<0.05).
RESULTS
A statistical difference was observed between the baseline BIS value (T0), with a median value of 84.5 (81-97), and BIS after every 15 min (T15) of inducing anesthesia. Surgical anesthetic depth was also reached in 18 of 20 dogs after 10 min of infusion and in all dogs after 20 min, with a median BIS value of 72 (53-89) at the time of surgical anesthesia depth. Results also showed no BIS variation (p<0.05) between anesthetic moments after anesthetic induction with a substantial amplitude of BIS in the surgical anesthetic depth. Moreover, the maximum depth of anesthesia in all dogs by clinical evaluation was reached after 20 min of anesthesia and then remained stable throughout the anesthetic period.
CONCLUSION
This study suggested that most dogs (90%) attained a surgical depth of anesthesia within 15 min of STCI onset, with a plasma target of 5 μg/mL and no change in anesthetic depth throughout the period anesthesia lasted. Furthermore, median BIS values remained high even after dogs reached the surgical depth of anesthesia, indicating that the comparison of BIS values of dogs and humans should not be considered for classifying anesthetic and hypnotic depths in dogs.
PubMed: 35497961
DOI: 10.14202/vetworld.2022.537-542 -
Veterinary Anaesthesia and Analgesia Jul 2022To determine changes in distribution of lung ventilation with increasing intra-abdominal pressure (IAP) from carbon dioxide (CO) insufflation in standing sedated horses.
OBJECTIVE
To determine changes in distribution of lung ventilation with increasing intra-abdominal pressure (IAP) from carbon dioxide (CO) insufflation in standing sedated horses.
STUDY DESIGN
Prospective experimental study.
ANIMALS
A group of six healthy adult horses.
METHODS
Each horse was sedated with acepromazine, detomidine and butorphanol and sedation maintained with a detomidine infusion. The horse was restrained in a stocks system and a 32 electrode electrical impedance tomography (EIT) belt was wrapped around the thorax at the fifth-sixth intercostal space. EIT images and arterial blood samples for PaO and PaCO, pH and lactate concentration were obtained during capnoperitoneum at 0 (baseline A), 5, 8 and 12 mmHg as IAP increased and at 8, 5, 0 (baseline B) mmHg as IAP decreased. At each IAP, after a 2 minute stabilization period, EIT images were recorded for ≥ 2 minutes to obtain five consecutive breaths. Statistical analysis was performed using anova for repeated measures with Geisser-Greenhouse correction and a Tukey's multiple comparison test for parametric data. The relationship between PaO and the center of ventilation in the ventral-dorsal (CoV-VD) and right-left (CoV-RL) directions or total impedance change as a surrogate for tidal volume (ΔZV) were tested using linear regression analysis. Significance was assumed when p ≤ 0.05.
RESULTS
There were no significant changes in CoV-VD, CoV-RL, PaO, PaCO, lactate concentration, pH, heart rate and respiratory rate with targeted IAP. There was a significant decrease in ΔZV compared with baseline A at 5 mmHg IAP as IAP was increased.
CONCLUSIONS AND CLINICAL RELEVANCE
Capnoperitoneum causes a significant decrease in ΔZV in standing sedated horses with increasing IAP.
Topics: Animals; Electric Impedance; Horses; Lactates; Lung; Prospective Studies; Respiration; Tomography, X-Ray Computed
PubMed: 35641422
DOI: 10.1016/j.vaa.2022.04.004 -
Research in Veterinary Science Mar 2021Low arterial oxygen is a common complication in anesthetized horses and placing the animal in reverse Trendelenburg (RT) position may treat hypoxemia. The objective of...
Low arterial oxygen is a common complication in anesthetized horses and placing the animal in reverse Trendelenburg (RT) position may treat hypoxemia. The objective of this study was to assess the arterial partial pressure of oxygen (PaO) in horses placed in a 5-degree RT compared to horizontal (H) position. Client-owned healthy horses (n = 60) undergoing elective surgeries were enrolled in a randomized controlled clinical study. Horses were sedated with butorphanol, an α-adrenoceptor agonist, ± acepromazine and induced with ketamine combined with a benzodiazepine, propofol, or guaifenesin. Anesthesia was maintained with isoflurane in oxygen with mechanical ventilation. Each group (RT and H) included 30 horses, 10 in each recumbency (dorsal, right and left lateral). Arterial blood gas analyses (aBG) were performed following arterial catheter placement then hourly. Time first-to-last aBG, changes in PaO, dynamic compliance (C), estimated pulmonary shunt fraction (F-shunt), and alveolar dead space to tidal volume ratio (V/V) were evaluated with a 2-way analysis of variance. Statistical significance was set at p < .05. Overall, PaO increased in all groups; however no significant difference was found between recumbencies (dorsal, right and left lateral) and RT versus H in changes over time for PaO (p = .064 and p = .070, respectively), C (p = .721 and p = .672, respectively), F-shunt (p = .055 and p = .054, respectively), or V/V (p = .616 and p = .064, respectively). In healthy anesthetized horses, 5-degree RT did not affect changes in PaO as compared to H position.
Topics: Anesthesia; Animals; Blood Gas Analysis; Female; Head-Down Tilt; Horses; Isoflurane; Ketamine; Male; Oxygen; Partial Pressure; Pilot Projects; Propofol; Prospective Studies; Respiration, Artificial
PubMed: 33066990
DOI: 10.1016/j.rvsc.2020.10.005 -
Journal of Equine Veterinary Science Mar 2020The aim of this study was to compare the effects of methadone combined with detomidine or acepromazine on the quality of sedation and its influence over dissociative...
The aim of this study was to compare the effects of methadone combined with detomidine or acepromazine on the quality of sedation and its influence over dissociative anesthesia in healthy horses. In a crossover design, seven horses were administered with 0.1 mg/kg methadone and 0.02 mg/kg detomidine intravenously (group MD) or 0.1 mg/kg methadone and 0.05 mg/kg acepromazine intravenously (group MA). Subsequently, anesthesia was induced with a combination of 2.2 mg/kg ketamine and 0.1 mg/kg midazolam intravenously. Descriptive scales and footages were used to evaluate the quality of sedation, induction, anesthesia maintenance, and recovery. Physiological parameters, arterial blood gas, and electrolytes were assessed from baseline to the recovery of anesthesia. The MA group showed lower arterial blood pressure and higher heart rate compared with the group MD. A slight decrease in arterial blood oxygen levels was observed after recumbency, more prominently in the MA group. There was no difference in the quality or time of induction or maintenance or recovery of anesthesia between groups. The results suggest that both premedication protocols produce good sedation and quality of anesthesia. Methadone combined with detomidine produced a good cardiopulmonary stability compared with methadone combined with acepromazine and might be safer to be used as premedication for dissociative anesthesia compared with methadone combined with acepromazine in healthy horses.
Topics: Acepromazine; Anesthesia, General; Animals; Horses; Imidazoles; Methadone
PubMed: 32067671
DOI: 10.1016/j.jevs.2019.102908 -
The Journal of Physiology Jun 2019Contractility of lymphatic collectors is essential for the functionality of the lymphatic system and, thus, for lymph flow. Previously published rates of lymphatic...
KEY POINTS
Contractility of lymphatic collectors is essential for the functionality of the lymphatic system and, thus, for lymph flow. Previously published rates of lymphatic collectors in mice vary from 1.1 to 17 contractions/min with little agreement between investigators. In this study, we focused on the effects of different anaesthesia regimens on lymphatic vessel contractility using in vivo imaging approaches. We show that isoflurane and pentobarbital have an inhibitory effect on lymphatic contractility compared to mice under other anaesthesia regimens and in awake conditions. These results should help to establish a standardization of lymphatic contraction studies in mice and may also have relevance for patients undergoing anaesthesia during surgery.
ABSTRACT
Contractions of collecting lymphatic vessels are essential for the function of the lymphatic vascular system, due to the lack of a central pump to drive flow. A wide range of physiological contraction frequencies and strengths have been reported in previous in vivo studies in mice. This is probably due to the different types of anaesthesia that have been used and which might have exerted direct influences on lymphatic vessel function. We investigated six commonly used anaesthesia regimens for their influence on lymphatic vessel contractility using near-infrared in vivo imaging approaches. Non-invasive imaging of the lymphatic leg collector revealed distinct effects of the anaesthesia regimens with reduced contraction activity under isoflurane and pentobarbital anaesthesia. Isoflurane also reduced the contractility of near-infrared dye-loaded vessels during invasive imaging of the lymphatic flank collector whereas the combination of ketamine/xylazine/acepromazine had no major effects. The transport time of a lymphatic-specific dye from the skin through the lymphatic vasculature to the systemic bloodstream was also delayed under isoflurane anaesthesia. Based on these results, we recommend use of combinations of ketamine and medetomidine for future non-invasive studies and of ketamine, xylazine and acepromazine for invasive studies. Beyond their importance for facilitating the interpretation and planning of animal studies, our findings might also have relevance for human patients undergoing anaesthesia for surgical procedures.
Topics: Anesthesia; Anesthetics, Inhalation; Animals; Female; Isoflurane; Ketamine; Lymphatic Vessels; Medetomidine; Mice, Transgenic; Pentobarbital; Xylazine
PubMed: 30829392
DOI: 10.1113/JP277254 -
PloS One 2021Although facial characteristics are used to estimate horse sedation, there are no studies measuring their reliability and validity. This randomised controlled,...
Although facial characteristics are used to estimate horse sedation, there are no studies measuring their reliability and validity. This randomised controlled, prospective, horizontal study aimed to validate a facial sedation scale for horses (FaceSed). Seven horses received detomidine infusion i.v. in low or high doses/rates alone (DL 2.5 μg/kg+6.25 μg/kg/h; DH 5 μg/kg+12.5 μg/kg/h) or combined with methadone (DLM and DHM, 0.2 mg/kg+0.05 mg/kg/h) for 120 min, or acepromazine boli i.v. in low (ACPL 0.02 mg/kg) or high doses (ACPH 0.09 mg/kg). Horses' faces were photographed at i) baseline, ii) peak, iii) intermediate, and iv) end of sedation. After randomisation of moments and treatments, photos were sent to four evaluators to assess the FaceSed items (ear position, orbital opening, relaxation of the lower and upper lip) twice, within a one-month interval. The intraclass correlation coefficient of intra- and interobserver reliability of FaceSed scores were good to very good (0.74-0.94) and moderate to very good (0.57-0.87), respectively. Criterion validity based on Spearman correlation between the FaceSed versus the numerical rating scale and head height above the ground were 0.92 and -0.75, respectively. All items and the FaceSed total score showed responsiveness (construct validity). According to the principal component analysis all FaceSed items had load factors >0.50 at the first dimension. The high internal consistency (Cronbach´s α = 0.83) indicated good intercorrelation among items. Item-total Spearman correlation was adequate (rho 0.3-0.73), indicating homogeneity of the scale. All items showed sensitivity (0.82-0.97) to detect sedation, however only orbital opening (0.79) and upper lip relaxation (0.82) were specific to detect absence of sedation. The limitations were that the facial expression was performed using photos, which do not represent the facial movement and the horses were docile, which may have reduced specificity. The FaceSed is a valid and reliable tool to assess tranquilisation and sedation in horses.
Topics: Anesthesia; Animals; Horses; Male
PubMed: 34061878
DOI: 10.1371/journal.pone.0251909