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. 2024 Apr;65(4):351–358.

Comparison of sedation with dexmedetomidine administered subcutaneously at 2 different locations on the head in dogs

Marie Llido 1, Claire Leriquier 1, Tristan Juette 1, Javier Benito 1, Mila Freire 1,✉
PMCID: PMC10945449  PMID: 38562980

Abstract

Objective

This study aimed to compare the sedative effects of dexmedetomidine administered to dogs subcutaneously (SC) at the Governing Vessel 20 (GV20) acupuncture point and at another point on the head.

Animals and procedure

Ten client-owned dogs were included. Dogs were sedated 2 times, 14 d apart, with 200 μg/m2 of dexmedetomidine, SC, at GV20 and at a point at the base of the ear (SC-head). The sedation was assessed with a sedation scale and a Dynamic and Interactive Visual Analogue Scale (DIVAS). The ease of performing radiographic studies, physiological parameters, and adverse events were recorded. Statistical linear mixed-effect models (ANOVA) were applied. Statistical significance was set at P < 0.05.

Results

The time to sedation and sedation scores were similar for both groups. The level of sedation achieved was adequate to perform orthopedic radiographs for 9/10 (90%) cases in the GV20 group and 8/10 (80%) cases in the SC-head group. Heart and respiratory rates decreased significantly over time in both groups (P < 0.001). Adverse events were infrequent and self-limiting.

Conclusion

Our study provides evidence that SC administration of dexmedetomidine on the head, at the GV20 point or at the base of the ear, is easy and provides a sufficient level of sedation to obtain orthopedic radiographs in dogs.

Introduction

Dogs brought to a surgery service frequently require radiographic examinations, which must be performed with safety, efficacy, and speed. Dexmedetomidine, an α2-adrenergic receptor agonist, is commonly used because of its profound sedative effect and reversibility with the administration of atipamezole. The administration routes commonly used for sedative drugs are intravenous (IV), intramuscular (IM), transmucosal, and intranasal (1–5). More recently, with an increasing interest in alternative medicine, subcutaneous (SC) drug administration at acupuncture points has been described (6,7). Two acupuncture points have been of particular interest for sedation in dogs and have been studied more extensively. These are the Governing Vessel 20 (GV20) acupuncture point, located on the dorsal midline of the skull (8–12); and the Yintang acupuncture point, located midway between the medial ends of the 2 eye-brows (7,9,13,14).

A previous study with beagles showed an increased effect of dexmedetomidine administered at the GV20 acupuncture point compared to IM administration (12). A more recent publication, also in dogs, demonstrated better postoperative pain management with 1/10 of the dose of hydromorphone administered at the GV20 point compared to the higher dose administered IM (15). This route of administration was also investigated in birds, in which 1/2 of the dose of ketamine-midazolam administered at the GV20 point provided similar sedation to the full dose administered IM (16). Our research group recently showed that dexmedetomidine administration at the GV20 point provides an effective level of sedation to perform orthopedic radiographic examinations in dogs in the clinical setting (17). The sedation level achieved was clinically similar to that with IV administration and was greater and faster than with the IM route. However, the sedative effect of dexmedetomidine administered SC at any other location on the head not associated with acupuncture points of relaxation was not investigated. Consequently, it is unknown whether the sedative effects would be equal regardless of the point of injection on the head.

The objective of this study was to compare the sedative effects of dexmedetomidine administered SC at the GV20 acupuncture point and at a different point on the head of dogs in a clinical setting. We hypothesized that dexmedetomidine administered SC at the GV20 point would provide better-quality and faster sedation than the same dose of dexmedetomidine administered SC at a different location on the head in healthy dogs.

Materials and methods

This prospective, crossover, randomized, blinded, controlled clinical study was approved by the local Institutional Animal Care and Use Committee (IACUC-CÉUA 20-Rech-1996) of the University of Montreal (Saint-Hyacinthe, Quebec). Informed consent was obtained from the owner of each dog before enrollment. This study adhered to the Animal Research: Reporting of In Vivo Experiments (ARRIVE) guidelines (18).

Animals

This study included 10 client-owned dogs presented to the Small Animal Surgery Service (University of Montreal) that required orthopedic and radiographic examinations. Inclusion criteria were being healthy apart from the orthopedic condition, having a body weight > 8 kg, and having fasted for a minimum of 6 h. Dogs were considered healthy based on their medical history, physical examination, and blood work [complete blood (cell) count and chemistry panel] completed within 3 mo before participation in the study. Dogs were excluded if they showed clinical signs other than orthopedic conditions and/or aggressive behaviors during manipulation. None of the dogs was receiving analgesics at the time of inclusion in the study.

Study design

The enrolled dogs were placed in a quiet, dim room to acclimate to the environment for 15 min. Each dog was sedated twice, 2 wk apart, with 200 μg/m2 of dexmedetomidine (Dexdomitor; Zoetis, Kirkland, Quebec) injected SC into a different location each time: i) at the GV20 acupuncture point (GV20 group) and ii) at another point on the head, at the base of the ear (left or right, determined randomly) and not associated with acupuncture points of relaxation/sedation (SC-head group). The dose used was determined based on a previous study that demonstrated its effectiveness in sedating dogs when injected SC at the GV20 acupuncture point (17). The order of the sedation protocol for each dog (GV20 or SC-head) was determined randomly. Drug injections were always performed by the same person (CL) with experience administering drugs at the GV20 acupuncture point. The GV20 acupuncture point is located on the dorsal midline of the skull, intersecting the coronal line from both sides of the rostral ear base, at the rostral end of the external sagittal crest (11) (Figure 1 A, B). The injections at the other point were done at the rostral aspect of the base of the left or right ear (Figure 1 C).

Figure 1.

Figure 1

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Location of the different subcutaneous injection sites in this canine study. A — Governing Vessel 20 (GV20) acupuncture point on a canine skull. B and C — Subcutaneous injections in a dog at the GV20 point (B) and at the base of the ear (C).

Following dexmedetomidine administration, the level of sedation was evaluated every 5 min for a total of 30 min. Each animal was then transported on a gurney to the radiology room with an anesthesia hood covering its head to reduce stimuli during transport. The radiographic examinations consisted of 2 standardized orthogonal radiographs (e.g., lateral and ventrodorsal views of the pelvis) taken while using sandbags to restrain the dog. The lateral radiographic view was always taken first. The ease of positioning the dog for the radiographs was scored using a Dynamic and Interactive Visual Analogue Scale (DIVAS) by one person (CL) who was not blinded to the location of the injection. The dog was finally transported back to the initial room for recovery. All animals were antagonized with 2000 μg/m2 of atipamezole (Antisedan; Zoetis) injected IM into the lumbar epaxial muscles. Any adverse events that occurred at any time during the study and the first 24 h after discharge were recorded.

Although animals were sedated twice, radiographic examinations were completed only once (only those radiographs deemed necessary because of clinical signs and findings on the orthopedic examination). Even when radiographs were not taken during one of the sedation episodes, animals were still transported to the radiology room on the gurney and positioned on the radiology table as if radiographs were going to be taken (lateral and ventrodorsal views of the pelvis).

Following statistical analysis and in light of unexpected findings (i.e., rejection of the hypothesis), we sedated 8 of the included dogs with 200 μg/m2 dexmedetomidine injected SC in the interscapular region. The levels of sedation, radiographic examinations, physiological parameters, and adverse events were recorded as detailed above. However, evaluations were neither blinded nor randomized. The data obtained from this sedation episode and its comparison with the 2 groups of SC injections on the head are provided; however, the findings should be interpreted with caution as the interscapular injection was not part of the initial study design.

Assessment and data collection

The level of sedation was blindly assessed by the same person (ML), with a validated sedation scale (19–21) and DIVAS (12), every 5 min for 30 min. The sedation scale consisted of 7 items that were assessed in the same order each time and ranked from 0 to 2, 3, or 4, depending on the item: general appearance/ attitude, spontaneous posture, reaction to noise (clicker-actuated at ~150 cm from the head), eye position, palpebral reflex, jaw and tongue relaxation, and resistance when placed in lateral recumbency (see Table S1, available online from: www.canadianveterinarians.net). Scores for each item were summed to obtain a total score (range: 0 to 21). Three previously defined levels of sedation were used for data analysis: little/no sedation, score 0 to 2; moderate sedation, score 4 to 11; heavy sedation, score ≥ 13; with score 3 = little-to-moderate sedation and 12 = moderate-to-heavy sedation (19). Finally, for each DIVAS assessment, a mark was made on a 100-millimeter line, with the left end (0 mm) corresponding to “no sedation” and the right end (100 mm) corresponding to “best sedation possible” (22).

The following physiological variables were monitored throughout the procedure, from before drug administration until injection of atipamezole: heart rate (HR) and respiratory rate (RR) every 5 min and rectal temperature (RT) every 15 min. The time elapsed from dexmedetomidine administration until the level of sedation was considered appropriate to perform the radiographic examination was recorded (this was judged subjectively; dogs could be placed in lateral recumbency with limited reaction to stimuli). Evaluation of the level of sedation and physiological variables continued for 30 min for all animals, independent of when the level of sedation was deemed subjectively appropriate to perform the radiographs.

Statistical analysis

Due to the lack of objective data for dogs regarding the SC use of dexmedetomidine, the number of dogs required was estimated using a power calculation (www.sealedenvelope.com) with the results from the sedation episodes of the first 5 dogs. A minimum of 7 dogs was required to achieve 80% power to detect a difference of 60% in sedative scores between the GV20 and SC-head groups, with an alpha-level of 0.05. Each dog was its own control. Numerical data were tested for normality with the Shapiro-Wilk test. Results of parametric tests are shown as mean (± standard deviation) and results of non-parametric tests as median (min, max). Data (sedation scale and DIVAS scores, the time elapsed until adequate sedation was achieved, radiographic sedation DIVAS score, HR, RR, and RT) were tested using linear mixed-effect models — that is, Type-III analysis of variance (ANOVA) with the Satterthwaite method (R software, package lmerTest) (23); with group, age, sex, and weight as fixed effects and subject ID as random effect. Logarithmic transformation or arcsine square-root transformation (for scores with an upper limit) were used to normalize distributions when needed before testing. Tukey post-hoc comparisons were used to define which group(s) differed from the others, using the P-values adjusted for multiple comparisons. Time comparisons were made for sedation scores and DIVAS scores at each time point in relation to T5 (5 min after dexmedetomidine administration) and T0 (before dexmedetomidine administration) for physiological variables (HR, RR, and TR). Statistical significance was set at P < 0.05. Statistical analyses were conducted using standard statistical software (R version 4.0.3; R Foundation for Statistical Computing, Vienna, Austria; and GraphPad Prism version 8.1 for Windows; GraphPad Software, San Diego, California, USA).

Results

Ten dogs were enrolled in the study. The breeds represented were the goldendoodle, boxer, bullmastiff, pit bull, English setter, Belgian Tervuren, Siberian husky, Australian shepherd, fox terrier, and a mixed-breed dog. There were 7 spayed females and 3 neutered males with a median age of 6.43 y (range: 1.20 to 14.69 y) and median weight of 21.5 kg (range: 8.6 to 34.5 kg).

Sedation

The median time elapsed from drug administration until the level of sedation was considered appropriate to perform radiographic examinations was 12.5 min (range: 10 to 20 min) in the GV20 group and 10 min (range: 5 to 20 min) in the SC-head group. The time to sedation was not significantly different between groups (P = 0.30). Significant negative effects on the time to sedation of weight (P = 0.024) and age (P = 0.002) were identified (time to sedation decreased in heavier and older dogs).

The sedation scale (Figure 2 A) and DIVAS (Figure 2 B) scores increased significantly over time (P < 0.001), and no significant differences were identified between the GV20 and SC-head groups at any time point during the 30-minute observation period (P > 0.05). Sedation scale and DIVAS scores did not vary as functions of weight and sex but increased significantly with age (P = 0.027 and P = 0.016, respectively). The mean values of the sedation scale corresponding to a deep level of sedation (score > 13) were first achieved at 15 min in the GV20 group and at 10 min in the SC-head group (Figure 2 A).

Figure 2.

Figure 2

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Graphs representing sedation scale (A) and Dynamic and Interactive Visual Analogue Scale (DIVAS) (B) mean scores for the 2 groups (n = 10) during the 30-minute observation period. Symbols (circle, square) represent the means and bars represent the standard deviations. Cutoff lines in (A) separate the 3 different levels of sedation (little/no, moderate, heavy) as described by Wagner et al (2017) (19). The sedation scale and DIVAS scores increased significantly over time (P < 0.001), and no significant differences were identified between the groups at any time point. The “*” symbol represents a P < 0.001 of sedation scale and DIVAS scores at each time point compared to T5 (5 min after dexmedetomidine administration) for both groups.

The mean HR and RR decreased significantly over time in both groups (P < 0.001). The HR and RR were significantly higher in the GV20 group compared to the SC-head group (P = 0.036 and P = 0.002, respectively) (Figure 3). The mean HR and RR did not vary as functions of weight, sex, or age. The mean RT decreased progressively over time, becoming significantly different between 15 and 30 min (P = 0.039). No significant differences were observed between groups (P = 0.46), but a significant negative effect of age (P < 0.001) was identified.

Figure 3.

Figure 3

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Graphs representing the mean heart rates (HR; A) and respiratory rates (RR; B) for the 2 groups (n = 10) during the 30-minute observation period. Symbols (circle, square) represent the means and bars represent the standard deviations. The mean HR (A) and RR (B) decreased significantly over time in both groups (P < 0.001). The HR and RR were significantly higher in the GV20 group compared to the SC-head group (P = 0.036 and P = 0.002, respectively). The “*” symbol in (A) represents a P < 0.001 of HR at each time point compared to T0 (before dexmedetomidine administration) for both groups. No significant differences were identified in RR at any time point compared to T0 for both groups.

Orthopedic radiographic examinations

The sedation level achieved was adequate to perform 2 orthogonal radiographs in 9 out of 10 cases (90%) in the GV20 group, and in 8 out of 10 cases (80%) in the SC-head group. In the dog for which the ventrodorsal view of the pelvis could not be obtained with the GV20 sedation protocol, neither of the radiographic views (ventrodorsal or lateral) was feasible with the SC-head protocol. The radiographic DIVAS scores for lateral and ventrodorsal projections were not different between groups (P = 0.20 and P = 0.25, respectively), and they did not vary as functions of weight or sex, but there was a significant positive effect of age for the lateral radiographic projection (P = 0.015).

Adverse events

Minor adverse events were reported in 7 dogs: 3 in the GV20 group and 4 in the SC-head group. Two dogs experienced 2 different types of adverse events. The most common adverse events were muscle tremors and transitory apnea (cessation of spontaneous respiration for ≥ 20 s), with each of them reported in 3 dogs. Transitory apnea was only reported in the SC-head group. Gastrointestinal signs were also reported in 2 dogs in the GV20 group, with 1 experiencing hypersalivation and the other vomiting. One dog in the SC-head group experienced hyperthermia, defined as RT ≥ 39.8°C, during the sedation period (RT returned to normal values during recovery). No adverse events were reported during recovery, following atipamezole administration, or within the first 24 h following discharge.

Sedation with interscapular subcutaneous dexmedetomidine

In the light of unexpected findings after injection of dexmedetomidine SC on the head, 8 of the dogs were sedated a 3rd time, with 200 μg/m2 dexmedetomidine injected SC in the interscapular region. As indicated, this sedation episode was not evaluated as a 3rd study group because it was neither randomized nor evaluated with blinding. However, the results merit mention because of the important differences compared to SC administration on the head. The time elapsed from drug administration until the level of sedation was considered appropriate to obtain radiographs reached the 30-minute mark in 6 out of 8 dogs. For these animals, the level of sedation achieved was not considered appropriate to complete radiographic studies at the end of the evaluation period (they walked to the radiology room as their transport on the gurney was considered dangerous, and positioning on the radiology table was impossible). Although direct comparisons cannot be done with the 2 groups in this study and results should be interpreted with caution, the time to sedation was significantly longer than in the GV20 and SC-head groups (P < 0.001). The sedation scale and DIVAS scores increased significantly over time (P < 0.001), but they were significantly lower for interscapular administration than in the GV20 and SC-head groups (P < 0.001), except 5 min after dexmedetomidine administration, when sedation scores were similar to those in the GV20 group. The maximum sedation scale and DIVAS scores, which corresponded to a mild level of sedation, were observed at the 30-minute mark (see Table S2, available online from: www.canadianveterinarians.net). As in the GV20 and SC-head groups, the mean HR and RR decreased significantly over time (P < 0.001). However, the RR was significantly higher at all time points than in the GV20 and SC-head groups (P = 0.032 and P = 0.014, respectively). The level of sedation achieved was adequate to obtain 2 orthogonal radiographs in only 2 dogs (25%). The radiographic DIVAS scores for lateral and ventrodorsal projections were significantly lower in the GV20 (P = 0.002, lateral view; P < 0.001, ventrodorsal view) and SC-head (P = 0.01, lateral view; P = 0.001, ventrodorsal view) groups. No adverse events were reported in dogs after SC dexmedetomidine administration in the interscapular region.

Discussion

The results of this study reject the hypothesis that dexmedetomidine administered SC at GV20 point provides better-quality and faster sedation than the same dose of dexmedetomidine administered SC at another point on the head in healthy dogs. Both sedation protocols had similar times to sedation and provided a level of sedation that allowed most dogs to undergo orthopedic radiographic studies. Although SC administration of dexmedetomidine at equal doses in the interscapular region does not seem to provide an adequate level of sedation to conduct radiographic studies, this information should be regarded with caution as this protocol was not evaluated with blinding or randomization.

The level of sedation achieved was sufficient to conduct orthopedic radiographs in most dogs in the GV20 (90%) and SC-head (80%) groups. Our research group has compared the sedation achieved after dexmedetomidine administration at the GV20 point with the IM and IV routes (17). The degree of sedation with GV20 administration was clinically comparable to that achieved with IV administration, and both routes provided a greater level of sedation than the IM route. The results of the present study suggest that the sedative effects after administration of dexmedetomidine at the GV20 acupuncture point are mostly related to the route of administration (SC) on the head and not to the acupuncture point. However, the study design did not allow determination of the degree of sedation/relaxation obtained due to stimulation of the acupuncture point itself. To answer the question of whether the sedative effects were partially due to or increased by acupuncture point stimulation, an acupuncture group with sham treatment and a non-acupuncture control group will need to be evaluated with blinding.

Both GV20 and SC-head administrations achieved the desired clinical effect. Therefore, administration at the exact location of the acupuncture point on the head might not be essential to achieve the desired drug effect. Both the stimulation of the GV20 point and dexmedetomidine have been suggested to inhibit the neurons of the locus coeruleus nucleus in the brain stem (9,24). If stimulation of the GV20 point alone had any sedative effect in the dogs in our study, it might have been hidden by the sedative effect of dexmedetomidine, since the sedation level achieved was similar to that in the SC-head group. The point of injection at the base of the ear was selected with the intention of locating it in an area where there are no acupuncture points associated with relaxation/sedation. Many acupuncture points are present on the head in dogs, and even if they are not located at the selected point of injection, they are in close proximity, and many of those points are related to trigeminal and vagal innervation. Stimulation of these points may send inputs to the nucleus tractus solitarius and thus to the rostral ventrolateral medulla, resulting in autonomic effects with downregulation of the sympathetic nervous system. These effects could have contributed to the lack of difference observed in the level of sedation between the GV20 and SC-head groups.

Although evaluation of sedative effects after dexmedetomidine administration in the interscapular region was not part of the initial experimental design, and thus this group of animals could not be included as a 3rd study group, most of these dogs walked to the radiology room because their levels of sedation were very low and inadequate for obtaining radiographs. When the data for interscapular administration were compared with those for the 2 study groups, SC administration on the head, regardless of the location, provided superior sedative effects. However, a prospective, blinded, and randomized study including the interscapular injection as a 3rd group will be necessary to test this hypothesis. If these differences were confirmed with the appropriate study design, it would be reasonable to suggest that SC administration on the head results in better absorption of dexmedetomidine when compared to SC administration in the interscapular region. Further investigations would be needed to determine if this could be due to higher blood flow in the SC tissue on the head, the presence of interscutularis muscle, or the differing amounts of SC adipose tissue in these 2 locations.

The radiographic DIVAS scores (ease of conducting the radiographic examinations) for lateral and ventrodorsal projections were similar for the GV20 and SC-head groups, which is consistent with the similar levels of sedation achieved. The pelvic ventrodorsal projection required a greater degree of relaxation and was more discriminant to differentiate an adequate sedation level.

Although the doses used in this study were lower than those recommended on the product label for IV and IM routes (i.e., 375 μg/m2 and 500 μg/m2, IV and IM, respectively), in both the GV20 and SC-head groups, a heavy level of sedation (based on the sedation scale and DIVAS scores) was achieved 20 to 25 min after dexmedetomidine administration. The mean times elapsed from drug administration until the sedation was considered appropriate to obtain the radiographs were 12.5 and 10 min in the GV20 and SC-head groups, respectively — an acceptable onset of action in the clinical setting. It is possible that an adequate level of sedation would have been achieved with a lower dose in these 2 groups. In a recent study, Scallan et al (15) were able to obtain adequate control of postoperative pain following canine ovariohysterectomy with a low dose of hydromorphone (0.01 mg/kg) administered at the GV20 point. On the other hand, for 6 out of 8 dogs injected in the interscapular region, the sedation level achieved at the 30-minute mark was not sufficient to perform radiographic examinations; whether a higher level of sedation would have been achieved later in these dogs is unknown.

Following injection of dexmedetomidine, the HR and RR values decreased as expected (20,25,26). These results are similar to those of a previous report by Pons et al (12), where deeper levels of sedation were achieved with administration of dexmedetomidine at the GV20 point than with the IM route, and HR was significantly lower in the GV20 group. Results are also similar to those of a study done by our research group, where both HR and RR were significantly lower in the GV20 group than in the IM group (17). Whether the deeper levels of sedation and greater depression of HR and RR achieved when dexmedetomidine is administered SC on the head respond to a more profound vascularization at this location will need to be investigated. Studies on the pharmacokinetics and pharmacodynamics of dexmedetomidine administration at the GV20 acupuncture point are lacking.

The most common adverse events in this study were muscle tremors and transitory apnea, previously reported with the administration of dexmedetomidine and medetomidine (25,26). Transient apnea was seen only in the SC-head group, with a breathing pattern characterized by clusters of breaths followed by a short period of apnea. This peculiar pattern has been reported with the use of dexmedetomidine IV in healthy beagles (27). Other reported adverse events of α2-agonists are gastrointestinal (28); these were observed in 2 dogs in the GV20 group (vomiting and ptyalism). The proportion of animals that exhibited this adverse event was lower than that reported by Pons et al (12) (33% of dogs vomited after administration of 125 μg/m2 at the GV20 point). Although they suggested the incidence of this adverse event might be associated with the dose administered, the results of the present study do not support a positive relationship between dose and incidence of vomiting. On the contrary, our results seem to agree with those published by the FDA (29) and Zoetis (30) regarding incidence of vomiting and dose of dexmedetomidine, where higher doses were associated with lower incidences of vomiting. Overall, the proportion of animals that developed adverse events after SC administration of dexmedetomidine was low, and the signs were mild and transient.

Our impression is that the administration of sedatives SC on the head offers several advantages over more conventional routes such as IV and IM. First, the SC route is easy, fast, and requires a lower level of training and expertise. This is especially important in teaching environments where students participate in drug administration during training. It is also of interest in clinics where many animals are evaluated daily, because it decreases the time required to administer the sedatives compared to the IV route. Second, SC administration seems to cause less discomfort than IV or IM injections (reactions to injections were minimal when present) and it requires less restraint of the animals, thus reducing stress. We have successfully used this route of administration in animals showing aggressive behaviors for which IV administration would have been very difficult or required a high level of restraint, contributing to stress to the animal and risk for staff members.

The present study had several limitations. First, the DIVAS scale used to grade the degree of sedation and ease of positioning the dogs for the radiographic examinations is not a validated scale, and the variability in results might explain the lack of differences between the GV20 and SC-head groups. Large variability was present in the results of the radiographic DIVAS even though it was evaluated by a single observer. In addition, the observer completing the radiographic DIVAS scale was not blinded to the treatment group, which might have biased the results. The use of a descriptive scale instead could have avoided the issue of individual variation. The fact that radiographs were not taken for every sedation episode might have also induced some errors in this score. Second, the sedation scale used, although validated, does not include a cutoff value to determine when a sufficient level of sedation has been achieved; this was determined subjectively by a single observer. Finally, the injection of dexmedetomidine SC in the interscapular region was not randomized and the evaluation was not done with blinding, so the results from this sedation episode should be interpreted with caution.

In conclusion, SC administration of 200 μg/m2 of dexmedetomidine on the head is efficient for conducting orthopedic radiographic examinations in healthy dogs. Administration of dexmedetomidine SC at the GV20 acupuncture point provides a level of sedation clinically comparable to that achieved with SC administration at the base of the ear.

Acknowledgments

We thank all the dog owners who agreed to participate in this study, as well as Dr. Olivia Price, who generously provided the anesthesia head hoods (Mil*Dog Designs). CVJ

Funding Statement

This study was funded by the Companion Animals Health Fund from the Faculty of Veterinary Medicine of the University of Montreal, supported by Zoetis.

Footnotes

Unpublished supplementary material (Tables S1, S2) is available online from: www.canadianveterinarians.net

Use of this article is limited to a single copy for personal study. Anyone interested in obtaining reprints should contact the CVMA office (kgray@cvma-acmv.org) for additional copies or permission to use this material elsewhere.

This study was funded by the Companion Animals Health Fund from the Faculty of Veterinary Medicine of the University of Montreal, supported by Zoetis.

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