Evaluation of subcutaneous administration of alfaxalone-midazolam and ketamine-midazolam as sedation protocols in African pygmy hedgehogs (Atelerix albiventris)

Shawna J. Hawkins Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706.

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Grayson A. Doss Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706.

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Christoph Mans Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI 53706.

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Abstract

OBJECTIVE

To evaluate SC administration of 2 sedation protocols, ketamine-midazolam (KM) and alfaxalone-midazolam (AM), in African pygmy hedgehogs (Atelerix albiventris).

ANIMALS

9 healthy adult hedgehogs (5 males, 4 females).

PROCEDURES

A randomized, blinded, complete crossover study was performed. Sedation was induced by SC administration of either ketamine (30 mg/kg [14 mg/lb]) with midazolam (1 mg/kg [0.45 mg/lb]) or alfaxalone (3 mg/kg [1.4 mg/lb]) with midazolam (1 mg/kg), including a 2-week washout period between treatments. Flumazenil (0.05 mg/kg [0.02 mg/lb], SC) was administered 45 minutes after administration of either protocol to reverse the effects of midazolam. Physiologic variables, reflexes, and behaviors were monitored. Food intake and body weight were measured before and after sedation.

RESULTS

Deep sedation characterized by complete loss of the righting reflex, decreased jaw tone, decreased pelvic limb withdrawal reflex, and preservation of the palpebral reflex was produced in 7 of 9 hedgehogs after KM administration and all 9 hedgehogs after AM administration. Mean ± SD time to loss of righting reflex was 6.4 ± 2.4 minutes after KM administration and 10 ± 4.0 minutes after AM administration. Following flumazenil administration, no significant difference was found in recovery time between sedation with KM (18.8 ± 12.7 minutes) and AM (14.4 ± 7.8 minutes). No significant differences were found in respiratory rate, oxygen saturation, or body temperature between protocols, whereas heart rate was higher for sedation with KM. Both sedation protocols resulted in a transient reduction in food intake.

CONCLUSIONS AND CLINICAL RELEVANCE

Subcutaneous administration of KM and AM provided deep sedation that might be useful to facilitate routine, noninvasive procedures in hedgehogs.

Abstract

OBJECTIVE

To evaluate SC administration of 2 sedation protocols, ketamine-midazolam (KM) and alfaxalone-midazolam (AM), in African pygmy hedgehogs (Atelerix albiventris).

ANIMALS

9 healthy adult hedgehogs (5 males, 4 females).

PROCEDURES

A randomized, blinded, complete crossover study was performed. Sedation was induced by SC administration of either ketamine (30 mg/kg [14 mg/lb]) with midazolam (1 mg/kg [0.45 mg/lb]) or alfaxalone (3 mg/kg [1.4 mg/lb]) with midazolam (1 mg/kg), including a 2-week washout period between treatments. Flumazenil (0.05 mg/kg [0.02 mg/lb], SC) was administered 45 minutes after administration of either protocol to reverse the effects of midazolam. Physiologic variables, reflexes, and behaviors were monitored. Food intake and body weight were measured before and after sedation.

RESULTS

Deep sedation characterized by complete loss of the righting reflex, decreased jaw tone, decreased pelvic limb withdrawal reflex, and preservation of the palpebral reflex was produced in 7 of 9 hedgehogs after KM administration and all 9 hedgehogs after AM administration. Mean ± SD time to loss of righting reflex was 6.4 ± 2.4 minutes after KM administration and 10 ± 4.0 minutes after AM administration. Following flumazenil administration, no significant difference was found in recovery time between sedation with KM (18.8 ± 12.7 minutes) and AM (14.4 ± 7.8 minutes). No significant differences were found in respiratory rate, oxygen saturation, or body temperature between protocols, whereas heart rate was higher for sedation with KM. Both sedation protocols resulted in a transient reduction in food intake.

CONCLUSIONS AND CLINICAL RELEVANCE

Subcutaneous administration of KM and AM provided deep sedation that might be useful to facilitate routine, noninvasive procedures in hedgehogs.

African pygmy hedgehogs (Atelerix albiventris) are popular companion animals with a unique defense mechanism that makes examination difficult without chemical restraint. A main defense is the ability to curl into a ball, covering the body with their dorsum of keratinous spines termed the mantle, which limits access to the head, limbs, and ventrum.1 Isoflurane anesthesia, typically via chamber induction and maintained with a face mask, is the most common method of immobilization for hedgehogs when performing physical examinations, diagnostic tests, and procedures.1–3

A number of anecdotal injectable anesthetic protocols for African pygmy hedgehogs are reported, with common combinations including a dissociative agent with a benzodiazepine or α2-adrenergic receptor agonist, but suggested dosages vary widely and no information is available regarding efficacy or safety; therefore, these reported anesthetic drug combinations should be used with caution.1,2,4–6 Reports7,8 of successful injectable anesthesia in the European hedgehog (Erinaceus europaeus) and tenrec (Echinops telfairi) with the administration of medetomidine and ketamine are found, but no prospective research studies exist examining injectable anesthesia or sedation protocols in the African pygmy hedgehog. Ketamine is a dissociative agent commonly used in small mammals and recommended for use in combination with other injectable sedatives, as it can result in poor muscle relaxation and rough recoveries as a sole sedation agent.9 Ketamine administration in combination with medetomidine in rabbits results in loss of the righting reflex for 68 minutes when administered IM and 109 minutes when administered SC.10

Midazolam is a short-acting benzodiazepine often used for premedication, because it has added sedative and muscle relaxant effects when combined with opioids or dissociative agents.3,9 Midazolam has minimal cardiovascular effects, making it useful in compromised or debilitated small mammals.9 When used in combination with ketamine in rabbits, IM administration of midazolam results in loss of the righting reflex in < 3 minutes with a duration of anesthesia of 55 minutes.11

Alfaxalone is a neuroactive steroid anesthetic that is gaining popularity in exotic animal medicine because of its ability to be used via SC and IM routes. Alfaxalone has proven to be a safe, reliable, singleagent anesthetic in rabbits, lasting up to 35 to 60 minutes when administered IM depending on the dose or < 10 minutes when administered IV.12,13 Dose-dependent respiratory depression secondary to alfaxalone administration has been shown in rabbits, rats, ferrets, and guinea pigs.13–16

The purpose of the study reported here was to evaluate 2 injectable sedation protocols (KM and AM) to provide alternative options to inhalant anesthesia for noninvasive procedures, such as physical examination and diagnostic imaging in African pygmy hedgehogs. Our hypothesis was that both sedation protocols would provide a rapid onset of deep sedation suitable to perform a complete physical examination and to position in dorsal recumbency for diagnostic imaging for ≥ 30 minutes.

Materials and Methods

Animals

This study was approved by the University of Wisconsin-Madison School of Veterinary Medicine Institutional Animal Care and Use Committee (protocol V006051). Nine captive-bred African pygmy hedgehogs (5 males and 4 females) that were 7 to 8 months old with a mean ± SD body weight of 404 ± 59 g (0.89 ± 0.13 lb) were used in this study. Animals were housed in a climate-controlled room with a 12:12 hour photoperiod and room temperature of 27°C (80°F). Hedgehogs were housed individually in ventilated enclosures measuring 84 × 51 × 36 cm. Each enclosure was lined with a cardboard substrate, contained a hide box and exercise wheel, and included shredded paper for digging. Hedgehogs were offered fresh water ad libitum in a bowl and maintained on a commercial hedgehog diet.a All hedgehogs were acclimated to the housing for several months prior to the study and were deemed healthy on the basis of serial physical examination findings and long-term monitoring of food intake and body weight. Food was not withheld prior to the sedation studies. Trials occurred in a separate climate-controlled room maintained within 3°C (5°F) of the housing room temperature.

Sedation protocols

Pilot studies were conducted to evaluate the efficacy of various doses of KM and AM administered SC. The goal was to identify dosage combinations that would result in complete loss of the righting reflex for ≥ 30 minutes without a protracted recovery period, following reversal with flumazenilb administration at 45 minutes. Dose combinations were evaluated in a minimum of 2 hedgehogs. Initial doses were administered on the basis of anecdotal reports,2,4,17,18 and doses of alfaxalone, ketamine, and midazolam were increased or decreased on the basis of the sedation level achieved until efficacious combinations were found. Protocols combining either ketaminec (30 mg/kg [14 mg/lb], SC) with midazolamd (1 mg/kg [0.45 mg/lb], SC) or alfaxalonee (3 mg/kg [1.4 mg/lb], SC) with midazolam (1 mg/kg, SC) were determined to be suitable and therefore used in the final study. Flumazenil (0.05 mg/kg [0.02 mg/lb], SC) was administered 45 minutes after administration of either protocol to reverse the effects of midazolam.

Study design and procedure

In a randomized, blinded, complete crossover study with a minimum of a 2-week washout period between treatments, 2 sedation protocols (ie, KM and AM) were evaluated in 9 hedgehogs. Drugs were administered in a single syringe SC in the mantle, dorsal to the right thoracic limb.

Data collection

All sedation variables were recorded by a single observer (SJH). Physiologic variables including heart rate, respiratory rate, Spo2, and rectal temperature were recorded every 5 minutes after SC injection of KM or AM. Heart rate and Spo2 were measured with a pulse oximetry probe placed on a metacarpal paw pad. Respiratory rate was obtained by counting visible thoracic expansions. If the hedgehog was emitting defensive hissing vocalizations, the respiratory rate was routinely > 100 breaths/min and was subsequently recorded as 100 breaths/min. Because of the defensive nature of hedgehogs, respiratory rate was the only baseline variable able to be recorded prior to onset of sedation. Hedgehogs were provided 100% oxygen (2 L/min) via face mask during the trials, starting 5 minutes following sedative administration and continuing until the righting reflex was regained. Thermal support was provided at all times during sedation events with a recirculating water blanket.

Recorded sedation variables included palpebral, righting, and pelvic limb withdrawal reflexes as well as jaw tone; these reflexes were evaluated at 5-minute intervals following sedative administration. Reflexes and jaw tone were graded as normal, reduced or delayed, or absent (Appendix).

Physiologic variables, reflexes, and jaw tone were monitored after flumazenil injection administration (at 45 minutes after sedative administration) until recovery, which was defined as a return of the righting reflex.

Body weight and food intake (g/kg of body weight) were measured every 24 hours in the morning during the same 1-hour window. Baseline values were obtained 24 hours prior to each trial, and data collection continued for 6 days.

Statistical analysis

Randomization of the treatment sequence was performed with online software,f and data were analyzed with commercial software.g Data were tested for normality by use of the Shapiro-Wilk test and for equal variance with the Brown Forsythe test. Simple data transformation was performed when necessary. Heart rate, respiratory rate, rectal temperature, Spo2, food intake, and body weight were analyzed with a 2-way repeated-measures ANOVA. Comparisons between treatments for time to loss of righting reflex, duration of loss of righting reflex, total food intake, jaw tone, and recovery time were performed by use of a paired t test. Significance was defined as P < 0.05. Data are reported as mean ± SD unless indicated otherwise.

Results

Deep sedation characterized by complete loss of the righting reflex, decreased jaw tone, decreased pelvic limb withdrawal reflex, and preservation of the palpebral reflex was produced in 7 of 9 hedgehogs after KM administration and all 9 hedgehogs after AM administration.

Following KM administration, the righting reflex was lost in 7 of 9 animals and the mean ± SD time to loss of this reflex was 6.4 ± 2.4 minutes. After AM administration, all 9 hedgehogs lost the righting reflex, and the mean time to loss of this reflex was 10 ± 4.0 minutes. The duration of loss of the righting reflex was 38.5 ± 9.5 minutes after KM administration and 42.1 ± 7.0 minutes after AM administration. No significant differences were found between treatments for time to loss of the righting reflex or the duration of the loss of the righting reflex.

The palpebral reflex was maintained in all animals for both treatments at all time points. A decrease in jaw tone was noted in all animals, and jaw tone was completely lost in 5 of 9 animals after AM administration and 4 of 9 animals after KM administration. The pelvic limb withdrawal response remained in 8 of 9 animals after sedation with KM and all 9 animals after sedation with AM.

After sedation with KM, all hedgehogs showed signs of recovery prior to reversal with flumazenil as early as 30 minutes after KM administration, including mild cutaneous trunci fasciculation and intermittent, mild trembling of the limbs. In contrast, after sedation with AM, none of the hedgehogs demonstrated any signs of recovery until after flumazenil was administered. Following flumazenil administration, no significant difference was found in recovery time for hedgehogs between sedation with KM (18.8 ± 12.7 minutes) and sedation with AM (14.4 ± 7.8 minutes). After KM administration, 6 of 7 hedgehogs that were still sedated by the 45-minute mark showed signs of hyperactive ambulation after reversal with flumazenil, which was characterized by repetitive pacing in their enclosure. In contrast, after AM administration, 8 of 9 animals adopted a defensive body position by balling up after reversal with flumazenil.

Heart rate was significantly (P = 0.007) higher during the 20- to 45-minute time points following sedation with KM, compared with baseline measurements (Figure 1). Spontaneous breathing was maintained throughout the sedation period in all animals. Respiratory rate decreased significantly (P < 0.001) from baseline for both treatments following induction of sedation (Figure 2). No clinically relevant differences were found in respiratory rate between treatments, although mean respiratory rate was significantly higher at the 40-minute time point for the animals after KM administration. No significant difference was found in rectal temperature of hedgehogs between treatments. Mean starting body temperatures at 5 minutes after sedation were 33.4°C (92.2°F) and 32.8°C (91.1°F), and final body temperatures at 45 minutes were 33.3°C (91.9°F) and 32.7°C (90.8°F) for KM and AM treatments, respectively. No significant difference was found in Spo2 values between or within treatments at any time point.

Figure 1—
Figure 1—

Mean ± SEM heart rate for 9 African pygmy hedgehogs (Atelerix albiventris) sedated with either KM or AM, administered SC in a randomized, blinded, complete crossover study with a minimum of a 2-week washout period. The first and last heart rate measurements were obtained at 10 and 45 minutes, respectively, after administration of KM or AM. Flumazenil was administered SC at 45 minutes after administration of KM or AM. *Significant (P < 0.05) difference from baseline within the same treatment. †Significant (P < 0.05) difference between treatments.

Citation: Journal of the American Veterinary Medical Association 257, 8; 10.2460/javma.257.8.820

Figure 2—
Figure 2—

Mean ± SEM respiratory rate for 9 African pygmy hedgehogs sedated with either KM or AM, administered SC, in a randomized, blinded, complete crossover study with a minimum of a 2-week washout period. Baseline measurements were obtained 5 minutes prior to (−5 minutes) and at the time of KM or AM administration (0 minutes). Flumazenil was administered SC at 45 minutes after administration of KM or AM. See Figure 1 for remainder of key.

Citation: Journal of the American Veterinary Medical Association 257, 8; 10.2460/javma.257.8.820

During the 48 hours following sedation, both protocols resulted in an overall decrease in food intake (KM, 55 ± 30% decrease; AM, 3 ± 86% decrease) from baseline (day −1) levels (Figure 3). After sedation with AM, hedgehogs had an initial increase in food intake above baseline during the first 24 hours after sedation (day 1) followed by a decrease below baseline at day 2; these fluctuations were not significantly (P > 0.7) different from baseline values. After sedation with KM, food intake on both day 1 and day 2 was significantly (P ≤ 0.02) lower than baseline values. Between treatments, a significant (P < 0.001) difference was found in food intake during the first 24 hours (day 1) after sedation. For day 1, mean food intake of hedgehogs after sedation with KM decreased by 42 ± 52%, whereas mean food intake of hedgehogs after sedation with AM increased by 16 ± 18%. The total amount of food consumed by each animal over the 6 days after sedation was less, but not significantly (P = 0.08), following KM sedation (104 ± 29 g/kg [47.3 ± 13.2 g/lb]), compared with intake following AM sedation (152 ± 62 g/kg [69.0 ± 28.2 g/lb]).

Figure 3—
Figure 3—

Mean ± SEM food intake for 9 African pygmy hedgehogs sedated with either KM or AM, administered SC, in a randomized, blinded, complete crossover study with a minimum of a 2-week washout period. Baseline food intake measurements were obtained 1 day prior to sedation (day −1), and intake was measured daily for 6 days afterwards. Values for day 1 correspond to food intake over the previous 24 hours, which includes the sedation event. See Figure 1 for remainder of key.

Citation: Journal of the American Veterinary Medical Association 257, 8; 10.2460/javma.257.8.820

Body weight of hedgehogs decreased significantly (P < 0.015) on day 2 after KM sedation (3 ± 2% decrease), compared with baseline body weight, but not (P = 0.72) following AM sedation (1 ± 3% decrease). By day 6 after sedation, mean body weight had increased by 0 ± 2% following KM sedation (P = 0.9) and by 2 ± 3% following AM sedation (P = 0.39), compared with baseline. No significant (P > 0.7) difference was found in body weight between treatments at any time point.

Discussion

The goal of this study was to evaluate 2 SC sedation protocols in African pygmy hedgehogs to determine whether they could provide sufficient sedation to perform a physical examination, intraoral examination, and noninvasive diagnostic procedures such as diagnostic imaging. All hedgehogs that lost the righting reflex during the trials were considered to be heavily sedated. This sedation level was characterized by a decreased response to stimuli, decreased heart rate, decreased respiratory rate, and loss of the righting reflex with retention of at least 2 reflexes (typically palpebral and pelvic limb withdrawal). Loss of the righting reflex and decreased ability to ball up indicate a physical examination as well as procedures such as diagnostic imaging could be performed with these protocols. Intubation was not attempted in this study. However, most of the hedgehogs after both sedation protocols were responsive to tongue manipulation during assessment of jaw tone, suggesting the hedgehogs were not at a sufficient depth for successful endotracheal intubation.

Subjectively, hedgehogs sedated with AM were less reactive to stimuli and had smoother recovery periods. Hedgehogs sedated with KM showed signs of arousal prior to reversal (cutaneous trunci fasciculation and intermittent limb shaking), whereas animals administered AM did not show signs of recovery until after flumazenil was administered. On the basis of these observations, the authors felt that the AM sedation protocol provided better-quality sedation, although this was not objectively scored.

Recovery times for both protocols were similar following the administration of flumazenil. Interestingly, most hedgehogs after KM administration were found to be hyperactive after administration of flumazenil, whereas most hedgehogs after AM administration preferred to remain in a balled-up, defensive posture. Because ketamine can cause erratic and unpredictable anesthesia in small mammals if used as a sole anesthetic agent, it is commonly used in combination with other anesthetic agents such as α2-adrenergic receptor agonists or benzodiazepines.1,3 Emergence delirium, which includes ataxia and increased motor activity during the anesthetic recovery period, has been described in small laboratory mammals administered ketamine.9 One possibility for the erratic behavior witnessed with the KM sedation is that the ketamine may not have been fully metabolized by 45 minutes when the sedative effects of midazolam were reversed, leading to a hyperactive state. Although pharmacokinetic data evaluating ketamine in small mammals are sparse, the drug's duration as a single agent in rabbits is approximately 60 minutes.2,19

This was the first study that evaluated the effect of chemical restraint on food intake and body weight in a hedgehog species. The overall food intake over the 6-day period following sedation was lower following KM sedation, compared with AM sedation. The greater reduction in food intake following KM treatment correlated with the greater reduction in body weight. Although the clinical ramifications of the decrease in food consumption with these injectable protocols are unknown, daily observation of each animal during the study did not reveal any overt abnormalities, food consumption returned to normal within the study period, and body weight alterations were small. These injectable protocols should be used cautiously in debilitated animals, as a decrease in food intake or body weight may have a more profound effect than observed with the healthy hedgehogs in the present study. It is unknown whether inhalant anesthesia would be preferred in these instances. Isoflurane anesthesia in hedgehogs resulted in less or similar effects on food intake and body weight when compared to the changes noted with the injectable protocols in this study.20

Limitations in the present study included the inability to obtain baseline measurements for most monitored variables, which was precluded by the normal behavior of the hedgehogs. Their defensive nature also prevented collection of further data after return of reflexes during the recovery period.

In conclusion, administration of either KM or AM at the dosages evaluated in the present study resulted in sedation in African pygmy hedgehogs, which could facilitate examination and nonpainful procedures like diagnostic imaging. Subjectively, KM sedation effects were less consistent, with premature arousal occurring in all animals prior to reversal. Additionally, KM sedation had more pronounced effects on food intake and body weight, compared with AM sedation.

ABBREVIATIONS

AM

Alfaxalone-midazolam

KM

Ketamine-midazolam

Spo2

Oxygen saturation as measured by pulse oximetry

Footnotes

a.

Spike's Delite Premium Diet, Pet-Pro Products, Middletown, Mo.

b.

West-Ward Pharmaceuticals Corp, Eatontown, NJ.

c.

Ketamine hydrochloride injection, Hospira Inc, Lake Forest, Ill.

d.

West-Ward Pharmaceuticals Corp, Eatontown, NJ.

e.

Alfaxan, Jurox Pty Ltd, Newcastle, NSW, Australia.

f.

Research Randomizer, version 4.0, Urbaniak GC, Plous S, Middletown, Conn. Available at: www.randomizer.org. Accessed Sep 17, 2018.

g.

SigmaPlot, version 13, Systat Software, San Jose, Calif.

References

  • 1. Heatley JJ. Hedgehogs. In: Mitchell MA, Tully TN, eds. Manual of exotic pet practice. St Louis: Saunders Elsevier, 2009;433455.

  • 2. Helmer PJ, Carpenter JW. Hedgehogs. In: Carpenter JW, ed. Exotic animal formulary. 5th ed. St Louis: Elsevier, 2018;444459.

  • 3. Doss G, Carpenter J. African pygmy hedgehogs. In: Quesenberry K, Orcutt C, Mans C, Carpenter J, eds. Ferrets, rabbits, and rodents: clinical medicine and surgery. 4th ed. St. Louis: Elsevier, 2020;401415.

    • Search Google Scholar
    • Export Citation
  • 4. Heard D. Insectivores. In: West G, Heard D, Caulkett N, eds. Zoo animal and wildlife immobilization and anesthesia. 2nd ed. Ames, Iowa: Wiley Blackwell, 2014;529532.

    • Search Google Scholar
    • Export Citation
  • 5. Hoefer HL. Hedgehogs. Vet Clin North Am Small Anim Pract 1994;24:113120.

  • 6. Lightfoot TL. Therapeutics of African pygmy hedgehogs and prairie dogs. Vet Clin North Am Exot Anim Pract 2000;3:155172.

  • 7. Henke J, Reinert J, Preissel AK, et al. Partially antagonisable anaesthesia of the small hedgehog tenrec (Echinops telfairi) with medetomidine, midazolam and ketamine. J Exp Anim Sci 2007;43:255264.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 8. Arnemo JM, S⊘li NE. Chemical immobilization of free-ranging European hedgehogs (Erinaceus europaeus). J Zoo Wildl Med 1995;26:246251.

    • Search Google Scholar
    • Export Citation
  • 9. Lester PA, Moore RM, Shuster KA, et al. Anesthesia and analgesia. In: Suckow MA, Stevens KA, Wilson RP, eds. The laboratory rabbit, guinea pig, hamster, and other rodents. Waltham, Mass: Elsevier, 2012;3458.

    • Search Google Scholar
    • Export Citation
  • 10. Williams AM, Wyatt JD. Comparison of subcutaneous and intramuscular ketamine-medetomidine with and without reversal by atipamezole in Dutch belted rabbits (Oryctolagus cuniculus). J Am Assoc Lab Anim Sci 2007;46:1620.

    • Search Google Scholar
    • Export Citation
  • 11. Grint NJ, Murison PJ. A comparison of ketamine-midazolam and ketamine-medetomidine combinations for induction of anaesthesia in rabbits. Vet Anaesth Analg 2008;35:113121.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 12. Gil AG, Silván G, Villa A, et al. Heart and respiratory rates and adrenal response to propofol or alfaxalone in rabbits. Vet Rec 2012;170:444.

  • 13. Huynh M, Poumeyrol S, Pignon C, et al. Intramuscular administration of alfaxalone for sedation in rabbits. Vet Rec 2015;176:255.

  • 14. Lau C, Ranasinghe MG, Shiels I, et al. Plasma pharmacokinetics of alfaxalone after a single intraperitoneal or intravenous injection of Alfaxan in rats. J Vet Pharmacol Ther 2013;36:516520.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 15. Schwenke DO, Cragg PA. Comparison of the depressive effects of four anesthetic regimens on ventilator and cardiovascular variables in the guinea pig. Comp Med 2004;54:7785.

    • Search Google Scholar
    • Export Citation
  • 16. Giral M, García-Olmo DC, Gómez-Juárez M, et al. Anaesthetic effects in the ferret of alfaxalone alone and in combination with medetomidine or tramadol: a pilot study. Lab Anim 2014;48:313320.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 17. Longley L. Anaesthesia of other small mammals. In: Longley L, Fiddes M, O'Brien M, eds. Anaesthesia of exotic pets. St Louis: Saunders Elsevier, 2008;96102.

    • Search Google Scholar
    • Export Citation
  • 18. Pye GW. Marsupial, insectivore, and chiropteran anesthesia. Vet Clin North Am Exot Anim Pract 2001;4:211237.

  • 19. Pedraz JL, Lanao JM, Dominguez-Gil A. Kinetics of ketamine and its metabolites in rabbits with normal and impaired renal function. Eur J Drug Metab Pharmacokinet 1985;10:3339.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 20. Hawkins SJ, Doss GA, Mans C. Postanesthetic effects of two durations of isoflurane anesthesia in African pygmy hedgehogs (Atelerix albiventris). J Exot Pet Med 2020;32:2730.

    • Crossref
    • Search Google Scholar
    • Export Citation

Appendix

Sedation grading system used to evaluate reflexes and jaw tone in 9 African pygmy hedgehogs sedated by SC administration of KM or AM.

 Variables  
VariablesNormalDelayedAbsent
Palpebral reflexHedgehog blinked immediately upon gentle touching of the lateral and medial canthi of the eye.Blinking was delayed or eyelids did not completely close upon gently touching of the lateral and medial canthi of the eye.Hedgehog did not blink upon gentle touching of the lateral and medial canthi of the eye.
Righting reflexHedgehog immediately assumed defensive, balled-up body position when handled. Observer could not restrain by scruffing mantle. Stethoscope could not be placed on ventral aspect of thorax.Hedgehog attempted to ball up in defensive posture when handled but posture was weak and balling up was incomplete. Observer could restrain by scruffing mantle. Stethoscope could not be placed on ventral aspect of thorax.Hedgehog made no attempt to ball up into defensive posture when handled.
Pelvic limb withdrawal reflexHedgehog immediately withdrew pelvic limb away from stimulus when metatarsal pad was pinched with cushioned hemostatic forceps with steady, gentle force.Withdrawal of pelvic limb away from stimulus was delayed at least 2 s when metatarsal pad was pinched with cushioned hemostatic forceps with steady, gentle force.No attempt made to withdraw pelvic limb away from stimulus when metatarsal pad was pinched with cushioned hemostatic forceps with steady, gentle force.
Jaw toneAttempt to open mouth was met with great resistance. An oral examination could not be performed.Mouth could be opened and oral examination could be performed. Hedgehog responded to an attempt to withdraw tongue from oral cavity.Mouth could be opened entirely. Oral examination could be performed and hedgehog did not respond to tongue being withdrawn from oral cavity.
  • Figure 1—

    Mean ± SEM heart rate for 9 African pygmy hedgehogs (Atelerix albiventris) sedated with either KM or AM, administered SC in a randomized, blinded, complete crossover study with a minimum of a 2-week washout period. The first and last heart rate measurements were obtained at 10 and 45 minutes, respectively, after administration of KM or AM. Flumazenil was administered SC at 45 minutes after administration of KM or AM. *Significant (P < 0.05) difference from baseline within the same treatment. †Significant (P < 0.05) difference between treatments.

  • Figure 2—

    Mean ± SEM respiratory rate for 9 African pygmy hedgehogs sedated with either KM or AM, administered SC, in a randomized, blinded, complete crossover study with a minimum of a 2-week washout period. Baseline measurements were obtained 5 minutes prior to (−5 minutes) and at the time of KM or AM administration (0 minutes). Flumazenil was administered SC at 45 minutes after administration of KM or AM. See Figure 1 for remainder of key.

  • Figure 3—

    Mean ± SEM food intake for 9 African pygmy hedgehogs sedated with either KM or AM, administered SC, in a randomized, blinded, complete crossover study with a minimum of a 2-week washout period. Baseline food intake measurements were obtained 1 day prior to sedation (day −1), and intake was measured daily for 6 days afterwards. Values for day 1 correspond to food intake over the previous 24 hours, which includes the sedation event. See Figure 1 for remainder of key.

  • 1. Heatley JJ. Hedgehogs. In: Mitchell MA, Tully TN, eds. Manual of exotic pet practice. St Louis: Saunders Elsevier, 2009;433455.

  • 2. Helmer PJ, Carpenter JW. Hedgehogs. In: Carpenter JW, ed. Exotic animal formulary. 5th ed. St Louis: Elsevier, 2018;444459.

  • 3. Doss G, Carpenter J. African pygmy hedgehogs. In: Quesenberry K, Orcutt C, Mans C, Carpenter J, eds. Ferrets, rabbits, and rodents: clinical medicine and surgery. 4th ed. St. Louis: Elsevier, 2020;401415.

    • Search Google Scholar
    • Export Citation
  • 4. Heard D. Insectivores. In: West G, Heard D, Caulkett N, eds. Zoo animal and wildlife immobilization and anesthesia. 2nd ed. Ames, Iowa: Wiley Blackwell, 2014;529532.

    • Search Google Scholar
    • Export Citation
  • 5. Hoefer HL. Hedgehogs. Vet Clin North Am Small Anim Pract 1994;24:113120.

  • 6. Lightfoot TL. Therapeutics of African pygmy hedgehogs and prairie dogs. Vet Clin North Am Exot Anim Pract 2000;3:155172.

  • 7. Henke J, Reinert J, Preissel AK, et al. Partially antagonisable anaesthesia of the small hedgehog tenrec (Echinops telfairi) with medetomidine, midazolam and ketamine. J Exp Anim Sci 2007;43:255264.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 8. Arnemo JM, S⊘li NE. Chemical immobilization of free-ranging European hedgehogs (Erinaceus europaeus). J Zoo Wildl Med 1995;26:246251.

    • Search Google Scholar
    • Export Citation
  • 9. Lester PA, Moore RM, Shuster KA, et al. Anesthesia and analgesia. In: Suckow MA, Stevens KA, Wilson RP, eds. The laboratory rabbit, guinea pig, hamster, and other rodents. Waltham, Mass: Elsevier, 2012;3458.

    • Search Google Scholar
    • Export Citation
  • 10. Williams AM, Wyatt JD. Comparison of subcutaneous and intramuscular ketamine-medetomidine with and without reversal by atipamezole in Dutch belted rabbits (Oryctolagus cuniculus). J Am Assoc Lab Anim Sci 2007;46:1620.

    • Search Google Scholar
    • Export Citation
  • 11. Grint NJ, Murison PJ. A comparison of ketamine-midazolam and ketamine-medetomidine combinations for induction of anaesthesia in rabbits. Vet Anaesth Analg 2008;35:113121.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 12. Gil AG, Silván G, Villa A, et al. Heart and respiratory rates and adrenal response to propofol or alfaxalone in rabbits. Vet Rec 2012;170:444.

  • 13. Huynh M, Poumeyrol S, Pignon C, et al. Intramuscular administration of alfaxalone for sedation in rabbits. Vet Rec 2015;176:255.

  • 14. Lau C, Ranasinghe MG, Shiels I, et al. Plasma pharmacokinetics of alfaxalone after a single intraperitoneal or intravenous injection of Alfaxan in rats. J Vet Pharmacol Ther 2013;36:516520.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 15. Schwenke DO, Cragg PA. Comparison of the depressive effects of four anesthetic regimens on ventilator and cardiovascular variables in the guinea pig. Comp Med 2004;54:7785.

    • Search Google Scholar
    • Export Citation
  • 16. Giral M, García-Olmo DC, Gómez-Juárez M, et al. Anaesthetic effects in the ferret of alfaxalone alone and in combination with medetomidine or tramadol: a pilot study. Lab Anim 2014;48:313320.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 17. Longley L. Anaesthesia of other small mammals. In: Longley L, Fiddes M, O'Brien M, eds. Anaesthesia of exotic pets. St Louis: Saunders Elsevier, 2008;96102.

    • Search Google Scholar
    • Export Citation
  • 18. Pye GW. Marsupial, insectivore, and chiropteran anesthesia. Vet Clin North Am Exot Anim Pract 2001;4:211237.

  • 19. Pedraz JL, Lanao JM, Dominguez-Gil A. Kinetics of ketamine and its metabolites in rabbits with normal and impaired renal function. Eur J Drug Metab Pharmacokinet 1985;10:3339.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 20. Hawkins SJ, Doss GA, Mans C. Postanesthetic effects of two durations of isoflurane anesthesia in African pygmy hedgehogs (Atelerix albiventris). J Exot Pet Med 2020;32:2730.

    • Crossref
    • Search Google Scholar
    • Export Citation

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