• 1.

    Wells K, Butterworth A, Richards N. A review of secondary pentobarbital poisoning in scavenging wildlife, companion animals and captive carnivores. J Vet Forensic Sci 2020;1:115.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 2.

    Chinnadurai SK, Strahl-Heldreth D, Fiorello CV, et al.. Best-practice guidelines for field-based surgery and anesthesia of free-ranging wildlife. Anesthesia I. and analgesia. J Wildl Dis 2016;52(suppl 2):S14S27.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 3.

    Leary S, Underwood W, Anthony R, et al.. AVMA guidelines for the euthanasia of animals: 2020 edition. Schaumburg, Ill: AVMA, 2020.

  • 4.

    Diercks DB, Shumaik GM, Harrigan RA, et al.. Electrocardiographic manifestations: electrolyte abnormalities. J Emerg Med 2004;27:153160.

  • 5.

    Vassalle M, Greenspan K, Jomain S, et al.. Effects of potassium on automaticity and conduction of canine hearts. Am J Physiol 1964;207:334340.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 6.

    Harms CA, McLellan WA, Moore MJ, et al.. Low-residue euthanasia of stranded mysticetes. J Wildl Dis 2014;50:6373.

  • 7.

    Shearer JK. Euthanasia of cattle: practical considerations and application. Animals (Basel) 2018;8:117.

  • 8.

    Cartner SC, Barlow SC, Ness TJ. Loss of cortical function in mice after decapitation, cervical dislocation, potassium chloride injection, and CO2 inhalation. Comp Med 2007;57:570573.

    • Search Google Scholar
    • Export Citation
  • 9.

    Louis MM, Houck EL, Lewbart GA, et al.. Evaluation of potassium chloride administered via three routes for euthanasia of anesthetized koi (Cyprinus carpio). J Zoo Wildl Med 2020;51:485489.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 10.

    Raghav R, Taylor M, Guincho M, et al.. Potassium chloride as a euthanasia agent in psittacine birds: clinical aspects and consequences for histopathologic assessment. Can Vet J 2011;52:303306.

    • Search Google Scholar
    • Export Citation
  • 11.

    Doerr M, Stoskopf MK. Evaluation of euthanasia of moon jellyfish (Aurelia aurita) using simple salt solutions. J Zoo Wildl Med 2019;50:123126.

  • 12.

    Battison A, MacMillan R, MacKenzie A, et al.. Use of injectable potassium chloride for euthanasia of American lobsters (Homarus americanus). Comp Med 2000;50:545550.

    • Search Google Scholar
    • Export Citation
  • 13.

    Bennie NAC, Loaring CD, Bennie MMG, et al.. An effective method for terrestrial arthropod euthanasia. J Exp Biol 2012;215:42374241.

  • 14.

    Barco SG, Walton WJ, Harms CA, et al.. Collaborative development of recommendations for euthanasia of stranded cetaceans. NOAA technical memorandum NMFS-OPR-56. Washington, DC: US Department of Commerce, 2016;183.

    • Search Google Scholar
    • Export Citation
  • 15.

    Daoust PY, Ortenburger AI. Successful euthanasia of a juvenile fin whale. Can Vet J 2001;42:127129.

  • 16.

    Harms CA, Greer L, Whaley J, et al.. Euthanasia. In: Gulland FMD, Dierauf LA, eds. Marine mammal medicine. 3rd ed. Boca Raton, Fla: CRC Press Inc, 2018;675691.

    • Search Google Scholar
    • Export Citation
  • 17.

    Greig DJ, Gulland FMD, Kreuder C. A decade of live California sea lion (Zalophus californianus) strandings along the Central California coast: causes and trends, 1991–2000. Aquat Mamm 2005;31:1122.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 18.

    LeBoeuf BJ, Laws RM eds. Elephant seals: population ecology, behavior, and physiology. Berkeley, Calif: University of California Press, 1994.

    • Search Google Scholar
    • Export Citation
  • 19.

    Le Boeuf BJ, Whiting RJ, Gantt RF. Perinatal behavior of northern elephant seal females and their young. Behaviour 1972;43:121156.

  • 20.

    Barbieri M. Health assessment of seals and sea lions. In: Gulland FMD, Dierauf LA, eds. Marine mammal medicine. 3rd ed. Boca Raton, Fla: CRC Press Inc, 2018;849856.

    • Search Google Scholar
    • Export Citation
  • 21.

    Loeffler IK. Euthanasia in veterinary field projects. In: Polak KA, Kommedal T, eds. Field manual for small animal medicine. Hoboken, NJ: John Wiley & Sons, 2018;289306.

    • Search Google Scholar
    • Export Citation
  • 22.

    Wijdicks EFM, Varelas PN, Gronseth GS, et al.. Evidence-based guideline update: determining brain death in adults. Neurology 2010;74:19111918.

  • 23.

    Goldstein T, Mazet JAK, Zabka TS, et al.. Novel symptomatology and changing epidemiology of domoic acid toxicosis in California sea lions (Zalophus californianus): an increasing risk to marine mammal health. Proc R Soc B Biol Sci 2008;275:267276.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 24.

    Rommel SA, Costidis AM, Lowenstine LJ. Gross and microscopic anatomy. In: Gulland FMD, Dierauf LA, eds. Marine mammal medicine. 3rd ed. Boca Raton, Fla: CRC Press Inc, 2018;90136.

    • Search Google Scholar
    • Export Citation
  • 25.

    Gurvitch AM. Rhythmic bursts in the medullary reticular formation and their connection with agonal respiration during hypoxia and the post-hypoxic period. Electroencephalogr Clin Neurophysiol 1966;21:355364.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 26.

    Rea TD. Agonal respirations during cardiac arrest. Curr Opin Crit Care 2005;11:188191.

  • 27.

    Coulibaly B, Piercecchi-Marti MD, Bartoli C, et al.. Lethal injection of potassium chloride: first description of the pathological appearance of organs. J Appl Toxicol 2010;30:378380.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 28.

    Wetherton AR, Corey TS, Buchino JJ, et al.. Fatal intravenous injection of potassium in hospitalized patients. Am J Forensic Med Pathol 2003;24:128131.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 29.

    Aleman M, Davis E, Knych H, et al.. Drug residues after intravenous anesthesia and intrathecal lidocaine hydrochloride euthanasia in horses. J Vet Intern Med 2016;30:13221326.

    • Crossref
    • Search Google Scholar
    • Export Citation

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Use of potassium chloride for low-residue euthanasia of anesthetized California sea lions (Zalophus californianus) and northern elephant seals (Mirounga angustirostris) with life-threatening injury or disease

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  • 1 From The Marine Mammal Center, Sausalito, CA 94965.

Abstract

OBJECTIVE

To demonstrate the efficacy of potassium chloride (KCl) for low-residue euthanasia of anesthetized pinnipeds in field settings for which carcass retrieval for disposal is not feasible.

ANIMALS

Stranded, free-ranging California sea lions (CSLs; Zalophus californianus; n = 17) and northern elephant seals (NESs; Mirounga angustirostris; 6) with life-threatening injury or disease between May and August 2020.

PROCEDURES

Each animal was anesthetized and then received a lethal dose of KCl solution administered by IV or intracardiac injection. The effective KCl dose; durations to cardiac arrest, respiratory arrest, and pupil dilation; and presence or absence of agonal breaths, muscle fasciculations, or skeletal movements were recorded.

RESULTS

Mean effective dose of KCl was 207.4 mg/kg (94.3 mg/lb) for the 17 CSLs and 209.1 mg/kg (95.0 mg/lb) for 5 of 6 NESs (1 outlier NES was excluded). The range in duration from the beginning of KCl injection to cardiac arrest was 0 to 6 minutes, to pupil dilation was 0 to 5 minutes, and to respiratory arrest was 0 to 5 minutes. Muscle fasciculations, skeletal movements, and agonal breaths were observed in both species during and after KCl administration.

CONCLUSIONS AND CLINICAL RELEVANCE

The use of KCl provides an effective, low-residue method of euthanasia in anesthetized CSLs and NESs. Our recommended dose for these species is 250 mg KCl/kg (113.6 mg KCl/lb) delivered by intracardiac injection. Compared with euthanasia by barbiturate overdose, the use of KCl reduces the potential for secondary intoxication of scavengers and is appropriate in field scenarios in which the carcass cannot be retrieved for disposal. (J Am Vet Med Assoc 2021;259:197–201)

Abstract

OBJECTIVE

To demonstrate the efficacy of potassium chloride (KCl) for low-residue euthanasia of anesthetized pinnipeds in field settings for which carcass retrieval for disposal is not feasible.

ANIMALS

Stranded, free-ranging California sea lions (CSLs; Zalophus californianus; n = 17) and northern elephant seals (NESs; Mirounga angustirostris; 6) with life-threatening injury or disease between May and August 2020.

PROCEDURES

Each animal was anesthetized and then received a lethal dose of KCl solution administered by IV or intracardiac injection. The effective KCl dose; durations to cardiac arrest, respiratory arrest, and pupil dilation; and presence or absence of agonal breaths, muscle fasciculations, or skeletal movements were recorded.

RESULTS

Mean effective dose of KCl was 207.4 mg/kg (94.3 mg/lb) for the 17 CSLs and 209.1 mg/kg (95.0 mg/lb) for 5 of 6 NESs (1 outlier NES was excluded). The range in duration from the beginning of KCl injection to cardiac arrest was 0 to 6 minutes, to pupil dilation was 0 to 5 minutes, and to respiratory arrest was 0 to 5 minutes. Muscle fasciculations, skeletal movements, and agonal breaths were observed in both species during and after KCl administration.

CONCLUSIONS AND CLINICAL RELEVANCE

The use of KCl provides an effective, low-residue method of euthanasia in anesthetized CSLs and NESs. Our recommended dose for these species is 250 mg KCl/kg (113.6 mg KCl/lb) delivered by intracardiac injection. Compared with euthanasia by barbiturate overdose, the use of KCl reduces the potential for secondary intoxication of scavengers and is appropriate in field scenarios in which the carcass cannot be retrieved for disposal. (J Am Vet Med Assoc 2021;259:197–201)

Supplementary Materials

    • Supplementary Table S1 (PDF 162 KB)
    • Supplementary Table S1 (PDF 169 KB)

Contributor Notes

Address correspondence to Dr. Whitmer (emily.whitmer@gmail.com).