The few literature citations involving blood pressure (BP) measurements in elephants have utilized direct arterial measurement of anesthetized or stationary conditioned animals.2-5
This project was expanded from an initial investigation comparing cited direct arterial measurements to indirect oscillometric BP measurement of systolic, diastolic, mean arterial pressure (MAP), and heart rate (HR) in four African elephants6 to data collection from 22 captive African elephants, 32 captive Asian elephants, and 30 captive working Asian elephants in Nepal. Blood pressure measurements were obtained in elephants ranging in age from 1 to 72 years old.
A standard occlusive BP cuff and unit (Cardell™, CAS Medical Systems, Inc. Branford, Connecticut 06405 USA) was utilized. The width of the cuff should approximate 40% the circumference of the tail of the elephant, in accordance with general recommendations for obtaining BP measurements in domestic animals.1 Cuff placement was at the distal extent of the caudal tail fold. Five sets of BPs, heart rates, and respiratory rates were obtained on three different occasions in each elephant, for a total of 1,260 readings.
Interpretation of initial results obtained indicate that infant animals have higher HRs and lower BPs, whereas adult animals of both species have lower HRs and higher BP readings. In addition, semi-wild Asian elephants appear to have overall lower BPs than their captive counterparts.
Use of an indirect oscillometric measuring device for obtaining BP measurement in elephants may prove to be an easily applied ancillary diagnostic tool when evaluating cardiovascular parameters without the need for sedation or immobilization.
The authors appreciate the contributions and access to elephants at the Kansas City Zoo, Houston Zoo, Indianapolis Zoo, Riddles Elephant Sanctuary, Dickerson Park Zoo, Ringling’s Center for Elephant Conservation, and Feld Entertainment. Special thanks to Dennis Schmitt, Susan Mikota, and the Nepal Government for coordinating access to elephants as well.
1. Binns, S., Sisson, D.A., Buoscio, and D.J. Scheffer. 1995. Doppler ultrasonic, oscillometric, sphygmomanometric, and photoplethysmographic techniques for noninvasive blood pressure measurement in anesthetized cats. J. Vet. Intern. Med. 9:405–414.
2. Honeyman, V.L., G.R. Pettifer, and D.H. Dyson. 1992. Arterial blood pressure and blood gas values in normal standing and laterally recumbent African (Loxodonta africana) and Asian (Elephas maximus) elephants. J. Zoo Wildl. Med. 23:205–210.
3. Jacobson, E.R., D.J. Heard, R. Caligiuri, and G.V. Kollias. 1987. Physiologic effects of etorphine and carfentanil in African elephants. Proc. 1st Intl. Conf. Zool. Avian Med. Pp. 525–527.
4. Jacobson, E.R., G.V. Kollias, D.J. Heard, and R. Caligiuri. 1988. Immobilization of African elephants with carfentanil and antagonism with nalmefene and diprenorphine. J. Zoo Anim. Med. 19:1–7.
5. Kock, R.A., P. Morkel, and M.D. Kock. 1993. Current immobilization procedures in elephants. In: M.E. Fowler, and R.E. Miller (eds.). Zoo and Wild Animal Medicine Current Therapy 3. W.B. Saunders Co., Philadelphia, Pennsylvania Pp. 436–441.
6. Suedmeyer, W.K., D. Fine. 2006. Indirect oscillometric blood pressure measurement in four African elephants (Loxodonta africana). Proc. Ann. Conf. Am. Assoc. Zoo Veterinarians. Tampa, Fl. Pp. 170–171.