Abstract
Heart disease is considered one of the major causes of mortality in captive chimpanzees (Pan troglodytes).3,5 Hypertension is a significant risk factor in cardiovascular disease in humans and may contribute to cardiac disease in chimpanzees.1,3 Arterial blood pressure is also a fast and informative method of assessing cardiovascular function during anesthesia. Because blood pressure (BP) is typically measured under anesthesia in chimpanzees, it is paramount to determine baseline values for different anesthetic protocols. Fifty-three chimpanzees ranging from 1 to 37 years old were chemically immobilized with one of two different anesthetic combinations: tiletamine-zolazepam (TZ, average dose 10 mg/kg), n=23 or tiletamine-zolazepam-medetomidine (TZM, average dose TZ—2 mg/kg, M—0.030 mg/kg) n=30. Blood pressures were obtained over 70 minutes using a sphygmomanometer and stethoscope over the brachial artery. Systolic, diastolic blood pressures and heart rate (HR) results for the TZ group were 104.79±11.51 mm Hg, 58.47±11.57 mm Hg, and 86.08±7.49 beats per minute (BPM), respectively. For the TZM group, systolic, diastolic, and HR results were: 127.75±13.17 mm Hg, 87.89±12.22 mm Hg, and 72.71±5.01 BPM, respectively. Preliminary results indicate that adult chimpanzees immobilized with the TZ combination at Chimfunshi Wildlife Orphanage are within the normotensive category group.1 Higher systolic and diastolic BPs were observed on the TZM group, with the systolic BP still falling within the normotensive reference range but diastolic BP in the pre-hypertensive category.1 The higher BP observed in the medetomidine combination is consistent with findings in other great species when this drug has been utilized.2,4
Literature Cited
1. Ely JJ, T Zavaskis, ML Lammey, DR Lee. Blood pressure reference intervals for healthy adult chimpanzees (Pan troglodytes). J Med Primatol. 2011;40:171–180.
2. Horne WA, TM Norton, MR Loomis. Cardiopulmonary effects of medetomidine-ketamine-isoflurane anesthesia in the gorilla (Gorilla gorilla) and chimpanzee (Pan troglodytes). Proc Am Assoc Zoo Vet. 1997:140–142.
3. Lammey ML, GB Baskins, DR Lee, et al. Interstitial myocardial fibrosis in a captive chimpanzee (Pan troglodytes) population. Comp Med. 2008;58:389–394.
4. Napier JE, IB Kutinsky, DL Armstrong, et al. Evaluating echocardiogram and indirect blood pressure results in male western lowland gorillas (Gorilla gorilla gorilla) during three phases of an anesthetic protocol. J Zoo Wildl Med. 2013;44:875–881.
5. Seiler BM, EJ Dick, R Guardado-Mendoza, et al. Spontaneous heart disease in the adult chimpanzee (Pan troglodytes). J Med Primatol. 2009;38:51–58.