HEART RATE and INDIRECT BLOOD PRESSURE RESPONSES to FOUR DIFFERENT FIELD ANESTHETIC PROTOCOLS in WILD-BORN CAPTIVE CHIMPANZEES (PAN TROGLODYTES)

Limited data are available on hemodynamic responses to anesthetic protocols in wild-born chimpanzees (Pan troglodytes). Accordingly, this study characterized the heart rate (HR) and blood pressure responses to four anesthetic protocols in 176 clinically healthy, wild-born chimpanzees undergoing routine health assessments. Animals were anesthetized with medetomidine-ketamine (MK) (n = 101), tiletamine-zolazepam (TZ) (n = 30), tiletamine-zolazepam-medetomidine (TZM) (n = 24), or medetomidine-ketamine (maintained with isoflurane) (MKI) (n = 21). During each procedure, HR, systolic blood pressure (SBP), and diastolic blood pressure (DBP) were regularly recorded. Data were grouped according to anesthetic protocol, and mean HR, SBP, and DBP were calculated. Differences between mean HR, SBP, and DBP for each anesthetic protocol were assessed using the Kruskall-Wallis test and a Dunn multiple comparisons post hoc analysis. To assess the hemodynamic time course response to each anesthetic protocol, group mean data (±95% confidence interval CI) were plotted against time postanesthetic induction. Mean HR (beats/min CI) was significantly higher in TZ (86 80-92) compared to MKI (69 61-78) and MK (62 60-64) and in TZM (73 68-78) compared to MK. The average SBP and DBP values (mm Hg CI) were significantly higher in MK (130 126-134 and 94 91-97) compared to TZ (104 96-112 and 58 53-93) and MKI (113 103-123 and 78 69-87) and in TZM (128 120-135 and 88 83-93) compared to TZ. Time course data were markedly different between protocols, with MKI showing the greatest decline over time. Both the anesthetic protocol adopted and the timing of measurement after injection influence hemodynamic recordings in wild-born chimpanzees and need to be considered when monitoring or assessing cardiovascular health.