The ideal place to take reptiles’ pulse

Photo: Noël Heaney/Cornell University

Taylor Lashlee (left), an intern at Cornell University, and Nicola Di Girolamo, DMV, PhD, DECZM (Herp), DACZM, DACVPM (right), use a new method to measure the pulse rate of a bearded dragon.

Researchers from Cornell University’s College of Veterinary Medicine in Ithaca, New York, have discovered an easy-to-reach spot on the back of reptiles’ head where pulse rate can consistently be measured. The pulse rate can be recorded using an ultrasonic Doppler flow detector, and corresponds with heart rate, allowing for more complete cardiovascular evaluations. The researchers found the pulse in the same place on other species of reptiles, including leopard geckos, turtles, tortoises, and snakes.¹

Photo: Nicola Di Girolamo/Cornell University

Researchers measure the pulse rate of a ball python

In the past, measuring the pulse rate of reptiles has been a difficult process. Stethoscopes are not a reliable instrument, as scales interfere with sound transmission, and scared tortoises and turtles tend to hide behind their legs, hiding their hearts. In pythons, specifically, there is a well-established location to obtain their heart rate, but not their pulse rate.¹

Investigators set out to establish a standardized technique to obtain reptiles’ pulse rate. They obtained temporoorbital pulse rates in 40 healthy ball pythons (Python regius), weighing between 0.05 kg and 2.2 kg, to determine whether their measurements agreed with heart rates. The pulse rates were obtained on the dorsal aspect of the pythons’ heads, at the level of the temporoorbital artery.²

The research group was successful in their study, obtaining pulse rates and heart rates for all 40 of the snakes. The median pulse rate and heart rates were both 60 bpm, and both had ranges from 48 bpm to 88 bpm. The mean difference between pulse rate and heart rate was 1.2 beats, and the rates were synchronous when measured simultaneously.²

Photo: Noël Heaney/Cornell University

Investigators measure the pulse rate of a bearded dragon

The study was initiated by a bearded dragon with an aneurysm, which caused the temporoorbital artery in the back of its head to become enlarged. It was in this location that they found a pulse. “You could put the Doppler there, and you would hear the pulse rate very well,” Nicola Di Girolamo, DMV, PhD, DECZM (Herp), DACZM, DACVPM, associate professor of exotic animal medicine corresponding author of the study, said in a Cornell Chronicle article.¹ “We thought it was only happening because the vessel was so distended, but then we checked another bearded dragon kind of randomly in the same area, and we realized that it had the pulse there.”

The discovery of this method is a significant step forward in exotic animal medicine. With this new technique, veterinarians can treat reptiles in a way that is significantly less stressful for the animal, which results in better treatment overall.

References

1. Hartigan H. Researchers find a place to take a python’s pulse. Cornell Chronicle. September 5, 2024. Accessed September 6, 2024. https://news.cornell.edu/stories/2024/09/researchers-find-place-take-pythons-pulse
2. Ito M., Levitskiy A., Di Girolamo N. Temporoorbital pulse rate can be obtained in ball pythons (Python regius) of any size and age and agrees with heart rate. Vet Rec. 2024. https://doi.org/10.1002/vetr.4596