An analysis of 48,570 cardiac cycles revealed that monitoring stroke volume change via carotid Doppler might support the diagnosis and management of evolving hypovolemia

Flosonics Medical recently announced a study published in the British Journal of Anaesthesia in which Dr. Jon-Emile S. Kenny and colleagues evaluated the correlation between carotid Doppler ultrasonography and stroke volume during simulated hypovolemia and volume resuscitation.

Using the company’s lightweight, wireless, continuous wave Doppler ultrasound patch, the researchers studied changing metrics from the carotid Doppler pulse during a well-validated model of human haemorrhage: lower body negative pressure.

The researchers found that changing carotid Doppler pulse and stroke volume demonstrated a strong, positive linear association following an analysis of 48,570 cardiac cycles.

This is the largest data set correlating stroke volume change with the common carotid Doppler pulse to the investigators’ knowledge.

For this study, the researchers recruited 11 healthy adult volunteers with no cardiovascular history in a physiology lab at the Mayo Clinic.

They found that changing stroke volume correlated with various carotid Doppler measures, including an 18% change in maximum velocity time integral (VTI) and a 4.3% change in carotid corrected flow time.

The investigators concluded: “The strength of this correspondence is the large number of cardiac cycles captured and analysed by the wearable Doppler device as compared with the limited beats sampled by handheld Doppler devices in clinical studies.”

These findings suggest that monitoring stroke volume change via carotid Doppler might support the diagnosis and management of evolving hypovolemia.