H.19 Return of spontaneous circulation

The role of cardiopulmonary resuscitation (CPR) is to physically take over for a dysfunctional heart until the heart is able to start beating again on its own. The moment the heart starts beating, referred to as the return of spontaneous circulation (ROSC), is the indicator that CPR can be stopped. The established approach to detecting ROSC is through the identification of a pulse, typically performed through manual palpation. These manual palpations occur during pauses of CPR, known as pulse checks. While pulse checks are necessary, it is critical that they be as short as possible to minimize the interruption of CPR and improve clinical outcomes. Point of care ultrasound (POCUS) is emerging as a superior, quicker, and more sensitive tool to determine ROSC in comparison to manual palpation. POCUS utilizes an ultrasound probe, that when placed directly on the artery can visually show if the artery is beating. POCUS pulse checks have been proven more rapidly identify ROSC, shortening the time off the chest, which in turn decreases morbidity and improves clinical outcomes (Badra et al. 2019). 

The current shortcoming of POCUS in CPR is its intrusive nature. In most emergency departments, large ultrasound machines are almost exclusively used during resuscitation efforts. These machines are bulky and take up precious space in the resuscitation room. The ultrasound probe itself is connected to the machine, creating a physical obstacle during CPR. Ideally, the probe should be on the artery throughout the resuscitation so a pulse can be constantly observed and quickly identified during pauses of CPR. Currently, this approach requires a dedicated team member to hold the probe in the proper location throughout CPR, rendering the member unable to perform other critical tasks and physically hindering other staff members from performing their duties.

The goal of this project is to design a solution that allows for constant, contactless pulse checks, addressing the intrusiveness of current POCUS use in CPR. The final design needs to be unobtrusive and securable at the appropriate anatomical location, allowing for a hands-free approach to identify ROSC. This would shorten the time necessary for pulse checks and allow for the full use of personnel present.

Note to students: 

-The clinician sponsoring this project recommended the approach to solve the problem to focus on a redesign of a POCUS sensor.  However, in this project, you are not necessarily limited to explore solutions related to a POCUS device.  

-Other solutions may include NIRS-based approaches for hemodynamic monitoring, or some other mechanism of action. You are invited to explore all possible alternative solutions beyond the ultrasound space

References:

1. 1) Kern KB, Hilwig RW, Berg RA, et al. Importance of continuous chest compressions during cardiopulmonary resuscitation: improved outcome during a simulated single lay-rescuer scenario. Circulation 2002;105:645-9. 
2. 2) Berg RA, Sanders AB, Kern KB, Hilwig RW, Heidenreich JW, Porter ME, et al. Adverse hemodynamic effects of interrupting chest compressions for rescue breathing during cardiopulmonary resuscitation for ventricular fibrillation cardiac arrest. Circulation. 2001;104(20):2465–70
3. 3) Badra K, Coutin A, Simard R, Pinto R, Lee JS, Chenkin J. The POCUS pulse check: A randomized controlled crossover study comparing pulse detection by palpation versus by point-of-care ultrasound. Resuscitation. 2019;139:17—23.