Computerized Acoustic Swallowing Evaluation

In this study, the investigators will use commercially available electronic stethoscope to assess dysphagia in patients who have recently experienced a stroke. The Eko Core electronic stethoscope is approved by the Food and Drug Agency (FDA) is currently available for use in the health care context.

Phase I

In the first phase of this study the investigators will try to establish the electronic stethoscope's measurements for normal swallowing patterns. The investigators will recruit healthy controls and auscultate for swallowing sounds at three locations: in the anterolateral section of the neck, in the posterior section of the neck, and in the superior sternum as illustrated in Figure 1. After the sensors are placed, participants will be asked to perform the following tests:

• Dry Swallow - ask participant to swallow their saliva
• Ask participant to swallow 1 teaspoon of water
• Ask participant to swallow 3 ounces of water (continuous)
• Ask participant to swallow one teaspoon of applesauce
• Ask participant to chew one cracker Healthy subjects will be recruited by advertisement using a flyer. Interested individuals will be able contact the study coordinator by email or phone. Subsequently, the participants will present for consenting and testing at the CSMC rehabilitation gym (North Tower 7215) or Pacific Theaters Building (116 N. Robertson) at a mutually agreed time.

The results of these tests will be used to determine the electronic stethoscope's measurements for a normal swallowing pattern.

Additionally, the investigators will determine optimal sensor location by measuring the quality of the recordings obtained in each location, and getting participant input with regarding their preferred sensor location. Signal quality will be determined by observing the loudness of the swallowing signal relative to the loudness of background noises (heartbeat, pulse, etc.) in each of the three locations.

Phase II As part of their standard of care, all stroke patients at CSMC undergo a swallowing screen by the nursing staff at bedside. If a patient fails the bedside screen, a referral is made to the physician for a clinical swallowing evaluation by a swallowing therapist. If the patient fails the clinical swallowing evaluation, the referral is made to the physician for an instrumental swallowing evaluation which is often the videofluoroscopy swallowing study. At bedside, the electronic stethoscope will be used to monitor the patients' pharyngeal acoustic signals while they undergo swallowing evaluations monitored by members of the research team.

During Phase II all subjects will undergo evaluation by the electronic stethoscope. Regarding VSS, it is entirely dependent upon the managing medical team and the physician.

The investigators anticipate that a number of patients will undergo VSS. If VSS is required, the order and timing will be determined by the medical team. Given the dynamic nature of the acute inpatient setting, details such as timing of VSS cannot be anticipated.

Potential participants will be identified through the daily stroke list on CS-Link, which is reviewed by the investigators who have access to this list as part of routine daily operations. The investigator has access to the patient list as part of quality oversight. Per request for waiver of consent/authorization, patients will be selected from this list based on inclusion/exclusion criteria. Subsequently, the treating physician will be contacted for approval to recruit the patient. Once approval is given, the investigator will then visit the patient and ask if he or she is willing to participate. The investigator will only consent patients that are able to communicate clear understanding of the study, by demonstrating that they understand purpose, procedure, risks and benefits of the study. If the patient cannot understand the purpose of the study, risks, and benefits they will not be consented.

Eligible patients will be approached by a member of the research team who will discuss the study in detail with them and obtain consent.

Once consent is obtained, the electronic stethoscope will be placed on the location found in Phase I to be optimal, and the patient will be asked to perform the following tests at bedside and during the videofluoroscopy swallowing study:

• Dry Swallow-Ask patient to swallow their saliva
• Ask patient to swallow 1 teaspoon of water
• Ask patient to swallow 3 ounces of water (continuous)
• Ask patient to swallow one teaspoon of applesauce
• Ask patient to chew one cracker

The following outcomes will be measured in both evaluations:

• Timing of swallow onset (timing of hyoid elevation)
• Duration of pharyngeal phase of swallow
• Timing of esophageal phase onset
• Duration of esophageal phase of swallow
• Coughing (Yes/No)
• Throat clearing (Yes/No)
• Pharyngeal pooling (Yes/No)
• Spontaneous multiple swallows (more than one) to clear bolus (Yes/No)

The investigator will compare the data obtained using videofluoroscopy swallowing study with the signals recorded with the electronic stethoscope to determine whether the patterns detected by electronic stethoscope concur with those obtained via the videofluoroscopy swallowing study. Additionally, the investigator will compare the results to similar tests performed by nurses and swallowing therapists.

Lastly, the investigators will compare the data obtained by the electronic stethoscope from the healthy controls in Phase I with the data obtained from the stroke patients in Phase II, and the investigators will try to determine whether the signals recorded can differentiate normal from abnormal swallowing patterns.

Patients will not be compensated for their participation in this study.