A Study of the Feasibility of Prehospital Remote Ischemic Conditioning

A Pilot Study of the Feasibility of Prehospital Delivery of Remote Ischemic Conditioning by Emergency Medical Services in Chest Pain Patients

Prospective, single center, single arm pilot study evaluating the feasibility of delivering remote ischemic conditioning (RIC) by emergency medical services (EMS) in the prehospital setting. Eligible patients will have chest pain or anginal equivalent symptoms and require ground ambulance transport to the hospital. All subjects will undergo the standard RIC procedure (i.e., up to four cycles of alternating 5-min inflation and 5-min deflation) with the autoRIC® device (CellAegis Devices, Inc., Toronto, Ontario). The primary objective is to evaluate the number of cycles of RIC completed in patients having the procedure initiated by EMS in the prehospital setting.

This single-arm, open-label pilot study will evaluate the feasibility of delivering remote ischemic conditioning (RIC) by emergency medical services (EMS) in the prehospital setting. Eligible patients will be at least 18 years of age, and require ground ambulance transport to the hospital. Patients suspected of ST-elevation myocardial infarction (STEMI) based on the prehospital electrocardiogram and thus requiring urgent intervention in the cardiac catheterization lab will be excluded. All subjects will undergo the standard RIC procedure (i.e., up to four cycles of alternating 5-min inflation and 5-min deflation) with the autoRIC® device (CellAegis Devices, Inc.). The automated procedure will be initiated by paramedics during ambulance transport, and the RIC cycles will continue through emergency department (ED) arrival and stay for a total of 40 minutes. The primary objective of this pilot study is to examine the duration of RIC administered in patients having the procedure initiated in the prehospital setting. The investigators hypothesize four cycles of RIC will be completed in at least 80% of patients having the procedure initiated. Secondary objectives are to assess enrollment rates and protocol implementation; paramedic acceptability of protocol; and patient tolerability of RIC.

Prospective, single center, single arm pilot study evaluating the feasibility of delivering remote ischemic conditioning by emergency medical services during ground ambulance transport of patients experiencing chest pain or anginal equivalent symptom

RIC procedure (i.e., four cycles of alternating 5-min inflation and 5-min deflation) administered by the autoRIC® device

The autoRIC® automatically delivers four RIC cycles of five minutes of pressure at 200 mm Hg followed by five minutes of no pressure for a total 40-min treatment period

A completed RIC cycle without interruption is defined as 5 minutes inflation followed by 5 minutes deflation for a total of 10 minutes.

Times will be reported for on-scene arrival, patient transport, screening, recruitment, and RIC initiation to assess efficiency with which the study protocol was implemented. Screening, recruitment and RIC initiation times are overlapping with transport time.

Qualitative themes related to implementation of the study protocol will be derived from semi-structured interviews with study paramedics.

Percent of Participants Experiencing Anticipated Adverse Events Including RIC Discontinuation Due to Discomfort

Anticipated adverse events related to RIC including minor arm discomfort, temporary discoloration of the arm or hand, and minor skin bruising or abrasions on the upper arm will be collected via in-person and telephone evaluation.

Qualitative themes related to the RIC procedure will be derived from semi-structured interviews with subjects.

Inclusion Criteria: Requiring 9-1-1 response to scene At least 18 years of age Experiencing non-traumatic chest pain or anginal equivalent symptom Not meeting EMS criteria for a suspected STEMI based on prehospital ECG Systolic blood pressure (SBP) between 100-180 mgm Hg Designated for ambulance transport to University of North Carolina Medical Center (Chapel Hill, NC) Capable of providing informed consent Exclusion Criteria: Unconscious or otherwise in critical condition Lacking capacity to consent to the study Non-English speaking Pre-existing condition precluding blood pressure check or use of the autoRIC® at the discretion of the provider or listed here: Paresis of upper limb Pre-existing traumatic injury to arm Presence of an arteriovenous shunt for dialysis Prior mastectomy Existing peripheral inserted central catheter line Arm edema or other indication of upper extremity thrombosis Serial ECG evidence of evolving STEMI

The researchers have no plans to make individual participant data available. Due to this study's small size and single site, individual level data will not be shared to protect the privacy of subjects and maintain the confidentiality of data. Aggregated data and results on primary and secondary outcomes will be reported on this site and published in the scientific literature.

Patel MD, Platts-Mills TF, Grover JM, Thomas SM, Rossi JS. Feasibility of prehospital delivery of remote ischemic conditioning by emergency medical services in chest pain patients: protocol for a pilot study. Pilot Feasibility Stud. 2019 Mar 13;5:42. doi: 10.1186/s40814-019-0431-8. eCollection 2019.