Thermoregulation

 

John P. Handrakis, PT, DPT, EdD, NCS
Associate Professor,
School of Health Professions,
New York Institute of Technology

Research Health Scientist Specialist,
James J. Peters VA Medical Center
(718) 584-9000 x5439
john.handrakis@va.gov

Dr. Handrakis’ interest in dysfunction and impairment of the body began when he worked as a physical fitness trainee before he had received any formal medical training. In 1978, he earned a baccalaureate in Science from Fordham University. After becoming a licensed physical therapist in New York and California, he earned his Master of Science degree in physical therapy from Columbia University’s College of Physicians and Surgeons and soon began working as a physical therapist at Rusk Rehabilitation Institute at New York University Medical Center. While gaining experience providing care for patients with various neurological conditions, he was working to obtain a second Master of Science degree in Exercise Physiology from Long Island University. After leaving Rusk in 1985, Dr. Handrakis had the opportunity to work in several out-patient orthopedic and sports medicine clinics.

In 2008, Dr. Handrakis received a doctoral degree in applied physiology from Columbia University. While earning his doctoral degree, he trained under the supervision of Dr. Jill M. Wecht, a nationally recognized authority in dysfunction of the cardiovascular autonomic nervous system after spinal cord injury. Dr. Handrakis joined the faculty of the New York Institute of Technology in the Doctoral Physical Therapy Program, and he also took a position as a Research Health Science Specialist in the Spinal Cord Damage Research Center. Two years later, in 2010, he earned a DPT degree from New York Institute of Technology (NYIT). Dr. Handrakis enjoys mentoring physical therapy students at NYIT and in the Spinal Cord Damage Research Center, where students from the program at NYIT assist in his research on thermoregulation performed in those with higher cord lesions.

With the opportunity to continue research at the Spinal Cord Damage Research Center as the Principal Investigator of the Thermoregulation Program, Dr. Handrakis continues to work to identify safe and effective interventions to maintain core body temperature and cognitive function under conditions of thermal stress in persons with spinal cord injury.

Program goals (Lay)
Having a core body temperature of 98.6°F is integral to health and wellbeing. The body unconsciously regulates its temperature, retaining body heat in the cooler environments and losing body heat in warmer environments. These autonomic (or “silent”) nervous system thermoregulatory actions are taken for granted in non-spinal cord injured individuals but are difficult or impossible to perform in those with a spinal cord injury. If core body temperature is reduced, brain function is adversely affected, in particular, the ability to reason clearly. Persons with a spinal cord injury cannot constrict or dilate blood vessels, sweat or shiver below the level of lesion. They also may not feel whether they are too hot or cold. As such, a person may risk overheating (e.g., hyperthermic) on a summer day, or in the winter, become sufficiently cold to reduce brain function (e.g., hypothermic).

Dr. Handrakis and his team use a temperature-isolation room with sophisticated equipment to study the effects of cool (64°F) or warm (95°F) temperatures on core body temperature regulation and swings in body temperature on brain function. Dr. Handrakis has been trying to better define the mechanisms that make those with paralysis less able to regulate their core temperature when under the two extremes of thermal stress. A drug that raises blood pressure by constricting blood vessels, midodrine, is being tested on patients to help them achieve and maintain a stable core temperature when exposed to cool environmental temperatures. Through his work, he hopes to help persons with spinal cord injury maintain a stable state of brain function in all temperature environments and seasons.

Program goals (Scientific)
Spinal cord injury (SCI) interrupts the ability to maintain an appropriate body temperature (thermoregulation) during exposure to a wide range of ambient temperatures. Dr Handrakis is studying the possibility that even limited exposure (i.e., less than 2 hours) to cool temperatures (64°F) can impair cognitive performance in persons with spinal cord injury.

Presently, Dr. Handrakis and his team are conducting two studies that are exploring the effects of either cool temperature (64°F: clinicaltrials.gov NCT02379156) or hot temperature (95°F: clinicaltrials.gov NCT02488824) exposure in persons with higher levels of spinal cord injury.  The impact of the thermal challenge on cognitive performance will be determined by rigorous cognitive function testing. The long-term objective of this work is to develop safe and effective interventions to improve the ability of those with spinal cord injury to appropriately regulate internal body temperature and optimize cognitive performance during activities of daily living.


 

Research

Relevant Publications

  1. Handrakis JP, Liu SA, Rosado-Rivera D, Krajewski M, Spungen A, Bang C, Swonger K, Bauman, WA. Effect of Mild Cold Exposure on Cognition in Persons with Tetraplegia. J Neurotrauma 2015;Epub ahead of print.

http://www.ncbi.nlm.nih.gov/pubmed/25531297

  1. Rosado-Rivera D, Radulovic M, Handrakis JP, Cirnigliaro CM, Jensen AM, Kirshblum S, Bauman WA, Wecht JM. Comparison of 24-hour cardiovascular and autonomic function in paraplegia, tetraplegia, and control groups: implications for cardiovascular risk. J Spinal Cord Med. 2011;34(4):395-403.

http://www.ncbi.nlm.nih.gov/pubmed/21903013

  1. Wecht JM, Rosado-Rivera D, Handrakis JP, Radulovic M, Bauman WA. Effects of midodrine hydrochloride on blood pressure and cerebral blood flow during orthostasis in persons with chronic tetraplegia. Arch Phys Med Rehabil. 2010 Sep;91(9):1429-35.

http://www.ncbi.nlm.nih.gov/pubmed/20801263

  1. Wecht JM, Weir JP, DeMeersman RE, Schilero GJ, Handrakis JP, LaFountaine MF, Cirnigliaro CM, Kirshblum SC, Bauman WA. Cold face test in persons with spinal cord injury: age versus inactivity. Clin Auton Res. 2009 Aug;19(4):221-9.

http://www.ncbi.nlm.nih.gov/pubmed/19418115

  1. Handrakis JP, DeMeersman RE, Rosado-Rivera D, LaFountaine MF, Spungen AM, Bauman WA, Wecht JM. Effect of hypotensive challenge on systemic hemodynamics and cerebral blood flow in persons with tetraplegia. Clin Auton Res. 2009 Feb;19(1):39-45.

http://www.ncbi.nlm.nih.gov/pubmed/18850311

Handrakis JP, Rosado-Rivera D, Singh K, Swonger K, Azarelo F, Lombard AT, Spungen AM, Kirshblum SC, Bauman WA. Self-reported Effects of Cold Temperature Exposure in Persons with Tetraplegia. J Spinal Cord Med; 2016, in Press

Handrakis JP, Liu SA, Krajewski M, Spungen AM, Bang C, Swonger K,Bauman WA. Effect of Mild Cold Exposure on Cognition in Persons with Tetraplegia. Journal of neurotrauma; 2015 Aug 1;32(15):1168-75

Jill M. Wecht, EdD, Michael F. La Fountaine, EdD, ATC, John P. Handrakis, PT, DPT, EdD, Christopher R. West, PhD, Aaron Phillips, PhD,  David S. Ditor, PhD, Hisham Sharif, PhD, William A. Bauman, MD, Andrei V. Krassioukov, MD, PhD. Autonomic Nervous System Dysfunction Following Spinal Cord Injury: Cardiovascular, Cerebrovascular and Thermoregulatory Effects. J Current Reports in Rehab Med; 2015 3(3):197-205


Additional Link(s) of Interest:

http://asia-spinalinjury.org/about/new-member-spotlight/