Environmental and the Athlete

Presentation subtitle

Heat Illness Frostbite Altitude Illness Month Day, Year Thomas Moran MD Northshore University Health System Clinician educator, University of Chicago Introduction

Chicago Marathon >41,000 runners – 2006 (36° start,48° high with slight rain) – 2007 (88° high, 80% humidity)

American Birkebeiner >10,000 skiers – 2011 (-6° start) – Last decade, 6 starts under 10°

Leadville 100 >300 runners – Start 10,400 ft, peak >12,500 ft Objectives

Heat illness -Recognize of Heat related emergencie Winter Athlete Heat Illness

Heat Exhaustion – Sign of systemic vascular strain in body’s attempt to maintain temp.

Heat Stroke – Continuation of above but with evidence of altered mental status.

Heat Illness

Doug Schmied Fran Crippen Offensive guard Swimmer IL Wesleyan Gold medalist 2005 Oct 2010 Steve Bechler Luke Roach Pitcher Chicago Marathon Baltimore Orioles Mile 26 Feb 2003 Oct 2001 Exertional heat illness

Factors contributing: 1) Increased internal production Physical activity Pharmacologic agents Febrile illness

2) Increased External heat gain High ambient temperature

3) Decreased ability to disperse heat Humidity Protective gear Pharmacologic agents Heat Illness

Heat Exhaustion – Signs of systemic vascular strain in body’s attempt to maintain basal temperature. –Temp 97-104°

Heat Stroke –Same as above but w/ end organ damage. –Temp >104°

*AMSAlso consider Hyponatremia (AMS with normal temp) Heat Illness

Diagnosis -Heightened level of suspicion

-Temperature Rectal. (Thermometers inaccurate in exercising individuals)

Treatment -Cool now Cooling Modalities Cold Water Immersion Duration of cooling 109.4 F

107.6 F

Fan 105.8 F Cold towels to major vessels CWI 104 F Treatment

Treatment Take action Rapid cooling Normal mental status, temp <104 – PO liquid, shade, wet towels AMS and/or temp >104 – Immediate ice bath immersion – Remove at 102° (cool 1° e 3min) Heat Illness

Doug Schmied Fran Crippen Offensive guard Swimmer IL Wesleyan Gold medalist 2005 Oct 2010 Steve Bechler Luke Roach Pitcher Chicago Marathon Baltimore Orioles Mile 26 Feb 2003 Oct 2001 Heat Illness

Prevention Acclimatization Clothing Hydration ( loss, 1L/hr) Activity planning reduction Acclimation

Within days to 1st week: 1. Heart rate decreases 2. Changes in and core temp 3. Increased sweat rate -Changes in sweat composition 4. Increased work capacity

• Faster response in highly trained individuals • Optimal acclimation time 10-14 days • Decay rate is slower then acclimatation (4 weeks) Heat acclimation and performance?

Power output during a 43.4- km cycling TT in TTC (plain line) TTH-1 (long dashed line), TTH-2 (short dashed line), TTH-3 (dotted line)

RACINAIS, S; PÉRIARD, J.; KARLSEN, A; NYBO, L. Effect of Heat and Heat Acclimatization on Cycling Time Trial Performance and Pacing. Medicine & Science in Sports & Exercise47(3):601-606, March 2015. Clothing

• Sun protection • Light color • Wicking

• Precooling strategies? Can precooling improve performance? Medications

Too much heat production -SSRIs -MAOIs -amphetamines -ephedra

Inability to dissipate -anticholinergics -antihistamines -clonidine (Klonapin) Hydration

Hydration Status • Plasma osmolality and urine specific gravity. • Euhydrated if daily body mass changes remain <1% for several days, plasma osmolality is <290 mmol/kg and urine specific gravity is <1.020. General methods To Establish Baseline • Measure post-void nude body mass in the morning on consecutive days after consuming 1–2 L of fluid the prior evening.

• Urine color Wet-Bulb Globe Temperature

-Temperature -wind speed -humidity -radiation Marathon Experience

• >40,000 runners • Medical volunteers – RN, PT, MD/DO, podiatry, massage therapist… • 2-8+ hrs athletes are exposed to environment. • Drastic weather changes year to year. Environmental Injuries: The Winter Athlete

Thomas Moran MD Northshore University Health System Clinician educator, University of Chicago Cold

Hypothermia – Core body temperature below 95°F (35°C).

Frostbite – Direct freezing of tissue when skin temperature drops below 32°F (0°C)

“Man in the cold is not necessarily a cold man.” -David Bass 1958 Physiologic response to Cold Peripheral -First response to cold exposure. -Once Skin temp below 95°F. -Insulating effect.

Increased metabolic heat production - Shivering, peaks with skin temp 68° F and core of 95°. -Increases basal metabolic rate up to 5x baseline.

Hypothermia

Definition: Core temperature less than 95°

Develops when total body heat loss exceeds physiologic heat production. Hypothermia Diagnosis -Accurate core temp -Symptom recognition:

>90° Early symptoms Feeling cold, shivering, social withdrawal Moderate Confusion, sleepiness, slurred 82-90° hypothermia speech… *Irritable cardiac tissue <82° Severe Eventual loss of consciousness, loss of reflexes… *Arrhythmias common J-wave Predisposing Risk Factors

Castellani, John W et al. Prevention of Cold Injuries During Exercise. Medicine & Science in Sports & Exercise. 38(11):2012-2029, November 2006. Hypothermia

Temp Features Treatment/Rewarming 95° Max shivering Passive external 91° Ataxia, apathy Passive external 90° Stupor, shivering ceases, Arrhythmias Active external <82° Decreased Vfib threshold Active core

Treatment Mild: Remove cold, wet clothing. Shelter Allow shivering Avoid massage Passive external (warm blankets, PO warm liquid) Moderate to Severe: Active external (hot water bottles, heating pads, etc) Active core (D5NS at 104°-108°)

*Afterdrop Phenomenon

Frostbite

Localized cold injury produced by freezing of tissue.

Sites typically affected are furthest from core. – Hands, feet, face, nose and

Also from direct contact. – Metal, petroleum products… Frostbite

Sensation at varying skin temperatures:

82° Cooling sensation  68° Pain  50° Numbness

Vasoconstriction

Cold exposure Tissue freezing Cell wall damage

Inflammation F2a, thromboxane Risk Factors

Castellani, John W et al. Prevention of Cold Injuries During Exercise. Medicine & Science in Sports & Exercise. 38(11):2012-2029, November 2006. Frostbite Superficial- Normal skin color, large (serous or white), intact pinprick, skin indents with pressure. Deep- Nonblanching cyanosis, dark blisters (sanguineous), Skin “wooden to touch.” Frostbite

Prognosis: • Vascular studies • Watchful waiting. ultimate viability not determined until 22- 45days.

Treatment: • Do not rewarm if risk of refreezing! • Do not massage!

• Rapid submersion….rewarm affected parts in H2O (104°-108°) • Debride clear blisters, Leave blood filled Frostbite presentation Case

• 19yo college XC runner following up for tibia stress reaction • Week previous, had increased mileage – Went for 13mi run in bitter cold • Next day – on dorsum of great – Attributed to runners toe • 1 week later… Case

• Protected area • Activity modification • Wait and see • 10 days after initial eval… Cold Injury - Prevention

*Avoid cold wet exposure*

Choice clothing “3L” Loose Layered Lightweight Wind/waterproof outer layer

Avoid emollients on skin

Thorleifsson, A., and H. C. Wulf. Emollients and the response of facial skin to a cold environment. Br. J. Dermatol. 148: 1149-52, 2003 Cold injury – Prevention

NOAA.gov

Altitude affects

• Altitude environment – Cold – Low Humidity – UV radiation – Decreased air pressure

• Linear correlation between barometric pressure and available oxygen. -760 mmHg Sea level -520 mmHg 10,000 -380 mmHg 18,000 ft University of Colorado High Altitude Illness

AMS HACE HAPE Acute Mountain High-altitude High- cerebral edema pulmonary edema

-Rapid ascent past 8,000ft -Headache is usually initial symptom of illness -Descent is definitive therapy High Altitude Illness AMS HACE HAPE Acute Mountain High-altitude High-altitude Sickness cerebral edema pulmonary edema

-Most common illness by travelers to altitude -Symptoms 6-12 hrs after ascent to >8,000ft. Headache with: nausea, fatigue, dizziness or insomnia -No validated physiologic markers High Altitude Illness

AMS HACE HAPE Acute Mountain High-altitude High-altitude Sickness cerebral edema pulmonary edema

Lake Louse Questionnaire 1) Headache 2) Additional symptom 3) Total score >3 High Altitude Illness AMS HACE HAPE Acute Mountain High-altitude High-altitude Sickness cerebral edema pulmonary edema

CNS symptoms ataxia, altered consciousness, confusion, drowsiness, stupor and coma Underlying mechanism is unclear. High Altitude Illness AMS HACE HAPE Acute Mountain High-altitude High-altitude Sickness cerebral edema pulmonary edema

MCC of altitude related death. Typically presents 48-96hrs after arrival above 8,000ft AMS with classic signs of pulmonary edema (wet cough, dyspnea at rest, weakness and orthopnea) Etiology for disease: Hypoxia leads to exaggerated hypoxic pulmonary vasoconstriction. Increased PA pressure Subsequent transudative leak. Treatment Acute Mountain Sickness - assent and rest. -Descend/recompression if no improvement -Low flow oxygen -Carbonic anhydrase inhibitor Acetazolamide (125-250mg BID) HACE & HAPE -Immediate descent, Oxygen -Specific Adjuvant medications HACE-Dexamethasone 8mg once, 4mg QID HAPE-Nifedipine 30mg BID as prophylaxis? High Altitude Illness Prevention

Begin exertion below 8,000ft

2-3 nights 8-10,000ft then ascend

Beyond 10,000ft, ascend 1500 ft before another nights rest

Avoid alcohol and opiates

Avoid dehydration and hypothermia

Acetazolamide 125-250mg BID Dexamethasone 4mg PO BID Proposed prevention meds: -Ibuprofen 600mg TID, -Sildenafil, Role of Nitric Oxide

-Observed increases in NO during acclimatization. -PDE-5 as treatment and prophylaxis -Adjuvant treatment in cases with HAPE -Prophylaxis SE profile outweighs protective benefit.

Bates MG et al. Sildenafil citrate for the prevention of high altitude hypoxic pulmonary hypertension. High Alt Med Biol.2011; 12 (3): 207-14. Altitude

• Allow adequate acclimatization above 8000ft. – Ascend less than 1500 ft per day. • Identify altitude related illness • HAPE and HACE are emergencies! • Definitive treatment is descent. • Prophylaxis includes slow assent and if necessary Carbonic Anhydrase inhibitors. Thank You

Bartsch P, Swenson ER. Acute high-altitude illnesses. N Engl J Med. 2013 Oct 24;369(17):1666–7

Castellani J, Young A, Ducharme M et al. Prevention of Cold Injuries during Exercise. Medicine and Science in Sports and Exercise. 2006; 06: 2012-29.

Grieve A, Davis P, Dhillon S, Richards P, Hillebrandt D, Imray C. A clinical review of the management of frostbite. J R Army Med Corps. 2011: 157(1):73-8.

Derby R, DeWeber K. The Athlete and High Altitude. Current Sports Medicine Reports. 2010: 9 (2): 79-85.

O’Conner F, et al. ACSM Sports medicine: A Comprehensive Review. 2010.