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Home , Barodontalgia, Barotrauma, Dysbarism, Hypothermia

Environmental Injuries

Co lin G . K aid e, MD , FACEP , FAAEM, UHM Associate Professor of Board-Certified Specialist in Specialist in Wound Care The Ohio State University Wexner Medical Center

The Most Dangerous Drug Combination… Accidental Testosterone and Alcohol!

The most likely victims…

Photo: Ralf Roletschek

1 Definition of Blizzard Hypothermia of Subnormal T° when the body is unable to generate sufficient heat to sustain normal functions Core < 95°F 1979 (35°C)

Most Important

95°F (35° C) Hyper/Goofy The body uses a Poikilothermic shell to maintain a Homeothermic core 90°F (32°C) Shivering Stops Maintains core T° w/in 1.8°F(1°C) 80°F (26. 5°C) Vfib, 65°F (18°C) Constant T° 96.896.8-- 100.4° F

2 Thermoregulation The 2 most important factors Only 3 Causes!

Shivering (10x increase)  Decreased Heat Production Initiated by low  Increased Heat Loss Warming the skin can abolish  Impaired Thermoregulation shivering! Peripheral Sequesters heat

Predisposing Predisposing Factors Factors Decreased Production Increased Loss –Endocrine problems Radiation Evaporation • Thyroid Conduction* • Adrenal Axis **

– *Depends on conducting material **Depends on wind velocity –Neuromuscular disease

3 Predisposing Systemic Responses CNS Factors T°< 90°F (34°C) Impaired Regulation Hyperactivity, excitability, recklessness CNS injury T°< 80°F (27°C) Hypothalamic injuries Loss of voluntary motion and Peripheral Injury T°< 75°F (24°C) Atherosclerosis Loss of corneal & oculocephalic reflexes Neuropathy Interfering Agents The patient can look dead!

Systemic Responses The Infamous Osborn Wave Cardiovascular A form of early repolarization

Above 90°F (32°C): Excitatory , Elevated “J” Point

Below 90°F (32°C): Inhibitory response Bradycardia at level of pacemaker cells Atrial and ventricular dysrhythmias “The Hypothermic Hump” Atrial Fib Vasodilatation

4 Systemic Responses Systemic Responses Pulmonary Renal

Initially is seen occurs early T°<90< 90°F(32F (32°C) RR can fall to 5 -10 Central hypervolemia ADH suppression Minute volume falls T°< 90°F (32°C): Kidney function proportional to metabolic rate declines

Systemic Responses Systemic Responses Hematologic Hematologic Platelet Issues Thrombocytopenia Platelet dysfunction

Cold can produce significant Coagulopathy bleeding Dysfunction Occurs by 2 mechanisms

5 Question? Question?

Do people Although bleeding occurs, the really take off measured PT and PTT are usually normal - Why does this happen? thiheir c loth es when freezing to ?

Image from Ponder High School

Cold Water Immersion- Cold Water Immersion Hmmm?

Heat loss in cold water is 20- 30 times that of air! Many additional factors come into play in cold water immersion!

Image from Chicago Tribune

6 Cold Water Death! January 13, 1982 Air Florida Flight 90

Death may occur in only 15 minutes but NOT from hypothermia

Cardiac dysrhythmias-“Sudden“Sudden Disappearance” abnormalities Gasp, Muscular dysfunction In water for 1 hour and 45 minutes before rescue!

News Story - Chicago Tribune

Hypothermia Effects Jimmy Tontlewicz • Video 1: Air Florida Flight 90 “A heroic story of survival” On Jan. 15, while sledding with his father, Jimmy plunged into the icy waters of Lake Michigan. When rescuers pulled him out, he had been submerged for at least 20 minutes and had no discernible heartbeat, or breathing. In Chicago last week doctors said Jimmy is progressing so well that they hope to

"Seconds from Disaster--The crash of Air Florida Flight 90 send him home this month. Video from National Geographic

7 Management and Rewarming of a H ypo therm ic P ati ent

News Story - Chicago Tribune

Emergency Medicine Dogma ...You’re already dead!

You’re not dead until you’re... Warm and dead

Unless...

Drawn by friend-Kestutis Boyev

8 Treatment Death! Do Primary/Secondary Survey

Still dead with T°> 32°C (90°F) Serum potassium > 10 Evaluate for other treatable conditions Documented and verified DNR orders!

College newspaper: Daily Illini

Rewarming Most Important Rule

If the core temperature is less than 90°F (32°C) and shivering has stopped, YOU MUST ADD HEAT to the core!

9 Rewarming is Additive Rewarming: Passive

Insulate and allow shivering to raise body temperature Appropriate for mild ++++++++ + + + + + + hypothermia Core Temperature > 32°C/90°F Healthy individuals

Rewarming:Active Rewarming: Core Rewarming Often VERY complicated to perform ADD HEAT! Supplies heat directly to the core Necessary for most patients with a core temp < 90° Fast!

10 Treatment: Core What About heated IVFs? Rewarming Heated Humidified Air Is heated IVF an effective Heat to 45°C/113°F rewarming method? 2-3°FriseinTF rise in T°/hr Indicated for ALL significantly hypothermic patients

Why is This? 70 Kg person is 60% water: = 42 L of fluid

If 42 L of fluid is at 85°F and you add 1 additional L of fluid at 110°F...How much NO! difference does it make? Only 0.3°C/0.6°F per Liter

11 Treatment: Treatment: Core Rewarming Therapeutic Peritoneal Lavage

Heated irrigation of body cavities Abdominal Irrigation (“TPL”) ~3°F/hr Thoracic Irrigation Very effective (up to 10°F/hr) Ant/post chest tubes

Treatment: Thoracic Irrigation Treatment: Rewarming • Video 2: Thoracic Irrigation Extracorporeal Blood Rewarming Fem-Fem Bypass CAVR-Ll1IfLevel 1 Infuser V V R Dialysis with a heat exchanger

12 Microwaves? Treatment: Physiologically normal at T < 93°F/34°C Don’t treat it—Self-limited

Treatment: Treatment: Ventricular Fib Occurs < 28°C/83.5°F Occurs Commonly at T < 86°F (30°C) Lidocaine is ineffective The rate is SLOW! Rewarm and defibrillate every few Resolves with treatment of Hypothermia degrees

13 Treatment: Asystole Other Treatments

Occurs physiologically at T < CPR 65°F/18°C Only when no detectable May occur spontaneously pulse Onlyyp responds to rewarmin g Pressor agents Caution with cardiac stimulation

HeatHeat--RelatedRelated Illness Statistics

 About 500 die each year in the U.S.  Hard to know exact number because it’s often under- reported  August 2003: at least 35,000 died in Europe

I’m Feelin Hot, Hot , Hot!

14 Chicago, August, 1995 Pathogenesis of Heat Illness

• Exogenous heat gain • Endogenous heat production

Photo: Daniel Schwen • Decreased dissipation

All tolled, 760 people, mostly the elderly and poor died that summer

Pathogenesis: Wet Bulb Globe Temperature! Exogenous Gain A Weighted Average… • Environmental temperature • Sun, workplace, home, sauna

• 10%: Dry, shaded • 70%: Wet thermometer • 20%: Unshaded black globe

15 Pathogenesis: Endogenous Pathogenesis: Endogenous Production Production

• What are some other causes... • Basal : 50-60 kcal/hr/m2 • Hyperthyroidism • 1°C/hr increase in T° if we had no • Neuroleptic Malignant mechihanism f fdiiti!or dissipation! Syndrome • Malignant • Cocaine, Amphetamines, 20x Increase in heat production is MDMA, LSD seenExercise?? during ! •

Pathogenesis: Decreased Dissipation: Decreased Dissipation

Yeah…But it’s a dry • Limits Sweating heatheat!! • Volume overrides heat dissipation • Impairs CV function • Insensible water loss • Dehydration is the • 1.5L/day (2% BW) most significant factor • Exercise: 1-2 L/hr affecting the ability to • Maximum gastric emptying dissipate heat! • 1-1.5 L/Hr

Hullraisere on Panoramio.com

16 QUESTION? Spectrum of Illness

How much of the Heat Heat Heat Prickly lost fluid does Edema Syncope Heat thirst alone replace? Heat Exhaustion

Only about 2/3 of the Heat needed fluids Stroke

Heat Exhaustion Heat Exhaustion  Flulike symptoms – , , weakness, nausea,  Cool shaded environment , vomiting  Oral rehydration if capable  Tachycardia, orthostatic but may need IVF due to hypotension large amount tfls of volume l ltost as sweat  Sweating is generally present  Cooling is not necessary but  Temperature is < 40°C (104°F) it can make the patient feel  Mental status and neurologic better exam are normal

17 What is the Most Important Thing to Tell a Discharged Heat Exhaustion Patient???

Heat Stress For 48 Hours

Heat Stroke Heat Stroke

• Catastrophic, life-threatening  Temperature > 40.5°C (105°F) emergency  MENTAL STATUS CHANGES: • Failure of thermoregulatory Hallmark is severe CNS dysfunction mechanisms  • Multisystem /organ  Delirium damage  • Damage is a function of T° max  Coma and duration of T° elevation

18 Multi-Organ Dysfunction Heat Stroke: Area of Confusion

 Encephalopathy   Acute renal failure • Can the temperature be  ARDS less than 105°F and still  Myocardial/hepatocell be heat stroke?? ular/pancreatic  Intestinal ischemia/infarction  Bleeding complications – DIC www.gearfuse.com

Heat Stroke: Area of Confusion Classic (Epidemic) Heat Stroke

• Excess heat gain, impaired loss • Anhydrosis (sweat cessation) • Occurs during heat waves • Elderly, very young, • Sweat gland poor, debilitated • DhdDehydrati on • +/- inciting • Sweating can persist to T° > • Sweating is less likely 42°C (108°F)

politicalhumor.com

19 Vikings football player dies of heat stroke Exertional Heat Stroke August 2, 2001 Posted: 6:26 AM EDT (1026 GMT)

Korey Stringer died early Wednesday of heat stroke • XS heat production, overwhelmed loss mechanisms EDEN PRAIRIE, Minnesota (CNN) -- Pro Bowl offensive lineman Korey Stringer of the Minnesota • Young, healthy, athletes, military, etc. Vikings died of heat stroke early Wednesday, the team said. • Worse systemic involvement The 6 -foot-4, 335-pound Stringer, 27 , died at • Rhabdo, ARF, coagulopathy, Immanuel St. Joseph's Hospital -- Mayo Health System in Mankato, where the team holds its • More likely to still be sweating preseason practices.

His death came as dangerously hot weather continued to pose a problem for the central United Image from CNN How long can it take a runner in 100% States. Temperatures were expected to reach as high humidity at 8585°°FF to develop heat stroke? as 100 degrees in Iowa and Illinois on Wednesday. Stringer began exhibiting signs of heat stroke, including weakness and rapid breathing, after a morning practice session Tuesday.

Heat Stroke Claims Local Football Player August 12, 2005 Treatment: Cooling

OKLAHOMA CITY -- Medical examiners said that an done on Douglass High School • Evaporative cooling (Khogali method) football player Chris Stewart Friday determined that the 17-year-old died from • 15°C (59°F) mist + Fan 45°C (113°F) heat stroke. Stewart collapsed at a Tuesday practice, in • 0.06°C (0.1°F)/min 95-degree heat. He was taken to the hospital with elevated blood and body temperature and with some swelling. A senior, Stewart was projected to be a starter on the Trojans offensive line, and his family members said they were unaware of any pre-existing medical conditions Stewart might have had. Stewart was also an honor student. Services are pending, but expected to be Wednesday at 11 a.m. Image from CNN

20 The Evaporative Method TX: Cooling: Ice/Cold Water Immersion

• 0.13-0.16°C decrease/min (0.23-0.28°F)

Aggressive Resuscitation Treatment  ABCs  IVF – treat volume depletion  Avoid shivering  for seizures/shivering  Dantrolene is ineffective  Monitor for complications and treat

21 Good Prognosis Poor Prognosis

 Coagulopathy with liver  Recovery of central nervous hepatocyte damage system function during cooling  AST > 1000 U/L  Expected in the majority of  Lactic acidosis in classic form patients who receive prompt  Rectal temperature > 108° F and aggressive treatment  Prolonged coma r Furry r Furry u !

Don’t Forget Yo Don’t Forget Friends Friends! photowebster

22 Types

All the pathologic changes • – Expansion of caused by altered environmental trapped pressure • Altitude-related event • sickness – • accident disease • Blast injury that produces an overpressure effect

Pressure Pressure Top of Atmosphere

1 in • At 33 ft of ATM

• -ATM 1 in 14.7 psi • 33 ft seawater Air 1 1- • 10 m seawater • 1 atm ATM

• 760 mmHg -ATM • 760 Torr Water 1 1-

23 Flying : Boyle’s Law

• Most commercial • “The volume 0 ft of a gas is 1 ata aircraft are inversely pressurized to 8000 ft proportional 33 ft • 0.73 ATA to the 2 ata pressure • FiO2 21% but exerted upon functionally less it” 66 ft molecules of 3 ata

per breath ~ 16% FiO2 Depth Pressure

Middle Squeeze- Barotitis media

• Most common diving- related barotrauma Consequences of • Failure to equalize Pressure • Too rapid descent or infection/inflammation

• TM is pushed inward and can rupture

24 Other Barotrauma Scuba Rule # 1

• Barosinusitis • • Alternobaric Never Hold • Face mask squeeze Your Breath!

BreathBreath--holdingholding Kills

Blowing Bubbles Exogenous Entry of Air 33 ft

Air Embolism

66 ft

25 Pulmonary Over- Air-Gas Embolism (AGE) Pressurization  Bubbles enter the pulmonary venous circulation from ruptured alveoli Can get: Pneumothorax,  Usually develops right after diver , SQ surfaces  Sudden LOC = Air embolus until emphysema, rupture into pulmonary proven otherwise vein causing  Cardiac Simple pneumothorax may progress • Ischemia—dysrhythmias, cardiac to tension on further ascent arrest • Neurologic • LOC, confusion, stroke-like sx

Cerebral Air-Gas Embolism—CAGE Hyperbaric Oxygen and Bubble Reduction • As pressure increases, the bubble size

decreases and O2 replaces the inert gas in the bubble (N2), which promotes

22ATA ATA 1 ATA

26 Air Embolism (DCS)

• Recompression in hyperbaric chamber  Henry’s Law: “The 0 ft O2 1 ata amount of gas (O O O • Transport supine 2 2 2 and N2) dissolved 33 f t O2 O2 O2 • 100% oxygen, intubate PRN iliid(bldin a liquid (blood 2 ata • IVF plasma) is O2 O2 O2 O2 • Aspirin for antiplatelet proportional to its O O O O O activity if not bleeding 2 2 2 2 2 ” O O O O O O 3 ata • Lidocaine 66 ft 2 2 2 2 2 2 Depth Pressure

DCS DCS

• The longer and deeper the dive, the more nitrogen gas will be accumulated in the body

27 DCS Type I DCS

• Periarticular joint pain is Slow ascent allows for compensation the most common symptom of DCS Elimination Ischemic Joint Pains • DlldDull, deep ach e th thtiat is mild then more intense • Palpable tenderness • “The Bends”

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Type I DCS Type II DCS = 10-15%

• Cutaneous • Pruritus • Nervous system • Cutis marmorata • Hyperemia • Pulmonary system (< 2%) • Orange peel • Lymphedema • Fatigue, especially if severe

28 Neurologic DCS Pulmonary DCS

 Spinal cord is most common site  Lower thoracic and lumbar regions • “The Chokes”  Low back pain • May begin immediately after dive but  “heaviness” in legs often takes up to 12 hours to develop  Paresthesias • Triad – shortness of breath, cough, and  Possible bladder or anal sphincter dysfunction substernal chest pain or chest tightness  Brain – variety of symptoms and difficult • , tachypnea, and tachycardia to distinguish from AGE  Scotomata, headache, confusion, dysphasia

DCS Treatment Delivery of

 Monoplace Chambers ABCs 100% oxygen • Single patient IVF Recompression therapy  (DAN): 919-684- 8111 75-85% have good results when recognition and treatment are prompt

29 Multiplace Chamber Multiplace Chambers

30