Hypothermia(Hyperthermia)

Dr. Stella YiuStaff Emergency Physician

LMCC objectives

List clinical findings of hypothermia

Investigate

Initiate resuscitation for severe hypothermia

1. Clinical findings of hypothermia

Normal temp: 36.5 – 37.5 C

Effects

By Patrick J. Lynch, medical illustrator (Patrick J. Lynch, medical illustrator) [CC-BY-2.5 (http://creativecommons.org/licenses/by/2.5)], via Wikimedia Commons

Image credit: US public domain

Mild (32-35C)

Mild (32-35C)

Mild (32-35C)

Moderate (28-32C)

Image credit: James Heilman, MD

Moderate (28-32C)

Severe (<28C)

Image credit: jer5150, Wikimedia commons, Jeffrey Bary, Flickr creative commons

What precipitates hypothermia?

Increased heat loss

Alcohol

Sepsis

Burn

EM Ottawa

Exposure

14Photo credit: Jonathan Snyder, U.S. Air Force, UNC - CFC – USFK, CC by

2.0, via Flickr creative commons

Impaired thermostat

Metabolic (Cirrhosis, uremia, DM, Hypothyroid)

CNS (stroke, trauma, MS, Parkinson)

Drugs (Barbituates, TCAs)

2. Investigations

CDMQ: 25 M found passed out on street. Core temp 30C. Name 4 investigations.

Investigations

CBC, Cr, Lytes, Coag profile (DIC)

TSH

EKG

Osborn J waves

3. Resuscitation

Mild (32-35C): Passive external rewarm

Mod (28-32C): Active external rewarm

EM Ottawa

Mod (28-32C): Active external rewarm

23By Patrick J. Lynch, medical illustrator (Patrick J. Lynch, medical illustrator) [CC-BY-2.5 (http://creativecommons.org/licenses/by/2.5)], via Wikimedia Commons

Warm humidified Oxygen

EM Ottawa

Severe (<28)

Warm every cavitybut

Gentle handling

24

CDMQ: How do we do active core rewarming in severe hypothermia? (6)

Airway

Intubate Warm humidified oxygen

Circulation

Warm intravenous fluids

Pleural space

By Patrick J. Lynch, medical illustrator (Patrick J. Lynch, medical illustrator) [CC-BY-2.5 (http://creativecommons.org/licenses/by/2.5)], via Wikimedia Commons

Bladder

By User:Lennert B [GFDL (http://www.gnu.org/copyleft/fdl.html), CC-BY-SA-3.0 (http://creativecommons.org/licenses/by-sa/3.0/) or CC-BY-2.5

(http://creativecommons.org/licenses/by/2.5)], via Wikimedia Commons

Dialysis

By National Kidney and Urologic Diseases Information Clearinghouse, National Institute of Diabetes and Digestive

and Kidney Diseases, National Institutes of Health, USA [Public domain], via Wikimedia Commons

Photo credit: becre8tv, CC by 2.0, via Flickr Creative commons

Bypass

By Van Meurs, K, Lally, KP, Peek, G, Zwischenberger, Extracorporeal Life Support Organization, Ann Arbor 2005. [CC-BY-2.5

(http://creativecommons.org/licenses/by/2.5)], via Wikimedia Commons

MCQ 3: Patient is lethargic and bradycardic. Most appropriate warming method?

A. Pleural lavageB. Bladder irrigationC. IntubationD. Dry blanket and a snackE. Blanket with forced warm air

MCQ 4: 12 M found in snow. After 2hrs CPR and warming, asytolic. Core temp 27.5C. What is the most appropriate step?A. Stop resuscitation B. DefibrillationC. Continue CPR and warmingD. Warm water immersionE. Stop warming

Not dead until warm (>30-32) and dead

Hyperthermia

LMCC objectives

List predisposing illnesses

List clinical findings

Select investigations

Manage patient by various cooling methods

CausesEnvironm

ent Decreased heat dissipation

Metabolic heat

1. Predisposing illness

Metabolic causes: Heat production

Metabolic heatThyroid, pheochromocytomaMalignant hyperthermiaNMSSepsis

Decreased heat loss: Drugs

Decreased heat dissipation

ObesityDrugs (anticholinergics, serotonin)

2. Clinical findings

Case: The rave girl

Heat stroke: Hot + confusedT> 40Orthostatic BP, HR

CNS: Confusion, ataxic, cerebral edema, seizureCVS: CHF, pulmonary edema, CV collapse

Lab findings: Liver, Renal

Liver: necrosis

Rhabdomyolysis

DIC

3. Cooling methods

Basic cooling:

Photo credit: Kenneth Lu, Flickr creative commons

Photo credit: yellowcloud, flickr creative commons

More aggressive cooling

GI/Peritoneal lavage

Cardiac bypass

Stop cooling when temp < 40

LMCC objectives

List predisposing illnesses

List clinical findings

Select investigations

Manage patient by various cooling methods