9.1 Environmental Heat Stroke (Cameron Et Al.)

Front 1

What does "Aggressive Rapid Cooling" equate to ?

Back 1

Aggressive Rapid cooling at a rate of :

0.1 degree / minute

Front 2

Which of the following is the more superior method of cooling technique :
A. Ice to vascular beds
B. Evaporative cooling via convection : Fanning + mist spray

Back 2

B.

Front 3

List the methods involved in rapid aggressive cooling in Heat Stroke.

Back 3

1. Cold IV fluids
2. Evaporative cooling -convection
- Fanning and mist spray
3. Ice to vascular beds

Front 4

Which is incorrect regarding Heat Stroke ?
A. It is a time critical Medical Emergency
B. Neurological dysfunction includes Seizures and coma.
C. There are 3 classifications ,including Exertional and Classical.
D. The Temperature is > 40 degrees.

Back 4

C. 2 classifications:

1. Exertional - exposure in a thermally stressful environment.
2. Classical - Impaired thermostat from
a. drugs
b. Illness

Front 5

What are the 2 main differences between Heat exhaustion and Heat stroke ?

Back 5

1. Temperature ( < 40 for Heat Exhaustion and > 40 degrees for Heat Stroke )
2. Neurological Dysfunction : Heat exhaustion has normal cognitive state -Heat Stroke has confusion / seizures /coma

Front 6

What pharmacological treatments are used in Heat Stroke ?

Back 6

1. Benzodiazepines - Seizures
2. Phenothiazines ( Chlorpromazine ) - Shivering
3. Frusemide - for diuresis once adequately crystalloid filled

Front 7

What pharmacological methods in heat Stroke are ineffective, and should be avoided ?

Back 7

1. Aspirin
2. paracetamol

Front 8

What Investigations are ordered in Heat Stroke

Back 8

1. FBC - WCC
2. U+E - renal function / hypo-hyperkalaemia
3. LFT - Liver dysfunction
4. Coags - Coagulopathy / DIC
5. CK - rhabdomyolysis
6. Venous gas : metabolic / acid-base disturbance
- hyper / hypoglycaemia
- lactic acidosis
7. urine - myoglobin

8. Seek alternative causes for Heat Stroke
a. Sepsis : Lactate and blood cultures
b. AMI : troponin
c. Toxicology levels - paracetamol / ethanol ingestion
d. BHcG - pregnancy
e. CT Brain - generalised / focal Neurology

Front 9

List the major Heat related illnesses.

Back 9

1. Heat exhaustion and Exercise-Associated Collapse (EAC) ** [ * most common ED presentation ]
2. Heatstroke
3. Serotonin toxicity
4. Neuroleptic Malignant Syndrome
5. Malignant Hyperthermia

Front 10

What are the organ level Pathophysiological processes that occur with Core Body Temperature > 40-42
degrees ?

Back 10

1. Neurological - CNS
2. Cardiovascular - Pulmonary oedema
3. Renal Failure
4. Liver Failure
5. Electrolyte disturbance
6. Disseminated Intravascular Coagulation (DIC)
7. Rhabdomyolysis

Front 11

Which of the following is incorrect regarding Heat-Related Illnesses ?
A. Heatstroke is the failure of the hypothalamic Thermostat.
B. Delerium Tremens and Dystonias can lead to Heatstroke.
C. Malignant Hyperthermia and Neuroleptic malignant Syndrome and Serotonin Syndrome are all CNS -mediated processes.
D. Aspirin can be associated with Heatstroke.

Back 11

C.
Malignant Hyperthermia is purely peripheral in origin - with the release of calcium from the Sarcoplasmic Reticulum of Muscles and resultant muscle contractions +++.
NMS and SS are Centrally mediated Syndromes.

Front 12

What is the Classic Triad of Heatstroke ?

Back 12

1. Core Temperature above 41 degrees
2. Neurological dysfunction.
3. Dry, hot skin. ( sweat is present in > 50% patients with heatstroke, however ).

Front 13

Which of the following is correct regarding Heatstroke?
A. The degree of organ damage correlates with the degree and duration of the core body temperature above 38 degrees.
B. Cooling techniques should stop once the core temperature reaches 37 degrees.
C. The temperature of the water and fan-forced air in evaporative cooling should be tepid / warm.
D. Sedation and muscle relaxants / paralysis should be avoided in cooling heatstroke patients .

Back 13

C.

A. = 40 degrees
B. = 38-39 degrees
D. = Judicious use of sedation (BZD) +/- muscle relaxants / paralysis is important to control:
1. Agitation
2. Suppress shivering
3. reduced energy expenditures
4. Make patient receptive to (sometimes unpleasant) cooling techniques

Front 14

True or False :
The efficacy of salicylates and paracetamol depends on a normally functioning hypothalamus - in heatstroke the hypothalamic thermostat has failed -hence avoidance of aspirin and paracetamol.

Back 14

True