Chapter 38 Environmental Emergencies Flashcards
1. Thermoregulation is a function of the: A) diencephalon. B) anterior hypothalamus. C) peripheral vasculature. D) posterior pituitary gland.
Ans: B
Page: 1806
Type: General Knowledge
- Which of the following statements regarding thermoregulation is correct?
A) Thermogenesis is how the human body eliminates excess heat in order to maintain homeostasis.
B) At a constant temperature of 97.6°F, the metabolic reactions of the body proceed at their optimal level.
C) Temperature of the brain and thoracoabdominal organs varies widely, depending on the body’s needs.
D) Skin temperature can fluctuate a great deal, which is why it plays a major role in thermoregulation.
Ans: D
Page: 1806
Type: General Knowledge
- In situations where the environment is a factor, the MOST accurate means of determining a person’s core temperature is to:
A) use a rectal thermometer that is capable of measuring extremes of temperature.
B) use a tympanic thermometer and then add two degrees to the reading that you obtain.
C) obtain a tactile temperature by placing the back of your hand on the patient’s forehead.
D) place a mercury thermometer in the patient’s axilla and wait 2 to 3 minutes before reading it.
Ans: A
Page: 1807
Type: General Knowledge
- The thermolytic tissues in the hypothalamus are mediated by the:
A) endocrine system.
B) sympathetic nervous system.
C) parasympathetic nervous system.
D) signals of the adrenergic nervous system.
Ans: C
Page: 1807
Type: General Knowledge
- The basal metabolic rate is MOST accurately defined as:
A) the expenditure of heat energy during strenuous exertion or exercise.
B) the heat energy produced at rest from normal body metabolic reactions.
C) the balance between heat production and heat elimination from the body.
D) a constant fluctuation in core body temperature to maintain homeostasis.
Ans: B
Page: 1807
Type: General Knowledge
6. Of the many factors that affect the basil metabolic rate, the MOST important factor is: A) the person's age. B) the person's sex. C) the person's level of activity. D) the person's body surface area.
Ans: D
Page: 1807.
Type: General Knowledge
- An increase in core temperature causes the:
A) anterior pituitary gland to send signals via afferent pathways in the sympathetic nervous system to increase the heart rate.
B) hypothalamus to send signals via efferent pathways in the autonomic nervous system, causing vasodilation and sweating.
C) anterior pituitary gland to send signals via efferent pathways in the sympathetic nervous system, causing widespread vasoconstriction.
D) hypothalamus to send signals via afferent pathways in the parasympathetic nervous system, resulting in vasoconstriction and sweat production.
Ans: B
Page: 1807
Type: General Knowledge
8. The transfer of heat from a hotter object to a cooler object by direct physical contact is called: A) radiation. B) convection. C) conduction. D) evaporation.
Ans: C
Page: 1808
Type: General Knowledge
9. A person blowing on hot food in an attempt to cool it is an example of: A) radiation. B) convection. C) conduction. D) passive cooling.
Ans: B
Page: 1808
Type: General Knowledge
10. Which of the following factors decreases the body's ability to eliminate excess heat through evaporation? A) High humidity B) Wet clothing C) Low wind chill D) Hyperventilation
Ans: A
Page: 1808
Type: General Knowledge
11. When the outside temperature approaches or exceeds skin surface temperature, heat loss by \_\_\_\_\_\_\_\_\_ and \_\_\_\_\_\_\_\_\_ diminishes and eventually ceases. A) convection, conduction B) conduction, evaporation C) evaporation, radiation D) radiation, convection
Ans: D
Page: 1808
Type: General Knowledge
- For evaporation of sweat to be an effective cooling mechanism:
A) the relative humidity must be greater than 90%.
B) the environmental temperature must be at least 95°F.
C) ambient air must be relatively unsaturated with water.
D) ambient air must be saturated with a great deal of water.
Ans: C
Page: 1808
Type: General Knowledge
13. In a cold environment, the body produces and conserves heat through all of the following mechanisms, EXCEPT: A) shivering. B) vasoconstriction. C) hyperventilation. D) thermogenesis.
Ans: C
Page: 1808
Type: General Knowledge
14. An increase in core body temperature due to inadequate thermolysis is called: A) heatstroke. B) heat illness. C) heat cramps. D) heat exhaustion.
Ans: B
Page: 1808
Type: General Knowledge
- Older people are at increased risk for heat-related illnesses because:
A) they are more likely to have chronic medical conditions that interfere with normal heat regulation.
B) they have proportionately higher metabolic heat production when compared to younger adults.
C) they are often taking beta adrenergic agonists, which can lessen a tachycardic response to heat.
D) they acclimatize more rapidly than younger adults, which results in faster heat production.
Ans: A
Page: 1809
Type: General Knowledge
16. Which of the following medications would be the LEAST likely to increase a person's risk for a heat-related illness? A) Diuretics B) Beta blockers C) Antihistamines D) Alpha antagonists
Ans: D
Page: 1808
Type: General Knowledge
17. A person taking levothyroxine (Synthroid) is at an increased risk for a heat-related illness secondary to: A) tachycardia. B) hypothalamic suppression. C) an increased metabolic rate. D) lowering of the blood pressure.
Ans: C
Page: 1808-1809
Type: General Knowledge
18. Factors that increase internal heat production include all of the following, EXCEPT: A) response to infection. B) excess caffeine. C) hypothyroidism. D) Parkinson disease.
Ans: C
Page: 1809
Type: General Knowledge
19. Impaired vasodilation: A) increases heat absorption. B) interferes with heat dissipation. C) decreases internal heat production. D) is caused by beta blocker medications.
Ans: B
Page: 1809
Type: General Knowledge
20. All of the following factors contribute to heat cramps, EXCEPT: A) Gender B) Dehydration C) Salt depletion D) Muscle fatigue
Ans: A
Page: 1809
Type: General Knowledge
21. Heat cramps are caused by: A) sodium loss due to sweating. B) failure of the hypothalamus. C) increased potassium levels. D) increased urinary frequency.
Ans: A
Page: 1809
Type: General Knowledge
22. The FIRST step in treating a patient with a heat emergency is to: A) ensure that the airway is patent. B) assess the core body temperature. C) employ active cooling measures. D) move the patient to a cooler area.
Ans: D
Page: 1810
Type: General Knowledge
- The MOST likely cause of heat syncope is:
A) paroxysmal tachycardia.
B) vasodilation and dehydration.
C) underlying cardiovascular disease.
D) profound peripheral vasoconstriction.
Ans: B
Page: 1810
Type: General Knowledge
- In contrast to salt-depleted heat exhaustion, water-depleted heat exhaustion:
A) is much less likely to occur in a patient who takes diuretic medications for hypertension.
B) occurs primarily in geriatric patients and is due to factors such as decreased thirst sensitivity and immobility.
C) usually takes several hours or days to develop and occurs when regular water is used to replenish sodium and water.
D) is the result of prolonged exertion in a hot environment coupled with the excessive intake of hypotonic fluids.
Ans: B
Page: 1810
Type: General Knowledge
25. Which of the following clinical findings would you NOT expect to encounter in a patient with heat exhaustion? A) Abdominal cramping B) Mental disorientation C) Hypertension upon standing D) Body temperature of 103°F
Ans: C
Page: 1811
Type: General Knowledge
26. The diagnosis of heatstroke is usually made when a patient has a high core body temperature and: A) an altered mental status. B) an absence of sweating. C) a history of heat exposure. D) a heart rate above 140 beats/min.
Ans: A
Page: 1811
Type: General Knowledge
- Classic heatstroke:
A) is also called active heatstroke and is usually seen in diabetics.
B) presents with a high core body temperature and profuse sweating.
C) affects young people and is often accompanied by hypoglycemia.
D) typically affects older people and is not associated with exertion.
Ans: D
Page: 1812
Type: General Knowledge
28. In contrast to classic heatstroke, exertional heatstroke: A) causes hyperglycemia. B) presents with hot, dry skin. C) affects young, healthy people. D) is associated with diuretic use.
Ans: C
Page: 1812
Type: General Knowledge
- Patients with heatstroke:
A) present initially with hot, dry skin.
B) are typically bradypneic and hypotensive.
C) have a core temperature greater than 104°F.
D) should routinely be given 50% dextrose.
Ans: C
Page: 1813
Type: General Knowledge
30. Which of the following clinical findings suggests a cause of a patient's hyperthermia other than heatstroke? A) Dehydration B) Intermittent chills C) Moist, pale, hot skin D) Pupillary constriction
Ans: B
Page: 1813
Type: General Knowledge
- The MOST important treatment for a patient experiencing heatstroke involves:
A) antipyretic administration and high-flow oxygen.
B) rehydration with IV fluids and ice water submersion.
C) rapid transport and cooling to the point of shivering.
D) removal from the hot environment and rapid cooling.
Ans: D
Page: 1813-1814
Type: General Knowledge
- Which of the following statements regarding frostbite is correct?
A) Frostbite is an ischemic injury that is classified as superficial or deep.
B) Frostbite most commonly affects the trunk and lower extremities.
C) Frostbite can only occur if the ambient temperature is below 40°F.
D) Increased blood flow to an extremity exacerbates deep frostbite.
Ans: A
Page: 1814
Type: General Knowledge
33. Cigarette smoking predisposes a person to frostbite because it: A) causes arteriolar constriction. B) decreases the blood pressure. C) causes peripheral vasodilation. D) increases peripheral blood flow.
Ans: A
Page: 1815
Type: General Knowledge
34. The MOST common symptom of superficial frostbite is: A) localized edema. B) white, waxy skin. C) an altered sensation. D) cyanosis of the skin.
Ans: C
Page: 1815
Type: General Knowledge
35. Treatment for a superficial frostbite injury includes: A) rewarming with radiant heat. B) elevating the frostbitten part. C) rewarming the area with hot water. D) gently rubbing the frostbitten area.
Ans: B
Page: 1815-1816
Type: General Knowledge
36. A deeply frostbitten extremity: A) is typically bright red and painful. B) usually heals well with rewarming. C) requires amputation due to gangrene. D) is cold, hard, and without sensation.
Ans: D
Page: 1815
Type: General Knowledge
- When frozen tissues thaw slowly:
A) the risk of gangrene and subsequent amputation is much lower.
B) the resultant ice crystals are smaller in size and cause less damage.
C) the injured area becomes flushed or pale, but is relatively painless.
D) partial refreezing of melted water may cause greater tissue damage.
Ans: D
Page: 1815
Type: General Knowledge
- In addition to your transport time to the hospital, prehospital treatment of a frostbitten body part is MAINLY dependent upon:
A) the percentage of the body surface affected and the patient’s general underlying health.
B) whether the affected part has been partially or completely thawed prior to your arrival.
C) the patient’s core body temperature and blood pressure at the time of initial patient contact.
D) the estimated length of exposure to the cold environment and the potential for concomitant injuries.
Ans: B
Page: 1815
Type: General Knowledge
39. Hypothermia is defined as a decrease in core body temperature, generally starting at: A) 96°F. B) 95°F. C) 94°F. D) 93°F.
Ans: B
Page: 1816
Type: General Knowledge
40. A patient may become hypothermic for all of the following reasons, EXCEPT: A) decreased thermolysis. B) inadequate thermogenesis. C) impaired vasoconstriction. D) excess environmental cold stress.
Ans: A
Page: 1816-1817
Type: General Knowledge