CR - Environmental Disorders Flashcards
What is the order of tissue resistance to the flow of electrical current?
Least resistance - nerves, blood vessels, muscles, mucous membranes, moist or wet skin
Intermediate resistance - dry skin
Greatest resistance - bone, tendon, fat
Which organ system is least sensitive to an acute radiation exposure?
Central nervous system
What is the clinical feature that distinguishes heat stroke from heat exhaustion?
Central nervous system dysfunction
(in heat exhaustion, mentation is not impaired)
Which ENT injury is most likely to be present in a survivor of a lightning strike?
Rupture of the tympanic membranes
At what temperature does the hypothermic patient lose the ability to generate heat by shivering?
Below 32C (90F)
A patient complains of severe muscle cramping involving the calves, thighs, and shoulders. Questioning reveals that the cramps began after a bout of intensive physical activity and profuse sweating, during which he had been replacing fluid losses with a hypotonic solution. His body temperature is normal. What is the most likely diagnosis?
Heat cramps.
Inadequate replacement of salt from loss through sweating leads to hyponatremia and muscle cramps
What is the modified “rule of nines” which may be used in children?
Head = 18%
Abdomen = 9%
Thorax = 9%
Back = 18%
Each arm = 9%
Each leg = 13%
Perineum = 2%
Core temperature less than ____ is associated with increased myocardial irritability and can cause nearly any tachydysrhythmia or bradydysrhythmia, including conduction delays
30C (86F)
What is the most important cause of morbidity and mortality in near drowning?
Hypoxia
In patients with this injury, close observation (sometimes in the hospital) and referral to a plastic or oral surgeon is indicated because there is possibility of labial artery hemorrhage as the eschar separates
Electrical burns of the lip / mouth (particularly to commissures)
Rapid rewarming is the key initial therapy for this environmental emergency?
Frostbite
A patient presents with an acute abdomen after being outdoors. You notice that there is only mild tenderness but there is impressive rigidity.
What is the suspected diagnosis?
Black widow spider bite
(Bite is typically not noticed to the lower extremity or genitalia)
A scuba diver develops acute confusion and ataxia immediately after an ascent to surface.
What is the diagnosis
Arterial gas embolism
A patient presents with extreme fatigue and profuse sweating while training on a very hot day. He complains of lightheadedness, nausea, vomiting, and a dull headache. He is tachypneic, tachycardic, and hypotensive. Body temperature is only mildly elevated. What is the most likely diagnosis?
Heat exhaustion.
Electrolyte and fluid losses from sweat lead to hypovolemia and decreased cardiac output; no significant abnormalities on neurologic testing, may have some ataxia and lightheadedness
The whole body dose of ionizing radiation determines the timing of onset of symptoms. The higher the level of exposure, the ___ symptoms develop
Earlier
The first signs are most commonly GI symptoms: nausea, vomiting, diarrhea and bloody stools. Symptoms start with doses >1Gy or 100 rad. LD50 when doses reach 4.5 Gy
What is the best predictor of survival in patients with radiation exposure?
The absolute lymphocyte count, 48 hours after exposure.
(Andrews lymphocyte nomogram)
What is the treatment of puncture wounds (stings) from sea urchins, stingrays, or lionfish?
- Remove the victim from the water immediately.
- Address possible allergic reaction
- Hot water immersion at highest temperature patient can tolerate for 30 minutes or until pain resolves
- Normal wound management
- Prophylactic antibiotics for deeper wounds, foreign bodies, or in immunocompromised patients
Concerning the initial management of patients with radioactive skin contamination, is it preferable only to wash or to wash and scrub the skin?
Washing with soap and water. May scrub skin gently until any signs of skin breakdown appear to avoid introduction of radioactive material into the underlying tissues
Does successful recovery from tetanus confer immunity to the disease?
No
The patient needs full primary immunization plus boosters through the years as otherwise indicated
Which tick-borne illness is characterized by severe retro-orbital headaches and photophobia and requires only supportive therapy?
Colorado tick fever
Clinical presentation: a patient presents ill with fever and a rash. The rash begins as discrete red maculopapular lesions on the writs and ankles. It then spreads to the trunk. Early on, the lesions were blanched but later become petechial.
What disease characteristically does this?
Rocky mountain spotted fever
Circular skin lesions with bright red to blue red border and a pal center are characteristic of ____ ____, which is the hallmark of early ____ ____
Erythema migrans
Lyme disease
Antibiotic therapy for adults (nonpregnant and nonlactating) and children for lyme disease stage 1 is ____
Doxycycline for 10-14 days.
Dosing 100 mg PO BID in adults and 2-4 mg/kg divided BID with max dose of 200 mg/day in pediatrics (treatment in pediatrics not to exceed 21 days)
Which animals are most likely to harbor the rabies virus?
Which animals are least likely vectors for rabies?
Most common: #1 globally is the domestic dog (only travel to foreign countries has caused fatal dog bite related rabies in the US since 2003), skunks, bats, raccoons, foxes
Least common: rodent, squirrels, chipmunks, rats and mice and rabbits have not been known to transmit rabies to humans.
Note: rabies can affect all mammals
