Enviro Emergencies Flashcards
1
Q
distribution of elect. injuries?
A
- young kids: oral contact w/ electric cords and outlets
- adults: construction and electrical workers (90% men)
2
Q
Mech of elect. injury?
A
- direct effect of electrical current on body tissues: severity depends on voltage, duration, type, current path throughout body, enviro factors
- conversion of elect energy to thermal energy results in deep and superficial burns
- exit wound often larger than entrance site
- as current flows through body, greatest damage is sustained by nerves, blood vessels and muscle
3
Q
Low voltage AV current injury vs high voltage AC and DC injury?
A
- low voltage AC: will cause muscle tetany, causing injured person to cont grasp source, increasing contact time, tend to cause V fib
- high voltage: cause single violent muscular contraction which tends to throw victim from source, increasing risk of blunt trauma, and blast injuries, tend to cause asystole and resp arrest
4
Q
initial PE of electrical injury?
A
- primary, secondary surveys, ABCs, C spine immobilization
- IV 2 large bores, fluid repalcement: isotonic crystalloid
5
Q
Neuro PE of electrical injury?
A
- CNS: neuro impairment occurs in 50% of high voltage injuries, transient LOC, agitation, confusion, coma
- visual disturbances: pupils may be fixed and dilated or asymmetric due to autonomic dysfxn, 50-80% of those struck by lightening have ruptured eardrums
- spinal cord injuries:
fxs, current itself (ascending paralysis, spinal cord syndromes, can be immediate, transient or delayed) - peripheral nerves: injuries often involve hand touching power source
6
Q
PE for cutaneous wounds for electrical injury?
A
- burns: entry and exit pts
- look for entrance and exit wounds and degree of burns
- burns can be cleansed and dressed w/ silver suflfadizine
- extremities need careful exam for neurovasc compromise, compartment syndrome
- oral burns:
kids who chew on wires, vasc injury to labial artery can occur, responsible parents can do home monitoring
7
Q
Bone PE in electrical injury?
A
- bone has highest resistance of any body tissue, generates greatest amt of heat when exposed to electrical current
- areas of greatest destruction are often deep tissue surrounding long bones
- deep electro-thermal tissue injury can result in edme and the development of compartment syndrome
8
Q
Renal PE of electrical injury?
A
- rhabdo can occur and be complicated by pigment induced renal failure
- hypovolemia due to extravascular extravasation of fluid can lead to prerenal azotemia and acute tubular necrosis
9
Q
Tx of electrical injury? labs?
A
- trauma: ABCs, c spine
- dysrythmias
- aggressive fluid replacement: isotonic crystalloid fluids, acute hypotension should prompt search for thoracic or intra-abd bleeding secondray to blunt trauma
- labs - lytes, BUN/Cr, CK, serum and urine myoglobin, CBC, EKG
- watch lytes
- wound care
- myoglobinurea: can cause renal failure, amputation may be necessary
- tetanus prophylaxis
- tx seizures
- consult to general surgeon
- kids w/ oral injuries: ENT
- preg women: OB
10
Q
Monitoring electrical burns?
A
- continuous CV monitoring: arrhythmias occur 15% of time after injury
- needs to be monitored for development of compartment syndrome
- I and O followed, maintain output more than 100 mL/hr as goal, monitor for rhabdo, and renal failure
11
Q
PP of lightning strikes?
A
- DC current
- can result in:
direct strike
side flash
ground current
step potential (cow is worse off than you) - extensive tissue damage and renal failure are rare
- immed cardiac arrest result from direct current depolarization of myocardium and can result in systole
- resp arrest from depolarization and paralysis of medullary resp center
12
Q
Minor injuries resulting from lightning strikes?
A
- stunned pt
- confusion, amnesia
- short term memory problems
- HA
- muscle pain
- parasthesias
- temporary visual or auditory problems
- most minor injuries have gradual improvement, no long term sequelae
13
Q
What would alert you that the pt sustained a lightning injury?
A
- pt found unconscious or in arrest outside during weather conditions
- pupil dilation or aniscoria may occur
- ruptured tympanic memrbanes or fern like erythematous skin marking
14
Q
Tx of lightning strike injury?
A
- aggressive resuscitation
- ACLS, CPR
- cardiac monitoring, SAO2, BP
- 2 large bore IVs
- high flow O2
- secondary survey for occult injuries:
cutaneous burns
ocular involvement
auditory involvement
MSK fxs - labs
- tetanus
- moderate to severe injuries: admite to critical care unit
- minor: admit, closely monitor cardiac and neuro status
15
Q
How common is drowning in US?
A
- 3rd MC cause of accidental death in US
- 2nd MC in those younger than 45
- leading cause of death in kids under 5 in states where pools and beaches are more accessible
16
Q
RFs for near drowning?
A
- inability to swim or overestimation of swimming capabilities
- risk taking behavior
- use of EToH or drugs
- inadequate adult supervision
- hypothermia which can lead to rapid exhaustion or cardiac arrhythmias
- concomitant trauma, CVA or MI
- hyperventilation prior to shallow dive
17
Q
PP of drowning?
A
- after submersion degree of pulm and in particular CNS insult determine ultimate outcome
- drowning begins w/ period of panic:
loss of normal breathing pattern, breath holding, air hunger and struggle to stay above water - reflex inspiratory efforts occur:
leading to hypoxemia by:
aspiration, reflex laryngospasm
18
Q
Diff b/t dry drowning and wet drowning?
A
- dry: 10-20% of submersion injuries, caused by laryngospasm, followed by hypoxia and LOC
- wet: aspiration of water, dilution and washout of pulmonary surfactant
- diminished gas transfer
- atelectasis
- ventilation-perfusion mismatch
19
Q
Diff b/t fresh water and salt water drowning?
A
- fresh:
transient hemodilution, causing blood cells to swell and burst. If large enough vol are aspirated, sig hemolysis is possible - salt water:
lungs fill w/ salt water which draws blood out of bloodstream and into lungs, build up of Na+ in alveoli stops O2 from reaching blood
20
Q
End organ effects of drowning?
A
- pulm: fluid aspiration, both salf and fresh water: wash out surfactant, producing noncardiogenic edema and ARDS -S/S: SOB, rales, wheezing
- neuro: hypoxemia, ischemia cause neuronal damage, can produce cerebral edema and elevated ICP, 20% near drowning victims sustain neuro damage limiting fxnl recovery
- CV: arrhythmias 2nd to hypothermia and hypoxemia, sinus brady and fib more common
- acid-base and lytes: metabolic and/or resp acidosis often occurs, sig lyte imbalances don’t generally occur except those submerged in unusual media: dead sea
21
Q
Prehosp care of drowning victim?
A
- asses need for CPR (Pulses may be weak)
- support neck in neutral position
- heimlich manuever or other postural drainage techniques dont help - DON’T delay rescue breathing
- hypothermic pts should be rewarmed
22
Q
Management of drowning victim in ER?
A
- continue resuscitative efforts
- head and spinal cord injuries should be sought (precip pre near drowning)
- re-warming: blankets, bair hugger, overhead warmers, continue resuscitation unitl pt is at 32-35 C (90-95 F)
- pts w/ GCS 13 or greater: O2, observation for 4-6 hrs, if pulm exam and room air O2 remain normal - d/c, if not better reassess and admit
- GCS less than 13: O2, CXR, labs: ABGs, CBC, CMP, could develop dilutional hyponatremia and have seizures
- PT/PTT UA, CK urine myoglobin, urine drug screen
