chapter 25 Submersion Incidents Flashcards
is an incident in which someone is submerged or immersed in a liquid that results I a primary respiratory impairment
drowning
refers to medical conditions resulting from changes in ambient pressure. Various activities are associated with pressure changes. Scuba diving is the most frequently cited example, but pressure changes also affect people who work in other pressurized environments (for example, caisson workers), and people who move between different altitudes.
dysbarism
is bloating of the stomach when air is pumped into it.
gastric distention
The mammalian diving reflex is a reflex in mammals which optimizes respiration to allow staying underwater for extended periods of time.
mammalian diving reflex
is a lipoprotein that lines the inner surface of the alveoli. it maintains a surface tension that keeps the alveoli from completely collapsing
surfactant
The most significant determining factor for patient survival in a drowning are
duration and the severity of hypoxia a patient suffers
Why is ALS non effective in patients with body core temp less than 86 degrees
you can only use the AED once on a patient with body core temp less than 85 degrees, their BCT must be above 86 for shockrythem to be effective.
how does mammalian diving reflex work
- Heart rate slows (Bradycardia)
- Blood flow to extremities constricted (peripheral vasoconstriction)
- Blood and water allowed to pass through organs and circulatory walls to chest cavity (blood shift)
what do you do if a drowning patient is suspected of being hypothermic
access pulse for 10 seconds
if pulseless begin chest compressions
apply AED
- water enters lungs and at same time gasping occurs. Laryngeal spasm may follow
- airway resistance increased, reflex pulmonary vasoconstriction occurs, surfactant is diminished and lung compliance is decreased
- water shifts from alveoli into circulation
- swallowing, vomiting and aspiration of vomit is likely
- phase of secondary apnoea occurs followed by further involuntary gasping and loss of consciousness
- respiratory arrest and cardiac arrhythmias occur several minutes later
This is known as
the pathology of drowning
10-20% of drowned patients
- little or no fluid found in lungs
- death probably due to profound laryngospasm. This is followed immediately by outpouring of thick mucus, which with bronchospasm, may prevent entry of water when spasm relaxes shortly before death by asphyxiation occurs
- more common in adults
- lung reflexes facilitated by raised blood alcohol levels
This is known as
Dry drowning
drowning have a tendency to washout________causing atelectasis
surfactant
an acute injury to the lungs that results in alveolar flooding, atelectasis and a severe oxygenation defect, but is not due to heart failure. In its early stages, it can cause shortness of breath (dyspnea), increased rate of breathing (tachypnea), and low oxygen saturation (hypoxemia).[
Acute respiratory distress syndrome (ARDS),
emergenct for drowning patient
(patient with respiratory distress)
positive pressure ventilation with highest supplement oxygen
(patient breathing sponatuosly no distress)
use CPAP
or nonrebreather mask 15 lpm
what are the four laws of physics that play a major role in adverse conditions and emergencies by divers
Boyle law
Daltons law
Henry law
Charles LAW
“the pressure exerted by a mixture of gases is equal to the sum of the pressures that would be exerted by the gases individually”.
Daltons law
How does Dolton’s law affect scuba divers
This is relevant to scuba diving with regard to the individual gases in a mix that will compress equally as outside pressure increases.
Read more: http://www.ehow.com/about_6692411do-laws-relate-scuba-diving.html#ixzz2ildkIhAw
“At a constant temperature, the amount of a given gas that dissolves in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid.” This is known as
Henry’s law
How does Henry’s law affect scuba divers
This essentially says that as pressure increases then our bodies will absorb more gas. Thus at greater depths the amount of gas absorbed into our body will be greater. This means that deeper dives have to be calculated shorter to allow for this, or risk the possibility of decompression sickness.
As pressure increases, volume decreases. As pressure decreases, volume increases.
Boyles law
How does Boyles law effect scuba divers
This is relevant to scuba diving in the context of depth and water pressure. Pressure increases with depth, and thus volume will be decreased as a descent is made and will increase upon ascent. This means that every air space on the diver, both dead air space (such as the mask) and live air spaces (such as the lungs), must be paid attention to avoid problems such as decompression sickness and lung over-expansion injuries. Therefore breathing techniques, equalizing air spaces and never holding your breath are affected by Boyle’s law. In addition buoyancy can be affected too, with wetsuit material being compressed and thus becoming less buoyant.
cooling a gas decreases the volume of the gas. If the volume does not change then pressure must decrease.
Charles law
How does Charles law effect scuba divers
This means that if a scuba tank is heated then the pressure will increase, which accounts for accidents that have happened with scuba tanks being left in hot environments.
also known as divers’ disease, the bends or caisson disease describes a condition arising from dissolved gases coming out of solution into bubbles inside the body on depressurisation.
Decompression sickness (DCS)
what are the effects of the bubbles on the body
- act as emboli and cause obstruction in the circulation
2. they compress or stretch the blood vessels and nerves
What are the types on Decompression sickness
Type I (‘simple’)” for symptoms involving only the skin, musculoskeletal system, or lymphatic system,”
Type II (‘serious’)” for symptoms where other organs (such as the central nervous system) are involved.
Type II DCS is considered more serious and usually has worse outcomes.
what are the predisposing factors of DCS
Ascent from depth
Leaving a high-pressure environment
