Physiology Flashcards
What is the normal core temp?
37 degrees celsius
Name the two systems of the circulatory system
Systemic and Pulmonary
hypertension
high blood pressure; obesity, stress, & age are risk factors; causes long-term effects
hypotension
low blood pressure; typical signs are fainting and dizziness
Diving reflex
bradycardia (heart rate reduces by 20%); peripheral vasoconstriction (decrease in blood flow to the extremities); blood shift (the shifting of blood plasma to the thoracic cavity)
Shallow water blackout
a diver hyperventilates themselves removing CO2 from their lungs consequently removing the natural trigger to breath from their bodies. Even though the body needs oxygen the body lacks the response to begin breathing.
Oxygen Poisoning
caused by breathing oxygen at elevated partial pressure (1.6bar pp; 6m; 70 with air)
Symptoms dizziness, nausea, visual disturbance, facial twitching, concentration disorder acoustic hallucination, convulsions & death
Treatment - patient needs fresh air
Hypoxia
oxygen deficiency caused by equipment problems, blockage of the respiratory passage, pneumothroax, hyperventilation
Symptoms - lack of muscle control, drowsiness, weakness, agitation, loss of consciousness
Treatment - 100% O2, symptoms similar to AGE treat for AGE is unsure
Nitrogen narcosis
caused by increased partial pressure of nitrogen (usually above PPN2 3.5bar)
Symptoms - laughter, mild euphoria; dizziness; response dizziness
Treatment - ascend, if mentally acuity doesn’t return abort dive
Hypercapnia
high level of carbon dioxide
Symptoms - breathing rapid & shallow; unconsciousness; similar to hypoxia (rule out before treating for hypercapnia)
Treatment - flush helmet or mask, exchange faulty equipment, fresh air - recovery should occur within 15 minutes
Carbon Monoxide poisoning
carbon monoxide displaces expygen from haemoglobin and interferes with cellular metabolism
cause by exhaust fumes entering compressor or breakdown of lubricating oil in compressor
Symptoms - similar to hypoxia; nausea, cherry red coloring (skin), unconsciousness, breathing stops
Treatment - resuscitation, 100% O2
Bartotrauma
pressure injury caused by differential pressures between body air cavities and external environment
Aural Barotrauma
Outer ear squeeze - caused by hood or wax buildup
Middle ear squeeze - damage between eardrum & eustachian tube
Parts of the ear
outer (Pinna, External auditory canal); Middle ear (ear drum, ossicles, eustachian tube); inner ear (oval window, cochlea, semi-circular canals)
Middle ear barotrauma of ascent
aka reverse block
blockage in eustachian tube
Dental Barotrauma
tooth cavity squeeze (tooth implosion on descent and blown out fillings on ascent)
Pulmonary Barotrauma
thoracic squeeze
Lung edmema
thoracic squeeze
injury to lung due to air spaces not equalizing to ambient pressure
symptoms - chest pain, bleeding, coughing of foamy blood, problems breathing
Lung edmema
accumulation of fluid in the lungs
Symptoms - chest pain, bleeding, coughing of foamy blood, breathing problems, paleness
Treatment - place patient in sitting position, administer O2
Decompression pulmonary barotrauma
syndrome which results in gas leaving its natural confines and entering wither the interstitial space within the lung, the pleural cavity or the blood stream
Main cause rupture of pulmonary tissue through an over expansion of the lungs during ascent
Lead to - AGE; Mediastinal Emphysema; Subcutaneous Emphysema; Pneumothorax, Tension Pneumothorax
Arterial Gas Embolism (AGE)
Gas from a ruptured lung enters the pulmonary circulation and migrates to the let side of the heart. Gas bubbles are then pumped into arteries and blockage occurs.
Symptoms - unconsciousness; numbness, weakness, paralysis
Treatment - decompression chamber, 100% O2
Mediastinal Emphysema
gas from ruptured lung escapes into the interstitial tissue space and from there into the mediastinum (space btwn lungs which contains heart), vessels and arteries
Symptoms - chest pain, change of voice, difficulties breathing
Treatment - 100% O2
Subcutaneous Emphysema
can develop from mediastinal emphysema; air collects in the subcutaneous tissues of the neck and head
Symptoms - skin swelling and crepitation
Treatment - 100% O2
Pneumothorax
alveolar gas escapes into the pleural space
a one time leakage
Symptoms - sharp chest pain, shortness of breath, blueing of lips and finger nail beds (cyanosis)
Tension pneumothorax
a continuous leakage of gas into the pleural space with every breath
can lead to a collapsed lung
heart and other lung are pushed to other side of thoracic cavity
Symptoms - in addition to those of pneumothorax, reduced movement of chest wall, tracheal shift
Sinus squeeze and sinus barotrauma of ascent
inability to equalize in pressure
caused by blockage
Symptoms - pain above eyes, cheeks and side of head, nasal bleeding
Other Barotraumas
Nips - skin trapped in folds of drysuit
Facial squeeze - mask pressure doesn’t equalize
stomach/bowel barotrauma - discomfort due to trapped gas
Decompression Illness (DCI)
The rate of decompression is too high, the bubble burden will exceed the lung capacity to clear bubbles. In this case bubbles will transit the lungs and enter arterial circulation.
Symptoms - 50% of divers develop symptoms mins after dive; after 3hr 90% of divers show symptoms/ limb pains occur 6hr w/in 90%
DCI risk factors
obesity, menstruation, hard physical labor during or after dive, cold water, flying after diving, too fast ascents, yo-yo diving
DCI symptoms
Cutaneous manifestation (skin bends) - formation of small bubbles in germinating layer of skin - itching and rash in affected area
Lymphatic manifestation - bubbles in lymphatic capillaries - enlarged lymph nodes, orange skin
Limb pains - probably formation of small bubbles in nerve ends
Neurological - cause unclear; symptoms dependent on part of brain affected
Audio-vestibular manifestation - formation of gas bubbles in balance organ - upset in balance and hearing, vertigo & nausea, flicking of eyes
Pulmonary manifestation (chokes)
DCI treatment table
all DCS gas embolism patients should initially be recompressed to 18m and start breathing oxygen
Treatment table 6
Hypothermia
temp falls below 35 degrees celsius
body loses heat through: evaporation, radiation, conduction, convection
Below 33 degrees condition becomes serious
Naked person could only survive 5-30min in 5degree water
Hyperthermia
body rises above 39 degrees celsius
caused by high outside temp
Drowning
death by suffocation - primary cause of death hypoxia
Near drowning
survival of drowning (w/ unconsciousness/ inhalation of water)
can lead to complication, even death
Secondary drowning
death caused by chemical and biological changes in the lungs after a near drowning incident
Wet drowning
primary cause of death oxygen deprivation (hypoxia)
dry drowning
rare (10-15%)\
can lead to death through hypoxia
Secondary drowning
occurs after a near drowning incident
can occur up to 72hrs
caused by water damage to inside of lungs and alveoli
