physical hazards at the workplace Flashcards
what are the different types of hazards in occupational medicine ?
physical chemical biological mechanical psychosocial
what is the heat balance equation ?
body temp = M+R+c-E metabolism radiation conduction evaporation
what is heat stress determined by ?
air temperature
air movement
amount of radiant heat
humidity
what are the different types of occupational exposures to heat ?
hot environment
direct exposure to the sun
what are the different types of heat disorders ?
heat strokes heat exhaustion heat cramps heat syncope skin disorders
what are some risk factors of heat disorders ?
extremes of age alcohol abuse dehydration obesity sleep deprivation lack of acclimatisation history of heat strokes
what are some medical conditions that increase the risk factors for heat disorders ?
cardiac disease vascular disease hypotension disease of the CNS Extensive skin disease febrile illnesses thyrotoxicosis
what medications increase the risk of heat disorders ?
- sympathomimetics like cocaine and amphetamine
- anticholinergic drugs
- drugs that decrease cardiac contractility
- drugs that cause volume depletion
- lithium drugs
how does lithium have an affect on the occurence of heat disorders ?
lithium interferes with hypothalamic thermoregulatory mechanisms
what is the manifestation of heat strokes ?
cerebral dysfunction
altered mental status
what are the two types of heat strokes ?
classic type
exertional
what is the difference between a classic type and an exertional type of heat stroke ?
classic is when extreme heat exposure occurs to a susceptible individual
an exertional one happens when a lot of effort is exerted inn a hot environment to an unacclimitazied individual
what are the three cardinal signs of a heat stroke ?
- red hot dry skin “generalized anhidrosis”
- CNS manifestation
- Core body temp more than 41.1
what is the treatment for heat strokes ?
aim is to control the body temp within one hour
move to a shady cool place
entire body should be sprayed with cool water along with a fan
chlorpromazine can be used to control the shivering
what is acclimatization ?
gradual, controlled exposure to heated environments of increasing intensity and duration to allow the body to adjust to heat
what is heat exhaustion ?
strenuous work and prolonged exposure to heat with insufficient salt and water intake
what are the signs of symptoms of heat exhaustion ?
1 .thirst or dehydration 2 .heat cramps 3. moist skinn 4 .temperature more than 38 but less than 41.1 5. loss of consciousness
what is the treatment for heat exhaustion ?
- place patient in a cool and shaded environment
- hydration of 1-2 litres over 2 to 4 hours
- saline or isotonic glucose solution should be given IV in more severe cases
what are heat cramps caused by ?
dilutional hyponatraemia caused by replacement of sweat losses with water alone
what is the treatment for heat cramps ?
relax the muscle and provide water and salt
what is a heat syncope ?
sudden unconsciousness results from volume depletion and cutaneous vasodilation with consequent systemic and cerebral hypotension
what is the clinical picture of heat syncope ?
- the skin is cool and moist and the pulse is weak
2. systolic BP is usually below 100mmhg
what is a heat rash ?
miliaria is caused by sweat retention resulting from obstruction of the sweat gland duct
how do dysbaric disorders happen ?
when moving too quickly from an area of high pressure to an area of low pressure can produce nitrogen gas bubbles in the body
what are the types of decompression sickness ?
type 1
type 2
type 3
what are the features of type 1 DCS ?
joint pain ( large joint)
skin rash “divers lice”
itching mottling rash
what are the features of type2 DCS ?
associated with fat embolism:
- spinal cord and brain disorders
- pulmonary chokes
- arterial gas embolism
what are the features of type 3 DCS ?
delayed dysbaric osteonecrosis
which is basically aseptic necrosis of the bone
what is the treatment for DCS ?
recompression with gradual decompression in hyperbaric chambers
what are the types of ionizing radiation ?
alpha and beta particles
gamma and Xrays
what are the types of non - ionizing radiation ?
ultraviolet
infrared
microwave
what is the cause of acute radiation syndrome ?
sudden exposure to a high dose of radiation
what is the clinical picture of ARS ?
- bone marrow syndrome (hematopoeitic syndrome)
2 .gastrointestinal syndrome - CV/ CNS syndrome
what is the most radiosensitive organ ?
the bone marrow
what is the primary cause of death in ARS ?
destruction of the bone marrow leading to infection and haemorrhage
what is the prognosis in ARS ?
if GI symptoms have developed recovery is unlikely
if the CNS or CV is involved then death will occur within a few days from exposure
what does chromic radiation dermatitis look like ?
- thin atrophic skin
- tenelgectasia
- pigmentation
- loss of sebaceous gland or 5. hair follicles and reduced sweating
what must PPE include to reduce exposure to radiation ?
lead equipped PPE
