Miscellaneous Monitors Flashcards
febrile definition
> 38 degrees C
hypothermia defintion
<36 degrees C
room temp
23 degrees C
what is the recommended room temperature for the OR
between 20-24 degrees C
what are the 6 temperature monitoring sites?
blood (swan) esophageal rectal nasal bladder skin/ axillary
which temp monitoring location is the best estimate of core temp?
swan ganz
which temp monitoring site is the most consistently reliable estimate of core body temp
esophageal
when is the esophageal temp probe less reliable?
open chest cases
when would the rectal temp probe be less reliable?
if rectum isnt clear
What is a good temp probe choice during open heart surgery?
nasal bc the chest is open so esophageal will not be accurate
what does the accuracy of the bladder temp probe rely on?
urine output being normal
what are the 4 causes of intraop temp loss?
IV fluids
vasodilation
blood products
volatile agents
how much does 1 unit of blood or 1 L of crystalloids decrease the mean body temp by?
0.25 degrees C
how does vasodilation cause temp loss?
redistributes heat from warm central compartments to cooler peripheral tissues
how dose the volatile agents cause temp loss?
interferes with hypothalamic thermoregulation
what blood products are stored at cool temps and should be given through a blood warmer?
PRBC
cryo
FFP
what blood product is not given through a fluid warmer?
platelets
4 adverse cardiovascular effects of hypothermia
platelet dysfunction/bleeding
decreased SV
bradycardia/arrhythmia
increased blood viscosity
for every 1 degree C drop in body temp the cerebral blood flow decreases how much?
5-7%
what is the adverse neurologic effect of hypothermia
increased cerebral vascular resistance
decreased cerebral blood flow
adverse renal effects of hypothermia
decreased GFR
impaired renal tubular function
adverse respiratory effects of hypothermia
respiratory depression
left shift of the HbO2 dissociation curve
adverse metabolic effects of hypothermia
decreased drug metabolism & delayed emergence
decreased wound healing
shivering
how much does shivering increase oxygen consumption?
five fold
what pts should we be extremely concerned with shivering?
pts with CAD
When is shivering more likely? 3
lower intraop temp
longer surgery
higher volatile agent
what are the two treatments for shivering?
warm the pt
demerol 25mg
4 types of heat loss in the OR (in order of most heat loss to least, with %)
radiation 60%
evaporation 20%
convection 15%
conduction 5%
radiation definition
losing heat to the colder temp of atmosphere (requires no contact)
60%