Hypothermia in operating room ( risk factors, complication, and prevention)

1. THERMOREGULATION &
HYPOTHERMIA

2. CORE TEMPERATURE
The core temperature of the human body is
37°C.
The core of the human body includes the organs
of the thorax, abdomen and the head.
This is where the vital organs are located.
Their enzyme system must operate in optimum
conditions.
The periphery of the body can withstand some
deviation from the core temperature

3. HEAT LOSS AND HEAT GAIN
• Conduction
• Metabolic activity (e.g. when
muscle move)Heat gain
• conduction and radiation
• Evaporation
• Humans can also affect their
body temperature by changing
their behavior e.g. wearing
different clothes, seeking shade
Heat loss
The body must balance its heat
budget

4. MAINTAINING THE BODY
TEMPERATURE

5. Core body
temperature
>37°C
Thermoreceptors
Hypothalamus
Sweat glands
increase
secretion
Muscles
Reduce activity
Muscles of skin
arteriole walls relax
Less heat
generated
 More water
covers the skin.
More
evaporation
 Skin arteries
dilate
 More blood to the
skin.
 More radiation
& conduction of
heat
Return to 37C
Body loses heat
Negativ
e
feedbac
k

6. Core body
temperature
<37°C
Thermoreceptors
Hypothalamus
Sweat glands
decrease
secretion
Muscles
shivering
Muscles of skin
arteriole walls
constrict
Body gains heat Body loses less
heat
Return to 37C
Negativ
e
feedbac
k

7. TEMPERATURE
HOMEOSTASIS
IN HUMANS

9. Objectives
To know
Definition
Contributing factors for hypothermia
Potential complications related to
hypothermia
When and how to measure a patient’s
temperature
Methods of preventing hypothermia and
when to use them

10. What is hypothermia ?
 Hypothermia is a dangerous drop in
body temperature below 35C (95F).

11. CONTRIBUTING FACTORS
Type and duration of the surgical
procedure
Type and duration of planned
anesthesia
Ambient operating room temperature
Procedure-related devices

12. PATIENT-RELATED FACTORS
Age
Sex
Low body-surface area or weight
Cardiac situations
Preexisting medical conditions
Hypotension
History of organ transplant
CONTRIBUTING FACTORS

13. Question
When should you monitor the patient’s
temperature?
a) Every procedure
b) Procedures longer than 15 minutes
c) Procedures longer than 30 minutes
d) Procedures longer than 60 minutes

14. TEMPERATURE
MEASUREMENT
Measure and monitor
Who
When
Everyone- especially those
undergoing long procedures.

15. POTENTIAL
COMPLICATIONS
Evidence supports that hypothermia can
lead to
Myocardial events
Increased peripheral vascular resistance
Left shift of the hemoglobin-oxygen
saturation curve
Reversible coagulopathy (platelet
dysfunction)
Postoperative protein catabolism and
stress-response-altered mental status
Impaired renal function

16. POTENTIAL
COMPLICATIONS
Postoperative pain
Decreased drug metabolism
Pressure ulcers
Poor wound healing
Incidence of infection

17. POTENTIAL
COMPLICATIONS
There is conflicting evidence about
whether hypothermia contributes to
Surgical site infection
Blood loss
Wound complications
Mortality
Increased length of hospitalization
Increased length of time in the PACU

18. Question
Do you apply a warming device, in
addition to a blanket, to your patients
before the patient arrives in the OR?
 Yes
 No

19. HYPOTHERMIA PREVENTION
METHODS
ACTIVE WARMING METHODS
Increasing the ambient room temperature
Radiant warming
Forced-air warming
– Hosing—do not use hose without the blanket
manufactured for the forced-air warming device.
– Tenting—follow the manufacturer’s written instructions
for use
Water-filled mattress
Circulating water garment
Warmed irrigation fluids
– Measure fluid temperature when administered

21. Electric warming blankets
Carbon fiber blankets
Resistive polymer blankets
Electric heating pads
Thermal exchange chambers
Negative pressure warming systems
HYPOTHERMIA PREVENTION
METHODS

22. PASSIVE WARMING METHODS
Insulating devices
Cotton blankets
Surgical drapes
Plastic sheeting
Blankets or garments made of
reflective composite fabric
◦ Space blankets
HYPOTHERMIA PREVENTION
METHODS

23. ANESTHESIA REGULATED METHODS
Warmed IV fluids
◦ use technology designed for this purpose
Warmed anesthesia gases
HYPOTHERMIA PREVENTION
METHODS

24. When hypothermia is identified on
admission to the PACU, methods of
warming should be initiated:
forced-air warming
radiant warming devices
passive thermal measures
ambient room temperature at or above
24° C [75.2° F]
warmed IV fluids
warmed oxygen
HYPOTHERMIA PREVENTION
METHODS

25. Thank you …….

26. Questions !!