2. History
• Early Romans reduced blood loss by use of materials
like narrow bands during amputations.
• Jean Louis Pettie coined the term which in French
means to “turn”.
• Ambrose Perri - Tourniquet in Surgery
• John Von Esmarch - Esmarchs Tourniquet made of
rubber bandage.
• Harvey Cushing - Pneumatic Tourniquets
8. ROLE OF TOURNIQUET IN
SURGERY
• Promotes blood less surgical field.
• Reduces Blood Loss.
• Facilitates identification of structures.
• Reduces the operating time.
• Reduces Complication.
9. PRINCIPLES OF
APPLICATION OF
TOURNIQUET
• Pressure and time must be recorded.
• Care to be taken that disinfectant does not pass
under the Tourniquet. Can be prevented by
applying plastic drapes under the Tourniquet.
• Constant reminder of time.
10.
11. APPLICATION OF
TOURNIQUET
• Exsanguination of the limb- Tissue Compression.
• Elevation of Limb for 2 Min.
• Padding - Closely and Snugly applied padding
prevents skin trauma.
• Inflation has to be done rapidly.
12. AIM OF TOURNIQUET
APPLICATION
• To produce bloodless field at lowest pressure
1. The minimum pressure depends on - Limb size
2. Cuff size- 20 % the circumference of UL. 40 % the
circumference of LL.
• Amount of pressure to be applied
A. Arm : SBP + 50 - 75 mm of Hg
B. Lower Limb : SBP + 75- 100 mm of Hg or 2 x SBP
13. PATHOPHYSIOLOGY
Both systemic and local effects occur during
tourniquet usage.
Systemic effects are usually related to the inflation
and deflation of tourniquets.
Local effects are usually due to ischemia or direct
mechanical pressure.
14. SYSTEMIC EFFECTS -
CARDIOVASCULAR
EFFECTS• Clinically insignificant in healthy patient.
• Cardiac arrest and circulatory overload has been reported where
b/l thigh tourniquet were used.
A. During Inflation:
• Shift of blood to central circulation and increase in peripheral
vascular resistance.
• This is seen as a transient increase in SBP and CVP.
• After 30 - 60 min there is a second gradual increase in Blood
Pressure and Heart Rate - Tourniquet Pain
15. A. During Deflation :
• Redistribution of circulating volume back into the
limb and post ischaemic reactive hyperaemia.
• Metabolites accumulated in the limb are released
into the systemic circulation- Fall in BP and CVP.
• Studies have shown that Propofol can attenuate
this response because it can limit super oxide
generation.
16. RESPIRATORY
SYSTEM
• Tourniquet inflation minimal effect.
• Tourniquet deflation can lead to immediate increase in
end tidal concentration of CO2 which peaks at 1 minute.
• Returns to baseline after 10 minutes.
• Greater when a lower limb tourniquet is released.
• Deflation leads to an increase in cardiac output and the
hypercapnic venous blood from the ischaemic limb
causes the rise in ETCO2.
17. • Seen as increase in minute ventilation in
spontaneously breathing patient.
• In controlled ventilation increasing the minute
ventilation 5 minutes prior to deflation keeps the
increase in CO2 levels to a minimum.
18. CENTRAL NERVOUS
SYSTEM
• The rapid increase in ETCO2 after tourniquet
deflation increases the cerebral blood flow.
• Peaks at 2 minutes.
• Baseline within 10minutes.
• 50% increase in middle cerebral artery velocity
during this period.**
• Detrimental by worsening the secondary brain injury
in patients with increased intracranial pressure.
• Maintaining normocapnia can prevent this increase
in cerebral blood flow during deflation.
19. HAEMATOLOGICAL
CHANGES
• The effects on the haematological system are complex.
A. During Inflation :
• Initially overall state of hypercoagulability
• Pain due to surgery and the tourniquet itself release
catecholamines which may cause platelet
aggregation.
• Tissue compression from the application of Esmarch
bandages - Platelet aggregation
20. • Despite this hypercoagulable state - ****NO DVT****.
A. During Deflation :
• A brief period of reduced coagulation
• Tissue plasminogen activator is released cause of
ischaemic effects.
• Systemic fibrinolysis after the tourniquet is deflated.
• This transient fibrinolysis is one of the contributors in post
tourniquet bleeding.
21. TEMPERATURE
REGULATION
A. During Inflation :
• Core body temperature is gradually - decreased
heat loss from the affected limb.
B. During Deflation:
• Transient fall in core temperature due to the
redistribution of body heat.
• Hypothermic blood from the ischaemic limb
increases the fall in core temperature.
22. CHANGE IN
METABOLISM
• During Inflation : Minimal / No changes
• During Deflation :
• Reversed in 30 min
• After 1-2 hours of limb ischaemia, plasma
potassium and lactate concentrations increases.
• Arterial pH of the systemic circulation falls due to
the increased lactate and carbon dioxide from
the ischaemic limb.
23. LOCAL EFFECTS -
NERVE
• Supra-systolic pressure leads to a reversible
physiological conduction block in both motor and
sensory nerves approximately 15 – 45 minutes after
cuff inflation.
• Published evidence suggests ischaemia to be the
cause of such a conduction block .
• Mechanical compression seems to be more
responsible for the long lasting block than ischaemia.
24. • Morphological changes are seen in the large
myelinated nerves especially underneath the
proximal and distal edges of the tourniquet after
2 hours of inflation.
• This can last as long as 6 months, but
permanent changes are rare.
25. MUSCLE
• During Inflation :
• Progressive tissue hypoxia and hypercapnia.
• Energy stores are progressively consumed and finally
exhausted.
• Hypercapnia along with anaerobic metabolism -
development of intracellular acidosis.
• Inflation - short as 60 minutes can produce morphological
changes in mitochondria and local fibre necrosis.
• Ischaemia lasting longer than 2 hours can cause
microvascular injury in the muscle.
