Tourniquet and its effects

1. SYSTEMIC EFFECTS
OF TOURNIQUET
PRATEEK GUPTA
PG (1ST YEAR ANESTHESIA)

2. TOURNIQUET
• Constricting or compressing device used to
control venous and arterial circulation to an
extremity for a peroid of time
• Pressure is applied circumferentially upon the skin
underlying tissues of the limb
• Pressure is transferred to the vessel walls,
occluding them

3. HISTORY
• Jean Louis Petit coined the word “Tourniquet” from the French
word tourner (to turn) in 1718 when he used them for lower limb
amputations to reduce blood loss.
• In 1873 , Johan Friedrich August Von Esmarch introduced flat
rubber tube wrapped repeatedly around the limb as tourniquet
• In 1904 Harvey Cushing introduced pneumatic tourniquet to limb
surgery

4. USES
1. Extremity surgery to reduce blood loss and provide good
operating conditions,
2. Intravenous regional anaesthesia,( Biers block )
3. Intravenous regional sympathectomy in the management
of complex regional pain syndromes and
4. Isolated limb perfusion in the management of localised
malignancy
5. Control bleeding in traumatic cases

5. TYPES OF TOURNIQUET
• NON PNEUMATIC tourniquet
• PNEUMATIC tourniquet
 Non automatic
 Automatic

6. NON PNEUMATIC
• It is permissible only in exceptional circumstances.
• Pressure exerted by them on underlying tissue is
unknown.(Adult up to 900mm of Hg , children up to 1015
mm of Hg ).
• Esmarch bandage can be autoclaved ( if rolled properly
with cloth between each layer.
• Thus in sterile situation it can be used ( only a few
pneumatic cuff can be autoclaved )

7. PNEUMATIC
• Are based on same principles of blood pressure cuffs but
they are stronger.
• pneumatic tourniquets consist of three basic components:
1. CUFF, similar to a blood pressure cuff,which is wrapped
around a patient's limb and then inflated
2. COMPRESSED GAS SOURCE
3. PRESSURE GAUGE, designed to maintain pressure in the cuff
at a set value.

8. NON AUTOMATIC
• There is no automatic compensation for leak in the
system so regular check is required.
• Regular check on pressure in cuff
• Hand pump is small so it is difficult to raise pressure
above systolic pressure rapidly thus it can causes
venous engorgement

9. AUTOMATIC
• In this type of tourniquet ,there is constant supply
of gas to compensate any leak in system.
• Inflation of the cuff is very rapid and controllable
thus essentially eliminating the chance of venous
engorgement.

10. CONTRA-INDICATIONS
• Peripheral arterial disease.
• Severe crush injuries.
• Sickle cell disease( if tourniquet must be used , the
limb must be exsanguinated thoroughly before
inflation of cuff)

11. CONTD…
• Severe infection
• Malignant tumor
• Proven or suspected DVT

12. PRECAUTIONS
• Apply few layer of orthopaedic wool or towel at tourniquet
site.
• Choose correct size of cuff.
• Express all air from it.
• Snugly wrap the pneumatic cuff around the limb.
• Ensure that connecting tube lies on the outer aspect of limb
pointing proximally.
• .

13. • Must only be placed around upper arm and thigh
(exception – digital tourniquet). b/c these are the
only site where there is sufficient bulk to distribute
the pressure in the cuff evenly.
• Elevate the limb for 5 min. or exsanguinate the limb
by applying the esmarch bandage
• Must not be placed around forearm ,leg ,wrist
,ankle.

14. SIZE OF CUFF
• According to AHA, if WIDTH of cuff should be
 20% greater than the diameter of upper arm
 40% of the circumference of the thigh or 8 inch (20
cm)
 pressure in them need only be little above systolic
pressure, to maintain bloodless field.
• LENGTH
 10 cm in arm ,
 15 cm in thigh or larger for bigger limbs
• Better to increase the size of cuff than pressure

15. • The tourniquet cuff should overlap at least 3 inches
but not more than 6 inches. Too much overlap
causes increased pressure and rolling or wrinkling
of underlying soft tissue.
• Too small overlap compromises effective tourniquet
inflation and can result in unexpected release or
inadequate constriction.

16. • If narrow cuff is used high pressure is needed to occlude the
artery.
 tissue immediate beneath may be submitted to excessive
damaging pressure
• Curved/conical/contoured tourniquet greatly decreases pain

17. LIMB OCCLUSION PRESSURE
• LOP is the pressure in the cuff at which the
arterial pulse distal to the tourniquet disappears
• the distal blood flow which denotes the arterial
pulse is assessed using a DOPPLER PROBE.
• LOP is usually higher than the pressure that is
actually transmitted to the extremities and
• is also dependent on the circumference of the
limbs. This explains why LOPs for a thigh is higher
than that for an arm

18. • Common practice is to either use fixed pressures
(250mmHg for upper limbs and 300mmHg for
lower limbs) or
• inflate by a certain fixed pressure above systolic
blood pressure (SBP) (100mmHg above SBP for
upper limbs and 100-150mmHg for lower limbs).
• These practices SHOULD NOT BE followed as
these do not take into account the AGE in both
and the BP of the patient in the former technique
This can lead to over-inflation, especially in
younger patients as their SBP can be much lower.

19. AORN GUIDELINES
• Recommend that the tourniquet is inflated intraoperatively to a
pressure higher than the LOP; a safety margin is added to cover
intraoperative fluctuations in arterial pressure.
• LOP is <130 mm Hg then 40 mm Hg is added,
• if LOP is 131–190 mm Hg, 60 mm Hg is added and
• if LOP is >190 mm Hg, 90 mm Hg added .
• So a young, slim, normotensive adult may require a cuff pressure
<200 mm Hg.

20. DURATION
• a period of 1.5–2 hr in a healthy adult, which corresponds to
the point at which muscle ATP stores are depleted. (3 hours
being the absolute max)
• there is an approximate 3-fold increase in the risk of
neurological complications for each 30 min increase in
tourniquet time.

21. • If the duration of surgery exceeds the maximum safe
inflation time, the tourniquet should be deflated for 5-10
minutes for every 30 minutes of infaltion.
• This allows metabolic waste products to be removed and
oxygenated blood to perfuse the limb. and this seems to
correspond to restoration of muscle ATP levels.

22. • The limb should be exsanguinated by elevating and
using an Esmarch bandage or tourniquet
exsanguinators (S-MART)from the distal end to the
proximal end prior to inflation. It helps in
i. establishing a clear operating field,
ii. reducing overall blood loss, and
iii. reducing the risk of microemboli at the time of release.
iv. Minimises pain
• It results in autotransfusion of blood from the
peripheral circulation into the central circulation.
• The optimal timing and angle of elevation for
maximal exsanguinations of arm is 5 min at 90° and
for leg is 5 min at 45°.

23. • Adequate padding should be done at that site. Various
types of skin protection padding are available such as the
• Soffban skin protection (BSN Medical, Melbourne,
Australia),
• Atlantech skin protection drape (Atlantech Medical
Devices, Harrogate, UK),
• Velbands, etc. Velbands were found to be safe and cost-
effective skin protection beneath the tourniquet.
• Two layers of orthopaedic wool

24. • Any solution applied to the skin must not be allowed to run
underneath the tourniquet as it may lead to skin burns.
• A circumferential adhesive backed plastic drape applied just
distal to the tourniquet can help in preventing this.

25. Brenner’s ten’s rule

26. ESMARCH
• Elevate the limb
• Wrap the esmarch bandage around the limb, starting at
hand or foot and working proximally. Tips of toes and fingers
and heel can be left free.
• Fully stretch each turn of esmarch bandage before applying
it to the limb.
• Overlap each turn of bandage by ½ inch or 1.25 cm.
• Extremity is wrapped till 2.5 – 5 cm to tourniquet , to avoid
slipping of tourniquet distally

27. PHYSIOLOGICAL EFFECTS IN A LIMB
• progressive cellular hypoxia, acidosis, and cooling
• Decreased pH (<6.5),
• Decreased pO2,
• Increased pCO2,
• Increased K+,
• Increased lactate, occur progressively.
• Tourniquet-induced hypertension. The onset is analogous
to the onset of tourniquet pain.
• Tissue edema develops if time exceeds 60 min.
• After deflation, the return of circulation leads to the
development of the reperfusion injury.

28. HEMATOLOGICAL EFFECTS
• A/W hypercoagulable state that is due to increased
i. platelet aggregation and
ii. stimulation of coagulation factors
• Caused by tissue damage and catecholamines released in response to
pain from surgery and the tourniquet application

29. • There is a brief period of increased fibrinolytic activity
• Release of tissue plasminogen activator, activating the anti-thrombin
III and thrombomodulin — protein C anticoagulant system after the
deflation of the tourniquet.
• This acts as one of the contributors in post tourniquet bleeding.
• The increase in fibrinolysis is maximal at 15 min and returns to
preoperative levels within 30 min of tourniquet release
• This enhanced fibrinolysis may play a protective role in deep vein
thrombosis development.

30. CVS CHANGES
• Cardiovascular features are related to all stages of tourniquet use,
from exsanguination to inflation, maintenance and deflation.
• Limb exsanguination and subsequent tourniquet inflation increase
blood volume and systemic vascular resistance.
• CVP increases by up to 14 – 15 cm OF H2O and blood volume by up to
(~800 ml) following exsanguination of both legs.
• The changes in CVP and BP may be transient or may be maintained
until tourniquet release.
• 2nd rise in Heart rate, systolic, and diastolic pressures may increase
after 30-60 min of tourniquet inflation due to ischemia and
tourniquet pain

31. • Ketamine, dexmedetomidine, magnesium sulfate, clonidine, and
remifentanil infusion.
• Tourniquet deflation leads to the redistribution of the circulating
volume back into the limb and post ischaemic reactive
hyperaemia.
• Metabolites accumulated in the limb are released into the
systemic circulation,leading to a transient fall in arterial blood
pressure and central venous pressure.
• Cardiac dysrhythmias rarely occur.

32. CNS
• The rapid increase in FE’CO2 after tourniquet deflation increases the
cerebral blood flow which peaks at around 2 minutes and returns to
baseline within 10minutes
• This may prove detrimental by worsening the secondary brain injury
in patients with increased intracranial pressure such as that seen in
head injuries.
• Maintaining normocapnia can prevent this increase in cerebral blood
flow during deflation
• Middle Cerebral Artery flow increases after tourniquet deflation,
related to the increased ETCO2

33. RESPIRATORY EFFECTS
• Tourniquet inflation has minimal effects on the respiratory system
• Deflation leads to an immediate increase in ETCO2 which peaks at 1-3
minute. It usually returns to baseline within 10-13 minutes.
• The ETCO2 increases by 0.75 – 18 mmHg– the LL >UL and men
>women, because of a man’s greater muscle bulk
• This is seen as increase in minute ventilation in spontaneously
breathing patients.
• In controlled ventilation, increasing the minute ventilation for 5
minutes prior to deflation keeps the increase in carbon dioxide levels
to a minimum.

34. TEMPERATURE CHANGES
• Core body temperature gradually increases as the available surface
area for heat loss decreases resulting in less heat transfer from the
central to the peripheral compartment.
• Deflation leads to a transient fall in core temperature due to the
redistribution of body heat and hypothermic blood from the ischemic
limb.
• Maintenance of core body normothermia during surgery reduces this
decline in temperature
• In children the temperature may rise by as much as 1 – 1.7OC After
cuff deflation, a “redistribution hypothermia” may occur as the cold
extremity is reperfused

35. DRUG KINETIC
• Tourniquet inflation isolates the limb from the rest of the body,
altering the volume of distribution, sequestering drugs in the limb (if
given before inflation), or preventing them from reaching the limb (if
given after inflation)
• To prevent postoperative infection, prophylactic antibiotics need to
reach the tissues in adequate concentrations before tourniquet
inflation – at least 5 minutes is required

36. NERVE DAMAGE
• These occur as a result of ISCHAEMIA and MEHCANICAL COMPRESSION
• The RADIAL NERVE > ULNAR NERVE > MEDIAN NERVE in the upper limb
• The SCIATIC NERVE in the lower limb are most commonly involved and
• Large diameter nerve fibres are more commonly affected.
• Supra-systolic pressure leads to development of a reversible
physiological conduction block in both motor and sensory nerves
approximately 15 – 45 minutes after cuff inflation
•

37. • the nerve injury is maximum at the proximal and distal edges of the
cuff where the shear stress is greatest
• cuff causes intraneural microvascular abnormalities in the parts of
the nerve adjacent to the cuff.
• Edema results and leads to compromised tissue nutrition and axonal
degeneration. COMPRESSION is more responsible for this than
ischaemia.
• Excessive pressure distort the myelin sheaths which retract from the
nodes of Ranvier . This process continues as segmental
demyelination.
• This can last as long as 6 months, but permanent changes are rare
•

38. PARALYSIS SYNDROME
• Describe by MOLDAVER in 1954
• It is caused by pressure rather than ischemia.
• At the level of tourniquet
• Stimulation distal to block may still produce contraction

39. CLINICAL FEATURES
 Motor paralysis with hypotonia or atonia without atrophy.
 Sensory dissociation ( touch , position, vibration , position sense is
lost/ pain sensation intact even hyperalgesia).
 Colour, temperature and sympathetic function are normal.
 Peripheral pulse is normal

40. CAUSES
• EXCESSIVE PRESSURE
• INSUFFICIENT PRESSURE – congestion and haemorrhagic infiltration of
nerve
• Application for too long
• Application without consideration of local anatomy

41. कनक
Recovery from paralysis takes up to three month.

42. PREVENTION OF NERVE DAMAGE
• Tourniquets use only recommended time.
• Check accuracy of the pressure.
• Effective pressure to achieve limb occlusion pressure.
• Use a cuff that properly fits the extremity.
• Don’t apply over the peroneal nerve or ulnar nerve.

43. MUSCLE INJURY
• Muscle is more susceptible to ischemic damage than nerve.
• Histological evidence of muscle damage is evident 30–60 min after
tourniquet inflation
• Muscle injury is caused by ischaemia beneath and distal to the cuff.
• combination of ischaemia and mechanical deformation of the tissue.
• The extent of the damage is related to the duration of the ischaemia

44. • Creatine phosphate is depleted by 2 hrs and the ATP supply is
exhausted by 3 hrs.
• Lactate and K+ concentrations and the PaCO2 increase with increasing
duration of ischaemia
• Intracellular pH decreases – a pH of 6.0 is reached by 4 hours.
• Intravenous pH in the limb decreases and a pH of 6.9 corresponds to
the fatigue point of muscle.

45. After 2 hours at 200 – 300 mmHg, histological changes
e.g. :inflammatory cells, focal necrosis, regional necrosis and hyaline
degeneration
• significant increases in XANTHINE OXIDASE activity in both local and
systemic blood
• Xanthine oxidase contributes to injury of skeletal muscle,
myocardium, kidneys and lungs after ischaemia and reperfusion
• Rhadomyolysis (very rare)

46. POST TOURNIQUET SYNDROME
• The combined effect of muscle ISCHAEMIA, OEDEMA and
MICROVASCULAR CONGESTION
• Following release of tourniquet there is immediate swelling of
tissues (reactive hyperaemia , inc. capillary permeability ).
• Swelling is much more severe when tourniquet time is more than
2 hrs.
• Longer the period of ischemia & older the patient increase the
chance of post tourniquet syndrome.

47. • Puffiness of skin and fingers ( smoothening out of normal skin
crease)
• Stiffness of joints
• Colour change ( pale on elevation, congested when dependent)
• Subjective sensation of numbness
• Weakness of muscle without real paralysis

48. PREVENTION
• Do not extend the tourniquet time unnecessarily
• Ensure good hemostasis
• Elevate the limb after operation
• Encourage the patient to perform active movement
• it is recommended that the limb be reperfused periodically to allow
for metabolic recovery of the muscle and maintenance of ATP levels
• Drug history ( steriods in RA, aspirin) should be taken
• Evidence of arterial calcification

49. COMPARTMENT SYNDROME
• A swollen and oedematous ischaemic limb in conjunction with a
reperfusion hyperaemia may also lead to a compartment syndrome
• very rare.
• Tense skin,
• swelling, weakness, parasthesia.
• Absent pulse – irreversible paralysis.

50. VASCULAR
• Rare
• They are usually associated with peripheral vascular disease and
fractures of atheromatous plaques by pressure
• plaque dislodgement
• thrombosis due to lack of blood flow

51. SKIN INJURY
• Pressure necrosis and shearing have been described with
pneumatic tourniquets because of inadequate padding or
improper application.
• Chemical burns have been reported with alcohol based
cleansing solutions held against the skin under pressure
• Friction burns from the movement of a fully inflated tourniquet
over bare skin

52. HEMATOMAS/BLEEDING
• Because of tourniquet inflation, bleeders may not be identified intraoperatively.
• Once the tourniquet is released, a haematoma may develop or there may be a
potential for acute blood loss superimposed on the haemodynamic changes of
tourniquet release
• tourniquet release for haemostasis has actually been shown to increase bleeding
• Haematomas, arterial injuries and a compartment syndrome may all result in a
delayed return of blood flow after tourniquet release

53. TOURNIQUET FAILURE
• Bleeding may occur despite a properly applied and inflated
tourniquet, in a patient with non-calcified vessels.
• This is the phenomenon of tourniquet ooze.
• Blood bypasses the tourniquet through the medulla of the humerus
or femur. It typically starts about 30 minutes after tourniquet inflation
.
• Increasing the tourniquet pressure does not help

54. • Other causes of inadequate haemostasis include arterial and
venous leakage due to
i. Inadequate pressure,
ii. Calcified,
iii. Incompressible vessels and
iv. Inadequate exsanguination

55. TOURNIQUET PAIN
• Approximately 30 – 60 minutes after tourniquet inflation, heart rate and
blood pressure increase
• An awake patient will complain of a vague, dull pain that be-comes so
severe as to be unbearable.
• It will occur despite an adequate sensory level.
• The incidence increases with increasing age and duration of surgery, and
with lower limb surgery.

56. • The pain is probably mediated by the unmyelinated, slow conducting
C fibres .
• The A-delta fibres are blocked by mechanical compression after
about 30 minutes, while the C fibres continue to function.(The skin
under the inflated tourniquet provides the continuous stimulation of
these Cfibres)
• Tourniquet pain is a problem even in patients with an effective
central neuraxial blockade.

57. • The addition of adrenaline to the local anaesthetic, clonidine or
morphine
• The onset of “tourniquet pain” has been delayed by the
application of EMLA cream to the tourniquet site and by
subcutaneous infiltration of local anaesthetic

58. • Rare episodes of PE have been reported during leg
exsanguination, both after inflation and following deflation.
• These can occur more commonly in patients with a history of
deep vein thrombosis and atherosclerotic vessels

59. TOURNIQUET SAFETY
• BEFORE APPLYING
• Aneroid pressure gauges should be checked against
calibration devices.
• The whole system should be leak proof.
• There should be no fluctuations in pressure with time.
• Thorough visual inspection should be carried out prior to
use.
• Cuff width AND Length should be appropriate to the size of
the patient.

60. • HIGH RISK PATIENTS ARE -morbidly obese patients, those who have
had a prolonged immobilisation prior to surgery, patients with deep
vein thrombosis, isolated limb malignancies and infections, patients
with left ventricular dysfunction.
• Tourniquet inflation time and pressure should be kept to a minimum
and should relate to the patient’s age and comorbidities.
• Surgeons should be kept informed of the inflation times.
• Appropriate documentation of tourniquet usage should be recorded in
the patient’s notes.

61. • DURING USE•
• Pressure gauges should be continually monitored
• Cuffs should be placed at a point of maximum circumference of the
limb. •
• Adequate padding, avoiding folds,
• Once applied, the cuff should not be rotated into a new position. •
• Skin cleaning solutions should not be allowed to seep or under the cuff.

62. • AFTER USE: •
• Reusable cuffs should be thoroughly cleaned to prevent cross
infection.
• The affected limb should be thoroughly inspected.