TORNIQUET and its applications over the different parts of body

Torniquet

1. TOURNIQUET PRESENTED BY- DR.ROUNAK PAHUJA (PG JR1 ORTHOPAEDICS)

2. TOURNIQUET The term TOURNIQUET was coined by Petit in 1718. DEFINITION- Tourniquet is constricting or compressing device used to control venous and arterial circulation to the upper and lower extremities for a period of time.

3. Image showing Tourniquet application:

4. Introduction: In many orthopaedic surgeries on the upper and lower limbs a bloodless field is important as it helps in the recognition of tissues and eliminates delay and trauma caused by repeated swabbing. To provide a bloodless field, blood must be removed from the limb and then prevented from re-entering it. Elevation of the limb and reflex vasoconstriction which follows these decreases the volume of blood within it but more complete exsanguination can be achieved by actively squeezing the blood out of the limb.

5. Functions: Promote optimum surgical conditions(creates a blood less field ) To control bleeding in life or limb threatening situations. To engorge vessels for venipuncture .

6. Parts of Tourniquet: Inflatable cuff Gas source (Nitrogen or air) Pressure display Pressure regulator Connection tubing

7. Shape of tourniquet: 1 .Curved Tourniquet 2. Straight Tourniquet

8. Shape of the cuff of Tourniquet-Curved tourniquets on conical extremities require significantly lower arterial occlusion pressures than straight (rectangular) tourniquets. The use of straight tourniquets on conical thighs should be avoided, especially in extremely muscular or obese individuals.

9. TYPES OF TOURNIQUET: Non-Pneumatic Pneumatic : 1. Non-automatic 2. Automatic

10. Non-Pneumatic A type of strap or rubber band that is wrapped around the extremity to exsanguinate the blood. The danger with non-pneumatic tourniquet whether straps or rubber bandage is that the pressure exerted by them on the underlying tissues is unknown.

11. EXSANGUINATION: The simplest way to remove most of blood from limb is to elevate the limb as vertically as possible for four minutes. Blood drains from the veins under the effect of gravity, and this is followed by reflex arteriolar constriction which makes the emptying more complete.

12. Exsanguination by Esmarch Bandage: Esmarch tourniquet is used in some areas and is the safest and most practical of the elastic tourniquets. It is applied in area where there is more muscle bulk for example in mid and upper thigh and Arm. The Esmarch tourniquet is applied in layers, one on the top of other; a narrow band produces less tissue damage than does a wide one.

13. Image showing how to apply a Esmarch Bandage :

14. Contraindications to exsanguination: Severe infections and tumor –In these expressive exsanguination must not be used to avoid dissemination. Proven or suspected Deep vein Thrombosis-In this fatal massive pulmonary embolism can occur.

15. Pneumatic: It is an air inflated cuff to constrict blood flow. A regulating device on the tourniquet machine that can control amount of cuff pressure. NON-AUTOMATIC : A non automatic pneumatic tourniquet consist of a pneumatic cuff, a hand operated pump and pressure gauge. The pressure in the cuff is known but there is no automatic compensation for leaks in the system.

16. Pneumatic: Automatic : In an automatic pneumatic tourniquet there is a constant supply of gas to compensate for any leaks in the system.

17. Site for Application: Tourniquet must only be placed around the upper arm or thigh. These are the only places where there is sufficient muscle bulk to distribute the pressure in the cuff evenly, and thus avoid local high pressure areas over tissues close to surface. Cuffs must not be placed around forearm,wrist or ankle.

18. TOURNIQUET PRESSURE: . For the upper limb: 50 to 100 mm of Hg higher than the systolic blood pressure (200-250 mm of Hg) . For the lower limb – Double than the systolic blood pressure (250-350 mm of Hg) . The correct pressure depends on the age of patient, blood pressure, and the size of the extremity. . Wide tourniquet cuffs are more effective at lower inflation pressure than are narrow ones.

19. TOURNIQUET TIME: Tourniquets must be applied for shortest possible time, compatible with surgery. The time may vary with the age of patient and the vascular supply of extremity. In an average healthy adult younger than 50 years of age, we prefer to leave the tourniquet inflated for no more than 2 hours. For upper limb- preferable time is 1 and half hour For lower limb – preferable time is 2 hour

20. Braithwaite and Klenerman’s modification of Bruner’s rules

21. Contraindication for use of tourniquet: 1.Peripheral arterial disease. 2. Severe crushing injuries. 3. Sickle cell Disease- Under anoxic condition the RBC sickle, blood viscosity increases , vessels become block and a severe episode of thrombosis and haemolysis , may occur, particularly on release of tourniquet. 4. Patient with past history of deep vein thrombosis and pulmonary embolism. 5.Patients with established Diabetic Neuropathy-There is ischemia due to arteritis/ atheroscelorosis .

22. Dangers of a Tourniquet The dangers from the use of tourniquet can result: 1.From the process of exsanguination 2.From pressure on the tissue under the tourniquet 3. From Ischemia 4. From bleeding after the closure of wound and from failure to remove tourniquet at the end of surgery.

23. Dangers from exsanguination : Exsanguination by elevation is not hazardous, but there are risk when it is achieved by compression. Frictional shearing forces from a tightly applied Esmarch Bandage can damage the skin, especially when it is weakened by conditions such as Senility, Rheumatoid arthritis, steroids or Ehler danlos syndrome. The ends of fractured bones,bone screws or foreign body may damage skin or soft tissue if the bandage is applied tightly. Nerves which lie subcutaneously can be damaged unless protected by additional padding.

24. In the elderly patient a tourniquet should be applied to only one limb at a time. Effective exsanguination of both lower limb will result in 15% of circulating blood volume being forced back into remaining circulation, this extra cardiac load cannot be tolerated by elderly or unfit patient.

25. Dangers from the Pressure in the Tourniquet Cuff: Most tourniquet cuffs need a layer of foam padding under them to protect the skin from pinching and abrasion as the cuff is inflated. Ocassionaly walls of arteries are stiffened by calcium deposits which cannot be compressed by normal cuff pressures. If the pressure is increased there is risk that vessel wall will fracture and the blood supply to the limb will be damaged permanently.

26. Even if the pressure in the cuff is normal, local damage under the cuff can occur if the skin is fragile, the bone is irregular, or normal padding from muscle or fat is absent for example in cachexia, severe rheumatoid arthritis, and poliomyelitis. In these situations, extra padding under the cuff must be used. If the pressure in the cuff is higher than necessary, normal skin, muscles, and nerves are at risk.

27. Muscle is the tissue most likely to suffer permanent damage,but the most severe functional disability results from damage to nerves. When a nerves sustains local injury from pressure the effect is seen over the whole area distal to the site of injury, supplied by that nerve. The effect of injury to a muscle is restricted to that muscle and its action.

28. Dangers from bleeding after the closure of wound If a tourniquet is released before the wound is closed, any major source of hemorrhage can be identified and can be controlled. This may prevent the formation of haematoma jeopardising wound healing. With some surgery there is bleeding from bone which cannot be stopped until a firm dressing is applied.In these cases it is better to insert a drain and keep the cuff inflated until the dressing is secure.

29. Complications: Asymptomatic/symptomatic pulmonary embolism. Chemical burn from solutions seeping underneath the tourniquet. Superficial slough/abrasion of skin. Tourniquet paralysis syndrome. Post Tourniquet Syndrome. Compartment Syndrome. Rhabdomyolysis . Vascular complications.

30. TOURNIQUET PARALYSIS SYNDROME : The tourniquet paralysis syndrome is caused by pressure rather than ischemia: It is described by: 1.Motor paralysis with hypotonia or atonia 2.Sensory dissociation 3.The colour and temperature of skin are normal as sympathetic function is not affected 4.Peripheral pulses are normal.

31. POST TOURNIQUET SYNDROME: Following the release of a tourniquet there is immediate swelling of tissue due to reactive hyperaemia and increased capillary permeability to fluid and protein. If this swelling is severe and allowed to persist the condition merges into Post tourniquet syndrome. The Post tourniquet syndrome is probably due to ischemia and its duration.

32. Post tourniquet syndrome consist of the following :- 1.Puffiness of hand and fingers. 2. Stiffness of joints in hand. 3.Colour changes in hand which is pale when elevated and congested when dependent. 4.Sensation of numbness. 5.Weakness of muscle in hand and forearm without real paralysis.

33. Prevention of Post tourniquet syndrome: To decrease the congestion of tissues and to minimise hematoma formation at the operative site: 1.Select the correct surgery for each patient. 2.Avoid wasting time by careful pre-operative planning of surgery. 3.Donot extend the tourniquet time unnecessarily. 4. Elevate the limb after the surgery. 5.Encourage patient to perform active movements of pertinent limb.

34. Pediatric Tourniquet: Pediatric patients need pediatric tourniquets because infants and children have smaller limb circumferences and limb lengths, different mass of muscle and other soft tissues, and different physiological characteristics such as blood pressure and heart rate. To ensure safe and effective tourniquet use in these populations, it is important to use personalized tourniquet cuffs and personalized tourniquet pressures.

35. Personalized pediatric tourniquet cuffs: Personalized tourniquet cuffs designed for pediatric patients are available in a variety of sizes and can have cylindrical or a variable contour design. Multiple cuffs widths and lengths are available for neonatal to adolescent patients. For adolescent patients with tapered limbs, variable contour designs are also available.

36. These cuffs are designed to better match patient’s limb size and shape and thus provide more efficient application of cuff pressure to the limb, allowing lower and safer tourniquet pressure.

37. Image showing cylindrical pediatric cuffs:

38. Image showing contour pediatric cuffs:

39. Matching limb protection sleeves are also available to improve safety by protecting skin underneath the tourniquet cuffs during tourniquet use.

40. Personalized pediatric tourniquet pressure: Personalized tourniquet pressure reduce the risk of tourniquet related injuries by enabling the use of lower tourniquet pressure levels and lower tourniquet cuff pressure gradients to the patient. This is accomplished by measuring each patient’s Limb Occlusion Pressure[LOP] and setting a tourniquet pressure for that patient based on LOP.

41. Limb Occlusion Pressure: Limb occlusion pressure can be defined as the minimum pressure required, at a specific time in a specific tourniquet cuff applied to a specific patient’s limb at a specific location, to stop the flow of arterial blood into the limb distal to the cuff. Many studies published in clinical literature have shown that higher tourniquet pressures are associated with higher risk of tourniquet related injuries.

42. When a tourniquet is used in surgery, the best practice is to use the lowest tourniquet pressure that is safely possible and to use a tourniquet cuff that is designed to produce the lowest pressure gradient. LOP is personalized to each individual patient and each individual surgical procedure. Setting the tourniquet pressure on the basis of LOP minimizes the risk of tourniquet related injuries.

43. Pressure gradient beneath a tourniquet cuff: Pressure gradient is defined as variation in pressure applied by pressurized tourniquet cuff to the underlying limb across the width of the cuff. It is affected by tourniquet pressure level and by the design and the width of pressurized cuff.

44. Setting tourniquet pressure based on Limb Occlusion Pressure: The best practice for setting tourniquet pressure is to set a personalized pressure that is based on Limb occlusion pressure. The currently established guideline for setting tourniquet pressure based on LOP is that additional safety margin of pressure is added to measured LOP, to account for physiologic variation and other changes that may be anticipated to occur normally over the duration of surgical procedure.

45. A safety margin of 40-100 mm hg above the LOP has been suggested. Typically the safety margin is lower for lower LOP levels and higher for higher LOP levels.

46. Measurement of LOP: We can measure LOP manually by palpation or Doppler ultrasound, or automatically using a distal photoplethysmographic sensor or a dual purpose tourniquet cuff.

47. Automatic measurement of LOP Using distal photoplethysmography probe:

48. An automatic plethysmographic system built into the tourniquet instrument that measures LOP in about 30 seconds at the beginning of operative procedure has been developed and is widely used in surgical settings. The automated system incorporates a probe placed on digit of patient’s operative limb. The probe detects the presence of arterial pulsations in the limb distal to the tourniquet cuff as an indicator of arterial blood flow past the cuff and into the distal limb.

49. By automatically inflating the tourniquet cuff in predetermined steps having consistently defined durations, the minimum cuff pressure at which arterial blood flow past the cuff is stopped can be accurately determined. This cuff pressure is patient’s personalized limb occlusion pressure.

50. Manual measurement of LOP using a Doppler ultrasound One technique for manual measurement of LOP based on monitoring arterial pulsations as an indicator of arterial blood flow is as follows: tourniquet cuff pressure is increased by an operator slowly from zero while monitoring arterial pulsations in the limb distal to the cuff until the pulsations can no longer be detected; the lowest tourniquet cuff pressure at which the pulsations can no longer be detected can be defined as the ascending LOP. A second manual technique is that an operator can slowly decrease tourniquet cuff pressure while monitoring to detect the appearance of arterial pulsations distal to the cuff; the highest pressure at which arterial pulsations are detected can be defined as the descending LOP.

51. Automatic measurement of LOP using a dual-purpose tourniquet cuff: