Tourniquet in Orthopaedic Surgery

PART A: Parts / Types / Descriptions of Tourniquet (5 marks)

Definition

Types of Tourniquets Used in Orthopaedics

1. Pneumatic Tourniquet (Most widely used - Gold Standard)

• Cuff - The inflatable bladder that encircles the limb. Available in:
  • Straight cuffs (for cylindrical limbs)
  • Curved/contoured cuffs (for conical thighs - preferred over straight cuffs on conical thighs)
  • Cuffs of varying widths - wider cuffs eliminate blood flow at lower inflation pressures (Moore et al.)
• Pressure gauge / manometer - Displays the inflation pressure in mmHg
• Inflation tubing - Connects the cuff to the pressure source
• Pressure regulator / control unit - Allows setting and maintaining desired pressure
• Timer - Indicates duration of tourniquet inflation; essential for safety

• Applied over cast padding (Webril) - smoothly applied, avoiding wrinkles (wrinkles cause blisters, skin pinching, and necrosis)
• No more than two layers of padding (more padding significantly reduces actual transmitted pressure)
• Applied to the upper arm (near axilla) for upper limb or the thigh (proximal) for lower limb

2. Esmarch Bandage (Rubber Bandage / Elastic Bandage)

• Made of sheet rubber (Martin sheet) or elastic material
• Used primarily for exsanguination of the limb before tourniquet inflation
• Applied from fingertips/toes proximally to within 2.5-5 cm of the tourniquet
• Must NOT be used alone as a tourniquet around the upper arm - risk of nerve damage from uncontrolled local pressure
• Contraindicated in infected cases - elevation alone is used for exsanguination in such cases

3. Sphygmomanometer Cuff

• Used when a formal pneumatic tourniquet is unavailable
• Should be wrapped with gauze bandage to prevent slipping during inflation
• Less reliable than a dedicated pneumatic tourniquet

4. Forearm / Wrist Tourniquet

• Forearm tourniquet is safe and reliable for hand and distal procedures (25 minutes or less, or distal to wrist with regional block)
• Advantages over upper arm tourniquet:
  • Decreased local anesthetic dose required (nearly half)
  • Less tourniquet pain
  • Longer duration of sensory block
  • Prolonged postoperative analgesia

5. Digital (Finger/Toe) Tourniquet

• Examples: Rubber ring tourniquet, ForgetMeNot tourniquet (a beaded bracelet-type device)
• Used for minor finger/toe procedures
• Rubber ring tourniquets should NOT be used on digits as they can be forgotten under dressings - a critical safety hazard
• The ForgetMeNot device has a visible attachment to alert the surgeon

Pressure Guidelines (Campbell's Concepts)

PART B: Complications and Safety Precautions (5 marks)

Complications of Tourniquet Use

1. Tourniquet Paralysis

• Results from:
  • Excessive pressure
  • Insufficient pressure (causes passive venous congestion + hemorrhagic infiltration of nerve)
  • Tourniquet kept inflated too long
  • Application without consideration of local anatomy
• Recommended maximum safe time: 2 hours in a healthy adult
• If a procedure exceeds 2 hours, it is better to complete it rapidly than to deflate for 10 minutes - because 40 minutes is required for tissues to return to normal after prolonged use; a 10-minute break is inadequate

2. Post-Tourniquet Syndrome (Bunnell)

• Characterized by: edema, pallor, joint stiffness, motor weakness, and subjective numbness
• Caused by prolonged ischemia (not the mechanical effect of the cuff itself)
• Increases narcotic requirements and delays early mobilization
• Spontaneously resolves within 1 week

3. Ischemic Complications

• Compartment syndrome
• Rhabdomyolysis
• Pulmonary embolism - asymptomatic emboli can occur within 1 minute of tourniquet release (number of emboli correlates with duration of inflation)

4. Vascular Complications

• Risk in severe arteriosclerosis or patients with prosthetic vascular grafts
• Never apply a tourniquet over a prosthetic vascular graft

5. Skin Complications

• Chemical burns from skin preparation solutions accumulating under the cuff
• Blisters and skin necrosis from wrinkled padding

Safety Rules (Campbell's Key Concepts)

1. Tourniquet time ≤ 2 hours in a healthy adult
2. Use wider cuff (not higher pressure) for larger extremities
3. Avoid straight tourniquets on conical thighs
4. Prepare and drape the limb before applying the tourniquet to prevent cleansing solution running underneath
5. Ensure pneumatic tourniquets are in good working order before use
6. No rubber ring tourniquets on digits - risk of being forgotten under dressings
7. Administer prophylactic antibiotics within 1 hour of tourniquet inflation
8. Do not apply over a prosthetic vascular graft
9. When blood supply to a limb is questionable (peripheral vascular disease), tourniquet is contraindicated

Antibiotic Timing (Clinical Pearl)

Uses of Tourniquet in Orthopaedics

PART A: Surgical Uses (Intraoperative) - 5 marks

1. To Create a Bloodless Operative Field

2. Hand and Upper Limb Surgery

• Tendon repairs (flexor and extensor tendons)
• Nerve repairs and nerve grafting
• Carpal tunnel decompression
• Dupuytren's contracture release
• Wrist arthroplasty and arthroscopy
• Microvascular surgery (anastomosis of vessels)
• The pneumatic tourniquet on the upper arm is the standard; forearm/wrist tourniquet is used for distal procedures

3. Total Knee Arthroplasty (TKA)

4. Foot and Ankle Surgery

• ORIF of ankle fractures
• Calcaneal fractures
• Forefoot and midfoot procedures (bunion correction, metatarsal osteotomies)
• Ankle arthroplasty and arthroscopy
• Thigh or calf/ankle cuff used depending on the procedure level

5. Arthroscopic Surgery

• Knee arthroscopy (thigh tourniquet)
• Ankle and wrist arthroscopy
• Provides clear visualization in the joint fluid medium

6. Bone Tumour and Soft Tissue Tumour Surgery of Limbs

7. Replantation and Microvascular Surgery

8. Intravenous Regional Anaesthesia (Bier's Block)

• The proximal cuff is inflated first to isolate the limb
• Local anaesthetic (lignocaine) is injected IV into the exsanguinated limb
• Once anaesthesia is established, the distal cuff (over anaesthetized skin) is inflated and the proximal cuff released - reduces tourniquet pain
• Used for manipulation of fractures, minor hand surgery, carpal tunnel release

PART B: Emergency / Trauma Uses + Contraindications (5 marks)

9. Haemorrhage Control in Trauma

• Control of life-threatening limb hemorrhage from open fractures, vascular injuries, traumatic amputations
• Military use has shown tourniquet use reduced limb exsanguination deaths from 9% (Vietnam) to 2% (Iraq/Afghanistan)
• Applied when direct pressure fails to control bleeding
• Safe for up to 6 hours in emergency trauma settings

10. Amputation Surgery

• Used during definitive surgical amputation at all levels (below-knee, above-knee, upper limb amputations)
• Allows clean transection through tissues with minimal blood loss

11. Exsanguination Only (Esmarch Bandage Use)

Contraindications (Important for Exam)

Key Exam Points to Remember

• Maximum safe inflation time: 2 hours (average healthy adult)
• Tourniquet pressure: systolic BP + 50-100 mmHg (or 135-255 mmHg upper limb; 175-305 mmHg lower limb - Campbell's)
• Bier's block requires a double-cuff tourniquet specifically
• Tourniquet is NOT used when blood supply to the limb is questionable
• Never apply over a prosthetic vascular graft
• Antibiotic prophylaxis within 1 hour of inflation

Antibiotic Prophylaxis in Orthopaedics

1. Definition

2. Rationale / Why Prophylaxis is Needed

• Most involve implanted foreign material (screws, plates, nails, prostheses) which bacteria can colonize via biofilm formation
• Bone is relatively avascular and has reduced natural resistance to infection
• SSI in orthopaedics carries catastrophic consequences - implant failure, osteomyelitis, periprosthetic joint infection (PJI), need for revision surgery
• Accepted practice for over 30 years; clearly decreases postoperative infection rates (Campbell's Operative Orthopaedics, 15th Ed.)

3. Wound Classification (CDC / Altemeier Classification)

4. Organisms Most Commonly Causing Orthopaedic SSI

5. Drug of Choice

First-Line: Cefazolin (First-generation Cephalosporin)

• Covers S. aureus and most skin flora effectively
• Excellent bone and soft tissue penetration
• Good safety profile, long half-life, cost-effective
• Dose: 1-2 g IV (2 g if patient weight > 80 kg; 3 g if > 120 kg)
• Provides broad-spectrum coverage against Gram-positives and many Gram-negatives

Alternatives:

6. Timing of Administration

• Standard rule: Antibiotics must be given within 60 minutes before skin incision to ensure adequate tissue and bone drug levels at the time of contamination
• Cefazolin specifically: within 1 hour of tourniquet inflation (Campbell's)
• Vancomycin and fluoroquinolones: given within 60-120 minutes before incision (slower infusion required)
• A prospective randomized study showed administration of antibiotics 1 minute after tourniquet inflation achieved cefazolin concentrations in soft tissue and bone at or above minimum inhibitory concentrations - giving antibiotics before tourniquet inflation did not yield better results
• Late administration (>1 hour before incision) is ineffective - the antibiotic window has passed

7. Intraoperative Redosing

• If estimated blood loss exceeds 1500 mL intraoperatively, an additional dose is given regardless of time
• Prolonged surgical duration is independently associated with increased SSI risk

8. Duration of Postoperative Prophylaxis

• Single preoperative dose is adequate for most clean orthopaedic procedures
• Maximum duration: 24 hours postoperatively for clean-contaminated wounds
• No evidence supports continuing antibiotics until drains, catheters, or lines are removed
• Prolonged use increases antibiotic resistance, C. difficile risk, adverse effects, and cost
• Exception: Open fractures require continued antibiotics beyond 24 hours (see below)

9. Specific Situations in Orthopaedics

A. Total Joint Arthroplasty (Hip / Knee)

• Cefazolin 2 g IV within 60 minutes of incision
• Redose every 3-4 hours if procedure prolonged
• Continue for 24 hours postoperatively (some centres: single dose only)
• Preoperative nasal screening for S. aureus with decolonization using mupirocin ointment (nasal) + chlorhexidine baths recommended as adjunct - significantly reduces deep SSI rates
• MRSA-positive patients: switch prophylaxis to Vancomycin

B. Open Fractures (Gustilo-Anderson Classification)

• Antibiotics must be started as early as possible (ideally in Emergency Department) - the "golden period" principle
• Tetanus prophylaxis administered alongside

C. Spinal Surgery with Instrumentation

• Cefazolin standard
• Vancomycin powder applied locally to wound (intrawound) is increasingly used in addition to IV prophylaxis - reduces SSI in high-risk spinal cases
• Some centres use Vancomycin IV for instrumented fusions, especially posterior spine

D. Closed Fractures / Routine Elective Orthopaedic Procedures (without implant)

• Cefazolin single dose preoperatively
• Some debate on need at all for simple procedures (e.g., diagnostic arthroscopy)

E. Hand Surgery

• Cefazolin for clean hand procedures with implants (ORIF, arthroplasty)
• For bites or contaminated hand wounds: amoxicillin-clavulanate or co-amoxiclav to cover polymicrobial flora including anaerobes

10. Contraindications to Standard Prophylaxis

1. Known allergy to cephalosporins or penicillins (modify regimen as above)
2. Pre-existing infection - switch to therapeutic antibiotics (culture-directed)
3. Renal impairment - adjust doses of renally-cleared agents (e.g., vancomycin, gentamicin)
4. MRSA colonization - use vancomycin prophylaxis

11. Additional Measures to Reduce SSI (Adjuncts to Antibiotic Prophylaxis)

1. Preoperative skin preparation - chlorhexidine-alcohol > povidone-iodine for skin decolonization
2. Povidone-iodine irrigation of wound before closure - reduces PJI in arthroplasty (dilute 0.35%)
3. Antibiotic-loaded bone cement (ALBC) - gentamicin or tobramycin cement in total joint arthroplasty; especially for revision cases
4. Antibiotic bead pouches (PMMA beads with antibiotics) - local delivery; more effective than NPWT in reducing bacterial counts in contaminated wounds
5. Nasal decolonization with mupirocin for S. aureus carriers before elective arthroplasty
6. Normothermia maintenance intraoperatively - hypothermia impairs immune function
7. Blood glucose control - hyperglycemia increases SSI risk significantly
8. VTE prophylaxis - concurrent important perioperative measure
9. Wound drains removed early; no antibiotic cover needed until drain removal

12. Summary Table

Antiseptic Agents for Skin Preparation in Orthopaedics

1. Introduction / Definition

2. Need for Skin Preparation in Orthopaedics

• Most involve metallic implants (nails, screws, plates, prostheses) - foreign material dramatically amplifies infection risk
• Bone and joint infections are catastrophic - osteomyelitis, periprosthetic joint infection, implant failure
• Skin harbours both transient flora (easily removed) and resident flora (deeper, harder to eliminate)
• SSIs increase mortality, hospital stay, and cost

3. Classification of Antiseptic Agents

A. Alcohols

B. Iodine and Iodophors

C. Chlorhexidine

D. Hexachlorophene

E. Miscellaneous (hydrogen peroxide, acridines, quaternary ammonium compounds)

4. Individual Agents - Detailed Description

A. ALCOHOLS (Ethyl Alcohol / Isopropyl Alcohol)

• Ethyl alcohol (ethanol): 70-95%
• Isopropyl alcohol: 70%
• 95% ethanol is superior to 70-75% (dilution by moist skin reduces efficacy of lower concentrations)

• Denatures and precipitates bacterial proteins
• Disrupts lipid cell membranes
• Coagulates intracellular proteins
• Rapid action within seconds

• Bactericidal (Gram-positive and Gram-negative)
• Fungicidal
• Virucidal (enveloped viruses)
• NOT sporicidal

• Excellent immediate bactericidal action - fastest onset of all antiseptics
• Inexpensive, widely available
• No residue left on skin

• Short duration of action - dries quickly, no persistent or residual effect
• Not sporicidal
• Flammable - fire risk with diathermy/electrocautery; must be fully dried before use
• Skin irritation with repeated use
• Not effective against spores or some non-enveloped viruses
• Must dry completely before draping to avoid pooling and chemical burns

• Almost always used in combination with another antiseptic (chlorhexidine or povidone-iodine) rather than alone
• Rapid pre-injection skin wipe in minor procedures

B. IODINE AND IODOPHORS

i. Iodine (Aqueous and Tincture)

• Tincture of iodine = iodine in alcohol (2% iodine in 70% alcohol) - alcoholic
• Lugol's solution = aqueous iodine (5% iodine + 10% KI in water)

• Free iodine penetrates the cell wall and oxidises key cellular constituents including proteins, nucleic acids, and membrane lipids - results in cell death

• Broad: bactericidal, fungicidal, virucidal, protozoal, sporicidal
• Effective against both Gram-positive and Gram-negative organisms

• Frequent skin irritation (tincture - can be lessened by adding iodine to alcohol)
• True allergic reactions (Lugol's)
• Stains skin and linen
• Inactivated by organic matter (blood, pus) - must clean skin first
• Toxic to open wounds and mucous membranes

ii. Iodophors - Povidone-Iodine (PVP-I / Betadine)

• Iodine complexed with polyvinyl pyrrolidone (PVP) or povidone as carrier
• Available as: 10% solution (= 1% available iodine), 7.5% scrub solution, paint solution

• The povidone acts as a slow-release reservoir of free iodine
• Slower but sustained release of iodine compared to plain iodine
• Same oxidative mechanism as iodine

• Broad: bactericidal (Gram-positive and Gram-negative), fungicidal, virucidal, sporicidal

• Slower, sustained release of iodine - more prolonged action
• Fewer skin reactions than plain iodine
• Less staining
• Lower tissue toxicity
• Covers both Gram-negative and Gram-positive organisms

• Inactivated by organic material (blood, serum, pus) - less effective in contaminated wounds
• May be absorbed systemically through large raw areas (iodine toxicity)
• Contraindicated in thyroid disease (may precipitate thyroid dysfunction)
• Contraindicated in neonates and premature infants (systemic absorption through immature skin)
• Can damage open cartilage surfaces (intra-articular use controversial)
• Allergic reactions possible (true iodine allergy)
• Inferior to chlorhexidine-alcohol for SSI prevention in multiple comparative studies

• Dilute povidone-iodine irrigation (0.35%) of surgical wounds before closure in total joint arthroplasty - shown to significantly reduce periprosthetic joint infection (PJI) rates (Shohat et al., J Arthroplasty 2022 - 31,331 cases)
• Routine skin preparation before incision
• Wound packing/dressings in infected orthopaedic wounds

C. CHLORHEXIDINE GLUCONATE

• 4% aqueous (Hibiscrub) - scrub
• 0.5% in 70% isopropyl alcohol (Hydrex, Chloraprep) - paint
• 2% chlorhexidine + 70% isopropyl alcohol - currently most recommended preparation

• Binds to negatively charged bacterial cell membrane
• Disrupts cell membrane integrity causing leakage of cytoplasmic contents
• At high concentrations: causes coagulation of cytoplasm
• Persistent activity due to binding to stratum corneum proteins

• Bactericidal - Gram-positive > Gram-negative
• Fungistatic
• Some virucidal activity
• NOT sporicidal
• Less effective against Gram-negative organisms than iodine

• Binds to skin proteins and remains active for hours after application (up to 6 hours)
• Repeated washings have a cumulative bactericidal effect - builds up over days of preoperative preparation
• This residual action is chlorhexidine's major advantage over iodine and alcohol

• Best combination of immediate and persistent (residual) antimicrobial activity
• Cumulative effect with repeated use
• Less affected by blood and organic matter than iodine
• Better patient tolerance; less skin irritation
• Current gold standard - multiple studies show superiority over povidone-iodine for SSI prevention
• WHO recommends chlorhexidine-alcohol as first choice for surgical antisepsis (Bailey & Love, 28th Ed.)
• NICE guidelines (2008) confirm: 2% chlorhexidine + 70% isopropyl alcohol is best at preventing SSI
• Sabiston (2024): "It is now standard that chlorhexidine + alcohol preparation be used for surgical site antisepsis unless contraindicated"

• Ototoxic - must not enter the middle ear (contraindicated for head/ear surgery near tympanic membrane)
• Corneal damage - avoid eye contact
• Contraindicated on mucous membranes and open wounds/raw areas
• Not for use on brain or meninges
• Possible anaphylactic reactions (rare but reported; type I hypersensitivity)
• Relatively more expensive than povidone-iodine

• Routine preoperative skin preparation - limb, spine, pelvis surgery
• Preoperative whole-body wash (1-2 days before elective arthroplasty) for S. aureus decolonisation
• Combined with nasal mupirocin for MRSA decolonisation protocol before total joint arthroplasty

D. HEXACHLOROPHENE (pHisoHex)

• 3% hexachlorophene detergent preparation

• Disrupts bacterial cell membrane
• Bacteriostatic at low concentrations; bactericidal at higher concentrations
• Forms a persistent film on skin with retained bacteriostatic properties

• Strong effect against Gram-positive cocci (especially S. aureus, S. pyogenes)
• Little activity against Gram-negative organisms
• Not effective against spores, fungi, or viruses

• Forms a persistent film on skin - prolonged action
• Good anti-staphylococcal activity

• Easily washed off
• Requires multiple applications to be maximally effective
• Neurotoxic in neonates and infants - systemic absorption causes vacuolar encephalopathy
• Must NOT be used on infants, neonates, or large body surface areas
• Poor Gram-negative coverage makes it inadequate as sole agent

E. HYDROGEN PEROXIDE (H₂O₂)

• 3% solution used for wound cleansing
• Mechanism: releases nascent oxygen on contact with tissue catalase - effervescence disrupts biofilm and mechanically loosens debris
• Bactericidal, virucidal, sporicidal (at higher concentrations)
• Not suitable for routine skin prep (tissue-damaging, inhibits wound healing)
• Used for wound irrigation, especially in infected orthopaedic wounds and osteomyelitis debridement

5. Comparative Summary Table

6. Current Recommended Protocol for Orthopaedic Skin Preparation

A. Preoperative (Day before surgery - for elective arthroplasty)

• Whole-body shower or bath with 4% chlorhexidine soap the evening before and morning of surgery
• Decolonises resident skin flora, especially S. aureus

B. Hair removal

• Electric clippers preferred - razor blades increase infection risk (micro-abrasions)
• Hair removed only if it interferes with the surgical site - not routinely

C. Operative skin preparation - Technique

1. Apply 2% chlorhexidine gluconate in 70% isopropyl alcohol (ChloraPrep) - the current gold standard combination
2. Apply using concentric circles starting from the incision site and moving outward (clean to dirty in clean wounds; for contaminated wounds - start periphery and move inward)
3. Allow to dry completely (minimum 3 minutes for alcohol-based solutions) - prevents chemical burns and fire hazard with diathermy
4. Cover tourniquet site with circumferential adhesive drape to prevent antiseptic run-under and chemical burn
5. Apply sterile drapes only after solution is fully dry

D. Special circumstances

7. Ideal Properties of a Skin Antiseptic

1. Broad antimicrobial spectrum
2. Rapid onset of action
3. Prolonged residual / persistent activity
4. Not inactivated by organic matter (blood, pus, proteins)
5. Safe for skin, non-irritant, non-allergenic
6. Non-toxic to tissues, cells, and deeper structures
7. Stable on storage; long shelf life
8. Economical and widely available
9. No systemic absorption / toxicity
10. Should not interfere with wound healing

8. Key Exam Points

• Gold standard: 2% chlorhexidine + 70% isopropyl alcohol
• Residual activity: Chlorhexidine > Iodophors > Alcohol (none)
• Sporicidal: Only iodine/iodophors
• Ototoxic: Chlorhexidine
• Neurotoxic in neonates: Hexachlorophene
• Inactivated by organic matter: Iodine/Iodophors
• Fire hazard: Alcohols - must dry completely before diathermy
• Wound irrigation (PJI prevention): Dilute povidone-iodine 0.35%
• Never apply antiseptic under tourniquet - causes chemical burns