Bone cement implantation syndrome

Surgical approach (where BCIS occurs)

• Most commonly during cemented hip hemiarthroplasty for fractured neck of femur; also cemented THR/TKR, revision arthroplasty, vertebroplasty/kyphoplasty
• Key surgical steps associated with BCIS risk
  • Femoral canal preparation: reaming/broaching, lavage, drying
  • Cement mixing and insertion (often with pressurisation) into femoral canal
  • Insertion of femoral stem/prosthesis (highest-risk moment), reduction of joint
  • Tourniquet release can be relevant in cemented knee arthroplasty
• Risk-reduction surgical techniques (agree pre-op)
  • High-pressure pulsatile lavage to reduce intramedullary fat/marrow load
  • Drying canal; retrograde cement gun insertion; avoid excessive pressurisation where possible
  • Venting (femoral vent hole) in selected high-risk cases to reduce intramedullary pressure
  • Communicate before cementation/stem insertion so anaesthetist can optimise and increase vigilance

Anaesthetic management (typical for cemented hip hemiarthroplasty)

• Type of anaesthesia: GA or spinal (both acceptable; choice depends on patient physiology, anticoagulation, urgency, and ability to manage sudden collapse)
  • GA: allows controlled ventilation, rapid FiO2 increase, easier airway control during collapse
  • Spinal: common in NOF; ensure ability to manage hypotension and conversion to GA if needed
• Airway: ETT preferred in high-risk patients (severe cardiorespiratory disease) or if high likelihood of deterioration; SGA may be acceptable in low-risk, stable patients
• Duration: typically 1–2 hours (hemiarthroplasty often ~60–90 min; longer if complex)
• How painful: moderate–severe; plan multimodal analgesia
  • Options: paracetamol ± NSAID (if appropriate), opioid titration, fascia iliaca block/PNB, local infiltration by surgeon
• Monitoring: minimum ASA; consider arterial line in high-risk or cemented cases with significant comorbidity; capnography essential (GA) and helpful even under sedation
  • Have vasopressors drawn up before cementation (metaraminol/phenylephrine; consider noradrenaline infusion in frail/high-risk)

Definition and clinical importance

• BCIS: a constellation of hypoxia, hypotension, pulmonary hypertension, arrhythmias, loss of consciousness and/or cardiac arrest occurring around cementation, prosthesis insertion, or joint reduction (classically in cemented hip surgery)
• High morbidity/mortality risk in frail NOF population; requires proactive prevention and rapid treatment

Timing (when to expect it)

• Most often at femoral canal cementation and especially stem insertion/pressurisation
• Also during joint reduction, tourniquet release (cemented knee), or manipulation increasing intramedullary pressure

Pathophysiology (what causes the collapse)

• Central concept: embolisation + pulmonary vascular response → acute rise in PVR → RV strain/failure → reduced LV preload → hypotension/collapse
  • Embolic load: fat, marrow, air, cement particles, platelet/fibrin aggregates
  • Pulmonary vasoconstriction mediated by vasoactive substances (e.g., thromboxane, complement activation) and hypoxia/hypercarbia
• Additional contributors
  • Reduced venous return from hypotension/anaesthetic depth/positioning
  • Myocardial ischaemia/arrhythmias due to acute RV pressure overload and hypoxia
  • MMA monomer toxicity is not considered the primary mechanism (historical theory)

Risk factors

• Patient factors (high-risk phenotype: frail NOF with limited cardiopulmonary reserve)
  • Older age, ASA III–IV, significant cardiac disease (IHD, valvular disease, cardiomyopathy), pulmonary hypertension, RV dysfunction
  • COPD, hypoxia, limited physiological reserve, anaemia, dehydration/hypovolaemia
  • Pathological fractures, metastatic disease (high embolic burden)
• Surgical/procedural factors
  • Cemented femoral components (vs uncemented), long-stem prostheses, revision surgery
  • High intramedullary pressure: vigorous pressurisation, poor venting, inadequate lavage

Clinical features and diagnosis

• Key signs (often sudden, temporally related to cement/stem)
  • Hypotension (may be profound), hypoxia, fall in ETCO2 (GA), arrhythmias, bronchospasm, altered consciousness (regional), cardiac arrest
  • May see increased CVP, signs of acute RV failure; in severe cases PEA/asystole
• Differential diagnosis (must consider rapidly)
  • Massive PE (thrombus/fat), anaphylaxis, haemorrhage, myocardial infarction, arrhythmia, high spinal/LA toxicity (if regional), tension pneumothorax (rare in this context)

Severity grading (Donaldson classification)

• Grade 1: moderate hypoxia (SpO2 < 94%) or hypotension (SBP drop > 20%)
• Grade 2: severe hypoxia (SpO2 < 88%) or hypotension (SBP drop > 40%) or unexpected loss of consciousness
• Grade 3: cardiovascular collapse requiring CPR

Prevention (anaesthetic + team measures)

• Pre-op planning and communication
  • Identify high-risk patients; discuss cemented vs uncemented option with surgeon where appropriate
  • Agree a clear warning before cement insertion and stem insertion
• Optimise physiology before cementation/stem insertion
  • Correct hypovolaemia; maintain adequate Hb/oxygen delivery; avoid excessive anaesthetic depth at critical moments
  • Increase FiO2 before cementation (often to 1.0 in high-risk) and ensure adequate ventilation (avoid hypercarbia/acidosis which increase PVR)
  • Have vasopressor strategy ready (boluses and/or infusion); consider arterial line
• Intra-op monitoring and vigilance at high-risk moments
  • Watch for sudden fall in ETCO2, SpO2, BP; treat early rather than waiting for full syndrome
• Surgical risk reduction (coordinate with surgeon)
  • Lavage/venting/retrograde cement gun; minimise pressurisation where feasible

Immediate management (structured response)

• Call for help; inform surgeon; stop/hold cementation/pressurisation if possible; ensure 100% oxygen
• Airway/breathing
  • Increase FiO2 to 1.0; confirm airway/ventilation; treat bronchospasm if present
  • GA: check capnography; sudden ETCO2 drop supports embolic event/low CO
• Circulation: treat as acute RV failure with reduced LV preload
  • Vasopressors: metaraminol/phenylephrine boluses for immediate BP support; early noradrenaline infusion in persistent hypotension
  • Consider adrenaline if severe shock/bronchospasm or impending arrest (inotropy + vasoconstriction)
  • Judicious fluids to support RV preload (avoid overload if RV failing and pulmonary pressures high)
  • Treat arrhythmias; aim sinus rhythm; correct hypoxia, acidosis, electrolytes
• If collapse/Grade 3: start ALS; likely PEA—prioritise high-quality CPR, adrenaline, treat reversible causes; consider echo if available to confirm RV dilation
• Post-event: ICU/HDU for monitoring; ABG, lactate; consider troponin/ECG; document and debrief

Postoperative considerations

• Higher risk of postoperative hypoxia, delirium, myocardial injury, AKI after BCIS episode—plan enhanced monitoring and early senior review
• Analgesia: continue multimodal; avoid excessive opioids in frail/hypoxic patients; consider regional techniques