What precautions should be taken in older adults with cardiovascular disease and possibly osteoporosis, taking diuretics and warfarin, who are at high risk of bone cement implantation syndrome (BCIS)?

Why Diuretics and Warfarin Increase BCIS Risk

Diuretic use is an independent predictor of severe bone cement implantation syndrome (BCIS) because it predisposes patients to intravascular volume depletion, which critically impairs their ability to compensate for the sudden hemodynamic insult caused by cement insertion. 1, 2

The Mechanism Behind Diuretic-Associated Risk

Diuretics create a state of relative hypovolemia that becomes catastrophic during cemented arthroplasty. When bone cement is inserted, multiple mechanisms trigger cardiovascular collapse:

• Fat, platelet, fibrin, and marrow emboli are forced into the venous circulation during femoral canal instrumentation 1
• Vasoactive mediators are released systemically, causing profound vasodilation 1
• Right heart strain occurs from pulmonary embolization, evidenced by sudden drops in end-tidal CO2 3

In diuretic-treated patients, the depleted intravascular volume leaves no hemodynamic reserve to buffer these insults, resulting in precipitous blood pressure drops exceeding 40% of baseline (Grade 2 BCIS) or complete cardiovascular collapse requiring CPR (Grade 3 BCIS). 1, 2

Why Warfarin Compounds the Risk

Warfarin independently predicts severe BCIS, though the mechanism differs from diuretics. 2 Warfarin-anticoagulated patients likely experience:

• Enhanced bleeding into the femoral canal during instrumentation, increasing the volume of embolic material 2
• Greater marrow content embolization due to impaired local hemostasis 2
• Potential for paradoxical embolization in patients with patent foramen ovale 4

The Synergistic Danger

When combined, these medications create a "perfect storm":

• Hypovolemia from diuretics eliminates compensatory mechanisms 1
• Anticoagulation from warfarin maximizes embolic load 2
• Underlying cardiovascular disease (the reason for both medications) further limits physiologic reserve 1

The data confirms this danger: severe BCIS (Grades 2-3) carries 35% mortality for Grade 2 and 88% mortality for Grade 3, compared to 5-9% for lesser grades. 2

Critical Risk Stratification

Patients on diuretics and warfarin typically have multiple compounding risk factors:

• Advanced age (often >75 years) 1, 5
• Male sex 1, 6
• Significant cardiopulmonary disease (heart failure, COPD) 1, 2
• ASA Class III-IV status 2, 5
• Renal impairment (common with chronic diuretic use) 5

These patients face a 16-fold increase in mortality when severe BCIS occurs. 2

Mandatory Precautions for High-Risk Patients

Preoperative Optimization

• Ensure aggressive hydration before induction and throughout surgery to counteract diuretic-induced volume depletion 1, 6
• Consider invasive blood pressure monitoring (arterial line) for all high-risk patients 1, 6
• Have vasopressors drawn and immediately available (metaraminol/epinephrine) before cement application 1, 3

Surgical Technique Modifications

• Use pressurized lavage system to thoroughly clean the femoral canal of fat and marrow 1, 6, 7
• Insert cement retrograde with cement gun on top of intramedullary plug 1, 6, 7
• Place distal suction catheter and remove immediately when blocked with cement 1, 6
• Avoid excessive manual pressurization or pressurization devices in these high-risk patients 1, 6, 7

Anesthetic Management

• Maintain systolic blood pressure within 20% of pre-induction values using vasopressors and fluids 1, 3
• Increase FiO2 to 100% at time of cementation 1, 3
• Establish mandatory verbal communication: surgeon announces intent to cement, anesthesiologist confirms awareness 1, 3
• Monitor for sudden end-tidal CO2 drops indicating right heart failure 3

Common Pitfalls to Avoid

The most dangerous error is assuming adequate hydration status based on appearance alone. Chronic diuretic users are chronically volume-depleted despite appearing euvolemic. 1

Delayed recognition of BCIS is lethal. Grade 1 BCIS (oxygen saturation <94% or >20% systolic BP drop) occurs in ~20% of cases and can rapidly progress to Grade 3 without immediate intervention. 6, 3

Failure to have vasopressors immediately available results in critical delays during cardiovascular collapse. Draw up metaraminol or epinephrine before cement insertion, not after hypotension develops. 1, 3

Alternative Consideration

For patients with multiple BCIS risk factors including diuretics and warfarin, multidisciplinary discussion should address whether uncemented arthroplasty is safer, though this must be weighed against increased periprosthetic fracture risk in osteoporotic bone. 8, 5 However, cemented prostheses remain the standard for hip fracture surgery due to superior pain-free mobility and reduced reoperation rates. 6, 7