What are the risks of delaying surgery for hip fractures?

Risks of Delaying Surgery for Hip Fractures

Yes, delaying hip fracture surgery beyond 48 hours significantly increases mortality, complications, and hospital length of stay, and the most recent evidence suggests that delays beyond even 12 hours may increase 30-day mortality risk. 1

Critical Time Thresholds

The target for hip fracture surgery should be within 36 hours in the UK and within 48 hours internationally. 1, 2 However, the most recent data from 2025 indicates that surgical delays beyond 12 hours significantly increase the adjusted risk of 30-day mortality in patients over 50 years of age. 1 This represents an important evolution from prior 48-hour thresholds and suggests earlier intervention may be beneficial.

Specific Risks of Surgical Delay

Mortality Risk

• Delays beyond 48 hours are associated with increased mortality, with the effect becoming more pronounced as delay extends. 1
• Delays beyond 12 hours significantly increase 30-day mortality risk according to the most recent 2025 evidence. 1
• Research shows that delays beyond 4 days result in significantly increased mortality at 90 days (hazard ratio 2.25) and one year (hazard ratio 2.4). 3

Morbidity and Complications

Delaying surgery beyond 48 hours increases the following complications: 1

• Pressure sores from prolonged immobilization
• Pneumonia from bed rest and reduced respiratory function
• Thromboembolic complications including deep vein thrombosis and pulmonary embolism
• Urinary tract infections from catheterization and immobility

Healthcare System Impact

• Prolonged hospital length of stay 1
• Increased healthcare costs 1
• Higher complication rates overall 1

When Delay is Acceptable vs. Unacceptable

Acceptable Reasons for Delay 1

The following medical conditions justify brief surgical delay for optimization:

• Hemoglobin concentration < 8 g/dL (< 80 g/L)
• Severe electrolyte abnormalities: sodium < 120 or > 150 mmol/L, potassium < 2.8 or > 6.0 mmol/L
• Uncontrolled diabetes
• Uncontrolled or acute onset left ventricular failure
• Correctable cardiac arrhythmia with ventricular rate > 120/min
• Chest infection with sepsis
• Reversible coagulopathy

Unacceptable Reasons for Delay 1

The following should NEVER justify surgical delay:

• Lack of facilities or theatre space
• Awaiting echocardiography (proceed with invasive monitoring instead)
• Unavailable surgical expertise (this represents a systems failure)
• Minor electrolyte abnormalities

Critical Evidence Nuance

There is no evidence that delaying surgery to allow pre-operative physiological stabilization improves outcomes. 1 This is a crucial point: the traditional practice of "optimizing" patients before surgery does not improve mortality or morbidity when it results in delays beyond 36-48 hours. The 36-hour window provides sufficient time for proactive medical optimization without incurring the risks of prolonged delay. 1

The 2020 HIP ATTACK trial found that accelerated surgery (within 6 hours) did not improve mortality or major complications compared to standard care (median 24 hours), but it did significantly reduce postoperative delirium (9% vs 12%), length of stay, and improved mobilization speed. 1 This suggests that while ultra-early surgery may not reduce mortality, it provides meaningful quality-of-life benefits without causing harm.

Common Pitfalls to Avoid

Do not cancel surgery on the day of operation for minor abnormalities. 1 Instead, anaesthetists should be proactively involved within the 36-hour window to correct medical obstacles. If cancellation is unavoidable, patients require 12-hourly reassessment by anaesthetic teams with clear documentation of optimization plans. 1

Do not delay surgery for echocardiography in patients with suspected valvular heart disease. 1 Delay for echocardiography increases postoperative mortality, and the results rarely change anaesthetic management. Instead, proceed with carefully monitored general or spinal anaesthesia maintaining coronary and cerebral perfusion pressures. 1

The Association of Anaesthetists states that "surgery is the best analgesic for hip fractures," 2 emphasizing that prolonged immobilization with pain contributes significantly to poor outcomes and that expedited surgery is itself a therapeutic intervention.