What are the risks of a 96-year-old female with a history of severe aortic stenosis (AS) undergoing hip surgery?

Risks of Hip Surgery in a 96-Year-Old Female with Severe Aortic Stenosis

A 96-year-old female with severe aortic stenosis undergoing hip surgery faces significantly elevated perioperative mortality and morbidity risks, with mortality rates potentially exceeding 10%. 1

Cardiovascular Risks

Hemodynamic Complications

• Hypotension: Patients with severe AS cannot tolerate hypotension, which can lead to decreased coronary perfusion pressure and myocardial ischemia 1
• Tachycardia: Rapid heart rates reduce diastolic filling time, compromising cardiac output 1
• Fluid management challenges: Both volume depletion and overload are poorly tolerated 1

Specific Cardiac Complications

• Myocardial infarction: 3-5.7% risk compared to 1.1-2.7% in patients without AS 1
• Heart failure: Acute decompensation due to perioperative stress 1
• Arrhythmias: Particularly atrial fibrillation, which can cause clinical deterioration 1
• Composite adverse cardiac outcomes: 4.4-5.7% (compared to 1.7-2.7% in patients without AS) 1

Surgical Risk Factors

Hip surgery in this patient represents high-risk surgery due to:

• Advanced age (96 years)
• Potential for large fluid shifts and blood loss
• Prolonged surgical time
• Risk of cement implantation syndrome if cemented prosthesis is used 1

Risk Stratification

The European Society of Cardiology guidelines identify several factors that increase perioperative risk in patients with severe AS undergoing non-cardiac surgery 1:

1. Symptomatic status: Symptomatic severe AS carries higher risk (OR: 2.7)
2. Coexisting valvular disease: Particularly mitral regurgitation (OR: 9.8)
3. Pre-existing coronary artery disease: Increases risk (OR: 2.7)
4. High-risk surgery: Hip surgery falls into this category (OR: 7.3)

Management Considerations

Preoperative Assessment

• Echocardiography is mandatory to assess AS severity, ventricular function, and pulmonary pressures 1
• Evaluation for concurrent coronary artery disease is warranted 1

Perioperative Management

• Invasive hemodynamic monitoring is essential, including arterial line and possibly pulmonary artery catheter 1
• Careful anesthetic approach specific to AS physiology:
  • Maintain preload
  • Avoid tachycardia
  • Maintain systemic vascular resistance
  • Avoid myocardial depression 1
• Postoperative ICU admission is prudent even if the patient appears stable 1

Alternative Approaches to Consider

For patients with severe symptomatic AS facing high-risk non-cardiac surgery, guidelines suggest considering:

1. Transcatheter aortic valve replacement (TAVR) before non-cardiac surgery in patients at prohibitive surgical risk for conventional AVR 1
2. Balloon aortic valvuloplasty as a bridge to surgery in hemodynamically unstable patients 1

Common Pitfalls to Avoid

1. Underestimating risk: Age alone should not be the determining factor for surgical decisions, but the combination of advanced age and severe AS significantly increases risk 2

2. Inadequate monitoring: Failure to implement appropriate invasive monitoring can lead to missed opportunities for early intervention 1

3. Poor communication: Lack of coordination between surgical, anesthesia, and cardiology teams increases risk 1

4. Inappropriate fluid management: Both hypovolemia and hypervolemia can precipitate hemodynamic collapse 1

The decision to proceed with hip surgery in this patient requires careful weighing of the benefits against the substantial risks, with full involvement of a multidisciplinary team including cardiology, anesthesiology, and orthopedic surgery.