What are the anesthesia recommendations for a 55-year-old male with a history of coronary artery disease (CAD) with stents undergoing cystoscopy due to hydronephrosis caused by kidney stones?

Anesthesia Recommendations for a 55-Year-Old Male with CAD and Stents Undergoing Cystoscopy for Hydronephrosis

For this patient with coronary artery disease and stents undergoing cystoscopy for hydronephrosis, monitored anesthesia care with careful hemodynamic monitoring is strongly recommended to minimize cardiovascular risk.

Preoperative Assessment

• Cardiac Status Evaluation:

  • Assess current stent status (type and time since placement)
  • Determine if patient is on dual antiplatelet therapy
  • Review most recent cardiac function tests (ECG, echocardiogram)
  • Evaluate for symptoms of angina or heart failure

• Renal Function Assessment:

  • Check baseline creatinine and eGFR
  • Assess hydration status
  • Review electrolytes, especially potassium

Anesthetic Approach

Recommended Technique

• Monitored Anesthesia Care (MAC) with local anesthesia is preferred for this low-risk procedure 1
• If general anesthesia is required, use a balanced technique with careful titration of agents

Hemodynamic Goals

• Maintain hemodynamic stability with particular attention to:
  • Avoid tachycardia (maintain heart rate <80 bpm)
  • Maintain systolic blood pressure within 20% of baseline
  • Avoid hypotension which may decrease coronary perfusion pressure 1

Medication Considerations

• Anesthetic Agents:

  • Use lidocaine or mepivacaine for local anesthesia
  • If sedation needed: titrated midazolam and fentanyl
  • If general anesthesia required: etomidate or reduced-dose propofol for induction

• Antiplatelet Management:

  • Continue aspirin perioperatively
  • Consult with cardiologist regarding management of P2Y12 inhibitors (clopidogrel, ticagrelor)
  • If stent placement was recent (<6 months for DES, <1 month for BMS), consider postponing elective procedure

Intraoperative Management

• Monitoring:

  • Standard ASA monitors plus:
  • Continuous arterial blood pressure monitoring if patient has unstable CAD
  • Consider intraoperative TEE if patient has significant cardiac dysfunction 1

• Fluid Management:

  • Use isotonic crystalloids (normal saline or lactated Ringer's)
  • Avoid fluid overload that could exacerbate hydronephrosis
  • Target euvolemia with careful titration

• Contrast Media Considerations:

  • If contrast will be used during cystoscopy:
    • Use iso-osmolar contrast agents 1
    • Minimize contrast volume
    • Consider pre-procedure hydration with isotonic saline (1 mL/kg/hr for 12 hours) 2
    • Hold metformin for 48 hours after contrast administration if patient is taking it 2

Postoperative Care

• Monitoring Period:

  • Continue hemodynamic monitoring for 1-2 hours post-procedure
  • Monitor for cardiac symptoms (chest pain, dyspnea, arrhythmias)
  • Check ECG if any concerning symptoms develop

• Pain Management:

  • Use multimodal analgesia with acetaminophen and low-dose opioids as needed
  • Avoid NSAIDs due to potential renal effects in a patient with hydronephrosis

• Fluid Management:

  • Continue IV fluids until adequate oral intake is established
  • Monitor urine output to ensure resolution of obstruction
  • Check post-procedure creatinine if contrast was used

Potential Complications and Management

• Cardiac Events:

  • Have vasopressors readily available (phenylephrine preferred in patients with CAD) 1
  • For hypertension, use short-acting calcium channel blockers rather than nitrates 1
  • For bradycardia, have atropine immediately available

• Urologic Complications:

  • Monitor for signs of urinary tract infection post-procedure
  • Ensure adequate drainage of hydronephrosis was achieved

Key Pitfalls to Avoid

1. Neglecting antiplatelet management - Inappropriate discontinuation of antiplatelet therapy can lead to stent thrombosis
2. Inadequate hemodynamic monitoring - Failure to detect and promptly treat hemodynamic instability
3. Overlooking renal function - Not accounting for potential worsening of renal function with contrast use
4. Fluid mismanagement - Either excessive or insufficient fluid administration can worsen cardiac and renal outcomes

By following these recommendations, the anesthesiologist can minimize cardiovascular risk while providing appropriate anesthesia care for this patient's cystoscopy procedure.