What are the anesthetic considerations and preparations for an 83‑year‑old patient undergoing intramedullary femoral nailing?

Anesthetic Considerations for Femoral Nailing in an 83-Year-Old Patient

For an 83-year-old undergoing femoral nailing, prioritize spinal anesthesia with low-dose bupivacaine (7.5-10 mg) plus intrathecal fentanyl (20-25 mcg), combined with a femoral nerve block for postoperative analgesia, while maintaining strict hemodynamic stability and avoiding sedatives that cause delirium. 1, 2

Pre-operative Assessment and Risk Stratification

Critical Risk Factors to Identify

• Assess for cardiovascular disease, chronic diuretic use, and baseline functional status, as these predict severe intraoperative cardiovascular events and 30-day mortality 3
• Document cognitive baseline and frailty status using comprehensive geriatric assessment, which predicts postoperative delirium and functional decline better than traditional risk scores 4
• Check anticoagulation status: INR must be <1.5 for safe neuraxial anesthesia 1

Physiologic Considerations

• Recognize that elderly patients have reduced physiologic reserve with altered cardiovascular responses to stress, making hemodynamic instability more likely 5, 6
• Expect 20-25% dose reduction per decade after age 55 for all anesthetic agents due to pharmacokinetic and pharmacodynamic changes 7, 6

Anesthetic Technique Selection

Primary Recommendation: Spinal Anesthesia

Administer 7.5-10 mg of 0.5% hyperbaric bupivacaine with 20-25 mcg intrathecal fentanyl 2

• Use the lower dose (7.5 mg) if cardiovascular disease is present to minimize hypotension risk 2
• Intrathecal fentanyl provides 2-5 hours of postoperative analgesia without respiratory or cognitive depression seen with morphine 1
• Doses <10 mg bupivacaine reduce hypotension in elderly patients while maintaining adequate surgical anesthesia 1

Adjunctive Regional Anesthesia

Add a femoral nerve or fascia iliaca block before or after spinal placement 1, 7

• These blocks are amenable to ultrasound guidance and reduce deep hematoma risk in anticoagulated patients 1
• Peripheral nerve blockade reduces opioid requirements and postoperative confusion risk 7, 2

General Anesthesia Considerations (If Spinal Contraindicated)

• Carefully titrate propofol or ketamine induction doses and await response with patience to avoid circulatory collapse 6
• Ketamine maintains cardiovascular stability better than propofol but carries higher postoperative confusion risk in elderly patients 1
• Avoid benzodiazepines entirely as they are strongly associated with postoperative delirium in patients over 60 years 1, 7

Critical Intraoperative Management

Hemodynamic Monitoring and Stability

Establish invasive arterial blood pressure monitoring before induction given the patient's age and cardiovascular risk 3, 2

• Maintain systolic blood pressure within 20% of pre-induction values throughout surgery using vasopressors preferentially over fluids 3
• Have phenylephrine (100-200 mcg boluses) or metaraminol immediately available and administer before giving additional IV fluids to avoid overload 3, 2
• Maintain mean arterial pressure >65 mmHg, as hypotension is associated with increased mortality in elderly patients 2

Fluid Management

Ensure adequate hydration before induction and during anesthesia to prevent hypotension 3

• Avoid excessive IV fluid administration in response to spinal-induced hypotension; use vasopressors first 2

Monitoring Requirements

Continuous pulse oximetry, ECG, and non-invasive blood pressure every 3-5 minutes are mandatory 2

• Provide supplemental oxygen throughout the procedure, particularly given age-related respiratory changes 7, 2

Vigilance for Femoral Canal Instrumentation

Maintain heightened awareness during reaming and nail insertion as cardiovascular events can occur during femoral canal preparation 3

• Confirm with the surgeon when femoral canal instrumentation begins to anticipate potential cardiovascular instability 3
• While the provided guidelines focus on cemented arthroplasty, similar embolic phenomena can occur during intramedullary nailing 3

Sedation Strategy

Minimal Sedation Approach

Use minimal or no sedation during spinal anesthesia 2

• Avoid long-acting benzodiazepines entirely as they are strongly associated with postoperative delirium 1, 7, 2
• If anxiolysis is required, use small doses of short-acting agents and titrate carefully 6
• Avoid ketamine for sedation due to significant postoperative confusion and delirium risk in elderly patients 7

Postoperative Multimodal Analgesia

First-Line Medications

Administer paracetamol (acetaminophen) 1000 mg every 6 hours as baseline analgesia 7, 2

• Add NSAIDs/COX-2 inhibitors if not contraindicated by renal function or cardiovascular disease 7
• Use rescue opioids only as needed with 20-25% dose reduction per decade after age 55 7

Regional Analgesia Extension

The femoral nerve block provides extended postoperative analgesia and reduces opioid consumption 2

• Carefully titrate intravenous morphine as rescue strategy; avoid codeine and tramadol due to adverse effects 7

Critical Pitfalls to Avoid

Dangerous Combinations

Never combine spinal and general anesthesia simultaneously as this causes precipitous intraoperative hypotension 1, 2

Medication Errors

Avoid clonidine as a spinal adjuvant due to hypotension, sedation, and bradycardia risks 7

• Do not use opioids as sole adjunct to anesthesia due to respiratory depression and postoperative confusion risk 7

Neuromuscular Blockade

If general anesthesia is used, maintain perioperative neuromuscular monitoring as duration of action is prolonged and unpredictable in elderly patients 6

• Rarely reduce intubating doses of neuromuscular blocking agents, but expect prolonged duration 6

Team Communication and Preparation

Pre-operative Briefing

Identify the patient's high-risk status during pre-list briefing and World Health Organization timeout 3

• Ensure all theatre team members understand the cardiovascular risks associated with femoral instrumentation 3
• Confirm experienced anesthesiologist supervision or direct involvement for this high-risk elderly patient 3