How should an acute fracture be managed in a severely hypotensive patient dependent on norepinephrine with impaired renal function (creatinine clearance ≈ 32 mL/min)?

Management of Acute Fracture in a Severely Hypotensive Patient on Norepinephrine with Renal Impairment

This patient requires damage-control orthopaedics with delayed definitive surgery after hemodynamic stabilization, as they meet criteria for "unstable clinical status" with severe circulatory shock requiring high-dose norepinephrine. 1

Initial Risk Stratification

This patient's clinical profile places them in the high-risk category requiring damage-control orthopaedics rather than immediate definitive surgery 1:

• Severe circulatory shock: Norepinephrine dependency indicates severe hemodynamic instability 1
• Impaired renal function: CrCl ≈32 mL/min represents significant renal dysfunction 1
• Unstable clinical status: According to the 2021 severe limb trauma guidelines, patients requiring vasopressor drugs (norepinephrine >4 mg/h) are classified as having "severe circulatory shock" and unstable clinical status 1

Immediate Surgical Management Strategy

Perform temporary fracture stabilization (damage-control orthopaedics) followed by safe delayed definitive surgery once hemodynamically stable 1:

• Apply external fixation or splinting for mid-term stabilization rather than proceeding with definitive internal fixation 1
• Delay definitive orthopaedic surgery until the patient achieves stable clinical status 1
• The goal is to prevent the "second hit" phenomenon where major surgery in an unstable patient worsens outcomes 1

Hemodynamic Optimization Protocol

Vasopressor Management

Continue norepinephrine as first-line vasopressor while optimizing fluid status 2, 3:

• Target mean arterial pressure (MAP) ≥65 mmHg 2, 3
• Ensure adequate volume resuscitation with crystalloids (minimum 30 mL/kg) before or concurrent with vasopressor therapy 3
• Preferentially use central venous access to minimize extravasation risk 3
• Monitor blood pressure every 5-15 minutes during titration 3

Avoiding Intraoperative Hypotension

Intraoperative hypotension is an independent risk factor for postoperative acute kidney injury in hip fracture patients 4, 5:

• Maintain MAP >65 mmHg throughout the perioperative period 4
• Use invasive arterial blood pressure monitoring for continuous assessment 1
• Consider additional hemodynamic monitoring (cardiac output-guided fluid therapy) in high-risk patients 1

Renal Protection Strategies

Fluid Management

Optimize fluid therapy to reduce morbidity while protecting renal function 1:

• Use cardiac output-guided fluid administration to reduce hospital stay and improve outcomes 1
• Avoid hypovolemia, which exacerbates norepinephrine-induced vasoconstriction and organ hypoperfusion 3
• Monitor urine output targeting >50 mL/h as a marker of adequate perfusion 3

Norepinephrine and Renal Function

Norepinephrine does not inherently worsen renal function when used appropriately in adequately volume-resuscitated patients 6, 7:

• Studies demonstrate that norepinephrine improves renal blood flow and GFR in vasodilated states by increasing renal perfusion pressure 6, 7
• However, both intraoperative hypotension AND cumulative norepinephrine dose are independently associated with postoperative AKI 8
• The key is avoiding both profound hypotension and excessive norepinephrine doses 8

Pain Management in Renal Impairment

Regional Anesthesia as Primary Modality

Use femoral nerve blocks or fascia iliaca compartment blocks as the primary analgesic approach 9:

• Regional anesthesia provides superior pain control with fewer systemic side effects 9
• Continuous catheter techniques are preferred over single-shot blocks 9
• Regional anesthesia may reduce DVT risk and facilitate early mobilization 1

Systemic Analgesia

Acetaminophen 1000 mg IV/PO every 6 hours is mandatory baseline treatment 9:

• Significantly decreases supplementary opioid requirements 9
• Safe in renal impairment at standard doses 1

NSAIDs are absolutely contraindicated with any degree of renal dysfunction 1, 9:

• CrCl 32 mL/min represents moderate-to-severe renal impairment 1

Opioids must be used with extreme caution and dose-reduced 1:

• Avoid oral opioids entirely 1
• Reduce IV opioid dose and frequency by 50% 1
• Never use codeine (constipating, emetic, causes cognitive dysfunction) 1
• If opioids are necessary, hydromorphone dose should be reduced by 50-75% 9

Timing of Definitive Surgery

Delay definitive surgery until hemodynamic stability is achieved 1:

• The 48-hour target for hip fracture surgery applies to stable patients 1
• In unstable patients, delaying surgery for physiological optimization is appropriate 1
• Benefits of expedited surgery must be balanced against risks of operating on unstable patients 1

Criteria for Proceeding to Definitive Surgery

Transition to definitive surgery when the patient achieves stable clinical status 1:

• Stable circulatory status with no or minimal vasopressor requirements (norepinephrine <2 mg/h) 1
• Lactate <2.5 mmol/L 1
• Adequate urine output maintained 1
• Improving or stable renal function 1

Perioperative Considerations

Anesthetic Technique

Regional anesthesia is preferred when feasible 1:

• Reduces risk of DVT and may improve outcomes 1
• Facilitates early mobilization and postoperative physiotherapy 1
• However, in severely unstable patients, general anesthesia with invasive monitoring may be necessary 1

Monitoring Requirements

Enhanced monitoring is mandatory for high-risk patients 1:

• Invasive arterial blood pressure monitoring 1
• Central venous pressure monitoring if using high-dose vasopressors 1
• Continuous ECG, oxygen saturation, temperature 1
• Arterial blood gases and lactate as markers of tissue perfusion 2

Bone Cement Considerations

If cemented arthroplasty is eventually required, take precautions against bone cement implantation syndrome (BCIS) 1:

• Increase inspired oxygen to 100% at time of cementation 1
• Ensure adequate intravascular volume before cementation 1
• Use enhanced hemodynamic monitoring 1
• Optimize surgical technique (medullary lavage, cement gun, femoral venting) 1

Critical Pitfalls to Avoid

Do not proceed with immediate definitive surgery in this unstable patient 1:

• High-risk patients require damage-control orthopaedics, not early definitive surgery 1
• Operating on severely hypotensive patients increases mortality and morbidity 1

Do not use NSAIDs for pain control 1, 9:

• Absolutely contraindicated with CrCl 32 mL/min 1

Do not use standard opioid doses 1:

• Requires 50% dose reduction and avoidance of oral formulations 1

Do not allow intraoperative hypotension 4, 5, 8:

• Independent risk factor for postoperative AKI 4, 5, 8
• Maintain MAP >65 mmHg throughout 4

Do not use excessive norepinephrine doses 8:

• Both hypotension AND high cumulative norepinephrine doses independently increase AKI risk 8
• Balance is required between maintaining pressure and minimizing vasopressor exposure 8