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Orthopedic — TJA, Scoliosis, Hypotension
TEXTSpecialty II · 10 min read
TJA opioid-sparing + scoliosis MEP-friendly + tourniquet + cement implantation — the four ortho-specific anesthetic challenges.
After this lesson you can
3 min read7 sections- Plan tourniquet management.
- Identify methemoglobinemia risk in regional.
- Anticipate fat embolism syndrome.
- Recognize compartment syndrome early.
TJA regional + opioid-sparing
Preserves quad strength earlier ambulation + lower fall risk.
Discharge POD#1-2 standard.
Total hip: spinal + multimodal + LIA (local infiltration anesthesia) by surgeon.
Lumbar plexus block alternative.
Scoliosis — TIVA + blood loss
NMB only at intubation.
Antifibrinolytic: TXA 30 mg/kg load + infusion.
Cell saver.
Controlled hypotension cautiously (MEP concerns).
Pediatric scoliosis blood volume small relative to EBL — transfuse early.
Postop ICU monitoring + multimodal analgesia.
Length of surgery 4-8 hr typical positioning concerns critical.
Methemoglobinemia from prilocaine
EMLA cream (lidocaine + prilocaine): large surface area or infant skin = higher absorption + MetHb risk.
SpO₂ plateaus at ~85% regardless of true SaO₂.
Co-oximetry confirms.
Treatment: methylene blue 1-2 mg/kg IV (avoid in G6PD — use ascorbic acid 1.5 g IV q4h).
Pediatric population highest risk.
DVT prophylaxis timing
LMWH 12-24 hr post-spinal/epidural.
DOACs 24 hr post-spinal.
Catheter removal timing matches placement timing (re-dose only after catheter out).
Mechanical prophylaxis (SCDs) throughout admission.
Earliest pharmacologic anticoagulant timing depends on bleeding risk + thrombosis risk + neuraxial technique.
Coordination with ortho team mandatory + documented in plan.
Hip fracture in elderly
Surgery within 24-48 hours improves outcomes.
- REGAIN trial (NEJM 2021) showed equivalent 60-day outcomes for spinal vs GA — choose based on patient comorbidity
- anticoagulation
- surgeon preference
SPINAL with light or no sedation may be preferred in delirium-prone elderly (avoid benzo, dexmedetomidine acceptable adjunct).
Pre-op fascia iliaca compartment block (FICB) or PENG block excellent for transport + positioning analgesia + reduces opioid.
Frailty assessment guides ICU admission decision.
Tourniquet — physiology + management
100 mmHg above SBP for upper extremity, ~150 above SBP for lower extremity.Older fixed-pressure protocols (250 upper, 350 lower) are obsolete in many practices.
- develops
30-45 minpost-inflation - C-fiber mediated
- often refractory to opioid alone — supplement with regional or accept the increased anesthetic depth
- K spike
- lactic acid
- ETCO2 rise
- transient hypotension from rapid washout — hyperventilate just before release
Bone cement implantation syndrome (BCIS)
SEVERITY range: mild (transient hypotension, often unnoticed) to severe (cardiac arrest).
- vent the femoral canal (surgeon-dependent)
- slow cement injection
- suctioning the canal during injection
- vigilant monitoring around cement time
- epinephrine drawn + ready
- communicate with surgeon at the cement-injection moment
⚠ Common pitfalls
- Tourniquet >2 hr — releases ischemic metabolites + may cause neuropraxia.
- Prilocaine for IVRA in setting of MetHb risk — dose-dependent.
- Femoral block masking compartment syndrome — pain is the cardinal sign; use lighter block.
- Skipping DVT/PE prophylaxis after TJA — risk peaks 7-14 days post-op.
💎 Clinical pearls
- Tourniquet release: ↓BP + ↑HR + ↑ETCO₂ — anticipate with fluid + vasopressor.
- Fat embolism syndrome: dyspnea + petechiae + neuro changes 24-72 hr post long-bone fx.
- Multimodal pain after TJA: spinal + adductor canal + acetaminophen + NSAID + opioid PCA.
- Methylene blue 1-2 mg/kg for MetHb >25% or symptomatic.
Recap
- Tourniquet release: ↓BP + ↑HR + ↑ETCO₂ — anticipate with fluid + vasopressor.
- Fat embolism syndrome: dyspnea + petechiae + neuro changes 24-72 hr post long-bone fx.
- Multimodal pain after TJA: spinal + adductor canal + acetaminophen + NSAID + opioid PCA.
- Methylene blue 1-2 mg/kg for MetHb >25% or symptomatic.
Mark each section done to complete the module.