63yo male for removal of L3/4 hardware, L1/2 and L2/3 extreme lateral interbody fusion, posterior fixation T10 – pelvis. Multiple previous surgeries. Severe pain and dysfunction.
- Myasthenia gravis
- Bulbar symptoms, swallowing difficulty, fatigues with mobilization
- Relapse in 2019 when steroids weaned below 30mg/d pred.
- No spirometry available
- Angiogram 2019 – 40% mid-LAD stenosis (performed for atypical chest pain)
- TTE – nil major abnormalities
- HTN & Dyslipidaemia
Issues and discussion:
- Should surgery proceed?
- Reason for OT unclear during meeting.
- High dose steroids -> concerns about bone quality and wound healing
- Further myocardial perfusion imaging?
- 40% mid LAD lesion previously.
- Low exercise tolerance due to MG and spinal issues, unable to quantify
- Will need to cease aspirin perioperatively
- Unlikely to change management.
- Cell salvage?
- Nil obvious contraindications
- With multi-level, long duration spinal surgery patient seems at high risk of significant bleeding.
- Level of postop care?
- Preoperative lung function studies required
- Factors predictive of postop MG crisis and requirement for postop vent (UpToDate)
- Vital capacity <2
- Duration of MG greater than 6yrs
- Pyridostigmine dose > 750mg/d
- History of chronic pulmonary disease
- Preoperative bulbar symptoms
- History of myasthenic crisis
- Intraoperative blood loss > 1000ml
- Serum anti-acetylcholine receptor antibody >100nmol/ml
- More pronounced decremental response (18-20%) on low frequency repetitive nerve stimulation.
- ICU level pending lung function studies
- Discussed with surgeons.
- If cell salvage is feasible/required – awaiting response
- Indication for surgery and high-risk nature of patient – extensive discussions about this patient at spinal MDT. Two surgeons involved in case. Aware of the risks. Surgery felt to be necessary.
- For discussion with cardiologist – requirement for stress imaging, and if postoperative ECG or troponin screening indicated.