Multiple comorbidities for THR

61-year-old male for THR


  • BMI 56
  • OSA – severe AHI 86, can’t tolerate CPAP
  • Chronic back pain
  • Hiatus hernia


  • OSA 
    • HCO3 normal, unlikely to have obesity hypoventilation syndrome
    • SpO2 on RA 97%
    • Patient cannot tolerate mask
    • Limited scope for optimisation apart from weight loss
  • BMI 56
    • Likelihood of preoperative weight-loss small.
    • Evidence for weight loss strategies points to gastro-reductive surgery, but extremely limited public availability (especially with absence of metabolic syndrome) and expensive in the private sector.
    • There is merit at face value for preoperative weight loss, but no clear evidence to suggest improved outcomes.
    • Unusual that patient was offered surgery at this BMI.  See table below, obesity and smoking only co-morbidities with RCT evidence to support increased perioperative risk.
    • Reviewed by cardiologist. Sestamibi normal. TTE showed diastolic dysfunction (diuretics commenced)
    • SOB thought to be multifactorial – diastolic dysfunction, obesity, deconditioning. 
    • Nil further cardiac investigations thought necessary by cardiologist

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  • Proceed with surgery
  • Encourage compliance, where possible, with CPAP
  • ICU level 3
  • Neuraxial technique and minimal sedation recommended.