Table 1

Included and excluded types of complications

‘Medical’‘Surgical’
Included a priori as potentially preventable if resulting in LOS ≥4 or 30 days readmission*:
  • Myocardial infarction

  • Unstable angina

  • Heart failure

  • Cardiac arrhythmia (LOS >4 days or after discharge but ≥7 days after surgery)

  • Cerebral stroke/transient cerebral ischaemia

  • Delirium/psychosis

  • Venous thromboembolic events

  • Pneumonia/acute worsening of chronic obstructive disease

  • Sepsis without wound infection

  • Unexplained infection

  • Falls

  • Renal infection with increase in creatinine and fluid/diuretic treatment only

  • Fluid/electrolyte derangement treated with

  • fluids only

  • Renal infection resulting in dialysis

  • Mobilisation issues preventing fulfilling functional discharge criteria within 4 days or need of inhospital rehabilitation after discharge

  • Opioid-related side effects

Included a priori as potentially preventable if resulting in LOS >4 or 30 days readmission:
  • Hip dislocation not caused by falling

  • Knee manipulation under anaesthesia

  • Wound infections with antibiotic treatment

  • Superficial infection with wound incision

  • Deep infection with removal of prosthetic components

Included for further evaluation on preventability:
  • Unexplained hypotension/hypertension

  • Unexplained fainting or dizziness

  • Unexplained dyspnoea

  • Constipation unrelated to opioids

  • Complications related to existing comorbidity†

  • Any condition not fitting other descriptions

Included for further evaluation on preventability:
Excluded a priori as being potentially preventable by perioperative intervention:
  • No recorded morbidity (LOS >4 days only)

  • Postoperative ileus

  • Diarrhoea

  • Disproved venous thromboembolic event

  • Disproved myocardial infarction

  • Disproved wound infection

  • Social considerations

Excluded a priori as being potentially preventable by perioperative intervention:
  • Postanaesthetic complications

  • Periprosthetic fracture without recorded trauma

  • Revision due to prosthetic malfunction

  • Other planned reoperations

  • Systemic arterial thrombosis/pseudoaneurism

Excluded a priori due to lack of information necessary for qualified evaluation:
  • Gastric ulcer/gastritis

  • Urinary retention

  • Uncomplicated urinary tract infection

  • Pain

Excluded a priori due to lack of information necessary for qualified evaluation:
  • Major postoperative haematoma/swelling

  • Major intraoperative bleeding

  • Minor wound bleeding

  • *Anaemia requiring blood transfusion despite no recorded major intraoperative bleed.

  • †For example, difficulties with vitamin K or antihyperglycaemic treatment, management of sleep apnoea.

  • LOS, length of stay.