Table 2.

Proposed grading [1] adverse events [21] and estimated 30-day mortality [2]

Grades of BCIS	Clinical findings (Donaldson)	Incidences of adverse events	Estimated 30-day mortality
Grade I	Moderate hypoxia (SPO2 < 94%) or Hypotension [fall in systolic blood pressure (SBP) > 20%]	~ 20%	9.3%
Grade II	Severe hypoxia (SpO2 < 88%) or Hypotension (fall in SBP > 40%) or Unexpected loss of consciousness.	~ 3%	35%
Grade III	Cardiovascular collapse requiring Cardiopulmonary Resuscitation	~ 1%	88%