Predicting perioperative risk in patients in aged 90-100 years.

In this study we will first be observing postoperative complications in patients aged 90-100 years who have undergone any surgical procedure or intervention at Austin Health between 1 January 2012 to 31 December 2019. As this is a retrospective study, there is no participant involvement. Only the de-identified hospital medical record of patients who have had surgery will be reviewed. Second, we will then assess if the age-adjusted Charlson Comorbidity Index (CCI) can be applied to the nonagenarian surgical population. Our study presents the validity of age-adjusted CCI for nonagenarian patients across multiple surgical and endoscopic streams, whilst proposing a modified score in improving perioperative risk assessment for this vulnerable population. The Charlson Comorbidity Index is a validated risk score for clinicians in predicting perioperative mortality and morbidity in comorbid patients. First introduced by Professor Mary Charlson and her peers in 1987, the CCI assesses comorbidity level through the number and severity of 19 pre-defined comorbid conditions. Scores are weighted accordingly for each disease and their severity. Charlson et al, subsequently established a refined tool with the Age-Adjusted Charlson Comorbidity Index (ACCI) in 1994, adjusting the existing CCI score for increasing age. The ACCI has subsequently been validated in predicting short term and long-term outcomes including mortality, function outcomes and hospital length of stay across different surgical populations. The CCI has since become one the most widely used scoring system for comorbidities by clinical researches for longitudinal studies and by point of care clinicians.