A prospective study of pre-operative risk factors associated with extended length of stay in patients attending a pre-operative clinic in South Africa

Background Preoperative assessment clinics play a critical role in identifying, evaluating, and mitigating perioperative risks. Despite global data highlighting the importance of preoperative risk factors on surgical outcomes, there remains limited information on their impact on postoperative length of stay in South African contexts. Objectives This study aimed to describe the demographic and clinical profiles of patients referred to a preoperative clinic in Johannesburg, South Africa, and to examine factors associated with postoperative length of stay (LOS). Methods This was a prospective cohort study conducted between 2021 and 2022 at a private clinic. Patients aged ≥18 years undergoing non-cardiac surgery were included. Data on demographics, comorbidities, surgical procedures, and clinical outcomes were collected. Statistical analysis was performed to assess relationships between preoperative risk factors, including ASA grading, Revised Cardiac Risk Index (RCRI), eGFR, Diabetes Mellitus, age, obesity and LOS. Results A total of 214 patients were assessed, of which 75.7% were female, with a median age of 62.5 years. Common comorbidities included hypertension (59.3%) and obesity (55%). The median LOS was 3.5 days, with 47.2% of patients staying more than 3 days postoperatively. Knee (33.2%) and hip surgeries (21%) were the most common procedures. A significant association was found between longer LOS and RCRI score ≥1 (p=0.007), as well as renal dysfunction in knee surgery patients (p=0.027) and age in patients undergoing hip surgery (p=0.049). There was no significant association between ASA grade, presence of diabetes mellitus, eGFR, age or obesity. Conclusions Increased RCRI scores, renal dysfunction, and age were associated with prolonged hospital stay. Findings highlight the need for targeted interventions in preoperative care to reduce LOS, particularly for high-risk patients. Further research is needed to validate these results across broader healthcare settings and to establish appropriate protocols for South African patients undergoing pre-operative assessment.