Sensitivity of a preanaesthesia screening and triage tool in identifying high risk patients: A diagnostic accuracy study
Date of Award
Master of Medicine (MMed)
Dr. Shamshudin Mohammedali
Prof. Vitalis Mung’ayi
Dr. Rajpreet Bal
General Surgery (East Africa)
Introduction; Preoperative evaluation and optimization is conducted to prepare a sound perioperative management plan and limit complications. The standard of assessment is by the anesthesiologist based on ASA recommendations, and can be conducted early in the PAC or on the operative day. Reviews in the PAC have been shown to allay anxiety and reduce day of surgery cancellation. While it is ideal for all patients to be evaluated preoperatively by the physician anesthesiologist in the PAC, there are very few anaesthesiologist's in low and middle income countries meaning this may be unachievable. This creates a demand for innovative ways to conduct the preoperative assessment with judicious use of the limited services of the anesthesiologist without compromising patient care. One such method is use of triage tools to determine high risk patients that should be reviewed by an anesthesiologist. We conduct a study to determine the sensitivity of a preanaesthesia risk assessment tool in identifying high risk patients.
Methods: We conducted a prospective observational diagnostic accuracy study at the Aga Khan University Hospital, Nairobi Preanaesthesia Assessment Clinics. The primary objective was to determine the sensitivity of the PRAT in identifying high risk patients who require a review in the PAC early before their surgery. The secondary objectives included determining the specificity, negative predictive value and positive predictive value of the PRAT in identifying high risk patients. The assessment of the PRAT was examined against the anaesthesiologist’s final assessment as the standard evaluation and the sensitivity obtained via standard formula from a 2 x 2 table.
Results; Majority of the participants were female at 75.8%, young with a median age of 36(20, 74) with a mean BMI of 28.8. Most patients were classified as ASA PS I (49.2%) or II (45.3%). 94.5% of patients had attained a tertiary education. The most common procedures were Grade II Obstetric and Gynecological as per Modified John’s Hopkins Surgical Severity. There were no DOS cancellations due to medical reasons. The sensitivity of the PRAT in identifying high risk patients was 90.6%, with a specificity of 37.5%.
Conclusion; The preanaesthesia risk assessment tool has a high sensitivity in identifying high risk patients and may be used in developing a triage and referral system to the PAC. Further studies may be necessary to determine the sensitivity of this tool in populations of lower level of education and/or low health literacy levels.
Misoi, B. K. (2021). Sensitivity of a preanaesthesia screening and triage tool in identifying high risk patients: A diagnostic accuracy study (Unpublished master's dissertation). Aga Khan University, East Africa.