Evaluation of Medication Errors among Inpatients in a Tertiary Government Hospital's Pulmonary Medicine Service: A Cross-sectional Retrospective Study.

Background and objective: Medication errors pose substantial risks in hospitals, particularly concerning patient safety. These errors, occurring throughout the medication use process, are one of the most common causes of morbidity and mortality in clinical practice. In the Philippines, there is a lack of evidence on the prevalence and effects of medication errors, emphasizing the need for further investigation. This study evaluated the prescribing, transcribing, and monitoring errors among inpatients under the Pulmonary Medicine Service of the Department of Medicine in the Philippine General Hospital.

Methods: This cross-sectional retrospective records review used the total population purposive sampling technique to examine eligible charts of inpatients with asthma and/or COPD from August 1 to December 31, 2022. The frequency, type, and severity of medication errors were determined. Linear regression and Cox proportional hazards models were used to examine the relationship between patient-related factors and medication errors, and length of hospital stay and mortality.

Results: Fifty (50) out of 226 medical records were processed and analyzed. Included patients were predominantly older male adults. More than twothirds of the patients were diagnosed with COPD while approximately one-fourth suffered from asthma. All patients were practicing polypharmacy and the vast majority presented with comorbidities. A total of 6,517 medication errors, predominantly prescribing errors (99.1%), were identified. Despite the high prevalence of medication errors, the majority were classified as "error, no harm" (98.8%), while only 1.17% were deemed as "error, harm." As the frequency of prescribing errors increases in the power of three (rough approximation of e), from 1 to 3 to 9 to 27, etc., the expected hospital stay increases by 2.078 days (p <0.001) (e.g., 3² = 9 errors with LOS of around 4 days); meanwhile, more severe transcribing errors increase the length of stay by 4.609 days (p = 0.034) All independent variables were noted to have a lack of significance and thus no meaningful patterns in the data related to patient mortality were identified, primarily due to the insufficient amount of observed mortality in the included sample.

Conclusion: All eligible patient charts had at least one medication error, with the majority being prescribing errors. Among the variables, prescribing errors significantly affected the length of stay, while severity of transcribing errors had a marginally significant effect. It is essential to develop comprehensive education and training initiatives and adopt a systematic approach to mitigate medication errors and promote patient safety.