Association Between Transport Mode and Oxygenation Status Among Critically Ill Patients in Addis Ababa: A Cross-Sectional Study

Background In Ethiopia, underdeveloped emergency medical systems (EMS) contribute to high morbidity among critically ill patients due to inadequate prehospital oxygenation. This study examines the association between transport mode and hypoxia (SpO₂ <94%) upon emergency department (ED) arrival in Addis Ababa. Methods A prospective cross-sectional study was conducted from August 20 to October 20, 2023, at Tikur Anbessa Specialized Hospital and Zewditu Memorial Hospital. Using consecutive sampling, 202 critically ill patients (aged ≥ 14 years) triaged to the red zone (TEWS ≥ 7, GCS ≤ 8, or ABC compromise) were enrolled. Hypoxia was defined as SpO₂ < 94%. Data were analyzed using chi-square and multivariable logistic regression. Results Of 202 patients, 174 (86.1%) were hypoxic upon arrival. Prehospital oxygen was given to 63 (31.2%): nasal prongs (52, 25.7%), face mask (6, 3%), reservoir mask (2, 1%), and intubation (3, 1.5%). Ambulance transport was used in 94 (46.5%). Hypoxia was lower in ambulance (44.1%) vs. non-ambulance (55.9%) patients, but not significant (χ²=2.52, p = 0.112). Adjusted OR for hypoxia (ambulance vs other): 0.68 (95% CI 0.39–1.17), p = 0.163. Invasive ventilation was required in 43 (21.3%). Conclusion Despite 46.5% ambulance use, 86.1% of critically ill patients arrived hypoxic, with only 31.2% receiving prehospital oxygen. Enhanced EMS training, oxygen systems, and protocols are urgently needed.