Profile of non traumatic patients with indications for mechanical ventilation and their treatment outcome in the emergency medicine department of Muhimbili National Hospital

Abstract

Introduction: Mechanical ventilation is a means of providing assisted ventilation in those whose abilities to breathe are diminished or lost,and can be either invasive (intubation) or non-invasive (CPAP).Over the past decades, in the emergency departments worldwide, there has been an increase in the number of patients presenting in critical condition and mechanical ventilation is among the most important interventions for these patients. In many clinical settings, patients requiring mechanical ventilation remain at ED for prolonged periods while waiting for ICU admission. ED care in limited income countries is at its infancy and hence, little is known about the profile and outcomes of patients who present to the emergency department needing mechanical ventilation. Aim of the Study: We aimed to describe the clinical profile of patients with indications for mechanical ventilation and their outcome in the Emergency Medicine Department of Muhimbili National Hospital. Methods: This was a prospective, descriptive cohort study of consecutive adult patients presenting to Muhimbili National Hospital Emergency Medicine Department resuscitation areas (high acuity) and meeting criteria for mechanical ventilation. Data wascollected over a period of five months from August 2018 to December 2018 at the Emergency Department and followed through their hospital stay. Patient demographic data, clinical presentation, laboratory results and ED management provided were recorded using a standardized data collection form. The overall mortality, length of ED stay and length of hospital stay was calculated and risk factors for poor outcome were determined. Results: Of 4120 patients triaged to the resuscitation area, there were 107 (100%) patients with indications for mechanical ventilation. After excluding 14(13.1%) trauma patients, 93(86.9%) patients were enrolled. The median age was 53 years (IQR 36-73 years), and 47 (50.5%) were females. Among the 93 patients with an indication for mechanical ventilation 48(51.6%) received either non-invasive (CPAP) 23(47.9%) or invasive 25 (52.1%). All intubated patients were admitted to ICU, 12(25%) of those who received non-invasive ventilation were admitted to ICU, 6(12.5%) were admitted to cardiac ward, 3(6.25%) admitted to nephrology ward and 2(4.2%) admitted to the medical ward. Of the entire study sample, 28 (30.1%) patients died; 17(37.2%) were among the 45 patients who receivedno mechanical ventilation and 11(22.9%) of the 48 who received either invasive or non-invasive ventilation.However, there was no significant difference in mortality between patients who received any form of mechanical ventilation vs. those who did not receivemechanical ventilation, (p=0.125).A prolonged ED LOS (>4hrs)occurred in31(64.6%)of patients receiving mechanical ventilation and 25(55.6%) among those who did not receive mechanical ventilation. A GCS ≤8, (RR=2.914, p=0.038), being intubated (RR=8.462, p=0.034) and abnormal potassium levels (RR=4.036, p=0.005) were predictors of higher mortality. Conclusion:Among patients with indications for mechanical ventilation, there was no survival benefit for those who received mechanical ventilation, although patients receiving non-invasive ventilation were significantly more likely to survive than those who were intubated. This difference may be because the ED is more likely to intubate the sickest patients, who have a higher risk of death. Low GCS≤8 and abnormal potassium levels were also independent predictors of mortality.