Non invasive continuous positive airway pressure therapy in patients presenting with cardiogenic pulmonary odema

Abstract

Increasing attention in the last decade has shown that intervention of Continuous Positive Airway Pressure therapy (CPAP) in cardiogenic pulmonary odema (CPO) markedly improves the outcome of patients presenting with acute respiratory failure. The literature however is contradictory. Some studies show an improvement in outcome of patients receiving CPAP therapy, whilst some others show no difference in mortality and morbidity between groups treated either with CPAP or those that were intubated. CPAP is also discussed in the literature with noninvasive positive pressure ventilation. The relationship between the two in the management of acute respiratory failure is reported. Many papers discuss CPAP therapy in Critical Care Units outside emergency departments. This thesis examines the value of early intervention of CPAP in the emergency setting, and the influence experienced nurses have on early initiation of CPAP. This study researched the early application of CPAP therapy to patients presenting to a metropolitan emergency department with CPO and what difference, if any, CPAP therapy made to mortality and morbidity figures for this group. A non-experimental correlational design was selected. The data were collected by a retrospective patient record audit over a period of a year. The total number of cases recorded was 54 (n=54). Correlational and descriptive analysis was undertaken using the Statistical Programme for Social Science (SPPS). The primary outcome measures were off CPAP within two hours, transfer to Intensive Care Unit or Cardiac Care Unit and secondary outcomes measures were length of in-hospiial stay and death. There was a significant relationship between triage code and commencement of CPAP, (r = .311, n = 54, p < 0.022). Experienced nurses triage in the emergency department, recognise patients that require treatment and initiate CPAP earlier than less experienced nurses. There was a significant relationship between the nurse level and time CPAP commenced, (r = -.302, n = 54, p < 0.026). There was a trend towards more experienced nurses attending patients who required immediate treatment or treatment within ten minutes. These patients were more likely to be recognised at triage as requiring immediate attention The mean lime from patient presentation to the emergency department, to commencement of CPAP was 35 minutes. Twenty six (48%) patients were off CPAP within one hour, nine (16.7%) within two hours, ten (18.5%) were transferred to a general ward on CPAP, three (5.6%) were transferred to the Intensive Care Unit on CPAP, and five (9.3%) were transferred to the Cardiac Care Unit on CPAP. One patient required intubation in the emergency department. There was a significant relationship between CPAP outcome and initial oxygen saturation on arrival (r = -.473, n = 52, p< 0.000). CPAP therapy reduced intubation and ventilation for this group of patients. The mean length of in-hospital stay was 5.67 days. There were no deaths in the emergency department within this group, but the in-hospital mortality for patients treated with CPAP was ten (18.5%). The in-hospital mortality was lower than comparative studies, as was the mean length of stay. Earlier recognition by experienced nurses of patients presenting with CPO requiring early application of CPAP therapy would appear to have a direct relationship on reducing mortality and morbidity, and this requires further research.