Epidemiology and clinical outcomes of acute lung injury

Aim: ALI/ARDS, a severe restrictive syndrome is responsible of high mortality and morbidity in intensive care units (ICU). It is known that age, cause of acute lung injury, chronic comorbid illnesses, acute organ failures, severe sepsis/septic shock, pneumothorax, range of admission PaO2/FiO2 ratio and pH level, SOFA, SAPS2, APACHE II scores are determinants of acute lung injury prognosis. According to our Medline search we found any study about ALI/ARDS nor concerning survival factors from Turkey. The aim of this study was to share our experince concerning ALI/ARDS and the prognostic factors affecting mortality and morbidity in our University Hospital?s Medical Intensive Care Unit.Method: Patients with ALI or ARDS diagnosed between January 2006 and December 2008 in our Medical ICU of Dokuz Eylül University Hospital, were included in this retrospective cohort study. The medical records and the electronic database of the ICU were reviewed. Mortality rate of ALI/ARDS patients and prognostic factors affecting mortality were evaluated.Result: From 842 patients admitted in the ICU between these dates, 629 were mechanically ventilated. Of 629 patients 12,4 % (n:78) had ALI and 13,5 % (n:85) had ARDS. A total of 163 patients were eligible. In a mean period of 42,8 hours 51,3 % of ALI patients (n:40) respiratory conditions degraded to ARDS. Chronic obstructive pulmonary disease (COPD) (p=0,024) and chronic sentral nervous sistem illnesses (p=0,016) favorized this progression from ALI to ARDS. The mortality of patients with ARDS was significantly higher than ALI patients (67,1 % vs 24,4 % , p<0,0001). Moreover, the mortality of ARDS patients at admission compared to ALI patients degraded to ARDS was also significantly higher (67,1 % vs 47,5 %, p=0,037). In both ALI (65,4 %) and ARDS (76,5 %) groups, acute lung injury was encountered more frequently when lungs are the primary cause of disease. Age (p=0,030), CRP level (p=0,011), immunodepression (p=0,010), cirrhosis (p=0,010), COPD (p=0,006), chronic sentral nervous sistem illnesses (p=0,048), acute renal failure (p=0,033), encefalopathy (p=0,0002), severe sepsis/septic shock (p=0,045) were factors affecting motality in ALI patients while age (p=0,029), CRP level (p=0,016), initial PaO2/FiO2 level (p=0,0001), primary ARDS (p=0,008), chronic heart illnesses (p=0,045), cirrhosis (p=0,014), acute cardiac failure (p=0,002), encephalopathy (p=0,012), severe sepsis/septic shock (p=0,020) were factors affecting motality in ARDS patients. In both ALI (p=0,528) and ARDS (p=0,357) patients decreased pH level due to permissive hypercapnoea did not affect mortalty.Conclusion: ALI and ARDS are engraved with severe mortality and morbidity and are a frequent diagnostic in ICU. More than half of ALI patients rapidly degraded to ARDS tought doubled the risk of fatal outcome. Comorbid conditions such as COPD, Alzheimer?s disease, Parkinson?s disease, chronic cerebrovascular illness facilitated this degradation to ARDS. Early diagnosis in ward, early intensive care support, lung protective ventilation strategies and permissive hipercapnea reduced mortality. Acute lung injury ocurred from primary pulmonary insult, age, chronic comorbid illness, non pulmonary acute organ failures especially those associated with severe sepsis/septic shock had major fatal impact. Decreased PaO2/FiO2 ratio at the time of admission, lung injury?s severty were directly correlated to mortality hence are determinants for the prognosis.Keywords: Acute Lung Injury, Adult Respiratory Disstres Syndrome, Epidemiology, Prognostic Factors, Mortality, Lung Protective Mechanical Ventilation and Permissive Hypercapnea