摘要：Introduction: Mechanical ventilation has important role in improvement the patient,s ventilation and oxygenation that their respiratory condition is poor. Nevertheless it can accompany with innumerous unfavorable complications. ICU scoring systems have been offered for rapid and proper weaning patients from mechanical ventilation and outcomes prediction also Apache II scoring system has earned public acceptability. As regards the importance of weaning outcomes prediction، researcher investigated research: The role of Apache II scoring system in prediction outcomes from mechanical ventilation in patients have been hospitalized in Mashed Emam Reza، Ghaem and Shahidkamyab ICU wards. Methods: This prospective and descriptive study was done on 300 hospitalized patients in medical، surgical and trauma ICU wards in six months period. Information about the cases was recorded in questionnaire، information about the Knaus Apache II form (1985) that has been revised in 1999 include three sections: Acute physiology score، age adjustment and chronic health adjustment gathered in two times: The first admission 24 hours and complete weaning time. Results: The association of first admission 24 hours Apache II scores and outcomes (survivor and died) (t=2.86، P<0.005) ، complete weaning time Apache II score and outcomes (t=22.89، P<0.0001) ، and difference between two stages Apache II score and outcomes (t = 25.78، P< 0.0001) confirmed also the results showed that Apache II score> 28 in first admission 24 hours has maximum sensitivity (71%) and specificity (69%) than another scores. In this research Apache II scoring system showed: sensitivity (81%) ، specificity (80%) ، positive indicative value (79%) and negative indicative value (82%). Conclusion:The results of research hopfully attracts education and research administrators and managers to proper and rapid weaning patients from mechanical ventilation according to better ICU scoring system there upon leading to rapid and safe discharge and low patients mortality in ICU.
