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Abstract Mechanical ventilation is an essential therapy in the ICU, and a large percentage of the ICU patient population will need this therapy during their ICU stay. Weaning from mechanical ventilation remains to be a cumbersome process that occupies a large percentage of the total ventilation time of the patients. Failure to predict readiness for weaning from mechanical ventilation may result in prolonging mechanical ventilation or premature weaning resulting in complications. The weaning process remains to be a subjective decision made by the physician in charge of the patient. Multiple parameters and indices have been developed and studied over the years in order to improve and unify the weaning process and to try and develop a unified index/score, that is easily obtained and does not require invasive maneuvers or put that patient at risk to obtain, that could assess the patients’ respiratory system performance and readiness to be weaned from mechanical ventilation. Old respiratory indices and parameters, such as the respiratory rate, tracheal occlusion pressure, partial pressure of arterial carbon dioxide, CORE index, CROP index and oxygen saturation, still do not meet the required performance in evaluating the respiratory system performance and accurately predicting the patient’s readiness to be weaned and successfully extubated from invasive mechanical ventilation. The integrative weaning index (IWI) was developed in order to incorporate different respiratory system measurements in order to evaluate the overall all respiratory system performance and predict successful weaning from mechanical ventilation. It was initially studied on a small patient population number and compared to the traditional weaning indices and showed promising results. It was later modified to be called the modified integrative weaning index (mIWI) and to use the pulse oximetry oxygen saturation instead of arterial oxygen saturation and showed a significant statistical difference. The index was also studied further by other authors and in comparison with the traditional indices in different patient populations, demographics and with different weaning protocols. Results from previous studies revealed that the modified integrative weaning index’s performance is comparable, yet even superior to the performance of the traditional weaning indices, specifically the rapid shallow breathing index. A set value was set for the index as it was first studied, yet further studies showed different values for the index at which better results might be obtained. Some of the performed studies, despite the superior performance of the modified integrative weaning index, did not recommend using the index. The aim of this study was to validate the performance of the modified integrative weaning index in comparison to the traditional weaning indices and with the results of previous authors, to assess if the index showed a superior performance in predicting the weaning outcome of mechanically ventilated patients in the ICU and assess the respiratory system. In this study 400 patients were selected according to the specified inclusion and exclusion criteria and were determined to be ready to be weaned from mechanical ventilation. The patients had to be on mechanical ventilation for no less than 48 hours, for any cause. Out of the 400 patients 317 were successfully weaned from mechanical ventilation and weaned with no need to return to mechanical ventilation, whether invasive or non-invasive for 48 hours. The patients were weaned and extubated according to the physician in charge’s decision based on the weaning criteria of the institution and the values for the weaning indices, included the modified weaning index, were recorded during to the weaning, extubation and post-extubation periods. The modified weaning index was not tested alone to ensure the patient safety according to the end-points and weaning criteria of the ICU. This study showed that the modified weaning index’s performance was superior to the traditional weaning indices and that its performance was similar to previous studies in predicting weaning success from mechanical ventilation, despite using a larger population of patients with wider demographics and etiologies. It also revealed that it accurately estimated the performance of the respiratory system. It is advised to use this index in conjunction with other weaning indices when weaning patients from mechanical ventilation. It cannot be used as a sole index in the everyday clinical situation as traditional indices cannot be overlooked. All the weaning indices may be able to assess the respiratory system performance and predict weaning success, however they do not accurately predict extubation success. |