مقايسه شاخصهاي جداسازي CROP و RSBI در پيش بيني نتيجه قطع تهويه مكانيكي در بيماران آي سي يو

Comparison between CROP and Rapid Shallow Breathing index as predictors of weaning in predicting the outcome of discontinuation from mechanical ventilation in ICU patients

مقدمه با توجه به اينكه يك شاخص با صحت تشخيصي بالا مي­تواند بيماران آماده براي جداسازي از ونتيلاتور را به درستي شناسايي كند و از بروز جداسازي زودرس و عوارض آن جلوگيري نمايد اين مقاله با هدف مقايسه دو مورد شاخص CROP و RSBI و بررسي ارزش تشخيصي آنها در پيش بيني نتيجه جداسازي از ونتيلاتور انجام شد. روش كار مطالعه حاضر به روش آينده نگر يك سو كور بر روي 80 بيمار بستري در سه آي سي يو(داخلي-عمومي–سكتههاي مغزي) بيمارستان قائم(عج) مشهد از مهر سال 1394 تا ارديبهشت سال 1395انجام شد. واحدهاي پژوهش بعد از احراز شرايط ورود به مطالعه در يك گروه مورد بررسي قرارگرفتند. همه بيماران آماده براي جداسازي از ونتيلاتور به مدت 30 دقيقه تحت تهويه با مد حمايت فشاري با حمايت حداقل قرار گرفتند. در صورت ثبات علايم حياتي در طي اين 30 دقيقه پارامترهاي مورد نياز براي محاسبه شاخصها بوسيله ونتيلاتور اندازهگيري و گازهاي خون شرياني اندازهگيري و ثبت شد. سپس تمرين تنفس خود به خودي به مدت 120 دقيقه با قطعه تي انجام شد. در نهايت بر اساس نتيجه جداسازي و پيش بيني شاخصها، قدرت تشخيصي شاخصها مورد ارزيابي قرار گرفت. نتايج تعداد 57 مورد جداسازي موفق و 23 مورد جداسازي ناموفق وجود داشت. حساسيت شاخصهاي CROP و RSBI به ترتيب 85% و 98/2% و ويژگي آنها به ترتيب 75% و 26% بود. صحت تشخيصي شاخص (CROP (%85/2 از شاخص RSBI بيشتر بود. نتيجه­ گيري شاخص CROP داراي بيشترين صحت تشخيصي بود و حساسيت و ويژگي آن بالا بود. نقطه برش شاخص جداسازي RSBI به همه بيماران با اتيولوژيهاي مختلف قابل تعميم نمي­ باشد.

Background: Usage of indicators to predict the outcome of weaning from the ventilator is a controversial issue. An index with high diagnostic accuracy can properly identify the Patients ready for weaning from mechanical ventilation and prevents premature weaning and its complications. Two of the introduced weaning indicators are RSBI and CROP but their predictive value in predicting the outcome of weaning from mechanical ventilation is different or contradictory. Objectives: This study was to Compare RSBI and CROP in predicting the outcome of weaning from mechanical ventilation in patients admitted to ICU. Materials and methods: This prospective, single-blind study was performed on 80 adult patients who were on mechanical ventilation for more than 24 hours in 3 ICUs (Internal-General-stroke) of Mashhad Ghaem hospital from October 2015 to May 2016. All the patients ready for weaning were identified and studied in one group. All of them were ventilated with PSV mode with minimum support for 30 mins. If the patient’s vital signs were stable during those 30 mins, we measured the required respiratory variables and arterial blood gas values to calculate CROP and RSBI. Then the SBT was performed, with a T-piece for 120 mins. finally the diagnostic accuracy of each index was evaluated according to the weaning outcome and prediction of indexes. Results: There were 57 successful and 23 unsuccessful weaning cases. The specificities were CROP 0.85 and RSBI 98.2. The sensitivities were CROP 0.75 and RSBI 0.26. The diagnostic accuracy were CROP 85.2 and RSBI 77.5. The new threshold value obtained in this study was very different for RSBI. CONCLUSIONS: According to the analysis performed by the cut-off points obtained in previous studies, CROP index has the highest diagnostic accuracy, sensitivity and specificity were both high. The cut-off point of RSBI previously reported for non-homogeneous patients population is not extensible to all with different etiologies.