H.F. DEMİR, K. DEMİRAĞ, C. BOR, M. UYAR, F.O. ERİŞ

Weaning uygulanan yoğun bakım hastalarında PSV ile MRV modlarının metabolik parametreler üzerine etkisi

Amaç: YB hastalarının yaklaşık %90ı mekanik ventilasyon desteğine ihtiyaç duyar. Uzamış mekanik ventilasyon morbidite ve mortaliteyi arttırmaktadır. Mekanik ventilasyondan ayrılma (weaning) bu nedenle çok önemlidirÇalışmamızın hipotezi; weaning döneminde mandatory rate ventilation (MRV)nin, pressure support ventilation (PSV)ye göre, metabolik parametreler üzerinde daha olumlu etkisi olacağıdır. Bu amaçla metabolik parametrelerden oksijen tüketimi (VO2), karbondioksit üretimi (VCO2) ve enerji tüketimi (EE) ölçülerek karşılaştırıldı. Gereç ve Yöntem: Çalışmamızda 18 hasta dahil edildi. Hastalar kontrole modda iken indirekt kalorimetri cihazı ile bazal metabolik ölçüm yapıldı. Sonra hastalar randomize olarak PSV veya MRV modlarından birine ayrıldı. Hastalar toplam 60 dakika süresince izlendi. Solunum sayısı (SS), solunum mekanikleri, VO2, VCO2 ve EE değerlerkaydedildi. Bulgular: Tüm metabolik parametreler her iki grupta bazal ölçümden sonra anlamlı artış gösterdi, fakat % değişim açısından gruplar arasında farklılık gözlenmedi. İstatistiksel anlamlılık olmamakla birlikte, 30. dakikadan sonra metabolik parametrelerin PSV grubunda yükselmeye devam ederken MRV grubunda stabil olduğu belirlendi. Sonuç: İstatistiksel anlamlılık olmamakla birlikte klinik olarak MRVnin weaning uygulanan hastalarda PSVye göre metabolik açıdan daha stabil koşullar sağladığı kanaatine varıldı.

The effect of PSV and MRV modes on metabolic parameters in ICU patients weaning from mechanical ventilation

Aim: Ninety percent of patients in the ICU require mechanical ventilation. Prolonged mechanical ventilation increases mortality and morbidity. Weaning is therefore very important. The hypothesis of our study is that mandatory rate ventilation (MRV) mode has a better effect on metabolic parameters than pressure support ventilation (PSV). For this aim the oxygene expenditure (VO2), produced carbondioxide (VCO2), and Energy expenditure (EE) values were measured. Materials and Methods: Eighteen were included in the study. Basal metabolic measurements were performed with an indirect calorimetry device. Patients were randomly seperated in either PSV or MRV groups. Patients were observed for 60 minutes. Respiratory rate (RR), respiratory mechanics, VO2, VCO2, and EE values were recorded. Results: MRV group. All metabolic parameters increased in both groups after the basal measurement but there werent any significant difference between groups regarding percent of change. Metabolic parameters in the MRV group stabilised after the first 30 minutes, while they continued to increase in the PSV group. Conclusion: As conclusion, statistically there was no difference, but clinicaly MRV was found to produce more stabile metabolic parameters in weaning patients compared with PSV.

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