1. Xu Xiaoting, Zhang Junyi，Chang Wei，Sun Qing，Yang Yi，Qiu Haibo,Liu Ling
Correlation between muscle specific microRNA in plasma and diaphragmatic dysfunction in patients undergoing mechanical ventilation
Xu Xiaoting, Zhang Junyi，Chang Wei，Sun Qing，Yang Yi，Qiu Haibo,Liu Ling
Department of Critical Care Medicine, Zhongda Hospital, Southeast University

2. Background and Aim
Mechanical ventilation may cause ventilator-induced diaphragmatic dysfunction (VIDD)
Mechanical ventilation induced diaphragmatic wasting atrophy is the most important mechanism of VIDD
miRNA is widely participated in regulation of muscular atrophy
To investigate the relationship between plasma miRNA and diaphragmatic function in mechanical ventilation patients

3. Method Screening of muscle specific miRNA
Included patients
the third days after operation
before extubation
one day before operation
Detection of plasma MyomiR level
Measurement of skeletal muscle thickness by Ultrasound
Measurement of diaphragmatic function by Ultrasound
Screening of muscle specific miRNA
Single-center prospective study
Undergoing scheduled cardiac surgery whose total time of controlled MV is greater than 12h and less than 48 h
Exclusion criteria: Severe respiratory central depression, can not placed EAdi catheter, pregnancy

4. Result miR-1 miR-133a miR-27a miR-29b miR-181a miR-206 miR-486
Patient characteristics
n = 40
Age, years
59.1±12.3
APACHE Ⅱ score
13.9±5.2
SOFA score
9.3±3.0
Total mechanical ventilation time (h)
26.1±2.3
Controlled mechanical ventilation time (h)
22.1±2.2
VT / IBW(ml/Kg)
6.1±1.6
PEEP（cmH2O）
5.6±1.3
FiO2(%)
42.5±4.9
Assisted mechanical ventilation time (h)
2.9±1.7
ICU hospital stay（d）
2.5±2.4
Type of operation CABG n(%)
20(50.0%)
Cardiac valve replacement n(%)
17(42.5%)
Operation duration (h)
5.1±1.4
Result
miR-1
miR-133a
miR-27a
miR-29b
miR-181a
miR-206
miR-486
→no significant change in the thickness of skeletal muscle
→level of plasma miR-1 and miR-206 was significantly low before extubation

5. Result- short time mechanical ventilation lead to decrease of diaphragmatic function decrease of plasma miR-206 level positively correlated with the decrease of diaphragm function
Note: compared with 1 days before operation, * P<0.05; compared with before extubation, # P<0.05

6. Conclusion
The decrease of plasma miR-206 level is positively correlated with the decrease of diaphragm function in mechanically ventilated patients
Thank you