Clinical Study Of Diaphragm Function In Septic Patients With Mechanical Ventilation By Ultrasound

Part Ⅰ: Primary Discussion for the Risk Factors that Affect Diaphragmatic Dysfunction with Mechanical VentilationObjective:Our aims were to explore the risk factors for diaphragmatic dysfunction on mechanically ventilated critically ill patients by ultrasound.Methods:80 cases of patients with mechanical ventilation were admitted in the ICU from March 2019 to June 2019.The diaphragm thickness,diaphragm thickening fraction and diaphragm movement were measured by ultrasound when the parameters of the ventilator were adjusted before patients were weaned.Ultrasound Measurements of thickness of the hemidiaphragm end-expiration（DTe）≤0.2cm,diaphragm thickening fraction（DTF）≤20%,diaphragm excursion（DE）≤1.5cm or diaphragmatic paradoxical movement were considered as diaphragmatic dysfunction（DD）,and patients were divided into diaphragmatic dysfunction group and normal diaphragm function group.At the same time,collect the basic clinical information of patients when they enter the department and analyze the risk factors that affect diaphragmatic dysfunction.Results:Compared with the normal diaphragm function group,patients in the diaphragm dysfunction group had longer mechanical ventilation treatment time（4.12±1.61day VS2.61±0.86 day）,procalcitonin was higher before mechanical ventilation（median 8.3pg/ml VS median 0.52pg/ml）,white blood cells High counts（median 15.4 10⁹/L VS median12.7 10⁹/L）,worsening hypoproteinemia（12.4±6.3g/L VS 29±7.1g/L）,rapid breathing rate（20±4/min VS 18±3/min）,and high shallow rapid breathing index（Median 46/min·L VS Median 40/min·L）,and whether muscle relaxants are used during hospitalization are risk factors for diaphragm dysfunction（P<0.05）.Multivariate logistic regression analysis showed that septic shock,respiratory rate before mechanical ventilation and mechanical ventilation duration were independent risk factors for diaphragmatic dysfunction in critical patients,with statistical significance（P<0.05）,and their risk ratios（OR）were0.265,0.620 and 0.250,respectively.Conclusion:During hospitalization in critical ICU patients,increased respiratory rate before intubation,combined with septic shock,and prolonged mechanical ventilation were independent risk factors for diaphragmatic dysfunction.Part Ⅱ: Observation and Study of Diaphragm Function in Sepsis Patients with Mechanical VentilationObjective:In this study,ultrasound examinations were carried out on mechanically ventilated critically ill patients every day to further observe the effect of severe sepsis on the patient’s diaphragm function,and the impact of the resulting results on the outcome of length of mechanical ventilation,length of stay in ICU and other outcomes.Methods:According to the inclusion and exclusion criteria,72 mechanically ventilated ICU patients from July 2019 to October 2020 were collected,including 35 patients with septic shock and 37 patients with non-septic shock.The thickness of the diaphragm was measured for the first time within 24 hours after the establishment of mechanical ventilation,and then the thickness of the diaphragm was measured every day until the patient was extubated,tracheotomy or death.The basic clinical information of the two groups was collected.Results:1.Comparison the basic conditions between the septic shock group and the nonseptic shock group,there was no statistical difference between the two groups in general information（age,gender,BMI,etc.）and respiratory support parameters（respiratory frequency,driving pressure,tidal volume in kilograms,etc.）;Compared with the nonseptic shock group,the septic shock group had higher infection indexes（PCT,CRP,etc.）,and the difference between the two groups was statistically significant（P<0.05）;The rate of diaphragm atrophy in septic shock group with early mechanical ventilation（within 4 days）was greater（0.28±0.11% VS 0.20±0.10%）,and the difference between the two groups was statistically significant（P<0.05）.Comparing the reintubation rate between the two groups,the septic shock group had a higher reintubation rate during hospitalization（20% VS 3%）,and the difference was statistically significant（P<0.05）;Comparing the mechanical ventilation time between the two groups,the median duration of mechanical ventilation in the septic shock group was higher（7 days VS 6 days）,and the difference was statistically significant（P<0.05）.2.Comparison between the septic shock group and the non-septic shock group in the early stage of mechanical ventilation: On the baseline T₀,there is no statistical difference in the DTe between the septic shock group and the non-septic shock group.On the first day of MV（T₁）,the difference in the DTe between the septic shock group（0.190±0.027cm）and the non-septic shock group（0.206±0.021cm）was statistically significant（P< 0.05）;On the second day of MV（T₂）,the difference in the DTe between the septic shock group（0.168±0.019cm）and the nonseptic shock group（0.188±0.017cm）was statistically significant,（P <0.05）;On the third day of MV（T₃）,the difference in the DTe between the septic shock group（0.159±0.021cm）and the non-septic shock group（0.179±0.014cm）was statistically significant（P <0.05）.For the comparison of daily DTe in the non-septic shock group,T₀ with day 1（T₁）,day 1（T₁）and day 2（T₂）,day 2（T₂）and day 3（T₃）,the difference in diaphragm thickness atrophy was statistically significant（P<0.05）.3.Compared with patients with a diaphragm atrophy rate ≤10%,the median time of mechanical ventilation（13 days VS 10 days）and the median time of ICU stay（16 days VS 12 days）in patients with a rate> 10% were prolonged,the difference was statistically significant（P <0.05）;Incidence of tracheotomy and mortality during hospitalization within two groups,the difference in rate was not statistically significant（P <0.05）.Conclusion : Both mechanically ventilated patients with severely infected and mechanically ventilated patients with（or without）mild infection led to atrophy of the diaphragm。That is,mechanical ventilation led to atrophy of the diaphragm,and patients with severe sepsis aggravated atrophy of the diaphragm.The degree of atrophy prolong the duration of mechanical ventilation and ICU stay in patients.