Effects of Standing at Different Angles on Transpulmonary Pressure

Study Overview
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Brief Summary
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Effects of standing at different angles on transpulmonary pressure

Detailed Description
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Objective: To study the effect of different standing angles on cross-lung pressure.Background: Long-term bed rest in ICU patients leads to upward movement of diaphragm and increased intrathoracic pressure in mechanically ventilated patients, resulting in lower cross-lung pressure. If the end-expiratory cross-lung pressure is negative, lung tissue compression and atelectasis will occur.Standing can lower the diaphragm, improve the pressure across the lungs, and improve ventilation.Selection methods: patients with invasive mechanical ventilation in the ICU, on the premise of stable hemodynamics, with the aid of electric bed training in standing in different angles, start from 20 degrees, 5 degrees up every five minutes, the largest up to 80 degrees, each Angle across the pulmonary pressure, die cavity ratio, tidal volume and breathe out carbon dioxide at the end of the record, and record whether low blood pressure, an accident in the process of take off the tube and other adverse reactions.

Official Title
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Effects of Standing at Different Angles on Transpulmonary Pressure

Conditions
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Pulmonary Disease

Intervention / Treatment
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* Behavioral: Change of standing Angle


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The age is ≥ 18 years old; the hemodynamics is stable; 50 < heart rate < 120 beats / min ; 90 < systolic blood pressure < 200mmHg ; 55 < mean arterial pressure < 120mmHg; do not increase the dose of pressor drugs for at least 2 hours; intracranial pressure is stable and there are no seizures within 24 hours; the respiratory state is stable; the patient's finger pulse oxygen saturation ≥ 88%; 10 < respiratory frequency < 35 beats / min. Exclusion Criteria: Pregnancy; acute cardio-cerebrovascular events; spinal or limb fractures; active bleeding.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 95 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Standing Angle<br>Assist the electric hospital bed to conduct different Angle standing training, starting from 20 degrees, every five minutes to rise 5 degrees, the maximum rise to 80 degrees | Behavioral: Change of standing Angle<br>* Change the patient's standing Angle by using an electric bed<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| transpulmonary pressure | End-expiratory pressure across the lungs is recommended at 0-5cmH2O. | 5 minutes | 
| Esophageal pressure | The change in esophageal pressure represents the degree of inspiratory effort.The greater the variation, the harder the inhale. | 5 minutes | 
| Dead space rate | the smaller，the better | 5 minutes | 
| tidal volume | Standard tidal volume: standard weight based on height, 6 to 8ml per kg body weight | 5 minutes | 
| partial pressure of carbon dioxide in endexpiratory gas | The smaller the difference between pCO2 and arterial blood gas, the better | 5 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| adverse reaction | hypotension、Accident to take off the tube、Drop of bed，Record the number of times it happens.The more it happens, the less safe it is. | an hour |