Inhalational Sedation and Mechanical Power

Study Overview
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Brief Summary
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Analgosedation is usually given to critically ill patients admitted in ICU. Fentanyl is the most common agent used for this purpose. For sedative agent, midazolam and propofol are commonly administered. However, too much sedation is apparently associated with increased duration of mechanical ventilation, prolonged ICU stay, and increased mortality. In mechanically ventilated patients, mechanical power is the respiratory mechanic that can predict clinical outcomes including mortality in both ARDS and non-ARDS patients. Previous study demonstrated that sedating mechanically ventilated patients with propofol could decreased mechanical power. This was possibly associated with improved clinical outcomes in these patients. At present, there is no clinical study investigating effects of inhalation sedation on mechanical power and clinical outcomes in mechanically ventilated patients.

Detailed Description
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In the intensive care unit (ICU), sedation is used to improve comfort and tolerance during mechanical ventilation, invasive diagnostic and therapeutic interventions or nursing care. The most commonly used sedatives are intravenous benzodiazepines and propofol. These agents are associated with over-sedation in 40 to 60% of patients, which can lead to prolonged intubation, delirium and drug-induced hypotension. Volatile anesthetics are increasingly used for sedation in European and Canadian intensive care units that offer advantages of rapid drug on and off effects and clearance via pulmonary exhalation with no active metabolites. Delivery of volatile agents in the ICU can be simply performed using a small lightweight and portable anesthetic reflector so-called anesthesia conserving device. Compared with intravenous sedatives, volatile anesthetics may allow shorter time to extubation and can facilitate mental recovery. In mechanically ventilated patients, a growing body of evidence suggests that the mechanical power (MP) plays an important role in the ventilator-induce lung injury (VILI) and prognosis in in both acute respiratory distress syndrome (ARDS) and non-ARDS patients. MP is the energy per unit time released to the respiratory system according to the tidal volume, PEEP, respiratory rate, and flow applied. In ARDS patients receiving invasive mechanical ventilation, high MP was associated an increased mortality. Moderate to deep sedation can inhibit the respiratory center and reduces the excessive respiratory drive, thereby reducing transpulmonary pressure and MP as well as probably reducing lung injury. The purpose of this study aims to investigate the effect of inhalation sedation on MP in mechanically ventilated patient admitted in the ICU. We hypothesize that MP in mechanically ventilated patients can be reduced by administering inhalational sedation.

Official Title
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Effect of Inhalational Sedation on Mechanical Power in Mechanically Ventilated Patients: a Pilot Open-label Randomized Controlled Study

Conditions
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ICU, Mechanical Ventilation, Sedation, Mechanical Power, Lung Injury

Intervention / Treatment
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* Drug: Inhalational sedation
* Drug: Convention sedation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patient with age >18 years old; and Patient who is admitted to the participating ICU; and Patient who receives respiratory support with invasive mechanical ventilation via endotracheal tube < 12 hours prior to inclusion with anticipated duration of > 48 hours Exclusion Criteria: Patient with history or suspected history of malignant hyperthermia Patient with evident or suspected increased intracranial pressure Patient with high severity of illness whose ICU survival is not expected Patient who refuses or patient whose proxy refuses to participate in the study

Ages Eligible for Study
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Minimum Age: 18 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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Conventional sedation<br>Conventional sedation receiving analgosedation with fentanyl | Drug: Convention sedation<br>* Conventional sedation receiving analgosedation with fentanyl<br>|
| Experimental: Inhalational sedation<br>Inhalational sedation receiving isoflurane for sedation for 12 hours | Drug: Inhalational sedation<br>* Inhalational sedation with isoflurane for 12 hours<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in mechanical power | Change in mechanical power from Phase 1 to Phase 2 compared between 2 groups | At 15 hours after intervention applied | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in oxygenation | Change in oxygenation from Phase 1 to Phase 2 compared between 2 groups | At 15 hours after intervention applied | 
| Change in respiratory mechanic | Change in respiratory mechanic from Phase 1 to Phase 2 compared between 2 groups | At 15 hours after intervention applied | 
| Change in serum interleukin 6 | Change in serum interleukin 6 from Phase 1 to Phase 2 compared between 2 groups | At 15 hours after intervention applied | 
| Change in serum C-reactive protein | Change in serum C-reactive protein from Phase 1 to Phase 2 compared between 2 groups | At 15 hours after intervention applied |