Effects of Remifentanil on Respiratory Function in Mechanically Ventilated Patients

Study Overview
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Brief Summary
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Sedation is widely used in mechanically ventilated patients. Propofol, benzodiazepines and opioids are the most used drugs. The study hypothesis is that sedation with remifentanil (an opioid drug) could improved respiratory pattern and effort in mechanically ventilated patients with rapid shallow breathing or high respiratory rate.

Official Title
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Effects of Remifentanil on Breathing Pattern, Respiratory Effort and Gas Exchange in Mechanically Ventilated Patients.

Conditions
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Respiratory Insufficiency, Respiration, Artificial, Conscious Sedation

Intervention / Treatment
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* Drug: remifentanil
* Drug: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: pressure support ventilation or CPAP respiratory rate > 35.min-1 respiratory rate/tidal volume > 105 Exclusion Criteria: vasoactive agents (dopamine lower than 5 mcg.kg-1.min-1 is not considered as vasoactive agent) body temperature > 38 °C Glasgow Coma Scale < 9 FIO2 > 0.6 PEEP > 10 cmH2O pH < 7.30

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: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: treatment<br>Any patient alternatively receive both remifentanil and isotonic saline (placebo)infusion. The order of infusion is randomized. An interval of 30 minutes is planned between the two infusions. | Drug: remifentanil<br>* 0.05 mcg.kg-1.min-1 for 30 minutes by continuous endovenous infusion<br>Drug: placebo<br>* NaCl 0.9 %<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| respiratory rate/tidal volume |  | before and after remifentanil infusion; before and after placebo infusion. | 
| pressure-time product |  | before and after remifentanil infusion; before and after placebo infusion. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| double product of respiratory system |  | before and after remifentanil infusion; before and after placebo infusion. | 
| dynamic intrinsic PEEP |  | before and after remifentanil infusion; before and after placebo infusion. | 
| adverse events |  | during all the study period | 
| arterial pH |  | before and after remifentanil infusion; before and after placebo infusion. | 
| level of sedation (RASS) |  | before and after remifentanil infusion; before and after placebo infusion. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Respiratory Insufficiency, Respiration, Artificial, Remifentanil, Respiratory Mechanics, Work of Breathing