Clinical trial NCT01199458: The Effect of an Opioid on the Lower Esophageal Sphincter During Anesthesia Induction
Official title: The Effect of Alfentanil on the Lower Esophageal Sphincter During Anesthesia Induction - a Study in Volunteers
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Lower Esophageal Sphincter
Keywords: Lower Esophageal Sphincter
Barrier pressure
Lead sponsor: Region Örebro County
Sponsor class: OTHER
First posted: 2010-09-13
Enrollment: 17
Sex: ALL
Minimum age (years): 18
Maximum age (years): 40
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: PREVENTION

Brief summary: This study evaluates the effects of adding an opioid (alfentanil) during anesthesia induction with respect to the barrierpressure in the esophagogastric junction.

The secondary aim was to investigate whether the effect of cricoid pressure influences the barrierpressure.

Detailed description: During anesthesia induction and tracheal intubation one major concern is to avoid passive regurgitation of gastric content and aspiration.

The lower esophageal sphincter is a muscle located at the distal end of the esophagus. It plays an important role in creating a barrier between the stomach and the esophagus. The term "barrierpressure" is defined as the pressure difference between the lower esophageal sphincter pressure and the pressure in the stomach (intragastric pressure).

There are studies showing that opioids given iv/im, in the vein or in the muscle, may decrease the pressure in the lower esophageal sphincter and hereby increase the risk of aspiration.

Nevertheless,other studies shows that opioids are still frequently given to patients during anesthesia induction. This is done in order to prevent the cardiovascular response to (the painful) intubation which can often be seen as an equally high risk for the patient as the risk of aspiration.

In light of the above description, the investigators are planning a study in volunteers with the primary aim of investigating the effects of an opioid (alfentanil) on the pressures in the lower esophageal sphincter.

Another safety measure taken during anesthesia induction is the so called "cricoid pressure". This is based on the theory that passive regurgitation of gastric content may be prevented by occluding the esophagus by pressing on the cricoid cartilage. However, there are studies indicating that the application of cricoid pressure also may decrease the tonus of the lower esophageal sphincter.

The secondary aim of the study is to investigate the effect of cricoid pressure application on the pressure in the lower esophageal sphincter.

Measurements are being done using high-resolution solid-state manometry.

Eligibility criteria: Inclusion Criteria:

* Healthy volunteer 18-40 years old
* Informed,signed and dated consent

Exclusion Criteria:

* Pharyngoesophageal dysfunction
* Gastro/intestinal-,cardiovascular-,lung- or neurologic disease
* Ongoing medication
* Allergy to alfentanil, propofol, soya or peanuts
* Pregnancy or breast-feeding
* BMI\>30
* Participation in other clinical trial -ongoing or during last 30 days.

Primary outcomes:
measure: Changes in barrierpressure (in mmHg) in the area of the lower esophageal sphincter.
timeFrame: 1 min after the application of the induction agent (propofol)
Secondary outcomes:
measure: Changes in barrierpressure (in mmHg) in the area of the lower esophageal sphincter.
timeFrame: during cricoidpressure application (continues for 15 sec)
measure: Changes in barrierpressure (in mmHg) in the area of the lower esophageal sphincter.
timeFrame: 1min after the opioid/placebo injection
Other outcomes:
Locations:
city: Örebro
country: Sweden
facility: Örebro University
Study officials:
affiliation: Department of Anesthesia and Intensive Care, Örebro University Hospital, Örebro,Sweden
name: Magnus Wattwil, MD PhD
role: PRINCIPAL_INVESTIGATOR
References: