Lower Esophageal Sphincter
Conditions
Keywords
Lower Esophageal Sphincter, Barrier pressure
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.
Interventions
DRUGalfentanil
20 mikrogr/kg
DRUGsaline
The amount of saline will be equal the amount (in ml) of the study-drug (alfentanil)in order to keep it blinded.
Sponsors
Region Örebro County
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 40 Years
Healthy volunteers
Yes
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.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in barrierpressure (in mmHg) in the area of the lower esophageal sphincter. | 1 min after the application of the induction agent (propofol) | Pressure variations in the lower esophageal sphincter will be measured continuously during the whole study. Registrations will be saved in the computer-software. Predetermined time points will be marked on the registrations for later evaluation. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Changes in barrierpressure (in mmHg) in the area of the lower esophageal sphincter. | during cricoidpressure application (continues for 15 sec) | Pressure variations in the lower esophageal sphincter will be measured continuously during the whole study. Registrations will be saved in the computer-software. Predetermined time points will be marked on the registrations for later evaluation. |
Countries
Sweden
Outcome results
None listed