The Effect of an Opioid on the Lower Esophageal Sphincter During Anesthesia Induction

The Effect of Alfentanil on the Lower Esophageal Sphincter During Anesthesia Induction - a Study in Volunteers

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.

Study Overview

• Status: Completed
• Conditions: Lower Esophageal Sphincter
• Intervention / Treatment: Drug: alfentanil; Drug: saline

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.

• Study Type: Interventional
• Enrollment (Actual): 17
• Phase: Phase 4

Contacts and Locations

Study Locations

• Sweden
  • Örebro, Sweden, 21740
    • Örebro University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 38 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: opioid; Preoxygenation for 5 min. Injection of opioid (alfentanil 20 mikrogr/kg iv) after 2 min:Injection of induction drug(propofol 2-2.5mg/kg) after anesthesia induction: Application of cricoid pressure for 15 sec.	Drug: alfentanil; 20 mikrogr/kg; Other Names: alfentanil = rapifen
Placebo Comparator: placebo; Preoxygenation for 5 min. Injection of saline iv. after 2 min:Injection of induction drug(propofol 2-2.5mg/kg) after anesthesia induction: Application of cricoid pressure for 15 sec.	Drug: saline; The amount of saline will be equal the amount (in ml) of the study-drug (alfentanil)in order to keep it blinded.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in barrierpressure (in mmHg) in the area of the lower esophageal sphincter.	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.	1 min after the application of the induction agent (propofol)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in barrierpressure (in mmHg) in the area of the lower esophageal sphincter.	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.	during cricoidpressure application (continues for 15 sec)
Changes in barrierpressure (in mmHg) in the area of the lower esophageal sphincter.	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.	1min after the opioid/placebo injection

Collaborators and Investigators

• Sponsor: Region Örebro County
• Investigators: Principal Investigator: Magnus Wattwil, MD PhD, Department of Anesthesia and Intensive Care, Örebro University Hospital, Örebro,Sweden

Study record dates

Study Major Dates

• Study Start: September 1, 2010
• Primary Completion (Actual): October 1, 2010
• Study Completion (Actual): October 1, 2010

Study Registration Dates

• First Submitted: September 8, 2010
• First Submitted That Met QC Criteria: September 10, 2010
• First Posted (Estimate): September 13, 2010

Study Record Updates

• Last Update Posted (Estimate): November 9, 2016
• Last Update Submitted That Met QC Criteria: November 8, 2016
• Last Verified: September 1, 2010

More Information

Terms related to this study

• Keywords: Lower Esophageal Sphincter; Barrier pressure
• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Central Nervous System Depressants; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Anesthetics, Intravenous; Anesthetics, General; Anesthetics; Analgesics, Opioid; Narcotics; Alfentanil
• Other Study ID Numbers: EudraCT nr: 2010-020697-41

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: Yes
• IPD Plan Description: Original data can be available by contacting the principal investigator