The Optimal Time to Put Laryngeal Mask Airway in the Mouth Under General Anesthesia (LMA)

• ClinicalTrials.gov Identifier: NCT00972491
• Recruitment Status: Completed
• First Posted: September 7, 2009
• Last Update Posted: December 4, 2013
• Sponsor: Tufts Medical Center
• Information provided by (Responsible Party): Tufts Medical Center

Study Description

Brief Summary:

Laryngeal mask airway (LMA) is routinely used for some patients who have surgery under general anesthesia. LMA is placed in the mouth and allow the anesthesia to be given without having to put a breathing tube in the throat. Previous studies have focused on the effect of different anesthesia medicines on optimal condition for LMA use. The objective of the present study is to find the optimal time for LMA insertion.

Condition or disease	Intervention/treatment	Phase
General Anesthesia	Procedure: Insertion of Laryngeal Mask Airway	Not Applicable

Detailed Description:

This is a randomized, controlled, blinded trial. Midazolam, 2 mg and fentanyl 1.0 µg/kg, would be given prior to induction with propofol, 2.5 mg/kg.

The investigator who does the induction of general anesthesia will also be responsible for the timekeeping. For this reason, it is not possible for this investigator to be blinded to randomization. The induction would conclude after loss of eyelash reflex (LER). At that point insertion of the LMA (#4 for females, #5 for males) will occur 0, 60 and 90 seconds after LER. The LMA will be lubricated with a water soluble gel and will be inserted with a deflated cuff according to the technique described by Brain.

The investigator who inserts the LMA (Inv1) will be in the operating room and blinded to randomization groups by not seeing the induction of general anesthesia. This investigator will insert the LMA only when called by the investigator who induces general anesthesia (Inv2). Inv1 will also grade ease of LMA insertion.

The primary outcome is Jaw opening at the time of LMA insertion, defined as full 1, partial 2, and nil 3.

Secondary outcomes include:

1. Insertion of LMA (easy, difficult, impossible)
2. Coughing or gagging (none, some, significant)
3. Head or body movement (none, some, significant)
4. Laryngospasm or airway obstruction (none, partial, total)

Study Design

• Study Type: Interventional (Clinical Trial)
• Actual Enrollment: 198 participants
• Allocation: Randomized
• Intervention Model: Parallel Assignment
• Masking: Single (Outcomes Assessor)
• Primary Purpose: Treatment
• Official Title: The Optimal Time of Insertion of Laryngeal Mask Airway With Propofol Induction
• Study Start Date: September 2009
• Actual Primary Completion Date: December 2013
• Actual Study Completion Date: December 2013

Arms and Interventions

Arm	Intervention/treatment
0 sec, 60 sec, 90 sec; LMA will be inserted at 0, 60, and 90 seconds after eyelash reflex disappears	Procedure: Insertion of Laryngeal Mask Airway; The LMA will be inserted at 0 sec, 60 sec. and 90 sec. after induction of general anesthesia; Other Name: Laryngeal Mask Airway

Outcome Measures

Primary Outcome Measures :

1. Ease of Mouth opening [ Time Frame: From Induction of general anesthesia to satisfactory LMA insertion ]

Eligibility Criteria

• Ages Eligible for Study: 18 Years to 65 Years (Adult, Older Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: No

Criteria

Inclusion Criteria:

• subjects 18 years or older
• ASA status 1-3

Exclusion Criteria:

• high risk of aspiration
• anticipated difficult airway
• use of sedative drugs
• patient refusal

Contacts and Locations

Locations

United States, Massachusetts

Tufts Medical Center

Boston, Massachusetts, United States, 02111

Sponsors and Collaborators

Tufts Medical Center

Investigators

• Principal Investigator: Pei-shan Zhao, MD,PhD; Tufts Medical Center

More Information

• Responsible Party: Tufts Medical Center
• ClinicalTrials.gov Identifier: NCT00972491
• Other Study ID Numbers: IRB-8910
• First Posted: September 7, 2009
• Last Update Posted: December 4, 2013
• Last Verified: December 2013