Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT04103047 |
| Other study ID # |
262069 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
|
| First received |
|
| Last updated |
|
| Start date |
September 23, 2019 |
| Est. completion date |
December 18, 2020 |
Study information
| Verified date |
May 2021 |
| Source |
University Hospitals Coventry and Warwickshire NHS Trust |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Observational
|
Clinical Trial Summary
The aim of this study is to assess how the use of a breathing tube (Supraglottic Airway
Device) can affect the function of the jaw joint (Temporomandibular joint) movement. This
type of breathing tube is used for nearly 60% of general anaesthetics. To facilitate
insertion of this breathing tube, assisted mouth opening and forward movement of the jaw are
required.
These movements occur at the jaw joint (temporomandibular joint). In addition, for the
duration of the operation the mouth is kept slightly open by a breathing tube. There are a
few case reports in the literature suggesting minor effect on the jaw joint. Therefore, we
wish to study this further by evaluating the function of the jaw joint, 4 to 24 hours after
the operation.
Description:
1. INTRODUCTION 1.1 Background Supraglottic airway devices (SADs) are part of the mainstay
of anaesthetic practice, being the primary airway management device in 56% of general
anaesthetics. SADs are used by both novice and experienced anaesthetists, in addition to
anaesthetic practitioners, non-anaesthetic clinicians and other health care
professionals. They are routinely used to deliver anaesthetic gases and oxygen to the
patient during general anaesthesia. In an airway emergency, for example in the case of
failed intubation, a second-generation SAD has been recommended as a rescue device to
maintain oxygenation. This can also then be used as a conduit to intubate the trachea.
Although insertion of SADs considered to be relatively easy, it requires certain
manoeuvres. These include extension of the head and neck flexion, use of a jaw thrust
with adequate mouth opening, and then introduction of the device with a firm and gentle
motion down and backwards along the hard palate. These methods are thought to improve
the time to successful insertion of the SAD. Whilst movements such as these can be
viewed as simple and 'benign', investigators are concerned that these can cause
dysfunction of temporomandibular joint dysfunction in the postoperative period.
Most published research has been focused on insertion success and time taken to insert
the device. There has been limited research and literature about complications following
SAD insertion, such as gastric aspiration, trauma to or loss of the airway, and about
best insertion techniques, as mentioned above, including use of thermally softened SADs.
However, there are few reports of TMJ dysfunction and dislocation following SAD
insertion under general anaesthesia. This may be due in part to general anaesthesia
causing reduced muscle tone and greater joint mobility, but investigators assume a
degree of dysfunction is due to passive manipulation of the TMJ with forward movement of
the jaw and widened mouth opening for a prolonged period of time.
Some TMJ dysfunction may also be attributed to use of the SAD itself being in situ for a
prolonged period, where the cuff of the device occupies the oropharynx causing forward
displacement of the jaw. The recommended duration of SAD insertion ranges from one to
four hours.
1.2 Proposed study This study aims to evaluate the degree of TMJ dysfunction in the
postoperative period, in patients where a SAD has been used a primary airway device. The
study will be conducted at University Hospitals Coventry and Warwickshire National
Health Service (NHS) Trust and Birmingham Heartlands Hospital, part of the University
Hospital of Birmingham NHS Trust.
A member of the research team will approach eligible patients preoperatively to explain
the study, provide written information and obtain written consent. Consenting
participants will then be asked to complete a questionnaire and the member of the
research team will measure and record an airway assessment including jaw movements. Post
anaesthesia, participants will again be approached to complete a questionnaire and the
research team member will re-measure jaw movements. The preoperative responses and
measurements will be compared with those of postoperative responses and measurements.
1.3 Study population Those patients who undergo general anaesthesia for surgery, in whom
the SAD will be used as the primary airway device.
1.4 Treatment / Intervention (if applicable) The decision regarding the method of airway
management is decided by the patient's responsible anaesthetist, according to the
clinical indication. There is no additional treatment or intervention as a result of
this study, it is purely observational.
2. RATIONALE 2.1 Aims and hypothesis The aim of this study is to assess for an objective
difference between pre- and post-operative jaw movements following the use of SADs, and
to identify any subjective discomfort or perceived difference in TMJ function.
2.2 Justification
SADs are commonly used in anaesthetic and non-anaesthetic practice. SADs are placed by
clinicians of varying expertise, frequently using simple airway manoeuvres or the triple
airway manoeuvre to aid correct placement. Historically research has been carried out
regarding methods to aid correct SAD positioning and time to correct positioning, and also
regarding complications following the use of SADs as reported in 4th national audit project
of the Royal College of Anaesthetists and Difficult Airway Society. In recent years case
reports have been published concerning TMJ dislocation and dysfunction after the use of the
SAD.
are unaware of any studies investigating TMJ function after routine use of SAD under general
anaesthesia. If there is a significant deterioration in the function of TMJ during
postoperative period further guidance need to be devised on safe use of SADs. If there are no
differences, this will reassure the common and routine practice of use of SADs. If a
difference is found, it could lead to a change in education and improved clinical practice,
ultimately enhancing patient safety.
2.3 Assessment and management of risk This study is of patients' pre- and post-operative TMJ
function. Investigators will be approaching the patients in these periods to take part in
completing a short questionnaire, and also taking measurements of jaw movements. Patient
management will not be affected by the study. Investigators do not anticipate any additional
risks or benefits to the patient.
4. STUDY DESIGN This is a semi-qualitative questionnaire study of patients to assess TMJ
function after the airway has been secured with a SAD during general anaesthesia. The study
protocol will be discussed with the local research and development department and appropriate
Research Ethics Committee (REC) approval will be obtained.
Adult surgical patients who are due to undergo general anaesthesia and requiring SAD
insertion will be identified on the day of surgery. These patients will then be approached
and given patient information sheet. They will be given adequate time to read the information
sheet and any questions will be answered.
Consenting patients will be asked to complete a pre-operative questionnaire and jaw movements
(mouth opening = inter-incisor distance, jaw protrusion= the distance between the upper and
lower incisors when the lower jaw is fully protruded) and lateral jaw movements = right and
left lateral sliding of lower jaw = distance between upper and lower molars) will be measured
by one of the research team member. The above procedure will be repeated 4 to 24 hours in the
post-operative period using post-operative patient questionnaire and measurements of jaw
movements.
Sample size From our previous research on evaluating the correlation between airway
assessment parameters and depth of cricothyroid membrane, the observed mean for inter-incisor
distance (IID) was 45.5 mm with standard deviation 8.1. Investigators considered a reduction
in IID following used of SAD is clinically significant. Assuming a mean baseline IID of 35-
45 mm, with a pow-er of 90% power to detect a 10% reduction in IID with p<0.05, in total 120
patients were needed. Using G*Power 3.1.9.4 confirmed that a sample size of 120 using a
paired t-test with 2 tails will allow detection of significant. In total, 130 patients will
be recruited to overcome dropouts and incomplete data. Once screened, eligible patients will
be given information leaflets explaining the reason for the study, and any questions
answered. Following written consent, patients will be given a questionnaire to be completed
and jaw movements as described above will be measured.
7. TRIAL PROCEDURES The suitable patients for the study will be screened from the operating
theatre list. During the preoperative assessment one of the investigator or co-investigator
will provide patient information sheet. Patients will be given adequate time to read the
information and any questions will be answered. If they are satisfied and willing to take
part in the study, written consent will be obtained.
7.1 Recruitment Both Chief investigator and co-investigators identify the suitable operating
list. Then the suitable patients will be identified based on the scheduled surgical
procedure. Only those patients meeting the inclusion criteria will be approached.
7.1.1 Patient identification
The patients undergoing surgery that requires tracheal intubation are suitable to be included
in the study. Based on the scheduled surgery on the operating list, the suitable patients
will be identified. During the preoperative assessment one of the investigator or
co-investigator will provide patient information sheet. Patients will be given adequate time
to read the information and any questions will be answered. If they are satisfied and willing
to take part in the study, written consent will be obtained.
7.1.2 Payment There are no associated payments for participation in this study as no extra
expenses are expected to be incurred by the participants.
7.2 Consent Participants will be given enough time to read the patient information leaflet
(minimum of 2 hours). Once they have read the information, any questions will be answered. If
they agree for the study, they will be asked to complete the consent form. The consent will
be obtained by chief investigator, coinvestigator or one of the research team member,
supervised by one of the investigator.
7.3 Baseline data Base line data includes gender, age, weight, height, BMI & American Society
Anesthesiologist (ASA) score Airway assessment includes Mallampati score, thyromental
distance, mouth opening and neck movement
7.4 Trial assessments Visit one - prior to anaesthesia
Using the patient questionnaire, the following will be recorded:
- Patient mouth opening and pain at the temporomandibular joint
- Yes and no answers to questions regarding TMJ function
A member of the research team will then record:
- Mouth opening = inter-incisor distance
- Jaw protrusion= the distance between the upper and lower incisors when the lower jaw is
fully protruded
- Lateral jaw movements = right and left lateral sliding of lower jaw = distance between
upper and lower molars on lateral sliding
Visit two: 4-24 hours post operatively
Using the patient questionnaire, the following will be recorded:
- Patient mouth opening and pain at the temporomandibular joint
- Yes and no answers to questions regarding TMJ function
A member of the research team will then record:
- Mouth opening = inter-incisor distance
- Jaw protrusion= the distance between the upper and lower incisors when the lower jaw is
fully protruded
- Lateral jaw movements = right and left lateral sliding of lower jaw = distance between
upper and lower molars on lateral sliding
7.5 Long term follow-up assessments There is no long term follow-up for this study. The
participant will only be approached twice as described as above. Once pre-operatively and
once postoperatively.
8. STATISTICS
8.1 Sample size calculation From our previous research on evaluating the correlation between
airway assessment parameters and depth of cricothyroid membrane, the observed mean for
inter-incisor distance (IID) was 45.5 mm with standard deviation 8.1. A 10% reduction in IID
following use of SAD was considered to be clinically significant. Assuming a mean baseline
IID of 35- 45 mm, with a power of 90% power to detect a 10% reduction in IID with p<0.05, a
total of 120 patients are needed. Using G*Power 3.1.9.4 confirmed that a sample size of 120
using a paired t-test with 2 tails will allow detection of significant. Investigators aim to
recruit 130 patients to overcome drop outs and incomplete data. Once screened, eligible
patients will be given information leaflets explaining the reason for the study, and any
questions answered. Following written consent, patients will be given a questionnaire to be
completed and jaw movements as described above will be measured.
8.4 Participant population
All patients who are included in the study will be included in data analysis.
