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Trapezius squeeze test as an indicator for depth of anesthesia for laryngeal mask airway insertion in children
Sarla Hooda1, Kiranpreet Kaur, Kamal N Rattan
1Department of Anaesthesiology and Critical Care, Pt. B.D. Sharma PGIMS, Rohtak, India.
Insights
The Trapezius Squeeze Test (TST) reliably indicates optimal anesthesia depth for laryngeal mask airway (LMA) insertion in children. A negative TST ensures successful LMA placement with excellent conditions.
Area of Science:
- Anesthesiology
- Pediatric Anesthesia
- Airway Management
Background:
- Clinical tests assess anesthesia depth, including the Trapezius Squeeze Test (TST).
- TST involves squeezing the trapezius muscle to evaluate patient response.
- This test is a simple method to gauge anesthetic depth.
Purpose of the Study:
- To evaluate the negative Trapezius Squeeze Test (TST) as an indicator for optimal anesthesia depth.
- To assess the efficacy of TST for laryngeal mask airway (LMA) insertion in pediatric patients.
- To determine the reliability of TST in spontaneously breathing anesthetized children.
Main Methods:
- One hundred pediatric patients aged 3-5 years undergoing elective surgery were studied.
- Anesthesia was induced with sevoflurane and oxygen.
- TST was performed every 15 seconds until negative, followed by LMA insertion.
Main Results:
- The mean time for TST to become negative was 271.80 ± 55.8 seconds.
- LMA insertion was successful on the first attempt in 96% of patients.
- Excellent or acceptable insertion conditions were reported in all patients.
Conclusions:
- A negative TST is a dependable indicator for LMA placement in spontaneously breathing children.
- Optimal conditions for LMA insertion are achieved when TST is negative.
- This method provides excellent conditions for LMA placement without adverse effects.
Background:
Clinical tests, such as loss of verbal contact, eyelash reflex, corneal reflex, and jaw relaxation, are used to assess the depth of anesthesia. "Trapezius squeeze test" (TST) is one such clinical test. It is a simple test to perform in which 1-2 inches of trapezius muscle is held and squeezed in full thickness and response is evaluated in the form of toe/body movement.
Materials And Methods:
One hundred pediatric patients between 3 and 5 years of age, scheduled to undergo elective surgery, were included in this study. We evaluated negative TST as an indicator for optimal anesthesia depth for laryngeal mask airway (LMA) insertion in anesthetized spontaneously breathing children. Anesthesia was induced using 4% sevoflurane in oxygen. As the child lost the verbal contact or loss of body movement, TST was performed. Test was repeated every 15 s till it became negative. When the TST became negative, a well lubricated, appropriate-size LMA was inserted.
Results:
Mean time for TST to become negative in our study was 271.80 ± 55.8 s and ease of insertion was excellent in 91 patients and acceptable in 9 patients. LMA was successfully inserted in first attempt in 96% patients.
Conclusions:
Negative TST is a reliable indicator for placement of LMA in spontaneously breathing children. Excellent conditions for LMA placement are present in majority of the patients without any untoward effects at this point of time.
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