A feasibility study of jaw thrust as an indicator assessing adequate depth of anesthesia for insertion of supraglottic airway device in morbidly obese patients / 中华医学杂志(英文版)

Background@#Jaw thrust has been proven as a useful test determining adequate depth of anesthesia for successful insertion of supraglottic airway device (SAD) in normal adults and children receiving intra-venous or inhalational anesthesia induction. This prospective observational study aimed to determine the feasibility and validity of this test when using as an indicator assessing adequate depth of anesthesia for successful insertion of SAD in spontaneously breathing morbidly obese patients receiving sevoflurane inhalational induction.@*Methods@#Thirty morbidly obese patients with a body mass index 40 to 73 kg/m2 undergoing bariatric surgery in Beijing Friendship Hospital from October 2018 to January 2019 were included in this study. After adequate pre-oxygenation, 5% sevoflurane was inhaled and inhalational concentration of sevoflurane was increased by 1% every 2 min. After motor responses to jaw thrust disappeared, a SAD was inserted and insertion conditions were graded. The anatomic position of SAD was assessed using a fiberoptic bronchoscope.@*Results@#The SAD was successfully inserted at the first attempt in all patients. Insertion conditions of SAD were excellent in nine patients (30%) and good in 21 patients (70%), respectively. The fiberoptic views of SAD position were adequate in 28 patients (93%).@*Conclusions@#Jaw thrust test is a reliable indicator determining adequate anesthesia depth of sevoflurane inhalational induction for successful insertion of SAD in spontaneously breathing morbidly obese patients.@*Clinical trial registration@#ChiCTR1800016868; http://www.chictr.org.cn/showproj.aspx?proj=28646.

Difficult laryngoscopy and tracheal intubation: observational study / Dificuldade na laringoscopia e na intubação orotraqueal: estudo observacional

Abstract Introduction: Since anesthesia complications associated with unexpected difficult airway are potentially catastrophic, they should be avoided. The modified Mallampati test and jaw-thrust maneuver enable the identification of difficult airway. The aim of this study was to associate the modified Mallampati test and the jaw-thrust maneuver with laryngoscopy (Cormack-Lehane) in an attempt to identify a better predictor of difficult airway in an adult population undergoing elective surgery. Method: A cross-sectional study in which 133 adult patients undergoing elective surgery requiring tracheal intubation were analyzed. The accuracy and specificity of the modified Mallampati test and jaw-thrust maneuver were assessed by correlating them with difficult laryngoscopy (Cormack-Lehane Degrees 3 and 4). Results: In the 133 patients evaluated the difficult intubation rate found was 0.8%; there was association between the two predictive tests proposed (p = 0.012). The values of 94.5% for specificity and 95.4% for accuracy were found for the jaw-thrust maneuver and for the modified Mallampati test, the values found were 81.1% and 81.2%, respectively. Kappa agreement identified a result of 0.240 between jaw-thrust maneuver and Cormack-Lehane, which was considered reasonable. On the other hand, a poor agreement (κ = 0.06) was seen between modified Mallampati test and Cormack-Lehane test. Conclusion: The jaw-thrust maneuver presented superior accuracy and agreement than the modified Mallampati test, showing the ability to identify a difficult airway. It is necessary to emphasize the association of tests in the evaluation of patients, emphasizing their complementarity to minimize the negative consequences of repeated laryngoscopies.

Resumo Introdução: As complicações anestésicas associadas às vias aéreas difíceis inesperadas por serem potencialmente catastróficas devem ser evitadas. O teste de Mallampati modificado e a manobra de protrusão mandibular possibilitam a identificação da via aérea difícil. O objetivo deste estudo foi associar o teste de Mallampati modificado e a manobra de protrusão mandibular com a laringoscopia (Cormack-Lehane) e tentar identificar um melhor preditor de via aérea difícil na população adulta submetida à cirurgia eletiva. Método: Estudo corte transversal, foram analisados 133 pacientes adultos submetidos a cirurgias eletivas que necessitavam de intubação orotraqueal. Avaliaram-se a acurácia e especificidade do teste de Mallampati modificado e da manobra de protrusão mandibular, correlacionados com laringoscopia difícil (Cormack-Lehane Graus 3 e 4). Resultados: Entre os 133 pacientes avaliados, a taxa de intubação difícil encontrada foi 0,8%, houve associação entre os dois testes preditores propostos (p = 0,012). Foram encontrados os seguintes valores para a especificidade 94,5% e a acurácia 95,4% na manobra de protrusão mandibular. Já para o teste de Mallampati modificado valores de 81,1% e de 81,2% respectivamente. A análise de concordância Kappa identificou entre manobra de protrusão mandibular e Cormarck-Lehane um resultado de 0,240; considerado razoável. Por outro lado, observou-se uma fraca (κ = 0,06) concordância entre o teste de Mallampati modificado e o Cormarck-Lehane. Conclusão: A manobra de protrusão mandibular apresentou acurácia e concordância superiores ao teste de Mallampati modificado, mostrou a capacidade de identificar uma via aérea difícil. Faz-se necessário enfatizar a associação dos testes na avaliação do paciente, destacar a complementariedade deles, minimizar as consequências negativas de laringoscopias repetidas.

Jaw-thrust induces sympathetic responses during induction of general anesthesia / 대한마취과학회지

BACKGROUND: Jaw-thrust is a noxious stimulus that might induce sympathetic responses. The purpose of this study, was to evaluate the effects of jaw-thrust on sympathetic responses. METHODS: We investigated seventy three patients. Patients who received general anesthesia were randomly divided into a control group (maintenance of combined airway maneuver with head tilt, open mouth by mouthpiece, and chin-lift, n = 30) and jaw-thrust group (maintenance of head tilt, open mouth and jaw-thrust, n = 30). In the jaw-thrust group, four minutes of endoscopy-guided force to the mandible to get the best laryngeal view were applied. For the control group, the combined airway maneuver was maintained during the same period. Arterial blood pressure (AP) and heart rate (HR) were recorded at predetermined time points (1 min before anesthesia induction, 2 min after fiberoptic bronchoscopy placement, and thereafter 1 min-interval during each airway maneuver) during jaw-thrust and chin-lift maneuver. The force amplitude applied for best laryngeal view during jaw-thrust was also measured. RESULTS: Peak systolic and diastolic AP increased 39.0 +/- 17.6 and 39.9 +/- 22.8 mmHg from the baseline (P 0.05). CONCLUSIONS: Performing the jaw-thrust maneuver induces significant sympathetic responses, irrespective of the force magnitude.

Comparison of the trapezius squeezing test and jaw thrust as indicators for laryngeal mask airway insertion in adults / 대한마취과학회지

BACKGROUND: The purpose of this study was to compare the effectiveness of the trapezius squeezing test with that of the jaw thrust maneuver as clinical indicators of adequate conditions for laryngeal mask airway (LMA) insertion in adults under sevoflurane anesthesia. METHODS: One hundred adult patients of ASA physical status 1 or 2 undergoing minor surgical procedures were randomly allocated to the T (trapezius squeezing, n = 50) group or the J (jaw thrust, n = 50) group. The LMA was inserted immediately after the loss of response to trapezius squeezing or jaw thrust. Successful and unsuccessful attempts were recorded. An unsuccessful attempt was defined as the occurrence of coughing, gagging, gross purposeful movements, breath-holding, laryngospasm, or an SpO2 < 90% during LMA insertion. Insertion time, end-tidal sevoflurane concentration, mean arterial pressure, and heart rate were recorded. RESULTS: The incidence of successful attempts was significantly higher in the T than in the J group (48/50 vs. 36/50, respectively). CONCLUSIONS: The trapezius squeezing test is a superior indicator of an adequate condition for LMA insertion compared to the jaw thrust maneuver in adults under sevoflurane anesthesia.

Transient facial nerve palsy after general anesthesia: A case report / 대한마취과학회지

A 44-year-old woman underwent a breast cancer operation under general anesthesia. We performed bronchoscope guided intubation along with a jaw thrust maneuver on the patient to achieve a good visual field. The patient complained of left lower lip weakness after the operation. The lower lip of the patient was deviated to the right. The cause might have been a temporary compression of the left facial nerve at the mandibular angle during performance of the jaw thrust maneuver. Fortunately, the patient's palsy recovered completely during the following one month. We report here on a case of transient facial nerve palsy after general anesthesia, and this occurred despite performing a very short duration of jaw thrust.