Using temporomandibular joint mobility to predict difficult tracheal intubation

Relationship between difficult tracheal intubation and obstructive sleep apnoea

Comparison of the Upper Lip Bite Test with Measurement of Thyromental Distance for Prediction of Difficult Intubations

IntroductionDifficult laryngoscopy and intubation are serious problems among critically ill patients in emergency department (ED) so utility of a rapid, accurate and noninvasive method for predicting of these patients are necessary. Ultrasonography has been recently used in this regard and this study was conducted to investigate the correlation of some introduced upper airway ultrasound parameters with difficult laryngoscopy / difficult intubation in patients referred to the ED.MethodIn this prospective observational study all patients ≥ 18-year-old who had an indication for rapid sequence intubation (RSI) were included. Ultrasound parameters including Hyoid Bone Visibility (HBV), Distance from Skin to Hyoid Bone (DSHB), Distance from Skin to Vocal Cords (DSVC), Distance from Skin to Thyroid Isthmus (DSTI), and Distance between Arytenoids Cartilages (DBAC) were measured in all cases. The patients underwent RSI and thereafter the patients’ baseline characteristics, Cormack-Lehane grade, number of attempted laryngoscopy were recorded in a pre-prepared check list and compared with measured ultrasound parameters. The “difficult laryngoscopy” was defined as Cormack-Lehane classification grades III/IV; and need for more than 3 intubation attempts was considered as “difficult intubation”.ResultsOne hundred and twenty-three patients (52% male) were included of whom 10 patients (8.1%) were categorized as difficult laryngoscopy cases; and just 4 (3.3%) cases underwent more than 3 laryngoscopy attempts who considered as difficult intubation cases. The mean age of the patients in non-difficult and difficult intubation groups were 69.2 ± 15.16 and 68.77 ± 17.37 years, respectively (p > 0.05). There was no significant relationship between difficult laryngoscopy and HBV (p = 0.381) but has significant correlation with difficult intubation (p = 0.004). The DSHB had a significant correlation with difficult laryngoscopy (p = 0.002) but its correlation with difficult intubation was not significant (p = 0.629). The DSVC and DSTI had a significant relationship with both difficult laryngoscopy (p = 0.003 and p = 0.001), and difficult intubation (p = 0.025 and p = 0.001). The DBAC had not significant correlation neither with the difficult laryngoscopy (p = 0.142), nor with difficult intubation (p = 0.526).ConclusionThe findings showed that ultrasound parameters including soft tissue DSHB, DSVC and DSTI could be proper predictors of difficult laryngoscopy. Also, HBV, DSVC and DSTI may be proper predictors for difficult intubation. But DBAC was not useful in this regard.

BackgroundPostoperative retropharyngeal hematoma (RH) is a potentially life-threatening complication of anterior cervical spine surgery (ACSS). Difficult intubation frequently arises during airway management in patients with RH, presenting substantial challenges in clinical practice. This retrospective cohort study aimed to (1) identify risk factors linked to RH development after ACSS, and (2) highlight risk factors for difficult intubation within the RH patient group.MethodsThis retrospective analysis utilized a single-center longitudinal ACSS cohort from March 2013 to March 2024. The RH cohort was defined as patients who developed postoperative RH, while a non-RH control group (4:1 ratio) was established through matching for the same operator, gender, and operative year, with age matched within ± 5 years. Patients with RH were categorized into two groups based on whether they experienced difficulty in tracheal intubation during airway management prior to hematoma evacuation: the difficult intubation group and the non-difficult intubation group. Multivariable analysis identified independent risk factors for RH and difficult intubation.ResultsThe incidence of postoperative RH following ACSS was 0.25% (42/16,624). Among these RH cases, 15 patients experienced difficult intubation during airway management. Multivariable logistic regression demonstrated markedly elevated odds of RH formation with increasing systolic blood pressure difference between extubation and wound closure (ΔSBP Ext-Closure): 30–50 mmHg yielded an adjusted OR of 3.30 (95% CI: 1.34–8.16, P = 0.010) vs. the < 30 mmHg reference, while > 50 mmHg showed an OR of 13.16 (95% CI: 4.93–35.10, P < 0.001).​ Additionally, Grade III/IV acute airway obstruction (AAO) (OR, 5.365; 95%CI, 11.089–26.445; P = 0.011) and longer time interval from onset to airway intervention (OR, 2.262; 95% CI, 1.208–4.236; P = 0.039) were identified as independent risk factors for difficult intubation.ConclusionsAn elevated ΔSBP Ext-Closure ​may be independently associated with​ an increased risk of RH following ACSS. Among RH patients, Grade III/IV AAO and longer time interval from onset to airway intervention ​correlated with​ higher rates of difficult intubation. Close monitoring and tailored management may benefit high-risk cohorts​.

Aim: Difficult tracheal intubation is a fundamental cause of perioperative morbidity and mortality. The frequency of difficult intubation is thought to be higher in the pediatric age group due to the different anatomical and physiological structures, and it may not be easy to detect this beforehand. Anthropometric measurements were evaluated before the elective operation and the relationship of some parameters with difficult intubation. Material and Method: This prospective cross-sectional study was conducted on 90 pediatric patients aged 2-14 who underwent elective surgery under general anesthesia. All patients’ age, gender, height, weight, body surface area (BSA), and body mass index (BMI) records were recorded before the operation. Mallampati scoring, head and neck circumference, thyromental distance measurements, and head circumference/neck circumference ratio were performed. Cormack-Lehane (CL) scoring and endotracheal intubation were applied during direct laryngoscopy of the operated patients. Children with easy intubation (CL grade 1 and 2) group 1; children who underwent difficult intubation (CL grade 3 and 4) were defined as group 2. Results: There was no significant relationship between Groups I and II in terms of age, height and weight values. There was no significant relationship between the two groups with BSA and thyromental distance measurements. Mallampati scores were found to be grades 3 and 4 (3.3%) in three of the 90 patients, and CL scores of 3 and 4 (4.4%) in four patients. A significant correlation was found between Mallampati scoring and CL scoring. A statistically significant difference was found between the two groups regarding head/neck ratios and BMI. Conclusion: In our study, head circumference/neck circumference ratio and BMI were found to be helpful while predicting difficult intubation in children with normal physical characteristics, 2-14 years of age, who underwent elective surgery. Our findings can be supported by further studies that will be planned and include more patients.

Objective: To determine a clinically useful variable for predicting difficult tracheal intubation in patients with seemingly normal airways. Material and Methods: In our study we had included 68 patients from September 2011 to September 2013 who needed tracheal intubation for elective maxillofacial surgery. An airway assessment test was conducted on each patient prior to general anaesthesia, with respect to mouth opening, sternomental distance, thyromental distance, oropharyngeal (Mallampati) classification and ability to protrude the mandible. After induction of anaesthesia, the laryngeal view during laryngoscopy was graded and then the ability to intubate was assessed. Results: Incidence of difficult intubation occurred in 8 (11.76%) cases out of 68 patients. Airway test that was significant for predicting difficult tracheal intubation was SMD of less than 12.5 cm, TMD of less than 6 cm, a score according to Mallampati et al. of greater than III, protrusion of mandible position B and position C and IIG less than 3 cm with sensitivity of 87.5%, 62.5%, 62.5%, 25% and 50%, respectively. Conclusion: Our study concluded that sternomental distance had the highest sensitivity of 87.5% which was statistically significant (p

BackgroundArthrocentesis of the temporomandibular joint (TMJ) is an easy, highly efficient, minimally invasive procedure for treating temporomandibular joint disorders (TMDs). However, in some cases of mouth opening limitation (MOL), routine arthrocentesis is ineffective due to severe fibrotic adhesion in the superior joint space of the TMJ. In this condition, mechanical lysis of the adhesions might be needed to resolve the MOL, as well as other symptoms, such as chronic pain. Currently, this can be achieved by arthroscopic surgery or open TMJ surgery. The objective of this study was to introduce and evaluate our trial of the adhesion lysis procedure during arthrocentesis of the TMJ using normal 18-gauge needles.ResultsIn this study, 40 patients with MOL due to disc derangement underwent conventional arthrocentesis at first and then physical detachment was conducted using the same needle. The change in maximum mouth opening (MMO) and the pain at the TMJ were recorded before, during, and after treatment according to our protocol. The mean increase in MMO after conventional arthrocentesis was 6.6 ± 4.2mm. The mean increase in MMO after the detachment procedure with the same needle was 4.2 ± 2.0 mm. The MMO in ten patients was significantly increased after the detachment procedure than after arthrocentesis alone. In all cases, the pain intensity in the TMJ significantly decreased over time, whereas the MMO increased over time. No adverse effect was observed in all joints during our observation periods.ConclusionWe confirmed that our simple lysis procedure with the same needle of the arthrocentesis of the TMJ could not only improve the MMO more than after a conventional arthrocentesis but also resolve severe adhesion of the joint space that was ineffective by conventional arthrocentesis. Although this additional lysis procedure is simple, it might reduce the number of cases of more invasive procedures such as arthroscopic surgery or open TMJ surgery.

Background and objective The primary responsibility of the anesthesiologist is to provide adequate oxygenation and ventilation to the patient by securing the airway. Prediction of Cormack-Lehane (CL) grading preoperatively helps patients' airway management during anesthesia induction, particularly in difficult intubations. Our study aims to evaluate airway assessment modalities using ultrasound and conventional clinical screening methods for predicting difficult laryngoscopy and intubation. Materials and methods This prospective observational study was conducted on 100 patients aged between 18 and 70 years belonging toASA classes I, II, and IIIscheduled for elective surgery requiring general anesthesia under endotracheal intubation was included in the study. Patients who needed rapid sequence induction and had a history of difficult intubation, obese patients with a body mass index (BMI) of more than 40, patients with notable swelling in the neck region (thyroid), pregnant patients, and patients with maxillofacial anomalies were excluded from the study. Clinical parameters such asbody mass index, neck circumference, modified Mallampatigrading, thyromental distance, and ultrasound parameters such as anterior neck soft tissue thickness at the level of the thyrohyoid membrane (ANS-TM) and anterior neck soft tissue thickness at the level of vocal cord (ANS-VC) were obtained preoperatively. After intubation, the CL grading was noted and categorized into two groups: easy (classes 1 and 2) and difficult (classes 3 and 4). Descriptive statistics included frequency and percentage for categorical variables and mean±standard deviation for continuous variables. The chi-square test was applied to find the relationship between easy and difficult laryngoscopy when compared with the outcome for categorical variables. A P value of less than 0.05 was considered significant throughout the study. The receiver operating characteristics curve (ROC curve) was used to determine the sensitivity and specificity to predict the outcomes. Results Ultrasound-guided measurements of ANS-TM and ANS-VC are independent predictors of difficult laryngoscopy compared with clinical screening tests. Of the two parameters, we found that ANS-TM has a better diagnostic value for predicting a difficult airway with an area under the ROCcurve (AUC) of 91% compared with ANS-VC, which has an AUC of 84%. Of the clinical parameters, the modified Mallampati grading has an AUC of 81%, leading to better diagnostic value in the prediction of a difficult airway. Conclusion Our study demonstrated that ANS-TM and ANS-VC are independent predictors of a difficult airway. ANS-TM has a better correlation with CL grading. Clinical screening tests should be combined with ultrasound measurements to aid in the better prediction of difficult laryngoscopy.

Evidence-based clinical diagnostic criteria for temporomandibular joint (TMJ) arthritis are not available. To establish (i) criteria for clinical diagnosis of TMJ arthritis and (ii) clinical variables useful to determine inflammatory activity in TMJ arthritis using synovial fluid levels of inflammatory mediators as the reference standard. A calibrated examiner assessed TMJ pain, function, noise and occlusal changes in 219 TMJs (141 patients, 15 healthy individuals). TMJ synovial fluid samples were obtained with a push-pull technique using the hydroxycobalamin method and analysed for TNF, TNFsRII, IL-1β, IL-1ra, IL-1sRII, IL-6 and serotonin. If any inflammatory mediator concentration exceeded normal, the TMJ was considered as arthritic. In the patient group, 71% of the joints were arthritic. Of those, 93% were painful. About 66% of the non-arthritic TMJs were painful to some degree. Intensity of TMJ resting pain and TMJ maximum opening pain, number of jaw movements causing TMJ pain and laterotrusive movement to the contralateral side significantly explained presence of arthritis (AUC 0.72, P<.001). Based on these findings, criteria for possible, probable and definite TMJ arthritis were determined. Arthritic TMJs with high inflammatory activity showed higher pain intensity on maximum mouth opening (P<.001) and higher number of painful mandibular movements (P=.004) than TMJs with low inflammatory activity. The combination TMJ pain on maximum mouth opening and Contralateral laterotrusion <8mm appears to have diagnostic value for TMJ arthritis. Among arthritic TMJs, higher TMJ pain intensity on maximum mouth opening and number of mandibular movements causing TMJ pain indicates higher inflammatory activity.

AB0192 EVALUATION OF TEMPOROMANDIBULAR JOINT INVOLVEMENT IN PATIENTS WITH RHEUMATOID ARTHRITIS

ABSTRACTBackground:Temporomandibular joint (TMJ) internal derangement (ID) is a prevalent disorder causing significant pain and dysfunction. Initial treatment typically involves conservative methods, with ozone gas injection emerging as a potential therapy. This study evaluates the efficacy of intra-articular ozone gas injection in treating TMJ ID.Methods:Twenty patients diagnosed with Wilkes stage II and III TMJ ID received ozone gas injections into the periarticular tissues and superior joint space. Maximal interincisal mouth opening and TMJ pain scores were assessed at 28 and 42 days post treatment.Results:There were significant improvements in maximal mouth opening and reductions in TMJ pain scores from baseline to the 42nd day post injection.Conclusion:Intra-articular ozone gas injection offers a minimally invasive, cost-effective treatment for TMJ ID, showing substantial benefits before considering more invasive procedures.

The aim of this study was to explore standard anthropometric airway characteristics of patients with obstructive sleep apnea syndrome (OSAS) and determine the incidence and risk factors for difficult airway management. Final analysis included 91 patients with polysomnography-verified diagnosis of OSAS who underwent sleep breathing disorder surgery under general anesthesia with direct laryngoscopy oroendotracheal intubation. The incidence of difficult manual mask ventilation during anesthesia induction, difficult intubation and immediate postextubation respiratory complications was 17.6%, 7.7% and 7.7%, respectively. Compared to patients without difficult manual mask ventilation, the group of OSAS patients with difficult manual mask ventilation had a higher rate of body mass index (BMI) ≥25 kgm-2 (p=0.010), Mallampati score ≥3 (p=0.024) and Cormack-Lehane score ≥3 (p=0.002). The OSAS patients with difficult intubation had more Cormack-Lehane score ≥3 (p=0.002) in comparison to those without difficult intubation. Our study demonstrated that manual mask ventilation during anesthesia induction was the most troublesome airway management task in OSAS patients during sleep breathing disorder surgery. Cormack-Lehane score was a relevant determinator of difficult mask ventilation and difficult intubation, while Mallampati score and BMI were relevant determinators only for difficult manual mask ventilation.

Management of failed intubation in a septic parturient

Introduction: The management of head and neck surgical patients is associated with increased morbidity and mortality, and so anticipating the difficult airway is important. Methods: We undertook a prospective survey on consecutive adult patients scheduled on the elective operating lists of four head and neck consultant surgeons. Data were collected over a 36 month period. Data included: patient characteristics; routine predictors of difficulty in airway management (bedside tests of the airway, a history of previous surgery or radiotherapy and the presence of airway symptoms); laryngoscopy grade; method of anaesthesia and airway management; and any airway complications arising during induction of anaesthesia and extubation. Results: The ‘study’ group consisted of 818 patients. The ‘direct laryngoscopy’ group contained 674 patients, that is, patients who had direct laryngoscopy and could therefore be classified as easy or difficult intubation. The prevalence of difficult intubation was 12.6%. Factors or tests that were statistically significantly associated with difficult intubation were: history of difficult airway; previous head or neck radiotherapy treatment; presence of airway symptoms; presence of moderate or severe limited neck movement; and short interdental distance. The sensitivity, specificity and positive predictive values were: history of difficult airway 16.5%, 98.6% and 63.6%; previous radiotherapy 12.9%, 96.6% and 35.5%; airway symptoms 42.9%, 69.6% and 15.9%; moderate/severe neck limitation 16.7%, 97.2% and 46.7%; Mallampati score 3 or 4, 38.8%, 83.8% and 25.8%; and interdental distance 9.4%, 98.8% and 53.3%, respectively. The Bonfils intubation fibrescope was the most commonly used indirect laryngoscopy device (63.9% of all such cases). Twenty-six patients (3.2%) had complications during their initial airway management after induction of anaesthesia. There was one case of ‘cannot intubate, cannot oxygenate’, which required an emergency tracheostomy. Conclusion: The prevalence of difficult intubation in head and neck surgical patients was higher than in the general population, but predictive tests for difficult intubation have poor to moderate value. In our study, rates of difficult face mask ventilation, failed intubation and complications during induction and extubation were low. However, serious morbidity, although rare, can still be encountered. Head and neck surgical patients can be managed safely in a tertiary centre where there is appropriate surgical and anaesthetic expertise in managing difficult airways.

Background and objectiveMany tests are at hand to predict difficult intubation preoperatively to prevent morbidity and mortality of unanticipated difficult intubation. The present study was conducted to evaluate and compare the efficacy of the modified Mallampati test (MMT) and upper lip bite test (ULBT) to foresee difficult intubation.Materials and methodsAfter obtaining written informed consent, this prospective comparative observational study was conducted on 225 patients scheduled for elective surgery under general endotracheal anesthesia. Preoperative MMT and ULBT were performed. MMT Grade III, IV, and ULBT Grade IV were regarded as predictors of difficult intubation. The laryngoscopic view was graded as per Cormack and Lehane's laryngoscopic grading after induction of anesthesia by an experienced anesthesiologist ignorant of preoperative airway evaluation. Patients with Cormack and Lehane Class III and IV were regarded as difficult intubation. Sensitivity, specificity, and positive and negative predictive values of MMT and ULBT were computed. Agreement between two tests with the Cormack Lehane test was determined by the Kappa coefficient.ResultsIn our research, the occurrence of difficult intubation was found to be 10.2% (23 cases of difficult intubation out of 225 patients). In our analysis, we found the sensitivity (95.5% vs. 95.4%), specificity (54.8% vs 50.0%), positive predictive value (91.6% vs 93.1%), and negative predictive value (39.1% vs 39.1%) were almost comparable between modified Mallampati test and upper lip bite test. Kappa coefficient for the upper lip bite test (0.492) was slightly higher as compared to modified Mallampati scoring (0.454), but both the values are highly statistically significant (p-value <0.001).ConclusionBoth the upper lip bite test and modified Mallampati test are comparable with each other and since the upper lip bite test is easy to perform bedside test we recommend it to be used alone or in collaboration with other tests in assessing difficult airways.