Thyromental Distance Research Articles

Observation of the validity of the upper lip bite test in predicting difficult intubation

The upper lip bite test (ULBT) is considered an effective method for predicting difficult airways, but data on the ULBT for predicting difficult tracheal intubation are lacking. This study aimed to examine the clinical utility of the ULBT in predicting difficult endotracheal intubation. We conducted an observational case-cohort study of adult patients undergoing elective surgery and requiring endotracheal intubation for general anesthesia. Difficult airway assessment was performed on the recruited patients before the operation, including the ULBT, mouth opening, thyromental distance, modified Mallampati test, and body mass index. The primary outcome was the incidence of difficult tracheal intubation. The receiver operating characteristic curve analysis was used to compare the performance of variables in predicting difficult tracheal intubation. We successfully recruited 2522 patients for analysis and observed 64 patients with difficult tracheal intubation. When predicting difficult tracheal intubation, grade 2 ULBT had a sensitivity of 0.75 and a specificity of 0.54, and grade 3 had a sensitivity of 0.28 and a specificity of 0.75. Compared with mouth opening, the area under the receiver operating characteristic curve of the ULBT was lower in predicting difficult tracheal intubation (0.69 [95% confidence interval: 0.67–0.71] vs. 0.84 [95% confidence interval: 0.82–0.87], P < 0.05).Clinical Trials Registry: ChiCTR-ROC-16009050, principal investigator: Weidong Yao.

Comparison between clinical and ultrasonographic parameters in predicting difficult airway: An observational prospective study

Introduction : Various clinical tests are applied at the bedside to predict difficult airway during the pre-anaesthetic examination. Ultrasonography can be used to evaluate the airway and predict difficulty in laryngoscopy and endotracheal intubation.&#x0D; Objective : To compare the various clinical and ultrasonographic parameters in predicting difficult airway.&#x0D; Methodology: This prospective observational study was carried out at Birat Medical College and Teaching Hospital. The clinical parameters obtained were Modified Mallampati Grade (MMP), Upper Lip Bite Test (ULBT) and Thyromental Distance (TMD) and the ultrasonographic (USG) parameters used were Tongue Volume (TV), Hyomental Distance Ratio (HMDR) and distance of soft tissue from skin to hyoid bone (DSHB).These results were correlated with Cormack-Lehane (CL) grade during laryngoscopy of 200 patients. The sensitivity, specificity, Receiver Operating Characteristic (ROC) curve along with Area under the curve (AUC) was calculated for each parameter.&#x0D; Result: Incidence of difficult airway was 15.5%. The sensitivity and specificity of ultrasonographic tongue volume (TV) was higher among all parameters in predicting difficult airway. The specificity of HMDR and DSHB were better compared to clinical parameters.&#x0D; Conclusion: The use of ultrasound in pre-anaesthetic examination can be a viable tool along with clinical parameters for prediction of difficult airway.

Diagnostic Accuracy Of Ultrasound For Confirmation Of Endotracheal Tube Placement Taking Capnography As A Gold Standard

Introduction: Accurate placement of an endotracheal tube (ETT) is critical for patient safety during medical procedures. The research explores the potential of ultrasound technology to provide a reliable alternative for ETT confirmation, offering insights into its diagnostic performance and the implications for enhancing patient care in surgical settings.&#x0D; Aims &amp; Objectives: To determine the diagnostic accuracy of ultrasound for the confirmation of endotracheal tube keeping Capnography as a Gold standard.&#x0D; Place and Duration of Study: It is a Cross Sectional study and the study was carried out in Operation Theater Shaikh Zayed Hospital Lahore, within 6 months after approval of synopsis i.e. from 5th May, 2020 till 4th November, 2021.&#x0D; Material &amp; Methods:Total 219 patients who fulfilled the inclusion criteria were enrolled. After standardization of anesthetic measures all patients were intubated by direct laryngoscopy. ETT placement was assessed by capnometry and by ultrasonography. Endotracheal tube placement was labeled (as per operational definition) on both the techniques.The analysis of the data was conducted using SPSS version 21.0, a p-value of ?0.05 was considered significant.&#x0D; Results: The mean age, BMI, neck circumference and thyromental distance of the patients was 39±8.15 years, 27±3.42 Kg/m 2, 29.5±4.63cm and 6.9±0.50cm. There were 58% males and 42% females in the study. Ultrasonography exhibited sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy rates of 98.5%, 90.6%, 98.9%, 86.1%, and 97.7%, respectively, in its ability to detect the accurate placement of endotracheal tubes (ETT).&#x0D; Conclusion: The sensitivity, specificity, diagnostic accuracy and promptness of recognition for confirmation of tracheal placement of ETT is higher withultrasonography compared to the gold standardcapnography in patients undergoing elective surgery under general anesthesia.

Assessment of airway parameters in obstetric patients and comparing them at different phases in the perinatal period: A prospective observational study.

Airway changes occur in different stages of pregnancy. We aimed to evaluate the changes in the upper airway in obstetric patients during pregnancy, labour and after delivery using multiple airway indices and identify the predictive factors of these changes. This observational study was conducted on 90 parturients aged >20 years, having monofoetal pregnancy. The patient's weight was noted, airway assessment including Mallampati grading (MPG), and thyromental distance (TMD), sternomental distance (SMD), neck circumference (NC) and Wilson's risk score were measured in the second trimester of pregnancy (T0), between 32 and 34 weeks of gestation (T1), at the time of admission for safe confinement, between 38 and 40 weeks of gestation (T2), 2 h after delivery of baby (T3) and, 24 h after delivery (T4). Unpaired t-test and analysis of variance test were applied. Changes in mean (standard deviation [SD]) weight, recorded from T0 to T2, were from 56.96 (10.77) to 65.322 (11.49) kg (P = 0.001). A rise of one or two grades in MPG was detected as the pregnancy progressed, and a decrease of one grade was noted after delivery. A significant decrease in mean (SD) TMD was noted from 6.88 (0.65) to 6.36 (0.62) cm from T0 to T2 (P = 0.001). SMD also decreased in a similar manner as TMD. NC increased from T0 to T3 and then decreased at T4 (P = 0.004). Following the second trimester of pregnancy, MPG increased by either one or two grades, with a decrease in TMD and SMD and an increase in NC.

Evaluation of thyromental height test as a single anatomical measure for prediction of difficult laryngoscopy: a prospective observational study

BackgroundPreoperative airway assessment is essential to predict difficult airway so that adequate planning could be made to secure the airway. Various airway tests have been devised to improve diagnostic accuracy but none of the tests individually have proven to be adequate. Recently, a new airway predictor thyromental height test (TMHT) appears to be a more accurate predictor of difficult laryngoscopy than the existing anatomical measurements. The aim of this study is to evaluate the accuracy of the TMHT and compare it with various screening tests to determine whether TMHT can prove to be a more comprehensive and accurate test for predicting difficult laryngoscopy. Total 150 patients aged > 18 years of either sex with American Society of Anaesthesiologist physical status I—III scheduled for elective surgery under general anaesthesia requiring tracheal intubation were included in this prospective observational study. All patients were subjected to a preoperative airway assessment test including TMHT, modified Mallampati test, upper lip bite test, interincisior gap, thyromental distance and sternomental distance. Intraoperatively direct laryngoscopy was done and the grading of laryngoscopic view was done according to CL.ResultsThe preoperative data and CL grading were used to evaluate the accuracy of TMHT and compared the sensitivity, specificity, positive and negative predictive value with other tests.Twenty six (17.33%) patients had difficult laryngoscopy and 18 patients (12%) required bougie/stylet to facilitate intubation. TMHT had the highest sensitivity (76.92%), specificity (98.38%), PPV (90.90%), NPV (95.31%) and accuracy (94.67%) when compared to other tests.ConclusionsTMHT is a simple bedside test with higher sensitivity and specificity for predicting difficult laryngoscopy as compared to other screening tests.Future study should be done to define ethinicity, race, age groups and gender specific cut off values of TMHT for accurate validation of prediction in difficult laryngoscopy.

Evaluation of thyromental distance versus tongue width versus weight-based method for size determination of laryngeal mask airway in adults

Background: Supraglottic airway devices (SGD) are indispensable for airway management. The successful placement of the laryngeal mask airway (LMA) supreme largely depends on the right size selection. Aims and Objectives: The study was undertaken to compare three LMA supreme insertion methods in short elective surgeries under general anesthesia. Materials and Methods: Atotal of 90 American Society of Anesthesiologists I and II patients (either gender, 18–55 years, Mallampati grade I and II) undergoing short surgeries were randomized into three equal groups (n=30 in each). Insertion of LMA was done after an adequate depth of anesthesia for jaw relaxation (Young’s criteria). The efficacy of controlled ventilation through LMA by each method, success rate, ease of insertion, insertion time, additional induction dose (propofol) required during insertion, hemodynamic stability (baseline vitals and 10 min after insertion), and adverse events after LMA removal were evaluated between groups. Results: Better ventilation (tidal volume at 10 cmH2O) was observed in the thyromental group (448±35) than in tongue width (440±46) and weight-based (409±33) groups. Minimum additional propofol requirement during insertion was in thyromental distance group. Thyromental distance group had the most easy LMA insertions (70%) with minimum insertion time (10±4) and minimum additional propofol requirement during insertion (P&lt;0.05) than other groups. Overall hemodynamic stability and incidence of adverse events were comparable. Conclusion: Thyromental distance may be an alternative attractive choice for size determination of LMA supreme in female adults with normal airway anatomy in comparison to tongue width and conventional body weight-based methods.

Assessment of Preoperative Predictors for Difficult Laryngeal Exposure in Endolaryngeal Surgery.

The proper visualisation of the larynx is required for the diagnostic assessment and therapeutic intervention. The most significant challenges for surgeon is to visualise the anterior commissure of the glottis region. The aim of this study is to record the preoperative laryngoscore in patients posted for endolaryngeal surgery and to assess preoperative predictors for intraoperative difficult laryngeal exposure by correlating with preoperative laryngoscore. Prospective, Cross-sectional, Observational study. Department of Otorhinolaryngology in a tertiary care teaching facility. 150 patients were included with an endolaryngeal disease who were planned for surgery with age > 18yrs. In 150 subjects preoperative laryngoscore was calculated, which comprised 11 parameters including thyromental distance, mandibular prognathism, macroglossia, micrognathia, trismus, inter incisor gap, degree of neck flexion-extension, history of prior open-neck surgery or radiotherapy, upper jaw dental status, modified Mallampati score and body mass index in order to produce a total score out of a possible maximum score of 17. According to the anterior commissure visualisation all patients were categorised into five classes, ranging from class 0 to class IV during surgery. The laryngoscore parameters were assessed and compared statistically with five classes of intraoperative anterior commissure visualisation. Out of 150 patients 70 (46.6%) were having 3-4 laryngoscore, followed by 45 (30%) patients with 5-6 laryngoscore. Total 123 (82%) patient had class 0,1 and 2 intraoperative anterior commissure visualisation while 27 (18%) had class 3 and 4 visualisation. If laryngoscore was either less or equal to 5, 90% of the patients had excellent laryngeal exposure whereas only 10% of the patients had challenging laryngeal exposure. At univariate analysis, thyromental distance, degree of neck flexion/extension, and modified Mallampati classification were found statistically significant for difficulty of anterior commissure visualisation independently. A sound, easy and valid preoperative laryngoscore may be significantly helpful in identifying intraoperative difficult laryngeal exposure. This may prevent inadequacy of surgery, abandon of surgery, intra operative complication, and medico-legal cases for laryngologist.

Intubation challenges in surgeries of thyroid swellings

Background: Difficult airway is when a trained anesthesiologist experiences difficulty with face mask ventilation of the upper airway or tracheal intubation or both. It has always been a challenging issue for anesthesiologists. Aims and Objectives: The objective was pre-operative assessment of airway in patients with goiter and to find the incidence of difficult intubation and its management. Materials and Methods: A prospective study was done in 32 patients presenting with goiter of various sizes. Routine airway examination includes mouth opening, Mallampati grading, neck circumference, neck mobility, thyromental distance, tracheal deviation on chest X-ray, AP and lateral views of neck, and Cormack-Lehane grading on laryngoscopy. The technique followed in each case was noted. Results: Out of 32 cases, difficult intubation was experienced in five cases. Among the studied parameters, neck mobility (66.7%) followed by neck circumference (44.4%) and Mallampati grading (37.5%) was found to be more predictive in assessing the airway. 62.5% patients were intubated through direct laryngoscopy, followed by bougie in 21.9% patients. Due to difficulty in intubation, 15.6% patients were intubated through videolaryngoscopy. Conclusion: We conclude that induction of anesthesia can be challenging for patients with goiter. A thorough history and examination are mandatory pre-operatively in these patients. Neck circumference and neck mobility are the most crucial factors as evident in our study. Videolaryngoscopy plays an important role in patients with difficult airway.

To Evaluate Usefulness of Stop-Bang Questionnaire in Predicting Difficult Bag Mask Ventilation and Difficult Intubation in Adult Patients for Elective Surgery: Important Guide for Obstructive Sleep Apnea Patients

Introduction: Obstructive sleep apnea (OSA) is a condition with repetitive interruptions to breathing due to obstruction of the airway in sleep. We evaluated STOP-BANG score outcome. Aim and Objective: To evaluate the usefulness of stop-bang questionnaire in predicting difficult bag mask ventilation and difficult intubation (DIT) with comparison. Materials and Methods: A prospective, simple randomized, comparative study was on 100 patients. Results: O group had male preponderance, higher American Society of Anesthesiologists grades along with comorbidities, higher mallampati grades, lower sternomental distance and thyromental distance, and higher neck circumference. Mean time in study group was 31.7 s and in control group was 18.68 s. Conclusion: We conclude that patients with STOP-BANG score ≥3 are at higher risk of unanticipated difficult mask ventilation and DIT in undiagnosed cases of OSA.

Comparison of Ultrasound Parameters and Clinical Parameters in Airway Assessment for Prediction of Difficult Laryngoscopy and Intubation: An Observational Study.

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.

Development and validation of a nomogram for difficult laryngoscopy at visual laryngoscopy: a prospective nested case-control study.

Unsuccessful airway management is associated with increased perioperative morbidity and mortality. Difficult laryngoscopy is a leading cause of unanticipated difficult airways and presents a challenge for anesthesiologists. Airway ultrasound assessment can be used as a priority diagnostic strategy for difficult laryngoscopy because of its diagnostic performance in difficult airways. This study was designed to develop a comprehensive model based on multivariate statistical analysis (including bedside examination tests and ultrasonography) for difficult laryngoscopy. This study was conducted from December 27, 2021, to September 16, 2022. All patients underwent an airway ultrasonographic measurement with a standard operating procedure. The baseline characteristics and bedside examination tests were also recorded. Laryngoscopy with a Cormack-Lehane (CL) grade of 1-2 was defined as "easy laryngoscopy", whereas "difficult laryngoscopy" was based on a CL grade of 3-4. The prediction model was built by using baseline characteristics, bedside examination tests, and ultrasonographic measurements as independent variables and easy/difficult laryngoscopy as the dependent variable. A total of 516 patients were eligible, and 456 patients were finally enrolled in the study. A 4-variable analysis, including inter-incisor gap (IIG), thyromental distance (TMD), the distance from the skin to the tongue root, and airway-related diseases, was performed to construct the optimum prediction model. The area under curve (AUC) value of the prediction model was 0.933 [95% confidence interval (CI): 0.770 to 0.935] in the training set and 0.956 (95% CI: 0.915 to 0.997) in the validation set. The comprehensive model and nomogram, especially the integration of tongue root thickness, can predict the risk of difficult laryngoscopy more accurately and reliably than any other screening method alone, allowing for reasonable individualized regimen decision-making.

Anaesthesiologic and intensive care particularities in cervical surgery

Abstract BACKGROUND. Endotracheal intubation is frequently used to maintain airways proper functioning during elective surgical operations, in intensive care and in emergency rooms. The pathology of the oropharyngeal and laryngeal area or that of the cervical area induces, in most cases, changes in the airways, especially in the sense of their narrowing or deviation. The presence of tumors on the oro-pharyngo-laryngeal axis, some bleeding easily spontaneously or upon touch, can make the anaesthetic procedure difficult. MATERIAL AND METHODS. We conducted a prospective, observational study on 50 patients with cervical pathology who required general anaesthesia during 2019-2021. The criteria and parameters analysed for predicting difficult intubation were the duration of orotracheal or nasotracheal intubation, difficult face mask ventilation, Cormack-Lehane and Mallampati scores, anthropometric determinations of various cervical landmarks, including the thyromental distance, the distance between the arytenoid cartilages and the distance from the plane of the arytenoid cartilages to the skin, both of the latter determined ultrasonographically. RESULTS. The following statistically significant differences emerge from the study: the duration of orotracheal intubation (p&lt;0.001), the difficulty of face mask ventilation (p&lt;0.001), the intercondylar distance (p=0.042), the intermastoid distance (p=0.023), the Cormack-Lehane score (p=0.013), the Mallampati score (p=0.004), the distance between the arytenoid cartilages (p=0.007), the distance between the plane of the arytenoid cartilages and the skin (p&lt;0.001). All were increased in patients with tumoral pathology. CONCLUSION. The study demonstrates the variation of new criteria and parameters that can be analysed for the prediction of a difficult airway, identifies the efficiency of using ultrasound whenever possible in the preanesthetic evaluation of the airway, and quantifies the risk of difficulty in airway management based on anthropometric data, particularly through the occurrence of asymmetry at the cervical or facial level.

Gravida 7 para 4 abortus 2 (G7P4A2) for multiple repeat caesarean section: general or neuroaxial anesthesia

A caesarean section (CS) is a surgical procedure that has several risks, such as uterine rupture, infection, bleeding, thrombosis, and damage to the bladder, ureters, or intestines. Compared to primary CS, multiple repeat caesarean sections (MRCS) are associated with additional risks, including placenta previa, abnormal placental invasion, difficulty in surgical dissection, longer surgeries, and greater amounts of bleeding. A woman, age 40 years, G7P4A2, gravida aterm, weight 64.4 kg, height 150 cm, Mallampati score 1, open mouth &gt;3 cm, thyromental distance &gt; 3 fingers, neck circumference 33 cm, former caesarean section 4 times, would have her caesarean section and sterilization at Melinda Woman Hospital Bandung-Indonesia. A caesarean section was performed under general anesthesia, induction with propofol, atracurium, and sevoflurane, and maintenance anesthesia with N2O/O2-sevoflurane. Induction-delivery time: 16 minutes, uterine incision 50 seconds, baby born with 1-minute Apgar score was 9 and 5-minute Apgar score was 10. Analgetic fentanyl is given after birth at a dose of 1.5 mcg/kgBw intravenously. There were no caesarean-section complications. Postoperatively, the patient was treated in the wards. Due to concerns about heavy bleeding, which would require massive transfusions, anesthesia was performed under general anesthesia due to the fact that massive transfusions make patient uncomfortable because of various complications of massive transfusion

Thyomental distance is a good difficult airway indicator: Truth or a misconception- A prospective observational study

Unanticipated difficult intubation can be a true challenge to any anaesthesiologist. The most widely used determinant till date in almost every airway study is Thyromental distance[TMD]. We aimed to determine if a TMD above the average values could indicate difficult intubation.70 patients were selected in this prospective observational study who require general anesthesia with endotracheal intubation for their respective surgeries. Patients who fulfilled the inclusion criteria were enrolled in the study and informed written consent was taken.Routine pre-anesthetic check up was done. Thyromental distance was measured [thyroid notch to the lower border of the mandibular mentum-head fully extended] using a rigid ruler. Intraoperatively: After following standard general anaesthesia protocol, patients were intubated by anesthesiologist with atleast 2 years of experience and blinded to the study. The ease (0-5) / Difficulty (&amp;#62;5) in intubation was assessed with Intubation difficulty scale(IDS). Data was analysed using SPSS Software 16. Data was expressed in terms of frequency and percentage. In a total of 70 patients, 18.6% of the patients had difficult intubation. It was observed that 50 patients had a TMD &amp;#62;=7.5 cm out of whom, 7 patients were difficult to intubate. 12 patients had TMD&amp;#60;6.5 cm out of which 6 patients had an IDS of &amp;#62;5 indicating difficult intubation. Sensitivity, specificity, PPV, NPV were calculated. Categorical Pearson chi square test was done for TMD&amp;#62;7.5 vs IDS and it showed a p value of 0.017 (p&amp;#60;0.05).We observed that a long TMD (TMD&amp;#62;=7.5cm) could be a difficult airway indicator just like a short TMD (TMD&amp;#60;=6.5). Therefore, our findings suggest that thyromental distance may not have a significant role as a standalone pre-operative indicator of a difficult airway and its reliability as a useful parameter in predicting difficult intubation is questionable.

Prognostic value of the intubation difficulty scale in bariatric surgery

The objective was to assess the predictive value of the risk scale for difficult intubation in obese patients. Materials and methods. The object of the study was 110 patients (90 women and 20 men) operated on as planned in 2022. The mean age of the patients was 42 ± 11 years. The median body mass index (BMI) was 43.7 kg/m 2 (Q1–Q3: 37.9–49.1). All patients underwent a standard preoperative examination with the identification of the risk of difficult airways according to the intubation difficulty scale (IDS): mouth opening, neck mobility, mandibular protrusion, Mallampati class, sternomental and thyromental distances, and history of previous intubations were assessed. Results. Difficult intubation (3–4 degrees according to Cormack–Lehane) were detected in 19 patients (17.3 %). ROC-analysis revealed the dependence of the probability of difficult intubation on the total points on the intubation difficulty scale. The area under the ROC curve was 0.809 ± 0.063 with 95 % CI: 0.685 – 0.932. The model was statistically significant (p &lt; 0.001). The cut-off point value for the total points on the intubation difficulty scale, which corresponded to the highest value of the Youden index, was 4. The sensitivity and specificity of the model were 100.0 % and 47.3 %, respectively. Significant differences (p &lt; 0.001) were found in the analysis of the risk of difficult intubation depending on the total points on the intubation difficulty scale. The most significant differences (p &lt; 0.001) were demonstrated by the mouth opening width and neck mobility. There were no differences (p = 0.547) when analyzing the history of difficult airways and nighttime snoring. Conclusion. Overall, the intubation difficulty scale showed predictive value in terms of assessing the risk of difficult airways (p = 0.002, χ2 = 13.230). The most reliable indicators for predicting the risks of difficult intubation were mouth opening less than 4 cm (p &lt; 0.001, χ2 = 11.185) and head and neck flexion in the atlanto-occipital joint less than 90о (p &lt; 0.001, χ2 = 10.858). Assessment of thyromental and sternomental distances, mandibular protrusion ability, and Mallampati class also showed statistical significance. Prior history of difficult intubation and nighttime snoring showed no statistically significant risk in predicting difficult airways (p = 0.547, χ2 = 0.363).

Difficult Intubation Predictor: Comparison Between Ratio Of Height To Thyromental Distance, Mallampati Score And Thyromental Distance

Introduction: The Mallampati score and thyromental distance (TMD) are frequently used to identify challenging laryngoscopies, but their reliability in predicting difficulty is uncertain. This study aims to assess the effectiveness of using the ratio of height to thyromental distance (RHTMD) in predicting difficult visualization of the larynx (DVL) when compared to the Mallampati score and TMD.Method: To achieve this goal, 277 patients who received general anesthesia during elective surgery were evaluated using the Mallampati score, TMD, and RHTMD. The Cormack and Lehane (CL) classification was used to grade the laryngeal view, with CL grade 3 and 4 indicating difficult visualization. The study then determined and compared the area under the curve (AUC), sensitivity, and specificity for each airway predictor.Results: The AUC of RHTMD (85.5%) was better than TMD (82.7%) and significantly better than the Mallampati score (61.4%).Conclusion: RHTMD is more accurate in predicting difficult laryngoscopy than both the Mallampati score and TMD.

Retrospective Investigation of Difficult Airway Cases Encountered in Bursa Uludag˘ University Medical Faculty Operating Room.

Ensuring airway patency and proper management of ventilation by anticipating difficulties that can occur in airway control are vital in preventing anaesthesia-related complications. We aimed to determine the role of preoperative assessment findings in difficult airway management. In this study, critical incident records of difficult airway patients between 2010 and 2020 in the operating room of Bursa Uludag˘ University Medical Faculty were retrospectively analysed. A total of 613 patients, whose records were fully accessible, were grouped as paediatric (under 18 years old) and adult (18 years and over). The success rate for maintaining an airway in all patients was 98.7%. Pathological situations which cause difficult airways were head and neck region malignancies in adult patients and congenital syndromes in paediatric patients. Anatomical reasons that cause difficult airway were anterior larynx (31.1%) and short muscular neck (29.7%) in adult patients and small chin (38.0%) in paediatric patients. A significant statistical relationship was found between difficult mask ventilation and increased body mass index, male gender, modified Mallampati class 3-4, and thyromental distance <6 cm (P = .001, P < .001, P < .001, and P < .001, respectively). The correlation of Cormack-Lehane grading with modified Mallampati classification, upper lip bite test, and mouth opening distance was statistically significant (P < .001, P < .001, and P < .001, respectively). In male patients with increased body mass index, modified Mallampati test class of 3-4 and thyromental distance of < 6 cm should suggest the possibility of difficult mask ventilation. In modified Mallampati classification and upper lip bite tests, the possibility of difficult laryngoscopy should be considered as class increases and mouth opening distance becomes shorter. Preoperative assessment, including a good history taken from the patient and a complete physical examination, is crucial to provide solutions for difficult airway management.

A Comparative Study to Evaluate Difficult Intubation Using Ratio of Patient Height to Thyromental Distance, Ratio of Neck Circumference to Thyromental Distance and Thyromental Height in Adult Patients in Tertiary Care Centre.

Patients' airway assessment is one of the foremost responsibility of every anaesthesiologist. Several preoperative predictive methods have been studied by various authors to find the best difficult airway predictor. We conducted this study to compare three methods to predict difficulty of laryngoscopic endotracheal intubation viz Ratio of patient Height to Thyro-Mental Distance (RHTMD), Ratio of Neck Circumference to Thyro-Mental Distance (RNCTMD) and Thyro-Mental Height (TMHT) in adult patients. This prospective observational study was conducted on 330 adult patients, ASA staus I and II, aged 18-60 years of either sex, weighing 50-80 kg scheduled for elective surgeries under general anaesthesia. Patient's height, weight, Body Mass Index (BMI) was recorded and thyromental distance, neck circumference, TMHT were measured preoperatively. Laryngoscopic view was graded according to Cormack- Lehane (CL) Grade. Predictive indices and optimal cut-off values were calculated using ROC curve analysis. Difficulty in laryngoscopic endotracheal intubation was encountered in 12.42% patients. The sensitivity, specificity, positive predictive value, negative predictive value and Area Under Curve (AUC) for TMHT were 100%, 95.2%, 75.54%, 100%, 0.982; for RHTMD were 75.6%, 72.7%, 28.18%, 95.45%, 0.758 and for RNCTMD were 82.9%, 65.4%, 25.37%, 96.42%, 0.779 respectively. There was no statistically significant difference to predict difficulty of laryngoscopic intubation between any of them (P < .05). Among these 3 parameters, TMHT was found to be the best preoperative method to predict difficult laryngoscopic endotracheal intubation with highest predictive indices and AUC. The RNCTMD was found to be more sensitive and useful method than RHTMD to predict difficulty of laryngoscopic endotracheal intubation.

Evaluation of neck-circumference- thyromental- distance ratio as a predictor of difficult intubation: A prospective, observational study.

Preoperative identification of difficult airway and subsequent planning is of utmost importance for a patient's safety. Previous studies have identified the ratio of the neck circumference (NC) to the thyromental distance (TMD); NC/TMD as a reliable predictor of difficult intubation in obese patients. But there is a lack of studies evaluating the NC/TMD in non-obese patients. Therefore, the aim of this study was to compare the NC/TMD as a predictor of difficult intubation in both obese and non-obese patients. A prospective, observational study was conducted after obtaining institutional ethics committee clearance and written and informed consent from each patient. One hundred adult patients undergoing elective surgeries under general anaesthesia with orotracheal intubation were included in this study. Difficulty in intubation was assessed using the Intubation Difficulty Scale. The NC/TMD was calculated and the predictive accuracy of NC/TMD and other established parameters in obese and non-obese patients were compared. Univariate logistic regression analysis showed that gender, weight, body mass index, inter-incisor gap, Mallampati classification, NC, TMD, sternomental distance, and NC/TMD had a significant association with difficult intubation. NC/TMD has a higher sensitivity, specificity, and positive and negative predictive value with better predictability in comparison to other parameters. The NC/TMD is a reliable and better predictor of difficult intubation in both obese and non-obese patients in comparison to NC, TMD, and sternomental distance alone.

USG guided indices as a tool for prediction of difficult airway in obese: an observational study

Background: Now a days, Ultrasound has been the gold standard and an invaluable tool in the field of regional anaesthesia, especially for upper limb and truncal blocks where general anesthesia is associated with high risk and also in patients posted for general anesthesia with anticipated difficult airway. Recently, few studies have published the importance of Ultrasound in the evaluation of airway and related procedures. Aim of this study is to evaluate the use of USG guided indices for prediction of difficult airway in obese patients and correlating them with clinical parameters. Methods: This study was a prospective observational study done in a tertiary health care center, Government General hospital, Kakinada over a duration of two months from August 2022 to September 2022. Eight Ultrasound parameters like tongue thickness, skin to hyoid distance, pre-epiglottic space, skin to midpoint of vocal cords, skin to thyroid isthmus, anterior soft tissue thickness at suprasternal notch, hyomental distance and thyromental distance were correlated with clinical evaluation (Cormacke-lehane grading) in this study and conclusions were drawn. Results: Out of 30 cases studied, 20 (70%) were predicted to be difficult with Ultrasound airway examination and 16 (53.3%) were found to have difficulty in intubation clinically. Conclusions: The following USG indices like pre-epiglottic space, Skin to midpoint of vocal cords, Anterior soft tissue thickness at Suprasternal notch, Hyomental distance in mid-extended position and thyromental distance were found to be clinically correlated to predict difficult airway and intubation in obese patients.