Prediction Of Difficult Tracheal Intubation Research Articles

Comparison of the modified Mallampati classification score versus the best visible Mallampati score in the prediction of difficult tracheal intubation: a single-centre prospective observational study.

The modified Mallampati classification is part of the preoperative airway risk assessment. Inconsistency in the way it is examined may contribute to heterogeneity in its diagnostic performance. The best visible Mallampati score could reduce interobserver heterogeneity but its diagnostic characteristics remain unknown. During preoperative anesthesia consultation of adult patients with a senior anesthesiologist, we compared the modified Mallampati classification score vs the best visible Mallampati score using cervical extension, tongue in, and phonation. The primary outcome was the diagnostic characteristic of the modified Mallampati classification score vs the best visible Mallampati score as predictors of difficult orotracheal intubation (more than two direct laryngoscopies or need for an alternate device). We performed a multivariable analysis to identify independent predictors of difficult orotracheal intubation in the tested cohort. Difficult orotracheal intubation occurred in 77/3,243 (2.4%) patients. A best visible Mallampati score was obtained in 1,596 (49.2%) patients. Sensitivity and specificity of the modified Mallampati classification score for predicting difficult orotracheal intubation were 0.56 (95% confidence interval [CI], 0.44 to 0.66) and 0.69 (95% CI, 0.68 to 0.71), respectively. By comparison, the best visible Mallampati score was less sensitive (difference, -0.30; 95% CI, -0.19 to -0.30; P < 0.001) but more specific (difference, 0.24; 95% CI, 0.22 to -0.25; P < 0.001). In patients with difficult orotracheal intubation, 53% were incorrectly reclassified as low risk by the best visible Mallampati score. Compared with the modified Mallampati classification score, the best visible Mallampati score decreased sensitivity for predicting difficult orotracheal intubation and falsely classified half of the patients with difficult orotracheal intubation. Taking the risks associated with difficult airways into account, our findings indicate that a careful examination of the modified Mallampati classification is required during the global preoperative airway examination. ClinicalTrials.gov ( NCT02788253 ); 9 February 2016.

Modified Mallampati Test in Supine versus Sitting Position as a Predictor for Difficult Intubation – An Observational Study

Abstract Background: The modified Mallampati test (MMT) is routinely employed to predict difficult laryngoscopy and tracheal intubation. This test, as a standard, when conducted with a patient in a sitting position, exhibits limited practicality due to its relatively low sensitivity and specificity in predicting difficult tracheal intubation (DTI). It is hypothesised that MMT, when performed with a patient lying supine, may improve its efficacy as a predictor of DTI. Methods: This single-centre prospective observational study was conducted involving 455 adult patients requiring general endotracheal anaesthesia. During preanaesthetic evaluation, MMT was performed in the sitting position as a standard (sitting MMT). Subsequently, independent observers recorded the MMT in the supine position (supine MMT) before administering general anaesthesia. The sitting and supine MMT were correlated with Cormack and Lehane grades using the Chi-square test. Diagnostic performance metrics, including the area under the receiver operating characteristic (ROC) curve, sensitivity, specificity, positive predictive values (PPV) and negative predictive values, were employed to assess the predictive capabilities of MMT in both positions. Results: Out of 455 patients, 72 (15.8%) experienced difficult intubation (defined as Cormack–Lehane Grade III and above). Both MMT in the sitting and supine positions demonstrated strong predictive capabilities for DTI, with areas under the ROC of 0.799 and 0.779, respectively. While sitting in the MMT position exhibited higher sensitivity (55.6% vs. 28.8%), supine MMT demonstrated a superior PPV (86.1% vs. 55.6%). Conclusion: MMT, when conducted with a patient in a supine position emerges as an alternative and a reliable predictor for predicting DTI.

Predictors of Difficult Tracheal Intubation in Thyroid Surgery

Predictors of Difficult Tracheal Intubation in Thyroid Surgery

Predictors of difficult tracheal intubation during general anaesthesia: an analysis of an obstetric airway management registry

Predictors of difficult tracheal intubation during general anaesthesia: an analysis of an obstetric airway management registry

Comparison of Mallampati test in sitting position and in supine position for prediction of difficult tracheal intubation among adult patients who underwent surgery under general anesthesia at Addis Ababa governmental hospitals 2021, comparative cross-sectional study.

BackgroundThe Mallampati test is used to evaluate the airway to predict difficult laryngoscopy and intubation. The sitting position is the standard for this test, but it has limited practical utility due to its low sensitivity and moderate specificity in predicting difficult intubation and laryngoscopy. The supine position, on the other hand, may improve its efficacy.ObjectiveTo assess the Mallampati test in sitting and supine positions on predicting difficult laryngoscopy and intubation among Adult surgical patients undergoing general anesthesia in selected governmental hospitals of Addis Ababa.MethodA cross-sectional study was conducted on 403 adult patients who underwent surgery that required endotracheal intubation. The preoperative Mallampati test in sitting and supine positions was compared to the Cormac and Lehan grade and Intubation Difficulty Scale using the chi-square test. The Statistical Package for Social Sciences (SPSS) software version 26.0 was used to analyze the data. A p-value of less than 0.05 was used to determine statistical significance. As statistical measurements, sensitivity, specificity, positive predictive values, and negative predictive values were calculated.ResultThe incidence of difficult laryngoscopy and intubation is 13.7% and 9.7% respectively. Supine positions show a sensitivity of 78.8%; specificity of 93%; a positive predictive value of 64.1 and a negative predictive value of 96. Whereas sitting shows sensitivity of 75%; specificity of 96.3%; positive predictive value of 76.5 and negative predictive value of 96 concerning difficult laryngoscopy. Related to difficult intubation supine shows a sensitivity of 78.4%; 89.8% specificity; 45.3 positive predictive value and 97.5 negative predictive values, whereas sitting shows 73% sensitivity, 93% specificity, 52.9% positive predictive value and 97% negative predictive value.Conclusionand recommendation: For predicting difficult tracheal intubation and laryngoscopy, sitting has a high specificity and positive predictive value, but supine has high sensitivity and negative predictive value. Despite its poor positive predictive value, supine has a comparable prediction for difficult intubation therefore it can be used as an alternative approach.

Nomograms for predicting difficult airway based on ultrasound assessment

BackgroundAccurate prediction of the difficult airway (DA) could help to prevent catastrophic consequences in emergency resuscitation, intensive care, and general anesthesia. Until now, there is no nomogram prediction model for DA based on ultrasound assessment. In this study, we aimed to develop a predictive model for difficult tracheal intubation (DTI) and difficult laryngoscopy (DL) using nomogram based on ultrasound measurement. We hypothesized that nomogram could utilize multivariate data to predict DTI and DL.MethodsA prospective observational DA study was designed. This study included 2254 patients underwent tracheal intubation. Common and airway ultrasound indicators were used for the prediction, including thyromental distance (TMD), modified Mallampati test (MMT) score, upper lip bite test (ULBT) score temporomandibular joint (TMJ) mobility and tongue thickness (TT). Univariate and the Akaike information criterion (AIC) stepwise logistic regression were used to identify independent predictors of DTI and DL. Nomograms were constructed to predict DL and DTL based on the AIC stepwise analysis results. Receiver operating characteristic (ROC) curves were used to evaluate the accuracy of the nomograms.ResultsAmong the 2254 patients enrolled in this study, 142 (6.30%) patients had DL and 51 (2.26%) patients had DTI. After AIC stepwise analysis, ULBT, MMT, sex, TMJ, age, BMI, TMD, IID, and TT were integrated for DL nomogram; ULBT, TMJ, age, IID, TT were integrated for DTI nomogram. The areas under the ROC curves were 0.933 [95% confidence interval (CI), 0.912–0.954] and 0.974 (95% CI, 0.954–0.995) for DL and DTI, respectively.ConclusionNomograms based on airway ultrasonography could be a reliable tool in predicting DA.Trial registrationChinese Clinical Trial Registry (No. ChiCTR-RCS-14004539), registered on 13th April 2014.

A Predictor of Difficult Airway: The Tasli Classification in Transnasal Flexible Laryngoscopy

IntroductionDifficult airway is defined as difficulty or failure in one or more steps in upper airway management. Evaluation of the upper airway with physical examination methods and endoscopic devices is crucial in predicting difficult airway. The aim of this study was to evaluate bedside tests, Cormack Lehane (CL) and Tasli Classification (TC) scores of the patients and it was aimed to reveal the role of TC which will be performed preoperatively as a predictor of difficult tracheal intubation (DTI). MethodsThe study included a total of 98 patients who underwent surgical treatment under general anesthesia. Demographic data, including age, gender, and body mass index (BMI), and bedside tests consisting Modified Mallampati Classification (MMC), thyromental (TD) and sternomental (SD) distances, neck circumference (NC), interincisor distance (IID), CL and TC were recorded. ResultsEvaluation was made of 64 (65.3%) male and 34 (34.7%) female patients ranging in age from 18 to 84 years (mean age: 50.35 ± 0.47 years). The successfully intubated patients (SIP) group comprised 68 (69.4%) patients, and the difficult intubation patients (DIP) group, 30 (30.6%). According to CL, the numbers of SIP and DIP constituting grade 1 was 29 (42.6%) and one (3.3%); grade 2a was 29 (42.6%) and one (3.3%); grade 2b was eight (11.8%) and three (10%); grade 3a was one (1.5%) and six (20%); grade 3b was one (1.5%) and 14 (46.7%) respectively. Grade 4 was only detected in the DIP group in 5 (16.7%) patients. According to TC, the numbers of SIP and DIP constituting grade 1 was 20 (29.4%) and 1 (3.3%); grade 2a was 37 (54.4%) and seven (23.3%); grade 2b was 10 (14.7%) and 18 (60%); grade 3 was one (1.5%) and two (6.7%) respectively. Grade 4 was only detected in the DIP group in two (6.7%) patients. ConclusionThe TC, CL, NC and BMI scores were higher in the DIP group and higher TC scores (grade 2b, 3, and 4) can be a predictor of difficult airway. However, it may be more beneficial to use TC as a complementary diagnostic tool with bedside tests such as NC, SM, TM and MMC, rather than used alone.

Prediction of Difficult Tracheal Intubation by Artificial Intelligence: A Prospective Observational Study

Aim: Many predictive clinical tests are used together for preoperative detection of patients with difficult airway risk. In this study, we aimed to predict difficult intubation with different artificial intelligence algorithms using various clinical tests and anthropometric measurements, besides, to evaluate the accuracy performance of Cormack and Lehane (C-L) classification with artificial intelligence. Material and Methods: This study was conducted as a single-blind prospective observational study between 2016 and 2019. A total of 1486 patients with American Society of Anesthesiologists physical status I-III, scheduled to undergo elective surgery and requiring endotracheal intubation, were included. Demographic variables, clinical tests and anthropometric measurements of the patients were recorded. Difficult intubation was evaluated using the 4-grade C-L system according to the easy and difficult intubation criteria. Difficult intubation was tried to predict using 16 different artificial intelligence algorithms. Results: The highest success rate among artificial intelligence algorithms was obtained by the RandomForest method. With this method, difficult intubation was predicted with 92.85% sensitivity, 96.94% specificity, 93.69% positive predictive value and 96.52% negative predictive value. C-L classification accuracy performance also determined as 95.60%. Conclusion: Artificial intelligence has been considerably successful in predicting difficult intubation. Besides, C-L classifications of easy and difficult intubated patients were successfully predicted with artificial intelligence algorithms. Using a 6-grade modified C-L classification for laryngeal view may provide stronger difficult intubation prediction. A safer and more potent prediction in training artificial intelligence can be achieved by adding individual differences and clinical features that support the definition of difficult intubation.

Comparison of modified Mallampati grading in sitting and supine position to predict difficult intubation in acromegaly patients

BackgroundAcromegaly patients have a very high incidence of difficult endotracheal intubation. The Modified Mallampatti grading (MMPG) in the sitting position is a common test performed preoperatively to predict difficult intubation. It has been suggested that supine MMPG is possibly a better predictor of difficult tracheal intubation (DTI) rather than the sitting MMPG in normal individuals. ObjectiveWe wanted to determine if the supine MMPG had a better diagnostic accuracy than the sitting MMPG in predicting DTI in acromegaly patients. MethodsThis was a single-centre prospective observational study conducted in 70 adult acromegaly patients undergoing pituitary adenoma surgery requiring general anaesthesia and endotracheal intubation. MMPG in the sitting position was recorded during the pre-anaesthesia consultation. An independent observer recorded the MMPG in the supine position and the ease of intubation prior to surgery. The diagnostic performance of the MMPG for the prediction of DTI was evaluated in the sitting and supine positions through the area under the receiver operating characteristic (ROC) curve. The Naguib score was also calculated and its ability to predict DTI was tested. ResultsThirty-five patients (50%) out of a total of 70 patients had difficult tracheal intubation. The area under the ROC curve for MMPG in supine position 0.708 (0.587–0.810) was greater than that for the MMPG in the sitting position 0.616 (0.492–0.729) ; p = 0.0146∗). ConclusionMMPG performed in the supine position was possibly a superior predictor of difficult tracheal intubation in adult acromegaly patients compared with MMPG performed in the sitting position.

Predictors of difficult endotracheal intubation in the emergency department: a single-center pilot study

Background: Identifying patients who are at risk of difficult endotracheal intubation is crucial in the emergency department. Therefore, this study evaluated the incidence and predictive factors of difficult tracheal intubation in the emergency department. Methods: This was a 17-month prospective observational study. A difficult airway was defined as Cormack &amp; Lehane classification grades III and IV at the first attempt of intubation. Patients who visited the emergency department, underwent traditional endotracheal intubation from participating physicians, and provided informed consent by themselves or via their delegates were enrolled in this study. Univariate associations between patient characteristics and difficult endotracheal intubation were identified, and statistically significant factors were included in a multivariate binary logistic regression model. A generalized association plot was used to show the relationships between variables. Results: A total of 110 patients were enrolled in the study. The incidence of difficult intubation was 35.5% (39/110). In the difficult airway group, significantly higher body mass index (BMI), and incidence of double chin, thick short neck, Mallampati difficulty, small interincisor distance, small thyromental distance, and upper airway obstruction were noted on univariate analysis. A predictive formula for difficult tracheal intubation was successfully established by the combination of four independent predictors: BMI (odds ratio [OR] = 1.270), thyromental distance (OR = 0.614), upper airway obstruction (OR = 4.038), and Mallampati difficulty (OR = 5.163). A cutoff score of four maximized Youden’s index, providing sensitivity (79.5%) and specificity (81.7%) (95% CI: 0.794 to 0.938). Conclusions: We used four predictors of difficult tracheal intubation, namely, BMI, thyromental distance, upper airway obstruction, and Mallampati difficulty, to create a predictive formula. This formula could help emergency physicians to quickly identify and carefully manage patients with difficult endotracheal intubation and consult experts early if necessary.

Management of Difficult Tracheal Intubation: A Closed Claims Analysis.

Difficult or failed intubation is a major contributor to morbidity for patients and liability for anesthesiologists. Updated difficult airway management guidelines and incorporation of new airway devices into practice may have affected patient outcomes. The authors therefore compared recent malpractice claims related to difficult tracheal intubation to older claims using the Anesthesia Closed Claims Project database. Claims with difficult tracheal intubation as the primary damaging event occurring in the years 2000 to 2012 (n = 102) were compared to difficult tracheal intubation claims from 1993 to 1999 (n = 93). Difficult intubation claims from 2000 to 2012 were evaluated for preoperative predictors and appropriateness of airway management. Patients in 2000 to 2012 difficult intubation claims were sicker (78% American Society of Anesthesiologists [ASA] Physical Status III to V; n = 78 of 102) and had more emergency procedures (37%; n = 37 of 102) compared to patients in 1993 to 1999 claims (47% ASA Physical Status III to V; n = 36 of 93; P < 0.001 and 22% emergency; n = 19 of 93; P = 0.025). More difficult tracheal intubation events occurred in nonperioperative locations in 2000 to 2012 than 1993 to 1999 (23%; n = 23 of 102 vs. 10%; n = 10 of 93; P = 0.035). Outcomes differed between time periods (P < 0.001), with a higher proportion of death in 2000 to 2012 claims (73%; n = 74 of 102 vs. 42%; n = 39 of 93 in 1993 to 1999 claims; P < 0.001 adjusted for multiple testing). In 2000 to 2012 claims, preoperative predictors of difficult tracheal intubation were present in 76% (78 of 102). In the 97 claims with sufficient information for assessment, inappropriate airway management occurred in 73% (71 of 97; κ = 0.44 to 0.66). A "can't intubate, can't oxygenate" emergency occurred in 80 claims with delayed surgical airway in more than one third (39%; n = 31 of 80). Outcomes remained poor in recent malpractice claims related to difficult tracheal intubation. Inadequate airway planning and judgment errors were contributors to patient harm. Our results emphasize the need to improve both practitioner skills and systems response when difficult or failed tracheal intubation is encountered.

Predictors of Difficult Tracheal Intubation on Adult Elective Patients in a Teaching Hospital

Background: During routine preoperative assessment of patients one of the commonest practices is predicting difficulty of tracheal intubation from various factors detected. Whether the factors reliably predict the difficulty is subject of argument. This study was conducted to assess the predictors of difficult tracheal intubation in adult patients. Methods: In this prospective observational study, we studied 120 consecutive elective adult patients admitted for general, gynecologic and orthopedic surgeries. Socio-demographic parameters and test variables such as BMI, TMD, SMD, IIG and Mallampati class were collected during preoperative evaluation. CL grade and difficulty of intubation were observed while the anesthetist in duty performs the laryngoscopy. While the former obtained from the preoperative anesthesia note, the latter were filled to questionnaire based on what the anesthetist reports during or after laryngoscopy. The prevalence of difficult intubation and the sensitivity, specificity, PPV and NPV of the tests were analyzed. SPSS-20 and different formulas were used during analysis. Chi square test was used and P&lt;0.05 was considered as statistically significant. Result: The overall prevalence of difficult tracheal intubation was 2.5%. The sensitivity, specificity, PPV &amp; NPV of the tests were 0%, 98.3%, 0% &amp; 97.46% for BMI; 0%, 97.5%, 0% &amp; 100% for SMD; 100%, 96.64%, 20% &amp; 100% for TMD; 0%, 99.17%, 0%, &amp; 100% for IIG; and 100%, 99.14%, 75% &amp; 100% for Mallampati test. Conclusion: The incidence is not quite small that anesthetists should use necessary tests to predict the difficult intubation. Probably combining the tests being the best option, Mallampati test alone can predict the difficult intubation in adult patients.

BMI as a Predictor for Potential Difficult Tracheal Intubation in Males.

Difficult tracheal intubation is a common source of mortality and morbidity in surgical and critical care settings. The incidence reported of difficult tracheal intubation is 0.1%-13% and reaches 14% in the obese population. The objective of our retrospective study was to investigate and compare the utility of body mass index (BMI) as indicator of difficult tracheal intubation in males and females. We performed a retrospective chart review of patients who underwent abdominal surgeries with American Society of Anesthesiologists I to V under general anesthesia requiring endotracheal intubation. The following information was obtained from medical records for analysis: gender, age, height, weight, BMI, length of patient stay in the Post Anesthesia Care Unit, past medical history of sleep apnea, Mallampati score, and the American Society of Anesthesiologists classification assigned by the anesthesia care provider performing the endotracheal intubation. Of 4303 adult patients, 1970 (45.8%) men and 2333 (54.2%) women were enrolled in the study. Within this group, a total of 1673 (38.9%) patients were morbidly obese. The average age of the study group was 51.4 ± 15.8 and the average BMI was 29.7 ± 8.2 kg/m(2). The overall incidence of the encountered difficult intubations was 5.23% or 225 subjects. Thus, our results indicate that BMI is a reliable predictor of difficult tracheal intubation predominantly in the male population; another strong predictor, with a positive linear correlation, being the Mallampati score. In conclusion, our data shows that BMI is a reliable indicator of potential difficult tracheal intubation only in male surgical patients.

In Reply

We thank Dr. Knapp for highlighting our recent article on prediction of difficult tracheal intubation.1 We agree with his comments. Indeed, he raised two major issues: the first one is the lack of universal definition for difficult tracheal intubation and the second one is when such a difficulty has been predicted, it is not the end of the story based on anatomic thoughtfulness, but the beginning of solutions according to various strategies related to new devices such as videolaryngoscopes overcoming a difficult laryngoscopy with conventional direct laryngoscopy.Requirement of an alternate technique to conventional laryngoscopy seems an important way to define, even nowadays, a difficult airway. It means you overcome the difficulty with another device alone or in adjunct to the conventional laryngoscope. Nevertheless, you have already succeeded in performing tracheal intubation, but the “therapeutic pressure” was not the same. For example, in septic shock patients with the same mean arterial pressure of 65 mmHg, if in one case a norepinephrine support is 0.5 mg/h and in another case 5 mg/h for norepinephrine support, seriousness of these patients is obviously totally different.The main paradigm change in difficult tracheal prediction we tried to highlight in our article was to decrease the proportion of patients in the inconclusive zone (gray zone) to implement an optimized airway management strategy according to the patient’s risk, with the necessity or not to master a difficult tracheal intubation with an appropriate alternate technique to conventional laryngoscopy or to maintain this standard technique by excluding such a difficulty. This anticipated difficulty in a given patient is an a priori approach and is different from the one using an established algorithm to achieve successful tracheal intubation by incorporating various advanced airway devices due to conventional laryngoscopy failures.2 In this last feature, the approach was a posteriori, managing the difficulty when it occurred with a predefined procedure. But in both cases, it moves the lines from a static predicting failure model relying only on an anatomical model, i.e., Mallampati classification, to a dynamic success model with implementation of newer airway devices to overcome the difficult airway pushing the limits of difficult tracheal intubation definition. This was indeed the true paradigm change we emphasized.

Prediction of Difficult Tracheal Intubation

Background It has been suggested that predicting difficult tracheal intubation is useless because of the poor predictive capacity of individual signs and scores. The authors tested the hypothesis that an accurate prediction of difficult tracheal intubation using simple clinical signs is possible using a computer-assist model. Methods In a cohort of 1,655 patients, the authors analyzed the predictive properties of each of the main signs (Mallampati score, mouth opening, thyromental distance, and body mass index) to predict difficult tracheal intubation. They built the best score possible using a simple logistic model (SCOREClinic) and compared it with the more recently described score in the literature (SCORENaguib). Then they used a boosted tree analysis to build the best score possible using computer-assisted calculation (SCOREComputer). Results Difficult tracheal intubation occurred in 101 patients (6.1%). The predictive properties of each sign remain low (maximum area under the receiver operating characteristic curve 0.70). Using receiver operating characteristic curve, the global prediction of the SCOREClinic (0.74, 95% CI: 0.72-0.76) was greater than that of the SCORENaguib (0.66, 95% CI: 0.60-0.72, P&amp;lt;0.001) but significantly lower than that of the SCOREComputer (0.86, 95% CI: 0.84-0.91, P&amp;lt;0.001). The proportion of patients in the inconclusive zone was 71% using SCORENaguib, 56% using SCOREClinic, and only 32 % using SCOREComputer (all P&amp;lt;0.001). Conclusion Computer-assisted models using complex interaction between variables enable an accurate prediction of difficult tracheal intubation with a low proportion of patients in the inconclusive zone. An external validation of the model is now required.

A Patient With Subcutaneous Emphysema Following Endotracheal Intubation

Difficult intubation can be found in 11% of emergency tracheal intubations.[1][1] Predictors of difficult tracheal intubation have been described, such as mouth opening, Mallampati classification, atlanto-occipital joint extension, mandibulohyoid distance, inter-incisor distance, thyromental

Gestion des voies aériennes en obstétrique

ObjectiveReviewing problems related to the airway management in obstetrics, taking into account the recent evolutions of the anaesthetic practices in obstetrics. Data sourcesA review of the literature in English and French was performed in the Pumed® database in April 2010. The first research used the following MeshTerms: “Anesthesia, Obstetrical” [Mesh] AND “Intubation, Intratracheal” [Mesh]. Complementary research used alone or in combination the following keywords: difficult tracheal intubation; failed tracheal intubation; airway; prediction of difficult tracheal intubation; maternal mortality; maternal morbidity; liability; aspiration pneumonia and obstetrical anesthesia. Study selectionAll the publications were retained excluding the correspondence. Data extractionData analysis for the airway management in obstetrics, the prediction of difficult intubation, the prevention of pulmonary inhalation of gastric fluid, but also on maternal morbi-mortality in link with general anesthesia in obstetrics. Data synthesisAirway management in obstetrics remains a true challenge for various reasons. The physiological and anatomical modifications related to pregnancy are responsible for a faster hypoxemia, a reduction of the diameter of the pharyngolaryngal tract, as well as an increase of the risk of inhalation of gastric contents after 16 weeks of amenorrhea. The emergency or extreme emergency context and the presence of diseases like obesity or preeclampsia raise the risks of difficulties with airway management. The logical evolution of the practices, with the considerable rise of the regional anesthesia/analgesia limits the training and the maintenance of competences for intratracheal intubation in obstetrics. The training per simulation appears particularly interesting on the subject and this approach needs to be developed. The literature indicates that the incidence of difficult intubation is of one per 30. The impossible intubation is one per 280 in obstetrics, eight times greater than in the general population. No criterion of difficult intubation is sufficiently predictive alone. In obstetrics as in other contexts, the association of several criteria will permit to anticipate a difficult intubation. There is a worsening of the Mallampati during the pregnancy and during labour. To limit the risk of a difficult management of the airway in obstetrics, it will be paramount and capital, in addition to give priority to the regional anaesthesia/analgesia each time possible, to perform a careful and repeated evaluation of the predictive criteria of difficult intubation or ventilation. The inhalation of gastric fluid will systematically be prevented. The adapted material and algorithms for difficult intubation must be available in the labour wards. In case of a difficult intubation during an emergency caesarean section, the SFAR algorithms must be applied. In case of a “cannot intubate can ventilate situation”, the possibility of carrying on the Caesarean maintaining the Sellick manoeuvre should be considered. The place of the laryngoscopy assisted by videolaryngoscope in this context clearly remains to be defined. Even if in the literature some cases of successful intubation through these devices suggest an interest, there is a clear deviance between the guidelines and the practices concerning general anaesthesia performed at the end of the labour. Indeed they should be systematically performed with rapid sequence induction and tracheal intubation. A reflexion on this theme is necessary in order to grant the practices to the recommendations.

Tracheal Configuration as a Radiographic Predictor of Difficult Tracheal Intubation in Goiters

Background: Goiters producing tracheal deviation or tracheal narrowing (TN) or both may cause difficult tracheal intubation (DTI). This study is to determine whether pre-operative assessment of trachea on neck radiograph can serve to predict DTI in goiters Methods: Pre- thyroidectomy radiographs of 160 patients were retrospectively studied for tracheal narrowing and deviation. Patients’ clinical and surgical data including Anaesthesiologists’ documented intubation experiences were also evaluated. Tracheal narrowing and relative sizes of the goiter were assessed on frontal and lateral neck radiographs. . Goodman Kruskal Tau cross tabulation analysis with SPSS 11.0 for windows was used to correlate TN to Anaesthetists operative reports of ease or difficulty of intubation. Results: Coronal and sagittal tracheal diameters ranged between 3mm to 27mm. It was less than 7mm in one or both planes in 21 (13.2%) of patients and all had DTI, P = 0.019. The length of TN did not show significant statistical correlation to DTI, P = 0.791. The only two patients having coronal or sagittal tracheal diameter less than 5mm, had failed intubation and surgery was done using bilateral superficial cervical plexus block. Conclusions: Goiters producing luminal TN of less than 7mm have potential for DTI and failed intubation when less than 5mm. Key words: Goiter, Difficult intubation, plain radiograph, thyroidectomy, Trachea

Erratum to: Is the modified Mallampati test performed in supine position a reliable predictor of difficult tracheal intubation?

Erratum to: Is the modified Mallampati test performed in supine position a reliable predictor of difficult tracheal intubation?

In reply to comment on “Is the modified Mallampati test performed in supine position a reliable predictor of difficult tracheal intubation?”

The sensitivity of the modified Mallampati test (MMT) performed in the supine position is higher (69%) than for the MMT performed in sitting position (31%); whereas the specificity of the MMT in the supine and sitting positions is 61 and 84% respectively. Both tests are associated with comparable positive predictive values (23% for the sitting MMT and 21% for the supine MMT). The negative predictive value of the supine MMT is 93% compared 89% for the sitting MMT. The supine MMT is associated with high true positives (11 out of 123). The observation made by the authors is that the supine position is an equally good predictor of difficult intubation, because the positive predictive value of both positions is similar. The sitting MMT gives a more accurate negative predictive value. The data given in Table 1 stand the same and correctly predict the correlation between the two positions. We also confirm that the total number of patients is 123 and not 124. To conclude, the authors suggest that inability to perform the MMT in the sitting position should not raise concern because the test performed in the supine position gives comparable predictive results for airway assessment.