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.

Development and validation of a screening method for difficult tracheal intubation based on geometric simulation and computer technology.

BACKGROUND: The anatomical characteristics of difficult airways can be analysed geometrically. This study aims to develop and validate a geometry-assisted difficult airway screening method (GADAS method) for difficult tracheal intubation. METHODS: In the GADAS method, a geometric simulated model was established based on computer graphics. According to the law of deformation of the upper airway on laryngoscopy, the expected visibility of the glottis was calculated to simulate the real visibility on laryngoscopy. Validation of the new method: Approved by the Ethics Committee of Yijishan Hospital of Wannan Medical College. Adult patients who needed tracheal intubation under general anaesthesia for elective surgery were enrolled. The data of patients were input into the computer software to calculate the expected visibility of the glottis. The results of tracheal intubation were recorded by anaesthesiologists. The primary observation outcome was the screening performance of the expected visibility of the glottis for difficult tracheal intubation. RESULTS: The geometric model and software of the GADAS method were successfully developed and are available for use. We successfully observed 2068 patients, of whom 56 patients had difficult intubation. The area under the receiver operating characteristic curve of low expected glottis visibility for predicting difficult laryngoscopy was 0.96 (95% confidence interval [CI]: 0.95-0.96). The sensitivity and specificity were 89.3% (95% CI: 78.1-96.0%) and 94.3% (95% CI: 93.2%-95.3), respectively. CONCLUSIONS: It is feasible to screen difficult-airway patients by applying computer techniques to simulate geometric changes in the upper airway.

Effects of Different Concentrations of Ropivacaine Lumbar Plexus-Sciatic Nerve Block on Recovery from Anesthesia, Postoperative Pain and Cognitive Function in Elderly Patients with Femoral Neck Fracture.

Objective: To investigate the effects of lumbar plexus-sciatic nerve block with different concentrations of ropivacaine on recovery from anesthesia, postoperative pain, and cognitive function in elderly patients with femoral neck fracture. Method: A total of 110 elderly patients with femoral neck fractures who were treated in our hospital from January 2020 to January 2022 were selected as the research objects. According to the concentration of ropivacaine, they were divided into low-, medium-, and high-concentration groups (concentrations of ropivacaine were 0.15%, 0.25%, and 0.40%, respectively), with 36, 37, and 37 cases, respectively. Extubation time, anesthesia recovery time, and hospitalization time were recorded. Cognitive symptoms were assessed by the spatial cognitive ability, working memory ability, simple computing ability, and picture recognition ability test. The pain degree of patients was assessed by visual analogue scale (VAS). The occurrence of adverse reactions in patients was recorded. Result: There was no significant difference in extubation time, anesthesia recovery time, and hospitalization time among the three groups (P > 0.05). The PCA time of the patients in the high-concentration group was significantly longer than that in the low- and medium-concentration groups. The dosage of sufentanil within 24 hours and total sufentanil in the high-concentration group were significantly lower than those in the low- and medium-concentration groups, and the dosage of sufentanil within 24 hours and total sufentanil in the medium-concentration group was significantly less than that in the low-concentration group (P < 0.05). The cognitive function score for each entry of the three groups 1 d after surgery was lower than that before surgery (P < 0.05); On the 1 day after operation, the cognitive function score for each entry of the patients in the low-concentration group was significantly higher than that in the middle- and high-concentration groups, and the cognitive function score for each entry in the middle-concentration group was significantly higher than that in the high-concentration group (P < 0.05). There was no significant difference in VAS scores between the three groups at 2 h and 8 h after surgery (P > 0.05); 16 h and 24 h after operation, the VAS score of patients in the high-concentration group was significantly lower than that in the low- and medium-concentration groups, and the VAS score in the medium-concentration group was significantly lower than that in the low-concentration ropivacaine group (P < 0.05). The incidence of adverse reactions in the high-concentration ropivacaine group was significantly higher than that in the low- and medium-concentration groups (P < 0.05). Conclusion: The middle concentration of ropivacaine has good analgesic and nerve block effects and has less influence on cognitive function and less adverse reactions in elderly patients.