Preoperative airway assessment help anticipate a difficult airway. We hypothesized that a close association existed between difficult laryngoscopy and the neck circumference/inter-incisor gap ratio (RNIIG). Our aim was to determine its utility in predicting difficult laryngoscopy in cervical spondylosis patients. Two hundred thirteen consecutive patients, aged 20–70 years, scheduled to undergo cervical spine surgery under general anesthesia, were recruited. Preoperative assessments included inter-incisor gap (IIG), thyromental distance (TMD), neck circumference (NC), NC/IIG ratio (RNIIG), NC/TMD ratio (RNTMD) and modified Mallampati test (MMT). Cormack–Lehane scales were assessed during intubation. The anesthesiologist was blinded to the airway assessments. RNIIG’s ability to predict difficult laryngoscopy was compared with that of established predictors. Difficult laryngoscopy incidence was 16.4%. Univariate analysis showed that male gender, increased age, weight, NC, RNIIG and RNTMD, decreased IIG and TMD, and MMT 3 and 4 were associated with difficult laryngoscopy. Binary multivariate logistic regression analyses identified only one factor that was independently associated with difficult laryngoscopy: RNIIG. The odds ratio and 95% confidence interval (95% CI) were 1.932 (1.504–2.482). RNIIG (≥9.5) exhibited the largest area under the curve (0.80; 95% CI 0.73–0.86) and the highest sensitivity (88.6%; 95% CI 78.1–99.1) and negative predictive value (96.6%; 95% CI 94.0–99.2), confirming its better predictive ability. RNIIG is a new and simple predictor with a higher level of efficacy, and could help anesthetists plan for difficult laryngoscopy management in cervical spondylosis patients. ChiCTR-OON-16008320 (April 19th, 2016).

The purpose of this study was to compare the efficacy and safety of dexmedetomidine versus remifentanil for sedation during awake intubation using a Shikani optical stylet (SOS). Sixty-eight patients with cervical trauma or severe cervical spondylosis undergoing cervical spinal surgery were enrolled in this prospective study. They were randomly assigned to receive dexmedetomidine (Group D) or remifentanil (Group R). In Group D, the patients received an intravenous loading dose of dexmedetomidine 1 μg · kg−1 over 10 min followed by a continuous infusion of 0.7 μg · kg−1 · h−1. In Group R, a target-controlled infusion of remifentanil was administered to achieve a plasma concentration of 2.5 ng · ml−1, increased to 3 ng · ml−1 10 min later. An endotracheal tube was inserted using a SOS under dexmedetomidine or remifentanil sedation after topical anesthesia to the airway. Midazolam was given as rescue sedation. We recorded the first attempt intubation success rate, the dose of midazolam, duration of intubation, Ramsay Sedation Scale (RSS) score, tracheal tube tolerance score, duration of drug infusion, adverse events and patient satisfaction score. The RSS score was significantly higher in Group D than in Group R. First attempt success rate, rescue midazolam dose and the duration of intubation did not differ between the groups. Patients in Group R were significantly more tolerant of the tracheal tube. The incidence of hypoxia was significantly higher in Group R than Group D, but there was no significant difference in the incidence of other adverse events between the groups. The hemodynamic responses of the two groups were similar, but more patients in Group R were able to recall airway instrumentation. Both dexmedetomidine and remifentanil are effective sedatives for awake intubation using an SOS. Although the first attempt success rates were similar, patients sedated with remifentanil tolerated the tracheal tube better after intubation with moderately increased risk of desaturation. www.chictr.org.cn ; ChiCTR-TRC-13003052 (February 4th, 2013).

The effects of the intravenous anesthetics propofol and etomidate on circulation are significantly different; however, their differing effects on miRNA expression in the cardiovascular system are not clearly understood. The purpose of this study is to investigate the effects of these two anesthetics on miRNA expression profiles in the heart and blood vessels. Rats were randomly divided into a propofol group and an etomidate group. Spontaneous breathing was maintained throughout the anesthesia process and the rats’ oxygen supply was ensured. Heart and thoracic aorta tissue was harvested 3 h after induction. The expression profiles of cardiovascular miRNAs were detected by microarray 4.0 analysis. Twelve representative miRNAs were selected for qRT-PCR validation, and their target genes were predicted using bioinformatics methods. Microarray analysis showed 16 differentially expressed miRNAs in heart tissue from the propofol group compared with the etomidate group (10 up-regulated and 6 down-regulated), while in the blood vessels there were 25 altered miRNAs (10 up-regulated, 15 down-regulated). After verifying 12 representative miRNAs via qRT-PCR, the results showed no significant difference in the expression of miRNAs in the heart tissue, but a significant difference in the expression of 5 miRNAs in vessel tissue between the two groups. Bioinformatics analysis predicts that the target genes of the 5 differentially expressed miRNAs are associated with chemical synapse signaling pathways. Propofol and etomidate have different effects on the expression of cardiovascular miRNAs, and further research is needed to elucidate the functional consequences of these differentially expressed miRNAs.