Objective To evaluate the changes in three-dimensional computer tomography (3DCT) images of upper airway in patients with difficult tracheal intubation and provide theoretical evidence for predicting the difficult tracheal intubation. Methods Seventeen ASA Ⅰ or Ⅱ male patients, 25-60 yr old, height 165-185 era, weight 55-110 kg, body mass index 19-33 kg/m2, scheduled for elective surgery under general anesthesia, were studied. The airway condition was evaluated with Mallampati classification and Willsan score system in all patients before the operation. The patients underwent 3DCT scanning under 2 different statuses: with or without tongue protruding while opening his mouth maximally. The volume of the oropharyngeal cavity (Va1, Va2) andtongue body (Vt1, Vt2), and area of the oropharyngeal cavity (Aa1, Aa2) and tongue body (At1, At2) in the coronal position were measured before and during tongue protruding. The midline sagittal images of the upper airway were made on computer to measure the direct laryngoscope angle and vertical distance between the mandible and hyoid (MHD). Awake blind tracheal intubation was performed in all patients. The exposure of the glottis was performed after anesthesia induction and evaluated with Cormack-Lehane classification. The patients were divided into non-difficult intubation group (group NDI, Cormack-Lehane grade Ⅰ or Ⅱ) and difficult intubation group (group DI, Cormack-Lehane grade Ⅲ or Ⅳ) according to Cormack-Lehane classification. Results There were 8 patients in group NDI, and 9 patients in group DI. There was no significant difference in the indices before tongue protruding between group DI and NDI (P>0.05). Va2, Va1 - Va1, Aa2, Aa1 - Aa2, and At1- At2 weresignificanfly smaller, MHD was significantly longer and Va1,/Vt1- Va2/Vt2was significantly larger in group DI than in group NDI (P < 0.05 or 0.01). Va2 and Aa2 were significantly smaller than Va1 and Aa1 in group DI respectively (P < 0.05). Conclusion The changes in 3DCT images of the upper airway in patients with difficult tracheal intubation are mainly presented as smaller volume and area of the oropharyngeal cavity, larger difference value of the ratio of cavity volume to tongue volume and prolonged MHD.

Since the outbreak of COVID-19, several prevention and control measures have been successively promulgated in Wuhan. To name a few, setup of designated hospitals for severe COVID-19 patients is key to enforcing the policy of pooling patients, experts, resources and standardizing treatment. These efforts contribute decisively to improving the cure rate and reducing the mortality of COVID-19. As one of the designated hospitals composed of multiple medical teams, Wuhan Union Hospital put in place a joint working mode for treating severe COVID-19 patients, and found solutions to the main problems and difficulties in management. Its experiences provide references for the operation of joint medical institutions in emergency.

BACKGROUNDMycoplasma pneumonia (M. pneumoniae) is one of the key pathogens of community-acquired pneumonia. A global pandemic of M. pneumoniae has occurred since 2010. The aim of this study was to survey the prevalence of M. pneumoniae in children in Beijing from 2007-2012.

METHODSA total of 3 073 clinical specimens were obtained from pediatric patients with respiratory tract infections from January 2007 to December 2012, and examined by nested polymerase chain reaction. PCR products were visualized by 2% agarose gel electrophoresis, positive products sequenced, and compared with reference sequences in GenBank. Macrolide resistance-associated mutations were also detected for some positive samples.

RESULTSOf the 3 073 specimens, 588 (19.13%) were positive for M. pneumoniae, 12.4% of which were accompanied by viral infections. Positive rates for M. pneumoniae were highest in 2007 and 2012, showing a significant difference when compared with other years. Infections tended to occur in autumn and winter and positive rates were significantly higher for children aged 3-16. The rate of macrolide resistance-associated mutations was 90.7%, and the predominant mutation was an A→G transition (89.92%) at position 2063 in domain V of the 23S rRNA gene.

CONCLUSIONSM. pneumoniae outbreaks occurred in 2007 and 2012 in pediatric patients in Beijing, which is consistent with the global prevalence of M. pneumoniae. M. pneumoniae can cause multi-system infections in children, and may be accompanied with viral infections. We determined that school-age children are more susceptible to this disease, particularly in autumn and winter. Gene mutations associated with macrolide resistance were very common in M. pneumoniae-positive specimens during this period in Beijing.

Adolescent ; Anti-Bacterial Agents ; therapeutic use ; Child ; Child, Preschool ; Drug Resistance, Bacterial ; Female ; Humans ; Macrolides ; therapeutic use ; Male ; Mycoplasma pneumoniae ; pathogenicity ; Pneumonia, Mycoplasma ; drug therapy ; epidemiology ; Prevalence