Effect of trans-nasal humidified rapid insufflation ventilatory exchange on reflux and microaspiration in patients undergoing laparoscopic cholecystectomy during induction of general anesthesia: a randomized controlled trial

Effectiveness of preoxygenation strategies: a systematic review and network meta-analysis

BACKGROUND

Preoxygenation is universally recommended before induction of general anaesthesia to prolong safe apnoea time. The optimal technique for preoxygenation is unclear. We conducted a systematic review to determine the preoxygenation technique associated with the greatest effectiveness in adult patients having general anaesthesia.

METHODS

We searched six databases for randomised controlled trials of patients aged ≥16 yr, receiving general anaesthesia in any setting and comparing different preoxygenation techniques and methods. Our primary effectiveness outcome was safe apnoea time, and secondary outcomes included incidence of arterial oxygen desaturation; lowest SpO2 during airway management; time to end-tidal oxygen concentration of 90%; and [Formula: see text] and [Formula: see text] at the end of preoxygenation. We assessed the quality of evidence according to Grading of Recommendations, Assessment, Development and Evaluation (GRADE) recommendations.

RESULTS

We included 52 studies of 3914 patients. High-flow nasal oxygen with patients in a head-up position was most likely to be associated with a prolonged safe apnoea time when compared with other strategies, with a mean difference (95% credible interval) of 291 (138-456) s and 203 (79-343) s compared with preoxygenation with a facemask in the supine and head-up positions, respectively. Subgroup analysis of studies without apnoeic oxygenation also showed high-flow nasal oxygen in the head-up position as the highest ranked technique, with a statistically significantly delayed mean difference (95% credible interval) safe apnoea time compared with facemask in supine and head-up positions of 222 (63-378) s and 139 (15-262) s, respectively. High-flow nasal oxygen was also the highest ranked technique for increased [Formula: see text] at the end of preoxygenation. However, the incidence of arterial desaturation was less likely to occur when a facemask with pressure support was used compared with other techniques, and [Formula: see text] was most likely to be lowest when preoxygenation took place with patients deep breathing in a supine position.

CONCLUSIONS

Preoxygenation of adults before induction of general anaesthesia was most effective in terms of safe apnoea time when performed with high-flow nasal oxygen with patients in the head-up position in comparison with facemask alone. Also, high-flow nasal oxygen in the head-up position is likely to be the most effective technique to prolong safe apnoea time among those evaluated. Clinicians should consider this technique and patient position in routine practice.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO CRD42022326046.

Yanghe Pingchuan granules mitigates oxidative stress and inflammation in a bronchial asthma rat model: role of the IKK/IκB/NF-κB signalling pathway

Background

Bronchial asthma (BA) is a chronic inflammatory airway disease. Previous research has shown that Yanghe Pingchuan granules (YPG), among the granules formulated by the First Affiliated Hospital of the Anhui University of Chinese Medicine, exerts a precise therapeutic effect on BA. We previously showed that YPG improves airway inflammation in BA rats. Other studies have shown that the inhibitor of kappa-B kinase (IKK)/inhibitor of NF-κB (IκB)/nuclear factor kappa-B (NF-κB) signalling pathway plays a key role in inflammation mediation. Therefore, this study explored whether YPG could intervene in BA through the IKK/IκB/NF-κB signalling pathway.

Methods

Ovalbumin-induced method was used to established BA rat model. After successful modelling, the authors used YPG to intervene the rats in BA rats. Hematoxylin-eosin (HE) staining was used to detect the bronchial pathological changes in BA rats, enzyme-linked immunosorbent assay (ELISA) was used to detect the changes of inflammatory factors (IL-1β and IL-6) and oxidative stress indexes malondialdehyde (MDA), superoxide dismutase (SOD) and nitrogen monoxide (NO), Quantitative real-time polymerase chain reactionCR and western blot were used to detect the expression of IKK/IκB/NF-κB signalling pathway.

Results

In BA model rats, YPG significantly improved the inflammatory response in bronchial tissues, reduced inflammatory factors IL-1β and IL-6, alleviated oxidative stress, reduced MDA and NO, and increased SOD. Quantitative real-time polymerase chain reaction and western blot results showed that YPG could block the IKK/IκB/NF-κB signalling pathway.

Conclusion

These findings showed that YPG had a definite therapeutic effect on BA, which may be related to blocking the IKK/IκB/NF-κB signalling pathway and improving inflammation and oxidative stress.