Upper airway obstruction assessment: Peak inspiratory flow and clinical COPD Questionnaire

Spirometry in laryngotracheal stenosis: a systematic review and meta-analysis

PURPOSE

This study aimed to assess the changes in spirometry parameters or indices after relieving laryngotracheal stenosis (LTS) in adult patients.

METHODS

A systematic review and meta-analysis of studies from PubMed, Scopus, Web of Science, Cochrane Library, and EBSCO databases was conducted for assessing changes in spirometry values after endoscopic balloon dilatation of LTS in adults. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Relevant data, such as changes in mean spirometry values between preoperative and postoperative interventions, and findings of receiver operating characteristic curve analyses for predicting the need for surgical intervention, were extracted.

RESULTS

Ten studies including 330 patients overall met the inclusion criteria. Significant improvements were observed from preoperative to postoperative mean values of different spirometry parameters and indices. The overall mean differences in peak expiratory flow (ΔPEF), expiratory disproportion index (ΔEDI), and peak inspiratory flow (ΔPIF) were 2.26 L/s (95% CI 2.14-2.38), 27.94 s (95% CI 26.36-29.52), and 1.21 L/s (95% CI 0.95-1.47), respectively. ΔPEF and ΔPIF values increased, while ΔEDI decreased. In predicting the need for surgical intervention, EDI had the highest sensitivity (88%), and forced expiratory volume per second/forced vital capacity had the highest specificity (85%).

CONCLUSION

Spirometry is a valuable tool for assessing patients with LTS. PEF, EDI, and PIF were the most commonly reported spirometry parameters that significantly improved after airway stenosis was relieved.

L-Arginine, as an essential amino acid, is a potential substitute for treating COPD via regulation of ROS/NLRP3/NF-κB signaling pathway

BACKGROUNDS

Chronic obstructive pulmonary disease (COPD) is a frequent and common disease in clinical respiratory medicine and its mechanism is unclear. The purpose of this study was to find the new biomarkers of COPD and elucidate its role in the pathogenesis of COPD. Analysis of metabolites in plasma of COPD patients were performed by ultra-high performance liquid chromatography (UPLC) and quadrupole time-of-flight mass spectrometry (TOF-MS). The differential metabolites were analyzed and identified by multivariate analysis between COPD patients and healthy people. The role and mechanisms of the differential biomarkers in COPD were verified with COPD rats, arginosuccinate synthetase 1 (ASS-l) KO mice and bronchial epithelial cells (BECs). Meanwhile, whether the differential biomarkers can be the potential treatment targets for COPD was also investigated. 85 differentials metabolites were identified between COPD patients and healthy people by metabonomic.

RESULTS

L-Arginine (LA) was the most obvious differential metabolite among the 85 metabolites. Compare with healthy people, the level of LA was markedly decreased in serum of COPD patients. It was found that LA had protective effects on COPD with in vivo and in vitro experiments. Silencing Ass-1, which regulates LA metabolism, and α-methy-DL-aspartic (NHLA), an Ass-1 inhibitor, canceled the protective effect of LA on COPD. The mechanism of LA in COPD was related to the inhibition of ROS/NLRP3/NF-κB signaling pathway. It was also found that exogenous LA significantly improved COPD via regulation of ROS/NLRP3/NF-κB signaling pathway. L-Arginine (LA) as a key metabolic marker is identified in COPD patients and has a protective effect on COPD via regulation of ROS/NLRP3/NF-κB signaling pathway.

CONCLUSION

LA may be a novel target for the treatment of COPD and also a potential substitute for treating COPD.

Feasibility of face mask spirometry during decannulation in head and neck surgery: prospective cohort study

OBJECTIVES

To analyze the relationship between spirometric parameters measured with a face mask versus a mouthpiece, as well as the feasibility of face mask spirometric evaluation in a head and neck surgery (HNS) decannulation context. Furthermore, we examine peak inspiratory flow (PIF) cut-off values before and after decannulation.

DESIGN

Prospective cohort study.

SETTING

Otolaryngology HNS Department of a University teaching hospital.

PARTICIPANTS

Twenty-four patients were selected. A maximal flow-volume loop was conducted before (with mouthpiece) and after (with mouthpiece and face mask) decannulation.

MAIN OUTCOME MEASURES

Recorded outcomes were forced vital capacity (FVC), forced expiratory volume in the first second, peak expiratory flow, PIF, forced expiratory flow at 50% of FVC and forced inspiratory flow at 50% of FVC. Spearman correlation coefficients between spirometric parameters measured with a face mask versus a mouthpiece were calculated. Wilcoxon test was used to check differences between mouthpiece and face mask values.

RESULTS

Correlation between mouthpiece and face mask spirometric values was moderate to high (r = 0.46 to 0.95). All parameters measured by spirometry were significantly lower with a face mask than those obtained with a mouthpiece (p < 0.05). Before decannulation, the lowest PIF value (tested with mouthpiece) that allowed successful decannulation was 1 L/s. After decannulation, the lowest PIF value tested with mouthpiece and face mask for successful completion of the decannulation process were 0.77 and 0.56 L/s, respectively.

CONCLUSION

Face mask is a feasible option to perform a spirometry when face diseases hinder spirometric evaluation through a mouthpiece in an HNC surgery context.

Assessment of peak inspiratory flow in the management of acute inspiratory dyspnoea

PURPOSE

Assessment of inspiratory dyspnoea associated with upper airway obstruction is based on subjective clinical and nasal fibreoptic laryngoscopy (NFL) signs. The aim of this study was to determine whether peak inspiratory flow (PIF) measurement could indicate the need for upper airway release surgery in patients with acute inspiratory dyspnoea during emergency.

METHODS

A retrospective single-institution study (February 2018-March 2020) of 48 patients with acute inspiratory dyspnoea and PIF measurement (Peak Flow In-Check Dial G16^®-Harlow-England) was conducted. The surgical decision was based on the clinical evaluation of the patient's respiratory tolerance and NFL.

RESULTS

Forty-eight patients were included in this study. Thirty-five patients underwent surgery (PIF: 36 L/min), and 13 patients did not (PIF: 58 L/min) (p = 0.0009). Three of these 13 patients underwent an operation later (PIF value: 42 L/min versus 63 L/min for the 10 others [p = 0.25]).

CONCLUSION

PIF measurement is a quantitative, objective, inexpensive, non-invasive, and quick test that is potentially useful for general practitioners, mobile medical teams, or for ear-nose-and-throat specialists. A threshold of 42 L/min can help doctors in emergency decision making to refer patients to an ear-nose-and-throat specialist to release the upper airway and perform surgery or to choose medical monitoring for patients with emergency inspiratory dyspnoea.