Bronchoalveolar lavage causes decrease in PaO2, increase in (A-a) gradient value and bronchoconstriction in asthmatics

Association between increased mortality and bronchial fibroscopy in intensive care units and intermediate care units during COPD exacerbations: an analysis of the 2014 and 2015 National French Medical-based Information System Databases (PMSI)

Background

The course of chronic obstructive pulmonary disease (COPD) is punctuated by exacerbations, most often of infectious origin, responsible for many intensive care unit (ICU) and intermediate care unit (IMCU) admissions. Our objective was to study in-hospital mortality during severe COPD exacerbations in ICU and IMCU based on the performance of bronchoscopy.

Methods

A retrospective analysis was carried out on stays in ICUs for COPD exacerbation from the French Programme for the Medicalisation of Information Systems databases for the years 2014 and 2015. Propensity score matching of stays made it possible to constitute two comparable groups on the factors of excess mortality described in the literature (age, sex, SAPS 2, type of admission and bronchial tumour).

Results

We identified 14,491 stays for COPD exacerbation in ICUs, 2586 of which received a bronchoscopy. Mortality was significantly higher in the fibroscopy group (31.32% versus 19.8%). After propensity score matching, we found an excess of mortality in the intervention group (OR = 1.749 [1.516–2.017]) associated with a significantly longer length of stay. The main diagnoses associated with an increased risk of death were pulmonary embolism (OR = 3.251 [1.126–9.384]), bacterial pneumonia (OR = 1.906 [1.173–3.098]) and acute respiratory failure (OR = 1.840 [1.486–2.278]).

Conclusions

Performing bronchoscopy during ICU hospitalisations for severe COPD exacerbations was associated with increased mortality. This increased mortality appears to be related to a bias in patient selection with a procedure reserved for patients with the adverse course.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40560-021-00560-w.

Is bronchodilator the correct treatment for COPD subjects before EBUS?

Endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) is a reliable and commonly established technique, enabling real-time guidance of transbronchial needle aspiration of mediastinal and hilar structures and parabronchial lung masses. As EBUS-TBNA became more available and adopted by clinicians, questions emerged about the optimal performance of the procedure. Although EBUS is considered safe, there are few complications that could occur during the test, correlated with both the procedure itself and the patient's characteristics. Moreover, this technique is often addressed to patients with overlapping airways diseases, which might have higher risk of complications during the procedure. Chronic obstructive pulmonary disease (COPD) patients could experience EBUS-TBNA with a relative high frequency due to their risk of developing lung cancer. The irreversible bronchial constriction characteristic of the disease raises some questions on premedication before bronchoscopic procedures. It is mandatory to optimize every aspect of the procedure in order to minimize the risk of complications, especially for fragile patients. Whether the use of inhaled bronchodilators before the procedure could improve the outcome of the procedure in COPD patients is reviewed in this article. No clear indication emerged from the literature suggesting the need of more studies in order to clarify this point.

Blood gas tensions in adult asthma: a systematic review and meta-regression analysis

OBJECTIVE

The last half-century has seen substantial changes in asthma treatment and care. We investigated whether arterial blood gas parameters in acute and non-acute asthma have changed historically.

METHODS

We performed a systematic search of the literature for studies reporting P(aO2) , P(aCO2) and forced expiratory volume in 1 s, percentage of predicted (FEV1%). For each of the blood gas parameters, meta-regression analyses examined its association with four background variables: the publication year, mean FEV1%, mean age and female fraction in the respective studies.

RESULTS

After screening, we included 43 articles comprising 61 datasets published between 1967 and 2013. In studies of habitual-state asthma, mean P(aO2) was positively associated with the publication year (p = 0.001) and negatively with mean age (p < 0.01). Mean P(aCO2) showed a positive association with publication year (p = 0.001) and a negative association with female fraction (p < 0.05). In acute asthma studies, blood gas levels were unassociated with publication year and mean age, mean P(aO2) was positively associated with FEV1% (p < 0.05) whereas mean P(aCO2) showed a negative association with FEV1% (p < 0.05) for studies with mean FEV1% <40. In neither acute nor habitual-state studies was mean arterial pH associated with any of the predictor variables.

CONCLUSIONS

In studies of habitual-state asthma, mean reported P(aO2) and P(aCO2) levels were found to have increased since 1967. In acute asthma studies, mean P(aO2) and P(aCO2) were associated with mean FEV1% but not with either publication year or patient age.

Non-invasive mechanical ventilation for diagnostic bronchoscopy using a new face mask: an observational feasibility study

Purpose

Bronchoscopy is an indispensable tool for invasive pulmonary evaluation with high diagnostic yield and low incidence of major complications. However, hypoxemia increases the risk of complications, in particular after bronchoalveolar lavage. Non-invasive positive pressure ventilation may prevent hypoxemia associated with bronchoalveolar lavage. The purpose of this study is to present a modified total face mask to aid bronchoscopy during non-invasive positive pressure ventilation.

Methods

A commercially available full face mask was modified to allow introduction of the bronchoscope without interfering with the ventilator circuit. Bronchoscopy with bronchoalveolar lavage was performed in 12 hypoxemic non-ICU patients during non-invasive positive pressure ventilation in the ICU.

Results

Patients had severely impaired oxygen uptake as indicated by PaO₂/FiO₂ ratio 192  ± 23 mmHg before bronchoscopy. Oxygenation improved after initiation of non-invasive positive pressure ventilation. In all patients the procedure could be completed without subsequent complications, although in one patient SpO₂ decreased until 86% during bronchoscopy. A microbiological diagnosis could be established in 8 of 12 patients with suspected for infection.

Conclusions

Our modified face mask for non-invasive positive pressure ventilation is a valuable tool to aid diagnostic bronchoscopy in hypoxemic patients.

A randomized, placebo-controlled trial of bronchodilators for bronchoscopy in patients with COPD

BACKGROUND

In contrast to asthma, the indication for bronchodilators prior to bronchoscopy in patients with COPD has not been properly investigated. We therefore performed a randomized, double-blind, placebo-controlled trial to determine whether use of a short-acting bronchodilator provides a protective effect in patients with COPD undergoing bronchoscopy.

METHODS

One hundred twenty patients undergoing bronchoscopy were included. Patients with COPD were randomized to receive either 200 mug of salbutamol (n = 40) or placebo (n = 40) before bronchoscopy. Control patients (n = 40) did not receive any inhaled medication. Spirometry was performed before and 2 h after bronchoscopy in all patients. Sedative drug requirements and hemodynamic parameters were recorded.

RESULTS

Hemodynamic findings before, during, and after bronchoscopy were similar in patients with COPD randomized to either salbutamol or placebo (p = not significant for all). Compared to prebronchoscopy values, postbronchoscopy percentage of predicted FEV(1) decreased significantly in all three groups: salbutamol (median, - 4.7%; interquartile range [IQR], - 13.3 to 6.6); placebo (median, - 4.8%; IQR, - 19.9 to 8.4); and control subjects (median, - 10.0%; IQR, - 20.2 to - 3.3) [p = 0.023]. The decrease in FEV(1) was similar in all three patient groups (p = 0.432). The relative change in FEV(1) was inversely correlated to the increasing severity of COPD as expressed by Global Initiative for Chronic Obstructive Lung Disease stages (p = 0.01).

CONCLUSIONS

Premedication with an inhaled short-acting beta-agonist cannot be recommended in patients with COPD undergoing bronchoscopy.

Functional implications of BAL in the presence of restrictive or obstructive lung disease

Most of the complications associated to bronchoscopy are related to changes of the respiratory function during or after its performance. Prevention of complications should be achieved by understanding the effects of bronchoscopic procedures and their relation to the pulmonary function deterioration. Previous studies regarding the functional impairment caused by bronchoalveolar lavage (BAL) were mostly limited by the presence of interferent factors such as sedative drugs. Furthermore, it is not clear whether or not patients with different ventilatory disturbances present the same functional response to bronchoscopy and BAL. The aim of this study was to determine the additional effects of BAL over the respiratory function deterioration related to bronchoscopy in patients with different respiratory function profiles (normal, restrictive and obstructive). Forty patients submitted to bronchoscopy without premedication were divided into four groups: group I-normal pulmonary function submitted to basic bronchoscopy; group II-bronchoscopy in combination with BAL, subdivided according to pulmonary function: group IIa (normal function), group IIb (restrictive ventilatory disturbances) and group IIc (obstructive ventilatory disturbances). Spirometry was made before and after the bronchoscopic procedure. Baseline hemoglobin saturation was compared to the lowest level during the procedure. Functional worsening caused by the procedure was observed with a decrease in forced vital capacity (FVC), forced expiratory volume in the first second (FEV(1)) and Hemoglobin saturation in all groups. Comparison between groups showed no significant difference regarding the changes in FVC (P=0.8324), FEV(1) (P=0.6952) and hemoglobin saturation (P=0.5044). We conclude that standardized BAL, like the one used in our study, does not result in an increased risk for ventilatory impairment compared to bronchoscopy itself, independently of the presence of previous respiratory disease.

Effect of body position on gas exchange after bronchoalveolar lavage

OBJECTIVE

To assess the possible influence of body position on oxygen saturation after bronchoscopy (BC) with bronchoalveolar lavage (BAL).

DESIGN

Prospective, open, randomized study.

SETTING

The respiratory unit of a first level, community hospital.

PATIENTS

Forty-one consecutive patients in which BC with BAL, using at least 150 mL of BAL fluid, was performed.

METHOD

We randomly assigned 21 patients to lie in lateral decubitus (LD) with the lung where BAL was performed uppermost after BC, and 20 to lie in supine position (SP). Oxygen saturation (SO2) was measured for all patients from 10 min before to 30 min after the end of the BC. Saturation parameters were compared for both groups.

RESULTS

Mean SO2 was significantly lower after than before the BC, both for LD and SP groups (LD: 91.4+/-3% vs. 94.9+/-2%, respectively; P=0.0001) (SP: 91.6+/-3 vs. 95.8+/-3%, respectively; P=0.0003). We did not find significant differences between LD and SP groups, after BC, regarding mean SO2 (91.4+/-3% vs. 91.6+/-3%), minimum SO2 (86.2+/-4.5% vs. 86.6+/-5.4%, respectively) or percentages of registry time at saturations below 90% (26.3+/-35.9% vs. 27.6+/-38.2%, respectively) (P:NS for all values).

CONCLUSION

BC with BAL caused significant oxygen desaturation in our patients. We have not been able to demonstrate a significant influence of body position on SO2 after BAL.

High fever after flexible bronchoscopy and bronchoalveolar lavage in noncritically ill immunocompetent children

Flexible bronchoscopy (FB) and bronchoalveolar lavage (BAL) have been applied increasingly to the evaluation of pulmonary disease in children. Although several complications have been reported following FB and BAL, high fever after BAL in immunocompetent children has not previously been reported. To determine the frequency, clinical characteristics, and outcome of these complications in children who developed high fever post-BAL, we retrospectively reviewed all bronchoscopic procedures done on an outpatient basis between August 1995 and July 1997. We identified 78 immunocompetent noncritically ill children who had undergone FB and BAL as an outpatient procedure for evaluation of underlying pulmonary disease, of whom 13 (17%) developed temperature (T) higher than or equal to 39 degrees C (fever group). The 13 patients in the fever group had a median age of 10 (range, 4-48) months and a reported T of 39.4 degrees C (39.1-40.6 degrees C) occurring 7.5 (4-12) hr after BAL. To determine if there were differences in clinical or BAL fluid (BALF) characteristics, we compared each child in the fever group to two children in the nonfever group, based upon primary indications and age. There were no differences in demographic or clinical characteristics between the two groups. Lymphocyte concentrations in BALF were significantly reduced in the fever group (P = 0.03). An abnormal BALF cell differential (defined as one or more of the following: neutrophils >10%, lymphocytes >30%, or eosinophils >1%) was significantly more common in the fever group (P = 0.008, odds ratio 3.6). We conclude that high fever is a frequent adverse event following BAL in noncritically ill immunocompetent children with underlying pulmonary disease. Pre-BAL clinical characteristics are not associated with development of high fever. However, the finding of an abnormal BALF cell differential is strongly associated with development of high fever post-BAL.