Acid-base balance, serum electrolytes and need for non-invasive ventilation in patients with hypercapnic acute exacerbation of chronic obstructive pulmonary disease admitted to an internal medicine ward

A Clinical Score for Predicting Successful Weaning from Noninvasive Positive Pressure Ventilation in Emergency Department; a Retrospective Cohort Study

Introduction

Noninvasive positive pressure ventilation (NIPPV) is recognized as an efficient treatment for patients with acute respiratory failure (ARF) in emergency department (ED). This study aimed to develop a scoring system for predicting successful weaning from NIPPV in patients with ARF.

Methods

In this retrospective cohort study patients with ARF who received NIPPV in the ED of Ramathibodi Hospital, Thailand, between January 2020 and March 2022 were evaluated. Factors associated with weaning from NIPPV were recorded and compared between cases with and without successful weaning from NIPPV. Multivariable logistic regression analysis was used to develop a predictive model for weaning from NIPPV in ED.

Results

A total of 494 eligible patients were treated with NIPPV of whom 203(41.1%) were successfully weaned during the study period. Based on the multivariate analysis the successful NIPPV weaning (SNOW) score was designed with six factors before discontinuation: respiratory rate, heart rate ≤ 100 bpm, systolic blood pressure ≥ 100 mmHg, arterial pH≥ 7.35, arterial PaCO2, and arterial lactate. The scores were classified into three groups: low, moderate, and high. A score of >14.5 points suggested a high probability of successful weaning from NIPPV with a positive likelihood ratio of 3.58 (95%CI: 2.56-4.99; p < 0.001). The area under the receiver operating characteristic (ROC) curve of the model in predicting successful weaning was 0.79 (95% confidence interval (CI): 0.75-0.83).

Conclusion

It seems that the SNOW score could be considered as a helpful tool for predicting successful weaning from NIPPV in ED patients with ARF. A high predictive score, particularly one that exceeds 14.5, strongly suggests a high likelihood of successful weaning from NIPPV.

Early detection of non-invasive ventilation failure among acute respiratory failure patients in the emergency department

Background

Non-invasive mechanical ventilation (NIV) has become an alternative to an invasive artificial airway for the management of acute respiratory failure (ARF). NIV failure causes delayed intubation, which eventually has been associated with increased morbidity and mortality. This study aimed to develop the clinical scoring system of NIV failure in ARF patients.

Methods

This study was a diagnostic, retrospectively cross-sectional, and exploratory model at the Emergency Medicine Department in Ramathibodi Hospital between February 2017 and December 2017. We included all of the acute respiratory failure patients aged > 18 years and received non-invasive ventilation (NIV). Clinical factors associated with NIV failure were recorded. The predictive model and prediction score for NIV failure were developed by multivariable logistic regression analysis.

Result

A total of 329 acute respiratory failure patients have received NIV success (N = 237) and failure (N = 92). This study showed that NIV failure was associated with heart rate >  110 bpm, systolic BP <  110 mmHg, SpO2 < 90%, arterial pH < 7.30 and serum lactate. The clinical scores were classified into three groups: low, moderate, and high.

Conclusion

We suggested that the novel clinical scoring of the NIV failure in this study may use as a good predictor for NIV failure in the emergency room.

Aspects extrapulmonaires des exacerbations de bronchopneumopathie chronique obstructive

La bronchopneumopathie chronique obstructive (BPCO) est une maladie systémique aux multiples atteintes, émaillée d’exacerbations. L’inflammation, l’hypoxémie, les troubles de la coagulation et les perturbations des interactions coeur–poumon expliquent en partie les atteintes non pulmonaires observées notamment lors d’exacerbations aiguës. Les événements cardiovasculaires sont la première cause de mortalité des patients BPCO, et leur recrudescence est observée pendant plusieurs semaines après une exacerbation. Aux urgences, la prise en charge des patients en exacerbation de BPCO repose donc en plus du support ventilatoire sur une bonne évaluation des potentielles pathologies associées telles que l’insuffisance cardiaque, l’ischémie myocardique, l’insuffisance rénale ou encore la maladie thromboembolique. Cette évaluation globale permet d’adapter les thérapeutiques parfois délétères sur la fonction cardiaque ou l’équilibre acide−base et de prendre en compte le risque extrapulmonaire dans le choix du parcours de soins du patient. Dans cette mise au point, nous abordons quelques explications physiologiques des multiples perturbations observées au cours de l’exacerbation de BPCO, et proposons une vision globale de l’évaluation de ces patients admis pour une dyspnée ou un autre motif pouvant être en rapport avec la BPCO.

Deterioration of Limb Muscle Function during Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Important features of both stable and acute exacerbation of chronic obstructive pulmonary disease (COPD) are skeletal muscle weakness and wasting. Limb muscle dysfunction during an exacerbation has been linked to various adverse outcomes, including prolonged hospitalization, readmission, and mortality. The contributing factors leading to muscle dysfunction are similar to those seen in stable COPD: disuse, nutrition/energy balance, hypercapnia, hypoxemia, electrolyte derangements, inflammation, and drugs (i.e., glucocorticoids). These factors may be the trigger for a downstream cascade of local inflammatory changes, pathway process alterations, and structural degradation. Ultimately, the clinical effects can be wide ranging and include reduced limb muscle strength. Current therapies, such as pulmonary/physical rehabilitation, have limited impact because of low participation rates. Recently, novel drugs have been developed in similar disorders, and learnings from these studies can be used as a foundation to facilitate discovery in patients hospitalized with a COPD exacerbation. Nevertheless, investigators should approach this patient population with knowledge of the limitations of each intervention. In this Concise Clinical Review, we provide an overview of acute muscle dysfunction in patients hospitalized with acute exacerbation of COPD and a strategic approach to drug development in this setting.

Combined effects of lung function, blood gases and kidney function on the exacerbation risk in stable COPD: Results from the COSYCONET cohort

RATIONALE

Alterations of acid-base metabolism are an important outcome predictor in acute exacerbations of COPD, whereas sufficient metabolic compensation and adequate renal function are associated with decreased mortality. In stable COPD there is, however, only limited information on the combined role of acid-base balance, blood gases, renal and respiratory function on exacerbation risk grading.

METHODS

We used baseline data of the COPD cohort COSYCONET, applying linear and logistic regression analyses, the results of which were implemented into a comprehensive structural equation model. As most informative parameters it comprised the estimated glomerular filtration rate (eGFR), lung function defined via forced expiratory volume in 1 s (FEV₁), intrathoracic gas volume (ITGV) and (diffusing capacity for carbon monoxide (DLCO), moreover arterial oxygen content (CaO₂), partial pressure of oxygen (PaCO₂), base exess (BE) and exacerbation risk according to GOLD criteria. All measures were adjusted for age, gender, body-mass index, the current smoking status and pack years.

RESULTS

1506 patients with stable COPD (GOLD grade 1-4; mean age 64.5 ± 8.1 y; mean FEV₁ 54 ± 18 %predicted, mean eGFR 82.3 ± 16.9 mL/min/1.73 m²) were included. BE was linked to eGFR, lung function and PaCO₂ and played a role as indirect predictor of exacerbation risk via these measures; moreover, eGFR was directly linked to exacerbation risk. These associations remained significant after taking into account medication (diuretics, oral and inhaled corticosteroids), whereby corticosteroids had effects on exacerbation risk and lung function, diuretics on eGFR, BE and lung function.

CONCLUSION

Even in stable COPD acid-base metabolism plays a key integrative role in COPD risk assessment despite rather small deviations from normality. It partially mediates the effects of impairments in kidney function, which are also directly linked to exacerbation risk.