Non-invasive ventilation in cardiogenic pulmonary edema

Evaluation of HACOR scale as a predictor of non-invasive ventilation failure in acute cardiogenic pulmonary oedema patients: A prospective observational study

BACKGROUND AND IMPORTANCE

Acute cardiogenic pulmonary oedema (ACPO) is a common indication for non-invasive ventilation (NIV) in the emergency department (ED). HACOR score of >5 is used to predict NIV failure. The predictive ability of HACOR may be affected by altered physiological parameters in ACPO patients due to medications or comorbidities.

OBJECTIVES

To validate the HACOR scale in predicting NIV failure among acute cardiogenic pulmonary oedema (ACPO) patients.

DESIGN, SETTINGS AND PARTICIPANTS

This is a prospective, observational study of consecutive ACPO patients requiring NIV admitted to the ED.

OUTCOME MEASURE AND ANALYSIS

Primary outcome was the ability of the HACOR score to predict NIV failure. Clinical, physiological, and HACOR score at baseline and at 1 h, 12 h and 24 h were analysed. Other potential predictors were assessed as secondary outcomes.

MAIN RESULTS

A total of 221 patients were included in the analysis. Fifty-four (24.4%) had NIV failure. Optimal HACOR score was >5 at 1 h after NIV initiation in predicting NIV failure (AUC 0.73, sensitivity 53.7%, specificity 83.2%). As part of the HACOR score, respiratory rate and heart rate were not found to be significant predictors. Other significant predictors of NIV failure in ACPO patients were acute coronary syndrome, acute kidney injury, presence of congestive heart failure as a comorbid, and the ROX index.

CONCLUSIONS

The HACOR scale measured at 1 h after NIV initiation predicts NIV failure among ACPO patients with acceptable accuracy. The cut-off level > 5 could be a useful clinical decision support tool in ACPO patient. However, clinicians should consider other factors such as the acute coronary and acute kidney diagnosis at presentation, presence of underlying congestive heart failure and the ROX index when clinically deciding on timely invasive mechanical ventilation.

Noninvasive respiratory support in the emergency department: Controversies and state-of-the-art recommendations

Acute respiratory failure is a common reason for emergency department visits and hospital admissions. Diverse underlying physiologic abnormalities lead to unique aspects about the most common causes of acute respiratory failure: acute decompensated heart failure, acute exacerbation of chronic obstructive pulmonary disease, and acute de novo hypoxemic respiratory failure. Noninvasive respiratory support strategies are increasingly used methods to support work of breathing and improve gas exchange abnormalities to improve outcomes relative to conventional oxygen therapy or invasive mechanical ventilation. Noninvasive respiratory support includes noninvasive positive pressure ventilation and nasal high flow, each with unique physiologic mechanisms. This paper will review the physiology of respiratory failure and noninvasive respiratory support modalities and offer data and guideline-driven recommendations in the context of key clinical controversies.

Efficacy of BAINS Circuit in Treating Critically Ill Hypoxemic COVID-19 Patients During the Second Wave of the Pandemic in India

BACKGROUND

The COVID-19 pandemic has encouraged doctors to look for novel ways of treating patients with respiratory failure due to the limited availability of ventilators and highflow nasal cannula. The study aims to assess the efficacy of using the Bains circuit as an alternative to HFNC and NIV as life-saving tools in patients with respiratory failure during the second wave of the COVID-19 pandemic in India.

METHODS

This is a prospective interventional study carried out in the intensive care unit of Shri B.M Patil Medical College Hospital and Research Centre, Vijayapur, India, from May 2021 to June 2021. All patients (n=90) with respiratory failure not responding to therapy with an oxygen mask were included. Patients were placed on Bain circuits, one end connected to a non-invasive ventilation mask fitted to the face of the patients, and the other end connected to a central oxygen port. Patients' vital parameters were assessed on an hourly basis. The blood gas analyses were done before and after using Bains.

RESULTS

The study showed diabetes (33.4%), hypertension (22.2%), and diabetes with hypertension (11.1%) as comorbid factors among the ICU admitted patients. The results from the arterial blood gas analyses showed a statistically significant increase in Sp02 (%) and a decrease in respiratory rate (cycles/min) in the patients after being kept on Bains (p<0.05). Further, it showed that 72% of ICU patients with 70-79% Sp02 had a recovery by using Bains. The overall outcome of ICU admitted COVID-19 patients on Bains showed that 38.9% of patients improved and were shifted to 02/NRBM masks.

CONCLUSION

The study highlights a novel concept of using the Bains circuit as an effective alternative to HFNC and NIV for oxygenation in critically ill COVID-19 patients during scarcity of NIV and HFNC at the peak of the pandemic.

“The role of a negative pressure ventilator coupled with oxygen helmet against COVID-19: a review”

Background

The coronavirus (SARS-COV-2) pandemic has provoked the global healthcare industry by potentially affecting more than 20 14 million people across the globe, causing lasting damage to the lungs, notably pneumonia, ARDS (acute respiratory distress 15 syndrome), and sepsis with the rapid spread of infection. To aid the functioning of the lungs and to maintain the blood oxygen 16 saturation (SpO₂) in coronavirus patients, ventilator assistance is required.

Materials and methods

The main purpose of this article is to outline the need 17 for the introduction of a non-invasive negative pressure ventilator (NINPV) as a promising alternative to positive pressure 18 ventilator (PPV) by elucidating the cons of non-invasive ventilators in clinical conditions like ARDS. Another motive is to 19 profoundly diminish the rate of infection spread by the employment of oxygen helmets, instead of endotracheal intubation in 20 invasive positive pressure ventilator (IPPV) or non-invasive positive pressure ventilator (NIPPV) like face masks and high-flow 21 nasal cannula (HFNC).

Result and conclusion

The integration of oxygen helmet with NPV would result in a number of notable facets including the 22 degree of comfort delivered to patients who are exposed to various ventilator-induced lung injuries (VILI) in the forms of 23 atelectasis, barotrauma, etc. Likewise, preventing the aerosol-generating procedures (AGP) diminishes the rate of nosocomial 24 infections and providing a better environment to both the patients and the healthcare professionals.

Dyspnea

The clinical term dyspnea (a.k.a. breathlessness or shortness of breath) encompasses at least three qualitatively distinct sensations that warn of threats to breathing: air hunger, effort to breathe, and chest tightness. Air hunger is a primal homeostatic warning signal of insufficient alveolar ventilation that can produce fear and anxiety and severely impacts the lives of patients with cardiopulmonary, neuromuscular, psychological, and end-stage disease. The sense of effort to breathe informs of increased respiratory muscle activity and warns of potential impediments to breathing. Most frequently associated with bronchoconstriction, chest tightness may warn of airway inflammation and constriction through activation of airway sensory nerves. This chapter reviews human and functional brain imaging studies with comparison to pertinent neurorespiratory studies in animals to propose the interoceptive networks underlying each sensation. The neural origins of their distinct sensory and affective dimensions are discussed, and areas for future research are proposed. Despite dyspnea's clinical prevalence and impact, management of dyspnea languishes decades behind the treatment of pain. The neurophysiological bases of current therapeutic approaches are reviewed; however, a better understanding of the neural mechanisms of dyspnea may lead to development of novel therapies and improved patient care.

Remifentanil versus dexmedetomidine for treatment of cardiac surgery patients with moderate to severe noninvasive ventilation intolerance (REDNIVIN): a prospective, cohort study

BACKGROUND

The use of sedation to noninvasive ventilation (NIV) patients remains controversial, however, for intolerant patients who are uncooperative, administration of analgesics and sedatives may be beneficial before resorting to intubation. The aim of this study was to evaluate the efficacy of remifentanil (REM) versus dexmedetomidine (DEX) for treatment of cardiac surgery (CS) patients with moderate to severe NIV intolerance.

METHODS

This prospective cohort study of CS patients with moderate to severe NIV intolerance was conducted between January 2018 and March 2019. Patients were treated with either REM or DEX, decided by the bedside intensivist. Depending on the treatment regimen, the patients were allocated to one of two groups: the REM group or DEX group.

RESULTS

A total of 90 patients were enrolled in this study (52 in the REM group and 38 in the DEX group). The mitigation rate, defined as the percentage of patients who were relieved from the initial moderate to severe intolerant status, was greater in the REM group than DEX group at 15 min and 3 h (15 min: 83% vs. 61%, P=0.029; 3 h: 92% vs. 74%, P=0.016), although the mean mitigation rate (81% vs. 85%, P=0.800) was comparable between the two groups. NIV failure, defined as reintubation or death over the course of study, was comparable between the two groups (19.2% vs. 21.1%, respectively, P=0.831). There were no significant differences between the two groups in other clinical outcomes, including tracheostomy (15.4% vs. 15.8%, P=0.958), in-hospital mortality (11.5% vs. 10.5%, P=0.880), ICU length of stay (LOS) (7 vs. 7 days, P=0.802), and in-hospital LOS (17 vs. 19 days, P=0.589).

CONCLUSIONS

REM was as effective as DEX in CS patients with moderate to severe NIV intolerance. Although the effect of REM was better than that of DEX over the first 3 h, the cumulative effect was similar between the two treatments.

Noninvasive Positive Pressure Ventilation for Acute Decompensated Heart Failure

Noninvasive positive pressure ventilation (NIPPV), which can be applied without endotracheal airway or tracheostomy, has been used as the first-line device for patients with acute decompensated heart failure (ADHF) and cardiogenic pulmonary edema. Positive airway pressure (PAP) devices include continuous PAP, bilevel PAP, and adaptive servoventilation. NIPPV can provide favorable physiologic benefits, including improving oxygenation, respiratory mechanics, and pulmonary and systemic hemodynamics. It can also reduce the intubation rate and improve clinical symptoms, resulting in good quality of life and mortality.

Cardiogenic pulmonary edema: mechanisms and treatment - an intensivist's view

PURPOSE OF REVIEW

This review summarizes current understanding of the pathophysiology of cardiogenic pulmonary edema, its causes and treatment.

RECENT FINDINGS

The pathobiology and classification of pulmonary edema is more complex than the hydrostatic vs. permeability dichotomy of the past. Mechanisms of alveolar fluid clearance and factors that affect the clearance rate are under intensive study to find therapeutic strategies. Patients need early stabilization of oxygenation and ventilation, preferably with high-flow nasal cannula oxygen or noninvasive ventilation whereas the diagnostic cause is quickly sought with echocardiography and other testing.

SUMMARY

Treatments must be initiated early, whereas evaluation still is occurring and requires multimodality intervention. The general treatment of cardiogenic pulmonary edema includes diuretics, possibly morphine and often nitrates. The appropriate use of newer approaches - such as, nesiritide, high-dose vasodilators, milrinone, and vasopressin receptor antagonists - needs larger clinical trials.

Dexmedetomidine Improves Cardiovascular and Ventilatory Outcomes in Critically Ill Patients: Basic and Clinical Approaches

Dexmedetomidine (DEX) is a highly selective α2-adrenergic agonist with sedative and analgesic properties, with minimal respiratory effects. It is used as a sedative in the intensive care unit and the operating room. The opioid-sparing effect and the absence of respiratory effects make dexmedetomidine an attractive adjuvant drug for anesthesia in obese patients who are at an increased risk for postoperative respiratory complications. The pharmacodynamic effects on the cardiovascular system are known; however the mechanisms that induce cardioprotection are still under study. Regarding the pharmacokinetics properties, this drug is extensively metabolized in the liver by the uridine diphosphate glucuronosyltransferases. It has a relatively high hepatic extraction ratio, and therefore, its metabolism is dependent on liver blood flow. This review shows, from a basic clinical approach, the evidence supporting the use of dexmedetomidine in different settings, from its use in animal models of ischemia-reperfusion, and cardioprotective signaling pathways. In addition, pharmacokinetics and pharmacodynamics studies in obese subjects and the management of patients subjected to mechanical ventilation are described. Moreover, the clinical efficacy of delirium incidence in patients with indication of non-invasive ventilation is shown. Finally, the available evidence from DEX is described by a group of Chilean pharmacologists and clinicians who have worked for more than 10 years on DEX.

Obstructive sleep apnea and cardiovascular disease, a story of confounders!

Obstructive sleep apnea (OSA) syndrome is increasingly common among middle aged and older adults and is frequently linked to most cardiovascular diseases (CVD). Sleep-disordered breathing and CVD share a number of common risk factors and comorbid conditions including obesity, male gender, advancing age, metabolic syndrome, and hypertension. OSA appears to be associated with worsened CVD outcomes, sleep-related symptoms, quality of life, and risk of motor vehicle accidents. Demonstrating a cause-and-effect relationship between CVD and OSA has been challenging due to shared comorbidities. Strong evidence demonstrating clinically significant benefit for OSA treatments on OSA-related CVD outcomes are limited. In this review, we evaluate potential pathophysiologic mechanisms that link OSA to CVD and focus on specific treatments for OSA, including positive airway pressure (PAP), dental devices, and surgeries with regard to OSA-related CVD outcomes.

Non-Invasive Ventilatory Support In the Elderly

PURPOSE OF REVIEW

The first description of non-invasive ventilation use began in the 1920s. Since then, its role in patient care has evolved through increased clinical knowledge and scientific advancements. The utilization of non-invasive ventilation has broadened from initial application in acute in-hospital ICU settings to now include the outpatient settings. This review discusses the history of non-invasive ventilation and its role in acute in-hospital chronic obstructive pulmonary disease (COPD) exacerbations, cardiogenic pulmonary edema, and weaning from mechanical ventilation in the elderly. The elderly population represents a significant portion of patients hospitalized for the aforementioned conditions. These groups often have more limitations related to the use of invasive mechanical ventilation (IMV), therefore, it is essential to understand the impact of non-invasive ventilation on hospital outcomes.

RECENT FINDINGS

There is strong clinical evidence supporting the use of non-invasive ventilation in patients with respiratory failure secondary to acute COPD exacerbations and cardiogenic pulmonary edema. When compared to standard medical management of these conditions, there is a consistent and significant reduction in the rate of endotracheal intubation and in-hospital mortality.

SUMMARY

The basis of noninvasive ventilation applicability has been determined by significant reduction in mortality and intubation rates. Although survival benefits have been observed, there still remain limitations to the clinical applicability of non-invasive ventilation in certain patient populations and conditions that require further investigation.