Non-invasive ventilation in acute cardiogenic pulmonary oedema

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.

Factors and Outcomes Associated with Failed Noninvasive Positive Pressure Ventilation in Patients with Acute Respiratory Failure

Background

The decision guild for non-invasive positive pressure ventilation (NPPV) application in acute respiratory failure (ARF) patients still needs to work out.

Methods

Adult patients with acute hypoxemic or hypercapnic respiratory failure were recruited and treated with NPPV or primary invasive mechanical ventilation (IMV). Patients’ characteristic and clinical outcomes were recorded. Logistic regression models were used to estimate the adjusted odds ratio (aOR) and 95% confidence intervals for baseline characteristics and clinical outcomes. Subgroup analyses by reason behind successful NPPV were conducted to ascertain if any difference could influence the outcome.

Results

A total of 4525 ARF patients were recruited in our facility between year 2015 and 2017. After exclusion, 844 IMV patients, 66 patients with failed NPPV, and 74 patients with successful NPPV were enrolled. Statistical analysis showed APACHE II score (aOR = 0.93), time between admission and start NPPV (aOR = 0.92), and P/F ratio (aOR = 1.04) were associated with successful NPPV. When comparing with IMV patients, failed NPPV patients displayed a significantly lower APACHE II score, higher Glasgow Coma Scale, longer length of stay in hospital, longer duration of invasive ventilation, RCW/Home ventilator, and some comorbidities.

Conclusion

APACHE II score, time between admission and start NPPV, and PaO2 can be predictors for successful NPPV. The decision of NPPV application is critical as ARF patients with failed NPPV have various worse outcomes than patients receiving primary IMV.

Bilevel positive airway pressure ventilation for non-COPD acute hypercapnic respiratory failure patients: A systematic review and meta-analysis

The effectiveness of bi-level positive airway pressure (BiPAP) in patients with acute hypercapnic respiratory failure (AHRF) due to etiologies other than chronic obstructive pulmonary disease (COPD) is unclear. To systematically review the evidence regarding the effectiveness of BiPAP in non-COPD patients with AHRF. The Cochrane Library, MEDLINE, EMBASE, and CINAHL Plus were searched according to prespecified criteria (PROSPERO-CRD42018089875). Randomized controlled trials (RCTs) assessing the effectiveness of BiPAP versus continuous positive airway pressure (CPAP), invasive mechanical ventilation, or O₂ therapy in adults with non-COPD AHRF were included. The primary outcomes of interest were the rate of endotracheal intubation (ETI) and mortality. Risk-of-bias assessment was performed, and data were synthesized and meta-analyzed where appropriate. Two thousand four hundred and eighty-five records were identified after removing duplicates. Eighty-eight articles were identified for full-text assessment, of which 82 articles were excluded. Six studies, of generally low or uncertain risk-of-bias, were included involving 320 participants with acute cardiogenic pulmonary edema (ACPO) and solid tumors. No significant differences were seen between BiPAP ventilation and CPAP with regard to the rate of progression to ETI (risk ratio [RR] = 1.49, 95% confidence interval [CI], 0.63-3.62, P = 0.37) and in-hospital mortality rate (RR = 0.71, 95% CI, 0.25-1.99, P = 0.51) in patients with AHRF due to ACPO. The efficacy of BiPAP appears similar to CPAP in reducing the rates of ETI and mortality in patients with AHRF due to ACPO. Further research on other non-COPD conditions which commonly cause AHRF such as obesity hypoventilation syndrome is needed.

High-Dose Nitroglycerin Bolus for Sympathetic Crashing Acute Pulmonary Edema: A Prospective Observational Pilot Study

BACKGROUND

Sympathetic crashing acute pulmonary edema (SCAPE) is a severe form of hypertensive acute heart failure with a dramatic presentation. Rapid identification and management in the emergency department (ED) is key to saving these patients and preventing morbidity associated with endotracheal intubation and intensive care treatment. Use of high-dose nitroglycerin (NTG) and noninvasive ventilation (NIV) has been advocated in management of such patients.

OBJECTIVE

To study the feasibility and safety of high-dose NTG combined with NIV in SCAPE.

METHODS

This was a prospective observational pilot study done in the ED of a tertiary care hospital. All patients were treated with high-dose NTG and NIV. The primary objective was to study the feasibility and safety of the SCAPE management protocol in terms of the outcome of the patient. Resolution of symptoms in 6 h and need for intubation were recorded as endpoints. Any complications associated with high-dose NTG were also recorded.

RESULTS

A total of 25 patients were recruited. The mean bolus dose of NTG given was 872 μg, and mean cumulative dose, 35 mg. There was no incidence of hypotension after the bolus dose of nitroglycerin. Eleven patients had resolution of symptoms at 3 h of therapy. Twenty-four patients were discharged from the ED itself after a brief period of observation, and one patient was intubated and shifted to the intensive care unit.

CONCLUSION

Use of our specific SCAPE treatment algorithm, which included high-dose NTG and NIV, was safe and provided rapid resolution of symptoms.

Post partum dyspnoea: look beyond the lungs

The aetiology of acute-onset dyspnoea in the post partum period is diverse. However, subtle clinical and radiological findings assist in early diagnosis and definitive management, thereby conferring better prognosis and survival. https://bit.ly/361b4qm.

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.

Management of hypoxaemia in the critically ill patient

Hypoxaemia is a common presentation in critically ill patients, with the potential for severe harm if not addressed appropriately. This review provides a framework to guide the management of any hypoxaemic patient, regardless of the clinical setting. Key steps in managing such patients include ascertaining the severity of hypoxaemia, the underlying diagnosis and implementing the most appropriate treatment. Oxygen therapy can be delivered by variable or fixed rate devices, and non-invasive ventilation; if patients deteriorate they may require tracheal intubation and mechanical ventilation. Early critical care team involvement is a key part of this pathway. Specialist treatments for severe hypoxaemia can only be undertaken on an intensive care unit and this field is developing rapidly as trial results become available. It is important that each new scenario is approached in a structured manner with an open diagnostic mind and a clear escalation plan.

ISCCM Guidelines for the Use of Non-invasive Ventilation in Acute Respiratory Failure in Adult ICUs

A. ACUTE HYPERCAPNIC RESPIRATORY FAILURE A1. Acute Exacerbation of COPD: Recommendations: NIV should be used in management of acute exacerbation of COPD in patients with acute or acute-on-chronic respiratory acidosis (pH = 7.25-7.35). (1A) NIV should be attempted in patients with acute exacerbation of COPD (pH <7.25 & PaCO2 ≥ 45) before initiating invasive mechanical ventilation (IMV) except in patients requiring immediate intubation. (2A). Lower the pH higher the chance of failure of NIV. (2B) NIV should not to be used routinely in normo- or mildly hyper-capneic patients with acute exacerbation of COPD, without acidosis (pH > 7.35). (2B) A2. NIV in ARF due to Chest wall deformities/Neuromuscular diseases: Recommendations: NIV may be used in patients of ARF due to chest wall deformity/Neuromuscular diseases. (PaCO2 ≥ 45) (UPP) A3. NIV in ARF due to Obesity hypoventilation syndrome (OHS): Recommendations: NIV may be used in AHRF in OHS patients when they present with acute hypercapnic or acute on chronic respiratory failure (pH 45). (3B) NIV/CPAP may be used in obese, hypercapnic patients with OHS and/or right heart failure in the absence of acidosis. (UPP) B. NIV IN ACUTE HYPOXEMIC RESPIRATORY FAILURE: B1. NIV in Acute Cardiogenic Pulmonary Oedema: Recommendations: NIV is recommended in hospital patients with ARF, due to Cardiogenic pulmonary edema. (1A). NIV should be used in patients with acute heart failure/ cardiogenic pulmonary edema, right from emergency department itself. (1B) Both CPAP and BiPAP modes are safe and effective in patients with cardiogenic pulmonary edema. (1A). However, BPAP (NIV-PS) should be preferred in cardiogenic pulmonary edema with hypercapnia. (3A) B2. NIV in acute hypoxemic respiratory failure: Recommendations: NIV may be used over conventional oxygen therapy in mild early acute hypoxemic respiratory failure (P/F ratio <300 and >200 mmHg), under close supervision. (2B) We strongly recommend against a trial of NIV in patients with acute hypoxemic failure with P/F ratio <150. (2A) B3. NIV in ARF due to Chest Trauma: Recommendations: NIV may be used in traumatic flail chest along with adequate pain relief. (3B) B4. NIV in Immunocompromised Host: Recommendations: In Immunocompromised patients with early ARF, we may consider NIV over conventional oxygen. (2B). B5. NIV in Palliative Care: Recommendations: We strongly recommend use of NIV for reducing dyspnea in palliative care setting. (2A) B6. NIV in post-operative cases: Recommendations: NIV should be used in patients with post-operative acute respiratory failure. (2A) B6a. NIV in abdominal surgery: Recommendations: NIV may be used in patients with ARF following abdominal surgeries. (2A) B6b. NIV in bariatric surgery: Recommendations: NIV may be used in post-bariatric surgery patients with pre-existent OSA or OHS. (3A) B6c. NIV in Thoracic surgery: Recommendations: In cardiothoracic surgeries, use of NIV is recommended post operatively for acute respiratory failure to improve oxygenation and reduce chance of reintubation. (2A) NIV should not be used in patients undergoing esophageal surgery. (UPP) B6d. NIV in post lung transplant: Recommendations: NIV may be used for shortening weaning time and to avoid re-intubation following lung transplantation. (2B) B7. NIV during Procedures (ETI/Bronchoscopy/TEE/Endoscopy): Recommendations: NIV may be used for pre-oxygenation before intubation. (2B) NIV with appropriate interface may be used in patients of ARF during Bronchoscopy/Endoscopy to improve oxygenation. (3B) B8. NIV in Viral Pneumonitis ARDS: Recommendations: NIV cannot be considered as a treatment of choice for patients with acute respiratory failure with H1N1 pneumonia. However, it may be reasonable to use NIV in selected patients with single organ involvement, in a strictly controlled environment with close monitoring. (2B) B9. NIV and Acute exacerbation of Pulmonary Tuberculosis: Recommendations: Careful use of NIV in patients with acute Tuberculosis may be considered, with effective infection control precautions to prevent air-borne transmission. (3B) B10. NIV after planned extubation in high risk patients: Recommendation: We recommend that NIV may be used to wean high risk patients from invasive mechanical ventilation as it reduces re-intubation rate. (2B) B11. NIV for respiratory distress post extubation: Recommendations: We recommend that NIV therapy should not be used to manage respiratory distress post-extubation in high risk patients. (2B) C. APPLICATION OF NIV: Recommendation: Choice of mode should be mainly decided by factors like disease etiology and severity, the breathing effort by the patient and the operator familiarity and experience. (UPP) We suggest using flow trigger over pressure triggering in assisted modes, as it provides better patient ventilator synchrony. Especially in COPD patients, flow triggering has been found to benefit auto PEEP. (3B) D. MANAGEMENT OF PATIENT ON NIV: D1. Sedation: Recommendations: A non-pharmacological approach to calm the patient (Reassuring the patient, proper environment) should always be tried before administrating sedatives. (UPP) In patients on NIV, sedation may be used with extremely close monitoring and only in an ICU setting with lookout for signs of NIV failure. (UPP) E. EQUIPMENT: Recommendations: We recommend that portable bilevel ventilators or specifically designed ICU ventilators with non-invasive mode should be used for delivering Non–invasive ventilation in critically ill patients. (UPP) Both critical care ventilators with leak compensation and bi-level ventilators have been equally effective in decreasing the WOB, RR, and PaCO2. (3B) Currently, Oronasal mask is the most preferred interface for non-invasive ventilation for acute respiratory failure. (3B) F. WEANING: Recommendations: We recommend that weaning from NIV may be done by a standardized protocol driven approach of the unit. (2B)

How to cite this article: Chawla R, Dixit SB, Zirpe KG, Chaudhry D, Khilnani GC, Mehta Y, et al. ISCCM Guidelines for the Use of Non-invasive Ventilation in Acute Respiratory Failure in Adult ICUs. Indian J Crit Care Med 2020;24(Suppl 1):S61–S81.

Positive Pressure Ventilation in Cardiogenic Shock: Review of the Evidence and Practical Advice for Patients With Mechanical Circulatory Support

Cardiogenic shock (CS) is often complicated by respiratory failure, and more than 80% of patients with CS require respiratory support. Elevated filling pressures from left-ventricular (LV) dysfunction lead to alveolar pulmonary edema, which impairs both oxygenation and ventilation. The implementation of positive pressure ventilation (PPV) improves gas exchange and can improve cardiovascular hemodynamics by reducing preload and afterload of the LV, reducing mitral regurgitation and decreasing myocardial oxygen demand, all of which can help augment cardiac output and improve tissue perfusion. In right ventricular (RV) failure, however, PPV can potentially decrease preload and increase afterload, which can potentially lead to hemodynamic deterioration. Thus, a working understanding of cardiopulmonary interactions during PPV in LV and RV dominant CS states is required to safely treat this complex and high-acuity group of patients with respiratory failure. Herein, we provide a review of the published literature with a comprehensive discussion of the available evidence on the use of PPV in CS. Furthermore, we provide a practical framework for the selection of ventilator settings in patients with and without mechanical circulatory support, induction, and sedation methods, and an algorithm for liberation from PPV in patients with CS.

Comparison of high-flow nasal cannula oxygen therapy and non-invasive ventilation as first-line therapy in respiratory failure: a multicenter retrospective study

Aim

To identify which subgroups of respiratory failure could benefit more from high‐flow nasal cannula oxygen therapy (HFNC) or non‐invasive ventilation (NIV).

Methods

We undertook a multicenter retrospective study of patients with acute respiratory failure (ARF) who received HFNC or NIV as first‐line respiratory support between January 2012 and December 2017. The adjusted odds ratios (OR) with 95% confidence intervals (CI) for HFNC versus NIV were calculated for treatment failure and 30‐day mortality in the overall cohort and in patient subgroups.

Results

High‐flow nasal cannula oxygen therapy and NIV were used in 200 and 378 patients, and the treatment failure and 30‐day mortality rates were 56% and 34% in the HFNC group and 41% and 39% in the NIV group, respectively. The risks of treatment failure and 30‐day mortality were not significantly different between the two groups. In subgroup analyses, HFNC was associated with increased risk of treatment failure in patients with cardiogenic pulmonary edema (adjusted OR 6.26; 95% CI, 2.19–17.87; P < 0.01) and hypercapnia (adjusted OR 3.70; 95% CI, 1.34–10.25; P = 0.01), but the 30‐day mortality was not significantly different in these subgroups. High‐flow nasal cannula oxygen therapy was associated with lower risk of 30‐day mortality in patients with pneumonia (adjusted OR 0.43; 95% CI, 0.19–0.94; P = 0.03) and in patients without hypercapnia (adjusted OR 0.51; 95% CI, 0.30–0.88; P = 0.02).

Conclusion

High‐flow nasal cannula oxygen therapy could be more beneficial than NIV in patients with pneumonia or non‐hypercapnia, but not in patients with cardiogenic pulmonary edema or hypercapnia.

Noninvasive ventilation in acute hypoxic respiratory failure in medical intensive care unit: A study in rural medical college

Introduction:

Noninvasive ventilation (NIV) has emerged as an important tool for the management of acute hypoxic respiratory failure (AHRF) and has been the area of research in the last two decades. In this study, we have tried to find out the outcome of NIV in patients with AHRF.

Materials and Methods:

In this prospective, observational study, all the patients of AHRF requiring NIV were enrolled, and heart rate (HR), respiratory rate (RR), arterial blood gas parameters, and NIV settings at baseline, 1 h, and 4 h were collected. The patients were classified as AHRF with acute respiratory distress syndrome (ARDS) and AHRF without ARDS, which were further classified according to the outcome.

Results:

Among 200 patients admitted in medical intensive care unit (ICU), 50 patients (27 with ARDS and 23 without ARDS) were put on NIV. There was a significant improvement in HR, RR, PaO ₂, and inspiratory positive airway pressure after 1 and 4 h and significant improvement at 4 h in expiratory positive airway pressure in all the groups on NIV. Length of ICU stay and hospital stay was less in the nonintubated group. Mortality rate was 25.92% in the intubated group, while it was nil in the nonintubated group.

Conclusion:

NIV found to reduce the endotracheal intubation and mortality, by improving the outcome of the patient.

Pressure support ventilation vs Continuous positive airway pressure for treating of acute cardiogenic pulmonary edema: A pilot study

Non-invasive ventilation is usually adopted as a support to medical therapy in patients with acute pulmonary edema, but which modality between Pressure Support Ventilation (PSV) and Continuous Positive Airway Pressure (CPAP) has better favourable effects is not been yet well known. Aim of this observational study was to provide data on these different non-invasive ventilation modalities in the management of acute cardiogenic pulmonary edema. One-hundred-fifty-three patients consecutively admitted to the Emergency Room of two different Center were enrolled and randomly assigned to CPAP or PSV. Data relative to mortality, need of endotracheal intubation, sequential blood gas analysis were compared. Furthermore, there were no significant differences regarding mortality in the two groups, but patients treated with PSV had a significant lower rate of endotracheal intubation and a higher improvement of blood gas analyses parameters. In conclusion, our data support only a slight advantage in favour to PSV versus CPAP.

Brazilian recommendations of mechanical ventilation 2013. Part 2

Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document.

Sympathetic crashing acute pulmonary edema

Sympathetic crashing acute pulmonary edema (SCAPE) is the extreme end of the spectrum of acute pulmonary edema. It is important to understand this disease as it is relatively common in the emergency department (ED) and has better outcomes when managed appropriately. The patients have an abrupt redistribution of fluid in the lungs, and when treated promptly and effectively, these patients will rapidly recover. Noninvasive ventilation and intravenous nitrates are the mainstay of treatment which should be started within minutes of the patient's arrival to the ED. Use of morphine and intravenous loop diuretics, although popular, has poor scientific evidence.

A study on the role of noninvasive ventilation in mild-to-moderate acute respiratory distress syndrome

Aim:

There is sparse data on the role of noninvasive ventilation (NIV) in acute respiratory distress syndrome (ARDS) from India. Herein, we report our experience with the use of NIV in mild to moderate ARDS.

Materials and Methods:

This was a prospective observational study involving consecutive subjects of ARDS treated with NIV using an oronasal mask. Patients were monitored clinically with serial arterial blood gas analysis. The success of NIV, duration of NIV use, Intensive Care Unit stay, hospital mortality, and improvement in clinical and blood gas parameters were assessed. The success of NIV was defined as prevention of endotracheal intubation.

Results:

A total of 41 subjects (27 women, mean age: 30.9 years) were included in the study. Tropical infections followed by abdominal sepsis were the most common causes of ARDS. The use of NIV was successful in 18 (44%) subjects, while 23 subjects required intubation. The median time to intubation was 3 h. Overall, 19 (46.3%) deaths were encountered, all in those requiring invasive ventilation. The mean duration of ventilation was significantly higher in the intubated patients (7.1 vs. 2.6 days, P = 0.004). Univariate analysis revealed a lack of improvement in PaO₂/FiO₂ at 1 h and high baseline Acute Physiology and Chronic Health Evaluation II (APACHE II) as predictors of NIV failure.

Conclusions:

Use of NIV in mild to moderate ARDS helped in avoiding intubation in about 44% of the subjects. A baseline APACHE II score of >17 and a PaO₂/FiO₂ ratio <150 at 1 h predicts NIV failure.

Acute hemodynamic effects of adaptive servoventilation in patients with pre-capillary and post-capillary pulmonary hypertension

RATIONALE

The hemodynamic effects of adaptive servoventilation (ASV) in patients with pulmonary hypertension (PH) are unknown.

METHODS

A series of clinically stable patients with pre- or post-capillary PH underwent ASV therapy (endexpiratory positive airway pressure support 12-14 cm H2O, pressure support 4-10 cm H2O) during right heart catheterization. Hemodynamics were measured at rest, at the end of a 15-min episode of ASV therapy, and 15 min after ASV completion. Hemodynamic variables included heart rate, blood pressure, right atrial pressure (RAP), mean pulmonary artery pressure (PAPm), pulmonary arterial wedge pressure (PAWP), cardiac output and pulmonary vascular resistance (PVR).

RESULTS

The study enrolled 33 patients; 12 patients with post-capillary PH due to heart failure with preserved ejection fraction, and 21 patients with pre-capillary PH due to pulmonary arterial hypertension (n = 8) or chronic thromboembolic pulmonary hypertension (n = 13). ASV was well tolerated by all patients and resulted in reductions in systolic blood pressure (-8 mmHg, p = 0.01), PAPm (-5 mmHg, p <0.001) and PVR (-10%, p = 0.01). Right and left filling pressure increased, while the cardiac output decreased (-0.4 L/min; p < 0.001). The hemodynamic effects of ASV were similar in both patient populations.

CONCLUSIONS

ASV had moderate hemodynamic effects in patients with PH of various origins, most importantly a decline in systolic blood pressure, PAPm and cardiac output. ASV was safe and well tolerated during this short-term study, but the observed drop in blood pressure and cardiac output may be of concern if ASV is applied in patients with advanced PH and severely impaired right ventricular function.

Brazilian recommendations of mechanical ventilation 2013. Part 2

Perspectives on invasive and noninvasive ventilatory support for critically ill patients are evolving, as much evidence indicates that ventilation may have positive effects on patient survival and the quality of the care provided in intensive care units in Brazil. For those reasons, the Brazilian Association of Intensive Care Medicine (Associação de Medicina Intensiva Brasileira - AMIB) and the Brazilian Thoracic Society (Sociedade Brasileira de Pneumologia e Tisiologia - SBPT), represented by the Mechanical Ventilation Committee and the Commission of Intensive Therapy, respectively, decided to review the literature and draft recommendations for mechanical ventilation with the goal of creating a document for bedside guidance as to the best practices on mechanical ventilation available to their members. The document was based on the available evidence regarding 29 subtopics selected as the most relevant for the subject of interest. The project was developed in several stages, during which the selected topics were distributed among experts recommended by both societies with recent publications on the subject of interest and/or significant teaching and research activity in the field of mechanical ventilation in Brazil. The experts were divided into pairs that were charged with performing a thorough review of the international literature on each topic. All the experts met at the Forum on Mechanical Ventilation, which was held at the headquarters of AMIB in São Paulo on August 3 and 4, 2013, to collaboratively draft the final text corresponding to each sub-topic, which was presented to, appraised, discussed and approved in a plenary session that included all 58 participants and aimed to create the final document.

[Prehospital non-invasive ventilation in Germany: results of a nationwide survey of ground-based emergency medical services]

BACKGROUND AND OBJECTIVES

Non-invasive ventilation (NIV) is an evidence-based treatment of acute respiratory failure and can be helpful to reduce morbidity and mortality. In Germany national S3 guidelines for inhospital use of NIV based on a large number of clinical trials were published in 2008; however, only limited data for prehospital non-invasive ventilation (pNIV) and hence no recommendations for prehospital use exist so far.

AIM

In order to create a database for pNIV in Germany a nationwide survey was conducted to explore the status quo for the years 2005-2008 and to survey expected future developments including disposability, acceptance and frequency of pNIV.

MATERIAL AND METHODS

A questionnaire on the use of pNIV was developed and distributed to 270 heads of medical emergency services in Germany.

RESULTS

Of the 270 questionnaires distributed 142 could be evaluated (52 %). The pNIV was rated as a reasonable treatment option in 91 % of the respondents but was available in only 54 out of the 142 responding emergency medical services (38 %). Continuous positive airway pressure (98 %) and biphasic positive airway pressure (22 %) were the predominantly used ventilation modes. Indications for pNIV use were acute cardiogenic pulmonary edema (96 %), acute exacerbation of chronic obstructive pulmonary disease (89 %), asthma (32 %) and pneumonia (28 %). Adverse events were reported for panic (20 ±  17%) and non-threatening heart rhythm disorders (8 ± 5%), the rate of secondary intubation was low (reduction from 20 % to 10 %) and comparable to data from inhospital treatment.

CONCLUSION

Prehospital NIV in Germany was used by only one third of all respondents by the end of 2008. Based on the clinical data a growing application for pNIV is expected. Controlled prehospital studies are needed to enunciate evidence-based recommendations for pNIV.

Noninvasive mechanical ventilation: An 18-month experience of two tertiary care hospitals in north India

BACKGROUND

Noninvasive mechanical ventilation (NIMV) is the delivery of positive pressure ventilation through an interface to upper airways without using the invasive airway. Use of NIMV is becoming common with the increasing recognition of its benefits.

OBJECTIVES

This study was done to evaluate the feasibility and outcome of NIMV in tertiary care centres.

MATERIALS AND METHODS

An observational, retrospective study conducted over a period of 18 months in two tertiary level hospitals of north India on 184 consecutive patients who were treated by NIMV, regardless of the indication. NIMV was given in accordance with the arterial blood gas (ABG) parameters defining respiratory failure (Type 1/Type 2).

RESULTS

The most common indication of NIMV in our hospitals was acute exacerbation of chronic obstructive pulmonary disease (AE-COPD 80.43%), and 90.54% AE-COPD patients were improved by NIMV. Application of NIMV resulted in significant improvement of pH and blood gases in COPD patients, while non-COPD patients showed significant improvement in partial pressure of oxygen (PaO2) alone. The mean duration of NIMV was 8.35 ± 5.98 days, and patients of interstitial lung disease (ILD) were on NIMV for the maximum duration (17 ± 8.48 days). None of the patients of acute respiratory distress syndrome were cured by NIMV; 13.04% patients on NIMV required intubation and mechanical ventilation.

CONCLUSION

This study demonstrates and encourages the use of NIMV as the first-line ventilatory treatment in AE-COPD patients with respiratory failure. It also supports NIMV usage in other causes of respiratory failure as a promising step toward prevention of mechanical ventilation.

Noninvasive ventilation in chest trauma: systematic review and meta-analysis

PURPOSE

Single studies of Noninvasive Ventilation (NIV) in the management of acute respiratory failure in chest trauma patients have produced controversial findings. The aim of this study is to critically review the literature to investigate whether NIV reduces mortality, intubation rate, length of stay and complications in patients with chest trauma, compared to standard therapy.

METHODS

We performed a systematic review and meta-analysis of randomized controlled trials, prospective and retrospective observational studies, by searching PubMed, EMBASE and bibliographies of articles retrieved. We screened for relevance studies that enrolled adults with chest trauma who developed mild to severe acute respiratory failure and were treated with NIV. We included studies reporting at least one clinical outcome of interest to perform a meta-analysis.

RESULTS

Ten studies (368 patients) met the inclusion criteria and were included for the meta-analysis. Five studies (219 patients) reported mortality and results were quite homogeneous across studies, with a summary relative risk for patients treated with NIV compared with standard care (oxygen therapy and invasive mechanical ventilation) of 0.26 (95 % confidence interval 0.09-0.71, p = 0.003). There was no advantage in mortality of continuous positive airway pressure over noninvasive pressure support ventilation. NIV significantly increased arterial oxygenation and was associated with a significant reduction in intubation rate, in the incidence of overall complications and infections.

CONCLUSIONS

These results suggest that NIV could be useful in the management of acute respiratory failure due to chest trauma.

Successful treatment of gefitinib-induced acute interstitial pneumonitis with corticosteroid and non-invasive BIPAP-ventilation

This is the case of a 63 year-old male who was diagnosed adenocarcinoma in the left upper lung with ipsilateral malignant pleural effusion. At diagnosis it had already spread to left pulmonary HLN (hilar lymph node) and left supraclavicular lymph node and mediastinal lymph nodes. The patient received combined chemotherapy with bevacizumab and GP (gemcitabine and carboplatin) for 6 courses. Disease progression on chest CT scan was recognized, daily treatment with oral gefitinib (250 mg/day) was commenced. One week later, he was admitted under the impression of gefitinib-related interstitial pneumonitis, gefitinib was discontinued immediately and methylprednisolone with BIPAP assisted ventilation were used. The patient was followed up for 2 months after the start of treatment with corticosteroids and BIPAP assisted ventilation and remained well.

Dexmedetomidine versus midazolam for the sedation of patients with non-invasive ventilation failure

OBJECTIVE

To compare the efficacy and safety of sedation with dexmedetomidine vs. midazolam for patients with acute cardiogenic pulmonary edema and hypoxemia during the treatment of non-invasive ventilation (NIV).

METHODS

The intensive care unit (ICU) patients treated in our hospital between March 2008 and August 2011 who had acute pulmonary edema and hyoxemia in NIV failure due to patient refusal to continue the NIV sessions (due to discomfort) were enrolled in this study. The patients were divided into two groups by the random numerical table method. They were treated with either midazolam (29 cases) or dexmedetomidine (33 cases). The patients were sedated (Ramsay scale 2-3) by a continuous perfusion of midazolam or dexmedetomidine during the NIV session. Cardiorespiratory and ventilatory parameters, the results of the blood gas analysis, and adverse events were prospectively recorded. The main outcome measure was the percentage of endotracheal intubation during NIV. Secondary endpoints included the duration of non-invasive mechanical ventilation, length of ICU stay, and adverse events.

RESULTS

In both groups of patients, the expected sedative scores were obtained. The cardiorespiratory symptoms and signs (oxygenation index, pH value, and respiratory rate) were significantly improved in both groups. In the dexmedetomidine-treated group, the patients had a further decreased percentage of failure of NIV requiring endotracheal intubation (ETI) and a more prolonged mean time to ETI (p=0.042, p=0.024). Furthermore, when compared with the group treated with midazolam, the overall duration of mechanical ventilation and the duration of ICU hospitalization in the group treated with dexmedetomidine were markedly decreased, and weaning from mechanical ventilation was easier (p=0.010, p=0.042). Despite the fact that more dexmedetomidine-treated patients developed bradycardia (18.2% vs. 0, p=0.016), no patients required an intervention or interruption of study drug infusion. Conversely, the incidence of respiratory infections and vomiting was lower in the dexmedetomidine-treated patients (p=0.026, p=0.010).

CONCLUSION

Dexmedetomidine led to a more desired level of awaking sedation, shortened the duration of mechanical ventilation and the length of the ICU stay, and further reduced the prevalence of nosocomial infection for NIV sedation in patients with acute cardiogenic pulmonary edema. It appears to provide several advantages and safe control compared with the γ-amino butyric acid (GABA) agonist midazolam.

Predicting the success of noninvasive positive pressure ventilation in emergency room for patients with acute heart failure

BACKGROUND

Non-invasive positive pressure ventilation (NPPV) for acute heart failure (AHF) is increasingly used to avoid endotracheal intubation (ETI). We therefore reviewed our experience using respirator management in the emergency room for AHF, and evaluated the predictive factors in the success of NPPV in the emergency room.

METHODS AND RESULTS

Three-hundred forty-three patients with AHF were analyzed. The AHF patients were assigned to either BiPAP-Synchrony (B-S; Respironics, Merrysville, PA, USA) period (2005-2007, n = 176) or BiPAP-Vision (B-V; Respironics) period (2008-2010, n = 167). The rate of carperitide use was significantly increased and dopamine use was significantly decreased in the B-V period. The total length of hospital stay was significantly shorter in the B-V period. AHF patients were also assigned to a failed trial of NPPV followed by ETI (NPPV failure group) or an NPPV success group in the emergency room for each period. NPPV was successfully used in 48 cases in the B-S period, and in 111 cases in the B-V period. Fifty-seven ETI patients included 45 direct ETI and 11 NPPV failure cases in the B-S period, and 16 ETI patients included 10 direct ETI and 6 NPPV failure cases in the B-V period. The pH values were significantly lower in the NPPV failure than in the NPPV success for both periods (7.19 ± 0.10 vs. 7.28 ± 0.11, B-S period, p < 0.05; 7.05 ± 0.08 vs. 7.27 ± 0.14, B-V period, p < 0.001). A pH value of 7.20 produced the optimal balance in the B-S period, while that of 7.03 produced the optimal balance in B-V periods by the ROC curve analysis. The cutoff value of pH was lower in the B-V period than in the B-S period.

CONCLUSIONS

This predictive value provides successful estimates of NPPV with a high sensitivity and specificity, and the aortic blood gas level was above 7.03 pH when using the B-V system.

The role of continuous positive airway pressure in acute cardiogenic edema with preserved left ventricular systolic function

OBJECTIVE

The objective of the study was to compare the effect of continuous positive airway pressure (CPAP) in patients with acute cardiogenic pulmonary edema (ACPE) with preserved or impaired left ventricular systolic function with regard to resolution time.

METHODS

In a prospective, preliminary observational cohort study, 18 patients with preserved left ventricular systolic function (group A) and 18 patients with systolic heart dysfunction (group B) with ACPE underwent CPAP (10 cmH(2)0) through a face mask with standard medical therapy after a morphologic echocardiographic investigation shortly before CPAP.

RESULTS

Resolution time did not differ significantly between the 2 groups of patients (64 +/- 25 minutes in diastolic group vs 80 +/- 33 minutes in systolic group). One patient in preserved left ventricular systolic function group required endotracheal intubation (not statistically significant). No patient died during hospital stay. Arterial blood gases improved after a trial of CPAP in both groups of patients.

CONCLUSIONS

The results of this preliminary study show that resolution time is not significantly different in patients with ACPE with preserved or impaired systolic function submitted to CPAP.

Continuous positive airway pressure vs. pressure support ventilation in acute cardiogenic pulmonary edema: a randomized trial

BACKGROUND

Both non-invasive continuous positive airway pressure (nCPAP) and non-invasive pressure support ventilation (nPSV) have been shown to be effective treatment for acute cardiogenic pulmonary edema (ACPE). In patients with severe ACPE who are treated with standard medical treatment, the baseline intubation rate is approximately 24%.

STUDY OBJECTIVE

This study was conducted to compare the endotracheal intubation (ETI) rate using two techniques, nCPAP vs. nPSV. In addition, mortality rate, improvement in gas exchange, duration of ventilation, and hospital length of stay were also assessed.

METHODS

This prospective, multi-center, randomized study enrolled 80 patients with ACPE who were randomized to receive nCPAP or nPSV (40 patients in each group) via an oronasal mask. Inclusion criteria were severe dyspnea, respiratory rate > 30 breaths/min, use of respiratory accessory muscles, or PaO(2)/FiO(2) < 200.

RESULTS

ETI was required in 0 (0%) and in 3 (7.5%) patients in the nCPAP group and in the nPSV group, respectively (p = 0.241). No significant difference was observed in in-hospital mortality: 2 (5%) vs. 7 (17.5%) in nCPAP and nPSV groups, respectively (p = 0.154). No difference in hospital length of stay was observed between the two groups, nor was there a difference observed in duration of ventilation, despite a trend for reduced time with nPSV vs. nCPAP (5.91 ± 4.01 vs. 8.46 ± 7.14 h, respectively, p = 0.052). Both nCPAP and nPSV were effective in improving gas exchange, including in the subgroup of hypercapnic patients.

CONCLUSIONS

Both methods are effective treatment for patients with ACPE. Non-invasive CPAP should be considered as the first line of treatment because it is easier to use and less expensive than non-invasive PSV.

Noninvasive ventilation in acute cardiogenic pulmonary edema

BACKGROUND

Noninvasive ventilation (continuous positive airway pressure [CPAP] or noninvasive intermittent positive-pressure ventilation [NIPPV]) appears to be of benefit in the immediate treatment of patients with acute cardiogenic pulmonary edema and may reduce mortality. We conducted a study to determine whether noninvasive ventilation reduces mortality and whether there are important differences in outcome associated with the method of treatment (CPAP or NIPPV).

METHODS

In a multicenter, open, prospective, randomized, controlled trial, patients were assigned to standard oxygen therapy, CPAP (5 to 15 cm of water), or NIPPV (inspiratory pressure, 8 to 20 cm of water; expiratory pressure, 4 to 10 cm of water). The primary end point for the comparison between noninvasive ventilation and standard oxygen therapy was death within 7 days after the initiation of treatment, and the primary end point for the comparison between NIPPV and CPAP was death or intubation within 7 days.

RESULTS

A total of 1069 patients (mean [+/-SD] age, 77.7+/-9.7 years; female sex, 56.9%) were assigned to standard oxygen therapy (367 patients), CPAP (346 patients), or NIPPV (356 patients). There was no significant difference in 7-day mortality between patients receiving standard oxygen therapy (9.8%) and those undergoing noninvasive ventilation (9.5%, P=0.87). There was no significant difference in the combined end point of death or intubation within 7 days between the two groups of patients undergoing noninvasive ventilation (11.7% for CPAP and 11.1% for NIPPV, P=0.81). As compared with standard oxygen therapy, noninvasive ventilation was associated with greater mean improvements at 1 hour after the beginning of treatment in patient-reported dyspnea (treatment difference, 0.7 on a visual-analogue scale ranging from 1 to 10; 95% confidence interval [CI], 0.2 to 1.3; P=0.008), heart rate (treatment difference, 4 beats per minute; 95% CI, 1 to 6; P=0.004), acidosis (treatment difference, pH 0.03; 95% CI, 0.02 to 0.04; P<0.001), and hypercapnia (treatment difference, 0.7 kPa [5.2 mm Hg]; 95% CI, 0.4 to 0.9; P<0.001). There were no treatment-related adverse events.

CONCLUSIONS

In patients with acute cardiogenic pulmonary edema, noninvasive ventilation induces a more rapid improvement in respiratory distress and metabolic disturbance than does standard oxygen therapy but has no effect on short-term mortality. (Current Controlled Trials number, ISRCTN07448447.)

Noninvasive positive pressure ventilation in acute respiratory failure due to COPD vs other causes: effectiveness and predictors of failure in a respiratory ICU in North India

OBJECTIVES

To determine the effectiveness of noninvasive positive pressure ventilation (NIPPV), and the factors predicting failure of NIPPV in acute respiratory failure (ARF) due to chronic obstructive pulmonary disease (COPD) versus other causes of ARF.

PATIENTS AND METHODS

This was a prospective observational study and all patients with ARF requiring NIPPV over a one-and-a-half year period were enrolled in the study. We recorded the etiology of ARF and prospectively collected the data for heart rate, respiratory rate, arterial blood gases (pH, partial pressure of oxygen in the arterial blood [PaO2], partial pressure of carbon dioxide in arterial blood [PaCO2]) at baseline, one and four hours. The patients were further classified into two groups based on the etiology of ARF as COPD-ARF and ARF due to other causes. The primary outcome was the need for endotracheal intubation during the intensive care unit (ICU) stay.

RESULTS

During the study period, 248 patients were admitted in the ICU and of these 63 (25.4%; 24, COPD-ARF, 39, ARF due to other causes; 40 male and 23 female patients; mean [standard deviation] age of 45.7 [16.6] years) patients were initiated on NIPPV. Patients with ARF secondary to COPD were older, had higher APACHE II scores, lower respiratory rates, lower pH and higher PaCO2 levels compared to other causes of ARF. After one hour there was a significant decrease in respiratory rate and heart rate and decline in PaCO2 levels with increase in pH and PaO2 levels in patients successfully managed with NIPPV. However, there was no difference in improvement of clinical and blood gas parameters between the two groups except the rate of decline of pH at one and four hours and PaCO2 at one hour which was significantly faster in the COPD group. NIPPV failures were significantly higher in ARF due to other causes (15/39) than in ARF-COPD (3/24) (p = 0.03). The mean ICU and hospital stay and the hospital mortality were similar in the two groups. In the multivariate logistic regression model (after adjusting for gender, APACHE II scores and improvement in respiratory rate, pH, PaO2 and PaCO2 at one hour) only the etiology of ARF, ie, ARF-COPD, was associated with a decreased risk of NIPPV failure (odds ratio 0.23; 95% confidence interval, 0.58-0.9).

CONCLUSIONS

NIPPV is more effective in preventing endotracheal intubation in ARF due to COPD than other causes, and the etiology of ARF is an important predictor of NIPPV failure.

Noninvasive ventilation in Plasmodium vivax related ALI/ARDS

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), complications of P. falciparum malaria are associated with a very high mortality but are rarely seen in P. vivax malaria. Herein, we report a 28-year old woman who developed ARDS after infection with P. vivax. In a systematic review the literature for the use of noninvasive ventilation (NIV) in cases of ALI/ARDS related to P. vivax, from among 45 reports noninvasive positive pressure ventilation (NIPPV) was used in the management of three cases of ALI/ARDS related to P. vivax. The use of NIV in vivax malaria related ALI/ARDS is associated with a good outcome.

A comparison of continuous and bi-level positive airway pressure non-invasive ventilation in patients with acute cardiogenic pulmonary oedema: a meta-analysis

INTRODUCTION

We conducted the present study to investigate the potential beneficial and adverse effects of continuous positive airway pressure (CPAP) compared with bi-level positive airway pressure (BiPAP) noninvasive ventilation in patients with cardiogenic pulmonary oedema.

METHOD

We included randomized controlled studies comparing CPAP and BiPAP treatment in patients with cardiogenic pulmonary oedema from the Cochrane Controlled Trials Register (2005 issue 3), and EMBASE and MEDLINE databases (1966 to 1 December 2005), without language restriction. Two reviewers reviewed the quality of the studies and independently performed data extraction.

RESULTS

Seven randomized controlled studies, including a total of 290 patients with cardiogenic pulmonary oedema, were considered. The hospital mortality (relative risk [RR] 0.76, 95% confidence interval [CI] 0.32-1.78; P = 0.52; I2 = 0%) and risk for requiring invasive ventilation (RR 0.80, 95% CI 0.33-1.94; P = 0.62; I2 = 0%) were not significantly different between patients treated with CPAP and those treated with BiPAP. Stratifying studies that used either fixed or titrated pressure during BiPAP treatment and studies involving patients with or without hypercapnia did not change the results. The duration of noninvasive ventilation required until the pulmonary oedema resolved (weighted mean difference [WMD] in hours = 3.65, 95% CI -12.12 to +19.43; P = 0.65, I2 = 0%) and length of hospital stay (WMD in days = -0.04, 95% CI -2.57 to +2.48; P = 0.97, I2 = 0%) were also not significantly different between the two groups. Based on the limited data available, there was an insignificant trend toward an increase in new onset acute myocardial infarction in patients treated with BiPAP (RR 2.10, 95% CI 0.91-4.84; P = 0.08; I2 = 25.3%).

CONCLUSION

BiPAP does not offer any significant clinical benefits over CPAP in patients with acute cardiogenic pulmonary oedema. Until a large randomized controlled trial shows significant clinical benefit and cost-effectiveness of BiPAP versus CPAP in patients with acute cardiogenic pulmonary oedema, the choice of modality will depend mainly on the equipment available.

Is there a role for noninvasive ventilation in acute respiratory distress syndrome? A meta-analysis

The role of noninvasive ventilation (NIV) in the management of acute respiratory distress syndrome (ARDS) is controversial. The aim of this study was to assess the effect of NIV on the rate of endotracheal intubation and intensive care unit (ICU) mortality in patients with ARDS. We searched the MEDLINE database for relevant studies published from 1980 to September 2005, and included studies if (a) the design was a randomized controlled trial; (b) patients had ARDS irrespective of the underlying etiology; (c) the interventions compared NIV and medical therapy with medical therapy alone; and (d) outcomes included need for endotracheal intubation and/or ICU survival. The addition of NIV to standard care in the setting of ARDS did not reduce the rate of endotracheal intubation (absolute risk reduction (RR) 13.5%, 95% confidence interval (CI) -5.2% to 31.3%), and had no effect on ICU survival (absolute RR 4.8%, 95% CI -12.8% to 22.1%). However, the trial results were significantly heterogeneous. Thus, current evidence suggests that patients with ARDS are unlikely to have any significant benefits on outcome when NIV is added to standard therapy. However, this analysis is limited by the presence of significant heterogeneity; hence large randomized controlled trials are required to settle this issue.