CPAP, effective respiratory support in patients with AIDS-related Pneumocystis carinii pneumonia

The use of non-invasive ventilation during acute respiratory failure due to pneumonia

The use of non-invasive ventilation in patients with community-acquired pneumonia is controversial since this is associated with high rates of treatment failure, compared with other causes of severe acute respiratory failure. The populations of patients with community-acquired pneumonia who have demonstrated better response to non-invasive ventilation are those with previous cardiac or respiratory disease, particularly chronic obstructive pulmonary disease. By contrast, the use of non-invasive ventilation in patients with community-acquired pneumonia without these pre-existing diseases should be very cautious and under strict monitoring conditions, since there are increasing evidences that the unnecessary delay in intubation of those patients who fail treatment with non-invasive ventilation is associated with lower survival. Pulmonary complications of immunosuppressed patients are associated with high rates of intubation and mortality. The use of non-invasive ventilation in these patients may decrease the need for intubation and improve the poor outcome associated with these complications. Continuous positive airway pressure has been used to treat acute respiratory failure in several conditions characterised by alveolar collapse. While this is extremely useful in patients with acute cardiogenic pulmonary oedema, the efficacy in pneumonia seems limited to immunosuppressed patients with pulmonary complications. Conversely, there are no sufficient evidences on the efficacy of continuous positive airway pressure in immunocompetent patients with pneumonia and severe acute respiratory failure.

Oxygen therapy for pneumonia in adults

BACKGROUND

Oxygen therapy is widely used in the treatment of lung diseases. However, the effectiveness of oxygen therapy as a treatment for pneumonia is not well known.

OBJECTIVES

To determine the effectiveness and safety of oxygen therapy in the treatment of pneumonia in adults older than 18 years.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) 2011, Issue 4, part of The Cochrane Library, www.thecochranelibrary.com (accessed 9 December 2011), which includes the Cochrane Acute Respiratory Infections Group's Specialised Register, MEDLINE (1948 to November week 3, 2011) and EMBASE (1974 to December 2011).

SELECTION CRITERIA

Randomised controlled trials (RCTs) of oxygen therapy for adults with community-acquired pneumonia (CAP) and nosocomial (hospital-acquired) pneumonia (HAP or NP) in intensive care units (ICU).

DATA COLLECTION AND ANALYSIS

Two review authors independently reviewed abstracts and assessed data for methodological quality.

MAIN RESULTS

Three RCTs met our inclusion criteria. The studies enrolled 151 participants with CAP or immunosuppressed patients with pulmonary infiltrates. Overall, we found that non-invasive ventilation can reduce the risk of death in the ICU, odd ratio (OR) 0.28, 95% confidence interval (CI) 0.09 to 0.88; endotracheal intubation, OR 0.26, 95% CI 0.11 to 0.61; complications, OR 0.23, 95% CI 0.08 to 0.70; and shorten ICU length of stay, mean duration (MD) -3.28, 95% CI -5.41 to -1.61.Non-invasive ventilation and standard oxygen supplementation via a Venturi mask were similar when measuring mortality in hospital, OR 0.54, 95% CI 0.11 to 2.68; two-month survival, OR 1.67, 95% CI 0.53 to 5.28; duration of hospital stay, MD -1.00, 95% CI -2.05 to 0.05; and duration of mechanical ventilation, standard MD -0.26, 95% CI -0.66 to 0.14. Some outcomes and complications of non-invasive ventilation were varied according to different participant populations. We also found that some subgroups had a high level of heterogeneity when conducting pooled analyses.

AUTHORS' CONCLUSIONS

Non-invasive ventilation can reduce the risk of death in the ICU, endotracheal intubation, shorten ICU stay and length of intubation. Some outcomes and complications of non-invasive ventilation were varied according to different participant populations. Other than the oxygen therapy, we must mention the importance of standard treatment by physicians. The evidence is weak and we did not include participants with pulmonary tuberculosis and cystic fibrosis. More RCTs are required to answer these clinical questions. However, the review indicates that non-invasive ventilation may be more beneficial than standard oxygen supplementation via a Venturi mask for pneumonia.

Noninvasive positive pressure ventilation: resource document for the National Association of EMS Physicians position statement

The National Association of EMS Physicians (NAEMSP) believes that noninvasive positive pressure ventilation (NIPPV) is an important treatment modality for the prehospital management of acute dyspnea. This document serves as a resource to the NAEMSP position on prehospital NIPPV.

Helmet continuous positive airway pressure vs oxygen therapy to improve oxygenation in community-acquired pneumonia: a randomized, controlled trial

OBJECTIVE

Our objective was to evaluate the efficacy of noninvasive continuous positive airway pressure (CPAP) delivered by helmet in improving oxygenation in comparison with oxygen therapy in community-acquired pneumonia (CAP).

METHODS

This was a multicenter, randomized, controlled trial enrolling patients with CAP admitted to an ED with moderate hypoxemic acute respiratory failure (ARF) (Pa(O(2))/Fi(O(2)) ratio > or = 210 and < or = 285). Patients were randomized to helmet CPAP or standard oxygen therapy (control group). The primary end point was the time to reach a Pa(O(2))/Fi(O(2)) ratio > 315. After reaching this value, patients randomized to CPAP were switched to oxygen, and the proportion of subjects who could maintain a Pa(O(2))/Fi(O(2)) ratio > 315 at 1 h was recorded.

RESULTS

Forty-seven patients were recruited: 20 randomized to CPAP and 27 to controls. Patients randomized to CPAP reached the end point in a median of 1.5 h, whereas controls reached the end point in 48 h (P < .001). The proportion of patients who reached the primary end point was 95% (19/20) among the CPAP group and 30% (8/27) among controls (P < .001). One hour after reaching the primary end point, 2/14 patients in the CPAP group maintained a Pa(O(2))/Fi(O(2)) value > 315.

CONCLUSIONS

CPAP delivered by helmet rapidly improves oxygenation in patients with CAP suffering from a moderate hypoxemic ARF. This trial represents a proof-of-concept evaluation of the potential usefulness of CPAP in patients with CAP.

Congenital and neonatal pneumonia

The greatest risk of death from pneumonia in childhood is in the neonatal period. It is estimated that pneumonia contributes to between 750000-1.2 million neonatal deaths annually, accounting for 10% of global child mortality. Congenital and neonatal pneumonias are often a difficult disease to identify and treat, with clinical manifestations often being non-specific. Many of the normal lung defences are compromised in the fetus and neonate, leading to an increased susceptibility to infection. The aetiology and epidemiology of congenital and neonatal pneumonias will depend on the clinical setting and population that the baby belongs to, the stage in the perinatal period, the gestational age of the baby and the definition of pneumonia. Diagnosis, treatment and prevention strategies are therefore also dependent on these factors, and will differ depending on the clinical setting. This review summarizes the current knowledge concerning congenital and neonatal pneumonia worldwide and discusses future directions in the prevention of the disease.

Neonatal pneumonia in developing countries

Pneumonia contributes to between 750,000 and 1.2 million neonatal deaths and an unknown number of stillbirths each year world wide. The aetiology depends on time of onset. Gram negative bacilli predominate in the first week of life, and Gram positive bacteria after that. Streptococcus pneumoniae probably causes about 25% of neonatal pneumonia. Interventions that would reduce mortality from this condition would have a large range of beneficial effects: improved maternal health, better management of other common neonatal conditions, and reduced long term childhood and adult morbidity.

The evaluation and management of hypoxemia in the chronic critically ill patient

Hypoxemia is a prevalent problem in the chronically critically ill patient. This article reviews the pathophysiologic mechanisms of hypoxemia in this patient population, discusses how oxygenation is evaluated, and reviews methods for delivery of oxygen. Other topics directly related to oxygen use, such as oxygen toxicity, heliox use, and portable oxygen devices, are included.

Acute respiratory failure in the HIV-seropositive patient

Since approximately 40% to 65% of patients with AIDS will develop pulmonary disease, HIV-seropositive patients represent a large cohort of immunosuppressed individuals with the potential to progress to respiratory failure requiring mechanical ventilation and admission to the intensive care unit. This article reviews the cause, pathophysiology, diagnostic approach, and management of acute respiratory failure requiring mechanical ventilation in HIV-seropositive patients. Prognostic factors and survival rates for episodes of respiratory failure are also discussed. In addition, an overview of acute respiratory failure in pediatric AIDS patients is presented.

Pneumocystis carinii pneumonia in cancer patients

Concern has been arisen about the recently reported increasing incidence of PCP in patients with cancer and the potential transmissibility of this infection. Whether or not there is an increase in the incidence of P. carinii infections, PCP should be considered in the differential diagnosis of pulmonary infiltrates in bone marrow transplant recipients, in patients with hematologic neoplasms and in patients with primary or metastatic brain neoplasms. Intensity of immunosuppression plays a crucial role, especially long-term (> 2 months) corticosteroid treatment. PCP is usually manifested clinically during augmentation or during tapering of corticosteroid dose. Thus, if the chest radiograph of a high-risk patient shows diffuse infiltrates, bronchoscopy and bronchoalveolar lavage should be done immediately. Treatment options are the same as for the AIDS population, except that TMP-SMX is tolerated better in non-AIDS patients. The role of supportive care, including mechanical ventilation in such patients should not be underestimated. Oral therapy with dapsone-trimethoprim or with atovaquone, can be as effective as conventional therapy in mild disease, permitting treatment on an outpatient basis. PCP is often preventable and our understanding has improved about when prophylaxis should be initiated. In the future, the emergence of new technologies for diagnosis and of new agents for treatment and prophylaxis, will bring us closer to the goal of controlling this serious infection.

CPAP mask management of varicella-induced respiratory failure

Pneumonia is a complication of primary varicella infection that occurs most commonly in adults and may lead to life-threatening respiratory failure. We report a case of varicella pneumonia with impending respiratory failure in which endotracheal intubation was averted by the use of CPAP mask ventilation with a favorable outcome.