Outcome of invasive mechanical ventilation in cancer patients: Intubate or not to intubate a patient with cancer.

PURPOSE: The outcome of cancer patients who undergo mechanical ventilation has been grim. However, it has lately become more promising, creating hesitation when approaching the decision to intubate a cancer patient. Therefore, the main goal was to find some factors that could predict mortality. MATERIAL AND METHODS: Studies were selected on the basis of their information wholeness, the year done, patients' number, participating country, underlying hematological or nonhematological malignancies, ventilation duration, ICU survival, hospital survival, long term survival, disease activity, and other contributing factors. RESULTS: Twenty-two studies were included which accrued 3115 patients. The average ICU survival was 32.4%, and long-term survival was 10.2%. Over the years, the outcome of cancer patients undergoing mechanical ventilation has improved. The most important predicting factors are: The respiratory failure etiology, the performance status, the disease activity, and the SOFA score. CONCLUSIONS: The aforementioned predicting factors could be used when approaching the decision to intubate. When in doubt, we should give the benefit to the patient, proceed to intubate and reevaluate progress daily and in doing so, we would suggest to use the trends in SOFA score and weaning index to assess success or failure of invasive mechanical ventilation.

Pulmonary alveolar proteinosis: a case report and world literature review.

Pulmonary alveolar proteinosis (PAP) is a lung disorder which was first described in 1958 by Rosen et al. and is indeed rare disease with a prevalence of 0.1 per 100,000 individuals. PAP is characterized by abnormal accumulation of pulmonary surfactant in the alveolar space, which impairs gas exchange leading to a severe hypoxemia. Pulmonary surfactant is an insoluble proteinaceous material that is rich in lipids and stains positive with periodic acid-Schiff (PAS). The most common type of PAP is the so-called autoimmune or idiopathic type. It has been hypothesized that deficiency in granulocyte macrophage-colony stimulating factor (GM-CSF), as a result of the anti-GM-CSF antibody production, is strongly related to impaired surfactant recycling that leads to the accumulation of surfactant in the alveolar space. Its clinical course is variable from spontaneous remission in the best case scenario, going through the entire spectrum of disease severity, towards fatal respiratory failure. Whole lung lavage has been the gold standard therapy in PAP until the advent of GM-CSF. Although the first case was reported to be idiopathic, subsequent analysis revealed that Pneumocystis jirovecii, silica, and other inhalational toxins were able to trigger this reaction. In this study, we report the case of a 52-year-old man who developed PAP syndrome after a 2-year exposure to silica dust. Our review of the world literature that includes 363 cases reported until now, reflects the evolution of science and technology in determining different aetiologies and diagnostic tests that lead to an improved perspective in the life of these patients.

The weaning index as predictor of weaning success.

BACKGROUND: The quest to obtain an accurate way to predict success when weaning a patient from mechanical ventilation continues. The established parameters such as tidal volume (Vt), respiratory rate (f), negative inspiratory force (NIF), vital capacity (VC), and minute ventilation (V) have not predicted weaning accurately. The frequency-to-tidal volume ratio (f/Vt), or rapid shallow breathing index (RSBI) is a good predictor of weaning success if the value is low, but not when the value approximates 105. Because of the aforementioned, we decided to add 2 corrective factors to the RSBI. The first one was elastance index (EI = peak pressure/NIF) and the second one, the ventilatory demand index (VDI = minute ventilation/10). The result of the product of the RSBI × EI × VDI was called the weaning index (WI). METHODS: In order to assess the discriminatory power of WI, we obtained weaning parameters and calculated WI for 59 patients in our intensive care unit and extubated them if RSBI was ≤105. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and receiver-operating characteristics (ROC) curves were obtained. The results were compared with the previous studies involving the RSBI. RESULTS: The WI sensitivity was 98%, specificity was 89%, PPV was 95%, NPV was 94%, and area under the ROC curve was 95.9. CONCLUSIONS: The WI is a simple and reproducible parameter that integrates breathing pattern, compliance, inspiratory muscle strength, and ventilatory demand and is the most accurate predictor of weaning success.

The lung permeability index: a feasible measurement of pulmonary capillary permeability.

BACKGROUND: We performed this study to determine the pulmonary capillary permeability (PCP) measuring radiolabeled human serum albumin leakage into the lung. The objective was to use PCP to differentiate between cardiogenic and non-cardiogenic pulmonary edema etiologies. METHODS: We conducted this study in 10 patients admitted to the intensive care unit who had recently developed bilateral pulmonary infiltrates and required hemodynamic monitoring. In these patients we determined the association among the lung permeability index, cardiac output, pulmonary capillary wedge pressure, myocardial performance index, and the protein content of the bronchoalveolar lavage as expressed by bronchoalveolar lavage (BAL) total protein and BAL-to-serum protein ratio. Twenty mCi of technetium-labeled albumin was injected and measure in the heart and the lung at 10 and 180 min post-injection. Lung and heart uptake ratios as well as the lung permeability index were calculated. RESULTS: We found a good correlation between the lung permeability index and both the myocardial performance index (cardiac output/pulmonary capillary wedge pressure) and the total protein content of the bronchoalveolar lavage fluid. CONCLUSION: The lung permeability index is a feasible, noninvasive estimation of the pulmonary capillary permeability.