Role of nebulized heparin inhalation on mechanically ventilated critically ill patients

Abstract

Mechanical ventilation is one of the most important tools in the treatment of respiratory failure in critically ill patients, but it may cause lung injury and inflammatory response in the whole body. The aim of our study was to justify the effect of nebulized heparin on morbidity, oxygenation parameters, lung mechanics, and mortality in mechanically ventilated critically ill patients who are assumed to require mechanical ventilation for more than 48 h for different indications. This study was conducted on 50 ICU patients who were in need of mechanical ventilation for more than 48 h. They were grouped randomly into two groups. One of the two groups was given nebulized heparin sodium until weaning or for a maximum of 14 days. Patients with coagulopathy or scheduled for any invasive intervention that may lead to bleeding were excluded. In addition, patients who were weaned or who died before day 4of admission were also excluded. Both groups were followed up for a maximum of 28 days. The study medication was reduced or withheld if any significant bleeding occurred. The endpoint results were primary oxygenation parameters [mainly arterial oxygen partial pressure (PaO2)/inspired oxygen fraction (FIO2)] and ventilator-free days. All other data were recorded and analyzed to find out the adverse positive effect of heparin nebulization. Data analysis revealed that the following data showed no statistically significant difference within groups over time or between the two groups: PaCO2, pH, PaO2, HCO3, SO2, PaO2/FIO2, FIO2×mean airway pressure/PaO2, peak inspiratory pressure, mean airway pressure, tumor necrosis factor α , systolic blood pressure, diastolic blood pressure, hemoglobin, hematocrit value, white blood cells count, platelet count, prothrombin concentration, international normalized ratio, presence of bloody sputum, ICU-free days at day 28, ventilator-free days at day 28, acute renal failure-free days at day 28, vasopressor-free days at day 28, and mortality and sputum culture results at day 4. However, the following data showed a statistically significant difference in the heparin-treated group: plateau pressure showed a statistically significant decrease between days 1 and 4 in the heparin-treated group (P=0.003) and a statistically significant difference when we compared the percentage change between the two groups (P=0.015). Compliance rate showed a statistically significant increase between days 1 and 4 in the heparin-treated group (P=0.019) but when we compared the percentage change between the two groups the difference was not statistically significant (P=0.256). Activated partial thromboplastin time showed a statistically significant increase between days 1 and 4 in the heparin-treated group (P=0.001), but when we compared the percentage change between the two groups the difference was not statistically significant (P=0.153). No cases of heparin-induced thrombocytopenia was noted in the heparin-treated group, nor was there major bleeding or need for blood transfusion related to the tested medication in this group. We recommend nebulized heparin as a safe drug that has a favorable effect in patients receiving mechanical ventilation especially with reduced compliance as in cases of acute respiratory distress syndrome.