Nebulized Heparin for Prevention of Acute Lung Injury in Adult Patients Suffering Smoke Inhalation Injury: A Randomized Controlled Trial

Abstract Background Nebulized heparin (NH) has been used for treatment of inhalation injury- induced acute respiratory distress syndrome (ARDS) but its benefit for prevention of severe ARDS in those patients is not known. Aim of the Work The aim of this study was to examine the effect of NH on prevention of severe ARDS and on survival in patients suffering inhalation injury. Methods Eighty-eight adults suffering inhalation injury were randomized to receive 5,000 IU of heparin in 3 ml normal saline (n = 44) or to normal saline only (n = 44) by nebulization every 4 hours until successful extubation or death, whichever was earlier, to a maximum of 14 days. Primary outcomes were occurrence of severe ARDS (PaO2/FiO2 ratio <100) and survival to ICU discharge. Secondary outcomes were failed weaning from mechanical ventilation (reintubation in 48 hours after extubation) and occurrence of heparin-related side effects. Results There was no statistically significant difference between both groups as regards occurrence of severe ARDS (p-value =.233), mortality (p-value = .354), reintubation within 48 hours (p-value = .419) or thrombocytopenia (p-value = .777). None of the patients developed abnormal prolongation of prothrombin time (PTT). Estimated marginal mean PaO2/FiO2 ratio was significantly higher (p-value < .001) and mean platelet count was significantly lower (p-value = .005) in the nebulized heparin group, with no statistically significant difference in mean PTT (p-value = .074). Conclusions Nebulized heparin was associated with improved oxygenation but was did not reduce the incidence of severe ARDS, failed weaning from mechanical ventilation or mortality in patients suffering inhalation injury. Nebulized heparin had no effect on prothrombin time but could be associated with clinically unimportant reduction in platelet count.