Inhaled Thrombolytics Reduce Lung Microclot and Leukocyte Infiltration After Acute Blood Loss
| Autor: | William F. Dovi, Melissa L. Bates, Robert L. Conhaim, Kal E. Watson |
|---|---|
| Rok vydání: | 2014 |
| Předmět: |
Male
Pulmonary Circulation Resuscitation Pathology medicine.medical_specialty Acute Lung Injury Hemorrhage Blood volume Critical Care and Intensive Care Medicine Fibrinogen Tissue plasminogen activator Fibrin Rats Sprague-Dawley Fibrinolytic Agents Administration Inhalation medicine Animals Blood Volume Microscopy Confocal Lung biology Inhalation business.industry medicine.disease Immunohistochemistry Rats Disease Models Animal medicine.anatomical_structure Neutrophil Infiltration Anesthesia Emergency Medicine biology.protein Fibrin Clot Lysis Time Pulmonary Embolism business Infiltration (medical) medicine.drug |
| Zdroj: | Shock. 41:528-536 |
| ISSN: | 1073-2322 |
| DOI: | 10.1097/shk.0000000000000149 |
| Popis: | We showed previously that a 30% blood loss in rats, without resuscitation, caused significant accumulation of microthrombi and leukocytes within the pulmonary circulation by 24 h. We hypothesized that the microthrombi formed spontaneously as a consequence of hemorrhage-induced stasis within the low-pressure pulmonary circuit and that the leukocytes were attracted to them. This suggested that elimination of the microthrombi, using an inhaled thrombolytic agent, could prevent the neutrophil sequestration after blood loss. To test this hypothesis, we removed 30% of the calculated blood volume from isoflurane-anesthetized, male Sprague-Dawley rats (350-500 g) over 5 min and allowed them to recover. Six hours later, we re-anesthetized the rats and nebulized tissue plasminogen activator (80 or 320 µg/kg), lactated Ringer's solution (LRS), or ipratropium bromide (i-bromide) into their lungs. We used i-bromide as a control after we discovered that nebulized LRS had thrombolytic properties. At 24 h, we removed and fixed the lungs and prepared sections for immunohistochemistry using antibodies against fibrinogen (microthrombi) and CD16 (leukocytes). Digital images of each section were obtained using a confocal microscope. Pixel counts of the images showed significantly less accumulation of microthrombi and leukocytes in lungs nebulized with tissue plasminogen activator or LRS than in non-nebulized lungs or in lungs nebulized with i-bromide (P ≤ 0.05). Lactated Ringer's solution becomes positively charged when nebulized (unlike i-bromide), suggesting that it eliminated microthrombi by fibrin depolymerization. We confirmed this using an in vitro assay. Our results demonstrate that lyses of microthrombi that accumulate in the lung after acute blood loss prevent subsequent leukocyte sequestration. |
| Databáze: | OpenAIRE |
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