Early activation of inflammation and clotting in the preterm lamb with neonatal RDS: Comparison of conventional ventilation and high frequency oscillatory ventilation

• Published in: Pediatric research Vol. 50; no. 5; pp. 650 - 657
• Main Authors: JAARSMA, Anneke S, BRAAKSMA, Margriethe A, GEVEN, Wil B, VAN OEVEREN, Wim, OETOMO, Sidarto Bambang
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD Lippincott Williams & Wilkins 01.11.2001
• Subjects: Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Animals; Animals, Newborn; Biological and medical sciences; Blood Coagulation; Bronchoalveolar Lavage Fluid; Disease Models, Animal; Emergency and intensive care: neonates and children. Prematurity. Sudden death; Humans; Infant, Newborn; Inflammation - physiopathology; Intensive care medicine; Medical sciences; Respiration; Respiratory Distress Syndrome, Newborn - physiopathology; Sheep; Premature; Pathophysiology; Respiratory disease; Coagulation; Inflammation; Artificial ventilation; Lamb; Vertebrata; Mammalia; Newborn animal; Secondary effect; Sheep; Respiratory distress; Early; Artiodactyla; Biological effect; High frequency ventilation; Ungulata; Comparative study
• ISSN: 0031-3998; 1530-0447
• DOI: 10.1203/00006450-200111000-00019

In neonatal respiratory distress syndrome activation of inflammation and clotting is demonstrated. High frequency oscillatory ventilation (HFOV) is considered to be less damaging to the human preterm lung, resulting in less activation of inflammation and clotting compared with conventional ventilation (CV). To assess the sequence of events of activation of inflammation and clotting and to compare the impact of HFOV to CV, we ventilated preterm lambs delivered by cesarean section at 132 d gestational age (term 145 d) for 8 h by CV (n = 10) or HFOV (n = 11). Fifteen minutes after birth and at 2-h intervals thereafter blood samples, from umbilical catheters, were analyzed for AP50 (complement activation), number of polymorphonuclear leukocytes, beta-glucuronidase, platelet function, activated partial thromboplastin time, thrombin time and thrombin inhibition, and bronchoalveolar lavage fluid was analyzed for elastase, thrombin and protein. We found complement activation, low number of polymorphonuclear leukocytes and high levels of beta-glucuronidase already at 15 min after birth. Within 2 to 4 h after birth platelet function deteriorated, activated partial thromboplastin time prolonged, and thrombin inhibition decreased. Activation of inflammation and clotting in the lungs was demonstrated by increased levels of elastase and thrombin in bronchoalveolar lavage fluid. In the HFOV group, AP50 remained significantly higher than in the CV group, reflecting less complement activation, and platelet function analysis remained significantly lower, reflecting better platelet function. We conclude that systemic activation of inflammation can be found in the ventilated preterm lamb with respiratory distress syndrome within 15 min after birth. Afterward, or due to activation of inflammation, clotting is activated. HFOV possibly attenuates activation of inflammation.