Role of the central nervous system in the adult respiratory distress syndrome

Abstract

The CNS might play an important pathophysiologic role in the induction of the adult respiratory distress syndrome (ARDS). Post-traumatic development of cerebral microthromboses seems to be a major feature. To test this hypothesis, we subjected Wistar rats with postburn ARDS to the following microneurosurgical procedures in an attempt to morphologically detect modifications in the evolving pattern: a) anterior (AH) or posterior (PH) hypothalamus nuclei stereotaxic electrolytic lesion; b) intracerebroventricular microinjections of phenoxybenzamine (PB)-50, μg propranolol-0.5 μg, cocaine-5 μg, epinephrine-0.5 μg, carbachol(CA)-5 μg, pirilamine-20 μg, cimetidine-30 μg, lidocaine-20 μg, atropine (AT)-40 μg; c) intra-AH microinjections of CA-10 μg, AT-20 μg; and d) intra-PH microinjections of PB-10 μg, norepinephrine-0.05 μg. The results showed that the alpha-adrenergic components of PH induce a potentiation in ARDS whereas the cholinergic components of AH seem to attenuate this syndrome. This work suggests that a damaged CNS may suffer cybernetic derangements as to induce it to generate inappropriate adaptative responses that can result in the development of ARDS.