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Author(s): Hitomi Hino[sup.1] , Yuka Suzuki[sup.2] , Eiichi Ishii[sup.1] , Mitsumasa Fukuda[sup.1] Author Affiliations: (1) Department of Pediatrics, Ehime University Graduate School of Medicine, Shitsukawa, 791-0295, Toon, EhimeJapan (2) Department [...], We describe an 11-year-old boy with nemaline myopathy who developed tension pneumothorax while undergoing noninvasive positive-pressure ventilation (NIPPV). The patient developed a persistent air leak after pleurodesis with minocycline hydrochloride and lowering of the NIPPV inspiratory pressure. He required additional respiratory support without the high airway pressures that may aggravate pneumothorax. We provided adequate respiratory support without increasing the positive airway pressure using biphasic cuirass ventilation (BCV), which moved the patient's chest wall by negative pressure. The air leak was resolved without any additional treatment. We should provide BCV for patients in whom surgery may have a risk of both extubation failure and postoperative complications before deciding on surgery.

Abstract: Adenosine is a potent neuromodulator in the central nervous system (CNS). The functional deterioration of adenosine A1 receptors in the CNS was reported to cause a failure of termination of seizures and to a lower seizure threshold of hyperthermia-induced seizures (HS) in childhood rats, which may contribute to adenosine-related convulsive disorders such as theophylline-associated seizures in childhood patients. In contrast to the inhibitory effect of adenosine A1 receptors, the function of adenosine A2A receptors remains controversial. To clarify the function of adenosine A2A receptors in childhood convulsive disorders associated to hyperthermia, we investigated the in vivo interaction between adenosine A2A receptors and their ligands in HS in childhood rats. Adenosine selective A2A receptor ligands were injected intraperitoneally before HS. We measured brain temperature at the onset of seizures and the mortality rate after HS. We found that brain temperature at seizure onset was significantly higher in the A2A receptor antagonist group compared with that in the control group (p <0.05), and there was no significant difference in mortality among the groups. In contrast, brain temperature at seizure onset was significantly lower in the A2A receptor agonist group compared with that in the control group (p <0.05), and mortality was significantly higher in the A2A agonist group compared with that in the control group (p <0.001). The activation of the adenosine A2A receptor might enhance seizures associated to hyperthermia in the childhood human brain, and be involved in the pathogenesis of sudden unexpected death in epilepsy (SUDEP) in childhood patients with convulsive disorders. [Copyright &y& Elsevier]

Theophylline-associated seizures (TAS) often progress to prolonged or treatment-resistant convulsions. Theophylline is a nonselective adenosine receptor antagonist. Adenosine is an endogenous anticonvulsant that can terminate seizures. Fever and young age have been reported to be risk factors for TAS. To elucidate the mechanism of TAS, we investigated the effect of theophylline and adenosine receptor ligands on hyperthermia-induced seizures in juvenile rats. The treatment dose of theophylline or control saline was injected intraperitoneally 1 h before hyperthermia-induced seizures. The seizure threshold in the theophylline group was significantly lower and seizure duration was significantly longer than those in the control group. The addition of a selective adenosine A1 receptor agonist and an adenosine kinase inhibitor completely counteracted the effects of theophylline. Moreover, a selective A1 antagonist caused a significantly longer seizure duration compared with the control. These findings suggest that blockage of the adenosine A1 receptor is the main cause of TAS. [ABSTRACT FROM AUTHOR]