Smith Keely, Gomez-Rubio Ana M, Harris Tomika S, Brooks Lauren E, Mosquera Ricardo A
Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
Case Rep Pediatr. 2016;2016:8359838. doi: 10.1155/2016/8359838. Epub 2016 Jun 21.
We present a case of a 17-year-old Hispanic male with Arnold-Chiari Type 1 [AC-Type 1] with syringomyelia, status post decompression, who complains of exercise intolerance, headaches, and fatigue with exertion. The patient was found to have diurnal hypercapnia and nocturnal alveolar hypoventilation. Cardiopulmonary testing revealed blunting of the ventilatory response to the rise in carbon dioxide (CO2) resulting in failure of the parallel correlation between increased CO2 levels and ventilation; the expected vertical relationship between PETCO2 and minute ventilation during exercise was replaced with an almost horizontal relationship. No new pathology of the brainstem was discovered by MRI or neurological evaluation to explain this phenomenon. The patient was placed on continuous noninvasive open ventilation (NIOV) during the day and CPAP at night for a period of 6 months. His pCO2 level decreased to normal limits and his symptoms improved; specifically, he experienced less headaches and fatigue during exercise. In this report, we describe the abnormal response to exercise that patients with AC-Type 1 could potentially experience, even after decompression, characterized by the impairment of ventilator response to hypercapnia during exertion, reflecting a complete loss of chemical influence on breathing with no evidence of abnormality in the corticospinal pathway.
我们报告一例17岁西班牙裔男性，患有1型阿诺德 - 奇亚里畸形（AC - 1型）并伴有脊髓空洞症，已行减压手术，主诉运动不耐受、头痛以及运动时疲劳。该患者被发现存在日间高碳酸血症和夜间肺泡通气不足。心肺功能测试显示，对二氧化碳（CO₂）升高的通气反应减弱，导致CO₂水平升高与通气之间的平行相关性丧失；运动期间呼气末二氧化碳分压（PETCO₂）与分钟通气量之间预期的垂直关系被几乎水平的关系所取代。通过磁共振成像（MRI）或神经学评估未发现脑干有新的病变来解释这一现象。该患者白天接受持续无创开放式通气（NIOV），夜间使用持续气道正压通气（CPAP），为期6个月。他的pCO₂水平降至正常范围，症状有所改善；具体而言，他运动时头痛和疲劳减轻。在本报告中，我们描述了AC - 1型患者即使在减压后仍可能出现的异常运动反应，其特征为运动时对高碳酸血症的通气反应受损，反映出化学因素对呼吸的影响完全丧失，且皮质脊髓通路无异常证据。
