Diving Medical Center, Royal Netherlands Navy, PO Box 10000, 1780 CA, Den Helder, The Netherlands.
J Neurosci Methods. 2011 Jan 15;194(2):336-41. doi: 10.1016/j.jneumeth.2010.10.028. Epub 2010 Nov 11.
Cerebral arterial gas embolism is a risk in diving and occurs as a complication in surgery and interventional radiology. Swine models for cerebral arterial gas embolism have been used in the past. However, injection of air into the main artery feeding the pig brain - the ascending pharyngeal artery - might be complicated by the presence of the carotid rete, an arteriolar network at the base of the brain. On the other hand, anastomoses between external and internal carotid territories are present in the pig. In order to determine the most appropriate vessel for air injection, we performed experiments in which air was injected into either the ascending pharyngeal artery or the external carotid artery. We injected 0.25 ml/kg of room air selectively into the ascending pharyngeal artery or the external carotid artery of 35-40 kg Landrace pigs (n=8). We assessed the effect on cerebral metabolism by measuring intracranial pressure, brain oxygen tension and brain glucose and lactate concentrations using cerebral microdialysis. Intracranial pressure and brain oxygen tension changed significantly in both groups, but did not differ between groups. Brain lactate increased significantly more in pigs in which air was injected into the ascending pharyngeal artery. Intracranial pressure, brain oxygen tension and brain lactate correlated after injection of air into the ascending pharyngeal artery, but not after injection into the external carotid artery. Our model is suitable for investigation of cerebral arterial gas embolism. The ascending pharyngeal artery is the most appropriate vessel for air injection.
脑动脉气体栓塞是潜水时的风险，并在手术和介入放射学中作为并发症出现。过去曾使用过脑动脉气体栓塞的猪模型。然而，将空气注入供应猪脑的主要动脉——咽升动脉——可能会因颈动脉网（大脑底部的小动脉网络）的存在而变得复杂。另一方面，猪的颈外和颈内动脉之间存在吻合。为了确定最适合注气的血管，我们进行了实验，将空气选择性地注入咽升动脉或颈外动脉。我们将 0.25 毫升/公斤的室温空气注入 35-40 公斤长白猪（n=8）的咽升动脉或颈外动脉。我们通过使用脑微透析测量颅内压、脑氧分压以及脑葡萄糖和乳酸浓度来评估脑代谢的影响。两组的颅内压和脑氧分压均显著改变，但组间无差异。注入咽升动脉的空气后，猪脑的乳酸明显增加。注入咽升动脉后，颅内压、脑氧分压和脑乳酸之间存在相关性，但注入颈外动脉后则没有。我们的模型适合研究脑动脉气体栓塞。咽升动脉是最适合注气的血管。
