Lawson-Smith Pia, Jansen Erik C, Hilsted Linda, Hyldegaard Ole
Department of Anesthesia, Center of Head and Orthopedics, Rigshospitalet, Blegdamsvej, Copenhagen, Denmark.
Scand J Trauma Resusc Emerg Med. 2010 Jun 15;18:32. doi: 10.1186/1757-7241-18-32.
Hydrogen cyanide (HCN) and carbon monoxide (CO) may be important components of smoke from fire accidents. Accordingly, patients admitted to hospital from fire accidents may have been exposed to both HCN and CO. Cyanide (CN) intoxication results in cytotoxic hypoxia leading to organ dysfunction and possibly death. While several reports support the use of hyperbaric oxygen therapy (HBO) for the treatment of severe CO poisoning, limited data exist on the effect of HBO during CN poisoning. HBO increases the elimination rate of CO haemoglobin in proportion to the increased oxygen partial pressure and animal experiments have shown that in rats exposed to CN intoxication, HBO can increase the concentration of CN in whole blood.
The purpose of the present study was to determine whole blood CN concentrations in fire victims before and after HBO treatment.
The patients included were those admitted to the hospital because of CO intoxication, either as fire victims with smoke inhalation injuries or from other exposures to CO. In thirty-seven of these patients we measured CN concentrations in blood samples, using a Conway/microdiffusion technique, before and after HBO. The blood samples consisted of the remaining 2 mL from the arterial blood gas analysis. CN concentration in blood from fire victims was compared to 12 patients from non-fire accidents but otherwise also exposed to CO intoxication.
The mean WB-CN concentration before patients received HBO did not differ significantly between the two groups of patients (p = 0.42). The difference between WB-CN before and after HBO did not differ significantly between the two groups of patients (p = 0.7). Lactate in plasma before and after did not differ significantly between the two groups of patients. Twelve of the 25 fire patients and one of the non-fire patients had been given a dose of hydroxycobalamin before HBO.
CN concentrations in blood from patients admitted to hospital with CO intoxication and smoke inhalation exposure did not differ significantly from controls. Accordingly, we were not able to detect any changes in CN concentrations in blood after treatment with HBO.
ClinicalTrials.gov identifier: NCT00280579.
氰化氢（HCN）和一氧化碳（CO）可能是火灾事故烟雾中的重要成分。因此，因火灾事故入院的患者可能同时接触过HCN和CO。氰化物（CN）中毒会导致细胞毒性缺氧，进而引发器官功能障碍甚至可能导致死亡。虽然有几份报告支持使用高压氧疗法（HBO）治疗重度CO中毒，但关于HBO在CN中毒时的效果的数据有限。HBO会随着氧分压的升高按比例增加碳氧血红蛋白的清除率，动物实验表明，在暴露于CN中毒的大鼠中，HBO会增加全血中CN的浓度。
本研究的目的是测定火灾受害者在HBO治疗前后全血中的CN浓度。
纳入的患者为因CO中毒入院的患者，包括因吸入烟雾受伤的火灾受害者或其他接触CO的情况。在其中37例患者中，我们使用康威/微扩散技术在HBO治疗前后测量了血样中的CN浓度。血样取自动脉血气分析剩余的2 mL血液。将火灾受害者的血液CN浓度与12例非火灾事故但同样接触CO中毒的患者进行比较。
两组患者在接受HBO治疗前的平均全血CN浓度无显著差异（p = 0.42）。两组患者HBO治疗前后全血CN浓度的差异无统计学意义（p = 0.7）。两组患者血浆中乳酸水平在治疗前后也无显著差异。25例火灾患者中有12例和1例非火灾患者在HBO治疗前接受了一剂羟钴胺素。
因CO中毒和吸入烟雾暴露入院的患者血液中的CN浓度与对照组无显著差异。因此，我们未能检测到HBO治疗后血液中CN浓度的任何变化。
ClinicalTrials.gov标识符：NCT00280579。
