Sessler C N
Department of Medicine, Medical College of Virginia, Richmond 23298-0050.
Am J Med. 1990 Jun;88(6):567-76. doi: 10.1016/0002-9343(90)90519-j.
To examine the predisposing factors, clinical and laboratory characteristics, management, course, and outcome of consecutive cases of theophylline toxicity in an outpatient setting.
Toxicology records and hospital charts of consecutive patients with a serum theophylline concentration (STC) greater than 30 mg/L (167 mumol/L) identified in the emergency departments (EDS) of a University Medical Center and a Veterans Administration Medical Center were reviewed.
Ten percent and 2.8% of 5,557 consecutive STCs measured in the EDs over 2 years were greater than 20 mg/L (111 mumol/L) and greater than 30 mg/L (167 mumol/L), respectively. One hundred sixteen cases with STC greater than 30 mg/L were identified. Fourteen (12%) and 102 (88%) were due to acute overdose and chronic overmedication, respectively. Principal predisposing factors included patient and/or physician dosing errors and conditions or medications that reduce theophylline clearance. One or more toxic manifestations were present in 109 (94%) cases. Fifty percent of patients had mild toxicity, 38% had moderate toxicity, and 7% had severe or life-threatening toxicity. Seven (6%) patients died when STC was still in the toxic range and/or as a result of toxicity. Acute overdose was associated with higher peak STC (p less than 0.001), younger age (p less than 0.01), and greater mortality (p less than 0.05) than chronic overmedication. Peak STC correlated significantly with the severity of toxicity for patients with acute overdose (p less than 0.01) but not for patients with chronic overmedication. All three patients with acute overdose and fatal toxicity had peak STCs greater than 100 mg/L (555 mumol/L) and fulminant toxicity, whereas the four patients with chronic overmedication who died during toxicity had peak STCs in the 40 to 60 mg/L (222 to 333 mumol/L) range and most died of respiratory failure rather than directly from toxicity. Patients with acute overdose who had the delayed onset of severe or life-threatening toxicity and/or died from toxicity were accurately identified using previously published criteria for prophylactic charcoal hemoperfusion. In contrast, the predictive value of the criteria applied to patients with chronic overmedication was poor. Two patients with acute overdose underwent charcoal hemoperfusion, but died. No patient with chronic overmedication received charcoal hemoperfusion.
Toxic-range STCs are relatively common in the ED population, occur primarily as a result of patient and physician dosing errors, and cause a broad range of toxic manifestations of varying severity. Peak STC correlates with the severity of toxicity and outcome for acute overdose but not chronic overmedication intoxication. Previously published criteria for prophylactic charcoal hemoperfusion accurately identify patients with acute overdose but not patients with chronic overmedication at risk for serious complications and death.
研究门诊环境下连续茶碱中毒病例的诱发因素、临床及实验室特征、处理方法、病程及转归。
回顾某大学医学中心及退伍军人管理局医疗中心急诊科中血清茶碱浓度（STC）大于30 mg/L（167 μmol/L）的连续患者的毒理学记录及医院病历。
在两年内急诊科连续检测的5557份STC中，分别有10%和2.8%大于20 mg/L（111 μmol/L）及大于30 mg/L（167 μmol/L）。共识别出116例STC大于30 mg/L的病例。其中14例（12%）为急性过量用药，102例（88%）为慢性用药过量。主要诱发因素包括患者和/或医生的用药错误以及降低茶碱清除率的疾病或药物。109例（94%）患者出现一种或多种中毒表现。50%的患者为轻度中毒，38%为中度中毒，7%为重度或危及生命的中毒。7例（6%）患者在STC仍处于中毒范围时死亡和/或因中毒死亡。与慢性用药过量相比，急性过量用药的STC峰值更高（p<0.001）、年龄更小（p<0.01）且死亡率更高（p<0.05）。急性过量用药患者的STC峰值与中毒严重程度显著相关（p<0.01），而慢性用药过量患者则不然。3例急性过量用药且中毒致死的患者STC峰值均大于100 mg/L（555 μmol/L）且为暴发性中毒，而4例慢性用药过量且在中毒期间死亡的患者STC峰值在40至60 mg/L（222至333 μmol/L）之间，多数死于呼吸衰竭而非直接死于中毒。采用先前发表的预防性活性炭血液灌流标准能准确识别急性过量用药且出现严重或危及生命中毒延迟发作和/或死于中毒的患者。相比之下，应用于慢性用药过量患者的标准预测价值较差。2例急性过量用药患者接受了活性炭血液灌流，但仍死亡。无慢性用药过量患者接受活性炭血液灌流。
中毒范围的STC在急诊科患者中相对常见，主要因患者和医生用药错误导致，可引起一系列严重程度各异的中毒表现。STC峰值与急性过量用药的中毒严重程度及转归相关，而与慢性用药过量中毒无关。先前发表的预防性活性炭血液灌流标准能准确识别急性过量用药患者，但不能识别有严重并发症和死亡风险的慢性用药过量患者。
