Distribution and Suspected Causes of Methemoglobinemia at an Academic Medical Center

Supplementary file 1: Data for methemoglobin concentrations in whole blood specimens performed at the University of Iowa Hospitals and Clinics from May 1, 2009 to June 22, 2023. The data elements for the “All Values” tab (which contains all methemoglobin values in the above timeframe) include: deidentified patient number, legal sex in the electronic medical record, patient age in years at time of methemoglobin measurement (greater than 89 years expressed as ">89"), location type (outpatient or inpatient) for where methemoglobin measurement was made, quantitative methemoglobin value (%), methemoglobin category (0.0-3.0%, 3.1-4.9%, 5.0-9.9%, and 10+%), and pediatric/adult at time of testing (pediatric defined as < 18 years old). The data elements for the “Episodes with MetHb >=3.1%” field (which contains only those episodes of care with a methemoglobin concentrations of 3.1% or higher) include: deidentified patient number, legal sex in the electronic medical record, patient age in years at time of methemoglobin measurement (greater than 89 years expressed as ">89"), location type (outpatient or inpatient) for where methemoglobin measurement was made, methemoglobin cause category from chart review, highest quantitative methemoglobin value (%) during episode of care, methemoglobin category (0.0-3.0%, 3.1-4.9%, 5.0-9.9%, and 10+%), pediatric/adult (pediatric defined as < 18 years old), asymptomatic during episode (yes/no), cardiovascular symptoms during episode (yes/no), cough during episode (yes/no), cyanosis during episode (yes/no), death during episode of care (yes/no), dizziness and/or loss of balance during episode (yes/no), edema during episode (yes/no), fatigue during episode (yes/no), gastrointestinal pain during episode (yes/no), nausea/vomiting during episode (yes/no), respiratory difficulties during episode (yes/no). Supplementary file 2: Data for methemoglobin concentrations in whole blood specimens performed at the University of Iowa Hospitals and Clinics from January 1, 1996 to April 30, 2009. The data elements for the “All Values” tab (which contains all methemoglobin values in the above timeframe) are the same as the “All Values” tab in Supplemental file 1. The data elements for the “Episodes with MetHb >=10.0%” field contain only those episodes of care with a methemoglobin concentrations of 10.0% or higher. Data elements are the same as those in the “Episodes with MetHb >=3.1%” tab in Supplemental file 1.

补充文件1：2009年5月1日至2023年6月22日期间，爱荷华大学医院与诊所（University of Iowa Hospitals and Clinics）检测的全血标本高铁血红蛋白（methemoglobin, MetHb）浓度数据。其中“所有数值（All Values）”标签页收录了该时间段内全部高铁血红蛋白检测值，其数据字段包括：去标识化患者编号、电子病历中的法定性别、高铁血红蛋白检测时的患者年龄（年龄大于89岁者标注为“>89”）、检测实施所在的场所类型（门诊或住院）、定量高铁血红蛋白值（%）、高铁血红蛋白分类（0.0-3.0%、3.1-4.9%、5.0-9.9%及10+%），以及检测时患者的年龄分层（儿童或成人，儿童定义为<18岁）。
“MetHb≥3.1%事件（Episodes with MetHb >=3.1%）”标签页仅收录高铁血红蛋白浓度≥3.1%的诊疗事件，其数据字段包括：去标识化患者编号、电子病历中的法定性别、高铁血红蛋白检测时的患者年龄（年龄大于89岁者标注为“>89”）、检测实施所在的场所类型（门诊或住院）、经病历回顾确定的高铁血红蛋白病因分类、本次诊疗事件期间的最高定量高铁血红蛋白值（%）、高铁血红蛋白分类（0.0-3.0%、3.1-4.9%、5.0-9.9%及10+%）、检测时的患者年龄分层（儿童或成人，儿童定义为<18岁）、本次事件期间是否无症状（是/否）、本次事件期间是否存在心血管症状（是/否）、本次事件期间是否存在咳嗽（是/否）、本次事件期间是否存在发绀（是/否）、本次诊疗事件期间患者是否死亡（是/否）、本次事件期间是否出现头晕及/或平衡失调（是/否）、本次事件期间是否存在水肿（是/否）、本次事件期间是否存在乏力（是/否）、本次事件期间是否存在胃肠道疼痛（是/否）、本次事件期间是否出现恶心/呕吐（是/否）、本次事件期间是否存在呼吸困难（是/否）。
补充文件2：1996年1月1日至2009年4月30日期间，爱荷华大学医院与诊所检测的全血标本高铁血红蛋白浓度数据。其中“所有数值（All Values）”标签页的数据字段与补充文件1的“所有数值（All Values）”标签页完全一致。“MetHb≥10.0%事件（Episodes with MetHb >=10.0%）”标签页仅收录高铁血红蛋白浓度≥10.0%的诊疗事件，其数据字段与补充文件1的“Episodes with MetHb >=3.1%”标签页完全相同。