吐血（呕血）是指呕吐物中有大量血液。吐出物中的小血丝或血斑可能来自牙齿、口腔或咽喉，这种情况一般不视为吐血。呕吐物中的血液可能为鲜红色，也可能呈黑色或深棕色，像咖啡渣一样。
吞入的血液（如因鼻出血或用力咳嗽所致）可能导致出现血性呕吐物，但实际上，吐血通常意味着某种更严重的状况并且需要立即就医。因消化性（胃或十二指肠）溃疡或血管撕裂所致的上消化道（口腔、食管、胃和小肠上部）出血，是常见的吐血原因。
如果因吐血导致站起身后头晕、呼吸浅快或出现其他休克体征，请拨打 911 或本地急救电话。
请拨打 911 或寻求紧急医疗协助
如果吐血导致下列失血失血或休克的症状和体征，请拨打 911：
- 浅快呼吸
- 站起身后感觉头晕或头重脚轻
- 视力模糊
- 昏厥
- 意识模糊
- 恶心
- 皮肤冰凉、黏湿、苍白
- 尿量少
请立即就医
如果您注意到呕吐物带血或开始吐血，请要求人开车送您去急诊室。重要的是要快速确定出血的根本原因并防止更严失血和其他并发症，包括死亡。
显示参考文献
- Gastrointestinal (GI) bleeding. National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/digestive-diseases/gastrointestinal-bleeding. Accessed Feb. 15, 2022.
- Rockey DC. Causes of upper gastrointestinal bleeding in adults. https://www.uptodate.com/contents/search. Accessed Feb. 15, 2022.
- Feldman M, et al., eds. Gastrointestinal bleeding. In: Sleisenger and Fordtran's Gastrointestinal and Liver Disease: Pathophysiology, Diagnosis, Management. 11th ed. Elsevier; 2021. https://www.clinicalkey.com. Accessed Feb. 15, 2022.
- Kliegman RM. Major symptoms and signs of digestive tract disorders. In: Nelson Textbook of Pediatrics. 21st ed. Elsevier; 2020. https://www.clinicalkey.com. Accessed Feb. 15, 2022.
- Shock. American College of Emergency Physicians. https://www.emergencyphysicians.org/article/know-when-to-go/shock. Accessed Feb. 15, 2022.
- Picco MF (expert opinion). Mayo Clinic. Feb. 23, 2022.
Original article: https://www.mayoclinic.org/zh-hans/symptoms/vomiting-blood/basics/causes/sym-20050732