一、观察血便的性质:众所周知上消化道出血(称上消血)其血便呈黑色或柏油样便,下消化道出血(称下消血)呈暗红色或鲜红色。医生必须亲自观察血便的性状,不能单凭病人或家属的诉述。横结肠中段以 First, observe the nature of bloody stools: It is well known that upper gastrointestinal bleeding (called anti-bloody) black or tarry stool, lower gastrointestinal bleeding (called anti-bloody) was dark red or bright red. Doctors must observe the traits of bloody stools themselves and can not rely solely on the complaints of patients or their families. The middle part of the transverse colon