Blood and guts
The gut technically extends from the mouth to the anus and we all know what normally goes in and what normally comes out and it isn’t blood. Blood coming out above or below is abnormal and potentially very serious.
Starting with problems at the top, it is possible to see small flecks of blood with vigorous vomiting as perhaps a bad case of food poisoning or after a hard night drinking. This can be a frightening feature but it is normally caused by a slight tear at the base of the gullet induced by the strain of vomiting and it is a relatively innocent and short-lived problem. Far more serious is a bleed from swollen veins at the base of the gullet. These veins resemble varicose veins in the legs and develop in association with liver damage, often alcohol-induced over some years. If one of these bursts then the flow of blood can be dramatic, producing large quantities of vomited unaltered blood which is life-threatening and needs emergency hospital treatment.
Moving down from the gullet and into the stomach, there is always the possibility of a stomach ulcer eroding into a blood vessel in the stomach wall. The acidic contents of the stomach alter the blood and it emerges in vomit resembling coffee grounds. This is also a serious emergency. If the person survives long enough for the blood to go through the bowel, then it emerges as a black tarry material.
Bleeding from the actual bowel downstream from the stomach is not likely to emerge as vomit but will emerge as black tarry material in the loo. This is a sign of major internal bleeding into the bowel and, if it were visible, it would cause serious alarm to everyone because the volume of blood loss can be substantial. Internal bleeding may be under-estimated until it may be too late to help and it is crucial to have someone on board who has been taught how to monitor vital signs if a case is suspected – the continuing loss of blood leads to shock with increased pulse rate and reduced blood pressure.
Significant bleeding within the bowel can be caused by burst blood vessels in diverticulitis or more serious conditions such as bowel cancers. Blood-stained diarrhoea can be caused by chronic inflammatory bowel diseases like ulcerative colitis or Crohn’s disease – these can often be treated by medication and are not incompatible with life at sea but ENG1 candidates need supporting documentation from their specialist.
Cancers will only cause heavy bleeding if they erode into a blood vessel. More commonly they ooze blood into the bowel and smear blood and mucous onto faeces. This is a worrying symptom and needs to be investigated.
Bowel investigations are becoming increasingly powerful with endoscopic visualisation of the gullet, stomach and upper small bowel via the mouth, and large bowel visualisation via the anus. Coupled with CT scans and other tests it is increasingly possible to establish a likely diagnosis and possibly avoid surgical intervention.
A relatively small amount of red rectal bleeding can be alarming especially when splashed into the toilet and mixed with water but the cause is almost certainly haemorrhoids (piles) which is not normally a serious condition. Haemorrhoids are swollen veins which can emerge in the anal area and are associated with repeated back pressure on the anal circulation as, for example, with chronic constipation, heavy lifting, or pregnancy. They can be uncomfortable and can bleed especially when opening the bowels. Treatment is normally simple and consists of numbing the pile with lubricant anaesthetic then trying to ease it back into the back passage where it should be more comfortable.
Another common cause of bright red anal bleeding is an anal fissure or crack which can be caused by passing a large stool when constipated. It is painful and can affect any age group but can be easily treated with a steroid cream and laxatives.
This short summary covers some of the simple everyday causes of blood in the guts but there a few occasions when the cause may be more serious and the amount of bleeding may be substantial. Situations like this are covered in MCA medical courses and it is clearly important to have some people on board who have trained up to that level in order to decide between minor and major conditions and to have some idea what to do.
Dr Ken Prudhoe, MCA Approved Doctor, can be contacted at Club de Mar Medical Centre, Palma de Mallorca.