CIRCULATORY SYSTEMBLOOD CIRCULATION TO THORAX AND ABDOMINAL CAVITY : CIRCULATORY SYSTEMBLOOD CIRCULATION TO THORAX AND ABDOMINAL CAVITY Presented by;
M.K Lamba BLOOD SUPPLY TO THORAX : BLOOD SUPPLY TO THORAX The arterial supply is to thorax mainly by descending aorta. In thorax cavity it gives off many paired branches which supply the walls of the thoracic cavity and organs within the cavity, includes the;
Intercostal arteries Slide 3: Bronchial arteries: supply to bronchi and their branches, connective tissue in lungs and lymph nodes of lungs.
Oesophageal arteries: supply to the oeso- phagus.
Intercostal arteries: that runs along the inferior border of the ribs and supply the intercostal muscle, some muscles of thorax, ribs, skin and connective tissues. VENOUS RETURN FROM THORAX : VENOUS RETURN FROM THORAX Most of the venous from thoracic cavity is by Azygos vein and Hemiazygos vein.
The Azygos vein joins superior venacova and Hemiazygos vein joins the left brachiocephalic vein. BLOOD SUPPLY TO ABDOMINAL CAVITY : BLOOD SUPPLY TO ABDOMINAL CAVITY The abdominal cavity supplied by abdominal aorta which begins at the diaphragm, in front of the lower border of the body of the last thoracic vertebra and descending in front of the vertebral column ends on the body of the fourth lumbar vertebra dividing into two iliac arteries. Slide 6: Many branches arise from abdominal aorta which are paired and unpaired;
The paired branches are:
Inferior phrenic arteries: supply to diaphragm.
Renal arteries: supply to kidneys.
Testicular/ Ovarian arteries: supply testes in male and ovaries in female. Slide 7: The Unpaired branches are: coeliac artery and mesenteric artery.
1. The coeliac artery: is about 1.25 cm long. It arise immediately below the diaphragm and divides into three branches;
Left gastric artery: supplies the stomach.
Splenic artery: supplies pancreas and spleen.
Hepatic artery: supply to liver, gall bladder parts of stomach and pancreas. Slide 8: 2. Mesenteric artery: The mesentric artery has two branches;
Superior mesenteric artery: it branch from aorta between the coeliac artery and renal arteries. It supply whole small intestine and half of large intestine.
Inferior mesenteric artery: arise from aorta 4 cm above its division into common iliac arteries. It supplies the distal half of the large intestine and part of rectum. VENOUS RETURN FROM ABDOMINAL CAVITY/ PORTAL CIRCULATION : VENOUS RETURN FROM ABDOMINAL CAVITY/ PORTAL CIRCULATION The inferior venacova is the largest vein in the body which collect de- oxygenated blood from lower portion of body and drain into right atrium. Paired testicular, ovarian, renal and adrenal veins joins the inferior venacova. The blood from the remaining organs in the abdominal cavity passes through the liver called as portal circulation before entering the inferior venacova. In the portal circulation venous blood passes from the capillary beds of the abdominal part of digestive system, spleen, pancreas and liver. It then passes through a second capillary bed, the hepatic sinusoids before entering inferior venacova. Slide 10: Slide 11: Portal vein: The portal circulation formed by the union of several veins;
Splenic vein: drain blood from spleen, pancreas and part of stomach.
Inferior mesenteric vein: return blood from rectum, pelvic and descending colon of large intestine and joins splenic vein.
Superior mesenteric vein: Return blood from small intestine.
Gastric vein: from stomach and esophagus.
Cystic vein: bring blood from gall bladder.