Blood Vessels: IV Pelvis & Lower Limb (PDF)

Blood Vessels IV – Pelvis and Lower Limb; Anastomoses; Development Course Learning Objective Cardiovascular: Recall the structures that allow for the exchange of gases and nutrients throughout the body by tracing blood flow and identifying related structures...

Blood Vessels IV – Pelvis and Lower Limb; Anastomoses; Development Course Learning Objective Cardiovascular: Recall the structures that allow for the exchange of gases and nutrients throughout the body by tracing blood flow and identifying related structures in the cardiovascular system.  Lecture Learning Objectives 1. Visually identify the arteries 4. Describe the flow of fetal and veins of the pelvic cavity, circulation noting what they supply or 5. Explain how fetal and neonate drain circulation varies, specifically 2. Recall major vascular addressing the role of the anastomoses, the vessels foramen ovale, ductus involved, and describe their arteriosus, ductus venosus, clinical importance. and umbilical vessels 3. Diagram the development of the aortic arches, linking the adult derivatives of each arch Pelvic Cavity Vessels  Suprarenal LO 1 gland Blood Vessels in the Pelvis Kidney Aorta and IVC divide into IVC 1. Common iliac Internal iliac External iliac Aorta External iliac exit pelvis though the Common inguinal canal, created by the inguinal iliac ligament and surrounding structures, to become the femoral a/v Internal iliac External iliac Urinary bladder  LO 1 Blood Vessels of the Pelvis Common iliac Internal iliac a/v Internal 1. Anterior trunk iliac Contribute to pelvic organs, perineum, gluteal region, thigh, Posterior and fetus/placenta trunk 2. Posterior trunk Anterior trunk External Lower posterior abdominal wall, iliac posterior pelvic wall, and gluteal region Posterior Anterior Lateral view of pelvic cavity  LO 1 Abdominal aorta Inferior vena Common cava iliac aa. Internal iliac a. Common iliac vv. External iliac a. External iliac v. Vessels of the Lower Limb  LO 1 Blood Vessels of the Lower Limb External iliac Profunda femoris/deep femoral Circumflex and perforating Femoral Popliteal Posterior tibial Fibular Anterior tibial Paired veins with shared name Unpaired superficial v.  Arteries of the Hip LO 1 Femoral a. and Thigh External iliac a. Femoral circumflex aa. Femoral a. Profunda femoris a. (deep femoral) Profunda femoris Femoral a. Perforating aa.  LO 1 External iliac External iliac a. a. Femoral a. Femoral a. Profunda femoris Lateral Lateral Medial Medial  LO 1 Arteries of the Femoral Knee and Leg Popliteal Femoral Popliteal Posterior tibial a. Fibular a. Anterior tibial a. Anterio Posterior leg r leg M L M L  Superficial Veins LO 1 of the Lower Limb Small Great saphenous saphenous v. v. - drains – drains into into femoral v. popliteal v. Dorsal venous arch Vascular Anastomoses  LO 2 Coronary Anastomoses Right and Left Coronary Arteries: Between the branches of the anterior interventricular and posterior interventricular aa. on inferior aspect of the heart. Between the RCA and the left circumflex artery in the coronary sulcus. Between the septal branches of both RCA and LCA in the interventricular septum. Clinical Importance: These provide limited collateral circulation in coronary artery disease or a myocardial infarction. Drake et al. (2018), Gray’s Basic Anatomy  LO 2 Cerebral Anastomoses (Circle of Willis) Vessels: Anterior communicating a., anterior cerebral aa., posterior communicating aa., and posterior cerebral aa.. Clinical Importance: Critical in maintaining blood supply to the brain during occlusions or strokes. Drake et al. (2018), Gray’s Basic Anatomy  LO 2 Azygos System Anastomosis Vessels: azygos v., hemiazygos v., accessory hemiazygos v. Clinical importance: Capable of returning venous blood from the lower part of the body to the heart if the inferior vena cava is blocked. Azygos Vein is a photograph by Science Photo Library which was uploaded on September 16th, 2018.  LO 2 Abdominal Anastomoses Celiac Trunk SMA Pancreaticoduodenal arteries communicate with the celiac axis and the SMA and supply the pancreas and duodenum Clinical Importance: Ensure continued perfusion to the foregut during vascular blockages.  Abdominal Anastomoses SMA IMA Anastomoses at the marginal artery of Drummond and the arc of Riolan. Clinical Importance: Ensure continued perfusion to the intestines during vascular blockages. Common site for thromboses. Mann, M. R., Kawzowicz, M., Komosa, A. J., Sherer, Y. M., Łazarz, D. P., Loukas, M.,... & Pasternak, A. (2021). The marginal artery of Drummond revisited: A systematic review. Translational Research in Anatomy, 24, 100118.  LO 2 Upper Limb Suprascapular a. Dorsal scapular a. Anastomoses Shoulder: Anastomoses between Circumflex suprascapular a. scapular from subscapular a. (via subscapular a. Suprascapular a. circumflex scapular a.) suprascapular a. dorsal scapular Dorsal scapular a. Anterior posterior humeral circumflex aa. Circumflex Clinical Importance: scapular from Essential in maintaining blood subscapular a. supply during traumatic vascular injuries or limb ischemia  LO 2 Lower Limb Anastomoses Superior medial Superior lateral geniculate a. Knee Region: Genicular geniculate a. anastomoses involving the Patellar femoral, popliteal, and anastomosis geniculate aa. Inferior lateral Inferior geniculate a. medial Clinical Importance: geniculate Essential in maintaining blood a. supply during traumatic vascular injuries or limb ischemia.  LO 2 Internal Iliac and External Iliac Arteries Vessels: External iliac a./v. deep circumflex iliac a./v. iliolumbar a./v. internal iliac a./v. Clinical importance: Important in cases of occlusion or surgical ligation.  Hepatic Portal System/ LO 2 2 1 Portacaval Anastomoses Portosystemic Anastomoses: Connections between the portal and systemic venous systems: 4 1. Left gastric v. Esophageal vv. azygos v. 2. Right hepatic v. Paraumbilical vv. superficial epigastric v. 3. Superior rectal v. middle and inferior vv. internal iliac vv. 4 4 4. Superior and inferior mesenteric, splenic vv. various retroperitoneal vv., superficial epigastric v., inferior vena cava Clinical Importance: Can lead to varices 3 (esophageal, rectal) in cases of portal hypertension. Cardiovascular Embryology  LO 3 Pharyngeal Arch Arteries  LO 3 Aortic Arches  Arch Derivative LO 3 Aortic Arches I Mostly obliterates II Mostly obliterates III L and R common carotids; proximal portion of internal carotids; external carotid forms as outgrowths IV Left: Aortic arch/descending aorta; Left subclavian forms as outgrowth: 7th intersegmental a. R: Right subclavian; brachiocephalic trunk forms from ventral aorta connecting right subclavian and common carotid V Does not exist in humans VI Left: Portion of left pulmonary arteries, ligamentum arteriosum; pulmonary trunk forms from portion of aortic sac Right: Portion of right pulmonary arteries  LO 4 and 5 Fetal and Neonatal Circulation Fetal circulation is designed to serve prenatal needs: Fetal lungs do not provide gas exchange and pulmonary vessels are vasoconstricted System modifies at birth to establish neonatal pattern Establishes healthy respiration Helpful video! Fetal circulation  LO 4 and 5 Fetal and Neonatal Circulation 1. Umbilical veins c a. Carry high-oxygen blood from placenta to fetus b b. ½ flows through liver’s hepatic veins; ½ to ductus venosus a 1 c. Blood from hepatic vein mixes with low-oxygen blood from IVC (fetal systemic circulation) Fetal circulation Why are the veins red in the image?  LO 4 and 5 Fetal and Neonatal Circulation 2. Right atrium a. Receives blood from IVC/hepatic a veins (moderate oxygen) and SVC b (low oxygen) c b. Most blood skips pulmonary system; flows from a Right atrium→ foramen ovale→ left atria → left ventricle → aorta c. Some blood goes to right ventricle→ pulmonary trunk→ to 1. Lungs and returns to left atria via pulmonary veins Very little blood goes this route because lungs are “squeezed” (closed alveoli) and pulmonary vascular resistance is high; blood travels path of least resistance 2. Aorta via ductus arteriosus Fetal circulation  LO 4 and 5 Fetal and Neonatal Circulation 3. Blood in aorta enters fetal systemic system where it a. Will supply fetus and return to heart via vena cavae a b. Is sent to placenta via umbilical arteries to receive oxygen b Fetal circulation  LO 5 Fetal and Neonatal Circulation At birth ductus venosus, foramen ovale, ductus arteriosus, and umbilical vessels are no longer needed Ductus venosus- connection between umbilical vein and IVC closed by muscular sphincter; becomes ligamentum venosum Foramen ovale - valve between atria closes First breath causes lungs to expand, decreasing pulmonary vascular resistance and decreasing pressure in right side of heart Low pressure in right atrium, high pressure in left atrium causes valve to close Neonatal circulation Full closure occurs due to tissue proliferation over months  LO 5 Fetal and Neonatal Circulation Ductus arteriosus- closes completely a few days after birth due to variation in blood pressure between systemic (+) and pulmonary (-) circulation Becomes ligamentum arteriosum Umbilical vessels- placental circulation occludes when umbilical cord is tied, internal vessels remain and form ligaments Umbilical vein= ligamentum teres Neonatal circulation Umbilical arteries= medial umbilical ligament  LO 5 Fetal and Neonatal Circulation Ductus arteriosus- closes completely a few days after birth due to variation in blood pressure between systemic (+) and pulmonary (-) circulation Becomes ligamentum arteriosum Umbilical vessels- placental circulation occludes when umbilical cord is tied, internal vessels remain and form ligaments Umbilical vein= ligamentum teres Neonatal circulation Umbilical arteries= medial umbilical ligament