Urinary Elimination
1) Kidneys – The left kidney is higher than the right kidney due to the position of the liver. Filters waste products of metabolism that collect in the blood. They remove waste from the blood to form urine. The kidneys maintain balance between retention and excretion of fluids ( play key role in fluid and electrolyte balance). The normal adult urine output is 1200 to 1500 ml/ day. An output less than 30 ml/hr indicates possible circulatory, blood volume or renal alterations. Erythropoietin functions within the bone marrow to stimulate RBC production and maturation. Patients with chronic kidney conditions cannot produce sufficient quantities of this hormone are prone to anemia. The kidneys affect calcium and phosphate regulation by producing a substance that converts vitamin D. Patients with chronic alteration in the kidney fuction do not make sufficient amounts of the active vitamin D. They are prone to develop renal bone disease resulting from impaired calcium absorption. Renal hormones affect blood pressure regulation, renal ischemia (decreased blood supply), and renin is released from juxtaglomerular cells. Renin functions as an enzyme to convert angiotensinogen (a substance synthesized by the liver) into angiotension1. Angiotensin 1 is converted to angiotensin 2 in the lungs. Angiotensin 2 causes vasoconstriction and stimulates aldosterone released from the adrenal cortex. Aldosterone causes retention of water, which increases blood volume. The kidneys also produce prostaglandin E2 and prostacyclin, which help maintain renal blood flow through vasodilation. These mechanisms increase arterial blood pressure and renal blood flow.
2) Ureters – The ureters are a tubular structure that enters the urinary bladder. They transport urine from the kidneys to the bladder. Urine draining from the ureters to the bladder is usually sterile.
3) Bladder – The urinary bladder is a hollow, distensible, muscular organ ( detrusor