Functioning of urinary system
Download as PPT, PDF2 likes730 views
The document describes the anatomy and physiology of the urinary system. It discusses the kidneys, which filter blood to produce urine and regulate electrolytes and acid-base balance. Urine travels from the kidneys through ureters to the bladder, where it is stored until voiding through the urethra. The kidneys contain nephrons that filter blood and reabsorb necessary substances. The document also reviews urinary system diseases, diagnostic workup, bladder function, nerve supply, the process of urination, and common urinary problems.
Functioning of urinary system
- 1. Functioning of urinary system Urinary system consists of Kidneys, Ureters, Bladder, Urethra
- 2. Kidney- anatomy Bean shaped organ in retroperitoneum At vertebral level- T12-L3 R- slightly lower; L- slightly larger Functional structure- NEPHRON, spans cortex & medulla, ends in papilla (tip of renal pyramid) Empties into ureter Blood supply- renal artery, branch of Aorta Nerve supply- Sympathetic- causes vasoconstriction Sensory- T10-T11 flank pain
- 3. Kidney- function Excretion of waste- urea & ammonia Reabsorption of water, glucose, amino acids Regulation of electrolytes Maintain acid-base balance Regulation of blood pressure Hormone production Calcitriol- calcium absorption, phosphate excretion Renin- maintain blood pressure Erythropoietin- stimulates erythropoiesis
- 4. Kidney- physiology Nephron- functional unit of kidneys, includes glomerulus & tubule Basic functions- Filtration- of blood in glomerulus Reabsorption- in tubule Secretion- in tubule Net result- excretion
- 5. Kidney- homeostasis Proximal tubule- reabsorption of glucose, amino acids, urea, Na, Cl, K, HCO3, Ca, Mg Loop of henle- Reabsorption of water in descending limb Reabsorption of Na, Cl, K, HCO3, Ca, Mg in ascending limb Distal tubule- reabsorption of NaCl, Mg Collecting duct- secretion of H, K; Na reabsorption (aldosterone); water reabsorption (AVP)
- 7. Kidney- diseases Congenital ADPKD Horseshoe kidney, renal agenesis Acquired Diabetic nephropathy, Glomerulonephritis Nephrotic syndrome Interstitial nephritis, Tubular necrosis Nephrolithiasis, Hydronephrosis, Pyelonephritis Tumors- RCC, Wilm’s tumor
- 8. Work-up History Examination CBC BUN, Cr Calcium, phosphate, alk. phosphatase Urine analysis, 24-hr. urine analysis US KUB
- 9. Urinary bladder Organ controlling urination
- 10. Nerve supply of bladder Detrusor- sympathetic- T11-L2 Storage of urine Sensory afferent- pelvic n.- S2-4 Bladder full Detrusor- parasympathetic- S2-4 Voiding External sphincter- pudendal n.- S2-4 Voluntary control
- 11. Urination Micturition is a spinal reflex Facilitated & inhibited by pontine micturition center through reticulospinal tract in spinal cord Subject to voluntary facilitation & inhibition
- 12. Phases of micturition Storage phase- bladder stores urine Sympathetic stimulation contracts internal sphincter & relaxes detrusor muscle Voiding phase- bladder empties Bladder afferent signals reach pontine micturition center that fires, Parasympathetic stimulation relaxes internal sphincter & contracts detrusor External sphincter is under voluntary control
- 13. Problems of urination Incontinence- stress, urge, mixed Retention Overactive bladder Interstitial cystitis BPH UTI