GU Overview WK2 Flashcards
Stages Kidney Development
- Pronephros
- Mesonephros
- Metanephros
- 5-9wk ascend from pelvis to abdomen
- True kidney
- 9-10wk begins functioning
Nephrogenesis: Period of Development
- 8-36wk
Nephrogenesis: Period Critical Development
- 31-36wk
Number of nephrons FT at birth
- 800,000-1.2mil nephrons
Bladder Development
- 4-6wk begins formation
Urethra Development
- 12-13wk
GFR: Definition
- filtrate/min formed in glomerulus
GFR: Rate in utero
low
GFR: Increase RT
- Initial increase rt increase glomerular perfusion pressure
- Later increase rt increase renal blood flow
GFR RT (3)
- BP peritubular capillaries*
- Hydrostatic pressure glomerular capillaries and bowman’s capsule
- Colloid osmotic pressure capillaries
GFR Levels
- <34wk
- FT birth
- FT 2wk
- 2yr
<34wk
Tubular system function RT
- Renal blood flow
- GFR
Proximal Tubules: Reabsorb
- H2O
- Na
- K
- Glucose
- AA
- Bicarbonate
- Phos
- Mag
- Cl
- Ca
Proximal tubules: Secrete
- H+
- Organic acids
Distal convoluted tubules: Secrete
- K
- H+
Distal convoluted tubules: Reabsorb
- H2O (w ADH)
- Na (w aldosterone)
Loop of Henle and collecting ducts: Function
- Concentrate vs dilute urine
FT vs adult kidney
- Decrease ability concentrate urine
- Decrease ability respond to fluid load
- Altered tubular function
PT vs FT kidney
- Decrease GFR
- Decrease response renal tubules to aldosterone
RAAS: Function
- Increase NaCl and H2O reabsorption peritubular capillaries →
- Increase intravascular volume
- Increase CO
- Increase BP
RAAS cycle
- Renin
- Convert angiotensinogen (liver) → angiotensin
- Angiotensin
- ACE (lungs, renal endothelium) converts angiotensin → angiotensin II
- Angiotensin II
- Aldosterone
Renin released RT
- Decrease renal blood flow
Angiotensin II: Function
- Vasoconstrictor
- Peripheral blood vessels
- Efferent arteriole
- Increase reabsorption
- Na
- Cl
- H2O
- Release aldosterone
Aldosterone Release RT
- Angiotensin II
- Adrenocorticotropic hormone
- hyperK
Aldosterone Function
- Increases reabsorption
- Na
- CL
- H2O
- Increase intravascular volume
ADH: Release RT
- Decrease intravascular volume
- Increase plasma osmolality
- Increase angiotensin II
ADH: Function
- Increase permeability collecting ducts
- Increase H2O reabsorption
- Increase intravascular volume
RAAS: Inhibitors
- ANP
- BNP
ANP and BNP: Function
- Decrease renin, angiotensin, angiotensin II, aldosterone
- Peripheral vasodilation
- Decrease BP
- Decrease intravascular volume
- Increase diuresis
Kidney: Function
- Regulate BP
- Systemic
- Renal blood flow
- Remove metabolic waste
- Fluid volume and electrolytes balance
- Acid base homeostasis
- Erythropoietin
- Vitamin D metabolism
AKI: Incidence
- 8-24%
AKI: Risk Factors
- VLBW
- Low 5min apgar
- Maternal meds (esp abx, NSAIDs)
- Intubation birth
- RDS
- PDA
- Phototx
- Neonatal meds (abx, NSAIDs, diuretics)
- Congenital diaphragmatic hernia
- ECMO
AKI: s/s
- Oliguria
- Systemic hypotension
- Dehydration or volume overload
- Decrease activity
AKI: Long Term Complications
- Progressive renal disease
- CKD
- HTN
- Renal tubular acidosis w impaired renal tubular growth
AKI: Types
- Prerenal
- Intrinsic
- Postrenal
Prerenal AKI: Etiology
- Hypotension/hypoperfusion (most common)
- Congestive heart failure
- Respiratory distress/hypoxia
- Dehydration
- Hypoalbuminemia
- Nephrotoxic meds
Hypotension/hypoperfusion RT
- Neonatal asphyxia
- Ischemic damage
- Blood loss
- 3rd space loss
- Dehydration
- Shock
Prerenal AKI: Dx
- fluid challange
- NS 10-20ml/kg/30min
- determine intravascular fluid loss
Intrarenal: Etiology
- Prolonged prerenal injury
- Ischemic injury
- Obstructive renal injury
- Congenital abnormalities
- Congenital inflammation/infection
- Nephrotoxic meds
- Aortic thrombosis
- Artery thrombosis
- Acute tubular nephrosis