خدا بنام

به نام خدا

Extracorporeal Shock-wave lithotripsy

(ESWL)

Epidemiology

Nephrolithiasis with a lifetime prevalence13% in men and 7% in women

80-85% Ca- based 20%uric acid,struvite,cystine,……

Pathophysiology

For uric acid,struvite,cystine stones are predictable

For calcium stone formation is multifactorial: hypercalciuria hyperoxaluria hyperuricosuria hypocitraturia dietary factors

Therapeutic option

ESWLUreteroscopyPCNLOpen surgerySWL has been the most commonly used approach49-54% of procedures to treat renal stones

contraindications

Active UTIDistal obstructionPregnancycoagulopathy

Preoperative preparationD/C of anticoagulantsDocumentation of a negative U/CR/O of pregnancyBowel prepAntibiotic CBCRenal function test

Not suitable for ESWLLower pole stonesMorbid obesHounsfield unite>1000SSD>10 cmCystine and brushite are the most resistant to SWLSmall diameter of lower pole infundibulaLower pole with multiple infundibulathe angle formed between the lower infundibulum and the renal pelvis

Position for SWLSupineProne transplant kidney ectopic kidney lower ureter stones

Anesthesia Prevent patient’s movement

Post opAntibioticAnalgesicKUB+SONO2-4 wk after the procedureIn several trrials the use of potassium citrate or tamsulosin with or without methylprednisolone has resulted in superior stone- free rates as compared with placeboFor PT with stones that failed to fragment repeat SWL may be considered 2 weeks or more

Stone free rate

Passage of fragmens may continue for up to 3 months

Adverse effectsObstruction steinstrasse(stone street)6-20%Hematoma risk factors: older age HTN DM IHD obesity

Acute Extrarenal DamageTrauma to organs such as the liver and skeletal muscle, as evidenced by elevated levels of bilirubin, lactate dehydrogenase, serum aspartate transaminase, and creatine phosphokinase within 24 hours of treatment

Parameters begin to fall within 3 to 7 days of SWL treatment and

Are normal at 3 months.

Acute Extrarenal DamagePerforation of the colon Hepatic hematomaSplenic rupturePancreatitisAbdominal wall abscess

Acute Renal Injury

HematuriaHematoma Shockwaves rupture blood vessels and can damage surrounding renal tubules

Chronic Renal InjuryIt is well accepted that shockwaves damage blood vessels, and the resulting hemorrhage initiates an inflammatory response that ultimately leads to scar formation.

Rise in systemic blood pressureDecrease in renal functionIncrease in the rate of stone recurrence

Factors That Induce the Degree of Renal Trauma Associated with Shockwave Lithotripsy

Number of shocksAccelerating voltageKidney size—juvenile vs. adultPreexisting renal impairmentTreatment at a slow rate of shockwave delivery (60 shocks/min or less)