**2.2 Clinical presentation**

Signs, symptoms and degree of obstructive nephropathy depended on the following factors:


The presenting symptoms of bilateral and chronic obstruction can be nonspecific such as increases in abdominal girth, ankle edema, malaise, anorexia, headache, weight gain, fatigue and shortness of breath.

#### **2.3 Radiographic assessment**

### **2.3.1 Ultrasound**

Ultrasound is the most valuable tool of radiologic assessment of obstructive uropathy in patients with azotemia, even in pregnant and pediatric patients. This investigation provides information about both renal parenchyma and the collecting system. Hydronephrosis is demonstrated as a dilated collecting system separating the normally echogenic renal sinus. Echoes within the collecting system may indicate pyonephrosis, hemorrhage or a lesion of the transitional mucosa. The thickness of the renal parenchyma can be represented the duration of obstruction.

Ultrasonography for diagnosing obstruction can provide false positive (overdiagnosis) and false negative (missing an obstruction) results. The conditions that can cause false negatives with ultrasonography are acute onset of obstruction, an intrarenal collecting system,

Modern Surgical Treatments of Urinary Tract Obstruction 267

The evaluation of choice to detect urolithiasis and intraabdominal anatomy in patients with emergent or complex medical conditions is a computer tomography (CT scan) of the whole abdomen. Pre-nephrostomy placement with CT scan is recommended in selected patients with splenomegaly, colonic malposition and marked colonic distention. (LeRoy., 1996)

Patients who have urinary tract infection are treated with bacteriologically specific antibiotics and these patients need parenteral antibiotics for 36 to 48 hours before surgery to ensure adequate serum levels of effective antibiotics. The recommended regimen is ciprofloxacin 400 mg IV every 12 hr, ampicillin 1 gm IV every 6 hr with gentamicin 1 mg/kg

Laboratory testing of any bleeding problem such as PT, PTT (Prothrombin time, Partial thromboplastin time) and platelet count should be done with appropriate adjustments especially in patients with a history of prolonged bleeding, liver disease, clinically easy brusisability or other conditions predisposing to a coagulopathy. A platelet count should be above 80,000 cells per ml prior to the procedure. Aspirin therapy should be discontinued 1 week prior to the procedure. Caumadin as an anticoagulants must be discontinued. Subcutaneous heparin can be administered for high risk patients with venous thrombosis.

Nephrostomy tube placement can be preferred in both prone and supine positions with highly successful outcome. Most patients usually undergo the procedure in the prone position with abdominal support. Supine position is selected for patients with high surgical risks such as seriously ill patients, patients with endotracheal tubes with or without ventilation, patients with congestive heart failure, patients with complicated fractures and

The advantages of prone or prone oblique with body side of targeted kidney slightly elevated are operator's hands are outside the vertical x-ray beam. (Fig. 5) With supine position with the body side of targeted kidney elevated slightly off the tabletop, the renal

Most patients need only local anesthesia, but some may need intravenous sedation or general anesthesia, the latter specifically for pediatric patients. The type of anesthesia administered depends on the individual patient and indication of nephrostomy tube placement. Simple percutaneous external drainage can be tolerated with local anesthesia or intravenous analgesia with sedation. General anesthesia is preferable in children with all

The imaging guidance equipment is very important in renal access. The guidance system for urinary tract interventions are fluoroscopic guidance, real-time ultrasonography and CT scan.

The puncture of the desired calix can be done in dilated systems. If only the renal pelvic can be identified, initial puncture can be done at renal pelvic following with antegrade

every 8 hr or third generation cephalosporin.

patients who have undergone a major surgical procedure.

access can be performed with ultrasound or CT guidance.

indications of nephrostomy tube placement.

**3.2.2 Patient's position** 

**3.2.3 Anesthetic** 

**3.2.4 Imaging guidance** 

**3.2.4.1 Ultrasound guidance** 

dehydration, and the misinterpretation of caliectasis for renal cortical cyst. (LeRoy., 1996) . False positive imaging for the obstruction can be caused by parapelvic cyst, intrarenal pelvis, high urine flow state and vesicoureteral reflux. (Stables et al., 1978)
