Post-Obstructive Diuresis: Physiopathology, Diagnosis and Management after Urological Treatment of Obstructive Renal Failure

Abstract

Obstructive acute renal failure is both a medical and a surgical emergency. The first treatment modality is urological by relief of obstruction. Post-obstructive diuresis is an abnormal condition of prolonged polyuria, involving both excessive solute and water loss, after acute drainage of obstructed urinary tract system. Physiopathology mechanisms are multiples. In most patients, diuresis will resolve once the kidneys normalize the volume and solute status and homeostasis is achieved. Post-obstructive diuresis can occur in up to 50% of patients with substantial urinary tract obstruction and can be life-threatening if it becomes pathologic. It can be detected by hourly monitoring of diuresis. Medical treatment of post-obstructive diuresis consists of oral or intravenous fluids adjusted to the findings of clinical examination, diuresis (volume and electrolytes) and close monitoring of patient. Fluid compensation should be tapered off over several days. Patients at high risk of post-obstructive diuresis should be identified and appropriately monitored.

Acute kidney injury due to bilateral malignant ureteral obstruction: Is there an optimal mode of drainage?

“…Sodium absorption increases in the proximal tubules, but this increase is associated with a more significant decrease in sodium absorption in the juxtaglomerular nephrons. Furthermore, there is a reduction in the medullary ability to concentrate urine to only 350–400 mOsm[ 51 , 55 , 57 ]. This decrease in tonicity results in a drop in water absorption in the descending part of the loop of Henle.…”

“…Decrease in urine output is a common presentation, but it is not specific to Po-AKI[ 41 , 51 ]. Patients with Po-AKI may present with loin tenderness and fever when obstruction is associated with infection[ 51 , 57 ].…”

“…Despite their fundamental roles, these pharmacological and conservative interventions may have a lower effect in the management of Po-AKI than in the management of the other types, relative to the role of drainage[ 51 , 57 ]. Renal replacement therapy is considered in specific circumstances, such as the progression of complications in the severe cases with pulmonary edema, persistent hyperkalemia, and disturbed consciousness.…”

Obstructive Neoplastic Anuria Overview at Ibn Rochd University Hospital–A Retrospective Study

“…After the diversion, the early detection of post-obstructive diuresis is important. It is defined by a diuresis greater than 3000ml /24h [8]. Screening is based on hourly monitoring of diuresis after removal of the obstacle and the blood ionogram.…”

“…Screening is based on hourly monitoring of diuresis after removal of the obstacle and the blood ionogram. [2], it is a complex phenomenon that involves physiological, biochemical, hormonal and immunological mechanisms [8]. Percutaneous nephrostomy is an excellent initial procedure to relieve malignant ureteric obstruction with minimal complications.…”