Paradoxical increase in blood pressure following bilateral native nephrectomy

Shift from severe hypotension to salt-dependent hypertension in a child with autosomal recessive polycystic kidney disease after bilateral nephrectomies: a case report

BACKGROUND

Autosomal recessive polycystic kidney disease (ARPKD) is a significant cause of morbidity and mortality in infants and children. In severe cases bilateral nephrectomies are considered but may be associated with significant neurological complications and life-threatening hypotension.

CASE PRESENTATION

We describe a case of a 17 months old boy with genetically confirmed ARPKD who underwent sequential bilateral nephrectomies at the age of 4 and 10 months. Following the second nephrectomy the boy was started on continuous cycling peritoneal dialysis with blood pressure on the lower range. At the age of 12 months after a few days of poor feeding at home the boy experienced a severe episode of hypotension and coma of Glasgow Come Scale of three. Brain magnetic-resonance imaging (MRI) showed signs of hemorrhage, cytotoxic cerebral edema and diffuse cerebral atrophy. During the subsequent 72 h he developed seizures requiring anti-epileptic drug therapy, gradually regained consciousness but remained significantly hypotensive after discontinuation of vasopressors. Thus, he received high doses of sodium chloride orally and intraperitoneally as well as midodrine hydrochloride. His ultrafiltration (UF) was targeted to keep him in mild-to-moderate fluid overload. After two months of stable condition the patient started to develop hypertension requiring four antihypertensive medications. After optimizing peritoneal dialysis to avoid fluid overload and discontinuation of sodium chloride the antihypertensives were discontinued, but hyponatremia with hypotensive episodes reoccurred. Sodium chloride was reintroduced resulting in recurrent salt-dependent hypertension.

CONCLUSIONS

Our case report illustrates an unusual course of blood pressure changes following bilateral nephrectomies in an infant with ARPKD and the particular importance of tight regulation of sodium chloride supplementation. The case adds to the scarce literature about clinical sequences of bilateral nephrectomies in infants, and as well highlights the challenge of managing blood pressure in these patients. Further research on the mechanisms and management of blood pressure control is clearly needed.

Increased use of antihypertensive medications after partial nephrectomy vs. radical nephrectomy

PURPOSE

A prospective study of partial vs. radical nephrectomy demonstrated worse overall survival in patients undergoing partial nephrectomy which appeared to be driven by cardiovascular outcomes. We sought to determine if the blood pressures or use of antihypertensive medications differed between patients who underwent partial or radical nephrectomy.

MATERIALS AND METHODS

A tertiary-referral institutional renal mass database was queried for patients between 2006 and 2012 undergoing partial or radical nephrectomy. Serial blood pressure follow-up, clinicopathologic variables, and changes in medications were collected. Patients were excluded for inadequate data, noncurative-intent surgery, noncancer surgical indication, and absence of medication information. Time-dependent hemodynamic changes were compared by split-plot analysis of variance and addition to antihypertensive regimen was studied as time-to-event survival analyses with Kaplan-Meier curves and a Cox proportional hazards model.

RESULTS

A final cohort of 264 partial nephrectomy and 130 radical nephrectomy cases were identified. Patients undergoing partial nephrectomy were younger, more likely to have T1 tumors, and had lower preoperative creatinine (P<0.001 for all). No differences were noted on postoperative hemodynamics (P>0.05). Significantly more patients who underwent partial nephrectomy added antihypertensive medications postoperatively (P≤0.001) and surgical treatment remained as a significant independent predictor on Cox regression (hazard ratio = 2.51, P = 0.002). Limitations include the retrospective nature of the study and potential for unidentified confounders.

CONCLUSION

Hemodynamic parameters after radical or partial nephrectomy may be different. The etiology of this observation, is currently unexplored. Additional prospective mechanistic investigations are warranted.