[Perioperative Blood Pressure Changes in a Patient Undergoing One-stage Bilateral Nephrectomy for Treatment-resistant Hypertension].

We describe our experience with a 15-year-old girl receiving anesthesia during one-stage bilateral nephrectomy for treatment-resistant hypertension due to chronic renal failure. Approximately 10 minutes after removal of both kidneys, a reduction in blood pressure associated with decreased cardiac contractile force was observed and this necessitated catecholamine administration. However, blood pressure was sufficiently improved approximately 60 minutes later, and catecholamine administration was not necessary after she awoke from anesthesia. Although administration of an antihypertensive agent as required after surgery, as had been the case before surgery, the dose was gradually tapered and we were able to stop drug administration on postoperative day 31.

Assessment of kidney function in children by enzymatic determination of 2- or 24-h creatinine clearance: comparison with inulin clearance.

BACKGROUND: Although renal inulin clearance (Cin) is the gold standard for evaluation of kidney function, it cannot be measured easily. Therefore, creatinine clearance (Ccr) is often used clinically to evaluate kidney function. Enzymatically measured Ccr was recently found to be much higher than Cin because of the tubular secretion of creatinine (Cr). This study compared three measures of renal clearance, inulin, 2-h Ccr, and 24-h Ccr, in children. METHODS: Kidney function was evaluated in 76 children (51 males and 25 females) aged 1 month to 18 years with chronic kidney disease (CKD) by three renal clearance methods at almost the same time. RESULTS: Correlations between each pair of three renal clearance measurements were determined. Approximate glomerular filtration rate (GFR) was equal to 62 % of 2-h Ccr or 76 % of 24-h Ccr. CONCLUSION: Cr secretion by renal tubules was approximately 50 % of the GFR. In this study, we indicate that the measurements of 2-h Ccr or 24-h Ccr do not show true GFR but we could infer approximate GFR from the values. The use of 2- or 24-h Ccr might contribute to the treatment of pediatric CKD patients.

Measurements of serum cystatin C concentrations underestimate renal dysfunction in pediatric patients with chronic kidney disease.

BACKGROUND: In our clinical experience, cystatin C (CysC) concentrations are not as high as expected in patients with chronic kidney disease (CKD) and high-stage renal dysfunction. We therefore investigated whether measurements of serum CysC result in an underestimation of renal dysfunction in pediatric patients with CKD. METHODS: Glomerular filtration rate (GFR) was estimated from serum creatinine (Cr) concentration, using the equation Cr-GFR (%) = [0.30 × body length (m)/serum Cr] × 100; and from serum CysC concentration, using the equation Cys-GFR (%) = (0.70/serum CysC) × 100. We investigated the relationship between GFR estimated by these 2 equations. Patients aged 2-12 years were assorted into 5 groups, based on GFR-Cr categories of <12.5, ≥12.5 to <25, ≥25 to <50, ≥50 to <75, and ≥75%, and GFR-CysC/GFR-Cr ratios were compared in these 5 groups. RESULTS: The median GFR-CysC/GFR-Cr ratio in groups of patients with GFR-Cr of <12.5, ≥12.5 to <25, ≥25 to <50, ≥50 to <75, and ≥75% were 2.28, 1.48, 1.22, 1.18 and 0.98, respectively, with statistically significant differences between any two groups (p < 0.001). CONCLUSION: Measurements of serum CysC concentrations lead to underestimation of renal dysfunction in pediatric patients with CKD.