Mechanisms of myocardial depression after bolus injection of sodium bicarbonate.

Purpose: The classic model for the effects of NaHCO3 on myocardial function predicts transient myocardial depression after an intravenous bolus of sodium bicarbonate in association with myocardial acidosis.

Methods: Five anesthetized, paralyzed, and ventilated dogs underwent midline sternotomy. Myocardial global function was assessed by cardiac output, left ventricular (LV) dp/dt, LV end-systolic, and LV end-diastolic pressures.

Transmembrane oxalate exchange: its relationship to idiopathic calcium oxalate nephrolithiasis.

Red blood cell oxalate flux rates were measured in various populations of stone patients and controls. Idiopathic and normocalciuric stone patients and post-prostatectomy patients exhibited rates significantly greater than the nonstone controls. The fact that this abnormality was not limited to patients with calcium oxalate nephrolithiasis suggests that this cellular defect is not universal nor an important etiological factor for calcium oxalate nephrolithiasis.

Hypocalcemia and hypercalcitoninemia in critically ill children.

To study Ca metabolism in critically ill children, we measured ionized Ca (Ca2+), parathyroid hormone (PTH), calcitonin, 25 hydroxycholecalciferol (25[OH] D3), 1-25 dihydroxycholecalciferol (1-25[OH]2D3, and gastrin levels in critically ill children and in healthy controls. Patients were considered hypocalcemic if Ca2+ was less than 1.1 mmol/L.

Absence of persisting parenchymal damage after extracorporeal shock wave lithotripsy as judged by excretion of renal tubular enzymes.

Four renal tubular enzymes, N-acetyl-beta-glucosaminidase, beta-galactosidase, angiotensin-converting enzyme and gamma-glutamyltransferase, were measured in the urine before, and 24 hours and 1 week after extracorporeal shock wave lithotripsy in 20 consecutive patients. Extracorporeal shock wave lithotripsy was performed on the Sonolith 2000 device with the patient under intravenous narcotic sedation with fentanyl. Enzymatic activity per gram of urinary creatinine was consistently but not significantly higher before extracorporeal shock wave lithotripsy than in control subjects.

Impact of percutaneous renal stone removal on renal function: assessment by urinary lysozyme activity.

Lysozyme in the urine in concentrations greater than 3 micrograms per milligram of creatinine reflects renal tubular disease or dysfunction in patients without bowel disease or leukemia. We therefore used urine lysozyme assays to assess renal response to percutaneous nephrostomy and stone removal in 42 patients. Eight patients had striking increases (4.