C. Byrne

Prediction of creatinine clearance from serum creatinine in spinal cord injury patients.

Measured endogenous creatinine clearance (Ccr) was compared with the predicted Ccr in 22 paraplegic, 36 tetraplegie and n ambulatory male individuals as well as 11 ambulatory females all of whom had normal renal function. While the predicted and measured values closely matched in the ambulatory patients the predicted values in the spinal cord injured patients consistently exceeded the measured values. It thus appears that the original Cockcroft and Gault formula;when applied to SCI patients can be misleading. Modification of the original formula using a correction factor of 0.8 in paraplegics and 0.6 in tetraplegics was found to allow prediction of Ccr from age, sex, body weight, and serum creatinine in these patients with reasonable accuracy.

Features of Residual Renal Function in End-Stage Renal Failure Associated with Spinal Cord Injury

The characteristics of end-stage renal disease (ESRD) complicating spinal cord injury (SCI) were studied retrospectively in 43 male hemodialysis patients. A control group of male patients dialyzed in the same institution were studied for comparison. The SCI patients had significantly lower serum creatinine concentrations and daily urinary creatinine excretion than the control group, despite comparable creatinine clearances. Therefore, serum creatinine, when compared with the familiar values in non-SCI patients, may greatly underestimate the severity of the renal impairment. Urine optput was higher, urine specific gravity lower, and renal glucosuria more common in the SCI patients. 24-hour urinary protein excretion was higher and serum albumin was lower in the SCI patients, with 48% of the patients exhibiting nephrotic range proteinuria. Urine pH was markedly elevated, and pyuria and bacteruria were present in all SCI patients. Fractional excretion of potassium (159 ± 16%) exceeded its filtered load in most SCI patients.

Clinicopathological Characteristics of Dialysis Patients with Spinal Cord Injury

Forty-three spinal cord injured patients with endstage renal disease (ESRD) maintained on hemodialysis were studied. The most prevalent renal lesions consisted of chronic pyelonephritis and amyloidosis while the main renal functional features included nephrotic range proteinuria, high urine output and relatively low serum creatinine for the degree of renal insufficiency. Normocytic, normochromic anemia with low reticulocyte response, low serum iron and iron binding capacity and high transfusion requirement and serum ferritin were noted. Various cardiovascular, pulmonary and gastrointestinal abnormalities were found with considerable frequencies. The incidence of amyloidosis was much higher than that reported previously. This is thought to be due to continued progression of amyloidosis occasioned by longer survival in the present series.

Prevention of metabolic alkalosis induced by gastric fluid loss using H2 receptor antagonist

Gastric fluid loss is a common cause of metabolic alkalosis. We studied various acid-base parameters in 20 patients undergoing continuous nasogastric (NG) suctioning for periods ranging from 3 to 17 days. Ten patients received cimetidine 300 mg intravenously every 6 hr (cimetidine-treated group). The remaining 10 patients received an antacid compound through the NG tube (control group). The rise in plasma bicarbonate concentration was significantly greater in the control group as compared to the cimetidine-treated group. As expected, gastric acid output was considerably lower in the cimetidine-treated group than in the control group. We conclude that cimetidine administration may be used in preventing metabolic alkalosis associated with gastric fluid loss by inhibiting gastric secretion of HCl.

Effects of glucose feeding on renal electrolyte and H+ transport

Changes of urinary pH, titratable acidity, ammonium, bicarbonate and PCO2, as well as plasma insulin and various plasma and urine electrolytes were studied in 15 normal individuals during a 5-hr glucose tolerance test. After glucose ingestion, urine pH and bicarbonate excretion rose while urine titratable and total acidity, ammonium, Na, K, Cl, phosphorus and PCO2 fell significantly. Serum bicarbonate rose while serum potassium, phosphorus, and anion gap decreased following oral glucose administration. Glucose feeding and the resultant rise in insulin are, therefore, associated with a considerable reduction in urine acidity and Na, K, Cl, and phosphorus excretion. While a significant fall in urinary Na, K and phosphorus has been shown to occur following glucose and insulin administration, their effect on renal H+ excretion in man has not been investigated previously. The mechanism of the observed fall in urine acidity is not clear and requires further investigation.