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F C Whittier

Publications and source records attributed to F C Whittier.

60 records · Page 4Linked to original sources
PubMed1973

Fluid secretion in isolated proximal straight renal tubules. Effect of human uremic serum.

We have examined the effect of normal and uremic human sera on the transtubular flow of fluid in isolated perfused segments of rabbit proximal convoluted and straight renal tubules. Proximal convoluted and straight tubules absorbed fluid from the lumen when the external bath was normal rabbit serum. Normal human sera in the bath depressed net fluid absorption in both tubular segments, but more importantly, uremic human serum caused proximal straight tubules to secrete fluid into the lumen. Fluid secretion was also demonstrated indirectly by observing in nonperfused proximal straight, but not proximal convoluted tubules, that the normally collapsed lumens opened widely in uremic serum. Nonperfused proximal straight tubules developed expanded lumens even after a 25-fold dilution of human uremic serum with normal rabbit serum, whereas lumen expansion occurred only in undiluted normal human serum, on the average. Serum from acutely uremic rabbits possessed secretory activity but normal rabbit serum did not. The secretory effect of uremic sera in proximal straight tubules was inhibited by cooling and ouabain and probenecid. The secretory activity of uremic sera was removed by dialysis, but not by freezing or boiling. Para-aminohippurate and benzoate caused fluid secretion in proximal straight tubules but urea, creatinine, guanidinosuccinate, and urate did not. On the basis of these results, we suggest that the secretory factor in serum may be a substance or group of substances possibly related to the hippurate class of organic molecules that are accumulated to relatively high concentrations in renal failure. The secretory material in the serum of uremic patients may significantly influence the transport of salt and water in relatively intact residual nephrons.

Acetates↗
PubMedDate not supplied

Dialysis leg cramps. Efficacy of quinine versus vitamin E.

A controlled randomized double-blind study was done to determine the frequency and severity of leg cramps in 40 patients on dialysis with a history of leg cramps. All patients entered a 2 month placebo washout and were randomized into a 2 month double-dummy phase of quinine 325 mg at bedtime versus vitamin E 400 IU at bedtime. Of the 29 patients completing the study, 16 received quinine and 13 vitamin E. During placebo washout, the vitamin E group had a mean of 10.4 leg cramps per month, and the quinine group had a mean of 10.9. The vitamin E and quinine groups had a 1 month reduction in leg cramps to 3.3 and 3.6, respectively (p < 0.0005 for both groups combined); this was sustained at 2 months. A severity of pain index showed a statistically significant decrease for both groups. The 95% confidence interval for the difference between the number of leg cramps after vitamin E versus quinine treatment (95% confidence interval, -3.8, +3.2) suggests similar efficacy. Quinine and vitamin E were effective treatments for leg cramps in these patients. Considering the potential toxicity of quinine, vitamin E is recommended as the initial treatment of choice for patients on dialysis with leg cramps.

Adult↗
PubMedDate not supplied

End of life issues in ESRD. A study of three decision variables that affect patient attitudes.

The substantial end-stage renal disease (ESRD) mortality rate reflects an older population, worsening comorbidity, and increased cardiovascular disease. Advance directives in ESRD may simplify issues such as cardiopulmonary resuscitation (CPR) and dialysis discontinuation. However, ESRD patients with advance directives may change their mind or allow surrogate leeway for override of end-of-life decisions. Three decision variables (requesting CPR, discontinuation of dialysis with depression, or discontinuation with dementia) were studied in 141 ESRD patients through a 47 item questionnaire. Duration of dialysis (> or = 4 years) (P = 0.002) and prior CPR experience (P = 0.02) increased the probability of refusing CPR by 12 times. The use of surrogates and substituted judgement for dialysis discontinuation with depression was more likely in women (P = 0.0006) and in patients with higher levels of education (P = 0.003). The odds of deciding to discontinue given dementia were three times greater for hemodialysis than peritoneal dialysis patients (P = 0.03). Eighty-three percent of the patients requested that physicians periodically check with them to determine if their advance directives had changed. The authors conclude that advance directives may assist ESRD patients, families, and staff with end-of-life decisions. Three end-of-life decision variables are significantly affected by duration and type of dialysis, previous CPR, gender, and level of education.

Adult↗
PubMedDate not supplied

An approach to clinical acid-base problem solving.

This article demonstrated a systematic approach to acid-base problem solving through the application of the so-called "Rules of Five." This technique was compared with other options for acid-base problem solving, namely, clinicians' use of gestalt or an acid-base map. The superiority of the systematic approach in uncovering triple acid-base disorders was shown.

Acid-Base Imbalance↗