Tolerance of hemodialysis: a randomized prospective trial of high-flux versus conventional high-efficiency hemodialysis.

Hemodialysis is frequently complicated by hypotension and associated symptoms. It has been suggested that these symptoms may be related to the biochemical changes caused by cellulosic dialysis membranes. In this study, a prospective randomized crossover trial was conducted comparing the incidence of hypotension and acute symptoms during dialysis with large-surface-area (1.6 m2) cellulosic (cuprophane [CUP]) and noncellulosic (polyacrylonitrile [PAN], AN69) membranes. Dialyzers were used for a single use only. There was no difference in predialysis BUN, predialysis blood pressure, intradialytic weight gain, blood flow, dialysis efficiency (urea reduction), dialysis duration, hematocrit, or erythropoietin dose between the two study phases. When these clinical characteristics were matched, there was no difference in the number of episodes of hypotension (CUP, 19 +/- 3; PAN, 22 +/- 3; P = not significant [NS]). The incidence of symptomatic hypotension, as reflected by the number of episodes of hypotension requiring more than 100 mL of saline for correction, was also not different between study phases (CUP, 10 +/- 1; AN69, 11 +/- 2; P = NS). The incidence of intradialytic symptoms, including emesis, cramping, headache, angina, pruritus, and bronchospasm, was similar during the two study phases (CUP, 11 +/- 2; AN69, 10 +/- 1; P = NS). It was concluded that noncellulosic membranes do not offer any significant advantage over cellulosic membranes in reducing the acute complications of hemodialysis.

Fistula dysfunction: effect on rapid hemodialysis.

Rapid hemodialysis (Qb 400 to 500 ml/min) places considerable demands on hemodialysis vascular access. This six-month prospective study enrolled 52 patients and evaluated urea recirculation as a means of detecting fistula dysfunction. It evaluated the effects of fistula location and dialysis blood flow on urea recirculation during rapid hemodialysis and assessed the effect of rapid dialysis on fistula thrombosis. Urea recirculation increased as Qb increased from 300 to 400 ml/min (8 +/- 3% to 16 +/- 3%, P less than 0.05). The extent of urea recirculation was also fistula site dependent (radial fistulas 18 +/- 4%, upper arm fistulas 11 +/- 3%, Qb 400 ml/min, P less than 0.05). Site and blood flow dependent urea recirculations were an indicator of venous stenoses. When venous stenoses were corrected, urea recirculation rates improved (36 +/- 3% to 21 +/- 3%, P less than 0.05). There were no differences between methods of determining urea recirculation early in dialysis (contralateral arm venepuncture vs. stop flow technique; 30 to 60 min). However, at 120 minutes urea recirculation was significantly greater with the contralateral arm venepuncture technique. Venous dialysis pressure at Qb 400 ml/min had limited use as a predictor of venous stenoses unlike its value at lower Qb. Fistula thrombosis (0.26/patient year of dialysis) and fistula replacement (0.09/patient year of dialysis) were similar to our observations in a conventional hemodialysis facility where prospective correction of fistula dysfunction was also used.

Lateral ligamentous instability of the ankle: a method of surgical reconstruction by a modified Watson-Jones technique.

Forty-nine cases of lateral ligamentous instability of the ankle have been reviewed. Forty-one have been personally examined. Eight have been evaluated by questionnaire follow-up. The end results have been universally good. The results have been based on a subjective evaluation by the patient, 92% regarding the end results of the procedure to be excellent. In regard to function, 92% of the patients have been able to resume their preinjury activity. The evidence of instability of the ankle joint can be determined by preoperative x-ray examination. However, careful history and physical examination obviate the need for x-ray studies in most cases. Operative findings have confirmed our preoperative evaluation in all cases. The modification of the Watson-Jones procedure, using the peroneus longus, enables the operating surgeon use of a much greater tendon in reconstruction of the lateral ligamentous structures. No change in the function of the foot has been noted in the reported cases.

The excretion of ibuprofen by the horse - a preliminary report.

The anti-inflammatory drug Ibuprofen [(+/-)-2-(p-isobutylphenyl) propionic acid] was estimated in the blood and urine of a horse using gas-liquid chromatography of the silylated derivative. Levels of the drug in the two body fluids were measured over a period of about 24 hours after administering a 12 gm dose of Ibuprofen. Plasma peak levels were observed within 30 to 60 min, and the drug was no longer detectable in the plasma by 8 hr. Urinary peak levels were observed 200 to 300 min after dosing, and the drug was no longer detectable in the urine by about 28 hr. It was observed that only 2% to 6% of the free unchanged drug was excreted in the urine.