Elevated visual dependency in young adults after chemotherapy in childhood

Chemotherapy in childhood can result in long-term neurophysiological side-effects, which could extend to visual processing, specifically the degree to which a person relies on vision to determine vertical and horizontal (visual dependency). We investigated whether adults treated with chemotherapy in childhood experience elevated visual dependency compared to controls and whether any difference is associated with the age at which subjects were treated. Visual dependency was measured in 23 subjects (mean age 25.3 years) treated in childhood with chemotherapy (CTS) for malignant, solid, non-CNS tumors. We also stratified CTS into two groups: those treated before 12 years of age and those treated from 12 years of age and older. Results were compared to 25 healthy, age-matched controls. The subjective visual horizontal (SVH) and vertical (SVV) orientations was recorded by having subjects position an illuminated rod to their perceived horizontal and vertical with and without a surrounding frame tilted clockwise and counter-clockwise 20° from vertical. There was no significant difference in rod accuracy between any CTS groups and controls without a frame. However, when assessing visual dependency using a frame, CTS in general (p = 0.006) and especially CTS treated before 12 years of age (p = 0.001) tilted the rod significantly further in the direction of the frame compared to controls. Our findings suggest that chemotherapy treatment before 12 years of age is associated with elevated visual dependency compared to controls, implying a visual bias during spatial activities. Clinicians should be aware of symptoms such as visual vertigo in adults treated with chemotherapy in childhood

A TURBO PASCAL PROGRAM TO CONVERT ICD-9CM CODED INJURY DIAGNOSES INTO INJURY SEVERITY SCORES - ICDTOAIS

Diagnoses of injuries as a result Of trauma are commonly coded by means of the International Classification of Diseases (9th rev.) Clinical Modification (ICD-9CM). The Abbreviated Injury Scale (AIS) is frequently employed to assess the severity of injury per body region. The Injury Severity Score (ISS) is an over-all index or summary of the severity of injury. To compute one of these two types of scores the entire medical record of each patient must be examined. The program ICDTOAIS replaces the manual coding or translation between the two scores. The program converts the ICD-9CM coded diagnoses into AIS and ISS scores. The program also computes the maximum AIS (MAXAIS) per body region, enabling the researcher to assess the relative impact of the severity of trauma of different body regions in both morbidity and mortality studies. The program locates invalid ICD-9CM rubrics in the data file. ICDTOAIS may be employed as a program alone or as a procedure in database management systems (e.g., DBase III plus, DBase IV, or the different versions of FOX-PRO). The program is written in Turbo Pascal, Version 6

Membrane biocompatibility does not affect whole body protein metabolism during dialysis

Background: Protein-calorie malnutrition is present in 30-50% of dialysis patients. The lack of biocompatibility of the dialysis membrane, which results in low-grade inflammation, could be responsible for this malnutrition. We investigated whether protein-energy malnutrition could be partly due to incompatibility of the dialyzer during the dialysis session. Methods: Five patients were dialyzed during 2 periods of 3 weeks (cross-over) with either a single-use low-flux polysulfone or cellulose triacetate (biocompatible) or a single-use cuprophan (bio-incompatible) membrane. As a measure of whole body protein metabolism, a primed constant infusion of L-[1-C-13]-valine was used during a 4-hour dialysis session. Results: Cuprophan was a more powerful activator of the complement system than other membranes. Protein metabolism parameters during both study protocols were not different and resulted in the same protein balance during polysulfone/cellulose triacetate (-15 +/- 3) and cuprophan (-13 +/- 2 mu mol/kg/h) dialysis. Conclusion: In stable hemodialysis patients with no apparent complications, protein metabolism during dialysis is not affected by the compatibility of the dialysis membrane. Copyright (C) 2005 S. Karger AG, Basel

Comparison of amino acid oxidation and urea metabolism in haemodialysis patients during fasting and meal intake

Background. The PNA (protein equivalent of nitrogen appearance) is used to calculate protein intake from urea kinetics. One of the essential assumptions in the calculation of PNA is that urea accumulation in haemodialysis (HD) patients is equivalent to amino acid oxidation. However, urea is hydrolysed in the intestine and the resulting ammonia could be used metabolically. The magnitude and dependence on protein intake of this process are unknown in HD patients. Methods. Seven HD patients were studied twice, 1 week apart, on a similar protocol. After an overnight fast, patients fasted in the morning and received meals in the afternoon. On one day, amino acid oxidation was measured by infusion of L-[1-C-13]valine. Urea production, measured from the dilution of [C-13]urea, and urea accumulation, calculated from the increase in plasma urea concentration multiplied by the urea dilution volume, were measured during the other day. PNA was calculated using standard equations. Results. Amino acid oxidation and urea production were not significantly different during fasting. Urea accumulation during fasting was significantly lower than both amino acid oxidation and urea production. Urea accumulation during feeding remained significantly lower than amino acid oxidation. PNA was equal to the average of the urea accumulation values during fasting and feeding. Conclusion. We conclude that during fasting, urea accumulation is not associated with amino acid oxidation or urea production. During meal intake, amino acid oxidation, urea production and urea accumulation show acutely an almost identical increase. PNA represents the average of fasting and fed urea accumulation and is lower than average amino acid oxidation or urea production

Oxidative metabolism appears to be reduced in long-term hemodialysis patients

Background. As part of a study of whole-body protein metabolism in hemodialysis (HD) patients, we obtained values for whole-body bicarbonate production in control subjects and HD patients before and during dialysis by using stable isotopically labeled bicarbonate. Indirect calorimetry measurements have shown normal or increased energy expenditure in HD patients, which has been used to explain the malnutrition in many of these patients. However, this method becomes inaccurate when the dynamics of whole-body bicarbonate production change during measurement, as is the case with HD patients during dialysis. Methods: Whole-body bicarbonate production was measured in 6 control subjects, 9 patients on a nondialysis day (HD-), and 8 patients during an HD session (HD+) by means of a primed constant infusion of carbon 13 (C-13)-labeled sodium carbonate ((NaHCO3)-C-13). 13 C-Abundance of expired carbon dioxide was measured by means of isotope ratio mass spectrometry. Results Carbon dioxide production was 141 +/- 12, 123 +/- 11(star), and 148 +/- 19 mu mol/kg/min for the control, HD-, and HD+ groups, respectively (P-star <0.05 compared with the control and HD+ groups). Values for energy expenditure were derived and were 29.1 +/- 2.4, 24.9 +/- 2.1(star), and 32.6 +/- 2.0 kcal/kg/day, respectively (P-star <0.05 compared with the control and HD+ groups). Conclusion: Whole-body oxidation in HD patients is reduced compared with control subjects. During dialysis, bicarbonate turnover, as well as carbon dioxide expiration, increases because of the influx of bicarbonate from the dialyzer. (c) 2005 by the National Kidney Foundation, Inc

A comparison of rate control and rhythm control in patients with recurrent persistent atrial fibrillation

Background: Maintenance of sinus rhythm is the main therapeutic goal in patients with atrial fibrillation. However, recurrences of atrial fibrillation and side effects of antiarrhythmic drugs offset the benefits of sinus rhythm. We hypothesized that ventricular rate control is not inferior to the maintenance of sinus rhythm for the treatment of atrial fibrillation. Methods: We randomly assigned 522 patients who had persistent atrial fibrillation after a previous electrical cardioversion to receive treatment aimed at rate control or rhythm control. Patients in the rate-control group received oral anticoagulant drugs and rate-slowing medication. Patients in the rhythm-control group underwent serial cardioversions and received antiarrhythmic drugs and oral anticoagulant drugs. The end point was a composite of death from cardiovascular causes, heart failure, thromboembolic complications, bleeding, implantation of a pacemaker, and severe adverse effects of drugs. Results: After a mean (+/-SD) of 2.3+/-0.6 years, 39 percent of the 266 patients in the rhythm-control group had sinus rhythm, as compared with 10 percent of the 256 patients in the rate-control group. The primary end point occurred in 44 patients (17.2 percent) in the rate-control group and in 60 (22.6 percent) in the rhythm-control group. The 90 percent (two-sided) upper boundary of the absolute difference in the primary end point was 0.4 percent (the prespecified criterion for noninferiority was 10 percent or less). The distribution of the various components of the primary end point was similar in the rate-control and rhythm-control groups. Conclusions: Rate control is not inferior to rhythm control for the prevention of death and morbidity from cardiovascular causes and may be appropriate therapy in patients with a recurrence of persistent atrial fibrillation after electrical cardioversion

The metabolic response to ingested protein is normal in long-term hemodialysis patients

Background Protein-energy malnutrition affects 30% to 50% of hemodialysis (HD) patients. This has been attributed to inadequate food intake, but may be caused by disturbances in utilization of ingested protein. Methods: We studied protein kinetics during fasting and during ingestion of a protein-enriched meal to investigate possible metabolic differences between stable HD patients and control subjects. Whole-body protein kinetics was measured by means of a primed constant infusion of L[1-C-13] valine. Results: During fasting, whole-body protein balance was significantly less negative in HD patients compared with control subjects. During meal intake, protein balance was similar between HD patients and control subjects. Meal intake increased protein balance significantly in both groups, but not differently between the groups. Also, protein oxidation was decreased during fasting in HD patients compared with control subjects, but not during meal intake. Conclusion: We conclude that the rate of protein breakdown is lower in HD patients compared with control subjects, but the efficiency of protein utilization is normal in HD patients during a nondialysis day