Measuring Plasma Conductivity to Detect Sodium Load in Hemodialysis Patients

Background: Sodium thiosulfate therapy has been proposed for calcific uremic arteriolopathy and nephrogenic systemic fibrosis in hemodialysis patients. The treatment brings 3.7 g (161 mmol) of sodium. How to counterbalance this sodium load was studied.Design, setting, participants, & measurements: Plasma conductivity (Cp) and mass balance index were compared for 20 sessions without thiosulfate and 20 sessions with thiosulfate infusion. Subsequently, the dialysate conductivity was set to 13.8 mS/cm during the entire session. Next, dialysate conductivity was set to 14 mS/cm for the first 3 h and to 13 mS/cm for the last hour of thiosulfate infusion (n = 25).Results: The Cp variation between beginning and end was equal to +0.005 ± 0.13 mS/cm without thiosulfate, +0.24 ± 0.13 mS/cm with thiosulfate, and 14 mS/cm dialysate conductivity (P < 0.001). The decrease in dialysate conductivity at 13.8 mS/cm did not counterbalance the sodium load. The last program adequately compensated the sodium load with a Cp increase of only +0.05 ± 0.14 mS/cm (NS versus without thiosulfate). The total of the dialyzed sodium and the sodium load for this last program was equal to 603 mmol compared with 456 mmol for the sessions without thiosulfate, the difference of 147 mmol being close to the known content of 161 mmol in 25 g of infused thiosulfate.Conclusions: Thiosulfate infusion requires a decrease of dialysate conductivity of −1 mS/cm during the infusion to counterbalance the added 3.7 g (161 mmol) sodium load.Sodium thiosulfate treatment has been proposed to treat calcific uremic arteriolopathy in hemodialysis patients (1–4) and recently for nephrogenic systemic fibrosis (5). The dose is 25 g/1.73 m² per hemodialysis session during the last 60 min. The formulation of sodium thiosulfate is Na₂S₂O₃·(H₂O)₅ and the infusion of this amount of thiosulfate brings a clinically significant sodium load. The calculated sodium load for 25 g of thiosulfate is 3.7 g (161 mmol), corresponding to the amount of sodium contained in 1 L of isotonic sodium chloride infusion.The two patients that underwent the thiosulfate treatment had developed severe calcific uremic arteriolopathy of the extremities. We decided to use sodium thiosulfate at a dose of 25 g per dialysis session. As we started the thiosulfate therapy, we rapidly noticed that the infusion induced a notable increase in plasma conductivity (Figure 1). Hence we recorded the plasma conductivity variation during the dialysis sessions under thiosulfate for the two patients and we modified the dialysate treatment to counterbalance the sodium load.Open in a separate windowFigure 1.Example of a plasma conductivity curve during a dialysis session with thiosulfate infusion during the last hour of dialysis. Dialysate conductivity was kept constant at 14.0 mS/cm.     

Questions to improve family–staff communication in the ICU: a randomized controlled trial

Purpose

Relatives of intensive care unit (ICU) patients suffer emotional distress that impairs their ability to acquire the information they need from the staff. We sought to evaluate whether providing relatives with a list of important questions was associated with better comprehension on day 5.

Methods

Randomized, parallel-group trial. Relatives of mechanically ventilated patients were included from 14 hospitals belonging to the FAMIREA study group in France. A validated list of 21 questions was handed to the relatives immediately after randomization. The primary endpoint was comprehension on day 5. Secondary endpoints were satisfaction (Critical Care Family Needs Inventory, CCFNI) and symptoms of anxiety and depression (Hospital Anxiety and Depression Scale, HADS).

Results

Of 394 randomized relatives, 302 underwent the day-5 assessment of all outcomes. Day-5 family comprehension was adequate in 68 (44.2%) and 75 (50.7%) intervention and control group relatives (P?=?0.30), respectively. Over the first five ICU days, median number of family–staff meetings/patient was 6 [3–9], median total meeting time was 72.5 [35–110] min, and relatives asked a median of 20 [8–33] questions including 11 [6–13] from the list, with no between-group difference. Satisfaction and anxiety/depression symptoms were not significantly different between groups. The only variable significantly associated with better day-5 comprehension by multivariable analysis was a higher total number of questions asked before day 5.

Conclusions

Providing relatives with a list of questions did not improve day-5 comprehension, secondary endpoints, or information time. Further research is needed to help families obtain the information they need.

Trial registration

ClinicalTrials.gov Identifier: NCT02410538.

     

Field evaluation of clinical features during chikungunya outbreak in Mayotte, 2005–2006

Background To record and assess the clinical features of chikungunya fever (CHIKF), with a view to enable diagnosis based on clinical criteria rather than costly laboratory procedures in field conditions. Methods As part of a cross‐sectional serologic survey conducted in Mayotte after a massive chikungunya outbreak in 2006, we collected data on clinical features of chikungunya infection and assessed the performance and accuracy of clinical case definition criteria combining different symptoms. Results Of 1154 participants included, 440 (38.1%) had chikungunya‐specific IgM or IgG antibodies by enzyme‐linked immunosorbent assay (ELISA). Of symptomatic participants, 318 (72.3%) had confirmed chikungunya, the dominant symptoms reported were incapacitating polyarthralgia (98.7%), myalgia (93.1%), backache (86%), fever of abrupt onset (85%) and headache (81.4%). There was a strong linear association between symptomatic infection and age (χ² for trend = 9.85, P < 0.001). Only 52% of persons with presumptive chikungunya sought medical advice, principally at public primary health care facilities. The association of fever and polyarthralgia had a sensitivity of 84% (95% CI: 79–87) and a specificity of 89% (95% CI: 86–91). This association allowed to classify correctly 87% (95% CI: 85–89) of individuals with serologically confirmed chikungunya. Conclusions Our results suggest that the pair fever and incapacitating polyarthralgia is an accurate and reliable tool for identifying presumptive CHIKF cases in the field. These criteria provide a useful evidence base to support operational syndromic surveillance in laboratory‐confirmed chikungunya epidemic settings.     

Therapeutic myocardial angiogenesis

Armed with an improved understanding of the mediators of angiogenesis, physicians and scientists have made significant efforts at harnessing this naturally occurring process in order to treat patients with a variety of peripheral vascular and coronary ischemic syndromes. There is a growing population of patients with end-stage coronary artery disease (CAD) who are no longer candidates for mechanical revascularization, yet suffer from chronic myocardial ischemia who may benefit from regeneration of the depleted microvasculature.     

Characterization and PCR multiplexing of 14 new polymorphic microsatellite loci for the invasive subantarctic carabid Merizodus soledadinus (Coleoptera: Carabidae)

Seventeen novel microsatellite markers were characterized from an enriched DNA library for the invasive carabid beetle Merizodus soledadinus. Loci were tested, as parts of two multiplex sets in 48 M. soledadinus from 2 populations. 14 loci gave reliable amplification, and genetic diversity ranged from 2 to 6 alleles per locus. In other species of the supertribe trechitae, 8 loci reliably amplified in Eotachys bistriatus, whereas all failed for Trechisibus antarcticus and Trechus obtusus.     

Low-Frequency Electric Muscle Stimulation Combined With Physical Therapy After Total Hip Arthroplasty for Hip Osteoarthritis in Elderly Patients: A Randomized Controlled Trial

Gremeaux V, Renault J, Pardon L, Deley G, Lepers R, Casillas J-M. Low-frequency electric muscle stimulation combined with physical therapy after total hip arthroplasty for hip osteoarthritis in elderly patients: a randomized controlled trial.

Objective

To assess the effects of low-frequency electric muscle stimulation associated with usual physiotherapy on functional outcome after total hip arthroplasty (THA) for hip osteoarthritis (OA) in elderly subjects.

Design

Randomized controlled trial; pre- and posttreatment measurements.

Setting

Hospital rehabilitation department.

Participants

Subjects (N=29) referred to the rehabilitation department after THA for hip OA.

Interventions

The intervention group (n=16; 78±8y) received simultaneous low-frequency electric muscle stimulation of bilateral quadriceps and calf muscles (highest tolerated intensity, 1h session, 5 d/wk, for 5 weeks) associated with conventional physical therapy including resistance training. The control group (n=13; 76±10y) received conventional physical therapy alone (25 sessions).

Main Outcome Measures

Maximal isometric strength of knee extensors, FIM instrument, before and after; a six-minute walk test and a 200m fast walk test, after; length of stay (LOS).

Results

Low-frequency electric muscle stimulation was well tolerated. It resulted in a greater improvement in strength of knee extensors on the operated side (77% vs 23%; P<.01), leading to a better balance of muscle strength between the operated and nonoperated limb. The low-frequency electric muscle stimulation group also showed a greater improvement in FIM scores, though improvements in the walk tests were similar for the 2 groups, as was LOS.

Conclusions

Low-frequency electric muscle stimulation is a safe, well-tolerated therapy after THA for hip OA. It improves knee extensor strength, which is one of the factors leading to greater functional independence after THA.     

Congenital diaphragm weakness without neuromuscular disease

We report on two children presenting at birth with respiratory failure, bilateral diaphragmatic eventration, and floppiness. Electrodiagnostic studies of the limbs, and biochemical and DNA studies excluded generalized neuromuscular diseases. Phrenic nerve electrodiagnostic studies and electromyography of the diaphragm suggested isolated diaphragm hypoplasia. Diaphragm muscle biopsy showed a paucity of muscle fibers. Isolated hypoplasia of the diaphragm is a rare cause of neonatal respiratory failure, which may have a favorable outcome with long-term ventilatory support. Muscle Nerve, 2008.