Monitoring changes in fluid status with a wireless multisensor monitor: results from the Fluid Removal During Adherent Renal Monitoring (FARM) study.

Body fluid assessment is important for managing chronic kidney disease (CKD) and heart failure (HF). However, accurate detection of fluid retention remains elusive. The Fluid Removal During Adherent Renal Monitoring (FARM) study is a prospective, nonrandomized trial examining the performance of a wireless, noninvasive, multisensor fluid monitoring system, applied to the chest, to determine its performance and reliability during hemodialysis. Patients undergoing regular hemodialysis (n=25) were monitored continuously for 2 consecutive dialysis sessions and the interdialysis period. Physiologic variables, including tissue impedance, were recorded. The volume of fluid removed and weight change during dialysis were measured. An average of 3.4±1.2 L of fluid was removed during dialysis, which was associated with an increase in bioimpedance of 11.3±7.2 Ω. Change in bioimpedance was highly correlated with the amount of fluid removed but less so with weight loss. Normalized bioimpedance change (21.0%±12.1% increase from baseline, P<001) was larger than the normalized weight change (3.6%±1.1%, P<.01), suggesting a higher sensitivity and dynamic range than weight change for detecting fluid removal. The fluid monitoring system accurately tracked fluid and weight loss in patients during hemodialysis, supporting its use as a tool for the management of patient fluid status in disease states.

Pneumococcal conjugate vaccines as maternal and infant immunogens: challenges of maternal recruitment.

Maternal pneumococcal immunization may be a strategy for the prevention of pneumococcal disease during the first months of life before infant-administered pneumococcal conjugate vaccine (PCV) becomes protective. Preparatory to a Phase III efficacy trial to investigate this strategy for preventing early infant otitis media (OM), we are conducting a Phase I-II randomized, double-masked trial to determine if maternal 9-valent PCV immunization alters active antibody production in infants who are immunized with PCV-7 and to compare local and systemic adverse events among women immunized with PCV-9 or placebo. A pilot study was conducted in 1997 in a Minneapolis-St. Paul health maintenance organization, HealthPartners (HP), to estimate enrollment rate for the proposed Phase III trial. A total of 154 pregnant women were selected of whom 122 appeared to be eligible from ICD codes in the HP claims database; 76 responded, and 46 of these were eligible for participation. Four of the 46 reported that they would be very likely and 21 somewhat likely to participate; an estimated 20% (25/122) participation rate. The records of 4,289 women in their second trimester have been reviewed to date for the Phase I/II trial; 2,589 (60%) were found not to be eligible; and an additional 1,015 (24%) could not be contacted. Of the 685 remaining, 558 (81%) were not interested in participating when interviewed, and 127 (19%) have consented. Most (46%) of those who declined participation have cited concern about the safety of vaccination during pregnancy. While the overall participation rate of second trimester women is only 3% (127/4,289), maternal attrition (2.8%) and infant attrition from the study before age 7 months (3.9%) are lower than projected (25%). Differences in study design could explain the difference in participation rates estimated in the pilot study and experienced in the Phase I/II study. Reports of safety from large-scale studies of maternal PCV immunization in industrialized countries are needed before women are receptive to maternal immunization to protect their infants against pneumococcal disease.