Comparison of systemic reactions in rush, cluster, and standard-build aeroallergen immunotherapy.

BACKGROUND: Given the choice of standard, cluster, and rush build-up for aeroallergen immunotherapy, standard-build immunotherapy has generally been preferred because of a perceived high rate of systemic reactions (SRs) associated with cluster and rush immunotherapy. OBJECTIVE: To characterize the incidence of SRs during standard, cluster, and rush build-up immunotherapy in an allergy practice during a 5-year period. METHODS: A retrospective review was conducted among patients receiving standard-build, 8- to 10-step cluster, or 2-day rush immunotherapy from January 1, 2010, through December 31, 2014, at Family Allergy & Asthma clinics in Louisville, Kentucky. Investigators excluded reactions that occurred during skin prick testing, venom immunotherapy, and not-true SRs, and identified the build-up method, age, sex, date of reaction, vial concentration, and presence of asthma. Per-shot and per-patient incidence of SRs was computed from these data. RESULTS: During our review period, 2,549,643 injections were administered to 11,982 patients. Per-shot incidence of SR was 0.01%, 0.06%, and 0.33% for standard, cluster, and rush immunotherapy, respectively; per-patient incidence of SR was 2.84%, 2.52%, and 11.86% for standard, cluster, and rush immunotherapy, respectively. A total of 42% of SRs were grade 1, 43% were grade 2, 12% were grade 3, and 3% were grade 4. No fatalities were reported. A total of 70% of total SRs, 75% of cluster SR, and 55% of rush SR occurred in females, with an emergent peak in SR from May to October. CONCLUSION: Compared with previously published rates, we observed a decrease in the incidence of SR for standard, cluster, and rush immunotherapy, with peak seasonality from May to October and a female predominance.

Development of a standardized method for motion testing in pulse oximeters.

BACKGROUND: Pulse oximeter performance in the presence of motion varies among devices and manufacturers because of variations in hardware, software, testing, and calibration. Compounding these differences is a lack of uniform characterization of motion, and the consequential effects of motion upon the wide range of normal and abnormal human physiology. Traditional motion testing attempts to standardize motion into a reproducible form by using a mechanical jig to produce passive motion of a known amplitude and frequency. This type of motion challenge fails to account for the physiologic changes induced by active movement. METHODS: We postulate that a more appropriate method for testing the performance of pulse oximeters in the presence of motion is to create a feedback control loop between the device and the test subject, providing a reproducible, actively created, and controlled motion test suitable for standardized testing among manufacturers. It is hoped that relying on a signal as seen from the oximeter's perspective will enable the creation of a sensitive and reproducible test method capable of separating those oximeters that can reject motion artifact from those that cannot. RESULTS: Preliminary results have concentrated on building the tools and clinical protocols needed to evaluate this method. Some basic observations are reported, but insufficient numbers of experienced subjects precludes rigorous conclusions. CONCLUSION: We have set the stage for a feasibility demonstration using a novel form of testing. With sufficient subjects and proper statistical evaluation, a robust test method for assessing the performance of pulse oximeters in the presence of motion may be at hand.