Biomedical instrumentation & technology / Association for the Advancement of Medical Instrumentation
-
Biomed Instrum Technol · May 1998
FDA recognition of consensus standards in the premarket notification program.
"The FDA has long advocated the use of standards as a significant contributor to safety and effectiveness of medical devices," Center for Devices and Radiological Health's (CDRH) Donald E. Marlowe and Philip J. Phillips note in the following article, highlighting the latest U. ⋯ In implementing the legislation, the FDA published in the Federal Register a list of standards to which manufacturers may declare conformity. Visit AAMI's Web site at www.aami.org/news/fda.standards for a copy of the list and for information on nominating other standards for official recognition by the agency. The FDA expects that use of standards will benefit the agency and manufacturers alike: "We estimate that in time, reliance on declarations of conformity to recognized standards could save the agency considerable resources while reducing the regulatory obstacles to entry to domestic and international markets," state the authors.
-
Biomed Instrum Technol · Mar 1998
A new approach to acoustical evaluation of human respiratory sounds.
The authors developed a method for more precise detection and analysis of the physical features of respiratory and voice sound transmission to the chest wall. Based on their findings using this method, they designed several devices for acoustic examination and evaluation of components of human respiratory sounds. These devices analyze forced expiratory sounds, distinguish between air-borne and structure-borne sounds, and distinguish abnormalities in voice transmission to the chest wall. Tests of the devices on human subjects confirmed the validity of the authors' theoretical models, which offer promise for the development of a new class of medical diagnostic instruments.
-
Biomed Instrum Technol · Jan 1998
Vector magnitude using orthogonal ECG leads during ventricular fibrillation is associated with defibrillation outcome.
Random fluctuations of ventricular fibrillation (VF) affect defibrillation; in addition, the heart is more susceptible to defibrillation at a higher absolute VF voltage (AVFV). Shocks delivered at higher AVFV waveforms from a single lead of the electrocardiogram (ECG) are more effective than conventional shocks. The authors investigated a new sensing method using multiple leads for better representation of the depolarization state of the heart. ⋯ This further confirms that a susceptible period for defibrillation occurs during VF. The hardware/software design satisfied the requirements for processing the VF vector waveform in real time, and with the help of signal-processing techniques the high VF voltage could be detected at it occurred in real time. In addition, the P2 defibrillation lead configuration was significantly better than the P1 (p < 0.006).