This book is designed to introduce the reader to the fundamental information necessary for work in the clinical setting, supporting the technology used in patient care. Beginning technicians/ technologists can use this book to develop a working vocabulary and fundamental knowledge of the Healthcare Technology Management (HTM) profession. Content includes a wide variety of medical technology, with an emphasis on device types and classifications; individual manufacturers are utilized as examples.

This work is intended for the reader with a fundamental understanding of anatomy, physiology, and medical terminology appropriate for their role in the healthcare field, and assumes the reader's understanding of electronic concepts, including voltage, current, resistance, impedance, analog and digital signals, and sensors. The material covered in this book will assist the reader in the development of his or her role as a knowledgeable and effective member of the patient care team. The second edition features revisions to all of the content to reflect changes in healthcare, regulations, standards, and technology. A new chapter addresses device testing, with emphasis on safety inspections. A second new chapter explores the interface of medical technology with the electronic medical record.

A vital connection exists between technology and the care of patients. In many cases, healthcare workers depend on technology to administer care or treatment or to make a diagnosis. This book helps readers understand how technology is tightly woven into patient care. The role of technical support for the medical team is, therefore, essential in the delivery of effective medical care.

The section of each chapter entitled “For Further Exploration” encourages readers to use the Internet to obtain in- depth information about a related topic. The questions are designed to push the reader to integrate concepts and ideas using external sources. Answers to the questions are not specifically available within the chapters. Research exercises encourage one of the most important professional skills – the ability to investigate topics that are not well understood. In the clinical setting, it is virtually impossible to be an expert about all technology and aspects of patient care. The ability to effectively search for information is vital.

Introduction

Technology is used to support heart function in numerous ways. Perhaps the most common and well- known device is the defi- brillator. In addition, the amazing life- saving powers of artificial hearts and implantable devices regularly capture the attention of the public and news media.

ACLS (advanced cardiac life support) is a detailed protocol to provide life- saving cardiac care. HTM professionals may be involved in the selection of technology and technical protocols used in a crisis. In addition, technicians may help establish training programs and awareness of the medical devices involved in emergency response.

Defibrillators

A defibrillator is familiar to most only from life- saving moments on television medical shows, but is often used in real life as first responders seek to help those with medical emergencies. It is a fairly simple device that delivers a large amount of energy across a patient's chest when the heart is not beating properly: that is, when the pacemaker of the heart, the sinoatrial (SA) node is not properly generating a periodic waveform. When the heart is not beating with a pattern, all cells are contracting at different times, this is known as fibrillation. Defibrillators, or defibs (as they are often called) in use today send about 3,000 volts (V) – up to 20 amperes (A) – across a patient's chest. (Note: The amount of voltage and current vary tremendously based on the patient's size and therapeutic settings.) This large amount of energy causes all cells in the heart to depolarize at once. This action may allow the SA node to resume function and generate a normal electrical pattern. Sometimes the SA node can recover and resume electrical control of the heart, but sometimes it cannot. The shape of the energy waveform delivered by a defibrillator has evolved with experience. The Lown waveform was the therapeutic waveform standard until recently. It looks like a damped sine wave.

The biphasic waveform is the standard of care in defibrillators today. It has both a positive and negative component and produces much better results for patients more quickly. Because it better simulates the electrical conduction pattern through the heart, biphasic waveforms are able to deliver results with less energy. The waveform is approximated in Figure 8.1.