Efficacy and safety of sedation in cardiac imaging

Implication for health policy/practice/research/medical education: It is vital that non-anesthesiologist sedation practitioners responsible for intravenous sedation management have appropriate training and skills. A suitable monitoring system must be available during the procedure, and necessary support must be provided by an assistant for the observation of vital signs and management of the airway. Copyright © 2014, Iran University of Medical Sciences; Published by Kowsar Corp. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Nowadays, cardiac imaging is provided via numerous modalities such as echocardiography [transesophageal echocardiography (TEE) and transthoracic echocardiography (TTE)], magnetic resonance imaging of the heart (cardiac MRI), cardiac nuclear study, cardiovascular computed tomography (CT) scan-angiography, carotid artery imaging, and general radiography. Also, an increasing number of adult or pediatric patients currently undergo minimally invasive cardiovascular diagnostic or interventional procedures in catheterization and electrophysiology laboratories. These diagnostic imaging modalities are time-consuming and cooperation-dependent, and the creation of the best examination environment along with adherence to the best “patient safety” standards necessitates the application of most recent sedation guidelines and patient monitoring protocols (1). TEE is a valuable diagnostic method performed for an increasing number of patients in echocardiography laboratories, operating rooms, and intensive care units. Although generally a safe procedure, TEE is regarded as a semi-invasive modality due to its potential for some minor and rarely major complications (1). It is, therefore, essential that TEE be conducted by a highly skilled operator. This imaging technique often requires light degrees of sedation and analgesia. The European Society of Cardiology (ESC) provides clear-cut guidelines for the appropriate premedication and establishment of a standard monitoring system prior to a TEE examination (2). These guidelines are, however, proposed only for TEE in adults and there are other protocols for pediatric patients. The majority of patients need only conscious sedation, which has the benefit of speedy post-procedural recovery and early discharge from the echocardiography laboratory. A large number of patients who receive conscious sedation, must be informed that they will not get a complete anesthetic (3). The personnel in charge of TEE must know that every drug, which depresses the central nervous system, could impair ventilation, circulation system, or both. Therefore, it is necessary that non-anesthesiologist sedation practitioners managing intravenous sedation regularly pass relevant training courses (4). Electrocardiography (ECG) and oxygenation monitoring must be available throughout the procedure, and support must be provided by an assistant for the observation of vital signs and management of the airway (3, 5). This assistant can be an anesthesiologist, a well-trained anesthesia nurse, or any physician familiar with the pharmacology and clinical use of sedative/analgesic drugs and able to manage the patient’s airway and lung ventilation as necessary (3). TEE should not be a painful procedure, and it is essential to remember that tranquilizers do not alleviate pain. Pain in a TEE examination can be a sign of a possible complication (i.e. esophageal erosion) (1, 2, 6).