Single-Center Experience of Deep Sedation With Non-Anesthesia Trained EP Lab Personnel: It's About Time

The EP lab at Providence Hospital in Southfield, Michigan, has been using deep sedation for over eight years without anesthesia. There have been many articles about the use of conscious sedation and far less deep sedation for various procedures in the clinical electrophysiology setting without the use of anesthesia personnel. What set our department apart was the fact that we use a medication called propofol (Diprivan). In Michigan, this medication is used almost exclusively by anesthesia. All the literature that we researched, whether using conscious sedation or deep sedation without the use of anesthesia, used only benzodiazepines and opiates. Due to the scant data on this subject, our team decided to do a research abstract, which was accepted and presented recently at the annual Heart Rhythm Society conference in Boston.¹ The goal of our study was to determine whether our practice of using deep sedation with propofol without anesthesia was safe in the EP clinical setting. Propofol, a central nervous system depressor classified as a deep sedation medication with a very short half-life, was the pivotal point of our research. Most clinical settings use benzodiazepines and opiates to create a moderate sedation level in which the patient is awake and responsive. Another goal is pain control. The patient may or may not remember the procedure, but the primary aspect of this level of sedation is that the patient is able to protect their own airway and maintains a stable respiratory rate with any intervention from the clinical staff. This level of sedation is given the classification conscious sedation. The level of sedation used in our lab renders the patient completely unconscious. Our lab uses benzodiazepines, opiates and propofol to achieve this level of sedation. The short half-life of propofol gives us excellent control over the patient's sedation level. Benzodiazepines and opiates when used alone are difficult to control due to their prolonged half-life. A patient achieving this level of sedation, called deep sedation, using these agents may have difficulties post procedure when they are out of the clinical area. If the patient has limited respiratory drive and is unable to protect their airway, immediate intervention may be required to support the patient. Our medical director, Dr. Christian Machado, came to our hospital to establish an EP program in 1998. He was trained in deep sedation in Florida and incorporated this practice in the program he started. The staff is trained in advanced airway support and medication administration internally at the Heart Institute. Anesthesia personnel are available if needed and respond immediately. This practice has proven effective for patient care. As an added benefit, case flow is improved because there is no need to coordinate two departments for a case. Our department has an EP lab and an implant lab. The staff consists of five staff members who are cross-trained for all positions. We employ both RNs as well as technologists. If more staff is required for a case, we draw staff from our cardiac cath labs that have been cross-trained to EP. We use three team members for all cases in an unusual way, compared to most invasive cardiology settings. The person administering the medications is responsible only for patient care. That individual only monitors and medicates the patient, as compared to most settings, where they would also be assisting with the procedure by dropping supplies and other duties. They are responsible for knowing the patient's history in-depth. The second person may be a staff member or one of our cardiology fellows. That person then scrubs in with the electrophysiologist and assists with the procedure itself. The third person runs the EP recording equipment and assists the procedure by dropping supplies and organizing the procedure room as well as assisting the staff member who is sedating the patient. This allows our sedation staff member to be totally dedicated to the care of the patient. Our retrospective analysis looked at cases from two other departments, endoscopy and the cardiac cath lab, using conscious sedation during the period from January 2004 to November 2005, and compared them with the same time period to patients in the EP lab. Over 18,000 patients were reviewed in the other two departments. Over 900 patients were reviewed in the EP lab. The only inclusion criterion was that the patient received some form of sedation. There was no exclusion criterion. An incident was defined as a Reportable Adverse Reaction as defined by our hospital's sedation committee, which reviews all sedation cases and sets standards of care for sedation in the hospital outside of the anesthesia department. We demonstrated that using propofol was safe and effective in this setting without the use of anesthesia personnel. A rate of adverse incidents was determined per 1,000 cases. For the two departments using conscious sedation only, the rate of adverse incidents was 1.61 per 1,000 cases. The rate of adverse incidents for the EP lab when using deep sedation alone was 1.28 per 1,000 cases. When combining conscious sedation and deep sedation, the rate of adverse incidents was 1.09 per 1,000 cases. Due to the small number of events, statistical significance was not determined. Patients who received deep sedation in the EP lab were 1.5 times less likely of an adverse event as compared to conscious sedation in the endoscopy and cardiac cath labs (OR = 0.65). The preventive risk of complications was 0.33 events per 1,000 cases when comparing the two settings. There were no adverse events and we had only one incident during that time period, and that was due to a patient who was a poor historian and limited documentation from the referring physician. The case was abandoned with no long-term harm to the patient. The patient was then admitted for his co-morbid medical conditions. These were treated and the patient returned to the EP lab several days later with no problems or adverse reactions. We firmly realize and acknowledge that there is an increased risk to the patient when using deeper sedation. However, the risk to the patient is still less than that of the patient receiving lower levels of sedation in other areas of the hospital. When using similar levels of sedation, conscious sedation, there is a significant decrease in the risk to patients in the EP lab. We hypothesize that this is due to the high degree of training, strict protocol compliance, continuous quality improvement monitoring, and that the staff responsible for sedating the patient is completely dedicated to the patient's care.