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Email Discussion Group: Daily QA on Imaging Equipment

Prior to the cineless systems, QA was done on processing equipment and on imaging equipment. The primary reasons were to detect any changes in the cineradiographic equipment for radiation safety guidelines. I spoke with our medical physicist, who checks the dosage levels once a year. He understood how a daily QA program is needed. If there is a shift in radiation dosage levels, the end result is unnecessary direct ionizing radiation exposure to the patient and and scatter to the personnel in the room. If the dose did change, it could go undetected for a year. How many workers know the amount of radiation per cine frame on each image intensification mode and how many know the fluoroscopic dose levels in the different image intensifier modes? What is the maximum R/min for pulsed and non-pulsed fluoroscopy? I recently read an article on radiation safety in a northeastern U.S. cath lab. Their policy is to check all patients who have had 20 minutes or more of fluoroscopy during an invasive (interventional) cardiology procedure for any evidence of erthyema. The article did not mention the latent time intervals. If a fluoroscopic dose level on a patient was 4 R/min and the total fluoroscopy time was 60 minutes, the total entrance dose to the immediate back of the table before entering the patient’s thorax would be 240 R/hr. (240,000 mR/hr. or 2400 Gy). If anyone has any policies and procedures on quality assurance of filmless cinefluoroscopic equipment, please consider sharing them. (Thank you to Chuck Williams RT(R)(CV), RCIS, CPFT, RPA Student, Weber State University, Radiologic Sciences, Ogden, Utah, for our last email discussion group question, above). We have been cineless for so long that most of my technologists cannot remember doing a daily QA, and those that do, believed that it was done mainly for the processors in the cath lab. This was done to ensure that all chemicals meet specifications prior to the developing of film. The world of digital should make it easy to check all or any dosing questions you need to have answered. I would recommend you talk with your manager about doing a daily query on the items most concerning you and your patients. The equipment we use (Siemens) allows you to review everything that happened during every patient seen, as far back as you like. You could also simplify your query by just querying the Total Dose Area by cGYcm2. Scott Fylling, Manager of Cardiac Cath, Special Procedures Scott.Fylling@bhsnet.org Scott (above): We have all the same info on all of our systems. The physicist checked all four rooms. All exceeded state and federal limits. The engineers had assured everyone everything was okay. The physicist checks the system once a year. In my experience, QA was done to verify any variances in processing and at the same time, it verified any fluctuations in the cineradiography equipment. Most recently, we installed a new flat panel system. The engineers told us we would be using less radiation, but this has not turned out to be true, and no one has surfaced with a way to QA the systems daily. Even though the units give you the total fluoro doses and cine doses, how do you know if the system has drifted? Chuck Williams, Codywms@msn.com Chuck (above): You can query any perimeters you deem important, then let the system tell you what cases fall outside those perimeters. Scott Fylling, Manager of Cardiac Cath, Special Procedures, Scott.Fylling@bhsnet.org We still do weekly Kv and Ma readings in all our rooms and look for any variance of > 10% up or down. We have not been flashing a standard 3MM cooper plate daily as we did in the past with film to verify optical density. Possibly we could use a line pair phantom each day or week to verify any changes in video or digital capture processing at the cineless view stations. Do we know of any standards set by DICOM, the different states or OSHPAD? Bill Colditz, RCIS, Manager Cath Lab Mercy San Juan Medical Center Wcolditz@chw.edu We do daily QA checks using the 3MM copper plate to determine dose changes using MA and pulse width. We also have a permanent record of the fluoro time and cine frames/sec for the patient in case we need to figure out exposure levels. Our physicist will perform safety/quality checks twice a year on equipment. Roberta Sparks, RN, RT(R), RCIS, Coordinator Good Samaritan Hospital Downers Grove, IL Roberta.Sparks@advocatehealth.com This is a great question! We became cineless in August 2001, and have not done daily QC since, though we have had the same question about what we should be doing.On our old room, we knew the doses for fluoro and cine on each II mode and any case that went beyond 40 minutes of fluoro time went to our physicist and radiation safety officer for review and tracking. We send a monthly dose report to our Radiation Safety Office that includes patient ID information, fluoro time and dose (Gycm2). I will be anxious to hear what others are doing. Natalie D. Beiler, BSN, RCIS Rockingham Memorial Hospital Harrisonburg, VA NBeiler@rhcc.com Natalie (above): We are in the same boat. So far, no one has given any indication of how daily QAs are being done on filmless systems. All of our systems are checked by a physicist once a year. All were out of variances this year because there is no easy method of QA-ing the equipment. Chuck Williams, Codywms@msn.com Regarding quality control in interventional labs: 1. The installer should have given you a quality control protocol. That’s worth $999,999.00 of the installation. The rest only costs $1.00. If they didn’t, then they should have recommended one. If they do not meet your needs, tell them to get off their duff or you’ll report them to an appropriate regulatory agency. 2. Cineless labs are usually full digital in other respects. Data stored for American College of Cardiology or other use may include the fluoro-time, patient dosimetery, etc., and thereby handle quality reporting as well as patient outcomes. Jackson Thatcher, MD, Director, CCU and Acute Myocardial Infarction Care Improvement Initiative and Registry Chair, Formulatory Committee, The Park Nicollet Heart Center at Methodist Hospital, St. Louis Park, MN Dr. Thatcher (above): Some folks feel that the systems are foolproof and only need to be checked once a year for radiation doses as specified by the state regulatory division. I am trying to find a method that technologists can do on a daily basis that can indicate that an automatic brightness control drift has occurred and/or an automatic gain control has drifted. This involves cineless systems. The manufacturers have electronic protocols with which they set up our flat panel system, except our most recent lab could exceed 10R/min during fluoroscopy. The field engineer who was the final installation person was amazed when he saw the readings appear. The mA/mR was above limits also. Chuck Williams, Codywms@msn.com Would you like to add to this discussion? Email us at: cathlabdigest@hotmail.com Next month: We publish the results of our Scrubbing Attire poll.
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