New Patient Placement Creates Safer Catheterizations for Morbidly Obese Patients

As America’s waistlines grow, there is an escalating rate of cardiac disease. With it comes the ever-increasing problem as to how to perform standard cardiac catheterizations on these patients. In Pennsylvania alone, 27.1% of the population was found to have a body mass index (BMI) greater than 30, according to a 2007 Centers for Disease Control and Prevention (CDC) survey.¹ The difficulty in performing these procedures arises from the percentage of patients who are morbidly obese and exceed standard weight limits on catheterization tables. At Geisinger Medical Center in Danville, Pennsylvania, the highest current weight recommended by the equipment is 220 kg (485 lbs). The current method of patient placement on the procedure table creates a less efficient and safe method for the evaluation for coronary artery disease. Placing a patient larger than the recommended weight limit of the table makes for a dangerous environment for both the patient and the staff of the lab. The first problem involves the act of moving the patient from their stretcher to the cath table. Many morbidly obese patients have a difficult time moving themselves while lying on their backs. This means the staff has the task of moving the patient from the litter to the cath table, risking injury. The second major problem that is encountered is the size of the patient. Cath tables are built for efficiency rather than comfort, some measuring as little as 18 inches in width. These tables have no way to accommodate the larger widths, creating a greater than average risk of falling off the table, as well as decreased comfort for the mobidly obese patient. Panning a table with patients of this size becomes increasingly difficult for staff. There is also an increase in radiation exposure to both the patient and staff. It is hard to utilize the additional shielding that comes with the x-ray equipment when maneuvering it is hindered by the positioning of the patient on the table. The last and most life-threatening problem with catheterizing morbidly obese patients is if the need for CPR arises. The cath table is already under an additional strain. Add the force applied to the table during CPR and there is a great chance that the unsupported table will break or at least incur some damage. In order to help support the table for CPR, a scrub table or a series of sawhorses should be placed under the cath table where it has no base. These can help to support the cath table during CPR, but this solution is highly impractical since it causes a delay in performing life-saving measures. We have devised a new patient placement system where patients can be safely catheterized regardless of their weight through a radial approach. Using the following steps for setup, the risks in cathing these larger patients can be minimized. 1. Place patient on a stretcher instead of a hospital bed. 2. Wheel the stretcher to the left side of the cath table. The head of the stretcher should be at the shoulder area of the cath table so they are facing perpendicular to each other. 3. Ensure both beds are locked and attach a support board under the x-ray table mattress and under the top of the stretcher mattress. This helps the beds to move together and support the patient. 4. The patient then moves themselves, with help of the staff if necessary, north towards their head, so that they reside half on the cath table and half on the stretcher. This allows the arm to fall at the center of the cath table (see Figure 1). 5. Place a pillow under the patient’s head and extend their arm 90 degrees outward so that the wrist falls approximately where the groin would normally be on the cath table. 6. Use sterile drapes to cover both the patient and the wrist to be used for access. There are a few things to keep in mind when performing this special procedure. Extra staff will be required since personnel will be needed to help move the stretcher during panning. The smoothest way to communicate during panning is to use directional commands (i.e. north, south, east, and west) to make sure both the physician and the driver of the stretcher can see the image so you can pan the path of the coronaries (see Figure 2). If possible, rotate the image intensifier one quarter turn so the images appear on the screen as they do in a normal cath. If you can not rotate the image intensifier, you will still obtain a good image, just rotated. With the position that the patient is lying on the table, the camera angles will be different. RAO cranial will become LAO cranial; RAO caudal will become RAO cranial, and so on. In our experience with using this procedure, patients and staff were exposed to less radiation and both were more comfortable. It allowed for better access and support of the patient in the event of CPR. This makes it possible to increase our maximum patient weight from 220kg to 440kg (970lbs). Yet despite the increased size of the patient, the procedure was just as easy and effective as the majority of outpatients. With this modified method of patient placement on the procedure table, patients can safely and more effectively be evaluated for coronary artery disease. The authors can be contacted via Elizabeth Truxall at eetruxall@geisinger.edu

1. Centers for Disease Control and Prevention. U.S. Obesity Trends 1985–2007. Available at http://www.cdc.gov/nccdphp/dnpa/obesity/trend/maps/index.htm. Accessed January 19, 2010.