|Cardiac Cath 5/6|
The Cardiac Cath learning module is made up of 6 parts or sections. You may navigate through the pages by clicking on the green arrows or numbers (above), the specific questions (below) or the gray menu items on the left.
What is Cardiac Catheterization?
The x-ray camera sits on top of the patient's chest, while the x-ray beam is
delivered from underneath the table. A movie camera is attached to the tube to
record images on a 35mm film. Images are also noted "live" on the monitor and
are also recorded on a computer disk drive and / or a video tape. The x-ray tube
is rotated around the patient (side-to-side, and also towards and away from the
head), as shown below. By taking pictures from different angles, the
cardiologist can inspect blockages from several points of view. This increases
the accuracy of assessing the clinical importance and severity of a blockage. It
also helps determine the patient's candidacy for angioplasty, stenting, surgery,
medical treatment, etc.
The patient may have a feeling similar to a bee sting when the groin is "numbed" with local anesthesia. A sticking sensation is also felt when the needle is inserted. This is very tolerable. The cardiologist should be notified if there is a lot of discomfort or pain. Additional local anesthesia or more sedatives will usually alleviate the discomfort.
The patient will be lying on a relatively firm table and the room will be cool. During the procedure, the patient may be asked to hold his / her breath or cough. The former improves the quality of the x-ray movies when the diaphragm (muscle partition between the chest and abdomen) partially obscures a certain portion of the coronary artery. A deep breath improves the picture.
The contrast material may occasionally cause the heart to slow down. Coughing helps clear the contrast from the coronary artery. Coughing may also help correct certain types of abnormal heart rhythm.
The patient should be able to watch most of the study on the TV monitor. The cardiologist may explain the findings as the procedure is carried out.
It is important to remember that the blue or green sheets covering the patient are sterile. Hands should be kept by the side and not placed on top of the sheet. The patient should not reach for the groin because it will contaminate the catheter. If a pillow needs to be rearranged or a cheek scratched, the staff will be happy to help.
Fleeting chest discomfort may also be felt during some coronary artery injections. A transient "hot flash" is usually felt when pictures of the Left Ventricle (LV) are taken, as shown below. This sensation generally clears up in less than 30 seconds.
Angiogram of the Left Ventricle
The coronary arteries are relatively small and can be easily filled by injecting around 5 to 8 cc or ml of contrast or "dye" , with the help of a hand-held syringe. X-ray movies are usually taken when the arteries are filled with contrast. The left ventricle (LV or the major pumping chamber of the heart), on the other hand, is larger and requires more contrast to fill it. To allow proper visualization of the LV, nearly 30 or more cc of contrast is injected over 2 to 3 seconds with the use of a power injector.
The x-ray pictures are taken by a movie camera. It will sound like a hum, motor or loud sewing machine when pictures are being recorded.
Pulling the Sheath from the Artery
Removal of the sheath and application of pressure in the area, to prevent bleeding, is shown above. A dressing is then placed on the groin and a sand bag or ice bag may be used on top of the dressing. The patient will have to lie flat for three to four hours. It is important to not sit-up, bend the leg or strain during the time of bed rest. However, the head of the bed may be raised slightly and the feet can be moved to a small degree. Removal of the sheath is delayed if heparin or other "blood thinners" are used during the procedure. The sheath is pulled when a blood test indicates that it is safe to do so.
If there is a warm or wet sensation around the catheter insertion site or if there is blood on the dressing, pressure needs to be applied at the site and the nurse called immediately. If there is bleeding, there is no need for panic. Additional pressure will almost always take care of the problem.
If there is a need to sneeze or cough, light finger pressure must be applied right above the catheter insertion point. A nurse will provide instructions. This will reduce the risk of bleeding.
If the arm is used during the procedure, pressure will be applied over the insertion point.
Some cardiac centers use closure devices in the cath lab. In such cases, the hole is sealed when the patient leaves the lab and application of pressure is not usually needed. This increases the cost of the procedure and carries a very small and acceptable complication rate.
When the anesthesia wears off, the patient may experience soreness. The nurse can provide pain medication to take care of this problem. The blood pressure and pulse rate are monitored during the recovery phase.
The nurse needs to be notified if there are any problems with dizziness, lightheadedness or chest discomfort. Nausea may occasionally occur and is usually resolved with medications. The contrast material acts as a diuretic or "water pill." Also, a lot of intravenous fluids are used. This combination will cause the patient to produce large amounts of urine. Some patients may not be able to void in the flat or supine position. If the bladder gets distended and causes discomfort, a tube may be temporarily placed in the bladder.
After bed rest is completed, the patient is made to sit up and then stand with assistance. After further observation, if there are no problems or bleeding, the patient is discharged
|Cardiac Cath 5/6|