Cleveland Family Study

10.15 Nitroglycerin

The NTG portion of the procedure will not be performed until the image quality and the timing of the reactive hyperemia portion of the procedure are adequate. If inadequate, the reactive hyperemia portion of the procedure will be repeated after a 15-minute rest. If adequate, the NTG portion will be performed. One NTG is administered, the patient’s artery will not return to its resting diameter for 30 minutes. NTG should not be given to individuals with systolic blood pressure ≤ 90 mmHg.

1. The patient will rest for 15 minutes to allow the artery to return to its resting diameter.
2. The screen annotation will be changed to “UA NTG BL.”
3. The patient will be handed a bottle cap containing a 0.4mg NTG tablet to ensure that the tablet will not be dropped and does not start to dissolve between the patient’s fingers.
4. When instructed to take the NTG, the patient will indicate the tablet is under his/her tongue.
5. The S-VHS VCR record function will be activated.
6. A new baseline 2-D image and PW Doppler will be acquired utilizing the same methods and criteria previously described.
7. The scanhead will be placed on top of the magic marker outline to utilize the same acoustic window that was used for the reactive hyperemia portion of the procedure.
8. The annotation will be changed to “UA NTG” and the patient will be instructed to place the NTG tablet under his/her tongue.
9. “NTG” will be typed on the screen along with the exact time to the second.
10. This time will be recorded on the Site Worksheet.
11. The artery will be continuously imaged in the zoom mode. As time passes, the artery will significantly dilate.
12. At 5 minutes post administration of NTG, an image will be obtained.
13. At 5 minutes and 15 seconds post NTG the last PW Doppler will be acquired.
14. 2-D image acquisition will be recorded until 6 minutes post NTG administration.
15. Once the videocassette tape has been ejected from the VCR, the ultrasonographer will remove the plastic record tab from the left end of the spine of the tape to prevent accidental erasure of the procedure.
16. The patient will be encouraged to sit on the edge of the stretcher before standing after the NTG portion of the procedure to prevent lightheadedness.
17. If using an automated sphygmomanometer the datascope BP strip will be attached to the worksheet.