Letters to the Editor
It is not rare that venipunctures are repeated several times when appropriate veins cannot be found, and that may worsen the patient’s quality of life in the hospital. Dilating the target vein topically is an important method of aid to venipuncture. Nitroglycerin (TNG) vasodilating properties have helped venipuncture by the use of TNG ointment (1, 2). However, the application of TNG for this purpose may not be suitable for patients without ischemic heart disease because of complications such as headaches. The simple alternative application method of applying TNG tape over a venipuncture site instead of the chest may be a more effective application. We investigated whether a TNG tape would work as an aid to venipuncture for the patients who used the TNG tape as part of their heart disease treatment.
We studied 57 patients, who were suffering from ischemic heart disease and TNG tape users. A TNG tape containing 5 mg of in 5 cm × 10 cm TNG (Millisrol® tape; Nippon Kayaku Co., Tokyo, Japan) was applied over the back of one hand instead of the chest in the TNG group (n = 32); a placebo was applied over the back of one hand in addition to usual application of a TNG tape on the chest in the placebo group (n = 25). The grade of vein dilation at the hand was estimated by using 4-point visual grading score (Grade 1, the veins can be hardly found; Grade 2, the veins can be barely found; Grade 3, the veins look clear; Grade 4, the veins are overswelling, at clenching the hands in the supine position) 60 min after the application. The TNG tape was removed and reapplied on the chest just before the estimation in the TNG group. The score after the application of a TNG tape was significantly greater than before the application (P < 0.01 by Wilcoxon’s test). However, the score of the placebo did not change significantly. No patient had an angina attack.
If venipuncture is needed in patients who frequently use a TNG tape, we would like to recommend that a TNG tape be applied over a venipuncture site instead of the chest and removed from the site and reapplied on the chest to maintain the therapeutic effect of TNG just before venipuncture.
Satoki Inoue Hideo Ninaga
1. Lohmann M, Moller P, Brynitz S, Bjerrum OW. Nitroglycerin ointment as aid to venipuncture. Lancet 1984; 1:1416–7.
2. Hecker JF, Lewis GB, Stanley H. Nitroglycerine ointment as an aid to venipuncture. Lancet 1983; 1:332–3.