Endometrial Biopsy Using Intrauterine Lidocaine Plus Naproxen Sodium

Abstract and Commentary

Synopsis: Endometrial biopsies were performed using intrauterine lidocaine only, naproxen only, both, or neither. Intrauterine lidocaine significantly reduced the pain when used in conjunction with oral naproxen sodium.

Source: Dogan E, et al. Obstet Gynecol. 2004;103: 347-351.

In this randomized, double-blind, placebo-controlled trial, patients undergoing Pipelle endometrial biopsy were assigned to one of 4 groups of 30 patients each. All patients received an intrauterine installation of either 5 mL of 2% lidocaine or sterile saline by way of 18-gauge catheter, and either 550 mg naproxen sodium or placebo by mouth. The catheter was left in place for 3 minutes to minimize loss of fluid. Each Pipelle sampling was performed using a minimum of 3 passes. Pain was rated by both patient and physician.

Although the pain reported by the patients in the naproxen-only and lidocaine-only groups were 18% and 17%, respectively, less than the placebo group, these figures were not statistically significant. Similarly, when both active drugs were used, they were not statistically better than either drug alone, but the combination was significantly better than placebo. The same findings were reported in the sub-group of postmenopausal patients. The physician-reported scores also showed significant benefit for the combination.

Comment by Frank W. Ling, MD

This is a beautifully designed study, presenting Level I evidence at its best. Endometrial sampling using the Pipelle or similar instrument is a very common procedure in the gynecologist’s everyday office practice. When patients can be made more comfortable, each of us needs to look carefully at how it could positively affect our own practice style. Admittedly, the amount of discomfort is related to your own "pre-operative" technique. I have personally observed a lot of residents in training perform such a biopsy with varying results. Often it relates as much to the interpersonal contact that is maintained with the patient as it is the manual technique that is used. This is entirely separate from the issue of using oral non-steroidals, intrauterine installation of lidocaine, or both.

Merely telling the patient what you are doing before doing it makes a huge difference. It is the same principle as is taught when a pelvic examination is done. "Talk, then touch." If the patient knows what is going to be done before it is, she is that much better able to tolerate it because it is no longer a surprise or unexpected. Dogan and colleagues don’t say how much of that "verbal anesthesia" is used in the study, but each of us should recognize that the reassurance and comfort that a patient derives from us telling her what we are doing is not inconsequential.

Dogan et al are correct in pointing out that a tenaculum on the cervix is not mandatory in all cases. I am confident that each of us tests each patient to see if we can get by without using it. If I find that it is necessary, I use the distraction technique to apply it initially, ie, I ask the patient to cough a couple of times as I close the tenaculum to the first notch. That will help bring about some reduction in the initial pain perception, then I will tell the patient that I am going to close the instrument a little more (I don’t use the word "clamp"), which might cause some more discomfort (I don’t use the word "pain").

Passing the Pipelle is often quite easy, but sometimes obstruction is met. I typically perform a bimanual examination beforehand to determine if the uterus is anteverted/retroverted and anteflexed/retroflexed to aid my "aiming" of the Pipelle. I do not sound the uterus, since I believe that the bimanual tells me how large the cavity is approximately, and also that the use of a uterine sound is an invitation to causing a perforation. The one exception that will cause me to use a sound is when the Pipelle will not pass initially, then it won’t even pass when I grasp it with a ring forceps in an attempt to guide it into the cavity.

There are a couple of other techniques which may prove beneficial occasionally, both of particular value if a patient has a relatively stenotic cervical os. I hear people talk bout lacrimal duct probes being helpful, but I personally find the wooden end of a small cotton swab to be of equal or greater utility. Also, as a last ditch effort to avoid taking a patient to the operating room with its risks and costs: try a #11 blade to open the dimple which is the remnant of the os. Pushing it in slightly, then removing it and rotating it 90° for another incision creates an entry into the endocervical canal.

So in the routine of our daily practices, perhaps the use of lidocaine with oral naproxen sodium should be considered for our Pipelle biopsies. Certainly endometrial-sampling techniques should be scrutinized just as any other aspect of our practice. If we make our patient’s experience better, then we should go for it.

Frank W. Ling, MD, Professor, Dept. of Obstetrics & Gynecology, University of Tennessee, Health Science Center, Memphis, TN, is Associate Editor for OB/GYN Clinical Alert.