Hysteroscopic Myomectomy Safe and Easy

As a general rule of thumb, monopolar systems using nonelectrolyte solutions must be stopped earlier to avoid hyponatremia.

There are variations in practice, particularly among gynecologists with significant hysteroscopy experience, but experts typically recommend a threshold of no more than 1,000 cc for monopolar systems, and a threshold of no more than 2,000 cc when electrolyte solutions are used with a bipolar system.

Particularly with larger fibroids, which require more time and more fluid, consider injecting dilute vasopressin into the cervical stroma at the start of the surgery. Several studies have shown that vasopressin reduces intravasation of the fluid, makes the cervix easier to dilate, and decreases intraoperative bleeding.

Surgical Technique

Some surgeons prefer to insert the hysteroscope into the cervix blindly, whereas many prefer to advance it under direct visualization. Some prefer mono- or bipolar scopes with a 12-degree angle, whereas others like to work with 25- or 30-degree hysteroscopes. The Smith & Nephew system uses a 0-degree scope.

There are, however, some givens. With any system, a fibroid should never be removed at its base because a free-floating fibroid is difficult to retrieve. Each fibroid should be shaved down in strips, the number of which depends largely on the size of the loop (if the monopolar or bipolar hysteroscope is being used) and the percentage of fibroid that is in the cavity.

When using the monopolar and bipolar hysteroscopes, place the loop in contact with the fibroid and then apply a minimal amount of tension going back toward the cervix before activating the electrode. Do not activate the electrode until you have the loop coming back toward the cervix.

This process must be deliberate and precise, because once the loop is activated, there is little tactile sensation. Then shave the fibroid down in strips until the myometrium is reached. With the morcellator, the rotary blade must run in contact with the fibroid.

At that point, intentionally let the endocavity deflate and the myometrium decompress. Quite often, you will find that the intramural portion of the fibroid now protrudes into the cavity, having been pushed outward as a result of the myometrial decompression and the decrease in endocavity pressure. It can then be shaved down more.

If you can see the pseudocapsule between the muscle and fibroid, you can also then use your wire loop to “massage out” any remaining portion of the fibroid. Often, if the maximum fluid absorption has not been reached, you will be able to massage it out, shave it down, massage it out more, and so forth, to the extent that you can actually resect the deep intramural portion of the myoma. If you cannot see the pseudocapsule, it is time to stop the surgery.

Some surgeons may opt at this point to proceed laparoscopically to retrieve the remaining intramural portion of the fibroid, particularly if they estimate that more than 10%–15% of the fibroid remains, and if they are operating on patients with infertility concerns or patients who are planning to undergo in-vitro fertilization. Or they may chose to come back later for a repeat procedure.

Other surgeons prefer a less aggressive approach—in which the patient's symptoms are monitored, and she returns to the office in 2–3 weeks for a flexible diagnostic hysteroscopy—particularly when dealing with patients whose symptoms do not include infertility. More often than not, any remaining portion of the fibroid will appear white and avascular and will not cause any further trouble for the patient.

The bottom line, regardless, is that hysteroscopic surgery is successful if the presenting problem is safely eradicated. Your level of aggressiveness will be determined largely by your patient's symptoms and individual situation. With a careful preoperative evaluation of the fibroids and the use of sound judgment early on about the appropriateness of the procedure and your own skills, repeat procedures will and should be unusual.

The Nuances of Intrauterine Pressure

Remember that as uterine distention pressure rises higher than the mean arterial or venous pressure, fluid absorption also rises. There is an advantage, therefore, to maintaining the lowest intrauterine pressure possible; also, more of the fibroid will protrude into the cavity. On the other hand, the greater visibility gained with greater distention makes it advantageous to work under higher pressures.

Some surgeons work at 100 mm of pressure consistently and believe they can work quickly because they can see well; others start surgery at 50–60 mm of pressure and gradually increase the pressure to achieve greater distention and visibility as needed.