IV. Effectiveness of Sterilization: Hysteroscopic versus Laparoscopic/ Minilaparotomy

Laparoscopy gained wide spread acceptance in the United States in the early 1970’s. By 1973 more sterilization operations were performed for women than for men due to the dramatic decrease in cost, hospital time and pain after the introduction of laparoscopy and minilaparotomy methods. The use of laparoscopy for tubal occlusion increased from only 0.6% of sterilizations in 1970 to more then 35% in 1975. 13 Laparoscopic and minilaparotomy sterilizations were not only convenient but also highly effective methods of preventing pregnancy and replaced the older, complex procedures. Hospitalization is not required, most patients return home within a few hours, and the majority of women return to full activity within a few days. The discomfort is minimal, the incision scars barely visible and sexual activity need not be restricted. In addition, the surgeon has the opportunity to inspect pelvic and abdominal organs for abnormalities. However the disadvantages of laparoscopic sterilization include: the cost, the expensive and fragile equipment, special training requirements, risk of inadvertent bowel and vessel injury, and the need for general anesthesia (in most instances). It is now apparent that the long term failure rates for all methods of laparoscopic sterilization are higher than previous estimates. Overall 1.85% of sterilized American women experience a failure within 10 years. 11-12 As much as one third of these failures are ectopic pregnancies. In 2002, in the United States female sterilization was used by 10.3 million women and was second only to oral contraceptive users of 11.6 million women. 14 Although female sterilization by laparoscopy/minilaparotomy is effective it is associated with significant risks of major complications. As published by Jamieson et al., tubal sterilization performed via laparoscopy is associated with a 1.6% major complication rate, and Layde et al, reported 5.7% major complication rate when tubal sterilization is performed via laparotomy. 15-16 Additionally, performing laparoscopy for sterilization under local anesthesia increased the risk of complications five-fold as reported by Destefano et al. 17 The vast majority of the major complications through laparoscopy/ minilaparotomy are created by the incision, blind insertion of laparoscopic instruments and the use of general anesthesia. It was only a question of time until improvements in female sterilization came about as it affects such a huge proportion of women.

In a direct comparison to the CREST study data at five years, the Essure procedure presents a favorable risk profile over the majority of tubal sterilization methods, as evidenced in the table below.

Comparison of cumulative risk of pregnancy in the CREST study vs. Essure sterilization*

The Essure Procedure does not require cutting or penetrating the abdomen. It can be performed without general anesthesia in an outpatient/office setting. This major advantage of the hysteroscopic technique of sterilization has firmly placed the Essure procedure as a contender for first choice for female permanent contraception. A disadvantage of the procedure is the need for alternate contraception three months after the procedure, as is not effective immediately. A perceived disadvantage is the required HSG at three months post-procedure. However, no method of contraception is 100% effective, the HSG provides the patient and the physician assurance that the method is working. In addition, if there is an issue, it can be identified at the time of HSG and appropriate action can be taken.

V. Indications and Contraindications of the Essure Procedure

The Essure procedure is indicated for women who desire permanent birth control by bilateral occlusion of the fallopian tubes.

The Essure procedure should not be performed in the following patients:

• A person who is uncertain about permanent sterilization
• When bilateral tubal micro-insert placement cannot be performed due to uncertainty of the status of the contralateral tube; ie. where either partial or total salpingectomy has been performed in the past or where pathological conditions of the tube may exist
• When both tubes have already had tubal occlusion performed by another method
• Known allergy to contrast media
• Known hypersensitivity to nickel confirmed by skin test

The Essure procedure should be delayed in the following patients

• When question of pregnancy or suspected pregnancy may be present
• When a birth or pregnancy termination has occurred less than six weeks prior
• In the presence of active or recent pelvic or lower genital tract infection 

VI. The Essure System: Description of Product

The Essure permanent birth control system consists of the Essure micro-insert, a disposable delivery system, and a disposable split introducer. A standard hysteroscope with a 5 French working channel, a continuous flow, and a 12-30 degree angled lens is used in concert with the system. The 5mm hysteroscopes made by Karl Storz Endoscopy and Richard Wolf Medical Instruments both accommodate the Essure system.

 

The Micro-insert

This consists of a stainless steal inner coil, a nitinol super elastic outer coil, and PET fibers. PET fibers are used in other medical application such as prosthetic arterial graphs, percutaneous catheters, aneurysm coils and other long term implants. The PET fiber is wound in and around the inner coil. The micro-insert is 4cm long and 0.8mm in diameter in its wound down configuration. When released the outer coil expands to 1.5-2.0mm. This anchors the micro-insert inside the tube.

The Disposable Delivery System

This consists of an ergonomic handle which contains a delivery wire, release catheter, and delivery catheter. The ergonomic handle controls the delivery and release. A thumb wheel on the handle allows the operator to retract both the delivery catheter and release catheter. The delivery wire is detached from the micro-insert on deployment by rotating the system in a counter-clockwise direction.

Split Introducer

This helps protect the micro-insert as it passes through the sealing cap of the hysteroscopic working channel.

Mechanism of Action

The Essure micro-insert remains anchored in the fallopian tube resulting in permanent contraception because it is small enough in diameter to be placed across, and long enough to span, the uterotubal junction. This specific portion of anatomy was chosen for placement of the micro-insert to prevent the expulsion of the device during menstrual uterine contractions and it is the narrowest portion of the tube. Yet, the device is long enough in its proximal portion to allow coils to trail inside the uterine cavity (specifically 3-8 coils). This trailing portion in the uterine cavity aids in anchoring. The expanded outer coils within the uterus are almost twice the diameter of the expanded coils within the tube. This greater outer diameter of the expanded coils initially anchors the micro-insert preventing the migration of the device into the peritoneal cavity.

Stages of Micro-insert Deployment

The PET fibers then begin to elicit the fibrotic response. The long term nature of the tissue response is not known. The majority of the clinical data at the end of 5 years of use suggest permanence of fibrotic response.

Histological response to PET fibers

VII. Procedure Description and Pre/Post-procedure Protocol

Pre-procedure Protocol 18:

Standard pre-procedure consent for sterilization must be obtained as required by local laws. The physician should be trained in hysteroscopy and the Essure procedure and should have been proctored for at least five cases or as required by the hospital credentialing committee. Similarly the operating room nurses and staff should be familiar with the instrumentation. The anesthesiologist should be supportive of the patient during the procedure under local anesthesia and/or with any IV sedation, as required. Before the procedure reconfirmation of consent must be performed by the circulating nurse, especially emphasizing the fact that the Essure procedure is an irreversible, permanent contraception technique. It is preferable to perform the procedure in the early proliferative phase to avoid placement during an undiagnosed luteal phase pregnancy. Additionally, this enhances the visualization of the fallopian tube ostia. Micro-insert placement should not be performed during menses.

A pregnancy test should be conducted 24 hours prior to the micro-insert placement. The patient must be informed that there is a 12%-14% chance that a bilateral placement would be unsuccessful during the first attempt due to pre-existing pathology, anatomic abnormalities, or procedure related difficulties like poor visualization of the tube. 19 However, bilateral placement may be completed during the second attempt.

Pre-op Medications

Injection Toradol 30mg IM or IV should be given half an hour prior to the procedure to prevent tubal spasm. An anxiolytic agent may be given half an hour before as preferred by the anesthesiologist

The Procedure

The patient is placed in the lithotomy position and is draped per standard protocol, and an under buttocks drape with a pouch for fluid collection is recommended. Ski boot style stirrups are recommended. If the fallopian tubes are laterally situated the patient’s legs may need to be widened to allow hysteroscopic access. Next the speculum is introduced into the vagina to expose the cervix. The cervix is prepped with betadine then a local anesthetic is given as a paracervical block. A bi-valve open-sided speculum is recommended so that it can be readily removed once the hysteroscope is in place. It is important to inform the patient before administering the local anesthetic injection to reduce pain and discomfort. Soothing words may help to minimize the discomfort. The circulating nurse is an important adjunct to this process. The paracervical block takes about 3-4 minutes. This time may be utilized to connect the camera, light source, sealing cap, fluid in flow and out flow to the hysteroscope. The hysteroscope may be balanced and focused, and in-flow may be checked. Then tenaculum is placed on the anterior lip of the cervix. The hysteroscope is introduced without dilation of the cervix through the external os, here the patient may be invited to view the procedure on the monitor while the anatomy is being described. The irrigation is turned on using normal saline through a fluid management system which may be in use in the hospital setting or the fluid may be introduced by gravity. If excessive force is required to enter the cervix it is better to terminate the procedure then run the risk of uterine perforation. Other measures pre-operatively may be utilized in the future to achieve cervical dilation of a stenotic cervix (ie. laminaria, misoprostol, or vaginal suppository).

It is important to maintain visual and verbal contact with the patient during the potentially uncomfortable segment. If cervical dilation is required, dilate only sufficiently to insert a 5mm hysteroscope. After the hysteroscope negotiates the cervix remove the speculum. Uterine cavity distention is achieved with 0.9% saline infusion. It is strongly recommended to pre-warm the infusion fluid to prevent tubal spasm. Adequate uterine distention must be achieved and maintained throughout the procedure to allow the identification and access of the tubal ostia. Fluid intake and out-flow must be accounted for per standard protocol. If the fluid deficit exceeds 1500cc the procedure must be terminated to avoid hypervolemia.

Both tubal ostia must be identified and assessed hysteroscopically prior to proceeding with Essure micro-insert placement. No attempt should be made to place a micro-insert in one tubal ostium unless there is a reasonable expectation that the opposite tubal ostium is accessible and patent. If there is a doubt about successful bilateral placement then the procedure should be terminated. Either tubal or uterine anomalies may make it impossible to place the Essure micro-insert. It is recommended that the system remain within the sterile packaging until both ostia are visualized. It is important to assess the actual system for any damage. Next, insert the split introducer with the opening face up through the sealing cap of the working channel of the hysteroscope. Insert the Essure delivery catheter through the introducer after removing the stylet of the split introducer. Now the Essure delivery catheter is advanced half way down the hysteroscope working channel when the split introducer is removed. The hysteroscope is rotated as required to access the ostium using the light cable attachment while the camera head is kept steady. Angling the lens 12-30 degrees will aid in aligning the hysteroscope with the tubal ostia. Now the catheter is advanced into the fallopian tube until the black positioning marker can be visualized as having reached the ostium.

This visual marker indicates that the micro-insert is spanning the intramural and proximal isthmic segments of the fallopian tube with the outercoil spanning the uterotubal junction. This positioning is for the placement of the micro-insert. Occasionally, it is necessary to exert gentle forward pressure to advance the catheter into the tube to overcome tubal resistance. Resistance to advancement is usually apparent if 1) the black positioning marker on the outside surface of the catheter does not advance forward to the tubal ostia and/or 2) the delivery catheter bends or flexes excessively preventing the application of forward pressure on the catheter. When such resistance is observed further attempts for advancement must be terminated to avoid uterine or tubal perforation. A follow-up HSG may be undertaken to determine tubal patency. If tubal or uterine perforation occurs or is suspected, immediately discontinue the Essure procedure. If tubal obstruction is encountered or if the delivery catheter cannot be advanced to the black positioning marker then the case should be terminated.

After confirming proper positioning of the black marker the micro-insert can be deployed. To do so, stabilize the handle of the Essure micro-insert against the hysteroscope or the camera to prevent inadvertent forward movement of the micro-insert during the retraction of the delivery catheter. Care must be taken at all times to not to bend the delivery catheter outside of the hysteroscope which may result in the unwanted movement of the distal tip of the catheter. Now the thumb wheel on the ergonomic handle is rotated toward the physician to withdraw the delivery catheter. The thumb wheel rotation should be performed at the rate of one click per second until the wheel stops. The black positioning marker will move away from the tubal ostium towards the hysteroscope and will disappear in the hysteroscope operating channel. Withdrawal of the delivery catheter exposes the wound down Essure micro-insert attached to the orange release catheter. Approximately one centimeter of the micro-insert wound down coils should appear trailing into the uterus when the delivery catheter is withdrawn.

Placement: Spanning the uterotubal junction

A small notch identifies this aspect of the micro-insert – the notch appears where there is a slight increase in the diameter of the coils. The visualization outside the notch just outside the ostium, as well as, the visualization of the distal tip of the orange release catheter will confirm proper positioning. Forward and backward movements of the entire system may be gently performed to achieve perfect placement. After retracting the delivery catheter and confirming the proper positioning the deployment button on the ergonomic handle is depressed to enable the thumb wheel to be further rotated. Now rotate the thumb wheel backwards towards the physician to withdraw the orange release catheter while continuing to stabilize the handle. When the thumb wheel cannot be rotated any further then the withdrawal of the orange release catheter is complete. This enables the outer coil of the Essure micro-insert to expand which is easily visible to the operator. Allow ten seconds for the outer coil expansion while aligning the hysteroscope and the delivery system to minimize the bending of the catheter. The entire delivery system should be carefully straightened out prior to the next step which is the counter clockwise rotation of the ergonomic handle. This rotation allows the delivery wire to become visibly disengaged from the Essure micro-insert. Ten such rotations are usually required to allow disengagement. While continuing the rotation to remove the delivery wire, the delivery system may be gently drawn from the micro-insert by pulling the handle backwards. If there is difficulty in separation of the micro-insert from the delivery wire then the hysteroscope tip may be used to accomplish this step as a last resort. In a majority of instances counter-clockwise rotation and application of gentle backward tension on the handle is able to achieve successful detachment of the delivery wire from the micro-insert. To verify the separation, obtain a panoramic view by sliding the hysteroscope backwards over the delivery wire. For trouble shooting Essure system retraction appropriate training with a clinical specialist is recommended. It is encouraging that the learning curve is very short for these procedures. If none of these techniques are successful the deployed micro-insert can be pulled out of the fallopian tube by continuous backward movement of the delivery system and removing the hysteroscope and the Essure system out of the patient as a unit. If the micro-insert is partly broken, the patient must be instructed not to rely on this for contraception and if the broken micro-insert is causing an adverse event an attempt must be made to remove it.

The ideal number of expanded outer coils trailing within the uterine cavity is 3-8 coils. If the number of outer coils is less than eighteen the micro-insert should be left in place and evaluated with an HSG three months post device placement. Removal may be attempted if eighteen or more coils are trailing into the uterine cavity. The physician must refer to company sponsored instructions on how to attempt removal of micro-insert. There is a likelihood of fallopian tube perforation or other patient injury if such instructions are not adhered to. If the micro-insert is inadvertently deployed into the uterine cavity it should be removed from the uterus and another attempt should be made at tubal placement. Repeat the Essure micro-insert placement procedure in the contralateral fallopian tube. Do not place more than one micro-insert in a single fallopian tube.

 

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October 2006

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