Cervical Incompetence 2

MANAGEMENT OF CERVICAL INCOMPETENCE INTRODUCTION

HISTORY: - mostly retrospective - mid-trimester abortions - pre-term labour - uterine malformations - in-utero use diethystilbesterol - vaginal deliveries – repeated vaginal deliveries, high parity, precipitate labour, operative vaginal deliveries with injuries to the cervis, prolonged vaginal deliveries due to mechanical difficulties as in delivery of macrosomic babies. - Excessive or forceful dilatation of the cervix. - Amputation of the cervix - Cone biopsy

PHYSICAL EXAMINATION/INVESTIGATIONS IN NON-PREGNANT STATE - Ease of passage of size 8 Hager dilator - Foley traction test - HSG – dilated internal os and widened isthmus. Usefulness of these tests are doubtful. Evidence of torn cervix are more useful in the diagnosis.

IN PREGNANCY High index of suspicion. In cases in which the patient had a previous mid-trimester abortion or early third trimester but without the classic history – serial digital cervical examination. Accidental discovery of effacing cervix during routine vaginal examination. Ultrasound scan – more accurate than serial digital examinations. - length of the cervix. - Width of the cervix. - Dilatation of the internal os and endocervical canal. - And response of these parameters to stress such as a transfundal pressure, coughing or standing are all useful in confirming the diagnosis. - Guzman et al – progressive shortening of the endocervical canal length to less than two cm. Or single length of less then two cm. Between 15

and 24

wks. Gestation competent

cervix had a non-significant rate of endocervical shortening of 0.0 cm per week while incompetent cervix had a rate of 0. cm per week. - Wong et al – greater than

decrease in cervical length in the

upright position compared to the supine position was associated with a significantly risk of preterm delivery when

compared with those with less than

decrease in cervical

length(87. versus ,p,0.00 .). Also found That when a cervical length of less than cm was combined with postural change, the the sensitivity for prediction of preterm delivery was 00 . - Mahram suggested that an internal Os diameter of 15mm or more in the first trimester or 20mm or more in the second trimester was diagnostic of incompetent cervix. - Varma et al considered an endocervical canal width of greater than 7mm with herniation of amniotic membrane an ominous sign. THE SERIAL USS WILL SAVE A NUMBER OF WOMEN FROM UNNECESSARY INTERVENTIONS Other tests to exclude other causes of recurrent pregnancy losses: Diabetes mellitus Thyroid dysfunction Lupus anticoagulant Chromosomal anomalies Cervical infections with organisms such as mycoplasma and ureaplasma

TRE ATME NT In women with classic history: Usefulness of surgical procedures are questioned CE RCL AGE TE CH NI QUES Timing of the procedure: (i) preconception – Lash and Lash - 1950 (ii) during pregnancy - Cervical cerclagestransvaginal or transabdominal - The transvaginal techniques: – the Shirodkar’s, McDonald’s procedures and the Wurn’s procedure. - McDonald procedure is the preferred method. - As an elective procedure in early second trimester (14 – 16 weeks). - Before the cerclage, ultrasound scan should be performed to rule out fetal structural anomalies. Pregnancies which may have terminated spontaneously in the first trimester presumably because of fetal chromosomal anomalies are not maintained by cervical cerclages. Also after the first trimester anaesthetic agents are better tolerated by the foetus. CON TR AI NDI CATIO NS - Uterine bleeding - Ruptured membranes - Uterine contractions - Major Fetal anomalies - Vaginal or cervical infections – this should be treated before the cerclage. Sutures used: Anaesthesia:

MCD ONALD P ROC ED URE - Patient is placed in a lithotomy position and after cleaning and draping the bladder is emptied. - A speculum (sims or Auvald) is applied to retract the posterior vaginal wall and enable the cervix to be visualized. - 2 sponge – holding forceps, each applied to the anterior and posterior cervical lips and the cervix drawn down. - The junction of the rugose anterior vaginal mucosa with the smooth cervical mucosa is identified, which corresponds approximately to the level of the internal os. - Placement of the cerclage suture is stated just below the above mentioned junction (in order to avoid the bladder) and four or six bites are taken circumferentially to complete a purse – string. - The first bite is taken starting from just before 12 O’clock and with the last bite the needle comes out just after 12 O’clock. The suture is placed deep into the cervical tissue, but not through the endocervical canal. - The needle is then removed and the suture pulled and knotted tight enough anteriorly to almost close the internal os; about four throws are used for the knot and the suture ends left long (2-3cm) to facilitate identification and manipulation when it comes to removal. SH IRODKAR P ROCED URE - The initial steps in this procedure up to the identification of the junction of the rugose anterior

-

-

-

-

vaginal mucosa with smooth cervical mucosa are the same. A transverse incision about 2cm long is made just below the junction and the bladder dissected away by blunt dissection using the gloved finger until the uterovesical peritoneal fold is reached. The cervix is then pulled forward toward the symphysis pubis, the junction of the rugose posterior vaginal mucosa with the smooth cervical mucosa is identified and another transverse incision about 2cm long made just below the identified junction. In the original procedure, an aneurysm needle was used to pass the suture submucosally round the cervix, from the posterior incision, into the anterior. In current practice a large atraumatic needle may be used to achieve the same results. The knot is tied anterioly anchored to the cervix with a couple of 3-0 silk sutures and the vaginal mucosa repaired with the knot buried. The suture is anchored to the cervix posteriorly with a single 3 – 0 silk suture and the posterior vaginal mucosa repaired.

POST CE RCLA GE M ANAGE MENT - Perioperative antibiotic therapy is advisable. - Use of tocolytics in the perioperative period is controversial. - Bed-rest may be advised for the first 24 hours. - Patient may be discharged home after a couple of days.

-

However, in some cases the obstetric history is such that both the doctor and the patient feel more comfortable if the patient remained in hospital – especially when there have been previous cerclage failures. - On discharge, they are advised to avoid coitus or the insertion of any object in the vagina. - They may gradually resume normal activity but must avoid strenuous physical activity. - They are advised to report any increased vaginal discharge, vaginal or backpressure or pelvic cramps. - Routine antenatal clinic attendance schedule may be examined every fortnightly or so to determine the intergrity of the cerclage. - Removel - 37 – 38 weeks gestation. However it is removed earlier if there is: Excessive vaginal bleeding, intra-uterine fetal death, persistent uterine contractions, rupture of the membranes. With McDonald’s suture removal can be performed without anesthesia, but with Shirodkar’s because of the need to incise the vaginal mucosa and dissect in order to access the suture, general anesthesia may be required. EMER GE NC Y CER CLA GE Indications:- cervical effacement and dilatation without uterine activity detected in index pregnancy. - while managing conservatively with serial digital examination or ultrasound scan cervical incompetence is diagnosed.

The fetal salvage rates of emergency cerclage are considerably less than those of the elective procedure. The incidence of complications, often due to infection is high. Many patients require prolonged hospitalization or bed rest and few reach full term. In spite of these, it is recommended as it may be the only way of prolonging pregnancy in the situations in which they are required. PRE -O PER ATI VE PREP AR ATIO N After the diagnosis, pt is placed on bed rest in the trendelenburg position and uterine activity closely monitored. An ultrasound is performed to evaluate the foetus and tocolytics administered if necessary. No contraindication to insertion of cerclage suture. Cervical cultures should be obtained to rule out infection with specific organisms such as beta haemolytic streptococci. Prophylactic antibiotic is given and 24 hours delay is also observed, so that cerclage is not inserted in a woman who is on the process of aborting spontaneously. BUL GI NG ME MB RAN ES AND CE RCL AGE Is a problem in emergency cerclages. (A) - A foley catheter with 20ml balloon in which the distal and has seen cut off flush with bulb may be used. The inflated bulb holds the membranes away from the internal os while the cerclage suture is

placed after which the bulb is deflated and the catheter removed. (B) - Use of 6-10 stay sutures placed at the edges of the cervix (with the patient in deep trendelenburg position) traction on which causes the membranes to move back into the uterine cavity. (C) - Bladder distension with up to 1000ml of normal saline may lead to a retraction of the membranes into the uterine cavity and allow cervical cerclage. (D) - An infatable bag has also been used to reduce bulging fetal membranes (F) - Trans-abdominal amniocentasis to temporarily reduce amniotic fluid volume and tension and assist in spontaneous reduction of fetal membrane prolapse. TR ANS -A BDO MIN AL CE RVI CA L CER CL AGE (TACC)

Beneficial in patients with cervices that either are extremely short, congenitally deformed, deeply lacerated (impossible to pass a vaginal suture) or previously failed trans-vaginal cerclage procedures. Pre-conceptional procedures: between 10 and 14 weeks, after ultrasound has confirmed fetal viability. A midline sub-umbilical or a pfannenstiel incision. The uterovesical peritoneal fold is incised transversely at its reflection onto the uterus and the bladder flap carefully dissected downwards by blunt dissection, taking care to avoid injury to the venous plexuses present laterally. The uterus is brought up into the abdominal incision. The uterine artery on one side of the cervix is visualized splitting into ascending and descending

branches; the relative avascular space medial to the branches of the uterine artery but lateral to the cervix is identified and enlarged. A 5mm mersilene tape swedged onto a needle is placed through the avascular space from anterior to posterior. The same process is repeated on the order side, this time passing the suture from posterior to anterior. The band is tied snugly anteriorly in the region of the internal os with a single knot and the free ends of the knot secured to the tape by no 3-0 silk sutures placed about 1-2cm from the knot. The bladder flap and the abdomen are closed routinely. Caesarean section is required for delivery, the cervical cerclage is left in place for future pregnancies. Where a preterm fetus needs delivery, laparotomy may be required to divide the band. Laparoscopy COM PLI CA TIO NS - Haemorrhages. - Cervical trauma, uterine contractions and rupture of fetal membranes which is more likely to occur during emergency cerclage. - Post-operative complications include: infections(chorioamnionites) and suture displacement. - Other late complications are – fistula formation and cervical stenosis - Scaring may cause cervical dystocia in labour, or result in deep cervical lacerations, which may extend to the broad ligament.

- Puerperal pyrexia is more in patients with cerclages. - Potential fetal sequelae include prematurity, sepsis and intra-uterine death.