妊娠期间腹腔镜手术.doc

Laparoscopic surgery during pregnancy妊娠期间腹腔镜手术Yuen Pong Mo 阮邦武Consultant & Director of Gynaecological Endoscopy, Department of Obstetrics and Gynaecology, Prince of Wales Hospital, Hong KongHonorary Clinical Associate Professor, Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong KongPresident, The Hong Kong Gynaecological Endoscopy Society The advance in technology and skills in operative laparoscopy has revolutionized the surgical approach to many different procedures in gynecology and other surgical specialties. Many conditions that were previously considered as a contraindication to laparoscopy can now be operated on using this approach. Pregnancy, especially in more advanced gestation, was considered as an absolute contraindication for laparoscopy. This is probably because of the fear of injury to the enlarged pregnant uterus, resulting in leakage of amniotic fluid, bleeding, abortion and even gas embolism. The creation of pneumoperitoneum and the use of carbon dioxide may decrease uterine blood flow, resulting in fetal hypotension, hypoxia and acidosis. The relative lack of space available for surgical manipulation further limits the possible procedures that can be performed. However, over the last decade, more and more case reports and retrospective studies have appeared and reported the safety of operative laparoscopy during pregnancy. Non-obstetric surgery is performed in 1.6-2.2% of pregnant women, but operative laparoscopy during pregnancy has been limited largely to appendcectomy, cholcystectomy and removal of adnexal mass.Laparoscopic Adnexal SurgeryThe reported incidence of adnexal mass complicating pregnancy ranges from 1 in 81 to 1 in 2,500 live births, with an average of 1 in 600. Corpus luteal cysts account for a third of the adnexal masses and benign cystic teratomas contribute to another third. Surgical removal of the mass during pregnancy is associated with a significant increase in fetal loss, especially when performed during the first trimester or in an emergent situation. It has been suggested that all persistent adnexal masses should be electively removed at second trimester to avoid delay in the diagnosis of a possible malignancy and to avoid the risk of complications, as functional corpus luteal cyst would have regressed by then.The incidence of malignancy in an adnexal mass in pregnancy is reported to be 2-8%. It has been suggested that ultasonography of an adnexal mass in pregnant women could be used to distinguish benign from malignant lesions, and unilocular cysts could be managed conservatively. However, sonographically simple cyst does not exclude malignancy, in particular borderline malignancy, and the reported incidence varies from 1.5% to 20%.Retrospective reviews of the outcome of pregnancies with adnexal masses found that 13-42% of cases resulted in complications in the second half of gestation, often necessitating urgent surgical intervention. The risk of torsion is estimated to be 6.5% to 50% and that of cyst rupture is 9% to 17%. Emergency surgery is associated with a higher fetal wastage rate compared with elective surgery. The risk of obstruction of labor is 17-21%. The complications are more likely if the mass are greater than 5-6 cm. These acute presentations are associated with increased fetal morbidity and mortality, primarily due to premature delivery.There have been worries about the effect of surgery on the pregnancy and the fetus. A large registry study of pregnancy outcomes following non-obstetrical surgery identified an increased incidence of low and very low birth weight infants, and an increased incidence of infants born alive but dying within 7 days. Patients undergoing laparotomy before 23 weeks had significantly fewer adverse pregnancy outcome than those after 23 weeks with an odds ratio of 0.15 (95% CI 0.03-0.69). The current data suggest that laparotomy for adnexal mass during second trimester of pregnancy do carry a 3 to 6% risk of fetal/perinatal morbidity. Despite the advance in operative laparoscopy in the management of adnexal masses, laparoscopy has not been widely performed during pregnancy. Two recent reviews of the current literature could only identify a few small series and case reports concerning laparoscopic adnexal surgery during pregnancy (Error! Reference source not found.,Error! Reference source not found.). Virtually all the procedures performed after the first trimester of pregnancy reported uneventful operation and good pregnancy outcome. Although these procedures are performed with increasing frequency to date, the use of laparoscopy during pregnancy is still uncommon. Since the report of our initial experience in laparoscopic management of persistent ovarian masses in the second trimester of pregnancy in 1997, we have adopted laparoscopy as the standard approach to this condition. Over the past 9 years, we have operated on 67 cases with minimal morbidity. Our result is very encouraging. The conversion rate was only 3% and this occurred early in our series. Abortion occurred in only one pregnancy (1.5%) which was unlikely related to the operation as it happened 6 weeks afterwards. There appears to have no effect on future fertility potential. Surgical TechniqueLaparoscopy during pregnancy is best performed with the patient in the supine position. The conventional dorso-lithotomy position should be avoided as manipulation of the uterus through the cervix cannot be used. The lithotomy position may also cause undue pressure on the legs, thereby increasing the risk of deep vein thrombosis which pregnant women are more susceptible. There is usually no difficulty in exposing the adnexal mass as the enlarged pregnant uterus tends to displace it towards the top of the uterus. Even when the mass is situated in the pouch of Douglas, mobilization of the mass has not been a problem. The exposure of the adnexal region can further be facilitated by the head down position and lateral tilt of the patients.Open laparoscopy should be employed for primary trocar insertion. This avoids the risk of penetrating injury to the pregnant uterus by either the Veress needle or the trocar cannula. Very often the primary trocar needs to be inserted supraumbilically and it should be at least 6 cm from the uterine fundus. This would allow an adequate distant between the tip of the laparoscope and uterus for proper visualization of the abdominal cavity and a wide surgical field for ease of instrument manipulation without changing the visual angle. Similarly, secondary trocars must be inserted under direct vision in a controlled manner. The exact sites for the secondary trocars should be individualized to allow easy manipulation of the adnexal mass and avoidance of the uterus.Effects of PneumoperitoneumThere is no evidence to support any detrimental effect of the CO2 pneumoperitoneum on the fetus. It has been demonstrated that operative laparoscopy has little effect on maternal blood gases. Given the hyperdynamic nature of the pregnant circulation, any CO2 that diffuses across the placenta should be rapidly removed. A recent study on the fetal response to CO2 pneumoperitoneum in the pregnant ewe confirms the lack of adverse effects of CO2 insufflation on the fetal placental perfusion and blood gases. In our series all the fetuses have not demonstrated any adverse effect, the pregnancy and neonatal outcome were all normal. However, the absolute safety of this procedure during pregnancy has as yet to be established. As in laparoscopy on a non-pregnant woman, the intra-abdominal pressure should be maintained at a pressure below 15 mmHg to prevent ventilatory and circulatory problems, and the risk of gas embolism. The potential effect of carbon dioxide pneumoperitoneum on the pregnancy is unknown. Provided that the end tidal CO2 level is monitored and maintained within the normal range throughout the operation, insufflation of CO2 should not have any significant effects on the metabolic milieu.Laparoscopic Surgery for Adnexal TorsionAdnexal torsion is an uncommon occurrence during pregnancy. Its incidence is reported to be 1 in 5,000 pregnancies with the highest incidence during the first trimester of pregnancy. The condition is rare during the second or third trimester of pregnancy. Diagnosis of the condition is frequently delayed, resulting in ischaemia and even infarction of the adnexa. Traditionally, adnexal torsion has been treated by adnexectomy without untwisting the adnexa especially when it has become gangreneous and necrotic. However, there are increasing reports of successful preservation of the ovarian function without increasing morbidity following de-torsion and cyst puncture or removal irrespective of the degree of ischaemia and the macroscopic appearance. However, the experience during pregnancy is very limited. There is a concern that the inflammatory reaction following this “adnexal-sparing” approach may irritate the peritoneum and uterus, resulting in a higher risk of miscarriage and premature labour. Until there is more solid evidence in supporting this conservative approach, adnexectomy is still the standard procedure during pregnancy.Laparoscopic treatment of heterotopic pregnancyHeterotopic pregnancy is the co-existence of intra- and extra-uterine pregnancy. It is extremely rare in spontaneous pregnancies with an estimated incidence of 1 in 30,000 pregnancies. However, with the wide spread use of assisted reproductive techniques, the incidence may be as high as 1:100 to 1:500. So far there are 22 cases of laparoscopic treatment of heterotopic pregnancy being reported. All cases were diagnosed in the first trimester of pregnancy. Of the 19 tubal heterotopic pregnancies, salpingectomy was performed in 16 and salpingostomy in 3. For the 3 cornual heterotopic pregnancies, 2 underwent corneal resection and one cornuostomy. Following the procedure, there were 3 miscarriages and one fetal death after chorioamnionitis at 26 weeks.Laparoscopic AppendectomyAppendicitis is the most common indication for non-obstetric abdominal surgery in pregnancy. The incidence is estimated to be around 0.5-1 per 1,000 pregnancies. Appendicitis during pregnancy poses significant diagnostic and management challenges due to the displacement of the appendix by the gravid uterus and the leucocytosis associated with pregnancy. Delay in the diagnosis is not unusual, resulting in rupture of the appendix and increasing the fetal and maternal morbidity and mortality. Laparoscopy allows the performance of both diagnostic and therapeutic procedure at the same time, reducing the inherent risk associated with exploratory laparotomy. Laparoscopic CholecystectomyPregnancy is associated with an increased incidence of cholelithiasis, but most women are asymp