Laparoscopy during pregnancy

Initially pregnancy was considered an absolute contraindication to laparoscopic surgery. Recent clinical reports have demonstrated the feasibility, advantages and potential safety of laparoscopic surgery in the pregnant patient. However, concerns about effects of carbon dioxide pneumoperitoneum on mother and fetus persists, resulting in controversy and concern.

Two new considerations and challenging complexities to the issue. First, involves the altered physiology of the pregnancy condition that may change the biologic response to carbon dioxide pneumoperitoneum and position extremes. Second, involves the effects on the foetus which maintains the physiology distinct from that of adults. That can cause foetal acidosis and hypoperfusion.

The safest time to operate on the pregnant patient is during 2^nd trimester because risks of teratogenesis, miscarriage and preterm delivery are lowest. The incidence of spontaneous abortion is highest in the 1^st trimester that is 12%, decreasing to 0% by the 3^rd. During the 2^nd trimester there is 5 to 8% of preterm labour and premature delivery which increases to 30% in the 3^rd trimester. Finally the gravid uterus is not yet large enough to abscure the operative field as in the case during the 3^rd trimester.

Advantages and feasibility of Lap. Surgery during pregnancy[edit | edit source]

Potentially, laparoscopic surgery in the pregnancy patient should result in the proven advantages of laparoscopy seen in the nonpregnant patient like decreased pain, earlier return of gastrointenstinal function, earlier ambulation, decreased hospital stay and faster return to routine activity. In addition, a decreased rate of premature delivery due to decreased uterine manupulation, decreased foetal depression secondary to decreased narcotic usage and a lower rate incisional hernia may be seen in the pregnant patients.

Disadvantages and concerns about lap. Surgery during pregnancy:

Concerns about lap. Surgery in pregnant patients center on three areas.

1. Increased intraabdominal pressure can lead to decreased inferior venacaval return resulting in decreased cardiac output. The foetus is dependent on maternal haemodynamic stability. The primary cause of foetal demise is maternal hypotension or hypoxia. So a fall in maternal cardiac output could result in foetal distress.
2. The increased intraabdominal pressure seen with a pneumoperitoneum could lead to decreased uterine bloodflow and increased intrauterine pressure. Both of which could result in foetal hypoxia.
3. Carbon dioxide is observed across the peritoneum and can lead respiratory acidosis in both mother and the fetus. Fetal acidosis could be potentiated by the decreased venacaval return age.

Biliary tract disease:

Gallstones are present in 12% of all pregnancies and cholecystectomy is performed in 3 to 8 out of 10,000 pregnancies.

1. An uncomplicated open cholecystectomy in pregnant patient should be accompanied by a 0% maternal mortality, 5% foetal loss and 7% preturm labour.
2. Complications such as Gallstone pancreatitis or acute cholecystitis will increase maternal mortality to 15% and foetal demise to 60%.
3. Patients with uncomplicated biliary colic should be treated medically with nonfat diets and pain medications until after delivery. Patients who present in the 1^st trimester of pregnancy with crescendo biliary colic or persistant vomiting should be medically managed if possible until they are in the 2^nd trimester.

Pregnant patient in the 2^nd trimester of pregnancy who present with the above complications of biliary tract disease will need operative treatment during the 2^nd trimester after appropriate resuscitation. Patients with these complications who present in the 3^rd trimester of pregnancy should be treated conservatively until after delivery if possible or atleast until a gestational age of 28-30 weeks in order to maximized foetal viability.

Clinical Studies:

One clinical study has reported four fetal deaths following laparoscopic surgery. Three occurred during first post operative week and the last four weeks post operatively. The causes of death are unknown but might be related to prolonged operative time. The operative times in these four patients was 106 minutes compared to the average of 55 minutes seen in the other studies. The laparoscopic procedure was performed for pancreatities in three of these women and a perforated appendix in the forth. It is possible that foetal loss was the result of the inflammatory process itself rather than laparoscopy per se. There is a 4% foetal mortality rate for all reported. laparoscopic cholecystectomies. It compares favourably with a 5% foetal mortality rate seen with open procedures.

One study has retrospectively compared pregnancy patients undergoing open laparotomy to pregnant patients undergoing laparoscopic surgery and found the later resumed regular diet earlier, required less pain medication and were hospitalized for shorter time. These differences were statistically significant.

Another clinical study revealed 150 laparoscopic cholecystectomies in pregnancy patients. Average operative time 55 minutes and average length of stay was 1.3 days. There were no reports of maternal complications or death. Of 99 babies delivered at the time of publication, three were premature and one was born with hyaline membrane disease at 37 weeks gestation. The remaining 95 were fullterm and healthy. There were no intraoperative foetal deaths or complications.

Animal Studies:

Animal studies raise several concerns about the effects of a carbon dioxide pneumoperitoneum on the mother and fetus. Because of the complexity of the maternal-fetal unit, it is useful to summarize these individually:

1. In pregnant baboons, a carbon dioxide pneumoperitoneum held at 20 mm Hg pressure for 20 mitutes resulted in increased pulmonary capillary wedge pressure, pulmonary artery pressure and central venous pressure. The mothers developed a respiratory acidosis despite controlled ventilation and an increase in respitatory rate. One fetus developed severe bradycardia which responded to desufflation.
2. In pregnant ewes, no change in maternal placental blood flow was seen after 2 hours of 13 mm Hg pressure. However, maternal and fetal respiratory acidosis developed. Fetal tachycardia, fetal hypertension, an increase in intra-uterine pressure and a decrease in uterine blood flow were also seen in pregnant ewes undergoing a carbon dioxide pneumoperitoneum at 15 mm Hg.
3. Maternal respitatory acidosis and severe fetal respiratory acidosis are common findings in all studies utilizing a carbon dioxide pneumoperitoneum in pregnant animals. Changes in respiratory rate did not completely correct the problems. Despite these problems. One study demonstrated that the ewes delivered fulterm healthy lambs following intraabdominal unsufflation to 15mm Hg pressure with carbon dioxide for one hour.
4. The physiologic changes exhibited by the pregnant ewe and fetus during insufflation, with carbon dioxide are nor present with nitrous oxide. Fetal tachycardia, hypertension, and acidosis as well as maternal acidosis are not present when utilizing a nitrous oxide pneumoperitoneum in animal studies. Use of nitrous oxide as an insufflating gas in the pregnant woman has yet to be evaluated, but may prove to be safer than carbon dioxide.

Guidelines:

The following practices should be followed when performing laparoscopic surgery in the pregnant to minimize adverse effects on the fetus or mother. More information is given in the SAGES Guidelines for Laparoscopic Surgery During Pregnancy:

1. Place the patient in the left lateral decubitus positionas with open surgery to prevent uterine compression of the inferior vena cava. Minimizing the degree of reverse Trendekenburg position may also further reduce possible uterine compression of the vena cava.
2. Use antiembolic deviceto prevent deep venous thrombosis. Stasis of blood in the lower extremities is common in pregnancy. Levels of febrinogen and factors VII and XII are increased during pregnancy leading to an increased risk of thromboembolic events. These changes, coupled with the decreased venous return seen with increased intraabdominal pressure and the reverse Trendelenburgposition used during laparoscopic surgery, significantly increase the risk of deep venous thrombosis.
3. An open Hasson technique for gaining access to the abdominal cavity is safer than a closed percutaneous puncture. Several authors have inserted a Verres needle in the right upper quadrant without complications, but the potential for puncture of the uterus or intestine still sxists, especially with increasing gestational age.
4. Maintain the intraabdominal pressure as low as possiblewhile still achieving adequate visualization. A pressure of less than 12-15 mm Hg should be used until concerns about the effects of high intraabdominal pressure on the foetus are answered.
5. Continuously monitor maternal endtidal CO2and maintain it between 25-30 mm by changing the minute ventilation. Promptly correcting any evidence of maternal respiratory acidosis is critical as the fetus is typically slightly more acidotic than the mother
6. Use continuous intraoperative fetal monitoring. If fetaldistressis noted, release the pneumoperitoneum immediately. Monitoring should be used even if the fetus is not viable, as the desufflation may reverse fetal distress, preventing serious problems. Transabdominal ultrasound fetal monitoring may not be effective because the establishment of the pneumoperitoneum may decrease fetal heart tones, so intravaginal ultrasound may be necessary for intraoperative monitoring.
7. If intraoperative cholangiography is to be performed protect the fetus.
8. Minimize operative time. Several studies have demonstrated a correlation between the duration of a carbon dioxide pneumoperitoneum and an increase in PaCO2.
9. Tocolytic agents should not be administered prophylactically.but are appropriate if there is any evidence of uterine irritability or contractions.
10. Trocar placement.
    1. Biliary tract disease: Place a Hasson trocar above the umbilicus. Place the remaining ports under direct visualization in the usual locations.
    2. Appendicitis/diagnostic laparoscopy: Place a Hasson trocar in the subxiphoid region. Insert the camera and locate the appendix or other inflammatory process. Insert the remaining trocars in locations appropriate to the pathology. For appendicitis,this wil usually be the right upper quadrant at the costal margin and in the right lower quadrant. Occasionally an additional port might need to be placed just above the uterus. If the uterus is too large and appendectomy cannot be performed laparoscopically, then laparoscopic visualization of the appendix may help determine the best location for the open incision.

Conclusion:

In conclusion,animal studies indicate that a carbon dioxide pneumoperitoneum causes fetal acidosis which may not be corrected by changes in maternal respiratory status. These intraoperative findings do not appear to have any longterm adverse effects on the fetus. The pregnant patient clearly benefits from laparoscopic surgery and should be offered this option as long as the above guidelines are followed.

References[edit | edit source]

1. THE SAGES MANUAL, Fundamentals of laparoscopy and GI Endoscopy SAGES, Society American, Gastrointestinal, Endoscopic Surgeons 98-103.
2. Mastery of Endoscopic and laparoscopic surgery, Edited by W.Stephen Eubanks, Lee L. Swanstrom, Nathaniel J. Soper.
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10. Kammerer WS. Nonobstetric surgery during pregnancy. Med Clin North Am 1979;63:1157-1163.
11. Mckellar DP, Anderson CT, Boynton CJ, Peoples JB, Cholecystectomy during pregnancy without fetal loss. Surg Gynecol Obstet 1992;174:465-468.
12. Motew M, Ivankovich AD,Bieniarz J, Albrecht RF, Zahed B, Scomegna A.Cardiovascular effects and acid-base and blood and blood gas changes during laparoscopy. Am J Obstet Gyncol 1973 113:1002-1012.
13. Reedy MB, Galan HL, Bean JD, Carnes A, Knight AB, Juehl TJ. Laparoscopic insufflation in the gravid baboon:maternal and fetal effects.J Am Assoc Gynecol Laparoscopist 1995;2:339-406. Soper NJ, Hunter JG, Petri RH. Laparoscopic cholecystectomy in the pregnant patient. Surg Laparosc Endosc 1994;4:268-271.