What if You Need Anesthesia and Surgery While Pregnant?
What if I Need Surgery While I'm Pregnant?
Only very necessary surgery is performed on pregnant women. As expected, there are risks to both the mother and fetus from the stress of surgery and anesthesia, and from direct effects of both. Before deciding to operate on a pregnant woman, it must be clear that the risks of NOT operating outweigh the risks of doing so.
As a physician anesthesiologist, I know that there will need to be a team-approach and discussion about the risks and benefits of how and when to do the surgery. We take this approach each time to keep you and your baby as safe as possible if you need to have surgery while you are pregnant.
It is not a decision that is entered into lightly. If your surgeon or obstetrician says you need surgery, you probably do. If you aren't comfortable with their decision, you can ask for another opinion, but this may not be practical in an urgent situation.
(From the anesthesiologists point of view, it usually goes something like this... "Doctor, we have an add-on surgery for you. The patient is a healthy 30 year old and needs to have her appendix out as she is having pain and has signs of infection. Oh, and by the way, she's pregnant.")
Have you had surgery while pregnant
The Most Common Nonobstetric Surgeries on Pregnant Women
- Cholecystectomy (removing gall bladder)
- Ovarian Surgery (often for twisted ovary)
- Trauma Surgery after an accident
- Cervical Surgery (especially "cerclage" to prevent preterm delivery)
- Breast Surgery (when it can't be delayed until after pregnancy)
- Emergency Surgery for Dangerous Bowel Obstruction
What are the Most Common Surgeries on Pregnant Women?
In the United States, about 80,000 surgeries are performed on pregnant women each year. This means that 1 to 2 percent of women will undergo surgery while pregnant.
As in the example, appendicitis is the most common reason for a woman to have surgery while pregnant. Appendectomy on a pregnant woman can be done by either a laparoscopic (camera and instruments placed through small incisions) or open (one incision in the right lower abdomen). Both techniques have advantages and disadvantages and you should discuss this with your surgeon as each case must be decided on its own specifications.
Gallbladder surgery usually can be delayed until after delivery with pain managed medically during pregnancy. Occasionally, the gallbladder is so inflamed, blocked by stones or infected that it has to come out to prevent more serious illness. This is usually done laparoscopically.
Ovarian torsion (twisting) causes severe pain and puts the ovary at risk of "dying" by cutting off its blood supply. Ovarian cysts are also relatively common during pregnancy. Laparoscopic surgery is usually the method of choice for ovarian surgery when pregnant.
Cervical cerclage is done during pregnancy to prevent the cervix from dilating and leading to a resultant preterm delivery.
Trauma surgery usually follows a motor vehicle accident, although other accidents may also require surgery.
Breast and bowel surgery may also have to happen on an urgent or emergent basis.
Risks to Mother of Non-Obstetric Surgery While Pregnant
There are traits of pregnancy that make anesthesia more risky. Changes in nearly every organ system occur due to hormonal and anatomic alterations. Anesthesiologists study these changes in detail and are prepared to provide anesthesia with the anatomy and physiology of the pregnant woman in mind.
Airway: Because pregnant women retain water, their soft tissue and mucosa around the airway (nose, mouth, throat) tend to "swell". This can make placement of a breathing tube more difficult. Indeed, this is one of the most dreaded obstacles for anesthesiologists. Once asleep, there is limited time to place the breathing tube and resume oxygen delivery before mom and baby are at risk. Luckily, our training includes recognition of and planning for this situation.
Swelling of the tissues around and over the windpipe can also present danger after surgery. Oxygen levels and breathing are monitored closely in the recovery room to make sure this isn't an issue.
Also, blood supply is increased to the airway of pregnant women and the soft tissues are more sensitive and fragile. Bleeding of the mucosa (lining) of the mouth or throat can cause the above difficult airway, or it may lead to irritation of the vocal cords (causing them to spasm closed after removal of the breathing tube, making oxygen delivery difficult).
Anesthetic Concerns: Your anesthesiologist is trained to know that the required amount of anesthesia is reduced by up to 40% during pregnancy. He or she will monitor you carefully to make sure you don't get too much -- or too little -- anesthesia.
Aspiration:By the 16th week of gestation, changes in the gastrointestinal system make heartburn and acid reflux very common. Even asymptomatic pregnant women are considered to be at risk. In the third trimester, the additional pressure placed on the stomach by the lower abdomen adds to the likelihood that acid could be pushed up from the stomach into the esophagus and all the way up to the throat where it can enter the windpipe and lungs.
Blood Pressure: A pregnant woman has a higher volume of fluid and blood circulating in her system. But, hormonal changes cause the blood vessels to relax a bit. The overall effect is a lower blood pressure that may decrease even more under anesthesia. Because a too-low blood pressure puts the baby at risk of not getting enough blood and oxygen, this is monitored and maintained very carefully by the anesthesiologist.
Breathing: While the breathing tube is in place (and it will be for general anesthesia), the ventilator can help you breathe. After surgery, you must take over this function again. Your oxygen reserves are reduced during pregnancy. Also, a large uterus can make it difficult to take deep breaths, especially while you are groggy. You will be monitored and reminded to do this regularly so your (and baby's) oxygen level doesn't drop.
Recovery: In the recovery period, your baby may be at risk of arriving early. This is especially true if you had to have surgery in the third trimester. The nurses in recovery (or on the OB unit) can monitor your uterine contractions and the baby's heart rate. Medications can be given if contractions start.
The risk of preterm delivery may persist for the rest of pregnancy. In addition, pregnant women are more prone to blood clots in their legs and lungs after surgery and should be encouraged to walk as their surgical and obstetric conditions allow.
For the Healthcare Provider
- Review of Nonobstetric Surgery during Pregnancy
A 2006 review of maternal physiology, maternal and fetal risk and a review of specific anesthesia considerations and recommendations.
Facts about Appendicitis in Pregnancy for Doctors
Risks to Fetus of Nonobstetric Surgery While Pregnant
Of course, all of the factors that cause complications in the mother, also put the baby at risk. The biggest concerns for the baby are BIRTH DEFECTS, MISCARRIAGE AND PRETERM DELIVERY.
BIRTH DEFECTS: There is no evidence that babies born to mothers who had surgery during pregnancy have a higher incidence of birth defects. Of course, designing a study where pregnant women are unnecessarily exposed to anesthesia and surgery, to establish this definitively is impossible to do (ethically). There is potentially some evidence that lower-birth weight may occur in these babies.
MISCARRIAGE: Miscarriage occurs in 1 to 2 percent of women who have surgery during pregnancy. It is unclear whether this is precipitated by the illness, the surgical procedure/manipulation or the anesthesia, or a combination.
PRETERM LABOR: As above, it is unclear why the risk of preterm labor seems to be increased, but most studies show a small increased risk of preterm labor after surgery in pregnant women. Some researches believe that anesthesia gases may relax the uterus and help prevent preterm labor, and therefore, recommend general anesthesia (as opposed to spinal or epidural).
TIMING OF SURGERY
The second trimester is considered the best time to perform surgeries on pregnant women that are necessary but not emergent. Organ development in the first trimester means there is a (theoretical) risk of abnormal development. By the third trimester, the risk of preterm contractions and delivery is increased.
One Woman's Story - Appendicitis during Pregnancy
FOR THE ANESTHESIA TEAM PERFORMING GENERAL ANESTHESIA
- Obtain an obstetrics consult
- Provide preop aspiration prophylaxis
- Consider intraoperative, continuous fetal heart rate monitoring
- Ensure left uterine displacement to maintain blood flow to uterus and placenta, especially after 20 weeks gestation
- Preoxygenate fully
- Perform a rapid sequence induction with difficult airway plans and equipment immediately available (ETT is mandatory after about 16 weeks)
- Use smaller endotracheal tubes
- Consider prepping before induction to minimize anesthesia time
- Maintain hemodynamics and CO2 carefully (obviously)
- Reassure your anxious patient that anesthesia during pregnancy is much safer than most people realize and problems are relatively rare
Recommendations from the Amercian Society of Anesthesiologists and American College of Obstetrics and Gynecology
The joint statement boils down to a few key points.
- Obtain an obstetrics consult
- No standard anesthetic agent is known to be teratogenic for a one-time exposure
- Urgent, but non-emergent surgery should be delayed until the 2nd trimester, when possible.
- Monitor the fetus with continuous heart rate and contraction monitoring IF
- the fetus is of viable gestational age (or positioning will be aided by monitoring)
- an obstetrician is available to intervene
- the patient consents to emergency c-section delivery and
- it is possible to do so
- otherwise, check fetal heart tones and uterine contractions before and after surgery
All in all, women tend to feel reassured after learning the facts about anesthesia and surgery during pregnancy. There is some risk, but it really tends to be lower than most people expect. Also, knowing that the doctors and nurses have faced this dilemma before helps the understandably anxious mother-to-be.
Feel free to leave comments or questions as I try to answer each one personally.