Labor Pain Management: Neuraxial Analgesia

Labor is a natural physiological process, but it generally involves severe pain and discomfort. Every mother’s labor and delivery experience is unique. We at BJU are dedicated to tailoring our care for each mom to be, providing them with an individualized birthing plan, including various options for labor analgesia. Below, we have summarized the most frequently asked questions related to labor analgesia so that you may be prepared to make informed decisions.

How painful is childbirth?

For most women, pain during childbirth is the most severe that they will experience in their lifetime. 50% of women feel that the pain is hard to endure and 44% consider the pain to be excruciating. The pain may cause stress reactions, such as increased blood pressure, increased

heart rate, hyperventilation, hypoxia, dehydration, and an increased level of circulating catecholamines. These reactions may affect regular contractions of the uterus and may become life-threatening for both the mother and baby.

What are my pain-relief options during labor?

Various pharmacological and non-pharmacological approaches are available to relieve pain during labor. Non-medication therapies include doula labor, breathing techniques with relaxation, massage, acupuncture, birth ball, water birth, and others. Medication therapies include intravenous analgesia, and neuraxial analgesia (epidural or combined spinal-epidural). Of those, neuraxial analgesia is by far the safest and most effective option.

What is epidural analgesia?

Epidural analgesia is achieved by administering local anesthetics and analgesics through a catheter threaded through a needle that is inserted into the epidural space in the patient’s back. The catheter is taped to the back to prevent it from slipping out. The medication usually takes effect within 15-30 minutes and can last until the baby is delivered. Prior to epidural analgesia, your midwife will give you intravenous fluids. Once the epidural analgesia is started, you will be able to self-administer the medication to control your pain by pressing the button on the handle of the analgesic pump.

Because the medication used for epidural analgesia is of a different intensity from the anesthesia used in cesarean sections, a patient receiving epidural analgesia for labor can still move her body and feel the uterine contractions. There may be bearable pain when the patient pushes during full dilatation.

After the epidural analgesia is administered, your legs may feel slightly numb, so getting out of bed is NOT recommended. Your blood pressure will need to be measured every 5-10 minutes for the first half hour after epidural, and rapid fluids will be administered if necessary. If your epidural analgesia (infusion) continues for more than a few hours, you may develop a fever. If this occurs, your doctor will provide appropriate treatments including fever reduction, fluid rehydration, or antibiotics depending on your specific condition at the time.

Does epidural analgesia completely relieve the pain?

Epidural analgesia doesn’t make the whole process painless. Our goal for labor analgesia is to bring your pain down to a visual analogue score (VAS) of less than 4, which can benefit the labor process.

Can I have epidural analgesia during labor?

Epidural analgesia can be given to patients who have regular uterine contractions with cervical changes. It will be given based on maternal request. In other words, maternal request is a sufficient indication for pain relief during labor, barring any medical contraindications.

Contraindications include:

• Puncture site infection or skin damage
• Dysfunction of blood coagulation
• Decreased platelet count
• Neurological function abnormality of the lower limbs
• Neurological diseases
• History of spine surgery, trauma, or deformity of the spine
• Inability to cooperate with the procedure

How can I prepare for epidural analgesia?

One way to prepare for labor is by understanding your epidural analgesia plan. During the actual process of delivery, you will have different requirements. In order to make the process smooth, please be aware that there is a chance that the plan may need to be adjusted. Some mothers prefer to avoid any analgesics if possible. There are some methods to relieve pain, like patterned breathing, massage, warm water bath or shower, yoga, walking, and other techniques that can help relaxation. If the pain becomes unexpectedly severe or the birth process is not as smooth as it should be, analgesics have to be given to relieve the pain.

The most frequently used approach is epidural analgesia, which is also recommended by most obstetricians. Epidural analgesia has been proven to be the most effective way to control pain and has the smallest impact on both the mother and the baby. Epidural analgesia is performed by an anesthesiologist. You can book an appointment at the pre-anesthesia clinic for further information. The anesthesiologist will also evaluate your past history and inform you of any particular risks involved.

What are the benefits of relieving labor pain with epidural analgesia?

• Epidural analgesia may inhibit stress reactions andimprove the maternal environment for the baby, which in turn sustains adequate blood supply to the fetus;
• Epidural analgesia makes contractions regular andcoordinated, thus increasing the force of labor and accelerating the labor process;
• Epidural analgesia helps reduce the rates of lateralincisions and perineal lacerations;
• Epidural analgesia helps achieve a natural delivery, whichis safer for mothers;
• Epidural analgesia may reduce the rate of postpartumdepression;
• Epidural analgesia provides the patient with a morepleasant way to deliver naturally and enjoy the process. It also reduces the family’s concerns regarding the pain of childbirth.

What are the risks of epidural analgesia for the fetus?

Although trace amounts of analgesics may be transferred to the fetus via the placenta, many studies have shown that this may not affect neonates. Only in a few cases does the transient fetal heart rate decrease, and this can usually be relieved by oxygenation and lateral positioning.

What are the risks of epidural analgesia for mothers?

Force of labor

Ropivacaine is a nerve blocker that separates sensation and movement, which means the patient will not feel pain but can still move. Patients may sometimes experience heaviness or numbness in their legs.

Effect on the labor process

The medication causes no change to the first stage of delivery and may prolong the second stage slightly. There is an increased rate of assisted vaginal delivery by vacuum extraction or forceps when epidural analgesia is used.

Effect on normal delivery success rate

Epidural analgesia does not increase the cesarean section rate.

What are the risks and possible complications of an epidural block?

Epidural blocks are safe in general. Any procedure has its side effects and complications, but commonly these adverse effects are transient or reversible.

The risks depend on:

• Whether you have co-existing diseases;
• Your medical condition (e.g. being overweight or having ahistory of complications from anesthesia).

Intrathecal block includes epidural block and combined spinal and epidural anesthesia. Below are common side effects and complications:

• Nausea and vomiting;
• Itching and chills
• Fever during labor
• Slight decrease in blood pressure (intravenous therapywill be set up before administration of epidural analgesia to prevent blood pressure change)
• Headache（the incidence is about 1-3‰, and it is a headache related to body position change, which can be relieved naturally in about a week, and can also be immediately relieved by means of re-intervention）
• Back pain or redness and swelling at the point ofpuncture
• Numbness of the legs (commonly transient and candisappear over time. Severe nerve complications are rare)
• Sometimes not as effective as expected (a repeatpuncture might be considered)
• Difficulty in urination (may be solved by temporarycatheterization)
• Epidural hematoma or bleeding (this is a very rare butsevere complication. If you take any anticoagulants, please tell the anesthesiologist. He/she will decide whether you are a candidate for epidural analgesia according to your situation)

What should I keep in mind when I get epidural analgesia?

The pain level for a local anesthesia injection is generally less than it would be after a peripheral venous puncture. You might feel soreness in your lower back during the epidural

puncture. If you have a contraction during the procedure, please do stay still and inform your anesthesiologist. If there is any discomfort, let your anesthesiologist know. Lying on your back with your head slightly raised for 30 minutes will help the medication distribute better. During labor, you can use the button on your medication-control device to add more anesthetic to control the dose yourself. Pain might be recurrent and augmented in the late stages of labor which will be taken care of by the anesthesiologist.

If I am given an epidural for a vaginal delivery but need to switch to a C-section delivery, what type of anesthesia will I have?

In this situation, generally speaking, anesthetics will be given via the epidural catheter rather than by making a puncture again. The obstetrician and anesthesiologist will evaluate together and then decide. If the labor process takes too long, with unsatisfactory effects from the refill of medicine, there may be a chance of a repeat puncture. Additional analgesics and sedatives might be given during surgery. If the C-section needs to be performed urgently, general anesthesia will be used.

Can I eat during labor?

There is always a risk of reflux and aspiration during delivery, whether it’s a vaginal delivery or a C-section. Reflux is when gastric contents come back out of the stomach and into the throat due to achalasia cardia or increased gastric pressure. Aspiration of gastric contents into the trachea, due to the pharyngeal reflex slowing or disappearing, will cause airway obstruction or aspiration pneumonia. Under anesthesia, the risk of reflux and aspiration increases. Here are some food recommendations for women about to deliver:

• Women about to deliver can have liquid food or a lightmeal (e.g. bread, vegetables, biscuits, sports drinks, or juice);
• Women with a high risk of aspiration related to eatingduring labor should adhere to a more restrictive diet. This includes overweight women as well as those with clinical conditions such as severe upper gastrointestinal disorders, gastric esophageal reflux, or having any indications
• for emergency C-section. You may wish to consultyour anesthesiologist for more details.
• Women who are going to have an elective C-sectionshould follow these instructions for fasting:
• You may have a heavy meal (such as steak or seafood)eight or more hours before the start of anesthesia;
• You may have a light meal (such as milk and bread) six ormore hours before the start of anesthesia;
• You may drink clear liquids (such as plain water, applejuice, or black coffee) two or more hours before the start of anesthesia.

All labor analgesia in the context of this article refers to intrathecal analgesia. Epidural analgesia is the most frequently used analgesia for labor at BJU.

Author：XU GUOXUN   TAO YIFAN   YANG LU

REFERENCES

1. ACOG Practice Bulletin No. 209 Summary: Obstetric Analgesia and Anesthesia. Obstet Gynecol 2019; 133:595.
2. Practice Guidelines for Obstetric Anesthesia: An Updated Report by the American Society of Anesthesiologists Task Force on Obstetric Anesthesia and the Society for Obstetric Anesthesia and Perinatology. Anesthesiology 2016; 124:270.
3. ACOG Committee Opinion No. 295, Pain Reilief During Labor, July 2004 (replaces No. 231, February 2000; reaffirmed 2015). http://www.acog.org/Resources-And-Publications/Committee-Opinions/Committee-on-Obstetric-Practice/Pain-Relief-During-Labor (Accessed on May 19, 2016).