Medical Pain Management in Labour

While your final weeks of pregnancy are the time when you wait in anticipation for the new arrival, you may also be a little worried about the amount of pain you might have to bear while delivering. Most women cope with labour pain using medications, which have been broadly classified into analgesics and anaesthesia.

There are a number of options available for pain management. While some may be effective in the earlier stages of contraction, others are much more effective and a better choice during the later stages of delivery. Which you should use will depend on your preference, your health care providers preference and just how far advanced in labour you are.

Analgesics and Narcotics

Analgesics and narcoticas are the systemic medications for pain control that relieve pain without causing a loss of sensation. These drugs are actually more helpful in reducing the pain of contraction rather than completely stopping it.

Your doctor may administer these drugs intravenously or with an injection into a muscle and they affect the entire body rather than just the pelvic area. In some hospitals or clinics, you may also be given the ability to control your dosage using a button that injects a fixed dose intravenously.

The use of an analgesic or a narcotic is usually recommended during the first stages of labour, as closer to delivery a high dosage can affect the baby. The effect of these drugs lasts for around four to six hours and some mothers may complain of feeling drowsy or nauseous. It has also been observed that analgesic use may reduce the strength or frequency of contractions.

Common drugs used that fall under this category include butorphanol (Stadol), fentanyl (Sublimaze), and meperidine (Demerol).

Advantages

• They are helpful in minimising the pain and making it more bearable
• Can be administered easily as compared to an epidural or spinal block
• Help you to relax
• Do not cause any muscle weakness
• Some physicians suggest that women taking these drugs are less likely to take Pitocin or get a vacuum or forceps delivery.

Disadvantages

• May cause nausea, disorientation and drowsiness
• May depress respiration temporarily for the baby or mother if given in large doses.
• Less effective in total pain relief than epidurals
• They may sometimes interfere with foetal heart monitoring as they may affect the baby’s heart rate.
• Baby may be less alert at birth

Epidural Blocks

This is a combination of a local anaesthetic and a narcotic that continuously relieves pain in the lower part of the body. An epidural is given with a catheter into the epidural space, which surrounds the spine area of your body. A small test dose may first be administered to determine how the medication will affect you. Once it is deemed safe, a continuous flow may be administered with the help of a catheter. While receiving an epidural, the foetal heart rate is monitored continuously, as is the mother’s blood pressure. It takes about 20 minutes to administer an epidural block and another 20 minutes for it to take effect.

Using an epidural allows a mother to remain fully awake. Additionally, the baby should not be affected in any way. It is also possible to receive a "walking epidural," which still blocks the pain of labour, but leaves you with enough lower body strength and muscle to walk about. The combination of these two becomes much more affective than the two used separately.

Advantages

• Can be used throughout labour to relieve pain
• Dosage given can be continuously increased or decreased and a higher dosage can be given for a caesarean section
• Allows you to remain awake and alert
• Only affects the lower part of the body

Disadvantages

• May decrease blood pressure and in turn slow the baby’s heart rate
• The effect of the drug may be felt more on one side than the other
• Possibility of severe headaches due to leakage of spinal fluid
• Allergic reactions may occur
• It may prolong the pushing stage of labour because of numbing in the lower part of the body.
• Sometimes Pitocin may be required to quicken the process of labour
• Not advisable for women with low blood pressure, bleeding disorder, infections of the skin or those who have an allergy to anaesthesia.

Spinal Blocks

With this kind of medication a dose of anaesthetic and a narcotic drug is given through direct injection into the spinal fluid. The pain relief is speedy and the affect lasts for a few hours.

As compared to an epidural, a spinal block differs in two ways. First it is administered directly into the fluid surrounding the spine; secondly a catheter is not used, and instead a one-time injection is given. For someone who is fast reaching labour and does not have the time required for the administration or the delayed affect of an epidural, a spinal nerve block is a better choice. It is also suggested for women who want pain relief late in labour.

This medication is also used by doctors during caesarean sections as it not only gives pain relief but also helps in blocking the motor nerves making the mother feel totally numb from chest down. Some common spinal blocks use chloroprocaine or lidocaine as anaesthetics and fentanyl or meperidine as narcotics.

Advantages

• Quick and complete pain relief
• A very tiny amount of medication reaches the baby as compared to analgesics
• Mother can remain alert and awake

Disadvantages

• May decrease blood pressure as well as the baby’s heart rate
• Higher risk of headaches since it is injected directly into the spinal fluid
• The narcotic in the block may cause itchiness and nausea
• The reduced sensation may make it harder to push the baby.
• In rare circumstances, may cause temporary breathing problem

Combined Spinal Epidural Block

This method helps give quick pain relief like a spinal block as well as a continuous flow of drugs like an epidural block. The anaesthesiologist usually injects one epidural injection through the back and uses the same to connect the spinal block injection. Once the spinal block is injected into the fluid, the needle is then used to fix the catheter, which then gives the epidural block.

Advantages

• Provides quick pain relief initially
• In earlier stages you can easily walk around
• Through the epidural catheter the doctor can continuously monitor the flow of the drugs
• No affect on other parts of the body except the lower waist region
• The catheter can be used for giving anaesthesia during a c-section or for tubal ligation if you are having this done after delivery.

Disadvantages

• Frequent blood pressure monitoring as well as foetal heart rate monitoring is required
• It may slow down labour and the need for pitocin may arise
• May lower blood pressure
• Pain relief may affect one part of the body more than the other
• Some may complain of a headache

Pudendal Block

This is a localised pain relief option where the anaesthetic is injected into the vagina that numbs the vulva, vagina and the perineum. The affect of this injection lasts for a few minute to a couple of hours though it does not provide any relief for uterine pain. This block is mostly used during the second stage of labour or for an episiotomy or a tear during delivery.

Advantages

• Localised pain relief
• The mother’s ability to push is not affected
• No side effects on the baby

Disadvantages

• No relief from contraction pain
• If injected in the vein it may cause a fall in blood pressure or, rarely, unconsciousness
• Sometimes allergic reactions may occur

Tranquillisers and Barbiturates

These are used only rarely during pregnancy to relieve anxiety and give the mother more time to rest. They can be injected intravenously, taken orally or by an injection. Some common tranquillisers used are diazepam, promethazine or propiomazine and barbiturates are amobarbital, pentobarbital, and secobarbital.

Advantages

• Help to relax
• Relieve anxiety

Disadvantages

• Does not relieve pain
• May make you feel drowsy
• The baby may show less activity during birth