It’s always interesting to address the concerns about epidural anesthesia during labor.  While there are a number of common questions, epidural anesthesia has taken on almost a mythical status for some patients, and it’s kind of incredible to hear what is attributed to this type of pain relief during labor.  Here I’ll try to offer some insight on epidurals, how they work, and how they do (or don’t) affect labor and delivery.

First, what is an epidural?  An epidural is regional anesthetic.  This means, as opposed to IV pain relief, it isn’t expected to go into the blood stream, make you loopy or cross the placenta to the baby and sedate him/her.  A simple way to think of the difference between an epidural and a spinal is that typically an epidural procedure involves placement of a small catheter attached to a pump for continuous, but usually lighter, anesthesia than a one-time injection in a spinal.  If you think about it, that makes sense.  Pushing and movement are required during labor whereas we don’t want you moving anywhere during a cesarean section.  Some techniques involve a combination of the two, but that’s probably best explained by an anesthesiologist.

So, does an epidural slow down labor and increase risk of cesarean section?  The answer to the first question is yes…sort of.  The first stage of labor (dilation of the cervix) actually has no significant difference in duration regardless of when an epidural is placed.  The second stage of labor (pushing and delivery of the baby) takes about 15 minutes longer on average with an epidural vs without.  That, too, makes sense as walking with feet that have fallen asleep is going to be a little slower going than on feet that aren’t a little numb.  As for increasing the risk of cesarean section, there is no apparent increased risk of cesarean section with epidural, although we do see slightly higher incidence of operative vaginal delivery, i.e. vacuum or forceps.

Can an epidural harm mom or baby?  More common side effects for mom can be nausea/vomiting, low blood pressure, itching and difficulty with urination.  While more severe effects such as infection and nerve damage are possible, they are fortunately very rare.  Backache or headache can also occur, but these are not expected to persist if they do.  Generally, sensation and ability to walk returns with a few hours after stopping an epidural.  As for effects on the baby, because the anesthesia is regional, we don’t expect it to cross the placenta into the baby’s blood supply.  Occasionally, we can see a decrease in blood flow to baby from mom if blood pressure gets to be very low, but if present, this is usually quickly corrected by treatment of mom’s blood pressure.  Otherwise, much like numbing a tooth for extraction doesn’t affect your toes, the effect on baby from epidural is expected to be rather minimal.
             
For some women, epidural anesthesia can be a very effective option for pain control during labor, delivery and any laceration repair (hopefully, you don’t have any vaginal tearing during labor, but if you do, numb is good!).  Other women either don’t need it or don’t want it.  I’ve had some moms say that better pain relief allowed them to be more in the moment and really enjoy their baby more, but others felt that abstaining from pain relief allowed them to be more present during labor.  Fortunately, unless there are medical reasons you can’t have an epidural, it’s a decision that you can make in conjunction with your OB and anesthesia providers.  Be sure to discuss with them any concerns that you may have, and also pay close attention to your anesthesia provider to clarify all of the risks, benefits, alternatives and indications prior to proceeding with any medical procedure.  Good luck with whatever decision is the right fit for you, and as always, we wish you your healthiest pregnancy, delivery and baby 😊

Dr. Nick

So, can laughing gas or nitrous oxide be used for labor pain?  Is it better than an epidural?  Does It work?  I get asked these questions all the time.  For most of us, our only experience with nitrous oxide is in the dentist’s chair.  If it works so well for dental procedures, can it work for labor?

Most expectant moms want some form of pain relief during labor.  However, some are really concerned about the lack of control and ability to move that comes with an epidural.  This is a valid concern.  Before epidurals, nitrous was used in the US and is still used in the UK, Australia, and Canada. 

So how does nitrous oxide work?  Nitrous oxide is a clear colorless gas.  It enters the blood by diffusion and is not metabolized by the body.  It is then eliminated by diffusion out of the lungs and therefore has its effect for roughly two minutes for on and offset.  This means when you inhale it, you will only feel the effects for about two minutes!  Nitrous oxide provides some pain relief but is mostly an anxiolytic (helps relieve anxiety).  It makes people feel euphoric and relaxed (You want to drill on my teeth, go for it, because I don’t care!).  This happy feeling is why it is called “laughing gas”.  It is usually administered with oxygen because there is a risk of death from lack of oxygen when used alone.   Side effects of nitrous include nausea, vomiting, headache, increased sleepiness and/or excessive sweating or shivering. 

So, what are the advantages of using nitrous to help control labor pain?  As the patient, you have a lot of control over when to use it (mask on, mask off).  It’s a lot cheaper than an epidural because it does not require the expertise of an anesthesiologist or a nurse anesthetist.  Anyone can show you how to breathe through the mask.  This may be why it is used so routinely in countries with socialized medicine.  It has a rapid onset of action and is easily reversible.   Lastly, (and possibly most importantly) it might make your doctor's jokes funny :)

So, what are the disadvantages of using nitrous to help control labor pain?

First of all, the effects of nitrous only last 2 minutes!  Can you imagine being in labor for 20 + hours and having to replace that mask every 2 minutes.  In addition, your caretakers would continuously be worried about your oxygen saturation.

Second, nitrous readily crosses the placenta and can have anesthetic effects on the fetus.  One of the main reasons so few labor and delivery wards offer nitrous as an option is because they need to have special equipment that can mix nitrous and oxygen.   The percent of nitrous you would receive at a dentist’s office is much higher than the nitrous you would receive in labor, hence it would be less effective.  If you received the same amount of nitrous in labor as you did in the dentist office this could easily cause hypoxia (oxygen level is too low for safety) in mom.  This could then easily cause fetal and newborn hypoxia, which is one of the most common causes of operative vaginal delivery or cesarean section. 

Nitrous is more sedating than an epidural.  It can also cause altered consciousness and impaired memory.  So, while you can move while inhaling nitrous, that may not be the safest option (kind of like we wouldn’t suggest driving drunk as it could cause a crash, walking while receiving nitrous gas could also lead to a crash for mom and baby).  That being said, it may make for some pretty incredible (and YouTube ready) labor and delivery videos!

Lastly, there are no great studies that look into the safety and efficacy of nitrous.  Most of the studies were not performed in the US, and of the ones that were, they did not include enough women or use standardized methods to provide reliable results.  One day nitrous may be a good option for pain control in labor.  However, first we need some better studies, especially ones that look into long term effects on the fetus, before offering it as a safe option for pain control.   

Dr. Pam