Most of us associate nitrous oxide with dental work, but it can also be used to relieve the pain of childbirth. While four hospitals in Vermont offer nitrous oxide in their birthing center, and others are contemplating it, the University of Vermont Medical Center is not on board.
Nitrous oxide, otherwise known by its nickname "laughing gas," has been used as pain relief for more than a hundred years throughout the world.
Copley Hospital in Morrisville is one of four hospitals in the state that has recently begun to offer nitrous oxide in their birthing center. The hospital sits on a quiet rural road, a cornfield and cemetery among its closest neighbors, with snow-covered Elmore Mountain as its backdrop. About 200 babies a year are born at this small, two-story community hospital.
A couple of years ago, when the nurses and midwives at the birthing center heard that Northeastern Vermont Regional Hospital in St. Johnsbury was using nitrous oxide for their laboring women — the first in the state to do so — the Copley staff was thrilled.
Although nitrous oxide has been around for many decades and used regularly in various countries with top-tier health care — such as Canada, Australia and Finland — it had fallen out of favor in the United States with the advent of the epidural in the 1970s.
In 2011, there began a resurgence of the gas in the U.S., mostly initiated by nurses and midwives. Today, nitrous oxide is offered in more than 400 hospitals and birthing centers across the country and the list grows longer each year.
"People are enthusiastic. I think they like the idea that it doesn't have a lot of side effects, it doesn't need an IV, it doesn't take a long time to wear off, it can be used anytime in the labor." — Kipp Bovey, certified nurse midwife at Copley Hospital
The Copley team was excited to provide another option for pain relief, besides an epidural, for their low-risk population — something that would allow them to remain mobile during labor. They hand out an information sheet from the American College of Nurse-Midwives at prenatal appointments.
“People are enthusiastic,” says Kipp Bovey, a certified nurse midwife at Copley. “I think they like the idea that it doesn’t have a lot of side effects, it doesn’t need an IV, it doesn’t take a long time to wear off, it can be used anytime in the labor.”
Bovey points to the machine in the corner of the room that blends and dispenses 50 percent nitrous oxide with 50 percent oxygen – different than in dental work, where it can be a mix of up to 70 or 80 percent nitrous oxide.
The machine, called PRO-NOX, is manufactured by a company called CAREstream in Florida. Typically, these small compact mobile units sell for about $13,000.
It is billed by the hospital as part of the birth, not separately, and can be as low as 15 cents per use. The patient breathes in the mixture of nitrous oxide and oxygen through a mask or mouthpiece. The woman must hold her own mask, so she decides when and how much to use it.
“It’s usually we have them start breathing 30 seconds before we anticipate the next contraction starting. You get a few good breaths, try to keep breathing in through the tube as long as you can during the contraction,” says Bovey.
Someone must be in the room with the mother while she is using it, but it doesn’t have to be a staff member.
Kelly Locke was 10 days overdue with her son, Russell, when her water broke and she headed to Copley from her home in Johnson, about 20 minutes away. After many hours of labor, Locke wanted something to take the edge off, ease her anxiety and help her get through the rest of the labor.
Locke chose to use nitrous oxide so she could still move around and be active in her birth. She had already heard about it in her birthing class and was intrigued; it appealed to her as an alternative to an epidural or IV narcotic.
“I didn’t want to be confined to a bed. I also wonder if with my contractions stopping when I was lying down — I mean that happened during my entire birth — if I had had an epidural, would my birth have gone differently? Would I have had to have [a] C-section?” says Locke. “So I really feel thankful that I didn’t have to explore that, and I wanted to experience all of my birth.”
Nitrous oxide is just another option, although not for everyone; some women don’t care for it, says Bovey.
Bovey says Copley’s use of nitrous varies month to month, anywhere from 15 percent to 57 percent of patients use it in a given month — and not only during labor, but also postpartum.
Besides Northeastern Vermont Regional and Copley hospitals, Brattleboro Memorial and North Country hospitals both also offer the use of nitrous oxide for women in labor.
Gifford Medical Center, Southwestern Vermont Medical Center and Northwestern Medical Center are looking into it or hoping to get it soon. Central Vermont Medical Center is in the process of getting it.
When Kelly Locke toured the University of Vermont Medical Center, she was told nitrous oxide was not an option and that if she wanted something besides an epidural for pain relief, there was IV narcotics. Locke says she chose Copley over UVM because of the option for nitrous oxide.
Marti Churchill, a certified nurse midwife at the University of Vermont Medical Center, would love to see nitrous oxide as an option for her patients.
“As a midwifery practice we have really wanted to see nitrous oxide be available, but the administration in the anesthesia department is really not open to that and hasn’t been for quite some time,” says Churchill.
"As a midwifery practice we have really wanted to see nitrous oxide be available, but the administration in the anesthesia department is really not open to that and hasn’t been for quite some time." — Marti Churchill, certified nurse midwife at UVM Medical Center
So why the resistance at Vermont's largest hospital?
“I think it’s great in smaller hospitals where they have very healthy patients and they have a very low volume,” says Dr. Lydia Grondin, director of obstetric anesthesia at the UVM Medical Center. “However in a place like this, where we're doing a lot of deliveries, our nurses are going to have a lot of exposure to the nitrous oxide and the long-term exposure can cause significant medical issues for people.”
The medical issues she refers to are possible problems metabolizing vitamin B12, bone marrow deficiency and anemia. The National Institute for Occupational Safety and Health (NIOSH) recommends the levels of nitrous oxide in the room stay below 25 parts per million.
When asked about concern for her and her staff's exposure to nitrous oxide and its potential harmful long-term effects, Kipp Bovey says the machine they have at Copley takes care of that.
“The unit that we have has a scavenger system, so the mom has to breathe in and out through the mouthpiece or the mask, and then it suctions up the exhale and sends it up the suction system in the room so we hook it up to the wall suction," Bovey explains.
Furthermore, Marti Churchill of UVM Medical Center says, there are ways to make sure exposure is kept to a minimum. Many staff members at other hospitals use dosimetry badges to measure the ambient level of nitrous oxide in the room, ensuring it stays below industry standards.
“There is a dosimetry badge that people can wear so they make sure that they have less than 25 parts per million, and if a woman is educated on how to use the apparatus, it has scavenging to draw in the extra nitrous oxide and very little is emitted into the atmosphere in the room,” Churchill says.
Besides, adds Churchill, the U.K. and many countries in Europe, as well as Australia, have been using nitrous oxide for decades and there haven’t been any issues. If a patient is educated to use the machine properly, says Churchill, it works well.
"I think it’s great in smaller hospitals where they have very healthy patients and they have a very low volume. However in a place like this [UVM Medical Center], where we're doing a lot of deliveries, our nurses are going to have a lot of exposure to the nitrous oxide and the long-term exposure can cause significant medical issues for people." — Dr. Lydia Grondin, director of obstetric anesthesia at the UVM Medical Center.
But Grondin, also with UVM Medical Center, is not taking any chances.
She claims the manufacturing companies making these nitrous oxide units are doing a great job marketing them and it’s not all good. Dartmouth-Hitchcock Medical Center stopped using nitrous oxide about five years ago, not long after they started using it, Grondin says, due to the high level of exposure to the staff in the delivery rooms.
“The PRO-NOX was actually one of the ones studied by Dartmouth and in one grouping of their patients they had a 70 percent over NIOSH standard for the staff member in the room, and the reason for that is one breath out doesn’t get rid of all the nitrous oxide. Nitrous oxide goes into the bloodstream and then it comes out of the bloodstream unchanged. So it will continuously be breathed out because you don’t breathe it all out at once,” Grondin says.
While the UVM Medical Center does not have a policy against using nitrous oxide in labor — and in fact, some of its affiliated hospitals do offer it — Grondin and a few colleagues in the obstetric anesthesia department feel strongly against its use.
While one of Grondin's concerns is staff exposure due to the high volume of deliveries, other large university medical centers with similar or much higher delivery rates than UVM — such as Stanford, Yale and Vanderbilt — use nitrous oxide in their labor rooms without this concern.
The staff at Vanderbilt University Medical Center wear dosimetry badges that regularly report less than 2 parts per million during use. At Yale, they monitor the gas as a closed system, like that of Copley, with the scavenger hose suction attached to the wall.
Michelle Collins, a professor of nursing and certified nurse midwife at Vanderbilt University Medical Center, has written numerous scholarly articles about the safety and benefits of nitrous oxide for laboring women.
Collins claims that the low concentration of nitrous oxide, the intermittent flow and the 50-50 mixture of oxygen and nitrous oxide make it a safe option for women, staff and baby.
Hospitals are businesses too, and some proponents of nitrous oxide have pointed out that it could be an issue of money — especially since anesthesiologists make high salaries.
If a woman chooses an epidural, it does make more money for a hospital. For example, at Copley, a typical labor without an epidural costs somewhere between $3,000 and $5,000. With an epidural, the cost is in the range of $5,000 to $8,000.
But if money were at the root of UVM’s reluctance to offer nitrous oxide, the statistics don’t back that up. At hospitals where it is offered, the epidural rates have stayed the same; epidural rates have not decreased since the introduction of nitrous oxide at Copley hospital, according to Kipp Bovey.
Aside from her concerns over staff exposure, Dr. Lydia Grondin has another reason she won’t use nitrous oxide.
“It is a terrible environmental pollutant. This new trend of using nitrous oxide is very disturbing to me. It stays in the ozone for 114 years,” she says.
"It is a terrible environmental pollutant. This new trend of using nitrous oxide is very disturbing to me. It stays in the ozone for 114 years." — Dr. Lydia Grondin
But Marti Churchill finds this argument unconvincing.
“The amount of nitrous oxide that causes the terrible greenhouse gas side effects really comes from our farming industry and all the nitrogen that's poured into the oceans and into our soil, and so that’s by far much higher levels than would come from a laboring woman,” says Churchill.
According to the Environmental Protection Agency, 75 percent of nitrous oxide emissions come from agricultural soil management.
Still, Grondin claims that using nitrous oxide is akin to driving your car to Florida and back. She is not willing to add more pollutants to the environment.
Vanderbilt’s Michelle Collins says “compared to other source of environmental pollutants, it’s a fraction of a fraction.”
"The amount of nitrous oxide that causes the terrible greenhouse gas side effects really comes from our farming industry and all the nitrogen that's poured into the oceans and into our soil, and so that's by far much higher levels than would come from a laboring woman." — Marti Churchill
The mixture of 50 percent nitrous oxide and 50 percent oxygen renders the medication an analgesic and not an anesthetic, its potency lessened by the oxygen and only 20 to 30 percent effective as pain relief anyway.
But that’s why nurses and patients like it. Unlike a narcotic that can make you sleepy and crosses into the placenta, and unlike an epidural that tethers a woman to her bed, nitrous oxide is an alternative, sometimes before an epidural, sometimes instead of, but ultimately putting more control in the hands — literally — of the woman herself. That’s the goal of offering nitrous oxide.
This is the main reason why Kelly Locke chose to give birth at Copley Hospital instead of UVM Medical Center. She wanted another option for pain relief and for her, nitrous oxide felt like an empowering choice.
Amelie Thurston, the nurse educator at UVM, and Dr. Grondin don’t disagree with this. They just want to use something that is safe for everyone involved. Is nitrous oxide it? Grondin says the research and possibly the answers to this question are about five years out.
“All the studies that have been on the volatile agents now they are just taking them and doing them for nitrous oxide. Because it had fallen out of favor, nobody thought to take a look at it," Grondin says. "Now that there’s a resurgence, people are like: 'Oh, wait. You know, we know this about volatile agents — what if this is happening with nitrous oxide? We need to take a look at this.'”
In the meantime, Locke is grateful nitrous oxide was an option for her.
Jessica Lara Ticktin is a freelance writer and childbirth educator who lives in Burlington with her husband and their four children.
Disclosure: Copley Health Systems is a VPR underwriter.
