How Birth Simulators Work

Medical simulators in general are nothing new. Most of us have seen a synthetic (or perhaps real) skeleton in a classroom setting, or replicas of various body parts in a doctor's office that show how the human body works. These models are great educational tools for teaching anatomy, but they can't prepare a student for the reality of the delivery room.

One of the first modern birth simulators came about in 1949. During the aftermath of World War II, a military surgeon "recognized how polymers used in reconstructive and battlefield surgery could be used to create simulators for health care education," and a new teaching methodology was born [source: Gaumard]. Early simulators weren't much more than a rubber model of a woman's anatomy. Over the years, they gradually increased in complexity as technology advanced. The miniaturization of electronics and computer chips allowed developers to take simulators to a whole new level of realism.

In the 1990s, these digital delivery systems came to be called robot birth simulators. By 2000, Gaumard Scientific, which pioneered the original birth simulator, introduced one of the most popular simulators on the market: Noelle. In 2011, Noelle cost anywhere from $2,000 for a simple model to more than $60,000 for a fully-loaded, sophisticated robot. While that may seem expensive, Noelle can simulate a wide variety of childbirth complications that a student would normally only encounter in real-world situations where lack of experience can be a significant handicap.

In 2005, another high-end contender in the simulator arena arrived in the form of BirthSIM, produced by Laboratoire Ampère in Lyon, France. While comparable in price to the tricked-out Noelle, BirthSIM focuses entirely on educating medical personnel in the proper use of forceps. For the price, you might think it would or should do more, but improper use of forceps can cause serious, permanent and potentially fatal damage to a baby during delivery. BirthSIM combines real forceps with a virtual imaging system to help obstetricians get invaluable practice.

Not all birth simulators are high-tech and expensive. Some simulators cost only a few hundred dollars and can be useful for relatively simple simulations. Most of these table-top models replicate basic birthing scenarios and can't be adapted to challenge students with surprise complications the way a simulator like Noelle can.

At this point, it's worth taking a closer look at the status of birth simulators in medical education.

Medical schools all over the world are educating students with birth simulators like Noelle, and more schools are making the investment in sophisticated simulators to round out their training programs [source: Elias]. These powerful robots don't come cheap. Are they worth the money?

Britt Guerrero, a practicing ARNP (Advanced Registered Nurse Practitioner), worked in the training laboratory at the University of Alabama-Birmingham, and says these simulators are "very critical" to the training of obstetricians and related medical personnel, including nurse mid-wives. Other studies back her up, citing staff and student surveys regarding how valuable they believe the simulator training was based on their experience [source: Davis].

A common complaint, though, is that empirical research on the cost-effectiveness of sophisticated robotic birth simulators is lagging behind their use. In fact, one research study implied there was no significant difference in the overall amount of learning between a control group without simulator access and one training on simulators [source: Reynolds].

Still, it's hard to argue that using a birth simulator isn't helpful; practice makes perfect, right? So while the jury may be out regarding hard data, most medical schools consider the cost of simulators worth the increased safety of mother and child, especially when so many other competing schools are utilizing the technology.

This also raises the question of just how closely simulators mimic the real thing. Let's pull back the gown and see what makes these robots tick.

Birth simulators today are highly sophisticated machines, capable of throwing a host of potential complications at unsuspecting trainees. Noelle is a full-size mannequin, complete with all of the limbs and joint articulation of a real woman. Noelle is controlled wirelessly via a computer with a proprietary interface. The technician piloting the training scenario is normally in a separate room up to 100 meters (300 feet) away from Noelle and her student caregivers. Training leaders can create their own birthing scenarios, and change them on the fly from the controller. The prenatal robot comes with pre-programmed sounds, but has a streaming audio option to allow a live person to speak as the voice of Noelle.

Under Noelle's skin, mechanical motion-control devices called actuators simulate contractions, convulsions and other abdominal movements, though her arms and legs are immobile. She can't squeeze a husband's hand with a crushing grip, but Noelle's eyes do dilate, and so does her cervix. Even her chest rises and falls as she breathes.

Heart rate and airway sounds are important diagnostic measurements and are a big part of the simulation. The simulated heartbeats register on real ECG monitors. Noelle's blood pressure can be monitored, but requires a special device from Gaumard rather than the methods used with real women, since there is no actual blood coursing through her veins.

Noelle's baby comes complete with umbilical cord and is held in place by a mechanism that sends the bouncing baby 'bot down the birth canal at the time of the programmer's choosing. The baby can be delivered via vaginal birth or C-section and can be oriented into positions for a vertex (head first) delivery or a breech (butt first) delivery. The baby also simulates breathing sounds and heartbeats, and its vital signs can all be monitored using the same equipment you would use on a real baby.

A lot of electronic equipment goes into this robotic simulator, so while monitoring amniotic fluid is an important part of training, any moisture has to be handled carefully so it doesn't damage and of the simulator's components. Noelle simulates hemorrhaging using fake blood, but a full water release isn't possible yet.

We mentioned complications earlier, and here is where Noelle truly offers students a unique opportunity to experience scenarios that would be extremely dangerous and stressful in real-life situations. Noelle can reproduce a wide range of complications and even a combination of problems, like shoulder dystocia (the infant's shoulder becomes lodged behind its mother's pubic bone after the head has already exited the birth canal) and a heart attack. Because she has no tether and has self-contained functions, Noelle can even be used to replicate trauma scenario births, like accident-induced labor and delivery.

By practicing complicated delivery situations in the safety of a simulation scenario, medical staff can be much more prepared when they are faced with those same complications with actual patients. Next, let's look at how those simulations play out.

So, just how do students interact with Noelle? Britt Guerrero, ARNP walked us through a typical teaching situation:

This is just one scenario. There are literally thousands of potential versions of the birth, based on how the simulation began and what elements are introduced by the instructor. Throughout the delivery exercise, conductive skin on the robotic mother and child gives realistic feedback to students via the same equipment they would use on real patients, adding a high degree of realism to the proceedings.

At each step of the process, the instructor decides if the students are handling the situation properly, and adjusts the simulation accordingly. The protocols instructors use for these simulations are developed around guidelines set forth by AWHONN (Association of Women's Health, Obstetric and Neonatal Nurses) and ACOG (American Congress of Obstetricians and Gynecologists). The school or hospital where the simulation is being performed also establishes guidelines for simulations exercises based on its curriculum. Each simulation is tracked and documented so instructors and students can review the patient file once delivery is complete.

It's clear that birth simulators add an extra dimension to the training of obstetrics personnel. New software and hardware is always being developed to more accurately replicate human deliveries in order to increase practitioner knowledge and, in turn, patient safety. Eventually, robotic simulators will likely be equipped with a full complement of bodily fluids, multiple-birth options and the ability to give emotional feedback.