Monday, November 24, 2008

Special Topic: Death in Childbirth *long post*

Death during childbirth is an oft-used ploy in fiction. If done convincingly, it can add an intensity of tension, emotion, and tragedy to a story that few other events can, probably because the death of a mother and/or child is one of the most prevalent and deeply-held fears of our species. At the moment of miraculous life-giving, life is suddenly and unexpectedly ripped away.

So why is it that death in childbirth has become such a groaner in most fiction? The childbirth death scenes I have read revolve around the dramatic moment (often melodramatic) where the dying mother gasps out a name for her squalling, healthy infant with her last breath and timely expires. The likelihood of this scenario is so miserably small, not just in our modern society, but in every society across time, that it's frankly laughable to anyone who understands the birthing process.

But fiction is all about making the improbable seem plausible, so if death in childbirth interests you as a plot line, read on.

The Risks of Childbirth Today

In modern day US, maternal mortality - the measure how many women die during pregnancy, birth, or the postpartum period from problems related to childbearing, is 12.1 women in every hundred thousand. That's right, 12.1:100,000. Pretty sharp odds against. And remember, that's any woman who is pregnant, giving birth, or having given birth in the last 42 days. The number of women who actually die during the physical act of giving birth to a baby or soon enough afterward to gasp a name and promptly kick the bucket is minuscule in the extreme.

Non-developing nations, including parts of Africa, have much higher rates of maternal death, as high as 920:100,000 in the last 10 years. Reasons for this include lack of prenatal care, unsanitary conditions, lack of qualified, train professionals to oversee the pregnancy and birth, and poverty. Deaths occur for similar reasons as in developed countries.

What about the past?

Historically, maternal death rates have been higher than they are today. In 1915, the rate for US mothers was just over 600:100,000. Still pretty good odds of mom living through the process.

How does home birth fit into the picture?

That's a trickier question. The answer is, it depends on who you ask. Studies and papers published by MDs proudly proclaim that home birth is three times more likely to kill babies and mothers than hospital births. Studies done by non-medical affiliated groups and groups with vested interest in home birth show a maternal death rate that is much better than modern hospital births. Studies done in other countries, including studies of US births, report a remarkably low rate of maternal death when home births are attended by trained, licensed midwives. Those figures are consistent with home birth statistics in countries with much lower risks of maternal death than the US, like Sweden and Norway, where most births are attended by midwives and many are conducted in a home setting.

I'll leave it up to you to decide which to believe.

All research I could find on the subject agrees that unassisted childbirth or 'free childbirth' is extremely dangerous to mother and baby, with an exponentially higher risk for both.

Going to give mama the ax anyway? Here's how.

The biggest killers of women giving birth are blood loss, eclampsia (seizures from very high blood pressure), unsafe purposefully-induced abortion, obstructed labor, and sepsis (aka childbed fever). The graph below indicates the percent of total causes of maternal death worldwide and is provided by the NIH (National Institute of Health) based on data from the WHO (World Health Organization). Unsafe abortion is a topic for another day, but let's consider the other methods.



Blood loss, is generally going to kill much quicker than infection, for obvious reasons, but the tiny trickle of blood folks seem intent to pass off as 'bleeding to death' in childbirth is pretty funny. Pregnant women have a third more blood volume than non-pregnant humans. What's more, the end of pregnancy is the only time in the human life-span when someone can easily lose 30-40% of their total blood volume without going into shock and probably dying. That means a woman would have to lose liters of blood during the birth and shortly after, not counting the amniotic fluid which can dilute and falsely "pump up the volume" of blood being lost. And that's just for shock to set in.

Blood loss this significant is usually caused by:

  1. a baby that won't come out and let the uterus (womb) shrink back to it's normal size

  2. a uterus that is floppy and unable to contract after the baby and placenta (after-birth) are delivered

  3. the placenta is not expelled after the baby is born

  4. something completely unexpected, extremely rare, and oh-shit worthy happens.

Option 1 and you'd end up with dead mom, dead baby after probably 2 days of unsuccessful labor without a C-section. With C-section technology, this situation would likely not continue longer than 24 hours and they'd both be fine, barring surgical complications.

Option 2 has several quick solutions. Putting the baby to the breast will stimulate the uterus to contract as hormones called oxytocin flood the bloodstream. Oxytocin is a hormone that provides a dual function - contracting the uterus and releasing milk from the breasts. Another potential treatment in a modern setting is a "pit-drip" or an IV infusion of a drug called pitocin, which is a synthetic form of oxytocin. Finally, just giving the stomach a good, deep, firm massage will help get the lazy uterus to do it's job.

Option 3 can benefit from all the suggestions for Option 2, plus a possible surgery called a D&C, or dilation and curettage, which means the doctor opens up the cervix (part of the womb the baby exits through to the birth canal) and scrapes all the stuff on the inside of the womb out. This can be done with a relatively low level of technology, but using non-sterile instruments is a HUGE risk for infection, and there's also a slight risk of damaging the cervix to the point that the woman would miscarry any future pregnancies.

Option 4 would depend on why she's losing blood. Rupture of the uterus, part of the placenta covering the mouth of the uterus and preventing baby from leaving, abruption (where the placenta separates from the woman before the baby leaves the womb), or some other trauma would be best guesses for this factor. They are all pretty rare but usually require emergency c-section and surgery to correct the situation. They may end in hysterectomy (removal of the womb), but with a skilled surgeon on hand they are very survivable. A woman suffering one of these problems prior to modern medicine would probably not survive.

In any case, a modern setting is likely to have such life-savers as IV fluids, blood transfusions, and surgical intervention.

Sepsis, or infection was a big killer prior to the advent of antibiotics. Before the move of birth from the home setting to early hospitals in the last century the rate was still relatively low. Once birth moved to hospitals, with questionable sanitation and physicians who were practicing procedures on cadavers and then delivering babies without gloves or hand-washing, the infection rate soared. It remained high despite attempts to treat birth as "sterile" in the middle of the century. Today, a combination of infection control measures and antibiotics has significantly reduced the number of women who die from infection associated with pregnancy, but it still happens today.

The most common reasons for infection, today and in the past, have been unsanitary environments, non-sterile instruments like forceps or surgical tools, unwashed hands, shaving the pubic area, and prolonged labor that goes longer than 24 hours after the amniotic sac ruptures ("the water breaks"). The solutions for these seem pretty easy for the most part - work clean! Of course, in the era before germ theory and the knowledge that infection was spread by microscopic organisms, physicians didn't wash hands between patients. Why would they? As for the rupture of membranes, the solution for that is easy, too - deliver the baby. In a modern setting, this can be done by C-section, induction of labor (get it started) using a pit-drip or other medications. In a less tech-oriented society or among women who chose a more "natural" venue for birth, nipple stimulation, walking, certain foods, certain herbs (not recommended in modern times), and even sex can kick labor into gear.

The trouble with infection for the scenario that started this discussion is that it takes time to get septic (infection that is generalized throughout the body), usually 3-4 days before symptoms show up and a quick finale afterwards if they aren't treated promptly. Symptoms include high fever, chills, muscle aches, and foul-smelling drainage from the birth canal. This can progress to shock (low blood pressure), loss of consciousness, and death.

High Blood Pressure in pregnancy is called pre-eclampsia, which can lead to eclampsia. Eclampsia is life-threatening seizures caused by extremely high blood pressure. Signs of pre-eclampsia include swelling of the hands and face, dizziness, headaches, and changes in vision. The only cure for pre-eclampsia or eclampsia is delivery of the baby, but pre-eclampsia can be treated with medications to reduce blood pressure and medications called anticonvulsants can be used to prevent seizures

Obstructed labor, or the inability to push the baby out, can be caused by the position of the baby - breach (feet or butt down) or transverse (side-lying) are the most common positions that cause this. Other causes include weak contractions by the uterus, a very large baby, a very small pelvis in the mom, or a shoulder dystocia (shoulder gets wedged into position behind the pelvic bones). All of these require some intervention from a trained professional. In the case of a positional problem with the baby, a procedure called 'external version' can be done, in which the doctor or midwife uses hands on the outside of the belly to gently push the baby around in the fluid-filled womb until it's in the right position, which is head-down. External version is sometimes successful, but in most cases a C-section will be performed in modern times, and likewise a C-section is indicated for most other causes.

Again, obstructed labor can be a very dramatic event, both in the modern setting and in the historical/fantasy setting, but without prompt intervention, both mother and baby are likely to die, and with it, mom is not at significant risk, though if prolonged, baby can develop brain damage from lack of oxygen.

Summing it up

As you can see, death in childbirth isn't quite like the movies and books portray it. It can be just as heart-wrenching and dramatic, though, to have a mom die after several days of exhausting labor or a quick descent into infection. And if you have a near-miss planned, you now have a basis of information on the how, when, and why mom's die in childbirth. If you want more specific information not provided in this post, email me a question or try the following search terms:

  • Maternal mortality

  • Post-partum infection

  • Placental abruption

  • Placenta previa

  • Shoulder dystocia

  • Cephalopelvic dysproportion

  • Cesarean section

  • Home birth

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Monday, June 30, 2008

How premature does a baby have to be to have trouble breathing?

Any baby can have trouble breathing after birth, regardless of prematurity or size, but breathing problems are much more common in babies who are very early, very small and underdeveloped, or very large. Some common reasons for respiratory distress syndrome (breathing trouble requiring oxygen or other support) in newborns include:




  • Prematurity - lungs are underdeveloped. Typical pregnancies last 38-42 weeks gestation (how long the baby is cooking from the mother's last menstrual period). Respiratory distress syndrome is generally mild to moderate from 34-37 weeks in healthy babies and becomes increasingly severe if the baby comes earlier. Babies less than 28 weeks very often require special medication delivered right into their lungs call Surfactant, to help keep their lungs from collapsing between breaths.
  • Infection - infection in the mother can be passed to the baby. Babies who have respiratory distress that lasts more than a few hours or is severe at or shortly after birth are generally screened for infection (also known as sepsis) and given 48 hour courses of Gentamicin and Ampicillin (antibiotics) even if no infection is identified. Because of immature immune systems, even if the baby has no outward signs of infection other than respiratory distress and the cultures come back negative, the baby could still have a hidden infection.
  • Heart and circulatory defects - there are many kinds of heart defects and circulatory problems that can result in poor perfusion to the lungs or to the body, resulting eventually in breathing problems. Some heart problems don't cause noticeable problems until the baby's body starts to accommodate to life outside the womb by closing down special circulatory pathways that the fetus needs, but a breathing baby doesn't. This can take several hours or even days.
  • Diabetic mothers - these babies are usually very large - >9lb at birth and can be very large even if born early. Because of mother's chronic high blood sugar, baby doesn't develop in quite the pattern expected and can suffer respiratory distress, low blood sugars soon after birth, heart problems, and multiple birth defects, particularly if the diabetes was poorly controlled during the pregnancy. Gestational diabetes - a form that goes away after the baby's birth, can cause the same problems.
  • Anatomical defects - certain birth defects which are rare but can cause severe respiratory distress include anything that prevents the lungs from fully forming or expanding, anything that impairs circulation, brain or brain stem malformations, and anything that causes severe pain or nervous system irritability.





A photo of acrocyanotic feet. Acrocyanotic means a bluish tinge on the periphery of the body - the hands and feet. Notice the purplish heels especially

And since this is for writing and I'm assuming you'll be describing the scene and the problems, here's a quick rundown on how a normal respiratory effort looks and some of the trouble signs:

  • Respiratory rate 30-60 breaths per minute - too fast or too slow can be bad. As a nurse, I'd rather see too fast than to slow, though. Breathing too slow (or not at all) is an ominous sign of trouble.
  • No grunting noises - babies in distress often make a little grunting sound at the end of each breath. The reason for this is they are trying to keep a little pressure in their lungs at the end of the breath, to keep their lungs from collapsing. It's imperative that lungs stay slightly open after a breath, because lungs that are completely closed require many times as much effort to open back up.
  • No nasal flaring - The sides of their noses will flare out if they are trying hard to get more oxygen. Think of someone you've seen about to launch into a tirade and how their noses widen a bit as they get their breath to blow like Mount Vesuvius.
  • No head bobbing - Babies in distress will bob their heads with each breath in an effort to open the airways wider to breath in and narrow them down a bit when breathing out.
  • Breath sounds clear and equal - breath sounds may sound a little "wet" or crackly in some babies, particularly if born by C-section as there isn't a lot of squeezing to get that excess water out of the lungs like a vaginal birth. If the breath sounds are decreased or absent on one side, this could indicate that the baby has a collapsed lung, or is having a problem called pnuemothorax, which means baby has developed a hole in the lung which allows air to collect in the cavity between the lung and the chest wall, compressing the lung more and more with each breath and not allowing it to re-expand. This can lead to a life-threatening condition known as "tension pneumo" in which so much air has built up in the chest cavity that it is pushing everything over - the lungs and eventually the heart - and pressing so hard it's decreasing circulation. Pneumothorax and tension pneumos are treated by inserting a "chest tube" into the chest cavity that allows the air to be slowly pulled back out and gives room for the lung to re-expand and heal
  • No central cyanosis (blue tinge around face, lips, or the center of the body). It's ok for baby's hands and feet to be blue or purplish for the first 24-48 hours, but an overall pink color (pink as in a healthy coloring, not as in salmon or caucasian) is preferred. Babies with very dark skin can be assessed by looking at lips and tongue - if those are pink, no worries

Treatment for respiratory distress in the newborn is pretty organized. If breathing, baby would first be given oxygen either by nasal cannula (see photo at right), by "blow-by" which means blowing oxygen across the baby's face, or by face mask. If that doesn't work, hand-bagging would start, which means using a mask and bag with a special valve to force air into the baby's lungs. A baby being hand-bagged will quickly be intubated (have a small plastic tube inserted past the vocal cords and into the lungs) and would either continue to be bagged through the tube or be hooked up to a ventillator. Deep suctioning through the breathing tube is likely to occur and Surfactant may be given to help the baby keep the lungs open between breaths. Unless the lungs are seriously malformed, this is usually sufficient. In some very rare cases, if the baby was born at a fetal care center or a center that was prepared for an unusual defect, a baby unable to be helped by hand-bagging or ventillator might be put on ECMO which is a long-term (up to 3 weeks, sometimes) heart-lung bi-pass machine. This has MANY risks and about a 50% chance of survival, depending on the reason it is used.



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