The Dangers of Epidurals, and the Surprising Problem with Research on Childbirth Anesthesia

From Lise Eliot's What's Going on in There: How the Brain and Mind Develop in the First Five Years of Life confirms my worries. Here are a few of her concerns:

• Every drug used for epidural anesthesia can diffuse out of the epidural space and enter the baby’s circulation. The good news…is that the total amount of drug reaching the baby is considerably lower than in systemic administration. Nonetheless, whatever dose does enter the mother’s bloodstream crosses quite efficiently to the baby’s circulation.

• Although many studies report no effect…on Apgar scores or cursory neurological exams, few of them have used wholly unmedicated mothers as a control group. Using more sensitive indices of infant behavior, some studies have found that newborns…are less alert, less able to orient toward stimuli, and less mature in their motor abilities than babies of unmedicated mothers. Greater exposure…makes babies jumpy and more irritable. The effects are most pronounced on the first day after birth, but some have been found to persist up to six weeks of life.

 

• The most common side effect of epidural administration is…a reduction in the mother’s blood pressure. Maternal hypotension is at least partially responsible for the fact that the baby’s heart rate often slows down for a while shortly after an epidural anesthetic is injected. If the mother’s blood pressure falls too low for too long, it can seriously compromise blood flow to the placenta, reducing the fetus’s supply of oxygen. These serious side effects are prevented by giving the woman fluids through an IV….If this countermeasure doesn’t work, another drug may be needed to prevent her blood pressure from falling too low and compromising the baby.

• Many studies have now shown that women who receive epidurals have longer labors, on average, than women receiving systemic analgesia. This is especially the case during the pushing phase…. Women receiving epidurals are more frequently diagnosed with dystocia, the failure of labor to progress, four times likelier to require forceps, and two or three times likelier to end up having a C-section, than women receiving systemic analgesia or no pain relief.

 

• Although most babies are not significantly affected, epidural anesthesia may compromise the health of the small subset of babies already at risk due to illness, prematurity, or a difficult delivery. Encouraging more women to have unmedicated deliveries would be better for babies, and for the women themselves, who would be exposed to fewer side effects, have shorter labors, and might be in better shape to begin breast-feeding and bonding with their babies right after delivery.

None of these concerns surprised me. What I did find astonishing was her report of the difficulty in getting reliable data on the adverse effects of epidural anesthesia relative to no anesthesia at all, instead of relative to other forms of pain relief: “There are simply too few ‘natural’ deliveries to enroll in a clinical study!” Upon reflection, I believe there are more mothers who chose unmedicated delivery than she implies, though I’m also certain the numbers are far lower than they would be if the public were better educated about the joys of natural childbirth and the dangers of anesthesia. Two additional reasons come to mind for the lower numbers available for study: Those who chose natural childbirth often do so for reasons that would also make them reluctant to have their newborns’ lives disrupted by clinical study. And, sadly, the hostile atmosphere frequently encountered by those seeking to avoid unnecessary medical interventions in the births of their babies often drives them underground, where they avoid observation for good as well as ill.

Epidurals and Pain Relief

For the most part, epidural analgesia does effectively relieve labor pain.1 Obstetrical anesthesiologists continue to state that epidural analgesia has other, potentially catastrophic, adverse effects but, with safe clinical practice, these problems are extremely rare. We will suggest in the material that follows that these complications are not extremely rare, and that women are not receiving adequate informed consent about what these complications are and their accompanying frequency. Nor are they being offered any serious alternatives to epidural anesthesia. Despite this, anesthesiologists such as Eberle and Norris argue that specific anaesthetic techniques ... or obstetrical management can limit or eliminate these risks of epidural labour analgesia. What must be remembered for any technical procedure, is that it is studied in major academic centers where highly skilled professors supervise residents and all outcomes are monitored closely. The actual practice, however, takes place in smaller institutions by less qualified individuals so that the actual complication rates of any procedure (obstetric, cardiac, pulmonary) are always higher than what are found in studies.
[Return to "Quick-Index of the Medical Risks of Epidural Anesthesia"]

Myth: Natural childbirth makes about as much sense as natural dentistry and epidurais are the Cadillac of anesthesia.

Reality: "Reported maternal complications of epidural analgesia include: dural puncture; hypotension; . . . increased use of operative delivery; neurological complications; bladder dysfunction; headache; backache; toxic drug reactions; respiratory insufficiency; and even maternal death. The fetus may also suffer complications as a result of maternal effects (for example, hypotenston) or direct drug toxicity."
Simkin and Dickersin 1989

"Planning Your Childbirth," a brochure put out by the American Society of Anesthesiologists (ASA), encapsulates the mainstream medical viewpoint on epidural anesthesia. Equating it with "pleasant, safe, and comfortable," the brochure begins by inverting the meaning of natural childbirth:
Today's mothers are reconsidering the idea that childbirth is "natural" only without medication, and they are choosing to have pain relief. . . to help them experience a more comfortable birth.

It misrepresents the effect on labor:
Will it slow down my labor? Some may have a brief period of decreased uterine contractions. Many . . . are pleasantly surprised to learn that after the epidural. .. [has] made them more comfortable and relaxed, their labor may actually progress faster.

Can I "push" when needed? Epidural analgesia allows you to rest during the most strenuous part of labor. . . . [W]hen it is time to push . . . [t]he epidural block can reduce your pain while allowing you to push when needed.
It glosses over the risks of epidurals:
Will the epidural block affect my baby? Considerable research has proven that epidural . . . anesthesia can be safe for both mother or baby. However, special skills, precautions, judgements and treatments are required.

What are the risks . . . ? [C]omplications or side effects can occur even though you are monitored carefully and your anesthesiologist takes special precautions to avoid them. To help prevent a decrease in blood pressure . . . [etc.]. By holding as still as possible during the needle placement, you help to decrease the likelihood of a headache [so it is her fault!]. The discomfort, sometimes lasting a few days, often can be reduced or eliminated by simple measures. [T]he anesthetic . . . may . . . affect the chest muscles and make it seem harder to breathe. Sometimes oxygen might be given to relieve this feeling and help the breathing. . . . To help avoid unusual reactions [stemming from injecting the medication into a vein], your anesthesiologist will administer a test dose.

They tell no lies, but they sure skate around the truth.

If an epidural is a Cadillac, it is a used one with concealed defects. The risks of epidurals convert normal labor to a high-tech event. An IV must be started to help counteract the tendency of epidurals to cause hypotension. Electronic fetal monitoring (EFM) is necessary because epidurals can cause fetal distress, and the mother's vital signs must be closely monitored to warn of maternal adverse reactions. If the needle or catheter pierces a blood vessel, which is easy to do in pregnancy because blood vessels are enlarged (Corke and Spielman 1985, abstracted below), or the needle goes deeper than the epidural space, convulsions, respiratory paralysis, and/or cardiac arrest can occur. Tests are done to confirm proper placement before giving the full dosage, but these are not completely preventative. Trained personnel, resuscitation equipment, and medication must be immediately available.

In labor, epidurals increase the need for oxytocin, instrumental delivery, episiotomy, and bladder catheterization. The first-time mother is more likely to have a cesarean. Temporary postpartum complications include urinary incontinence, nerve injury causing muscle weakness or abnormal sensation, and headache, which can last for days and is excruciatingly painful. Instrumental delivery and episiotomy increase the probability of deep perineal tears, which can have long-term effects on sexual satisfacfion and fecal continence (see Chapter 14). Backache and headache may become chronic. In the newborn, epidurals may cause jaundice, and there may be adverse behavioral effects. Finally, no one is collecting figures, but having an epidural must add considerably to the cost of the birth.
Recent innovations have not helped. Even when the dosage was so small that many women could walk despite the epidural, cesarean rates were not reduced (Oriol 1992).

Within the past decade, epidurals went from being reserved for particularly prolonged or difficult labors or cesarean sections - when they are, indeed, a godsend - to the norm at American deliveries. An overwhelming number of doctors and an increasing number of nurses think epidurals should be routine. Why should any woman suffer in this day and age? they ask. Their patients have bought this, making epidurals all but universal at many hospitals.

To reach this point, doctors swept the dark side of epidurals under the rug (Brownridge 1991; Reynolds 1989; Richardson 1988; Cheek and Gutsche 1987, abstracted below; Clark 1985). They attributed life-threatening complications to poor technique. And if nobody made any errors, well, complications occurred rarely, and if handled right, mother and baby were almost always fine. They denied that epidurals lead to other interventions and that these interventions introduce risks. Or if they did not deny it, they did not see intervention rates as a problem. They also dismissed adverse effects on the baby as either nonexistent or too insignificant to worry about.

Labor pain became not only something to be blotted out, but in a stunning reversal, the pain, not epidurals became the danger. The mother's stress hormones are accused of causing fetal distress. Women who do not want an epidural are portrayed as masochistic, misguided, or misinformed, even, by virtue of this last twist, uncaring of their baby's welfare (Brownridge 1991; Reynolds 1989).

Does it make sense to tell women to avoid even a single glass of wine during pregnancy and then push drugs during labor? This contradiction is one tipoff that attitudes toward epidurals are culturally determined beliefs masquerading as objective truths. Inversions of this kind are rife in the popular press on epidurals, as well as in the medical literature. As examples, in a newspaper article, a psychologist and an anesthesiologist denounce childbirth educators for leading women to think they can cope with labor pain unaided by drugs and for telling them epidurals have risks (San Jose Mercury News 1993). These same experts describe the guilt, anger, and sense of failure (even to feeling suicidal) women experience after they ultimately "require" an epidural. Epidurals are safe, they contend, but labor pain and attempting natural childbirth are hazardous to psychological health. The ASA brochure warns in oversized uppercase letters not to eat or drink after labor begins. Epidurals are safe, even part of natural childbirth, but quenching thirst and eating during hours of strenuous activity are dangerous.  WHY?  Because they know you are probably headed to the Operating Room for a C-section!

The need to make reality match belief leads to considerable distortion of the facts and prevents a rational evaluation of the risks and benefits. For example, Cheek and Gutsche (1987), as do others, recommend epidural block to protect high-risk fetuses from the dangers of maternal stress response to labor pain, shortly after they say a maternal drop in blood pressure is "the most common side effect" of epidurals and warn that a compromised fetus may not tolerate even a 15% to 20% fall in maternal pressure.

Another tipoff is the attitude toward those who do not conform. Cultural norms are traditionally enforced by exerting pressure through ridicule or scorn. Most women with mainstream medical care who make an effort to resist epidurals will find this out for themselves.

In fact, the pain and stress of normal labor have value. The stress hormones produced in response to labor, adrenaline and noradrenaline, trigger the final preparation of the fetal lungs to breathe air, mobilize fuel for energy, and, by shunting fetal blood away from the extremities and to the brain and heart (exactly opposite of the effect in adults), protect the fetus against hypoxia (oxygen lack) during labor (Lagercrantz and Slotkin 1986).

Nerves in the cervix, and later the pelvic floor muscles and vagina, transmit stretching sensations as well as pain. These stretch receptors signal the pituitary to produce more oxytocin, which increases the tempo of the labor, causing further cervical dilation. Once the cervix is completely open and the head distends the pelvic floor and vagina, surges of oxytocin are produced, creating the urge to push. Numb the nerves with an epidural, and you also wipe out the positive feedback mechanism (Johnson and Everitt 1988; Bates et al. 1985; Goodfellow et al. 1983).

Pain guides the mother. Commonly, the positions and activities she chooses for comfort are also those that promote good labor progress or help shift the baby into the right position for birth. Remove the pain, and you kill that feed back mechanism too.

The pro-epiduralists see the mother as needing rescue, but in reality her body prepares her to meet labor's challenge. Stress hormones give her stamina. By the time of the birth, endorphins, the body's natural painkillers, are found at levels 30 times higher than in nonpregnant women, and levels can be 20 times higher in women with prolonged or difficult labors as in uncomplicated labors (Jimenez 1988). Endorphins, produced in response to pain and stress, are also mood elevators. They are responsible, for example, for "runner's high." Oxytocin has mood-elevating and amnesiac properties too (Fuchs 1990).

Unlike epidurals, natural childbirth strategies facilitate labor both physiologically and psychologically. They raise endorphin levels, whereas epidurals reduce them (Jimenez 1988). They give the mother knowledge, skills, and confidence. Studies show that the key to a positive labor experience is mastery - a sense of control over events. With an epidural, control is completely given over to medical staff (Simkin 1991; Humenick 1981; Humenick and Bugen 1981).

While the normal stress of labor is beneficial, extreme anxiety or fear may have adverse effects (Simkin 1986). However, this type of stress may be extrinsic to labor. The animal studies that reported that stress in labor caused hypoxia in a compromised fetus - and which are quoted as an argument for epidurals - took laboring monkeys, pinched their toes, shined bright lights in their eyes, or jumped up and down in front of their cages (Simkin 1986). The monkeys did fine - until doctors hurt or frightened them.

Moreover, although epidurals relieve pain, one study found they did nothing to relieve stress. Wuitchik, Bakal, and Lipshitz (1990) asked laboring women what they were thinking at various points in labor and rated their reponses on a scale measuring coping versus distress. No differences were found between women who had epidurals and those who did not. The solution to undue stress in labor seems to be not an epidural, but supportive care and a relaxed, peaceful environment. As Simkin says, "Much of the stress of labor is preventable because many of the stressors . . . are imposed in the form of thoughtless routines, unfamiliar personnel, and technological interventions."

Meanwhile, one report on serious nonfatal epidural complications in 500,000 women yielded an incidence rate of life-threatening complications of roughly 1 in 14,000 cases and a serious complications rate overall of 1 in 5000 (Scott and Hibbard 1990, abstracted below). Another study reported a 1 in 3000 life-threatening complication rate (Crawford 1985, abstracted below). Women have died of epidural anesthesia but never of the pain of labor.
Drugs have been withdrawn from the market or forced into restricted use because of serious adverse reactions in the range of 1 in 1000 to 1 in 30,000 (Cohn 1989), yet epidurals are enthusiastically promoted to healthy women undergoing a normal process who are told the advantages are overwhelming and the risks are nil.
Epidurals are like any other obstetric intervention: they have their place, but they are a mixed blessing.
Notes: The British use extradural for epidural.

I have limited the abstracts to studies primarily of bupivacaine because that seems overwhelmingly to be the anesthetic of choice.

To show that adverse effects are not dose-dependent, I have listed concentrations after the citation.

Most articles refer to epidural analgesia, a softer word meaning "relief of pain." I use anesthesia, meaning "loss of sensation," because of its more serious connotation.

For a list of the generic and equivalent trade names of the medications used in epidurals, see Table 13.1.

SUMMARY OF SIGNIFICANT POINTS

Epidurals substantially increase the incidence of oxytocin augmentation, instrumental delivery (which increases the incidence of deep perineal tears), and bladder catheterization, although the effect seems to depend on obstetric management. (Abstracts 2-9, 11-15, 17, 23, 26-28, 32-34)

In primiparas, epidurals substantially increase the cesarean rate for dystocia. Here, too, the effect may depend on management. (Abstracts 2, 5-7, 10-15, 26, 33)

THE BABY WILL NOT ROTATE TO THE CORRECT POSITION FOR BIRTH!  Epidurals decrease the probability of an occiput posterior (OP) or occiput transverse (OT) baby's rotating. Oxytocin does not help. (Abstracts 2-3, 8-9, 13-14,28)

Having the epidural at 5 cm dilation or more greatly reduces excess incidence of OP and OT babies and cesarean for dystocia. (Abstracts 13-14)

Epidurals may not relieve any pain or may not relieve all pain. (Abstracts 14, 20, 27)

Innovations in procedure - lower dosages, continuous infusion, adding a narcotic - have not decreased epidural-related problems. (Abstracts 6-7, 10, 13-15, 19,27, 32-35, 42)

Delaying pushing until the head has descended to the perineum increases the chances of spontaneous birth.* Evidence is divided as to whether letting the epidural wear off increases spontaneous delivery. (Abstracts 3-5, 7)
*Two recent studies have claimed that delayed pushing did not increase the spontaneous birth rate, but in neither case was pushing truly delayed. The mean wait time was 52 minutes in one (Gleeson and Griffith 1991), and 72% began pushing less than one hour after full dilation in the other (Manyonda, Shaw, and Drife 1990).

Maternal complications of epidurals include (Abstract 20,1/3000 potentially life threatening; Abstract 22, 1/14,000 potentially life threatening; Abstract 36; 3-10/10,000 high spinal or intravascular):

Maternal hypotension (Abstract 1, 1.4-12%; Abstract 7, 10%; Abstract 15, 16%; Abstract 17, 32% in high-risk population; Abstract 27, 5%). This reduces uteroplacental blood supply and can cause fetal distress. High-risk babies are at particular risk because they lack reserves to cope. (Abstracts 1, 7, 15, 17-19,20, 32)

Convulsions (Abstract 22, 4/100,000). (Abstracts 19-20, 22, 42)

Respiratory paralysis (Abstract 22, 16/million). (Abstracts 19-20, 22)

Cardiac arrest (Abstract 22, 6/million). (Abstracts 1, 16, 19-20, 22, 36)

Allergic shock (Abstract 22, 2/million). (Abstracts 19, 22)

Maternal nerve injury through injury by the needle or catheter, poor positioning, forceps injury, infection, hematoma (bleeding at the site), or subarachnoid injection of chloroprocaine. The last three usually cause permanent damage (Abstract 21, 36.2/10,000 with epidurals versus 2.4/10,000 with no analgesia, all temporary; Abstract 22, 8/100,000, 4/million permanent; Abstract 40, 24% or more "nerve root irritation"). (Abstracts 1, 16, 18-22, 40-41)

Spinal headache, an incapacitating headache that can last days (Abstract 19, up to 50% with dural puncture; Abstract 22, 3/100,000; Abstract 24, 0.1% of all epidurals). (Abstracts 19, 22, 24)

Increased maternal core temperature, an additional stressor on both mother and fetus that may lead to a septic workup to rule out infection in the baby. (Abstracts 30-31)

Temporary urinary incontinence. (Abstract 22)

Long-term (weeks to years) backache (Abstract 24, 18.2% versus 10.2% nonepidural), headache (Abstract 24, 4.6% versus 2.9% nonepidural), migraines (Abstract 24, 1.9% versus 1.1% nonepidural), numbness or tingling. (Abstracts 20, 24)

Serious complications occur despite proper procedure and precautions. The epinephrine test dose can cause complications. (Abstracts 16, 18-20, 26, 36-42)

Epidural anesthetics "get" to the baby. (Abstracts 15-16, 19, 27-28)

Epidurals do not protect the fetus from fetal distress. In fact, they cause abnormal fetal heart rate (FHR), sometimes severe, which may occur in association with or independent of maternal blood pressure (Abstract 7, 11%; Abstract 15, 43% bupivacaine, 16% chloroprocaine, 10% lidocaine; Abstract 17, 9.7% associated with maternal hypotension in a high-risk population; Abstract 26, 11%; Abstract 34, 20%). (Abstracts 7, 12-15, 17, 19-20, 26-27, 32-34, 37, 42)

Epidurals may cause neonatal jaundice. (Abstracts 25, 28)

Epidurals may cause adverse neonatal physical and behavioral effects. (These are both direct effects and indirect effects from the increased rate of labor complications and interventions.) The importance of the behavioral effects is debated. (Abstracts 1,15, 28-29)

Epidural anesthesia may relieve hypertension, but hypertensive women are at particular risk of epidural-induced hypotension, which reduces placental blood supply. (Abstracts 17-18)
The 'Caine Family

Generic Name bupivacaine 2-chloroprocaine lidocaine mepivacaine

Trade Name Marcaine, Sensoricaine Nesacaine Xylocaine Carbocaine