PAIN RELIEF BY DRUGS

In this country, for every patient having natural childbirth, hypnosis, and psycho-prophylactic pain relief added together, there are at least one hundred receiving drugs to assuage or obliterate the pains of labor and delivery.

When the contractions of the uterus become frequent and moderately severe, in the primipara at approximately four centimeters’ or two fingers’ dilation, and in the multipara as soon as labor is well established, analgesic and amnesic drugs are usually administered.

It is important at this point to differentiate clearly between an analgesic, an amnesic, and an anesthetic. An analgesic simply diminishes the sense of pain; aspirin, for example, is a mild analgesic. An amnesic is a drug with the specific property of creating forgetfulness; it erases the memory of current events. The recipient has no knowledge of what occurs between the time he is given the injection and several hours later when its effect wears off. An anesthetic obilerates all sensation, either through the production of transitory unconsciousness (general anesthetic) or by temporarily interrupting the pathway by which sensory nerves communicate pain and other sensations to the brain (conduction anesthetic).

The History of Pain Relief in Obstetrics

When did medical science first concern itself with the sufferings of the parturient woman? From time immemorial it had always been considered woman’s sacred heritage to bring forth children ‘in sorrow.’ Had not God ordained it?

I have searched a dozen authoritative obstetrical texts of the sixteenth, seventeenth, eighteenth, and early nineteenth centuries, and there is not a single reference to the use of drugs for the relief of pain in travail, although many pain-relieving drugs were known and employed in general surgery and medicine. For a kinswoman who injured her back when six months pregnant, the greatest obstetrician of Renaissance France, Mauriceau, prescribed in 1668 ‘at two several times a small grain of Laudanum in the Yolk of an Egg, a little to ease her violent pains.’ However, his famous book contains not so much as an ‘I am sorry’ for the pains of labor. Some of these early authors devoted pages to the instruction of medical personnel in the proper conduct of tedious, painful births, but not a word was included about mitigating drugs.

Not only were labor pains unrelieved, but nothing was done to relieve the horror of obstetrical operations. Without an anesthetic or any other drug, Chamberlen, the inventor of the forceps, worked unsuccessfully for three hours to deliver a rachitic dwarf by means of his then secret instrument.

After giving up my vain search for early examples of the relief of pain in childbirth, 1 chanced upon an essay by Sir James Young Simpson of Edinburgh, the intrepid innovator who conducted the very first delivery under anesthesia.

Eighty-eight years before my search of early medical sources for a reference to pain relief in birth, his search had been equally fruitless.

Simpson administered the first obstetrical anesthetic during the delivery of a poor woman in the slums of Edinburgh. She was ‘etherized shortly after nine o’clock’ on January 19, 1847. Simpson immediately realized the full import of the occasion. By chance, on the same day he was apprised of his appointment as one of Victoria’s Scottish physicians. He considered this the lesser of the two events, for three days later, in reporting them to his brother, he wrote: ‘Flattery from the Queen is perhaps not common flattery, but I am far less interested in it than in having delivered a woman this week without any pain while inhaling sulphuric ether. I can think of naught else.’

Gauss of Freiburg, Germany, was the first to institute and advocate pain relief during labor. In 1907 he introduced a combination of morphine and scopolamine for this purpose. The former diminished pain; the latter dimmed memory. He called his technique Ddmmerschlaf, ‘twilight sleep’; while under its influence the patient remained in a kind of mid-state between consciousness and unconsciousness.

No phase of modern childbirth is more in flux than the conquest of its pain.

To understand the question, one must distinguish between the pain of labor preceding birth and the pain of actual birth itself. We shall term the one labor pain, the other birth pain.

At the Johns Hopkins Hospital, more than three decades ago, when I cut my eyeteeth in the art of midwifery, obstetrical pain relief was simple. Labor pain was treated either by what we called vocal anesthesia—pep talks along the well-grooved line, ‘It can’t hurt as much as you make out’—or by the injection of a small dose of heroin, an opium derivative. Just before the birth this was supplemented by nitrous oxide gas given intermittently with the last ten or twenty labor pains. (Nitrous oxide is familiar to most because of its use in tooth extractions.) For birth pain the patient was inexpertly anesthetized into unconsciousness by nitrous oxide, nitrous oxide and ether, or chloroform.

By now the whole field has become immeasurably improved and complicated.

Analgesics

Many drugs and combinations of drugs are available to the obstetrician for the relief of labor pains. They may be given by mouth, rectally, or by hypodermic injection directly in a vein or deep into a muscle. The intravenous avenue is most rapidly effective, as the drug is placed into the circulating blood and immediately affects the brain; when given by another route, it must first be absorbed into the circulation before it can act. Today the most popular drug is Demerol, given in combination with scopolamine. The latter, a member of the belladonna family, is the amnesic, the eraser of memory; the former deadens pain and creates an overpowering urge to sleep when given in sufficient quantity. Occasionally other analgesic drugs, such as Sparine or one of the barbiturates (Seconal) is added to the two standbys.

In successful cases, under the influence of the drug combination, the patient soon falls into a deep, quiet sleep between pains, but groans and moves about in a restless manner with each pain. The somnolent state continues into the second stage of labor and for several hours after delivery. When the patient wakes, the obstetrician is rewarded by hearing her ask, ‘Doctor, when am I going to have my baby?’ The quickest way I know to prove that the child is already born is to guide the patient’s hand to her own abdomen. Puzzled, she seeks for the familiar mountainous lump; when she finds it gone and replaced by a sunken valley the silliest, happiest grin steals across her face.

The relief of labor pain is tricky business. Each time a drug is given the doctor must ask himself three questions: ‘Is this drug, in the dose prescribed, safe for the mother? Is it likely to lengthen labor by diminishing the force of the contractions? And may it be injurious to the baby?’ Most drugs given the mother, no matter by what route of administration, rapidly gain access to her blood and forthwith pass through the placenta into the fetus’s blood. This is the case when analgesic drugs are used. As a group the analgesics are nervous depressants, depressing not only the sensation of pain but other nervous mechanisms, including respiration. The mother’s breathing center, located in the brain, is relatively resistant to their depressing effects, but not so the respiratory center of the newborn, which is highly susceptible to such inhibitory influences. For this reason particularly, and to a lesser extent for the safety of the mother and the possible slowing effect on labor, the obstetrician must be chary of the amount of pain-relieving drugs be prescribes during labor. All too often he must turn a reluctant deaf ear to the laboring woman’s importunate pleadings for more and yet more drugs. Her goal is total eradication of pain; his goal is maximum relief within the bounds of safety for mother and child. Not only drug dosage but the timing of administration requires care. If given too early, before labor is well established, drugs may halt or lengthen the process. I am always puzzled by the woman who says, ‘My doctor knocked me out with the very first pain, and I didn’t feel a thing.’ She either forgets because of the amnesic beneficence of scopolamine or dramatically distorts the truth.

Anesthetics

Obstetrical anesthesia, rendering a patient completely insensible to pain during actual delivery, has come of age. Until the last few years it had been the stepchild of the science of anesthesiology. In contrast to the attitude toward anesthesia in general surgery, it was felt that literally anybody could put a woman to sleep to have a baby. When deliveries were conducted at home, it was common practice to convert the husband or some other relative into a temporary anesthetist. And in hospitals novice anesthetists, senior medical students, or inexperienced interns were frequently used for delivery anesthesia. As a matter of fact obstetrical anesthesia is difficult anesthesia—first, because you have the interests of two patients, mother and baby, to consider, and these interests are sometimes antithetic. In the second place, the obstetrical patient is often poorly prepared for her anesthesia. The surgical patient is admitted to the hospital for rest and preoperative starvation at least eighteen hours prior to a scheduled operation. On the other hand, the woman in labor may enter the hospital just after a hectic day of domesticity, climaxed by a big, indigestible dinner. The importance and difficulties of obstetrical anesthesia are constantly gaining recognition, so that more and more births are being attended by two medical experts, the obstetrician and the anesthesiologist.

Several anesthetics are available to eliminate birth pain. They can be divided into two main categories, general and conduction—the latter also termed local or regional. A general anesthetic affects the whole body, creating anesthesia by temporary but complete unconsciousness. A conduction anesthetic functions differently. It simply interrupts the pathway from a specific area where the pain stimulus is received to the brain cells where it is appreciated as pain. An electric light offers a homely analogy. The stimulus is the wall switch, the conduction pathway the wires in the wall, and the brain which converts the stimulus the electric bulb on the ceiling. If the conducting wires are cut, the bulb will not light, no matter how many times you flip the switch.

General anesthetics until relatively recently were almost wholly inhalation anesthetics, gases inhaled into the lungs and absorbed immediately into the bloodstream. Since the blood bathes the whole body, the anesthetic gases soon reach the brain, and when sufficient concentration is attained in the brain, unconsciousness results. Another method is to bypass lung absorption by injecting the anesthetic agent, a water solution of a chemical powder, directly into the bloodstream. The general anesthetics, no matter whether inhalation (nitrous oxide, ether, cyclopropane, ethylene, etc.) or intravenous (sodium pentothal, evipal, etc.), soon pass across the placenta into the baby’s circulation and may narcotize it (make it sleepy). When general anesthetics are superimposed on heavy doses of analgesics, a fair proportion of sleepy, sometimes very sleepy, babies results. They do not announce their entrance into the world with loud trumpeting, but they come around quickly with conservative, careful handling and soon are indistinguishable from the babies of mothers who did not receive general anesthesia.

Conduction anesthesia acts locally, does not enter the mother’s bloodstream, and therefore cannot find its way across the placenta to the baby’s circulation. Therefore babies born to mothers given conduction anesthetics are likely to howl lustily the minute they are born.

There are three ways in which conduction, or regional, anesthesia may be used in obstetrics. One is by local infiltration. When the baby is ready to be delivered, the doctor eliminates birth pain by injections of one of the cocaine drugs into the lower birth passage, thus numbing the perineum, the area between the rectum and the vagina, as well as the lower vagina itself. The obstetrician may accomplish this by widely injecting the whole area with the drug, or by injecting a single spot on either side, blocking the nerve fibers as they fan out from the main nerve trunk. The second method is injection of the conduction anesthetic into the spinal fluid surrounding the lower spinal cord. The needle is introduced into the spinal canal by inserting it in the midline of the lower back between two vertebrae, and a single dose of drug administered. The needle is then withdrawn. One may use either an ordinary water solution of the drug or a dextrose or sugar solution. The former diffuses rapidly, bathing the lower portion of the spinal cord, and produces complete anesthesia to the navel or above. The latter mixture is hyperbaric—that is, heavier than the spinal fluid—and if the patient is kept sitting upright for thirty seconds after the injection and then lies down immediately, the dextrose anes- thetic solution sinks to the bottom of the spinal canal, numbing only the lowermost nerve trunks. This produces anesthesia in a restricted area, an area which ordinarily contacts a saddle when one is riding horseback; therefore it is termed saddle-block anesthesia. Since both stop labor, neither spinal nor saddle-block can be given for labor pain but only for birth pain, and they are ideal for delivery except for two drawbacks. First, about 6 per cent of these anesthetics are followed by severe and sometimes protracted headaches which eventually disappear without any aftermath. The second drawback is that they not infrequently induce a temporary drop in blood pressure; therefore, the patient must be carefully observed, with blood pressure readings every five or ten minutes during the first hour after injection.

The third type of conduction anesthesia is caudal (Latin: cauda—’tail’), so named because if human beings had tails the point of injection would be just at the base of the tail, into the so-called caudal space. This space is below the spinal canal; the drug simply bathes the nerve trunks as they make their exit. The caudal anesthetic is given continuously—that is, additional amounts are injected into the caudal space as soon as it is evident that the numbing effect is beginning to wear off. This requires that a needle be left in place. An interesting modification is the substitution of a plastic catheter (tube) for the needle. The tiny catheter is threaded into place through the large needle, the needle withdrawn, and the protruding end of the catheter fixed securely in position by adhesive tape.

The caudal method is unique since it is used in the same patient as a combined analgesic and anesthetic to eliminate labor pain as well as birth pain. Injections are begun when labor is well established and the cervix has become partially dilated, and are continued until after delivery. Caudal anesthesia sounds like the answer to a maiden’s prayer, and when it works well it truly is. It does not have the unpleasant headache aftermath which occasionally curses spinal and saddle-block anesthesia.

Why isn’t caudal anesthesia the perfect obstetrical pain-relief method that modern obstetrics has sought so earnestly? First, it is technically difficult; great skill and experience are required to lodge the needle in the caudal space. Second, the patient must have a vigilant nurse or physician constantly at her bedside to check when more drug is needed and observe for fluctuations in blood pressure. In many hospitals such available technical personnel is an unobtainable luxury. Third, some women are constructed with so small a caudal canal that even a master technician cannot enter the space. Fourth, if given too early, or if the labor is not of the rapidly progressive type, it may prolong labor.

In summary, then, modern obstetrics has made tremendous progress in the relief and even elimination of the pain of childbirth. Today no woman need suffer as her mother did. The obstetrician has a bag full of techniques, from natural childbirth to caudal anesthesia. He will choose the technique with which he is experienced, one he considers eminently safe for the mother and baby, and one that is best suited to the particular patient. A recent book by two authorities in this field, Drs. Robert Hingson and Louis Hellman, summarizing a study of over 10,000 deliveries by various anesthetic techniques, shows quite clearly that as far as the baby is concerned any type of birth anesthetic given the mother is equally safe. The only important variable as far as fetal results are concerned is the competence of the anesthetist.

Which for Me, ‘Natural’ or ‘Medicated’ Childbirth?

I am sure that many readers are asking themselves the above question. I am equally certain that I cannot answer it for them. Nevertheless, through extensive experience, I can make some observations which may prove helpful.

Do not make the decision on the basis as to which is safe for you and your baby. Both are safe.

Do not make the choice because some relative, and this includes your husband, prefers one or the other method for you. In this, you have no one to please except yourself. ‘Natural’ childbirth is well suited to the intelligent, widely read patient who feels that having a baby is the greatest of life’s many experiences and does not want to miss a minute of it. She wants to be wide awake when contractions become strong to sample what they are like. She wants to feel the pressure of the baby on her pelvic muscles and wants the thrill of helping push the baby out. She wants to know when she is taken to the delivery room and, above all, to hear her baby’s first cry; while still on the delivery table, perhaps before the cord is cut, she wants to cradle the baby in her arms.

In contrast is the woman who has a low threshold for pain, who hates to be hurt. She looks forward to several children and fears that if labor and birth are too uncomfortable she will lack the spunk to stage a repeat performance. She is very likely to spend a half century with her child, and missing the first few hours of their association is a very brief fragment of the whole. To her, temporary separation from reality at such a time, through the boon of safe analgesia and anesthesia, is a welcome goal.

Then there is the woman who falls in neither group. She is uncertain. In this case, I advise giving ‘natural childbirth’ a trial. Read the books, take the classes, if they are available in your community. Be prepared! Fortunately, a decision in favor of unmedicated childbirth is not irrevocable. Try labor without drugs. It may be much easier than you anticipated. If the going gets rough, ask for a little medication, perhaps half of the standard dose. Then, if you still find it too rugged, ask for full drug relief and retreat into the bliss of temporary severance from reality.

Above all, do not feel defeated if you find you want full medication. No one else than you’ is really concerned; therefore have the type of labor which best suits your needs. Certainly if you tell your teen-age daughter fifteen years hence that you had her with medicated or non-medicated childbirth, she could not care less.