Where did this safe and powerful injection come from, and how can we utilize it more widely? First, a local anesthetic is used to ensure minimal discomfort. Usually, the drug is injected via a catheter, and causes an instant loss of sensation in the spinal cord.
The nerve fibers are temporarily unable to send any signals, including pain signals, anywhere near the spinal cord. Abstract In , the first Epidural anesthesia via a caudal approach was independently described by two FrenchmanJean-Anthanase Sicard and Fernand Cathelin.. Publication types English Abstract Historical Article.
The dose of local anesthetic necessary to achieve effective labor analgesia will depend on the intensity and location of the patient's pain. These in turn depend on the variables discussed earlier, including the amount and rate of cervical dilation; the strength, frequency and duration of uterine contractions; and the position of the fetal head at the time epidural analgesia is requested.
Approximately 10 mL of 0. Thereafter, maintenance of epidural analgesia may be achieved with either intermittent bolus injections, continuous epidural infusion or patient-controlled epidural analgesia. In most cases, analgesia may be maintained with a solution of local anesthetic more dilute than that used for induction.
The rightsholder did not grant rights to reproduce this item in electronic media. For the missing item, see the original print version of this publication. The supine position is contraindicated in women receiving epidural analgesia during labor.
Compression of the abdominal aorta and the inferior vena cava aortocaval compression by the term gravid uterus may concurrently decrease uterine arterial pressure and increase uterine venous pressure.
Consequently, uterine perfusion pressure uterine arterial pressure minus uterine venous pressure may be substantially reduced even in the presence of normal brachial arterial blood pressure measurements concealed aortocaval compression.
When maternal hypotension occurs during epidural analgesia, it is essential to verify that the patient is not supine. The onset of fetal descent causes substantial distention of the vagina and perineum, typically resulting in severe pain. It is important to ensure that the segmental extent of epidural analgesia has spread to include the S nerve roots to maintain analgesia during this stage of labor. Achieving adequate perineal analgesia is especially important in women in whom episiotomy or the application of forceps is probable.
Complaints of rectal pressure with progressive descent of the fetal head should alert the anesthesiologist that sacral analgesia may be inadequate for delivery.
Women who progress into the second stage of labor soon after induction of epidural analgesia seldom have adequate sacral blockade and often require additional epidural boluses of local anesthetic before delivery.
On the other hand, women who have been receiving continuous epidural analgesia for many hours often have excellent perineal analgesia at delivery. In spite of the widespread acceptance that epidural analgesia has achieved among many physicians and patients, disagreement remains regarding the effect of intrapartum epidural analgesia on the subsequent progress of labor and the mode of delivery.
Several retrospective studies consistently demonstrated an association between epidural analgesia and increased durations of both the first and second stages of labor, oxytocin augmentation, instrumental vaginal delivery and cesarean section for dystocia. In these studies, the probability of cesarean section for dystocia was reported to be increased three- to six-fold by the intrapartum administration of epidural analgesia. Such studies are biased by the fact that women who progress rapidly through labor often have less pain and are less likely to request and receive regional analgesia.
Randomized, prospective studies have produced contrasting findings regarding the effects of epidural analgesia on labor and mode of delivery. It is unclear whether or not epidural block prolongs the first stage of labor. Controversy remains as to whether epidural analgesia predisposes parturients to a greater risk of cesarean delivery for dystocia. In the first of these studies, Ramin and colleagues 22 reported that the risk of operative delivery for dystocia was increased nearly two-fold among women of mixed parity who were given epidural analgesia rather than intravenous meperidine Demerol analgesia.
Two years later, Sharma and associates 23 observed identical cesarean section rates among women randomized to receive either epidural analgesia or patient-controlled intravenous meperidine analgesia. One important methodologic difference between these two investigations was that parturients in the latter study were analyzed on an intent-to-treat basis, regardless of the type of pain relief ultimately administered.
Perhaps most illuminating are data from institutions where the use of epidural analgesia has increased abruptly over a short period of time.
Air Force hospital. In the month period preceding enforcement of the new policy, 13 percent of parturients received epidural analgesia; the incidence of cesarean delivery for dystocia was 8 percent. During the first year that epidural block became widely available, 59 percent of parturients were given epidural analgesia during labor.
The incidence of cesarean section delivery for dystocia decreased although the decrease was not statistically significant to 5 percent—despite a percent increase in the use of intrapartum epidural analgesia. Discovery of opioid-mediated spinal analgesia led to speculation that spinal morphine administration would result in acceptable labor analgesia without local anesthetic-induced sympathetic and motor block.
Unfortunately, pain relief following subarachnoid administration of morphine is often slow in onset, inconsistent in quality especially during the second stage and accompanied by a high incidence of pruritus, nausea, urinary retention and sedation.
On the other hand, intrathecal administration of short-acting lipid-soluble opioids e. Specifically, subarachnoid sufentanil or fentanyl each produce excellent first-stage analgesia within five minutes that lasts about 90 minutes.
Limitations to the intrathecal administration of a lipid-soluble opioid for labor analgesia include a propensity for intense although brief pruritus, a relatively short duration of action and an inability to produce adequate pain relief during the second stage of labor. Some physicians have administered a lipid-soluble opioid with a very small dose of morphine 0. The unique ability of intrathecal lipid-soluble opioids to produce rapid onset of pain relief during the first stage of labor clearly cannot be equaled using epidural techniques.
Thus, some anesthesiologists facilitate the onset of labor analgesia by injecting a single dose of fentanyl or sufentanil with or without a local anesthetic intrathecally before placing the epidural catheter combined spinal-epidural analgesia.
This technique allows prompt onset of pain relief through spinal anesthesia without sacrificing the flexibility of continuous epidural analgesia. The increased availability and effectiveness of epidural analgesia have altered the expectations of many women regarding intrapartum pain control. A significant number of parturients are requesting this form of analgesia for relief of labor pain.
Family physicians who perform obstetrics should discuss this method of pain control with their prenatal patients. The risks and benefits of epidural analgesia, as well as other options for pain control, should be objectively presented to each woman well before the onset of labor.
In addition, women can be encouraged to attend childbirth classes to help them prepare for stresses that may arise during labor and delivery. Careful patient evaluation, meticulous technique during epidural catheter placement and appropriate dosing of medication minimize the risk of serious complications from epidural analgesia.
He advocated the use of epidural anesthesia for a wide variety of procedures. Notable exceptions included radical mastectomy brachial plexus block was also required and upper extremity surgery better done with brachial plexus anesthesia.
Dogliotti first described the modern loss of resistance technique and classic grip of needle and syringe. Although a surgeon by training, he took a profound interest in anesthesia.
They published in the United States in By , Guiterrez and Ruiz learned from the work of both Pages and Dogliotti and were very agressive in their use of the technique. References: 1 Pages F: Anestesia metamerica.
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