Anesthesia and analgesia in obstetrics

Abstract

Anesthesia in obstetrics includes the medical attendance of women in the delivery room as well as giving anesthesia for cesarean sections in the operating room. Over the last years the treatment of labor pain with epidural anesthesia has been modified. Whereas a couple of years ago local anesthetics were used almost exclusively, the recent trend goes toward a combination of local anesthetics with opioids. Using this combination the total amount of local anesthetic can be greatly reduced, whilst maintaining most of the motor function during labor. There is evidence the combination of local anesthetics with opioids can reduce the number of operative vaginal deliveries such as vacuum extraction or forceps. The systemic application of opioids remains unaffected by the local application and its significance is unaltered, even though the effectiveness compared to epidural application in managing labor pain is far inferior. Opioids applied systemically often have an unwanted sedative effect in the mother and have the potential for respiratory depression in the newborn. The question, whether epidural anesthesia increases the frequency of cesarean sections remains to be answered. Studies so far present discrepant results and do not show a causal relationship between the use of epidural anesthesia and increase in cesarean section rate. Regarding cesarean sections, there has been a trend in the operative field over the last years towards the use of regional anesthesia. This is the consequence of the fact that anesthesia related mortality during cesarean sections is still mainly due to hypoxia and aspiration during induction of anesthesia. The advantage of spinal anesthesia over epidural anesthesia is faster onset, more reliable sensitive block and a lower failure rate. Downside of the use of spinal anesthesia is a higher incidence of hypotension in the mother, which, however, is not a serious complication if treated adequately. Regarding the continuous application of local anesthetics via a spinal catheter, no definite statements towards benefits compared to other regional techniques can be made due to the lack of adequate amount of patient studies. Theoretically this method seems advantageous as it allows to adjust the administration of local anesthetics and opioids to the individual needs in a very refined way. Emergency situations, such as emergency cesarean sections, life threatening hemorrhage, eclampsia, and HELLP syndrome, are the main risks of the anesthetic practice in obstetrics. Their beneficial outcome is highly dependent on the coordination of logistic problems, good communication and coordination within an interdisciplinary team of obstetricians and anesthesiologists.