Some anesthesiologists perceive obstetric anesthesiology as a “backwater” of anesthesia care. It is simple: place a needle in a laboring woman’s back and inject local anesthetic/opioid solution for labor analgesia OR place a needle in a woman’s back for cesarean delivery to provide surgical anesthesia OR very occasionally administer general anesthesia in an emergency. But like other subspecialties of anesthesiology, and just as important to nuanced and safe care, new research in the past decade has contributed to improved obstetric anesthesia care. Given that around the world, cesarean delivery is the most commonly performed major operation, and 4.3 children are born every second, ^a

a http://www.indexmundi.com/world/birth_rate.html .

In this issue of the Journal, experts from around the world have summarized recent advances in obstetric anesthesiology. We have chosen a broad variety of topics that include updates in labor analgesia, cesarean delivery anesthesia and general obstetric knowledge important for the anesthesiologist caring for the obstetric patient.

Although the rate of cesarean delivery is increasing worldwide, most women still deliver vaginally; thus, safe and effective labor analgesia is a critical aspect of obstetric anesthesia care. In high-resource countries, neuraxial labor analgesia is considered by many to be the gold standard against which all other forms of analgesia are measured. However, for multiple reasons, systemic opioid analgesia is still an important mainstay of labor analgesia. An overview of parenteral opioid labor analgesia discusses its current role, including the role of remifentanil. Several decades ago, maintenance of epidural labor analgesia was simple: inject local anesthetic through an epidural catheter, and when its effect waned, inject more, and when the effect of the first top-up waned, inject another top-up, and when the effect of the next top-up waned, inject another one…. Fortunately, we have come a long way from this crude method! New methods to effectively maintain labor analgesia for the duration of labor using modern infusion pump technology are reviewed. Precision individualized medicine is the new buzzword, and its role in obstetric anesthesia is being investigated. Although in its infancy, we have no doubt that pharmacogenetics will play a role in optimal obstetric anesthesia care in the future. Some old problems remain: unintentional dural puncture with a large-bore epidural needle, followed by postdural puncture headache (PDPH) is still distressing to the new mother and her anesthesiologist. Although an active area of investigation, seeking methods to avoid and treat PDPH, epidural blood patch remains the gold standard treatment.

Providing timely and safe anesthesia for intrapartum cesarean delivery is an important contributor to optimal maternal and neonatal outcomes. But how is “timely” defined? Is 30-min still the magic decision-to-delivery interval? New data suggest that, while striving for a short decision-to-delivery interval may serve as a useful quality tool, the system components necessary to routinely achieve a short interval should be the real targets (i.e., multidisciplinary team care, effective team communication). Many experts agree that neuraxial (primarily spinal) anesthesia for cesarean delivery is the best for the mother and baby in most circumstances. However, most women become hypotensive after the initiation of spinal anesthesia, and maternal uteroplacental perfusion will decrease. Left untreated, this leads to a miserable mother (nausea and vomiting) and neonatal acidemia. A large body of research in the past two decades has improved our knowledge of the mechanisms, prevention and treatment of spinal anesthesia-induced hypotension. Providing obstetric care does not stop at delivery. Safe and effective postpartum analgesia is important for the wellbeing of the new mother and her child. Recent studies have linked acute postpartum pain to depression and chronic pain. Anesthesiologists play an important role in the treatment of acute postpartum pain, and research continues to address this important topic.

The use of bedside ultrasonography is becoming routine for many aspects of anesthesia care, including assessing cardiovascular status, attaining peripheral and central vascular access, and assessing anatomy before and during initiation of nerve blocks. Like other areas of anesthesia, its use in obstetric anesthesia care has contributed to improved patient care and outcomes. Although childbirth has become markedly safer in the past century, maternal death is still a reality. Anesthesiologists are the critical care physicians of the obstetric unit; they can play a vital role in the development of safe obstetric healthcare systems (e.g., development of protocols and safety bundles, participation in multidisciplinary teams) and for individual patients, patient rescue. One critical role is resuscitation in the setting of postpartum hemorrhage, a major contributor to maternal morbidity and mortality around the world. A second major cause of maternal morbidity and mortality is preeclampsia/eclampsia. Again, anesthesiologists, as critical care physicians, are ideally suited to assist our obstetric colleagues in the management of these unstable patients.

In summary, anesthesiologists play an important role in the modern obstetric unit. The provision of safe labor analgesia and cesarean delivery anesthesia is one important role. Another is an understanding of maternal comorbidities and the co-management of these morbidities with our obstetric colleagues. We hope these review articles will serve to update readers on new knowledge in this important field.