Postcesarean Analgesia With Epidural Morphine After Epidural 2-Chloroprocaine: A Randomized Noninferiority Trial.

BACKGROUND: Previous studies have suggested that administration of epidural 3% 2-chloroprocaine (CP) before epidural morphine results in decreased analgesic efficacy of epidural morphine. We sought to determine whether these observations were a result of antagonism or a window period between the conclusion of surgical anesthesia for cesarean delivery and the peak onset time of epidural morphine, and whether a method to preserve the analgesic efficacy of epidural morphine exists. METHODS: Term parturients scheduled for nonemergent, unscheduled cesarean delivery with preexisting labor epidural catheters were recruited for this exploratory, randomized, single-blinded, noninferiority trial. Subjects were randomized to initial dosing to a T4 dermatome surgical anesthetic level with either 3% CP or 2% lidocaine with 1:200,000 epinephrine and sodium bicarbonate (LEB). Subsequent redosing for both groups was performed with LEB at regular intervals. Epidural morphine 3 mg was administered to both groups after delivery. Assessing the difference between the 2 groups in total opioid use for the first 24 hours after epidural morphine administration was the primary objective. The noninferiority margin of 10 oral milligram morphine equivalents was prespecified based on previous noninferiority studies. Secondary end points included time from epidural morphine administration to first rescue opioid request, numerical pain scores, nausea/vomiting, and pruritus. RESULTS: Data were analyzed for 40 parturients, 20 in each group. The median 24-hour opioid consumption for the CP group was 0 (Q1 = 0 and Q3 = 15.6) oral milligram morphine equivalents compared to 15 (6.3-22.5) for the LEB group. The median difference was -7.5, with a 95% confidence interval -15 to 0. Noninferiority was concluded, as the confidence interval was less than the predetermined noninferiority margin of 10 oral milligram morphine equivalents. There was no treatment effect on time to first opioid request and no statistically significant differences in pain scores or nausea, vomiting, or pruritus at all time points (4, 8, 12, and 24 hours after epidural morphine administration). CONCLUSION: While designed as an exploratory study, initial epidural dosing with 3% CP and beginning subsequent redosing with LEB within 30 minutes of the initial CP bolus provided noninferior postcesarean analgesia with epidural morphine compared to initial epidural dosing and redosing with LEB. Previous observations of decreased analgesic efficacy of epidural morphine after epidural CP were likely due to a window period that may be mitigated by redosing with lidocaine; however, larger studies are necessary to confirm these findings.

Neuropathophysiology of preeclampsia and eclampsia: A review of cerebral hemodynamic principles in hypertensive disorders of pregnancy.

Preeclampsia and eclampsia are hypertensive disorders of pregnancy associated with abnormal placental vascular development. The systemic angiogenic imbalance, endothelial dysfunction and proinflammatory state caused by abnormal placental development results in abnormalities in renal, hepatic, pulmonary and neurologic function. Neurosensory symptoms related to pregnancy induced hypertension (PIH), the most devastating of which are intracranial hemorrhage and seizure, are among the leading causes of maternal and perinatal morbidity and mortality globally, yet risk stratification strategies and targeted therapies remain elusive. Current treatment for preeclampsia with severe features is limited to delivery, antihypertensive therapy, and magnesium sulfate seizure prophylaxis. Magnesium sulfate reduces seizure rates among severe preeclamptics, but predisposes patients to weakness, uterine atony, pulmonary edema and respiratory depression. Therefore, this drug should ideally be administered only to the subset of preeclamptics who are at increased risk for neurologic complications. While there are no objective methods validated to predict eclampsia, we hypothesize that measurement of optic nerve sheath diameters, optic disc height and middle cerebral artery transcranial doppler resistance indices may be useful in identifying subclinical cerebral edema, potentially allowing us to recognize those patients at highest risk for seizures. This summary of the current literature provides an initial framework for developing more sophisticated and noninvasive methods for identifying, monitoring and treating parturients who are at highest risk for neurologic complications from preeclampsia.

The effectiveness of a multidisciplinary, team-based approach to cesarean hysterectomy in modern obstetric practice.

OBJECTIVE: To examine the effectiveness of a multidisciplinary, team-based approach to management of cesarean hysterectomy. METHODS: In a retrospective chart review, data were analyzed from a quality assurance database of hysterectomies performed after cesarean delivery at one institution in the USA. Patients were identified through billing codes for cesarean delivery, cross-referenced to codes for hysterectomy. Demographic, reproductive, and outcome data were compared before (2000-2005) and after (2011-2013) implementation of a multidisciplinary team-based protocol. RESULTS: Across the two study periods, 107 cesarean hysterectomies were identified (69 pre-implementation, 38 post-implementation). In univariate analysis, the post-implementation group had fewer days in surgical intensive care than did the pre-implementation group (0.21 ± 0.41 vs 1.04 ± 2.44 days; P=0.011), and a lower frequency of febrile morbidity (4 [11%] vs 22 [32%]; P=0.033]. In multivariate analysis with adjustment for potential confounders, the likelihood of postoperative febrile morbidity was higher during the pre-implementation than the post-implementation period (adjusted odds ratio 3.5, 95% confidence interval 1.09-13.65; P=0.048). CONCLUSION: Outcomes were improved after the multidisciplinary team-based approach to cesarean hysterectomy was implemented. Team-based approaches to care of women undergoing cesarean hysterectomy are important to improve outcomes.

The Society for Obstetric Anesthesia and Perinatology consensus statement on the management of cardiac arrest in pregnancy.

This consensus statement was commissioned in 2012 by the Board of Directors of the Society for Obstetric Anesthesia and Perinatology to improve maternal resuscitation by providing health care providers critical information (including point-of-care checklists) and operational strategies relevant to maternal cardiac arrest. The recommendations in this statement were designed to address the challenges of an actual event by emphasizing health care provider education, behavioral/communication strategies, latent systems errors, and periodic testing of performance. This statement also expands on, interprets, and discusses controversial aspects of material covered in the American Heart Association 2010 guidelines.

Cardiopulmonary resuscitation and the parturient.

Cardiopulmonary arrest occurs in 1: 30 000 pregnancies. Although rare, optimal outcomes are dependent on the cause of the arrest, the rapid response team's understanding of the physiological effects of pregnancy on the resuscitative efforts and application of the latest principles of advanced cardiac life support (ACLS). Anaesthesia-related complications, secondary to difficult or failed intubation, and inability to oxygenate and ventilate can result in adverse outcomes for mother and baby. Experience in advanced airway management has been shown to decrease the incidence of brain death and maternal mortality. Awareness of lipid resuscitation of local anaesthetic toxicity is important. The effects of lipid resuscitation and its interference with ACLS medications are also important. Peri-mortem caesarean delivery of the foetus greater than 24 weeks' gestational age must be considered. Caesarean delivery should be performed no later than 4min after initial maternal cardiac arrest. A foetus delivered within 5min has the best chance of survival. Delivery of the baby helps in the maternal resuscitation efforts and recovery of circulation. Finally, the 2003 International Liaison Committee on Resuscitation (ILCOR) and the 2005 American Heart Association (AHA) advocate the provision of mild therapeutic hypothermia to the survivors of cardiac arrest. This will improve the neurological outcomes by decreasing cerebral oxygen consumption, suppression of the radical reactions and reduction of intracellular acidosis and inhibition of excitatory neurotransmitters.

Maternal morbidity, mortality, and risk assessment.

Maternal deaths in developed countries continue to decline and are rare. Maternal mortality statistics are essentially similar in the United States and United Kingdom. However, the situation is completely different in developing countries, where maternal mortality exceeds 0.5 million every year. This article not only assesses morbidity risks in some of the leading causes of maternal death but also highlights strategies to minimize the risks and to prevent maternal morbidity and mortality.

Intrapartum epidural analgesia and maternal temperature regulation.

OBJECTIVE: To examine maternal temperature changes after epidural analgesia. METHODS: A prospective cohort of nulliparas at term was monitored with hourly maternal tympanic temperatures after epidural analgesia (n=99). Temperature response after epidural analgesia was examined in the group as a whole. Subsequently, mean maternal temperature curves were compared between women who remained afebrile throughout labor (n=77) and women who developed intrapartum fever with body temperature greater than 100.4 degrees F (n=22). Baseline maternal characteristics were assessed. RESULTS: Women who later developed intrapartum fever had a higher mean temperature within 1 hour after epidural analgesia. In contrast, women who remained afebrile had no increase in core temperature. During the first 4 hours after epidural analgesia initiation, women who later develop intrapartum fever have an increase in mean tympanic temperature of 0.33 degrees F per hour. CONCLUSION: Epidural analgesia is not associated with increased temperature in the majority of women. Hyperthermia is an abnormal response confined to a minority subset, which occurs immediately after exposure. Our findings do not support a universal perturbation of maternal thermoregulation after epidural analgesia. LEVEL OF EVIDENCE: II.

Maternal corticosteroids to prevent intrauterine exposure to hyperthermia and inflammation: a randomized, double-blind, placebo-controlled trial.

OBJECTIVE: Intrauterine exposure to hyperthermia at term is associated with adverse neonatal neurologic outcomes. The objective of this study was to determine whether prophylactic maternal corticosteroid treatment prevents fetal exposure to hyperthermia and inflammatory cytokines after epidural analgesia. STUDY DESIGN: A 2-phase, randomized, institutional review board-approved, double-blind, placebo-controlled trial was performed. Term nulliparous women were enrolled at epidural placement. Patients with a temperature of >99.4 degrees F or with diabetes mellitus were excluded. In phase 1, 25 mg methylprednisolone (low dose) or placebo was administered every 8 hours. In phase 2, the treatment dose was increased to 100 mg every 4 hours (high dose). Our primary outcome was a rate of intrapartum fever of >100.4 degrees F. Secondary outcomes were fetal interleukin-6 levels and the rate of neonatal bacteremia. RESULTS: One hundred one patients were assigned randomly to placebo; 50 patients were assigned to the low-dose group, and 49 patients were assigned to the high-dose group. Treatment with the high dose resulted in a 90% reduction in maternal fever, compared with placebo and low dose therapy (2.0% vs 21.8% vs. 34.0%, respectively; P < .001). Neonatal sepsis evaluations were reduced significantly in the high-dose group (4.1% vs 17.8% vs 24%, respectively; P = .01), but the rates of asymptomatic bacteremia were increased (9.3% vs 0% vs 2.1%, respectively; P = .005). Median cord blood interleukin-6 levels were reduced with the high-dose steroid treatment, but this result was statistically significant only between the high-dose and placebo groups (24.0 +/- 38.5 vs 32.0 +/- 95.0 pg/mL, respectively; P = .02). CONCLUSION: Prophylaxis with high-dose corticosteroids significantly reduces fetal exposure to hyperthermia and inflammation. However, maternal high-dose corticosteroids increase the rate of neonatal asymptomatic bacteremia. Stress-dose corticosteroid use in labor should trigger consideration of a screening neonatal blood culture.

Airway problems in pregnancy.

OBJECTIVES: To provide a current review of the literature regarding airway problems in pregnancy and management. BACKGROUND: Obstetrical anesthesia is considered to be a high-risk practice that exposes the anesthesiologist to increased medicolegal liability. Anesthetic management of a parturient is a challenge because it involves simultaneous care of both mother and baby. Failure to appropriately manage a difficult or failed intubation increases the risk of hypoxemic cardiopulmonary arrest and/or pulmonary aspiration, resulting in a high probability of maternal morbidity and mortality. DATA: Anesthesia is the seventh leading cause of maternal mortality in the United States. Anatomic and physiologic changes during pregnancy place the parturient at increased risk for airway management problems. It is essential to perform a thorough preanesthetic evaluation and identify the factors predictive of difficult intubation. Airway devices such as the laryngeal mask airway, ProSeal, intubating laryngeal mask airway, Combitube, and laryngeal tube are described and have been used during failed intubation in pregnant patients. CONCLUSION: Teamwork between an anesthesiologist and an obstetrician is absolutely essential for the safety of both the mother and baby. Most of us tend to agree that airway emergencies have a way of occurring at the worst possible times. It is essential that all anesthesia care practitioners must have a preconceived and well thought-out algorithm and emergency airway equipment to deal with airway emergencies during difficult or failed intubation of a parturient.

Critically ill obstetric patients in an American and an Indian public hospital: comparison of case-mix, organ dysfunction, intensive care requirements, and outcomes.

OBJECTIVE: To compare case-mix, health care practices, and outcome in obstetric ICU admissions in inner-city teaching hospitals in economically developed and developing countries. DESIGN: Retrospective study. SETTING: Ben Taub General Hospital (BTGH), Houston, Texas, and King Edward Memorial Hospital (KEMH), Mumbai, India. PATIENTS: Women admitted during pregnancy or 6 weeks postpartum between 1992 and 2001. MEASUREMENTS AND RESULTS: Patients from BTGH (n=174) and KEMH (n=754) had comparable age, number of organs affected, incidence of medical disorders (30%), liver dysfunction, and thrombocytopenia. Fewer KEMH patients received prenatal care (27 vs 86%) and came to hospital within 24 h of onset of symptoms (60 vs 90%). They had higher APACHE II scores (median 16 vs 10), greater incidence of neurological (63 vs 36%), renal (50 vs 37%), and cardiovascular dysfunction (39 vs 29%). Severe malaria, viral hepatitis, cerebral venous thrombosis, and poisoning were common medical disorders. The BTGH group had higher incidence of respiratory dysfunction (59 vs 46%) and disseminated intravascular coagulation (40 vs 23%), placental anomalies, HELLP syndrome, chorioamnionitis, peripartum cardiomyopathy, puerperal sepsis, urinary infection, bacteremia, substance abuse, and asthma. More BTGH patients required mechanical ventilation and blood component therapy, whereas more KEMH patients needed dialysis. Of BTGH patients, 78.2% were delivered by cesarean section (vs 15.4%). Maternal (2.3 vs 25%) and fetal (13 vs 51%) mortality were lower in BTGH patients. CONCLUSIONS: There were marked differences in medical diseases, organ failure, and intensive care needs. Higher mortality in the Indian ICU may be due to difference in case mix, inadequate prenatal care, delay in reaching hospital, and greater severity of illness.

Airway problems in pregnancy.

Obstetric anesthesia is considered to be a difficult, high-risk practice that exposes the anesthesiologist to increased medicolegal liability. Anesthetic management of parturient patients is a challenge, as it involves simultaneous care of two lives. The anesthesia practitioner has a duty to provide safe anesthetic care, including effective airway management when providing regional or general anesthesia. The potential need to manipulate the airway is perhaps the leading cause of concern among obstetric anesthesiologists.

Prophylactic acetaminophen does not prevent epidural fever in nulliparous women: a double-blind placebo-controlled trial.

OBJECTIVE: Epidural analgesia is associated with a four- to five- fold increase in noninfectious maternal fever in nulliparous women. Fever prophylaxis may safely reduce both unnecessary neonatal sepsis evaluations and the potential effect of fever on the fetus. STUDY DESIGN: We performed a randomized double-blind placebo-controlled study. Immediately after epidural placement, full-term nulliparas with a temperature of <99.5 degrees F received acetaminophen 650 mg or placebo, per rectum, every 4 hours. Tympanic membrane temperatures were measured hourly. Our power to detect an effect of acetaminophen treatment on maternal temperature over time was 90%. RESULTS: In all, 21 subjects were randomized to each arm. Treatment with acetaminophen did not impact maternal temperature curves. Fever >100.4 degrees F was identical in the acetaminophen and placebo groups (23.8%, p=1.0). Neonatal surveillance blood cultures did not reveal occult infection. CONCLUSIONS: Acetaminophen prophylaxis prevented neither maternal hyperthermia nor fever secondary to epidural analgesia, suggesting that the mechanism underlying fever does not include centrally mediated perturbations of maternal thermoregulation.

Backache, headache, and neurologic deficit after regional anesthesia.

Back pain, chemical backache, PDPH, and neurologic deficit all may be reported after regional anesthesia for childbirth. Back pain is common during pregnancy, but epidural analgesia during labor does not increase the incidence of long-term back pain. Chemical backache caused by 2-chloroprocaine is probably a result of hypocalcemic tetany of paraspinous muscles. The mechanism is presumed to be chelation of calcium by sodium bisulfite, an antioxidant present in nesacaine-MPF. PDPH after dural puncture is caused by leakage of CSF, which causes cerebral hypotension. Cerebral hypotension leads to traction on pain-sensitive intracranial structures and cerebral vasodilation. Initial therapy includes hydration, caffeine, and sumatriptan. EBP is the most effective treatment in severe PDPH. If the first EBP fails, a second blood patch can be performed. Neurologic deficits after regional anesthesia are rare. Meticulous technique and vigilance are the keystones in avoiding major neurologic complications of regional anesthesia. Rapid diagnosis and appropriate treatment are essential to optimize a successful outcome if complications do develop.

Elevated maternal and fetal serum interleukin-6 levels are associated with epidural fever.

OBJECTIVE: The study was performed to explore the evidence for a noninfectious inflammatory cause for epidural fever. STUDY DESIGN: A secondary analysis of a prospective randomized trial was performed. At epidural placement, afebrile term nulliparous women were randomized to receive acetaminophen 650 mg or placebo every 4 hours. Maternal serum was collected every 4 hours until delivery. Cord blood samples were collected at delivery. Interleukin-6 (IL-6) and interleukin-8 levels were measured using enzyme-linked immunosorbent assay techniques. Student t tests, chi(2), repeated measure analysis of variance, Pearson correlation coefficients, and linear regression modeling were used as appropriate. RESULTS: Twenty-one subjects received placebo, and 21 received acetaminophen. The rate of fever more than 100.4 degrees F was identical in the placebo and acetaminophen groups (23.8%). Maternal serum IL-6 levels before delivery were significantly higher in mothers who had a fever (596.0 vs 169.1 pg/mL, P <.001), as was the cord blood IL-6 levels of their infants (370.5 vs 99.0 pg/mL, P <.01). Linear regression modeling demonstrated that initial maternal serum IL-6, fever, and duration of epidural but not length of rupture of membranes or number of vaginal examinations were significantly associated with final maternal serum IL-6 levels. All neonatal blood cultures were negative. CONCLUSION: Epidural fever is associated with maternal and fetal inflammation in the absence of neonatal infection. Higher levels of cytokines in maternal serum suggest that the maternal compartment is the primary inflammatory source.