An observational pilot study of a novel loss of resistance syringe for locating the epidural space.

BACKGROUND: The EpiFaith® syringe is a novel loss-of-resistance syringe that utilizes a spring-loaded plunger that automatically moves forward within the syringe when there is a loss of resistance. We evaluated the syringe in a clinical setting among a cohort of pregnant women receiving neuraxial labor analgesia. METHODS: In a non-randomized observational study, four anesthesiologists used the EpiFaith® syringe 10 times each while placing epidural catheters for labor analgesia. The anesthesiologists scored each placement on an 11-point Likert scale (-5 = absolutely worse, 0 = the same, and 5 = absolutely better than using their regular loss-of-resistance syringe technique). RESULTS: All 40 neuraxial placements correctly located the epidural space. Air was used in the syringe in 35 of the 40 cases. In 50%, 27.5% and 22.5% of cases the anesthesiologists reported that using the EpiFaith® syringe was better than, the same as, or worse than using their regular syringe, respectively. There were no inadvertent dural punctures. CONCLUSIONS: This feasibility study found that three of the four anesthesiologists scored the EpiFaith® syringe as better or the same as using their regular loss-of-resistance syringe. More extensive studies are required to determine if the EpiFaith® syringe reduces adverse outcomes such as unintentional dural punctures.

Impact of intra-operative dexamethasone after scheduled cesarean delivery: a retrospective study.

BACKGROUND: Dexamethasone is an effective analgesic and anti-emetic in patients undergoing many surgical procedures but its effects on pain after cesarean delivery are poorly studied. The aim of this study was to evaluate if routine intra-operative administration of dexamethasone improved analgesia and decreased postoperative nausea and vomiting after scheduled cesarean delivery. METHODS: Electronic medical record data for scheduled cesarean deliveries performed under neuraxial anesthesia, before and after a practice change that introduced the routine use of intravenous dexamethasone 4 mg, were obtained. Patients were analyzed based on whether they received routine care (n=182) or also received dexamethasone (n=187). The primary outcome was time to first opioid use. Secondary outcomes included postoperative opioid consumption, pain scores, incidence and treatment of postoperative nausea and vomiting, satisfaction and length of stay. RESULTS: There was no significant difference between groups in median time to first postoperative opioid administration (15.8 [3.4-48.0] h routine care vs 14.7 [3.2-38.8] h routine care plus dexamethasone, P=0.08). There were no significant differences in any secondary outcomes. CONCLUSIONS: This impact study involving more than 360 patients suggests that routine administration of intra-operative intravenous dexamethasone 4 mg does not provide additional analgesic benefit after scheduled cesarean delivery, in the context of a multimodal postoperative analgesic regimen. Studies are required to determine if a larger dose or repeated administration influence postoperative analgesia or side effects, or whether certain subsets of patients may benefit.

Obstetric interventions and maternal morbidity among women who experience severe postpartum hemorrhage during cesarean delivery.

BACKGROUND: Compared to vaginal delivery, women undergoing cesarean delivery are at increased risk of postpartum hemorrhage. Management approaches may differ between those undergoing prelabor cesarean delivery compared to intrapartum cesarean delivery. We examined surgical interventions, blood component use, and maternal outcomes among those experiencing severe postpartum hemorrhage within the two distinct cesarean delivery cohorts. METHODS: We performed secondary analyses of data from two cohorts who underwent prelabor cesarean delivery or intrapartum cesarean delivery at a tertiary obstetric center in the United States between 2002 and 2012. Severe postpartum hemorrhage was classified as an estimated blood loss ≥1500mL or receipt of a red blood cell transfusion up to 48h post-cesarean delivery. We examined blood component use, medical and surgical interventions and maternal outcomes. RESULTS: The prelabor cohort comprised 269 women and the intrapartum cohort comprised 278 women. In the prelabor cohort, one third of women received red blood cells intraoperatively or postoperatively, respectively. In the intrapartum cohort, 18% women received red blood cells intraoperatively vs. 44% postoperatively (P<0.001). In the prelabor and intrapartum cohorts, methylergonovine was the most common second-line uterotonic (33% and 43%, respectively). Women undergoing prelabor cesarean delivery had the highest rates of morbidity, with 18% requiring hysterectomy and 16% requiring intensive care admission. CONCLUSION: Our findings provide a snapshot of contemporary transfusion and surgical practices for severe postpartum hemorrhage management during cesarean delivery. To determine optimal transfusion and management practices in this setting, large pragmatic studies are needed.

Programmed intermittent epidural boluses for maintenance of labor analgesia: an impact study.

INTRODUCTION: The aim of this impact study was to compare the analgesic efficacy and side effect profile of programmed intermittent epidural boluses (PIEB)+patient-controlled epidural analgesia (PCEA) to continuous epidural infusion (CEI)+PCEA for maintenance labor analgesia after the introduction of PIEB at our institution. METHODS: We conducted a retrospective analysis after replacing the background CEI with PIEB for our labor PCEA. Pre-change pump settings were CEI 12mL/h with PCEA (12mL bolus, lockout 15min); PIEB settings were a 9mL bolus every 45min with PCEA (10mL bolus, lockout 10min). We compared medical records of all women receiving epidural or combined spinal-epidural labor analgesia for vaginal delivery for two months before PIEB implementation to a two-month period of PIEB utilization following a five-month introductory familiarization period. The primary outcome was the proportion of women requiring rescue clinician boluses. RESULTS: Fewer patients in the PIEB group required rescue clinician boluses compared to the CEI group (12% vs. 19%, P=0.012). Time to first rescue bolus request and total bolus dose were not different. Peak (median [IQR]) pain scores were 2[0-5] with CEI and 0[0-4] with PIEB. There was no difference in instrumental delivery rates. CONCLUSIONS: Using PIEB compared to CEI as the background maintenance epidural analgesia method in conjunction with PCEA reduced the number of women requiring clinician rescue boluses while providing comparable labor analgesia. The findings of this clinical care impact study confirm the results of randomized controlled studies and suggest PIEB may be a preferable technique to CEI for the maintenance of labor analgesia.

Scheduled acetaminophen with as-needed opioids compared to as-needed acetaminophen plus opioids for post-cesarean pain management.

BACKGROUND: Combination opioid-acetaminophen drugs are commonly used for pain management after cesarean delivery. The aim of this study was to determine if scheduled acetaminophen decreases opioid use compared to as-needed combination acetaminophen-opioid administration. METHODS: We performed a retrospective chart review of women who underwent cesarean delivery before and after a clinical practice change. All patients received spinal anesthesia containing intrathecal morphine 200µg and scheduled non-steroidal anti-inflammatory drugs for 48h postoperatively. The first group (As-Needed Group, n=120) received combination oral opioid-acetaminophen analgesics as needed for breakthrough pain. The second group (Scheduled Group, n=120) received oral acetaminophen 650mg every 6h for 48h postoperatively with oral oxycodone administered as needed for breakthrough pain. The primary outcome was opioid use, measured in intravenous morphine mg equivalents, in the first 48h postoperatively. RESULTS: The Scheduled Group used 9.1±2.1mg (95% CI 5.0-13.2) fewer intravenous morphine equivalents than the As-Needed Group (P <0.0001) over the study period. Fewer patients in the Scheduled Group exceeded acetaminophen 3g daily compared to the As-Needed Group (P=0.008). Pain scores were similar between study groups. CONCLUSIONS: After cesarean delivery, scheduled acetaminophen results in decreased opioid use and more consistent acetaminophen intake compared to acetaminophen administered as needed via combination acetaminophen-opioid analgesics, without compromising analgesia.

Preferred spoken language mediates differences in neuraxial labor analgesia utilization among racial and ethnic groups.

INTRODUCTION: The aims of this study were to assess racial/ethnic disparities for neuraxial labor analgesia utilization and to determine if preferred spoken language mediates the association between race/ethnicity and neuraxial labor analgesia utilization. METHODS: We performed a retrospective cohort study of 3129 obstetric patients who underwent vaginal delivery at a tertiary care obstetric center. Bivariate analyses and multivariate logistic regression models were used to assess the relationships between race/ethnicity, preferred spoken language and neuraxial labor analgesia. RESULTS: Hispanic ethnicity (adjusted OR 0.77, 95% CI 0.61-0.98) and multiparity (adjusted OR 0.59, 95% CI 0.51-0.69) were independently associated with a reduced likelihood of neuraxial labor analgesia utilization. When preferred spoken language was controlled for, the effect of Hispanic ethnicity was no longer significant (adjusted OR 0.84, 95% CI 0.66-1.08) and only non-English preferred spoken language (adjusted OR 0.82, 95% CI 0.67-0.99) and multiparity (adjusted OR 0.59, 95% CI 0.51-0.69) were associated with a reduced likelihood of neuraxial labor analgesia utilization. CONCLUSIONS: This study provides evidence that preferred spoken language mediates the relationship between Hispanic ethnicity and neuraxial labor analgesia utilization.

Analgesic and sympatholytic effects of low-dose intrathecal clonidine compared with bupivacaine: a dose-response study in female volunteers.

BACKGROUND: A wide range of doses has been suggested for intrathecal clonidine, but no dose-ranging study has examined analgesic effects below 100 µg. The primary aim of this volunteer study was to assess the dose vs analgesic effect relationship for doses of intrathecal clonidine below 100 µg. METHODS: After IRB approval and signed informed consent, 11 healthy female volunteers participated in this randomized, double-blinded, cross-over study using a dose-ranging sparse-sampling technique. Participants received intrathecal clonidine (doses 0-100 µg; n=10) and intrathecal bupivacaine (doses 0-8.8 mg; n=9) on separate study days. At baseline, 30, and 60 min from drug administration, experimental heat pain tolerance was assessed at both a lumbar and a cranial dermatome. Heat and cold perception thresholds were assessed at the same time intervals. Heart rate (HR), arterial pressure, and forearm-finger and toe-leg cutaneous temperature gradients (Tfinger-arm and Ttoe-leg) were used as measures of sympatholysis. RESULTS: Both intrathecal clonidine and bupivacaine caused significant, dose-dependent analgesic effects at the leg but not the head. Significant analgesia to experimental heat pain was detected above 25 µg clonidine and 3 mg bupivacaine. Administration of bupivacaine but not clonidine resulted in a significant dose-related decrease in HR and Ttoe-leg; neither drug caused dose-related sympatholytic effects in the doses used. CONCLUSIONS: After 50 µg clonidine or 5 mg bupivacaine, the heat pain tolerance increased by ∼1°C, similar to the analgesic effect of 5 mg epidural morphine or 30 µg epidural fentanyl in previous studies using this experimental heat pain model. Our results provide additional data for rational dose selection of intrathecal clonidine.

Peripartum outcomes and anaesthetic management of parturients with moderate to complex congenital heart disease or pulmonary hypertension*.

We performed a retrospective cohort analysis of pregnancies among women with moderate to complex congenital heart disease or pulmonary hypertension over a 12-year period, resulting in a cohort of 107 cases in 65 women. Neuraxial analgesia or anaesthesia was provided in 84%, 89% and 95% of spontaneous vaginal, operative vaginal and caesarean deliveries, respectively. The caesarean delivery rate was 43% compared to our institution average of 27% over the same period (p = 0.02), and 38% had operative vaginal deliveries compared to a 10.5% institution rate (p < 0.01). Invasive monitoring was used in 28% of all deliveries. There were one maternal and two neonatal deaths. This study provides detailed anaesthetic and peripartum management of women with congenital heart disease, a patient population in whom evidence-based practice and data are largely lacking. We observed a predominance of neuraxial anaesthetic techniques, increased caesarean and operative delivery rates, and favourable maternal and neonatal outcomes. Multicentre studies and registries to compare anaesthetic and obstetric management strategies further and delineate risk factors for adverse outcomes are required.

Intrathecal morphine 100 and 200 µg for post-cesarean delivery analgesia: a trade-off between analgesic efficacy and side effects.

INTRODUCTION: Intrathecal morphine is highly effective for post-cesarean analgesia; however, the optimal dose is yet to be established. The aim of this study was to compare analgesia and side effects after a change in institutional practice to give 200 µg rather than 100 µg. METHODS: We conducted a retrospective chart review of 241 patients who had an elective cesarean delivery and received either 100 or 200 µg of intrathecal morphine. The primary outcome variables were mean and peak verbal pain scores (0-10) and analgesic use (milligram-morphine equivalents). Postoperative administration of antiemetics, antipruritics and episodes of nausea or vomiting were recorded. Data are reported as mean±SD or percentages with P<0.05 considered statistically significant. RESULTS: Women receiving intrathecal morphine 200 µg had lower pain scores and opioid use compared with morphine 100 µg. Mean verbal pain scores were 1.6±1.1 versus 2.0±1.1 (P=0.01) and peak verbal pain scores were 4.9±2.0 versus 5.6±1.8, respectively (P=0.008). The group receiving 200 µg used less opioids in the first 24 h after surgery (44±35 versus 54±35 milligram-morphine equivalents, respectively, P=0.04) and received less intravenous opioids (18% versus 30%, P=0.02). However, women receiving intrathecal morphine 200 µg had more nausea (mean number of episodes of nausea 1.9±1.3 versus 1.6±1.3, P=0.037) and used more antiemetics (52% versus 24%, P<0.0001). CONCLUSIONS: Intrathecal morphine 200 µg provided better analgesia but with more nausea compared with morphine 100 µg. Our results can be used to help guide intrathecal morphine dosing in cesarean delivery based on patient preference for analgesia versus side effects.

Subdural hematoma after an epidural blood patch.

We report the case of a 37-year-old postpartum patient who developed a contained subacute spinal subdural hematoma causing mass effect on the cauda equina and severe spinal stenosis after undergoing an epidural blood patch for postdural puncture headache. Recovery occurred following administration of oral steroids.

Intrathecal fentanyl added to bupivacaine and morphine for cesarean delivery may induce a subtle acute opioid tolerance.

BACKGROUND: Previous studies have demonstrated that the addition of intrathecal fentanyl to a spinal anesthetic for cesarean delivery improves intraoperative analgesia. However, intrathecal fentanyl may induce acute tolerance to opioids. The objective of this study was to investigate whether the addition of intrathecal fentanyl to spinal anesthesia with intrathecal morphine increases postoperative analgesic requirements and pain scores. METHODS: In this randomized, double-blinded study, 40 women having elective cesarean delivery were enrolled. Patients received spinal anesthesia with hyperbaric bupivacaine 12 mg, morphine 200 µg, and fentanyl 0, 5, 10 or 25 µg. Each patient received intravenous patient-controlled analgesia morphine for 24h postoperatively. Outcome measures included postoperative morphine usage and pain scores, as well as intraoperative pain, nausea, hypotension and vasopressor use. RESULTS: Total morphine use over the 24-h post-spinal study period was similar among the study groups (P=0.129). Postoperative pain scores were higher in patients receiving fentanyl 5, 10 and 25 µg compared to fentanyl 0 µg control group (P=0.003). CONCLUSIONS: The study results suggest that intrathecal fentanyl may induce acute tolerance to intrathecal morphine. However, because there was no difference in postoperative analgesia requirement and the difference in pain scores was small, the clinical significance of this finding is uncertain.

Non-invasive measurement of hemoglobin during cesarean hysterectomy: a case series.

Obstetric patients diagnosed with abnormal placentation (placenta accreta, increta or percreta) are at increased risk of major postpartum hemorrhage and cesarean hysterectomy. Obstetric anesthesiologists are primarily involved in intraoperative transfusion management in these cases. Hemoglobin assessment is invaluable for assisting transfusion decision-making during the acute period of obstetric hemorrhage. However, laboratory and point-of-care tests of hemoglobin concentration are time-dependent and intermittent, and do not provide a real-time assessment of change during the acute phase of blood loss. A new non-invasive hemoglobin monitor has been introduced recently, which provides real-time measurement of hemoglobin values (SpHb) using multi-wavelength pulse co-oximetry. We present a review of five patients with suspected abnormal placentation who received SpHb monitoring during cesarean hysterectomy at our institution. We discuss the potential clinical utility of non-invasive hemoglobin monitoring for pregnant patients at high risk of obstetric hemorrhage, and the potential role of SpHb in guiding transfusion therapy.

Minimum effective bolus dose of oxytocin during elective Caesarean delivery.

BACKGROUND: The aim of this study was to determine the lowest effective bolus dose of oxytocin to produce adequate uterine tone (UT) during elective Caesarean delivery (CD). METHODS: Seventy-five pregnant patients undergoing elective CD under spinal anaesthesia were randomized to receive oxytocin (0.5, 1, 3, 5 units) or placebo. UT was assessed by a blinded obstetrician as either adequate or inadequate, and using a verbal numerical scale score (0-10; 0, no UT; 10, optimal UT) at 2, 3, 6, and 9 min after oxytocin administration. Minimum effective doses of oxytocin were analysed (ED(50) and ED(95)) using logistic regression. Oxytocin-related side-effects (including hypotension) were recorded. RESULTS: There were no significant differences in the prevalence of adequate UT among the study groups at 2 min (73%, 100%, 93%, 100%, and 93% for 0, 0.5, 1, 3, and 5 units oxytocin, respectively). The high prevalence of adequate UT after placebo and low-dose oxytocin precluded determination of the ED(50) and ED(95). UT scores were significantly lower in patients receiving 0 unit oxytocin at 2 and 3 min compared with 3 and 5 units oxytocin (P<0.05, respectively). The prevalence of hypotension was significantly higher after 5 units oxytocin vs 0 unit at 1 min (47% vs 7%; P=0.04). CONCLUSIONS: The routine use of 5 units oxytocin during elective CD can no longer be recommended, as adequate UT can occur with lower doses of oxytocin (0.5-3 units).

Analgesic requirements and postoperative recovery after scheduled compared to unplanned cesarean delivery: a retrospective chart review.

BACKGROUND: Studies examining the effects of various analgesics and anesthetics on postoperative pain following cesarean delivery conventionally use the scheduled cesarean population. This study compares postoperative analgesic requirements and recovery profiles in women undergoing scheduled cesarean compared to unplanned cesarean delivery following labor. We postulated that unplanned cesarean deliveries may increase postoperative analgesic requirements. METHODS: We conducted a retrospective chart review of 200 cesarean deliveries at Lucile Packard Children's Hospital, California. We examined the records of 100 patients who underwent scheduled cesarean delivery under spinal anesthesia (hyperbaric bupivacaine 12 mg with intrathecal fentanyl 10 microg and morphine 200 microg) and 100 patients that following a trail of labor required unplanned cesarean under epidural anesthesia (10-25 mL 2% lidocaine top-up with epidural morphine 4 mg after clamping of the umbilical cord). We recorded pain scores, analgesic consumption, time to first analgesic request, side effects, and length of hospital stay. RESULTS: We found no differences in postoperative pain scores and analgesic consumption between scheduled and unplanned cesarean deliveries for up to five days postoperatively. There were no differences in treatment of side effects such as nausea, vomiting, or pruritus (P>0.05). CONCLUSION: The results indicate that women experience similar pain and analgesic requirements after scheduled compared to unplanned cesarean delivery. This suggests that the non-scheduled cesarean population may be a suitable pain model to study pain management strategies; and that alterations in pain management are not necessary for the unplanned cesarean delivery population.

Retrospective analysis of transfusion outcomes in pregnant patients at a tertiary obstetric center.

BACKGROUND: The decision to use red blood cell transfusion and/or blood products (fresh frozen plasma, platelets, cryoprecipitate) to manage obstetric hemorrhage or treat postpartum anemia is often made empirically by physicians. We performed a retrospective study to review transfusion outcomes in pregnant and postpartum patients at a large obstetric center. METHODS: A retrospective, observational study was performed of obstetric in-patients who received red blood cell transfusion and/or blood products over a one-year period. Data abstracted included transfusion data, pre-transfusion hemoglobin (Hb) and lowest recorded (nadir) Hb, and maternal and neonatal outcomes. RESULTS: During the study period, 74 patients received transfusion therapy (1.4%). Pre-transfusion and nadir Hb values were 7.6 g/dL and 7.0 g/dL respectively. Median [IQR] total red blood cells transfused were 2 units [2-3], with 41 (55%) patients receiving 1-2 units. Based on chart review, no specific indications for transfusion were identified in 25 patients (34%), and 13 patients (18%) had undetected postpartum anemia (Hb values <8.2 g/dL) at least 24h after delivery. CONCLUSION: More formal assessment and documentation of the etiologic factors associated with transfusion management in pregnant patients is advised. In addition, the identification and management of undetected postpartum anemia is underappreciated.

Hetastarch co-loading is as effective as pre-loading for the prevention of hypotension following spinal anesthesia for cesarean delivery.

BACKGROUND: Pre-loading with hetastarch decreases the incidence and severity of hypotension after spinal anesthesia for cesarean delivery. However, pharmacokinetic studies with crystalloid predict that fluid loading should be more efficacious if rapidly administered immediately after induction of spinal anesthesia. The aim of this study was to compare pre- and co-loading of hetastarch for the prevention of hypotension following spinal anesthesia for cesarean delivery. METHODS: Forty-six healthy term parturients scheduled for cesarean delivery were randomized to receive 500 mL of 6% hetastarch intravenously, either slowly before spinal anesthesia (pre-loading) or as quickly as possible immediately after spinal anesthesia (co-loading). Systolic blood pressure was maintained at or above 90% of baseline with intravenous vasopressor boluses (ephedrine 5mg/mL+phenylephrine 25 microg/mL). The primary outcome was the volume of vasopressor mix required. Secondary outcomes included blood pressure and heart rate changes, time to first vasopressor use, nausea or vomiting, and neonatal outcomes (umbilical artery and vein pH, Apgar scores). RESULTS: The pre-loading group used 3.5+/-2 mL (mean+/-SD) of vasopressor mixture compared with 3.2+/-3 mL in the co-loading group (P=0.6). There were no differences in any important maternal hemodynamic or neonatal outcome values between the two study groups. CONCLUSION: Hetastarch co-loading is as effective as pre-loading for the prevention of hypotension after spinal anesthesia for cesarean delivery. Surgery need not be delayed to allow a predetermined pre-load to be administered before induction of spinal anesthesia.

"Ultra-light" patient-controlled epidural analgesia during labor: effects of varying regimens on analgesia and physician workload.

BACKGROUND: Patient-controlled epidural analgesia (PCEA) offers many advantages over continuous epidural infusions for maintenance of labor analgesia. Some of these benefits may depend on the PCEA settings. This study evaluated several regimens for "ultra-light" (0.125%) PCEA with basal continuous infusion (CI) in labor with goals of minimizing physician interventions while providing good analgesia. METHODS: Two hundred and twenty ASA I-II women receiving epidural analgesia during active labor (cervical dilation <5 cm) were randomly assigned in a double-blind manner to four treatment groups (n=30 in each). Analgesia was maintained with a PCEA/CI pump using bupivacaine 0.0625% + sufentanil 0.35 microg/mL. PCEA settings were: group A: CI 10 mL/h, PCEA bolus 6 mL, 8-min lockout; group B: CI 10 mL/h, PCEA bolus 12 mL, 16-min lockout; group C: CI 15 mL/h, PCEA bolus 6 mL, 8-min lockout; group D: CI 15 mL/h, PCEA bolus 12 mL, 16-min lockout. RESULTS: In groups A, B, C and D, 76, 77, 75 and 85% of parturients respectively, required no physician rescue boluses. Pain scores were low and maternal satisfaction was high in all groups, with minimal differences among them. Spontaneous vaginal delivery occurred in 78% of patients overall, instrumental (forceps or vacuum) delivery in 10% and cesarean section in 12%. CONCLUSIONS: These ultra-light PCEA regimens provided excellent analgesia with minimal physician workload and a high spontaneous delivery rate. Use of moderate to high-volume, ultra-light PCEA/CI techniques should facilitate provision of labor analgesia in busy obstetric units.