Labor neuraxial analgesia and breastfeeding: An updated systematic review.

INTRODUCTION: There have been numerous reports studying the effect of neuraxial analgesia on breastfeeding success, but the results are inconsistent. METHODS: We performed a literature search in various databases for studies comparing neuraxial analgesia to non-neuraxial or no analgesia. Outcomes were the percentage of women breastfeeding fully or mixed with formula. Where possible, nulliparous parturients were analyzed separately. We conducted an analysis excluding studies of serious and critical risk of bias. Odds ratios and 95% confidence intervals were calculated. RESULTS: We included 15 studies (13 observational studies, 1 secondary analysis of a randomized controlled trial, 1 case-control study) with 16,112 participants. Overall, there were 6 studies that found no difference between groups, 6 studies that showed a significantly lower incidence of breastfeeding in the neuraxial group and 3 studies finding mixed results (at some time-points statistically significant and at some time-point statistically non-significant results). In nulliparous only studies, 2 found no difference between study groups, 1 found a lower breastfeeding rate in the neuraxial group and 3 studies showed mixed results. Excluding studies with a serious and critical risk of bias, 1 study found no difference between study groups, 3 studies found a decrease of breastfeeding rates in the neuraxial group, and 1 study showed mixed results. DISCUSSION: In our review we found a high disparity in results. One reason is probably the high potential of confounding (immediate skin to skin placement, maternity leave etc.). Education programs and breastfeeding support are likely more important in determining long term breastfeeding success.

Transversus abdominis plane block compared with wound infiltration for postoperative analgesia following Cesarean delivery: a systematic review and network meta-analysis.

PURPOSE: This systematic review and network meta-analysis (NMA) compared postoperative analgesic efficacy of transversus abdominis plane (TAP) blocks with that of wound infiltration for Cesarean delivery (CD) without long-acting neuraxial opioid administration. METHODS: We sought randomized-controlled trials comparing TAP vs wound infiltration, and inactive control vs either TAP or wound infiltration. Wound infiltration included single-dose infiltration (WI), or continuous infusion via a catheter (WC). The primary outcome was 24 hr opioid consumption. Secondary outcomes included 12 and 24 hr pain scores (resting and movement), time to first analgesia request, incidence of postoperative nausea and vomiting (PONV), maternal sedation, and pruritus. We performed a NMA incorporating both direct and indirect comparisons and reported standardized mean differences and odds ratios with 95% confidence intervals for continuous and dichotomous outcomes. RESULTS: Forty-two studies were included, comprising 2,906 participants. Transversus abdominis plane blocks and WC were associated with significantly lower 24 hr opioid consumption than inactive controls, but there were no significant differences between WI and inactive controls. There was no statistically significant difference in 24 hr opioid consumption between TAP blocks and WC or WI techniques. The network ranking of treatments was TAP block, followed by WC or WI. No significant differences were shown between TAP, WC, and WI groups for 24 hr pain scores, time to first analgesia, PONV, sedation, and pruritus. Quality of evidence was moderate for most of the outcomes assessed. CONCLUSION: In the absence of long-acting neuraxial opioid after CD, single-dose TAP blocks and WC are effective opioid-sparing strategies.

RéSUMé: OBJECTIF: Cette revue systématique et méta-analyse en réseau (MAR) ont comparé l'efficacité analgésique postopératoire de blocs du plan du muscle transverse de l'abdomen (bloc TAP, Transversus Abdominis Plane) à celle d'infiltrations de l'incision chirurgicale après un accouchement par césarienne et en l'absence d'administration d'opioïdes neuraxiaux à action prolongée. MéTHODE: Nous avons examiné les études randomisées contrôlées comparant un bloc TAP à une infiltration de l'incision, et les comparateurs inactifs vs soit un bloc TAP ou une infiltration de l'incision. Les infiltrations de l'incision comprenaient des infiltrations à dose unique ou des perfusions continues via un cathéter. Le critère d'évaluation principal était la consommation d'opioïdes en 24 heures. Les critères d'évaluation secondaires comprenaient les scores de douleur à 12 et 24 h (au repos et avec mouvement), le délai jusqu'à la première demande d'analgésie, l'incidence de nausées et vomissements postopératoires (NVPO), la sédation maternelle et le prurit. Nous avons réalisé une MAR intégrant des comparaisons directes et indirectes et rapportons les différences moyennes standardisées et les rapports de cotes avec des intervalles de confiance de 95 % pour les critères d'évaluation continus et dichotomiques. RéSULTATS: Quarante-deux études ont été incluses, comprenant 2906 participantes. Les blocs TAP et les infiltrations par cathéter étaient associés à une consommation d'opioïdes en 24 heures significativement plus faible que les comparateurs inactifs, mais aucune différence significative n'a été observée entre infiltrations uniques et comparateurs inactifs. Aucune différence statistiquement significative dans la consommation d'opioïdes en 24 heures n'a été observée entre les blocs TAP et les techniques d'infiltration par perfusion continue ou unique. Le classement en réseau des traitements est : les blocs TAP, suivi par les infiltrations par perfusion continue ou unique. Aucune différence significative n'a été démontrée dans les scores de douleur à 24 h, le délai jusqu'à la première analgésie, les NVPO, la sédation et le prurit entre les groupes TAP, infiltration par perfusion continue et infiltration unique. La qualité des données probantes était modérée pour la plupart des critères évalués. CONCLUSION: En l'absence d'un opioïde neuraxial à action prolongée après un accouchement par césarienne, les blocs TAP en dose unique et les infiltrations par perfusion continue sont des stratégies efficaces pour réduire la consommation d'opioïdes.

The Effect of Intrathecal Morphine Dose on Outcomes After Elective Cesarean Delivery: A Meta-Analysis.

BACKGROUND: The intrathecal morphine dose achieving optimal analgesia for cesarean delivery while minimizing side effects has not yet been deduced. In this meta-analysis, our objective was to determine whether low- or high-dose intrathecal morphine provides acceptable duration and intensity of analgesia with fewer side effects. METHODS: A literature search (PubMed, EMBASE, MEDLINE, Scopus, Web of Science, and CINAHL) was performed to identify randomized controlled trials involving patients undergoing elective cesarean delivery under spinal anesthesia comparing low-dose (LD; 50-100 µg) morphine with higher dose (HD; >100-250 µg). The primary outcome was the time for first request for supplemental analgesia. The secondary outcomes included pain scores, morphine use, maternal side effects (vomiting and pruritus), and Apgar scores. Mean differences (MDs) and odds ratios (ORs) were calculated using random effects modeling with 95% confidence intervals (CIs). RESULTS: Eleven articles met our inclusion criteria. Four hundred eighty patients were recruited in all study groups (233 patients in the HD and 247 in the LD groups). The mean time to first analgesic request was longer (MD, 4.49 hours [95% CI, 1.85-7.13]; P = 0.0008) in the HD group compared with the LD group. Pain scores (0-100 scale) at 12 hours (MD, 2.54 [95% CI, -2.55 to 7.63]; P = 0.33) as well as morphine consumption at 24 hours (MD, 1.31 mg [95% CI, -3.06 to 7.31]; P = 0.42) were not significantly different. The incidence of nausea or vomiting (OR, 0.44 [95% CI, 0.27-0.73]; P = 0.002) and pruritus (OR, 0.34 [95% CI, 0.20-0.59]; P = 0.0001) was lower in the LD group. The incidence of Apgar scores <7 at 1 minute was not different between groups (OR, 1.11 [95% CI, 0.06-20.49]; P = 0.94). CONCLUSIONS: This meta-analysis shows that HDs of intrathecal morphine prolong analgesia after cesarean delivery compared with lower doses. The MD of 4.5 hours (95% CI, 1.9-7.1 and 99% CI, 1.0-8.2 hours) of pain relief must be balanced against the increased risk of maternal pruritus and vomiting. Results from this study can be used by clinicians to weigh the benefits and potential side effects of using HDs of intrathecal morphine for cesarean delivery.

Will the Real Benefits of Single-Shot Interscalene Block Please Stand Up? A Systematic Review and Meta-Analysis.

BACKGROUND: Interscalene block (ISB) can provide pain relief after shoulder surgery, but a reliable quantification of its analgesic benefits is lacking. This meta-analysis examines the effect of single-shot ISB on analgesic outcomes during the first 48 hours after shoulder surgery. METHODS: We retrieved randomized and quasirandomized controlled trials examining the analgesic benefits of ISB compared with none in shoulder surgery. Severity of postoperative pain measured on a visual analog scale (10 cm scale, 0 = no pain, 10 = worst pain) at rest at 24 hours was the designated primary outcome. Secondary outcomes included pain severity at rest and with motion at 2, 4, 6, 8, 12, 16, 32, 36, 40, and 48 hours postoperatively. Opioid consumption, postoperative nausea and vomiting, patient satisfaction with pain relief, and postanesthesia care unit and hospital discharge time were also assessed. RESULTS: A total of 23 randomized controlled trials, including 1090 patients, were analyzed. Patients in the ISB group had more severe postoperative pain at rest by a weighed mean difference (95% confidence interval) of 0.96 cm (0.08-1.83; P = 0.03) at 24 hours compared with no ISB, but there was no difference in pain severity beyond that point. The duration of pain relief at rest and with motion after ISB were 8 and 6 hours, respectively, with a corresponding weighed mean difference in visual analog scale pain scores (99% confidence interval) of -1.59 cm (-2.60 to -0.58) and -2.20 cm (-4.34 to -0.06), respectively, with no additional pain relief benefits beyond these points. ISB reduced postoperative opioid consumption up to 12 hours, decreased postoperative nausea and vomiting at 24 hours, and expedited postanesthesia care unit and hospital discharge. The type, dose, and volume of local anesthetic used did not affect the results. CONCLUSIONS: ISB can provide effective analgesia up to 6 hours with motion and 8 hours at rest after shoulder surgery, with no demonstrable benefits thereafter. Patients who receive an ISB can suffer rebound pain at 24 hours but later experience similar pain severity compared with those who do not receive an ISB. ISB can also provide an opioid-sparing effect and reduce opioid-related side effects in the first 12 and 24 hours postoperatively, respectively. These findings are useful to inform preoperative risk-benefit discussions regarding ISB for shoulder surgery.

Anesthetic considerations for high order cesarean sections: a prospective cohort study.

BACKGROUND: In a previous retrospective study we demonstrated that perioperative complications occurred in a minority of high order repeat cesarean sections (HOR-C/S). In this prospective study we compared the incidence of complications in patients who have had four or more cesarean sections to those that had three or less. METHODS: This was a prospective, observational cohort study of parturients undergoing C/S at a single tertiary care hospital over a 1 year period. We compared the incidence of conversion from regional to general anesthesia, duration of surgery and incidence of major blood loss in HOR-C/S to control. RESULTS: We studied a total of 831 parturients, 129 underwent HOR-C/S. The incidence of conversion from regional to general anesthesia was similar in both groups (RR = 0.97, 95% CI 0.2, 4.3). The median duration of surgery was 40 min (range 10-145 min) in the HOR-C/S group and 30 min (range 10-150 min) in the control group (p < 0.001). The incidence of prolonged surgery was increased in the HOR-C/S group (RR = 3.6, 95% CI 2.4, 5.4). The incidence of intraoperative blood transfusion was higher in the HOR-C/S group (RR = 3.4, 95% CI 1.1, 10.2). CONCLUSIONS: Patients who have HOR-C/S are more likely to have prolonged surgery and require blood transfusion than controls. However, in our population, this was not associated with an increased incidence of conversion from regional to general anesthesia. Provided causes of severe hemorrhage such as abnormal placentation have been ruled out, HOR-C/S is not an absolute contraindication to regional block.

Repeated hands-and-knees positioning during labour: a randomized pilot study.

Background. Caesarean birth rates in North America continue to rise, in the absence of benefit for mothers and babies. One reason may be that hospitalized labouring women spend most of their labours in recumbent or semi-recumbent positions. Although hands-and-knees position has theoretical advantages, efforts to encourage its adoption in practice are severely hampered by the lack of compelling evidence that it is beneficial. Before a definitive, large scale trial, with spontaneous vaginal birth as the primary outcome, could be justified in terms of time, effort, and expense, several feasibility and acceptability questions had to be addressed. We aimed to enrol 60 women in a pilot study to assess feasibility and acceptability of the trial protocol, and to obtain estimates of treatment effects on method of birth and persistent back pain. Methods. We conducted a pilot study at two North American hospitals. In ten months of recruitment, 30 nulliparous women in labour at term were randomly allocated to either usual care (use of any position during labour except hands-and-knees) or to try hands-and-knees for 15 min every hour during labour. Data were collected about compliance, acceptability, persistent back pain, intrapartum interventions, and women's views of their experiences. Results. Although mean length of time from randomization to delivery was over 12 hours, only 9 of the 16 women allocated to repeated hands-and-knees used it more than twice. Two of the 14 in the usual care group used hands-and-knees once. Twenty-seven women had regional analgesia (15 in the hands-and-knees group and 12 in the usual care group). Eleven in the hands-and-knees group and 14 in the usual care group had spontaneous vaginal births. One woman (in the hands-and-knees group) had a vacuum extraction. Four women in the hands-and-knees group and none in the usual care group gave birth by caesarean section. Hourly back pain ratings were highly variable in both groups, covering the full range of possible scores. Given the low compliance with the hands-and-knees position, it was not possible to explore relationships between use of the position and persistent back pain scores. When asked to rate their overall satisfaction with their birth experiences, the hands-and-knees group's ratings tended to be lower than those in the usual care group, although 11 in the hands-and-knees group and 8 in the usual care group stated they would probably or definitely try the position in a subsequent labour. Conclusion. We concluded that we could not justify the time and expense associated with a definitive trial. However such a trial could be feasible with modifications to eligibility criteria and careful selection of suitable settings.

Case report: Rhabdomyolysis in morbidly obese patients: anesthetic considerations.

PURPOSE: We report the presentation and management of rhabdomyolysis involving shoulder girdle and upper arm muscles in a morbidly obese patient after prolonged laparoscopic surgery. CLINICAL FEATURES: A 41-yr-old morbidly obese woman presented for laparoscopic abdominal hysterectomy. She had hypertension and type II diabetes which were controlled on regular medications. She also had obstructive sleep apnea. Her clinical examination and investigations revealed no abnormality except morbid obesity (body mass index 54 kg·m(-2)) and left ventricular hypertrophy on transthoracic echocardiogram. Standard general anesthesia was administered under baseline non-invasive monitors. Succinylcholine was used to secure the airway during anesthetic induction. Surgery was performed with the patient positioned with a 15° head-down tilt, and it took six hours to complete the procedure as technical difficulty was encountered due to her body habitus. Her trachea was extubated and she was transferred to the postanesthetic care unit (PACU) without incident. In the PACU, the patient complained of severe bilateral arm pain and weakness an hour after surgery. On physical examination, she exhibited limited movement of her arms against gravity while complaining of tenderness in her shoulder girdle muscles and both arms. Clinical suspicion of rhabdomyolysis based on her signs and symptoms was confirmed by an elevated serum creatinine kinase (CK) of 18,392 IU·L(-1) and serum potassium of 5.3 mmol·L(-1). Intravenous crystalloids and mannitol were administered for 24 hr for renal protection, and her clinical symptoms and serum CK levels improved over seven days. The patient was discharged to home on the tenth postoperative day, and she continued to improve over the three-month follow-up period. CONCLUSIONS: Morbidly obese patients who undergo prolonged surgery are at risk for rhabdomyolysis, and early diagnosis and therapy are required to prevent severe complications.

The use of ultrasound for lumbar spinous process identification: A pilot study.

BACKGROUND: Clinical identification of lumbar spinous processes is inaccurate in most patients. The purpose of this study was to determine the number of patients required to train anesthesiologists in the use of ultrasound imaging to accurately identify the lumbar spinous processes. METHODS: In this pilot study, two anesthesiologists studied patients scheduled for a diagnostic computed tomography (CT) scan, including the lumbar spine. Before the CT scan, the anesthesiologist completed a systematic ultrasound scan of the lumbar spine and placed a radio-opaque marker at a designated level. The actual level was determined by a radiologist after reviewing the CT scans. The primary outcome was the number of procedures each anesthesiologist needed (by cumulative sum analysis) to be able to identify the designated spinous process 90% of the time. Secondary outcomes included the overall success rate, the magnitude of the failures (number of segments from the designated spinous process), and the incidence of spinal anomalies and their effect on reliability. RESULTS: We studied 74 patients. One anesthesiologist required 36 patients to meet reliability criteria, whereas the other required 22 patients. The overall accuracy rate was 68%. There were only two patients where the marker was placed more than one segment from the designated spinous process. The incidence of lumbar spine anomalies was 6.8% (n = 5), and 80% (n = 4) of these were associated with inaccurate marker placement. CONCLUSIONS: It is possible to use ultrasound scanning to accurately identify the lumbar spinous processes in unselected patients. This result suggests that, with appropriate training, this tool can be used to enhance the accuracy of needle placement during neuraxial techniques.

Effect of labor analgesia on labor outcome.

PURPOSE OF REVIEW: Labor is among the most painful experiences that humans encounter. Neuraxial analgesia is the most effective means of treating this pain. In this review, we discussed the effect of neuraxial analgesia on the progress of labor when compared with parenteral opioids. We then compared initiation of analgesia with a combined spinal-epidural technique (CSE) to conventional epidural analgesia. Finally we discussed the impact of neuraxial analgesia, given early in labor, compared with later administration. RECENT FINDINGS: Compared with parenteral opioids, neuraxial analgesia does not increase the incidence of cesarean section, although it is associated with a longer (approximately 16 min) second stage of labor. The incidence of operative vaginal delivery is higher in the epidural group but this may be due to indirect reasons such as changes in physician behavior. There was no difference in labor outcome when CSE was compared with low-concentration epidural analgesia, but higher concentrations may prolong labor. Early administration of neuraxial analgesia does not increase the incidence of operative delivery or prolong labor. SUMMARY: Neuraxial analgesia does not interfere with the progress or outcome of labor. There is no need to withhold neuraxial analgesia until the active stage of labor.

Preload or coload for spinal anesthesia for elective Cesarean delivery: a meta-analysis.

BACKGROUND: Hypotension following spinal anesthesia for Cesarean delivery is common. Fluid loading is recommended to prevent hypotension, but preload is often ineffective. In non-pregnant patients, coloading has been shown to better maintain cardiac output after spinal anesthesia. The purpose of this meta-analysis was to determine whether the timing of the fluid infusion, before (preload) or during (coload) induction of spinal anesthesia for Cesarean delivery, influences the incidence of maternal hypotension or neonatal outcome. METHODS: We retrieved randomized controlled trials that compared a fluid preload with coload in patients undergoing spinal anesthesia for elective Cesarean delivery. We graded the articles for quality of reporting (maximum score = 5) and recorded the incidence of hypotension, lowest blood pressure, the incidence of maternal nausea and vomiting, umbilical cord pH, and Apgar scores. We combined the results using random effects modelling. RESULTS: We retrieved eight studies comprised of 518 patients. The median quality score for the published studies was three. The incidence of hypotension in the coload group was 159/268 (59.3%) compared with 156/250 (62.4%) in the preload group (odds ratio [OR] = 0.93; 95% confidence interval [CI] 0.54-1.6). There were no significant differences between groups in any of the other outcomes. CONCLUSIONS: It is unnecessary to delay surgery in order to deliver a preload of fluid. Regardless of the fluid loading strategy, the incidence of maternal hypotension is high. Prophylactic or therapeutic vasopressors may be required in a significant proportion of patients.

Epidural analgesia for labor: Current techniques.

Epidural analgesia is an extremely effective and popular treatment for labor pain. In this review, we trace the history of the use of epidural analgesia and its refinements. We then outline the goals of treatment and methods used to attain those goals. The use of low concentrations of local anesthetics, combined with lipid-soluble opioids, does not impede the progress of labor or depress the newborn. The incidence of side effects is low. Maintenance of analgesia that allows patient control enhances patient satisfaction.

Patient-controlled epidural analgesia for labor.

Patient-controlled epidural analgesia (PCEA) for labor was introduced into clinical practice 20 yr ago. The PCEA technique has been shown to have significant benefits when compared with continuous epidural infusion. We conducted a systematic review using MEDLINE and EMBASE (1988-April 1, 2008) of all randomized, controlled trials in parturients who received PCEA in labor in which one of the following comparisons were made: background infusion versus none; ropivacaine versus bupivacaine; high versus low concentrations of local anesthetics; and new strategies versus standard strategies. The outcomes of interest were maternal analgesia, satisfaction, motor block, and the incidence of unscheduled clinician interventions. A continuous background infusion improved maternal analgesia and reduced unscheduled clinician interventions. Larger bolus doses (more than 5 mL) may provide better analgesia compared with small boluses. Low concentrations of bupivacaine or ropivacaine provide excellent analgesia without significant motor block. Many strategies with PCEA can provide effective labor analgesia. High volume, dilute local anesthetic solutions with a continuous background infusion appear to be the most successful strategy. Research into new delivery strategies, such as mandatory programmed intermittent boluses and computerized feedback dosing, is ongoing.

The effect of epidural needle type on postdural puncture headache: a randomized trial.

PURPOSE: A prospective, randomized trial in labouring parturients was undertaken to assess whether the 18G Special Sprotte epidural needle is associated with a lower incidence of accidental dural puncture (ADP) in comparison with the 17G Tuohy needle. A secondary purpose was to determine if the incidence of postdural puncture headache (PDPH ) differed between groups when ADP occurred. METHODS: Following Institutional Review Board approval 1,077 parturients requesting epidural analgesia at three tertiary obstetrical units were randomized to epidural catheter insertion with a 17G Tuohy or 18G Special Sprotte needle. Patients were followed for seven days by a blinded assessor to determine the occurrence of PDPH using standardized criteria. If postural headache or neck ache presented, an ADP was diagnosed even if cerebrospinal fluid (CSF) was not observed at insertion. This subgroup was followed daily to assess headache characteristics and response to blood patch. RESULTS: Six Tuohy group patients, and two patients in the Sprotte group were excluded. One of the six excluded in the Tuohy group had an ADP. Twenty-eight ADPs occurred, nine unrecognized by CSF visualization (1.8% Tuohy, 3.4% Sprotte, P = 0.12). The incidence of unrecognized ADPs was higher in the Sprotte group (40% Sprotte vs 20% Tuohy, P < 0.05). If ADP occurred, the incidence of PDPH was lower in the Sprotte group (100% Tuohy vs 55% Sprotte, P = 0.025). The ease of use, and user satisfaction were higher in the Tuohy group (84 +/- 17.3% Tuohy vs 68.2 +/- 25.3% Sprotte, P < 0.001). CONCLUSION: The incidence of ADP was not reduced with the Special Sprotte epidural needle in comparison with the Tuohy needle, but PDPH after ADP occurred less frequently in the Sprotte group.