Stephen H. Halpern

Obstetric epidural anaesthesia in patients with Harrington instrumentation

This fiveyear retrospective study reviews our experience with epidural obstetric analgesia in patients with previous Harrington rod instrumentation (HRI) for correction of idiopathic scoliosis. Patients were identified by the presence of an antepartum anaesthetic consultation for HRI. The anaesthetic record was examined to determine the frequency of epidural catheter insertion and any problems related to this procedure. Nine epidural insertions were attempted in the 16 patients identified. Five were uncomplicated but four were complicated by one or more of: failure to identify the epidural space, blood vessel trauma, dural puncture, failure to obtain analgesia or the need for multiple attempts before successful insertion. There were no sequelae related to epidural insertion. There were no sequelae related to epidural insertion. We conclude that patients with HRI may be offered epidural anaesthesia for labour and delivery provided that they are informed of the increased risk of complications.RésuméCette étude rétrospective revolt notre experience d’une anal gésie épidurale en obstétrique chez des patientes ayant précédemment subi une opération de Harrington. Neuf insertions de cathéter épiduralfurent tentées chez 16 patientes. Cinq furent sans complication et quatre furent compliquees par une ou plusieurs des complications suivantes: impossibilité d’identifier l’espace épidural, trauma des vaisseaux sanguins, ponction de la dure-mère, impossibilité d’obtenir de l’analgesie ou plusieurs tentatives afin d’insérer le cathéter. On conclut que les patientes ayant HRI peuvent subir une anesthésie épidurale lors du travail et de l’accouchement en autant qu’elles soient informées du risque croissant de complications.

Second stage pushing correlates with headache after unintentional dural puncture in parturients.

PurposeTo determine the association between bearing down, postdural puncture headache (PDPH) and epidural blood patch (EBP) following single 17 gauge unintentional dural puncture (UDP) in parturients.MethodsThe charts of 60 parturients identified with UDP in our institutional database during epidural placement were independently reviewed. Patients were divided into categories based on the anesthetic record: well-documented single punctures; well-documented multiple punctures; catheter-related puncture; unclear category (not clear if more than one puncture occurred or if dural puncture had occurred at all) and no evidence of durai puncture. Patients with single 17 gauge punctures were divided into those who had pushed (Group 1) and those who had not (Group 2). Group 2 patients had undergone Cesarean section before reaching second stage labour. The incidence of PDPH, EBP, and cumulative duration to delivery after UDP were compared between groups.ResultsThirty-three patients with well-documented single punctures were identified: 23 had engaged in active pushing as part of second stage labour(Group 1); 10 had not (Group 2). Seventy-four percent of Group 1 developed PDPH compared with 10% in Group 2 (P < 0.002). Fifty-seven percent of Group 1 received an EBP compared with 0% in Group 2 (P < 0.002). Increasing the duration of pushing was associated with an increasing incidence of PDPH; the majority of women who pushed > 30 min developed headache.ConclusionsAn increased incidence of PDPH and EBP after UDP occurs in women bearing down in 2nd stage labour when compared with those who never pushed. There was also an association between the cumulative duration of bearing down and the incidence of PDPH.RésuméObjectifDéterminer l’association qui existe entre les efforts expulsifs, les céphalées postponction durale (CPPD) et le colmatage sanguin épidural (CSE) à la suite d’une seule brèche durale accidentelle (BDA) au moyen d’un aiguille de calibre 17 chez des parturientes.MéthodeOn a révisé séparément 60 dossiers qui présentaient des BDA pendant la mise en place de l’aiguille épidurale. On a réparti les parturientes selon le protocole anesthésique: des ponctions uniques vérifiées; des ponctions multiples vérifiées; des ponctions avec cathéters; une catégorie imprécise, si plus d’une ponction a été réalisée ou si la ponction durale s’est produite à chaque essai; aucune preuve de ponction durale. Les patientes qui n’ont eu qu’une ponction avec une aiguille de calibre 17 ont été réparties en deux groupes: celles qui ont poussé (Groupe 1) et celles qui n’ont pas poussé (Groupe 2), ayant subi une césarienne avant que le travail n’en soit à la période d’expulsion. L’incidence de CPPD et de CSE et le temps entre la naissance et la BDA ont fait l’objet de comparaisons intergroupes.RésultatsTrente-trois patientes n’avaient reçu qu’une seule ponction: 23 s’étaient engagées à pousser activement pendant la phase d’expulsion du travail (Groupe 1); 10 ne poussaient pas (Groupe 2). Soixante-quatorze pour cent des patientes du Groupe 1 et 10 % du Groupe 2 ont souffert de CPPD (P < 0,002). Cinquante-sept pour cent des patientes du Groupe 1 et 0 % du Groupe 2 ont reçu un CSE (P < 0,002). L’incidence de CPPD a augmenté avec le temps des efforts expulsifs; la majorité des femmes qui ont poussé > 30 min ont eu des céphalées.ConclusionUne plus grande incidence de CPPD et de CSE a suivi la survenue d’une BDA chez des parturientes qui ont poussé à la période d’expulsion du travail comparées aux femmes qui ont subi une césarienne. L’incidence des CPPD est aussi liée au temps des efforts expulsifs.

Spinal subdural haematoma in a parturient after attempted epidural anaesthesia

We report a case of spinal subdural haematoma with neurological deficit in a 36-yr-old woman following Caesarean section for severe preeclampsia and placental abruption. She had been taking chronic trifluoperazine treatment for depression. Her activated partial thromboplastin time (aPTT) was 49 sec (normal = 26–36) but all other tests of coagulation were normal. Epidural anaesthesia was attempted but, despite a negative test dose, injection of local anaesthetic resulted in a generalized seizure and general anaesthesia was induced. Seventy-two hours after delivery, she was found to have bilateral leg weakness, urinary incontinence, absent rectal sphincter tone and asymmetrical leg reflexes. The diagnosis of spinal haematoma was confirmed by magnetic resonance imaging. She underwent emergency laminectomy and made a full neurological recovery.RésuméNous rapportons un cas d’hématome sous-dural rachidien avec déficit neurologique chez une femme de 36 ans, après une césa-rienne pour éclampsie sévère et décollement prématuré d’un placenta normalement inséré. La patiente suivait un traitement de longue durée à la trifluopérazine pour dépression. Son temps de céphaline activé (aPTT) est de 49 sec (N = 26–36) mais tous les autres tests de coagulation sont normaux. Une anesthésie épidurale mise en marche mais, malgré une dose-test négative, l’injection de l’anesthésique local provoque une crise convulsive. Une anesthésie générale est réalisée. Soixante-douze heures après la naissance on constate une faiblesse bilatérale des jambes, une incontinence urinaire, une absence du tonus du sphincter anal et des réflexes asymétriques aux membres inférieurs. Le diagnostic d’hématome sous-dural rachidien est confirmé par le cliché de résonnance magnétique nucléaire. Elle subit une laminectomie en urgence, suivie d’une récupération neurologique complète.

Measurement of Methemoglobin after EMLA® Analgesia for Newborn Circumcision

A statistically significant (p = 0.049) increase in methemoglobin (MetHb), which did not exceed normal values, was noted 8 h after application of 1 g of EMLA (Eutectic Mixture of Local Anesthetics) to the foreskin of 10 normal newborns to reduce pain associated with circumcision. The highest MetHb concentration observed was 3 g/l (toxic > 50 g/l). No infant showed clinical signs of methemoglobinemia. We conclude that EMLA is safe to use as a local anesthetic in term neonates.

Epidural morphine vs hydromorphone in post-Caesarean section patients

PurposeThe purpose of this randomized controlled double blind study was to compare the efficacy of pain relief and the side effects of epidural hydromorphone and morphine in postCaesarean patients.MethodsIn all patients, epidural anaesthesia was induced using carbonated lidocaine 2% with 1:200,000 epinephrine and 50μg fentanyl, given in incremental doses. Patients in Group 1 (n = 24) received 0.6 mg hydromorphone and patients in Group 2 (n = 22) received 3 mg morphine after delivery of the infant. Pain, pruritus and nausea were measured using a visual analog scale (at times: baseline, on admission to the recovery room, 3, 6, 12, 18 and 24 hr postoperatively), by the number of requests for additional medications and by an overall satisfaction score.ResultsThere was no difference between the groups in pain relief or in the incidence and severity of side effects. Pruritus was more pronounced within the first six hours in Group 1 and at 18 hr in Group 2.ConclusionHydromorphone provides no clinical benefit over epidural morphine for post operative analgesia following Caesarean section.RésuméObjectifL’objectif de cette étude aléatoire et en double aveugle était de comparer l’efficacité du soulagement et les effets secondaires produits par l’administration épidurale d’hydromorphone avec celle de la morphine après la césarienne.MéthodesL’anesthésie épidurale a été induite chez toutes les patientes avec de la lidocaïne carbonatée à 2% adrénalinée à 1:200000 et fentanyl 50 μg, administrés en doses fractionnées. Après l’accouchement, les patientes du groupe 1 (n = 24) ont reçu 0,6 mg d’hydromorphone et les patientes du groupe 2 (n = 22), 3 mg de morphine. La douleur, le prurit et la nausée ont été évalués sur une échelle visuelle analogique (aux instants suivants: ligne de base, à l’admission à la salle de réveil, 3, 6, 12, 18 et 24 h après l’opération), d’après le nombre de doses d’analgésiques complémentaires et un score de satisfaction générale.RésultatsIl n’y a pas eu de différence entre les groupes au regard du soulagement de la douleur et de l’incidence et la gravité des effets secondaires. Le prurit était plus marqué pendant les six heures initiales dans le groupe 1 et à la dixhuitième heure dans le groupe 2.ConclusionCliniquement, l’hydromorphone n’est pas supérieure à la morphine épidurale pour l’analgésie postopératoire de la césarienne.

HIV Infection in the Parturient

As the incidence of AIDS continues to increase in the female population, there will be more cases of HIV-positive women in the obstetric suite requiring anesthesia services. Many may be asymptomatic, but there will be patients with active opportunistic infections and malignancies who may or may not have been treated. The impact of both the disease AIDS and the drugs used to treat it on anesthetic technique can be significant. Hematological, neurological, respiratory, and immune dysfunction can be expected in a significant proportion of these women. Universal precautions should be utilized for all deliveries regardless of known HIV status. The ubiquitous presence of blood and amniotic fluid during labor and delivery mandate the use of gloves, gowns, and eye protection in the obstetric suite to avoid transmission of HIV to health care workers. Transmission to the newborn during delivery can be minimized by avoidance of skin and mucous membrane trauma and careful removal of secretions and blood. Infected parturients should be carefully assessed for neurological and hematological dysfunction prior to the use of regional anesthesia, and anesthesiologists must be aware of the potential toxicities of therapeutic drug treatment and their impact on anesthesia.

Quality and retrieval of obstetrical anaesthesia randomized controlled trials

PurposeRandomized controlled trials (RCTs) are suitable for meta-analysis and systematic reviews provided they are of high quality and are easy to retrieve. We determined these attributes of RCTs in obstetrical anaesthesia in a sample of available journals that are indexed in MEDLINE.SourceRandomized controlled trials published between January 1985 and December 1994 in seven anaesthetic and three obstetric journals were identified by a MEDLINE search, and by handsearch of the same journals. Each RCT was assigned a quality score by a blinded rater using a reliable and validated scale. The quality of each RCT was described and compared over time and by journal. The comparative yield of MEDLINE and handsearch was evaluated.Principal findingsThree hundred and forty RCTs were retrieved by MEDLINE and handsearch. Two hundred and twenty seven (65%) were identified by the MEDLINE search and 333 by the handsearch (98%). The median quality score was 3/5. There was no difference in score over time.Anesthesiology had the highest median score.Anaesthesia had the lowest (P < 0.05).ConclusionsCare must be taken when reviewing obstetrical anaesthesia research. Strategies in addition to a MEDLINE search must be used to identify RCTs since more than one third were missed using MEDLINE alone. Poor quality RCTs are more likely to be biased in favour of a new treatment. Therefore, to increase the validity of reviews sensitivity analyses based on quality should be done.RésuméObjectifLes épreuves aléatoires avec contrôles (EAC) se prêtent bien à la méta-analyse et aux survols systématiques en autant qu’ils sont de bonne qualité et faciles à récupérer. Les auteurs ont déterminé les caractéristiques des EAC en anesthésie obstétricale sur un échantillon de revues indexées dans MEDLINE.SourcesLes épreuves aléatoires avec contrôles publiées entre janvier 1985 et décembre 1994 dans sept revues d’anesthésie et trois revues d’obstétrique étaient identifiés au cours d’une recherche dans MEDLINE et par une recherche visuelle des mêmes revues. Un évaluateur neutre assignait un score de qualité à l’aide d’une échelle fiable et validée. La qualité de chaque EAC était vérifiée et comparée relativement au moment de sa parution et de son origine. La compilation obtenue grâce à MEDLINE était comparée au recueil visuel.Constations principalesII faut être prudent quand on analyse la recherche en anesthésie obstétricale. Comme plus du tiers des EAC a été omis dans MEDLINE, on doit aussi rechercher ailleurs. Les EAC de qualité médiocre sont susceptibles d’afficher un biais en faveur d’un nouveau traitement. Dès lors, pour augmenter la validité des analyses des articles de révision, il faut effectuer des analyses de sensibilité basées sur la qualité.

Uterine incision and maternal blood loss in preterm caesarean section

SummaryThe purpose of this study was to compare maternal blood loss, as reflected by the perioperative changes in haemoglobin (Hgb), the incidence of severe bleeding (estimated blood loss >1000 ml) at operation, and the need for blood transfusion, between patients who had classical caesarean section (CCS) and lower segment caesarean section (LSCS) at 34 weeks gestation or less. The data from 31 women delivered by CSS between 25 and 34 weeks gestation were compared, in a retrospective case-control fashion, to another 31 women delivered by LSCS. Patients were matched for gestational age at delivery, the type of anaesthesia, and the prior use of tocolytic therapy. Excluded from the study were patients who had an antepartum haemorrhage or placenta praevia. There was a significantly greater reduction in maternal Hgb and an higher incidence of severe bleeding in the CSS group compared to the LSCS group (P<0.05). The results of this study suggest that for preterm caesarean sections, the classical incision is associated with increased blood loss compared to the lower segment incision.

The development of a maternal satisfaction scale for caesarean section.

Satisfaction has become an important outcome measure. The purpose of this study was to develop a valid, reliable maternal satisfaction scale for women undergoing caesarean section. After Research Ethics Board approval, each patient gave verbal consent. To ensure face validity, patients were interviewed before and after caesarean section. Interviewing until no new items were generated ensured content validity. A draft scale using a 7 point Likert scale was given to 115 patients. Items endorsed by less than 15% of patients were deleted. Item-total correlations, principal component and factor analysis were performed and items in factors with less than three items or complex loadings excluded. Correlating the new scale to a Visual Analogue Scale (VAS) for satisfaction assessed construct validity. Reliability, as measured by internal consistency, was tested using Cronbachs alpha. Twenty-five women were interviewed for item generation. Patients were both nulliparous and multiparous and all received regional anaesthesia for elective or non-emergent caesarean section. Six items of the 33 on the draft scale were excluded because of lack of endorsement. Five items were excluded after principal component and factor analysis and two after item-total correlations. The correlation between the scale total and the VAS was 0.48. Cronbachs alpha was 0.82 for the total scale. Maternal sense of control was the item most related to satisfaction. This scale provides more detailed information than a simple VAS. In the population studied, this tool was found to be a valid and reliable method for assessing maternal satisfaction in women undergoing non-emergent caesarean section.

Epidural anaesthesia for Caesarean section in patients with active recurrent genital herpes simplex infections: a retrospective review

The safety of epidural anaesthesia in patients with active, recurrent genital herpes simplex (HSV) infections is controversial. We reviewed the sixyear experience of the use of epidural anaesthesia in this patient population in two institutions. Eightynine parturients with active genital HSV were administered epidural anaesthesia for Caesarean section. No patient suffered an adverse outcome related to either the anaesthetic or the virus. The theoretical risks of regional anaesthesia in the parturient with active herpes genitalis are reviewed. We conclude from available data that the risk of an adverse outcome is small and does not contraindicate the use of epidural anaesthesia in patients with recurrent infection.RésuméLa sécurilé de l’anesthésie épidurale chez des patientes atteintes d’herpès génital en phase active (HSV) est controversée. On a revu l’expérience de six ans d’administration d’anesthésie épidurale chez une population de patientes dans deux institutions. Quatre-vingt-neuf patientes ayant un herpès génital actif ont subi une anesthésie épidurale pour césarienne. Aucune patiente n’a souffert d’un effet secondaire relié soil à l’agent anesthésique ou le virus. Les risques théoriques de l’anesthésie régionale chez les patientes ayant un herpès génital actif sont revus. On conclut à partir des données, disponibles que le risque d’un effet secondaire est minime et ne représente pas une contre-indication à l’utilisation de l’anesthésie épidurale chez les patientes ayant une infection herpétique génitale récurrente.