M. Van de Velde

I.V. and perineural dexamethasone are equivalent in increasing the analgesic duration of a single-shot interscalene block with ropivacaine for shoulder surgery: a prospective, randomized, placebo-controlled study

BACKGROUND Interscalene brachial plexus block (ISB) provides excellent, but time-limited analgesia. Dexamethasone added to local anaesthetics prolongs the duration of a single-shot ISB. However, systemic glucocorticoids also improve postoperative analgesia. The hypothesis was tested that perineural and i.v. dexamethasone would have an equivalent effect on prolonging analgesic duration of an ISB. METHODS We performed a prospective, double blind, randomized, placebo-controlled study. Patients presenting for arthroscopic shoulder surgery with an ISB were randomized into three groups: ropivacaine 0.5% (R); ropivacaine 0.5% and dexamethasone 10 mg (RD); and ropivacaine 0.5% with i.v. dexamethasone 10 mg (RDiv). The primary outcome was the duration of analgesia, defined as the time between performance of the block and the first analgesic request. Standard hypothesis tests (t-test, Mann-Whitney U-test) were used to compare treatment groups. The primary outcome was analysed by Kaplan-Meier survival analysis with a log-rank test and Coxs proportional hazards regression. RESULTS One hundred and fifty patients were included after obtaining ethical committee approval and patient informed consent. The median time of a sensory block was equivalent for perineural and i.v. dexamethasone: 1405 min (IQR 1015-1710) and 1275 min (IQR 1095-2035) for RD and RDiv, respectively. There was a significant difference between the ropivacaine group: 757 min (IQR 635-910) and the dexamethasone groups (P<0.0001). CONCLUSIONS I.V. dexamethasone is equivalent to perineural dexamethasone in prolonging the analgesic duration of a single-shot ISB with ropivacaine. As dexamethasone is not licensed for perineural use, clinicians should consider i.v. administration of dexamethasone to achieve an increased duration of ISB.

Ten years of experience with accidental dural puncture and post-dural puncture headache in a tertiary obstetric anaesthesia department

BACKGROUND Accidental dural puncture (ADP) and post-dural puncture headache (PDPH) are important complications of obstetric regional anaesthesia. METHODS Between January 1997 and October 2006 in our tertiary obstetric referral centre 17 198 neuraxial blocks were recorded; 965 epidural, 16193 combined spinal-epidural and 40 spinal. Records of all parturients who experienced either ADP or PDPH were reviewed. RESULTS There were 89 ADPs (0.5%), 55 observed and 34 in which PDPH followed unrecognised dural puncture. Following known ADP, 28 women had epidural catheters re-sited at a different lumbar interspace and 27 had intrathecal catheters for at least 24 h. Thirty-one women developed PDPH after observed ADP; the incidence of PDPH was similar after puncture with needle and catheter, after epidural and CSE techniques, after 27- and 29-gauge pencil-point spinal needles and after spinal and epidural catheter insertion (61% vs 52%; P>0.05). All headaches presented within 72 h. A blood patch was needed in 26/55 women after known ADP and 27/34 unrecognised ADP. A repeat blood patch was needed in 8 (15%). DISCUSSION The incidence of ADP, PDPH, blood patching and repeat blood patching is similar to previous studies. Many ADPs are unrecognised during epidural insertion. CSE does not appear to increase the risk of ADP or PDPH; 29-gauge rather than 27-gauge pencil-point spinal needles conferred no benefit. Inserting the epidural catheter intrathecally did not significantly reduce the incidence of PDPH and blood patching in our series.

A multicentre trial comparing different concentrations of ropivacaine plus sufentanil with bupivacaine plus sufentanil for patient-controlled epidural analgesia in labour

Background and objective: To determine the optimal concentration of ropivacaine for bolus-only patient-controlled epidural labour analgesia, three different doses of ropivacaine were evaluated in comparison with bupivacaine in a double-blinded multicentre study. Methods: Four hundred-and-fifty labouring parturients at term in three different academic institutions were randomized to four groups receiving bupivacaine 0.125% with sufentanil 0.75 μg mL−1, ropivacaine 0.125% or 0.175% with sufentanil 0.75 μg mL−1, or ropivacaine 0.2%. After an initial bolus of 10 mL of the study solution, and once visual analogue scores (VAS) were below 30 mm, patient-controlled epidural analgesia was initiated with a bolus of 4 mL, a lockout interval of 15 min and without a background infusion. Variables studied were the quality of analgesia, incidence of side-effects, the degree of motor blockade, and the mode of delivery. Results: Bupivacaine 0.125% and ropivacaine 0.125% with sufentanil proved equally effective in providing labour analgesia without a difference in local anaesthetic consumption (48.6 ± 23 mg bupivacaine vs. 52.1 ± 38 mg ropivacaine), motor blockade or mode of delivery. Ropivacaine 0.175% plus sufentanil enhanced the quality of analgesia of the initial loading dose, whereas ropivacaine 0.2% without sufentanil increased the consumption of local anaesthetics (80.2 ± 34 mg; P < 0.05) and the degree of motor blockade. Conclusion: Despite recent studies indicating that bupivacaine and ropivacaine may not be equipotent, both local anaesthetics provided equi-effective analgesia at equal doses without a difference in side-effects.

Surgical closure of the patent ductus arteriosus and its effect on the cerebral tissue oxygenation

Aim: Surgical patent ductus arteriosus (PDA) ligation is considered after failure or contraindication of medical treatment. Till now ligation of the PDA has been associated with low morbidity and mortality although recently concerns have been raised about the possible association of ductal clipping and neurodevelopmental abnormalities later in life. By means of near‐infrared spectroscopy (NIRS), we analysed the changes in the cerebral tissue oxygenation index (TOI) and fractional tissue oxygen extraction (FTOE) at the time of clipping as well as after clipping.

Meta-analysis of the success of block following combined spinal-epidural vs epidural analgesia during labour.

Observational studies suggest that combined spinal‐epidural analgesia (CSE) is associated with more reliable positioning, lower epidural catheter replacement rates, and a lower incidence of unilateral block compared with epidural analgesia. However, evidence from high‐quality trials still needs to be assessed systematically. We performed a systematic review that included 10 randomised controlled trials comparing CSE and epidural analgesia in 1722 labouring women in labour. The relative risk of unilateral block was significantly reduced after CSE vs epidural analgesia (0.48, 95% CI 0.24–0.97), but significant between‐study heterogeneity was present (I2 = 69%, p = 0.01). No differences were found for rates of epidural catheter replacement, epidural top‐up, and epidural vein cannulation. On the basis of current best evidence, a consistent benefit of CSE over epidural analgesia cannot be demonstrated for the outcomes assessed in our review. A large randomised controlled trial with adequate power is required.

Insertion of an intrathecal catheter following accidental dural puncture: a meta-analysis

BACKGROUND Inserting an intrathecal catheter after accidental dural puncture in parturients to prevent postdural puncture headache is becoming increasingly popular. We aimed to identify relevant published articles investigating this intervention and subject data to a meta-analysis. METHODS A systematic literature search was performed, paralleled by a hand search of abstract publications. Studies that reported the dichotomous outcome parameters postdural puncture headache or need for an epidural blood patch were considered eligible. Risk ratios with 95% confidence intervals were calculated. RESULTS We identified nine reports investigating placement of intrathecal catheters after accidental dural puncture. The risk ratio for an epidural blood patch after intrathecal catheter insertion was 0.64 (95% CI 0.49-0.84, P=0.001). The risk ratio for postdural puncture headache was 0.82 (95% CI 0.67-1.01, P=0.06). DISCUSSION Inserting an intrathecal catheter significantly reduced the risk for an epidural blood patch; the incidence of postdural puncture headache was reduced but not significantly. Accidental dural puncture is a rare complication and therefore trials on intervention need to include a large number of patients which is time-consuming and costly. Intrathecal catheterisation is a promising approach for the prevention of postdural puncture headache and should be evaluated further. This intervention has additional benefits including a reduced risk of repeat dural puncture, rapid onset of action and use for anaesthesia.

Congenital high airway obstruction syndrome successfully managed with ex‐utero intrapartum treatment

Congenital high airway obstruction syndrome (CHAOS) groups together sporadically and rarely occurring malformations. When obstruction of the upper airways is complete, the condition is in theory lethal unless appropriate measures are taken. This is only possible when the diagnosis is made prenatally. Ultrasound usually reveals signs that are secondary to complete airway obstruction, including dilated trachea and main bronchi, bilateral hyperechogenic and enlarged lungs and a flattened to everted diaphragm. Ascites or hydrops may complicate the condition in utero and even lead to intrauterine fetal death. Intrinsic causes of CHAOS are stenosis or agenesis of the larynx, cricoid and/or trachea. Associated malformations need to be ruled out as laryngeal atresia has been found in association with, for example, Fraser (cryptophthalmus syndactyly) syndrome and DiGeorge developmental field defect (22q11 microdeletion). The ultrasound features described above could exceptionally be present in the case of large, bilateral microcystic congenital cystic adenomatoid malformation (CCAM), but this condition rarely involves the entire lung. Moreover, CCAM does not cause tracheobronchial dilatation. External giant fetal neck masses may also lead to airway obstruction, but these can be distinguished easily by their typical ultrasound features. Prenatal diagnosis of high airway obstruction is essential to enable organization of life-saving perinatal management. The level and extent of obstruction can be determined quite accurately prior to birth and may be of use when securing airways after birth. A perinatal ‘operation on placental support (OOPS)’ makes it possible to create surgical airways1. This includes partial abdominal delivery of the head and neck while the fetus remains attached to the placental circulation. This allows for careful laryngoscopic exploration of the upper airways and, when needed, tracheostomy. The use of OOPS for CHAOS is rare, with only three cases reported2–4. The procedure in itself, however, has become a well-established though not widely available tool in the perinatal management of obstructed airways. Bouchard et al.5 recently reported the largest single-center experience with 31 cases and operation times of up to 66 min. The majority of cases (n = 13) were for reestablishing airways after iatrogenic tracheal occlusion as a therapy for congenital diaphragmatic hernia, which prompted the use of another acronym for this operation (EXIT: ex-utero intrapartum tracheoplasty). The other cases involved a range of congenital anomalies obstructing the airways or requiring fetal surgery while on placental support. As its application widens to other anomalies and additional procedures may be part of the intervention, the acronym EXIT now covers a more generic description: ‘ex-utero intrapartum treatment’. We describe a case of CHAOS which was diagnosed prenatally in time to plan for an EXIT procedure. A 33-year-old primigravida was referred at 26 weeks’ gestation because of detection of ascites on routine ultrasound. Detailed examination revealed homogeneously echogenic lungs, dilated tracheobronchial tree and a flattened diaphragm (Figure 1). On cross-sectional view the fetal heart was subjectively small, with a cardiothoracic ratio of 0.46. In a longitudinal plane we estimated the level of obstruction at the pharynx (Figure 2). There were no associated abnormalities, except for a single umbilical artery, moderate ascites and polyhydramnios (deepest vertical pocket, 110 mm). The parents declined fetal karyotyping. Magnetic resonance imaging confirmed the diagnosis but did not provide additional information. In view of the presumptive diagnosis of obstructed airways, an EXIT procedure near term was proposed, to which the parents consented. The mother was referred and counseled at the University Hospital of Leuven (Belgium), where there is experience with EXIT for giant neck masses, as well as it being part of a program of in-utero tracheal occlusion for diaphragmatic hernia.

Effects of epidural clonidine and neostigmine following intrathecal labour analgesia: a randomised, double-blind, placebo-controlled trial

BACKGROUND The limited duration of spinal labour analgesia combined with problems associated with maintenance of epidural analgesia, have prompted the search for combinations that could prolong spinal analgesia. A randomised, double-blind trial was carried out to test the hypotheses (a) that initial spinal labour analgesia is prolonged by administering clonidine and neostigmine epidurally whilst (b) the hourly local anaesthetic consumption is reduced. METHODS Seventy labouring patients received spinal analgesia with ropivacaine and sufentanil. Fifteen minutes after spinal injection, 10 mL of study solution was administered epidurally. The study solution was plain saline or neostigmine 500 microg combined with clonidine 75 microg. Outcome parameters were duration of spinal analgesia, local anaesthetic consumption and number of patients delivering without additional epidural analgesia. RESULTS Epidural clonidine and neostigmine significantly prolonged initial analgesia: 144 (105-163) min vs. 95 (70-120) min in the placebo group and reduced hourly ropivacaine consumption: 7.5 (3.0-11.9) mg vs. 12.7 (9.6-16.9) mg. More patients in the experimental group delivered before the first request for additional analgesia (9 vs. 2). CONCLUSION Epidural administration of neostigmine 500 microg and clonidine 75 microg, following the intrathecal injection of ropivacaine and sufentanil, prolongs analgesia and reduces hourly ropivacaine consumption.

Prophylactic tranexamic acid in parturients at low risk for post-partum haemorrhage: systematic review and meta-analysis

Tranexamic acid is effective in reducing blood loss during various types of surgery and after trauma. No compelling evidence has yet been presented for post‐partum haemorrhage. A systematic literature search of relevant databases was performed to identify trials that assessed blood loss and transfusion incidence after tranexamic acid administration for post‐partum haemorrhage. The random effects model was used for meta‐analysis. Risk ratios (RRs) and weighted mean differences (WMDs) were calculated with 95% confidence intervals (CIs). Seven trials with a low risk of bias comparing tranexamic acid vs. placebo with a total of 1760 parturients were included in our systematic review and meta‐analysis. Blood loss was significantly lower after tranexamic acid use (WMD −140.29 ml, 95% CI −189.64 to −90.93 ml; P < 0.00001). Tranexamic acid reduced the risk for blood transfusions (RR 0.34, 95% CI 0.20–0.60, P = 0.0001). The incidence of transfusions in the placebo group varied between 1.4% and 33%. When omitting the two trials with the highest incidence of transfusions, the RR was no longer significant. Additional uterotonics were necessary in the placebo groups; gastrointestinal adverse events were more common after tranexamic acid use. Only four cases of thrombosis were found, two each in the tranexamic acid and control groups. Tranexamic acid effectively reduced post‐partum blood loss; the effect on the incidence of blood transfusions requires further studies. Only few trials observed adverse events including thromboembolic complications and seizures.

Remifentanil patient-controlled analgesia should be routinely available for use in labour

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