Epidural Approach Research Articles

Epidural and spinal anaesthesia in children

Summary This chapter points out the peculiarities of children and their consequences for central blocks. The determining factors in considering the anatomy are the spinal curves, the rate of formation of the CSF, and the relationships between the spinal cord, the dura and the spinal column. The physiological characteristic is the lack of haemodynamic changes, even with high blocks in infants. The need for sedation is the major psychological point. Recent investigations into pharmacology in children emphasize the importance of protein binding as well as drug interaction. Before the description of the technique, the safety rules, practical conditions and equipment are reviewed. The caudal is the most frequently performed central block in children, because of its safety and simplicity. After a description of the puncture at S5 level, a route peculiar to children (the trans-sacral route) is reported. The way to enter the lumbar epidural space (perpendicularly) and the modified Taylor route are described. The thoracic epidural approach via the caudal route is discussed before the description of the spinal block. The recent data for drugs (local anaesthetics and narcotics) and doses, and the evidence of efficiency of concentrations as low as 0.125% for bupivacaine are reported before the discussion of the indications and the contraindications. In order to better explain the interest in central blocks in children the advantages are detailed, and to prompt anaesthesiologists to better investigate these blocks, the complications are listed prior to the conclusion.

Intervertebral epidural anaesthesia in paediatric surgery: success rate and adverse effects in 650 consecutive procedures

The success rate and occurrence of adverse effects are reported in a retrospective study of 650 (99 sacral, 468 lumbar, 76 thoracic and seven cervical) paediatric epidurals performed, mostly (91%) under light general anaesthesia, by several anaesthetists. Seventeen‐gauge Tuohy and 20‐gauge (Potts‐Cournand® and Tuohy) needles were used. Anaesthetic solutions used were 1% lignocaine, 0.5% bupivacaine and a mixture of equal volumes of 0.5% bupivacaine with either 1% lignocaine or 1% etidocaine, all containing 1:200 000 adrenaline. The epidural space was identified by loss‐of‐resistance technique (LORT) with normal saline, air or CO2. Up to five attempts were occasionally necessary. LORT using fluid resulted in more subarachnoidal penetrations than the LORT using air (P < 0.05) which was easy and reliable but produced patchy anaesthesia (‘painful gaps') in 4.2% of patients. CO2‐LORT was as easy and reliable as air‐LORT and did not result in painful gaps. Lateral and mid‐line insertion routes were equally suitable whatever the level of approach. Twenty‐gauge needles, especially Tuohy needles, resulted in significantly less dural punctures in young children. The spread of the local anaesthetic correlated with the volume injected and the height of the epidural approach. Epidural anaesthesia had little haemodynamic effects. Administration of epidural morphine improved the duration of postoperative pain relief but undesirable effects occurred in up to 50% of patients. Low doses of naloxone (2–5 μg?kg−1.h−1) counteracted most adverse effects, avoiding urinary retention and delayed apnoea. Anaesthetists and residents without experience in paediatric anaesthesia had a good success rate in performing the techniques (under supervision of an experienced anaesthetist). At the same time, experience in regional anaesthesia would significantly boost the confidence of the anaesthetist in managing such cases. The authors recommend using CO2 instead of air in the LORT.

The Lumbosacral Epidural Block: A Modified Taylor Approach for Abdominal Urologic Surgery in Children

We describe the lumbosacral epidural approach in 97 children undergoing abdominal urologic surgical procedures. Due to the rudimentary spinous process of the first sacral vertebra and the less prominent sacral angle, an appropriate upward inclination of the Tuohy needle in the midline is always possible in infants and small children. A catheter was easily inserted in every case and the technique was shown to be useful and safe for providing adequate intraoperative and postoperative pain control.

Combined infratemporal epidural and medial triangle approachによる脳底動脈先端部動脈瘤の手術

Surgical techniques for a combined infratemporal epidural and medial triangle approach to basilar tip aneurysms consists of 1) an orbitozygomatic frontotemporal craniotomy, 2) an infratemporal epidural approach in order to expose the nerve sheathes of the IInd and Ist divisions of the trigeminal nerve and the medial half of the gasserian ganglion, 3) a pterional transsylvian approach for opening the superior wall of the cavernous sinus via the medial triangle and 4) unveiling the cavernous sinus medial to the IInd division of the trigeminal nerve.Seventeen cases of ruptured basilar tip aneurysms which were operated on via this orbitozygomatic infratemporal transcavernous approach were divided into three groups and the clinical features were reviewed. The fact that out of 4 cases in the early-operation group only one case showed good operative result seems to be attributed to the serious original Hunt and Kosnik Grade of the patients. All 3 cases with Hunt and Kosnik Grades I and II in the relatively early-stage operation group (operated on between Day 6 and Day 10) were good postoperatively. The operative result of 6 out of 8 cases with Grade I or II in the delayed-operation group was good. Conclusion: 1. This transcavernous approach seems to be the preferable approach to the basilar tip aneurysm in the early stage, with several advantages such as 1) wide exposure of the operative field, 2) the shortest possible distance with only slight retraction of the temporal tip with its dura mater, and 3) no division of the Sylvian vein and the spheno-parietal sinus running within the temporal dura propria. 2. Clipping of the basilar tip aneurysm being located either in higher or lower position can be performed successfully without retracting the carotid artery and its tributaries.

Circulatory responses to epidural blockade of treated and untreated hypertensive patients.

The circulatory effects of epidural blockade were studied in 82 hypertensive patients. To compare the circulatory responses to epidural blockade between treated and untreated hypertensive patients, patients were divided into 60 treated and 22 untreated hypertensive patients groups, and to confirm the magnitude of hemodynamic changes according to the segment of epidural approach, each group was then subdivided into 3 groups as cervical, thoracic and lumbar. The blood pressure and the pulse rate were measured before and after establishment of epidural blockade. The baseline blood pressure of untreated group was significantly higher than that of treated one (P < 0.05), but there was no difference between two groups in the initial pulse rate. At 20 min after meperidine administration to epidural space, blood pressure drop was more pronounced in untreated thoracic subgroup than in treated one (P < 0.05), but there was no significant difference in blood pressure drop between treated and untreated groups of cervical and lumbar blockade. Regarding the pulse rate change, there was no significant difference between treated and untreated cases of all the subgroups. The rate of fluid load required to maintain the adequate blood pressure in the first 20 min of epidural blockade was more in treated than in untreated cases of cervical subgroup. During surgery the administration of vasopressor agents was more frequently required to maintain blood pressure in treated and untreated thoracic subgroups, while the administration of vasodilator agents was more frequent in treated and untreated cases of cervical and thoracic subgroups. The incidence of rebound hypertension was relatively high in untreated cervical and thoracic subgroups as compared to treated ones.

Epidural and intrathecal narcotics.

Administration in acute pain The effectiveness of epidural and intratheca] narcotic analgesia is well proven. Despite its definite advantages over other methods, adverse effects presently limit its use and consequently it should be used in selected cases.75,92,93 Certain conditions should be met before the administration of epidural and intrathecal analgesia and its mode of administration should be based on our actual knowledge. The epidural approach appears to be the best with regard to cost-benefit ratio and unless contraindicated should be preferred to the intrathecal approach.70 Thus this is the approach that we propose (Table V). Obstetrical analgesia, although theoretically interesting93 has been ruled out during labour, for the time being. Beta-endorphin could eventually be used in obstetrics.94