Thoracic epidural anesthesia via the lumbar approach in infants and children

Paths of thoracic epidural catheters in children undergoing the Nuss procedure for pectus excavatum repair

Purpose

To investigate the paths of thoracic epidural catheters in children, this retrospective study was performed.

Methods

We investigated 73 children aged 4 to 12 (mean ± SD 7.8 ± 2.3) years, who underwent the Nuss procedure for pectus excavatum repair under combined general and epidural anesthesia over a 5-year period at Tokyo Metropolitan Police Hospital. Following induction of general anesthesia, we inserted a radiopaque epidural catheter via the T5/6 or T6/7 interspace and advanced for 5 cm cephalad in the thoracic epidural space. We evaluated the paths of the epidural catheters on plain chest radiographs after surgery.

Results

The median level for the catheter tip location was T3 (range C6–T7), while the median number of vertebrae crossed by the catheter tips was 2.5. In most children, the catheters advanced straight for the first 2–3 cm (1–1.5 vertebrae) in the thoracic epidural space. However, they continued to advance straight in only 25 children, while they exhibited curved or coiled paths in the remaining 48. The catheter tips were located at higher levels in children with straight epidural catheter paths [median (range) T2 (C6–T4)] than in those with curved or coiled paths after the initial 2–3 cm [median (range) T4 (T2–T7)] (p < 0.0001).

Conclusions

Our findings indicate that the course of epidural catheters in children is unpredictable after the first 2–3 cm in the thoracic epidural space. Clinicians should be aware of such findings, although further studies are required for confirmation.

Caudal and epidural blocks in infants and small children: historical perspective and ultrasound-guided approaches

In infants and small children, ultrasound (US) guidance provides ample anatomical information to perform neuraxial blocks. We can measure the distance from the skin to the epidural space in the US image and can refer to it during needle insertion. We may also visualize the needle or a catheter during real-time US-guided epidural catheterization. In cases where direct needle or catheter visualization is difficult, US allows predicting successful puncture and catheterization using surrogate markers, such as dura mater displacement, epidural space widening due to drug injection, or mass movement of the drug within the caudal space. Although many experienced anesthesiologists still prefer to use conventional techniques, prospective randomized controlled trials using US guidance are providing increasing evidence of its advantages. The use of US-guided regional block will gradually become widespread in infants and children.

Caudal extradural catheterization in pediatric renal transplant and its effect on perioperative hemodynamics and pain scoring: a prospective randomized study

PURPOSE

'Hockey stick incision' used in renal transplant is large enough to cause severe postoperative morbidity especially in pediatric recipients. Although epidural analgesia is known to be effective in pain control, the resulting sympathectomy might affect hemodynamics interfering with the transplant process. In our study, we evaluated the feasibility and safety of inserting an epidural catheter to the thoracic level via the caudal route, and the effect of using epidural local anesthetics at low concentrations on hemodynamics.

METHODS

After approval from the ethical committee at Kasr Al Ainy University Hospital and consent from parents/legal guardians, sixty patients aged 3-12 years who were scheduled for renal transplant were randomly divided into two equal groups. Group I (epidural group) received continuous caudal epidural bupivacaine 0.125 % with fentanyl together with intravenous (IV) fentanyl and paracetamol. Group II (control group) received only IV fentanyl and paracetamol. Intraoperative data included heart rate (HR), mean arterial blood pressure (MAP) and central venous pressure (CVP). Postoperative variables included HR, MAP, CVP, pain score and complications.

RESULTS

Threading failure via the caudal route occurred in 6.67 % of cases. Intraoperative differences in hemodynamics and CVP were not clinically significant between groups. Postoperative HR, MAP, and CVP were generally higher in the control group. Pain control was more satisfactory and postoperative complications were less in the epidural group.

CONCLUSION

Caudal epidural anesthesia in pediatric renal transplant is a valuable addition to general anesthesia as it provides stable perioperative hemodynamics, excellent postoperative analgesia and is associated with fewer complications than narcotic-dependent analgesia.

CLINICAL TRIAL REGISTRATION NUMBER

NCT02037802.

Infant lumbar and thoracic epidurals for abdominal surgeries: cases in a paediatric tertiary institution

INTRODUCTION

There is strong evidence that epidural analgesia provides good postoperative pain relief in adults, but its use in infants is less established. In this retrospective study, we present our experience with managing infant epidural analgesia for abdominal surgeries in a tertiary paediatric institution.

METHODS

The records of 54 infants who had received a thoracic or lumbar epidural as perioperative analgesia for abdominal surgeries were included. The mean age of the infants was 6.1 (standard deviation [SD] 3.8) months and their mean weight was 6.8 kg (SD 1.8). Most (63%) had an ASA (American Society of Anesthesiologists) status of 2 and all underwent elective gastrointestinal, urogenital, hepatobiliary or retroperitoneal surgeries. 20 catheters (37.0%) were inserted in the thoracic region and 33 (61.1%) in the lumbar region.

RESULTS

A total of 52 (96.3%) catheters provided adequate intraoperative analgesia and 36 (66.7%) provided effective analgesia for the postoperative period. Active management of epidural analgesia, such as through epidural top-ups and infusion rate adjustment, was necessary to optimise analgesia in 22 (44%) of the 50 patients postoperatively. Reasons for premature catheter removal were mainly technical issues such as catheter disconnection, leakage and blockage.

CONCLUSION

Our data suggests that in experienced hands, specialised settings and active management, the success rate of epidural analgesia in infants undergoing major abdominal surgeries is high and without major incident.

Stimulating thoracic epidural placement via a lumbar approach causes significant spinal cord damage in a porcine model

BACKGROUND

Continuous thoracic epidural analgesia is a valuable and common technique for analgesia but involves risk to the spinal cord. There is significant pediatric experience safely placing thoracic epidurals via a caudal approach. The use of a stimulating catheter offers the advantage of real-time confirmation of appropriate catheter placement. We hypothesize that the tip of a stimulating epidural catheter can be reliably advanced to the thoracic epidural space with lumbar insertion in a porcine model.

METHODS

This prospective experimental porcine study evaluated the feasibility of placing the tip of a stimulating epidural catheter to a predefined thoracic epidural location after percutaneous lumbar epidural access in six live pigs. After the lumbar epidural space was accessed, a stimulating epidural catheter was advanced until the targeted thoracic myotome was stimulated. The final position of the catheter in relation to the targeted location was determined by fluoroscopy. All animals were euthanized at the end of the experiment, necropsy and spinal cord histology were then performed to assess the extent of spinal cord damage.

RESULTS

In all animals the epidural catheter tip could be accurately advanced to the targeted thoracic myotome. Gross subdural bleeding occurred in three of the six animals and deep spinal damage was observed in two of the six animals. In one animal, the catheter was placed in the subarachnoid space.

CONCLUSIONS

Accurate access to the thoracic epidural space is possible via a lumbar approach using a stimulating epidural catheter. Based on gross and histopathological examination, this technique resulted in frequent complications, including subdural hemorrhage, deep spinal cord damage, and subarachnoid catheter placement.

Caudal blocks

Caudal anesthesia is the single most important pediatric regional anesthetic technique. The technique is relatively easy to learn (1), has a remarkable safety record (2), and can be used for a large variety of procedures. The technique has been reviewed in the English (3) and French (4) literature, as well as in German guidelines (5) and in pediatric anesthesia textbooks (6).

Advancement of epidural catheter from lumbar to thoracic space in children: Comparison between 18G and 23G catheters

BACKGROUNDS AND OBJECTIVES

Lumbar-to-thoracic advancement of epidural catheter is a safe alternative to direct thoracic placement in children. In this prospective randomized study, success rate of advancement of two different types and gauges of catheter from lumbar-to-thoracic space were studied.

MATERIALS AND METHODS

Forty ASA I and II children (up to 6 years) undergoing thoracic or upper-abdominal surgery were allocated to either Group I (18G catheter) or Group II (23G catheter). After induction of general anesthesia a pre-determined length of catheter was inserted. Successful catheter placement was defined as the catheter tip within two segment of surgical incision in radio-contrast study. Intra-operative analgesia was provided by epidural bupivacaine and intravenous morphine. Post-operative analgesia was provided with epidural infusion of 0.1% bupivacaine+1mcg/ml fentanyl.

OBSERVATIONS AND RESULTS

Catheter advancement was successful in 3 cases in Group I and 2 cases in Group II. Five different types of catheter positions were found on X-ray. Negative correlation was found between age and catheter advancement [significance (2-tailed) =0.03]. However, satisfactory post-operative analgesia was obtained in 35 cases. Positive correlation was found between infusion rate, the number of segment of gap between desired level and the level reached [significance (2-tailed) =0.00]. 23G catheter use was associated with more technical complications.

CONCLUSION

Advancement of epidural catheter from lumbar to thoracic level was successful in only 10-15% cases but satisfactory analgesia could be provided by increasing the infusion rates.

Pro con debate: the use of regional vs systemic analgesia for neonatal surgery

In recent years the inclusion of regional techniques to pediatric anesthesia has transformed practice. Simple procedures such as caudal anesthesia with local anaesthetics can reduce the amounts of general anesthesia required and provide complete analgesia in the postoperative period while avoiding large amounts of opioid analgesia with potential side effects that can impair recovery. However, the application of central blocks (epidural and spinal local anesthesia) via catheters in the younger infant, neonate and even preterm neonate remains more controversial. The potential for such invasive maneuvers themselves to augment risk, can be argued to outweigh the benefits, others would argue that epidural analgesia can reduce the need for postoperative ventilation and that this not only facilitates surgery when intensive care facilities are limited, but also reduces cost in terms of PICU stay and recovery profile. Currently, opinions are divided and strongly held with some major units adopting this approach widely and others maintaining a more conservative stance to anesthesia for major neonatal surgery. In this pro-con debate the evidence base is examined, supplemented with expert opinion to try to provide a balanced overall view.

Accuracy of the epidural catheter position during the lumbar approach in infants and children: a comparison among L2-3, L3-4, and L4-5 approaches

Background

The aim of this study was to compare the accuracy of the position of the epidural catheter inserted from three different lumbar intervertebral spaces, L2-3, L3-4, and L4-5, in infants and children.

Methods

Seventy-five children were randomly allocated to 3 groups according to the epidural catheter insertion site (L2-3, L3-4, and L4-5). The epidural catheter tip was identified using 50% diluted Iohexol and fluoroscopy. The incidence of correct position was compared among the groups and between infants and children.

Results

The incidence of correct position was significantly higher in the L2-3 group as compared to the L3-4 and L4-5 groups (P = 0.023 and P = 0.046 respectively). The incidence of correct position was higher in infants compared to children (P = 0.017).

Conclusions

The L2-3 intervertebral space is preferable during epidural catheter insertion in children older than 1 year, but a low lumbar level should be considered in infants because they have a higher risk of neural damage.

Continuous lumbar/thoracic epidural analgesia in low-weight paediatric surgical patients: practical aspects and pitfalls

PURPOSE

Continuous epidural anaesthesia attenuates perioperative stress and avoids the need for systemic opioids. In addition, it may prevent the need for postoperative mechanical ventilation. The aim of the study was to prospectively follow the perioperative course of young infants treated with continuous thoracic/lumbar epidural anaesthesia for major surgery.

METHODS

Data were collected prospectively from 44 epidural anaesthetics in 40 infants (18 premature or former premature) weighing 1,400-4,300 g who underwent major abdominal surgery (33 cases), thoracic surgery (5), or both (1), or ano-rectal surgery (5) at our centre.

RESULTS

Epidural placement was achieved easily in all cases, with high quality analgesia for 24-96 h. Tracheal extubation was delayed after 4 anaesthetics due to muscle relaxant overdose (n = 1), surgeon's request (n = 2), and systemic opioid administration before epidural anaesthesia was considered (n = 1). Intraoperative complications included haemodynamic instability (n = 1) and vascular catheter placement (n = 5). Postoperative complications included meningitis (n = 1), insertion site erythema (n = 7), apnoea (n = 6; 4 premature and 2 full-term infants) and tracheal re-intubation (n = 6).

CONCLUSIONS

Continuous epidural analgesia is effective in low-weight infants undergoing major surgery. The trachea may be extubated immediately after surgery. Attention should be paid to the unique anatomical, physiological, and pharmacological aspects. The patients should be monitored carefully for pain, respiratory failure, and meningitis (an extremely rare complication).

Combined spinal-epidural anesthesia in major abdominal surgery in high-risk neonates and infants

BACKGROUND

Combined spinal-epidural anesthesia (CSE-A) is reportedly safe and effective for the pediatric population in infraumbilical surgery. Our main purpose was to describe our experience of this technique in neonates and infants undergoing elective major upper abdominal surgery.

METHODS

Spinal anesthesia was performed in 28 neonates and infants with isobaric bupivacaine 0.5%, 1 mg.kg(-1) followed by placement of a caudal epidural catheter to thoracic spinal segments. The catheter tip position was confirmed radiographically. Respiratory and hemodynamic data were collected before and after the CSE-A and throughout the operation, as a measure of anesthetic effectiveness. Complications related to the anesthesia technique were collected as a measure of the anesthetic technique safety.

RESULTS

Satisfactory surgical anesthesia was achieved in 24 neonates and infants, four patients were converted to general anesthesia. Respiratory and hemodynamic variables did not change significantly during surgery, compared with baseline values: oxygen saturation (P = 0.07), systolic and diastolic blood pressures (P = 0.143, P = 0.198 respectively), heart rate (P = 0.080) and respiratory rate (P = 0.127). However, twenty infants were fussy during the surgical procedures and were calmed with intravenous midazolam; our patients required oxygen supplementation and transient manual ventilation intraoperatively.

CONCLUSIONS

Combined spinal-epidural anesthesia could be considered as an effective anesthetic technique for elective major upper abdominal surgery in awake or sedated neonates and infants, and could be used cautiously by a pediatric anesthesiologist as an alternate to general anesthesia in high-risk neonates and infants undergoing upper gastrointestinal surgery.

New insights into regional anesthesia in children: new techniques and new indications

The applications and indications for pediatric regional anesthesia continue to increase. Several recent advances have occurred in the understanding of this technology in children, including improved techniques, alternative drug combinations, as well as prospective investigations to understand the nature and incidence of adverse effects associated with these techniques when used in pediatric patients. The following article will review recent information from the literature concerning various regional anesthetic techniques in children, including caudal epidural block, lumbar and thoracic epidural anesthesia, and peripheral nerve blockade.

Cervical epidural analgesia via a thoracic approach using nerve-stimulation guidance in adult patients undergoing total shoulder replacement surgery

BACKGROUND

Continuous cervical epidural anesthesia can provide excellent peri- and post-operative analgesia, although several factors prevent its widespread use. Advancing catheters from thoracic levels to the cervical region may circumvent these barriers, provided they are accurately positioned. We hypothesize that guiding catheters from thoracic to cervical regions using low-current epidural stimulation will have a high success rate and enable excellent analgesia in adults undergoing total shoulder arthroplasty.

METHODS

After Institutional Review Board approval, adult patients were studied consecutively. A 17-G Tuohy needle was inserted into the thoracic epidural space using a right paramedian approach with loss of resistance. A 20-G styletted epidural catheter, with an attached nerve stimulator, was primed with saline and a 1-10 mA current was applied as it advanced in a cephalad direction towards the cervical spine. Muscle twitch responses were observed and post-operative X-ray confirmed final placement. After a test dose, an infusion (2-8 ml/h) of ropivacaine 2 mg/ml and morphine 0.05 mg/ml (or equivalent) was initiated. Verbal analog pain scale scores were collected over 72 h.

RESULTS

Cervical epidural anesthesia was performed on 10 patients. Average current required to elicit a motor response was 4.8 +/- 2.0mA. Post-operative X-ray of catheter positions confirmed all catheter tips reached the desired region (C4-7). The technical success rate for catheter placement was 100% and excellent pain control was achieved. Catheters were positioned two to the left, four to the right and four to the midline.

CONCLUSION

This epidural technique provided highly effective post-operative analgesia in a patient group that traditionally experiences severe post-operative pain and can benefit from early mobilization.

Innovative approaches to neuraxial blockade in children: the introduction of epidural nerve root stimulation and ultrasound guidance for epidural catheter placement

Continuous epidural blockade remains the cornerstone of pediatric regional anesthesia. However, the risk of catastrophic trauma to the spinal cord when inserting direct thoracic and high lumbar epidural needles in anesthetized or heavily sedated pediatric patients is a concern. To reduce this risk, research has focused on low lumbar or caudal blocks (ie, avoiding the spinal cord) and threading catheters from distal puncture sites in a cephalad direction. However, with conventional epidural techniques, including loss-of-resistance for localization of the needle, optimal catheter tip placement is difficult to assess because considerable distances are required during threading. Novel approaches include electrical epidural stimulation for physiological confirmation and segmental localization of epidural catheters, and ultrasound guidance for assessing related neuroanatomy and real-time observation of the needle puncture and, potentially, catheter advancement. The present article provides a brief and focused review of these two advances, and outlines recent clinical experiences relevant to pediatric epidural anesthesia.

Epidural catheter placement in children: comparing a novel approach using ultrasound guidance and a standard loss-of-resistance technique

BACKGROUND

We report a prospective, randomized study to evaluate ultrasound guidance for epidural catheter placement in children 0-6 yr of age.

METHODS

Epidural catheters were placed at lumbar or thoracic cord levels in 64 children undergoing major surgery, using either ultrasonography or loss-of-resistance (LOR) for guidance. Using a 5-10 MHz linear ultrasound probe, the neuraxial structures were identified, the skin-epidural depth and epidural space was measured, the advancing epidural catheter visualized, and the spread of local anaesthetic verifying catheter position was confirmed. Epidural placement procedures were analysed for bone contacts and speed of execution. Children under 6 months were analysed separately.

RESULTS

Epidural placement involved bone contacts in 17% of children in the ultrasound group and 71% of children in the LOR group (P<0.0001). Epidurals were executed more swiftly in the ultrasound group [162 (75) s vs 234 (138) s; P<0.01]. Children under 6 months revealed a 0.9 correlation between skin-epidural depth and body weight.

CONCLUSIONS

Ultrasonography is a useful aid to verify epidural placement of local anaesthetic agents and epidural catheters in children. Advantages include a reduction in bone contacts, faster epidural placement, direct visualization of neuraxial structures and the spread of local anaesthetic inside the epidural space. Ultrasound guidance requires additional training and good manual skills, and should only be used once experience in ultrasound-guided techniques of regional anaesthesia has been acquired.

Thoracic epidural catheters via the caudal and lumbar approaches using styletted multiple port catheters in pediatric patients: a report of three cases

Advancing catheters from the lumbar and caudal epidural spaces to the thoracic level has been reported to be an alternative to the direct thoracic approach. However, as children grow, the threading of catheters in the epidural space becomes increasingly difficult. This report describes three cases of thoracic epidural placement using a multiport catheter threaded from the caudal and lumbar spaces using electrical stimulation guidance. In the first case, a multiport catheter was threaded 22 cm from the lumbar space to T8 following a failed attempt with a single-port catheter in a 9-year-old boy scheduled to undergo a right nephrectomy. In the second case, a multiport catheter was threaded 26 cm from the caudal space to T9 in a 3-year-old girl undergoing fundoplication. In the last case, a multiport catheter was inserted at the completion of a fundoplication in a 2-year-old girl after it had been confirmed that the single-port catheter inserted prior to surgery had not advanced to the desired thoracic level. The multiport catheter was threaded 17 cm without resistance from the caudal space to T9. In all cases, electrical stimulation was used to confirm the location of the catheter tip at the time of insertion. The position of the catheters was later confirmed by X-ray. The multiport catheter incorporates a stylet, which extends to a closed distal tip, within a catheter body that ejects fluid from three lateral holes in a direction perpendicular to the advancing catheter. These properties may facilitate the reliable advancement of catheters in the epidural space.

Paediatric caudal extradural catheterisation: an evaluation of a purpose designed equipment set

Using a purpose designed set of equipment, the Caudal Extradural Catheter Tray, Oxford Set (B Braun Medical Ltd, Sheffield, UK) we have evaluated the ease of cannulation of the caudal space, and the subsequent success in threading extradural catheters and obtaining satisfactory analgesia via the caudal route. The set was evaluated in 91 children (age range: 1 day to 10 years). Cannulation of the caudal space was achieved in all patients, and catheterisation of the extradural space was successful in 96.7% of patients. Postoperative analgesia was satisfactory in 95% of children who had continuous extradural analgesia. There were no major complications or neurological sequelae associated with using the set. We found the Caudal Extradural Catheter Tray provides the necessary equipment to perform extradural anaesthesia and analgesia safely and successfully in children of a wide age range.

Thoracic epidural analgesia via the lumbar approach using nerve stimulation in a pediatric patient with Down syndrome

This case illustrates the threading of an epidural catheter with electrical stimulation guidance from the lumbar epidural space to the thoracic space in a pediatric patient. A 17-year-old boy with Down syndrome, weighing 48 kg, was scheduled to undergo a laparotomy for duodenal obstruction and gastrostomy tube insertion. Combined general and continuous epidural anesthesia was selected for his anesthetic. Following the induction of general anesthesia and tracheal intubation, a 17G Tuohy needle (Arrow International, Inc., Reading, PA) was inserted into the lumbar space (L3-4) using loss of resistance with air. A 20G styletted epidural catheter was then inserted and threaded cranially. As the catheter was advanced, a low electrical current (1-10mA) was applied to the catheter. Motor response was observed from the lower limb muscles to the upper abdominal muscles as the catheter advanced cranially. After 22 cm of the epidural catheter had been inserted, intercostal muscle movement (T9 - 10) was observed at 3.0 mA. Radiographical imaging later confirmed the catheter tip at T10. The patient awoke without distress and was discharged to the ward with subsequent good pain control from a continuous epidural infusion of bupivacaine 0.1% with 1 microg ml(-1) fentanyl at 4-6 ml(-1).

Inadvertent Extra-Epidural Catheter Placement in an Infant

We report the inadvertent passage of an epidural catheter threaded from the caudal space out of a lumbar intervertebral foramen and into the lower thoracic paravertebral space in an infant. We identified the errant catheter by radiography and removed it without sequelae.

Inadvertent cervical epidural catheter placement via the caudal route using electrical stimulation

Inadvertent placement of an epidural catheter in the cervical region via the caudal route is described in an infant who underwent revision of a fundoplication. We attempted electrical stimulation (the Tsui test) via the epidural catheter to confirm correct placement and positioning of the catheter tip. In this case, the epidural catheter was inadvertently advanced to the cervical region, resulting in stimulation of the phrenic nerve. These diaphragmatic twitches were misinterpreted as chest wall twitches, and it was incorrectly assumed that the catheter was in the thoracic region. To avoid misinterpretation of the stimulation level, the catheter should be continuously stimulated while it is advanced. We also recommend that the catheter length be estimated before insertion (although doing so did not help in this case) and that the catheter position be radiographically confirmed after surgery.

Neuraxial blocks for anaesthesia and analgesia in children

PURPOSE OF REVIEW

The use of regional techniques in paediatric anaesthesia has increased dramatically. Our aim is to produce a comprehensive review of the recent literature on neuraxial blockade in infants and children, focusing on three topics: choice of local anaesthetic and adjunct drugs, technical aspects and complications.

RECENT FINDINGS

The current literature shows a trend towards using the single isomers (levobupivacaine or ropivacaine) rather than racemic bupivacaine. In addition, opioids as adjuncts are being challenged by clonidine and ketamine, which have more benign side effects. The spread of radiopaque dye within the epidural space (which may mimic that of local anaesthetic solutions) appears to be highly variable, although distribution is related to the volume injected. Recent techniques (e.g. ultrasound or stimulating catheters) have been developed to accurately identify the position of epidural catheters. In contrast to adults, neuraxial blockade using local anaesthetic solutions is associated with stable cardiovascular variables, even in children with congenital heart disease. Although the incidence of complications associated with paediatric neuraxial blockade is low, the potential risks must always be considered.

SUMMARY

It is likely that the use of epidural ketamine or clonidine as adjuncts to local anaesthetics will grow. Alternatives, such as midazolam, may offer advantages in particular circumstances, although rigorous evaluation of the safety of these solutions when injected along the neuraxis and the development of formulations without preservatives are needed. The use of stimulating caudal catheters or ultrasound-guided techniques appears to offer promising options for the future to more accurately position catheters.

Confirmation of Direct Epidural Catheter Placement Using Nerve Stimulation in Pediatric Anesthesia

We evaluated the success rate of using low current electrical stimulation (the Tsui test) to identify and confirm direct epidural catheter placement in a pediatric population. Thirty subjects received a standard anesthetic and administration of the Tsui test on epidural placement. The distribution of myotomal activity was recorded. The intended and actual level of the epidural catheter was compared. Myotomal activity was seen in all patients but one. The median current resulting in myotomal activity was 5.3 mA. The median difference between the intended and actual level as confirmed on radiograph was 1.8 levels. The clinical success rate was 93.9%. The positive predictive value of the Tsui test was 82%; i.e., in 23 of 28 cases, the Tsui test correctly identified the position of the epidural catheter tip within 2 vertebral levels. The test did not offer any added advantage when used in the setting of directly placed epidural catheters in our institution over "blind" methods already used to confirm catheter position when using cutaneous landmarks and test dosing.

IMPLICATIONS

A new technique to confirm epidural catheter position uses low current electrical stimulation in pediatric patients. This study evaluated the use of electrical stimulation in 30 pediatric patients for directly placed catheters. Electrical stimulation did not provide any advantage over conventional methods (e.g., cutaneous landmarks) for confirmation of catheter position.

Detection of epidural catheters with ultrasound in children

BACKGROUND

The aim of this study was to assess whether a noninvasive imaging technique such as ultrasound could visualize an epidural catheter in the epidural space in children.

METHODS

Following local ethics committee approval and informed parental consent a pilot study of 12 cases was performed. Children undergoing major surgery requiring epidural analgesia were recruited. All catheters were introduced via the lumbar region. All children were scanned within 24 h of epidural insertion by consultant paediatric radiologists. If the catheter was identified in the epidural space then an attempt was made to visualize the entire length of the catheter.

RESULTS

The epidural catheter was detected in nine of 12 patients. All of these were less than 6 months old. The entire length of the catheter was visualized in five of the nine patients. It was possible to estimate the most cephalad level of the catheter in seven of the nine patients. This was in the thoracic region in all cases and an appropriate level for the intended surgical procedure. It was not possible to precisely identify the tip of the catheter as a distinct entity using ultrasound.

CONCLUSION

This study shows that it is possible to visualize an epidural catheter in the epidural space in children under 6 months of age using ultrasound.

Patient-controlled epidural analgesia in children: can they do it?

Extensive clinical experience and many studies support the use of i.v. patient-controlled analgesia (i.v. PCA) and regional anesthesia techniques for the treatment of postoperative pain in children. In contrast, little has been reported about the ability of children to use patient-controlled epidural analgesia (PCEA) or about the efficacy of this technique. We report a descriptive analysis of prospectively recorded data in 128 children (132 procedures) in whom PCEA was used for acute postoperative pain control. Satisfactory analgesia was obtained in 119 patients (90.1%) for up to 103 h with no episodes of desaturation and without clinical evidence of toxicity or serious adverse effects. Analgesia was satisfactory with the initial settings in 89 patients; in 38 others, this was achieved with changes in PCEA settings or solution. Five patients were switched to i.v. PCA because of inadequate analgesia. Eight patients with satisfactory analgesia were converted to i.v. PCA because of adverse effects. Children as young as 5 yr had the cognitive ability to understand and the willingness to use PCEA, consistent with reported use of i.v. PCA. Careful attention should be paid to the total hourly local anesthetic dose to avoid exceeding the recommended limits. Our prospectively collected data demonstrate that PCEA provides satisfactory analgesia with a small incidence of adverse side effects in children and should be considered along with other strategies in pediatric postoperative pain management.

IMPLICATIONS

A descriptive analysis of prospectively recorded data in 132 children receiving patient-controlled epidural analgesia for postoperative pain relief demonstrates satisfactory analgesia without serious toxicity or side effects in children as young as 5 yr. This modality should be considered as another strategy in pediatric postoperative pain management.

Complications of neuraxial blockade

Epidural and spinal anesthesia enjoy wide usage in modern practice, and each can provide reliable and safe anesthesia. Although the techniques appear to the casual observer to require relatively straightforward technical skill, both are fraught with myriad hazards and potential complications. It is the familiarity with and the understanding of these complications that makes for safe and professional practice of these techniques.

Thoracic epidural catheter placement via the caudal approach in infants by using electrocardiographic guidance

We examined the success of inserting epidural catheters via the caudal route in infants by using electrocardiographic guidance. A case series of 20 patients with thoracic epidural analgesia was studied. After the induction of general anesthesia, an 18-gauge IV catheter was inserted into the caudal space to allow threading of a 20-gauge epidural catheter. The electrocardiogram (ECG) tracings via the epidural catheter, as well as the surface ECG at the target spine level, were recorded simultaneously with a modified two-channel five-lead ECG system. The epidural catheter was advanced from the caudal space until the tip reached the target level as demonstrated by a match in the configuration of the epidural ECG tracing to that of the surface ECG tracing at the target level. The catheter tip location was verified by postoperative radiographs. All catheter tips were located within two vertebrae of the target level, and satisfactory intraoperative epidural anesthesia was achieved in all subjects.

IMPLICATIONS

Epidural electrocardiography may be used to guide the positioning of the thoracic epidural catheter tip via the caudal approach to the appropriate dermatome for optimum analgesia.

The caudal catheter in neonates: where are the restrictions?

PURPOSE OF REVIEW

In neonates, epidural catheters inserted at the sacral hiatus can easily be advanced to a lumbar or thoracic level. These 'caudal catheters' are popular because they allow the neonate to benefit from epidural analgesia without the concerns of spinal cord injury potentially associated with primary thoracic placement in an asleep neonate. This review looks at use and benefits, and risks and complications of caudal epidural catheters in neonates.

RECENT FINDINGS

Restrictions of neonatal caudal catheters are related to risks associated with placement and advancement of the catheters, infectious risks of caudal catheters, and toxicity risks related to the higher free fraction and lower clearance of bupivacaine in neonates. Caudal catheters in neonates are popular, but evidence that they improve outcome is lacking.

SUMMARY

Epidural anesthesia and analgesia for neonates should be performed and managed by pediatric anesthesiologists. Potential risks and complications must be appreciated and all steps to maximize safety of the technique must be taken. In particular, close postoperative observation and pain service management are indispensable. Future research should investigate the risks of caudal and segmentally placed catheters in neonates, study the role of epidural analgesia in outcome improvement for neonates, and guide us to safer use of local anesthetics suitable for neonates with their pharmacologic immaturity.

Practical pediatric regional anesthesia

In children, regional anesthetic techniques are safe and effective adjuncts to general anesthesia and for postoperative pain relief. Application of the techniques described in this article will contribute to improved care for pediatric patients undergoing surgical procedures. The judicious choice of local anesthetics, along with the blockades of targeted nerves, decrease the need for supplemental analgesics in the recovery phase.

Thoracic epidural analgesia via the caudal approach in pediatric patients undergoing fundoplication using nerve stimulation guidance

IMPLICATIONS

Epidural catheter placement using electrical stimulation guidance is an alternative approach for positioning the catheter into the thoracic region via the caudal space. This easily performed clinical assessment provides optimization of catheter tip positioning for achieving effective pain control.

Regional anesthesia in pediatrics

The use of regional anesthetic techniques in infants and children has become increasingly accepted as standard care. The most commonly performed regional anesthetic techniques used in pediatric patients are the caudal and lumbar approaches to the epidural space, ilioinguinal/iliohypogastric, and penile nerve blockade. These and other techniques are reviewed, along with specific issues such as risks, benefits, drug dosage, and local anesthetic toxicity. The safety of regional anesthetic techniques in pediatric patients is addressed, with recommendations for prevention and treatment of complications.

Thoracic epidural analgesia via the caudal approach using nerve stimulation in an infant with CATCH22

PURPOSE

To illustrate insertion of an epidural catheter via caudal route in a small infant under electrical stimulation guidance.

CLINICAL FEATURES

A six month old boy, weighting 4.25 kg, with a diagnosis of CATCH22 (Cardiac abnormality/abnormal faces, T cell deficit due to thymic hypoplasia, cleft palate, hypocalcemia due to hypoparathyroidism resulting from 22q11 deletion) was scheduled for fundoplication and gastrostomy tube (G-tube) insertion. A combined light general anesthesia and continuous epidural anesthesia technique was selected. Following induction of general anesthesia and tracheal intubation with 1.5 mg midazolam, 10 microg fentanyl and 10 mg succinylcholine, a 16G intravenous catheter was inserted into the caudal space. A 19G epidural catheter (Arrow Flextip Plus) epidural catheter was then inserted up cranially. A low electrical current (1-10mA) was then applied through the catheter. The level of motor movement was advanced from the lower limb muscles to the upper abdominal muscles as the catheter was threaded cranially. After 19 cm of epidural catheter had been inserted, intercostal muscle movement (T9-10 level) was observed at 4.2mA. The tip of the catheter was later confirmed to be at the T9-10 interspace by radiographical imaging. The patient awakened without distress and the trachea was extubated the same evening. The infant was discharged to the ward next morning with good pain relief from a continuous epidural infusion of bupivacane 0.1% with 1 microg x ml(-1) at 1.6 ml(-1).

CONCLUSION

Epidural stimulation may help placement of the epidural catheter at the appropriate dermatome for effective anesthesia and analgesia.

Accidental pleural puncture by a thoracic epidural catheter

We report the occurrence of an accidental pleural puncture by an epidural catheter that happened during the attempted induction of thoracic epidural anaesthesia using a paramedian approach in an awake patient. The incorrect placement of the catheter was recognised while the patient was undergoing thoracoscopic surgery. The possibility of accidental pleural puncture during attempted thoracic epidural catheter placement by either the paramedian or the midline approach should be borne in mind. A misplaced catheter may injure lung tissue and result in a potentially dangerous intra-operative tension pneumothorax.