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

Caudal epidural blocks in paediatric patients: a review and practical considerations

Caudal epidural blockade in children is one of the most widely administered techniques of regional anaesthesia. Recent clinical studies have answered major pharmacodynamic and pharmacokinetic questions, thus providing the scientific background for safe and effective blocks in daily clinical practice and demonstrating that patient selection can be expanded to range from extreme preterm births up to 50 kg of body weight. This narrative review discusses the main findings in the current literature with regard to patient selection (sub-umbilical vs mid-abdominal indications, contraindications, low-risk patients with spinal anomalies); anatomical considerations (access problems, age and body positioning, palpation for needle insertion); technical considerations (verification of needle position by ultrasound vs landmarks vs 'whoosh' or 'swoosh' testing); training and equipment requirements (learning curve, needle types, risk of tissue spreading); complications and safety (paediatric regional anaesthesia, caudal blocks); local anaesthetics (bupivacaine vs ropivacaine, risk of toxicity in children, management of toxic events); adjuvant drugs (clonidine, dexmedetomidine, opioids, ketamine); volume dosing (dermatomal reach, cranial rebound); caudally accessed lumbar or thoracic anaesthesia (contamination risk, verifying catheter placement); and postoperative pain. Caudal blocks are an efficient way to offer perioperative analgesia for painful sub-umbilical interventions. Performed on sedated children, they enable not only early ambulation, but also periprocedural haemodynamic stability and spontaneous breathing in patient groups at maximum risk of a difficult airway. These are important advantages over general anaesthesia, notably in preterm babies and in children with cardiopulmonary co-morbidities. Compared with other techniques of regional anaesthesia, a case for caudal blocks can still be made.

Recent trends in paediatric regional anaesthesia

Paediatric regional anaesthesia today is one of the fastest growing and exciting aspects of paediatric anaesthesia, which requires an ongoing fervour to learn. Application of paediatric regional anaesthesia in neonates, infants, toddlers and children is undertaken to treat perioperative pain without disturbing the physiological milieu with additional advantages elaborated in the review. The available choices, traditional methods and the most recently described methods are discussed with emphasis on their advantages and disadvantages. Clear pointers for selection of the blocks are also discussed. To present a holistic overview of this rapidly growing subject, a comprehensive literature search was performed in May 2019 in MEDLINE, PubMed and Google Scholar to retrieve articles pertaining to all the above topics. The keywords used in various combinations included 'Central neuraxial, blocks, Paediatric(s)', 'Peripheral Nerve blocks', 'Safety, controversies, regional, anaesthesia'.

Localization of epidural space: A review of available technologies

Although epidural analgesia is widely used for pain relief, it is associated with a significant failure rate. Loss of resistance technique, tactile feedback from the needle, and surface landmarks are traditionally used to guide the epidural needle tip into the epidural space (EDS). The aim of this narrative review is to critically appraise new and emerging technologies for identification of EDS and their potential role in the future. The PubMed, Cochrane Central Register of Controlled Clinical Studies, and Web of Science databases were searched using predecided search strategies, yielding 1048 results. After careful review of abstracts and full texts, 42 articles were selected to be included. Newer techniques for localization of EDS can be broadly classified into techniques that (1) guide the needle to the EDS, (2) identify needle entry into the EDS, and (3) confirm catheter location in EDS. An ideal method should be easy to learn and perform, easily reproducible with high sensitivity and specificity, identifies inadvertent intrathecal and intravascular catheter placements with ease, feasible in perioperative setting and have a cost-benefit advantage. Though none of them in their current stages of development qualify as an ideal method, many show tremendous potential. Some techniques are useful in patients with difficult spinal anatomy and infants, and thus are complementary to traditional methods. In addition to improving the existing technology, future research should aim at proving the superiority of these techniques over traditional methods, specifically regarding successful EDS localization, better safety profile, and a favorable cost-benefit ratio.

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.

Perioperative management of classic bladder exstrophy

The exstrophy-epispadias complex is a rare congenital malformation of the genitourinary system, abdominal wall muscles, and pelvic structures. Modern surgical repairs focus on reconstruction of the bladder and its adjacent structures, with the goal of achieving urinary continence, a satisfactory cosmetic result, and a high quality of life. Complex surgery in neonates and young children, as well as a prolonged postoperative course require close collaboration between surgeons, anesthesiologists, intensivists, pediatricians, and an experienced nursing staff. This article will review the spectrum of bladder exstrophy anomalies, the surgical repair, and the perioperative interdisciplinary management.

Recent developments in paediatric neuraxial blocks

Paediatric anaesthesia and paediatric regional anaesthesia are intertwined. Almost all surgeries unless contradicted could be and should be supplemented with a regional block. The main objective of this review is to elaborate on the recent advances of the central neuraxial blocks, such as application of ultrasound guidance and electrical stimulation in the pursuit of safety and an objective end point. This review also takes account of the traditional technique and understand the benefits as well the risk of each as compared with the recent technique. The recent trends in choosing the most appropriate peripheral block for a given surgery thereby sparing the central neuroaxis is considered. A penile block for circumcision or a sciatic block for unilateral foot surgery, rather than caudal epidural would have a better risk benefit equation. Readers will find a special mention on the recent thoughts on continuous epidural analgesia in paediatrics, especially its rise and fall, yet its unique importance. Lastly, the issue of block placements under sedation or general anaesthesia with its implication in this special population is dealt with. We conducted searches in MEDLINE (PubMed) and assessed the relevance of the abstracts of citations identified from literature searches. The search was carried out in English, for last 10 years, with the following key words: Recent advances in paediatric regional anaesthesia; ultrasound guidance for central neuraxial blocks in children; role of electrical stimulation in neuraxial blocks in children; complications in neuraxial block. Full-text articles of potentially relevant abstracts were retrieved for further review.

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.

Acute pain management in children

The greatest advance in pediatric pain medicine is the recognition that untreated pain is a significant cause of morbidity and even mortality after surgical trauma. Accurate assessment of pain in different age groups and the effective treatment of postoperative pain is constantly being refined; with newer drugs being used alone or in combination with other drugs continues to be explored. Several advances in developmental neurobiology and pharmacology, knowledge of new analgesics and newer applications of old analgesics in the last two decades have helped the pediatric anesthesiologist in managing pain in children more efficiently. The latter include administering opioids via the skin and nasal mucosa and their addition into the neuraxial local anesthetics. Systemic opioids, nonsteroidal anti-inflammatory agents and regional analgesics alone or combined with additives are currently used to provide effective postoperative analgesia. These modalities are best utilized when combined as a multimodal approach to treat acute pain in the perioperative setting. The development of receptor specific drugs that can produce pain relief without the untoward side effects of respiratory depression will hasten the recovery and discharge of children after surgery. This review focuses on the overview of acute pain management in children, with an emphasis on pharmacological and regional anesthesia in achieving this goal.

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.

Ultrasonographic guidance in pediatric regional anesthesia. Part 2: techniques

The benefits of regional anesthesia are well documented. The downsides of such techniques have been a significant failure rate and a potential for serious complications. Nearly, all regional blocks were first described as essentially 'blind' techniques. The development of high-resolution portable ultrasound (US) has made the use of US for regional anesthesia possible. Improved understanding of sonographic anatomy should lessen both the failure rate and the possibility of incurring serious complications. Natural caution has dictated that only a selection of blocks used in adults has been commonly used in pediatric practice, but with the aid of US, the repertoire of blocks for infants and children may be widened. The second part of this review will concentrate on the practice of both peripheral and central blocks.

Ultrasound assessment of caudal catheter position in infants

The positioning of caudally inserted epidural catheters is crucial to their effectiveness. However, level assessment can be difficult and time consuming. We report the use of ultrasound to assess the catheter position in three patients aged between 1 and 10 months. The advantages and disadvantages of this technique are discussed in relation to other methods of assessing caudal catheter placement.

Postoperative analgesia in infants and children

PURPOSE OF REVIEW

Although postoperative analgesia in infants and children should be an integral part of the perioperative management, undertreatment of pain is not rare in clinical practice and may influence outcome and long term behaviour. Therefore, this review summarizes results of recent papers and discusses actual trends and future perspectives concerning postoperative pharmacologic pain therapy in infants and children.

RECENT FINDINGS

A multimodal approach using locoregional anesthesia and systemic analgesics is a widely accepted technique. New developments include new local anesthetics with a wider margin of safety and more experience with adjuvants, catheter techniques and systemic analgesics. Replacement of bupivacaine with ropivacaine may be prudent especially for prolonged epidural infusion, use in neonates, impaired hepatic metabolic function, and anesthetic techniques requiring large dosage of local anesthetic. The limited duration of analgesia after single blocks can be prolonged by use of adjuvants (clonidine, ketamine), catheter techniques or early use of systemic analgesics. Non-opioids (acetaminophen, non-steroidal anti-inflammatory drugs) are appropriate for patients with mild to moderate pain or as a component of multimodal pain therapy. Patient- and nurse-controlled analgesia are convenient ways for opioid administration in infants and children.

SUMMARY

The reviewed studies suggest that there are many reliable agents and techniques available to provide a safe and effective postoperative analgesia even in neonates and small infants.