Paediatric regional anaesthesia : a clinical anatomical study

In 1973, Winnie and co-workers stated that no technique could truly be called simple, safe and consistent until the anatomy has been closely examined. This is evident when looking at the literature where many anatomically based studies regarding regional techniques in adults have resulted in the improvement of known techniques, as well as the creation of safer and more efficient methods. Anaesthesiologists performing these procedures should have a clear understanding of the anatomy, the influence of age and size, and the potential complications and hazards of each procedure to achieve good results and avoid morbidity. A thorough knowledge of the anatomy of paediatric patients is also essential for successful nerve blocks, which cannot be substituted by probing the patient with a needle attached to a nerve stimulator. The anatomy described in adults is also not always applicable to children, as anatomical landmarks in children vary with growth. Bony landmarks are poorly developed in infants prior to weight bearing, and muscular and tendinous landmarks, commonly used in adults, tend to lack definition in young children. The aim of this research was therefore to study a sample of neonatal cadavers, as well as magnetic resonance images in order to describe the relevant anatomy associated with essential regional nerve blocks, commonly performed by anaesthesiologists in South African hospitals. This research has brought to light the differences between neonatal and adult anatomy, which is relevant since the majority of paediatric regional anaesthetic techniques were developed from studies originally conducted on adult patients. Current techniques were also analysed and where necessary new improvements, using easily identifiable and constant bony landmarks, are described for the safe and successful performance of these regional nerve blocks in paediatric patients. In conclusion a sound knowledge and understanding of anatomy is important for the success of any nerve blocks. This study showed that extrapolation of anatomical findings from adult studies and simply downscaling these findings in order to apply them to infants and children is inappropriate and could lead to failed blocks or severe complications. It would therefore be more beneficial to use the data obtained from dissection of neonatal cadavers.Thesis (PhD)--University of Pretoria, 2010.Anatomyunrestricte

Paediatric regional anaesthetic procedures: clinical anatomy competence, pitfalls and complications

Clinical procedures are an important part of the daily work of doctors of various specialities, including the practice of regional anaesthetic procedures on paediatric patients. The competency that a doctor displays in clinical procedures is an important aspect of their overall clinical competence and the successful performance of regional blocks demands a working and yet specific knowledge of the anatomy underlying each procedure, especially knowledge regarding the relative depth or specific positions of certain key structures in paediatric patients, as it is known that the anatomy of children differ to a greater or lesser degree from that of adults. Precise information on epidemiology and morbidity of paediatric regional anaesthesia, especially from a clinical anatomy perspective, remains scarce. The aim of this study was therefore: (1) to determine, through means of a questionnaire, the scope of regional anaesthetic techniques performed on paediatric patients in South Africa, as well as, determine the competence of anaesthesiologists to perform these procedures based on their clinical anatomy knowledge regarding each nerve block; (2) select 5 problem procedures based on the anatomical competence that anaesthesiologists display when performing each nerve block; and (3) develop an extensive, referenced clinical anatomy knowledge base regarding each of the 5 problem procedures. A list of 18 regional anaesthetic procedures common in paediatric practice was compiled and a detailed questionnaire was completed by a randomly selected sample of anaesthesiologists (n=80) working in both government institutions and in private practice. The problem procedures chosen were those that were performed most often; ranked important; encountered most difficulties and complications; where anaesthesiologists felt uncomfortable performing the procedures and where the influence of clinical anatomy knowledge on the safe and successful performance of the procedure was ranked highest. The 5 problem procedures selected are the following: caudal epidural block, lumbar epidural block, the axillary approach to the brachial plexus, femoral nerve block and the ilioinguinal/ iliohypogastric nerve block. A referenced clinical anatomy knowledge base was developed by an extensive literature review of the selected procedures under the following headings: Indications, contraindications, step-by-step technique, anatomical pitfalls, anatomically related complications and references.Dissertation (MSc (Anatomy))--University of Pretoria, 2006.Anatomyunrestricte

Point de perfusion intra-osseux alternatif théorique chez les enfants gravement hypovolémiques

BACKGROUND : Studies have shown that the venous system tends to collapse during hypovolemic shock. The use of the bone marrow space for infusions is an effective alternative, with the tibial insertion site being the norm. OBJECTIVES : This study was conducted to determine a quick intraosseous infusion method that could be an alternative to the tibial route in neonates during emergency situations. METHOD : A sample of 30 neonatal cadavers was dissected to explore a possible alternative to the tibial insertion site. The needle was inserted in the superolateral aspect of the humerus. The needle infusion site was then dissected to determine possible muscular and neurovascular damage that might occur during the administration of this procedure, with the greatest concern being the posterior circumflex humeral artery and axillary nerve exiting the quadrangular space. The distance of the needle insertion site was measured in relation to the soft tissue as well as to bony landmarks. RESULTS : The calculated 95% confidence interval shows that the needle can be safely inserted into the intraosseous tissue at the greater tubercle of the humerus 9.5 mm – 11.1 mm from the acromion. This is about a little finger’s width from the acromioclavicular joint. CONCLUSION : Anatomically, the described site is suggested to offer a safe alternative access point for emergency infusion in severely hypovolemic newborns and infants, without the risk of damage to any anatomical structures.CONTEXTE : Des études ont montré que le système veineux tendait à l’effondrement lors d’un choc hypovolémique. L’utilisation de l’espace de la moelle osseuse pour des perfusions est une alternative efficace, le point d’insertion tibial étant la norme. OBJECTIFS : Cette étude a été menée afin d’établir une méthode de perfusion intra-osseuse rapide qui pourrait être une alternative à la voie tibiale chez les nouveau-nés lors de situations d’urgence. METHODE : Un échantillon de 30 cadavres néonatals a été disséqué pour explorer une alternative possible au point d’insertion tibial. L’aiguille a été insérée dans la partie supéro-externe de l’humérus. Le point de perfusion de l’aiguille a ensuite été disséqué afin de déterminer d’éventuels dommages musculaires et neurovasculaires qui auraient pu se produire lors de l’administration de cette procédure, la plus grande préoccupation étant l’artère circonflexe humérale postérieure et le nerf axillaire sortant de l’espace quadrangulaire. La distance entre le point d’insertion de l’aiguille a été mesurée par rapport au tissu mou et à des repères osseux. RESULTATS : L’intervalle de confiance à 95% calculé montre que l’aiguille peut être insérée en toute sécurité dans le tissu intra-osseux au niveau du tubercule majeur de l’humérus à 9.5 mm – 11.1 mm de l’acromion. Ceci représente environ la largeur d’un petit doigt à partir de l’articulation acromio-claviculaire. CONCLUSION : Sur le plan anatomique, on suggère le point décrit afin d’offrir un point d’accès alternatif sûr pour la perfusion d’urgence chez les nouveau-nés et les nourrissons gravement hypovolémiques, sans risque de dommage aux structures anatomiques.http://www.phcfm.orgam201

External jugular vein pierced by supraclavicular branches in a neonatal cadaver : a case report

Anatomical variations in the venous structure and drainage patterns in the neck are not uncommon. However, this is the first known report on the external jugular vein being pierced by supraclavicular branches. In the lateral cervical region of a neonatal cadaver, the supraclavicular branches penetrated the external jugular vein superior to the clavicle, resulting in a circular venous channel formed around the nerve trunk. Variations such as these are important to note in order to minimize possible intra-operative complications sustained during surgical interventions such as venous catherization or nerve grafts.http://link.springer.com/journal/12565hj2022Anatom

Degenerative trends of the palmaris longus muscle in a South African population

The literature reports that the palmaris longus muscle (PL) is only found in mammals in which the forelimbs are weight-bearing extremities. It is suggested that the function of this muscle has been taken over by the other flexors in the forearm. Terms used in the literature to describe the diminishing of this muscle include retrogressive or phylogenetic degenerative trends. The aims of this study were to determine the prevalence of PL in a South African population and whether a phylogenetic degenerative trend for the PL exists. To determine the prevalence of the PL, five groups, representing different age intervals (Years 0–20, 21–40, 41–60, 61–80, and 81–99) were used. A sample of 706 participants of various ages was randomly selected. Statistical analysis included comparisons of the prevalence of the muscle between males and females and left and right sides, using a student t-test. A Chi-squared test was used to determine a possible phylogenetic degenerative trend of PL within the five groups. The sample yielded a bilateral absence of the PL in 11.9% of the cases. The muscle was unilaterally absent on the left side in 7.65% and 6.94% on the right side. The Chi-squared tests revealed a P-value of 0.27 for the left arm and 0.39 for the right arm. No obvious trend could be established for the phylogenetic degeneration of the PL in this study. It would appear that the PL muscle should not be considered as a phylogenetically degenerating muscle in a South African population.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1098-2353hb201

Descriptive study of the differences in the level of the conus medullaris in four different age groups

In performing neuraxial procedures, knowledge of the location of the conus medullaris in patients of all ages is important. The aim of this study was to determine the location of conus medullaris in a sample of newborn/infant cadavers and sagittal MRIs of children, adolescents and young adults. MATERIALS AND METHODS: The subjects of both the samples were subdivided into four developmental stages. No statistical difference was seen between the three older age groups (p>0.05). A significant difference was evident when the newborn/infant stage was compared with the other, older stages (p<0.001 for all comparisons). RESULTS: In the newborn/infant group the spinal cord terminated most frequently at the level of L2/L3 (16%). In the childhood stage, the spinal cord terminated at the levels of T12/L1 and the lower third of L1 (21%). In the adolescent population, it was most often found at the level of the middle third of L1 and L1/L2 (19%). Finally, in the young adult group, the spinal cord terminated at the level of L1/L2 (25%). This study confirmed the different level of spinal cord termination between newborns/infants less than one year old and subjects older than one year. In this sample the conus medullaris was not found caudal to the L3 vertebral body, which is more cranial than the prescribed level of needle insertion recommended for lumbar neuraxial procedures. CONCLUSION: It is recommended that the exact level of spinal cord termination should be determined prior to attempting lumbar neuraxial procedures in newborns or infants.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1098-23532016-07-31hb201

The value of Tuffier’s line for neonatal neuraxial procedures

The spine of L4 usually lies on a line drawn between the highest points of the iliac crests (Tuffier’s line) in adults. Although its accuracy has been questioned, it is still commonly used to identify the spinous process of the 4th lumbar vertebra before performing lumbar neuraxial procedures. In children, this line is said to cross the midline at the level of L5. A literature search revealed that the description this surface anatomical line is vague in neonates. The aims of this study were to determine the vertebral level of Tuffier’s line, as well as its distance from the apex of the sacrococcygeal membrane (ASM), in 39 neonatal cadavers in both a prone and flexed position. It was found that when flexed, Tuffier’s line shifted from the level of L4/L5 (prone position) to the upper third of L5. The mean distance from the ASM to Tuffier’s line was 23.64mm when prone and 25.47mm when flexed, constituting a statistically significant increase in the distance (p=0.0061). Therefore, in the absence of advanced imaging modalities, Tuffier’s line provides practitioners with a simple method of determining a level caudal to the termination of the spinal cord, at approximately the L4/L5 in a prone neonate and the upper margins of L5 when flexed.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1098-2353hb201

Proximal tibial dimensions in a formalin-fixed neonatal cadaver sample : an intraosseous infusion approach

DATA AVAILABILITY : The quantitative and qualitative data used to support the findings of this study are included within the article, and additional data may be requested from the corresponding author.PURPOSE : Methods to administer intramedullary medication and fluid infusion in both adults and children date to the early twentieth century. Studies have shown that intraosseous access in the proximal tibia is ideal for resuscitation efforts as fewer critical structures are at risk, and neither is the blood flow to the lower limbs compromised. Insertion of a needle in children younger than 5 years does have the risk to damage to the epiphyseal growth plate. Therefore, the aim of this study was to determine the ideal intraosseous insertion site distal to the epiphyseal growth plate in neonates. METHODS : The samples consisted of both the left and right sides of 15 formalin-fixed neonatal cadavers. The dimensions were measured on the superior surfaces of each section, anteromedial border, cortical thickness, and medullary space. RESULTS : The most desirable location to gain vascular access is at 10 mm inferior to the tibial tuberosity. CONCLUSION : The smallest cortical thickness (1.32 mm), the largest medullary space (4.50 mm), and the largest anteromedial surface (7.72 mm) were observed at 10 mm inferior to the tibial tuberosity. It is imperative that health care professionals are familiar with the osteological sites that could be safely used for an intraosseous infusion procedure.https://link.springer.com/journal/276hj2023AnatomySurger

The surgical anatomy of the axillary approach for nerve transfer procedures targeting the axillary nerve

Purpose: The exact relational anatomy for the anterior axillary approach, targeting the axillary nerve for nerve transfers/grafts, has not been fully investigated. Therefore, this study aimed to dissect and document the gross anatomy surrounding this approach, specifically regarding the axillary nerve and its branches. Methods: Fifty-one formalin-fixed cadavers (98 axilla) were bilaterally dissected simulating the axillary approach. Measurements were taken to quantify distances between identifiable anatomical landmarks and relevant neurovascular structures encountered during this approach. The musculo-arterial triangle, described by Bertelli et al., to aid in identification on localization of the axillary nerve, was also assessed. Results: From the origin of the axillary nerve till (1) latissimus dorsi was 62.3 ± 10.7 mm and till (2) its division into anterior and posterior branches was 38.8 ± 9.6 mm. The origin of the teres minor branch along the posterior division of the axillary nerve was recorded as 6.4 ± 2.9 mm in females and 7.4 ± 2.8 mm in males. The musculo-arterial triangle reliably identified the axillary nerve in only 60.2% of the sample. Conclusion: The results clearly demonstrate that the axillary nerve and its divisions can be easily identified with this approach. The proximal axillary nerve, however, was situated deep and therefore challenging to expose. The musculo-arterial triangle was relatively successful in localising the axillary nerve, however, more consistent landmarks such as the latissimus dorsi, subscapularis, and quadrangular space have been suggested. The axillary approach may serve as a reliable and safe method to reach the axillary nerve and its divisions, allowing for adequate exposure when considering a nerve transfer or graft

Revisiting the anatomy of the ilio-inguinal/iliohypogastric nerve block

BACKGROUND : The ilio-inguinal/iliohypogastric nerve block (INB) is one of the most common peripheral nerve block techniques in pediatric anesthesia, which is largely due to the introduction of ultrasound (US) guidance. Despite the benefits of US guidance, the absence of an US machine should not deter the provider from performing INB, considering that many institutions, especially in developing countries, cannot afford to provide ultrasound machines in their anesthesiology departments. The aim of this study was to revisit the anatomical position of the ilio-inguinal and iliohypogastric nerves in relation to the anterior superior iliac spine (ASIS), in a large sample of neonatal cadavers, and compare the results with a similar group in a previously published US-guided study. METHODS : With Ethics Committee approval, the ilio-inguinal and iliohypogastric nerves were carefully dissected in 54 neonatal cadavers. RESULTS : In the total sample, the ilio-inguinal nerve was found to be 2.2 1.2 mm from the ASIS, on a line connecting the ASIS to the umbilicus. The iliohypogastric nerve was on average 3.8 1.3 mm from the ASIS. For the entire sample, the optimal needle insertion site was 3.00 mm from the ASIS. Although there is a strong correlation between the needle insertion point and the weight of the neonate, this will only ‘fit’ for 60%of the population. CONCLUSION : The linear regression formula; needle insertion distance (mm) = 0.6 9 weight + 1.8 can be used as a guideline for the position of the ilio-inguinal and iliohypogastric nerves.http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1460-9592hb201