Spinal anesthesia is a remarkable use of local anesthesia and involves the injection of an anesthetic agent in the lumbar spine. This agent is injected into the cerebrospinal fluid so that the nerves in that region are anesthetized, preventing sensation in the spinal cord levels affected by those nerves (DeLeon & Wong, 2023). The significance of this approach lies not only in its efficacy but also in its potential to reduce reliance on general anesthesia, minimizing risks and complications of general anesthesia. Anesthesiologists must, however, be aware of the differences between spinal anesthesia in adults and in pediatrics.
Generally, spinal anesthesia is performed low in the lumbar spine to avoid damage to the spinal cord (DeLeon & Wong, 2023). Meticulous positioning is needed to ensure that sensory, motor, and autonomic nerves are effectively blocked (DeLeon & Wong, 2023). Spinal anesthesia can be used for any procedures involving the lower extremities, abdomen, pelvis, or perineum.
Spinal anesthesia was first used on a pediatric patient in 1889. However, despite its potential, it did not gain immediate widespread acceptance. This was partly due to the concurrent advancements in general anesthesia techniques (Feehan & Packiasabapathy, 2023). Furthermore, pediatrics cannot just be regarded as smaller adults for the purposes of spinal anesthesia. Children have unique anatomic and physiological differences which must be considered in cases of spinal anesthesia. For example, children have a heightened requirement for local anesthetics and have variable re-absorption rates of anesthetics. This highlights the necessity of tailored and cautious dosing and administration (Feehan & Packiasabapathy, 2023).
In the procedure of inserting the anesthetic agent, the less dense ligaments of children necessitate a nuanced approach as well. Anesthetists rely on sensation of the needle being inserted and must consider the different ligament density of children. Spinal cord placement varies by age, and importantly, the spinal cord ends at adult levels by 6 years of age (Feehan & Packiasabapathy, 2023). Myelination of the spinal cord can take 12 years, which means a dilute local anesthetic will be more ideal. It will provide a dense block and faster action onset (Feehan & Packiasabapathy, 2023). Additionally, the cardiovascular and respiratory system responses to spinal anesthesia in children differ from those in adults, with minimal hemodynamic suppression noted (Gupta et al., 2014).
Despite undeniable advantages, spinal anesthesia is not devoid of risks in both pediatrics and adults. Inadequate or failed anesthesia, high or total spinal anesthesia, postdural puncture headache, infection, and spinal hematoma constitute potential complications (DeLeon & Wong, 2023). The unique vulnerabilities of the pediatric population accentuate the importance of careful risk assessment and shared discussion with patients and caretakers. While unlikely, children may experience hypotension and desaturation (Gupta et al., 2014). Notably, postdural puncture headaches, though infrequent in children under 10, have been reported in patients as young as 2 years old (Gupta et a., 2014). Patients may also experience transient neurologic symptoms such as pain and dysesthesia (Gupta., et al 2014). If the anesthetist is unable to complete the procedure, then the patient will require general anesthesia.
Another reason spinal anesthesia is underutilized in pediatrics is due to lack of systemic evaluations regarding neurotoxicity of anesthetic agents, particularly in neonates and early infants (Gupta et al., 2014). Part of this is due to the way certain fiber innervations in the spinal cord develop in the postnatal period (Gupta et al., 2014). While available data show that neuraxial agents are safe in neonates and infants, this study was retrospective and participants were not adequately followed-up on (Gupta et al., 2014). Contraindications to pediatric spinal anesthesia are like contraindications for spinal anesthesia in adults, including a history of allergic reactions to the anesthetic (Feehan & Packiasabapathy, 2023).
In conclusion, spinal anesthesia is an effective, low-cost, low-risk technique that is extremely useful yet underutilized in the pediatric population. While it is overall safe and cost-effective, limited dissemination of knowledge and training is a barrier to its broader application. Addressing these challenges, accompanied by comprehensive research into agent neurotoxicity and enhanced training protocols, will lead to increased use of spinal anesthesia in the pediatric population in appropriate situations (Gupta et al., 2014).
References
DeLeon, Alexander DeLeon M, and Cynthia A Wong. “Spinal Anesthesia: Technique.” UpToDate, 17 Mar. 2023, www.uptodate.com/contents/spinal-anesthesia-technique.
Feehan, Thomas, and Senthil Packiasabapathy. “Pediatric Regional Anesthesia – Statpearls – NCBI Bookshelf.” National Library of Medicine, StatPearls Publishing, 7 Feb. 2023, www.ncbi.nlm.nih.gov/books/NBK572106/.
Gupta, Anju, and Usha Saha. “Spinal anesthesia in children: A review.” Journal of anaesthesiology, clinical pharmacology vol. 30,1 (2014): 10-8. doi:10.4103/0970-9185.125687