Spinal Anesthesia in Children and Adolescents
Indications: Lower extremity, pelvic, and abdominal surgery
Special considerations: Surgical spinal anesthesia offers many benefits in the pediatric population. It is a powerful opioid-free or opioid-sparing non-triggering anesthetic that is hemodynamically stable, with minimal emergence delirium and minimal PONV. Benefits include hemodynamic stability, less airway instrumentation, fewer respiratory complications, diminished surgical stress response and less emergence delirium compared with general anesthesia.
Dosing: Recommendations from the 2018 ESRA/ASRA guidelines on local anesthesia dosing in children stipulated a bupivacaine dosing regimen for pediatric spinals. The bupivacaine dosing recommended decreases with increasing age. Tetracaine can also be used. Recently, we published our experience using isobaric mepivacaine and chloroprocaine for spinals in patients under age 18.
Bupivicaine Dosing:
< 5kg: 1mg/kg
5-10 kg: 0.5mg/kg
10-15kg: 0.4mg/kg
> 15kg: 0.3mg/kg
Coverage: Isobaric bupivacaine will produce a lumbosacral dermatomal coverage at the level of the spinal placement. Hyperbaric bupivacaine is used to achieve higher thoracic levels.
Considerations: Patients should have full resolution of the spinal and pass a trial of void prior to discharge from the PACU. The PACU stay may be prolonged relative to general anesthesia by inability to void or delayed resolution of the spinal. Emergence delirium is typically absent, perhaps due to TIVA.
Contraindications:
Absolute: Patient or parental refusal, Infection at site of injection, Bacteremia, Allergy to LA, Increased ICP
Relative: Coagulopathy, Sepsis, Indeterminate neurological disease, Presence of intrathecal pumps, VP shunts or other hardware, Tethered cord, Anatomic disorders of the spine, History of spinal instrumentation and fusion, Dorsal rhizotomy
Complications: Notable side effects include soreness at puncture site, postoperative urinary retention and PDPH, although PDPH is uncommon with the use of 27g pencil-point needles. Serious complications such as infection or spinal cord injury are extremely rare. Other risks of spinal anesthesia include failure and conversion to GA, high spinal, apnea, local anesthesia systemic toxicity, backache, meningitis, hematoma, arachnoiditis, spinal cord ischemia, permanent neurological damage and death from direct needle trauma or medication error.
Anatomic boundaries
The iliac crest is an accepted landmark for the level of the spinal anesthesia. In children, the intercristal line crosses L4-L5, and in adults L3-L4. The spinal cord ends at T12/L1 in children, and L1 or L1/L2 in adolescents and adults. Ultrasound can be used in real-time or prior to placement of the spinal for the identification of landmarks. A midline technique typically requires less sedation than a paramedian technique.
Babies have a proportionately smaller pelvis than adults, and the sacrum is higher in relation to the iliac crests. Because of this, the intercristal line in infants crosses at L5-S1, before moving with growth of the child to L4-5 in children and L3-4 in the adult. In adults and children, the spinal cord ends at L1, whereas in infants it ends at L3. In adults, the dural sac ends at S1, whereas in infants it ends at S3.
In adults, there is 2ml/kg of cerebro-spinal fluid (CSF), whereas in infants, there is 4ml/kg of CSF. That, compared with the proportionally increased blood flow to the spinal cord, is suspected to be why infants require larger doses on a mg/kg basis than older children and adults.
In adults, there is 2ml/kg of cerebro-spinal fluid (CSF), whereas in infants, there is 4ml/kg of CSF. That, compared with the proportionally increased blood flow to the spinal cord, is suspected to be why infants require larger doses on a mg/kg basis than older children and adults.
Technique: While IVs in infant spinal anesthesia are sometimes placed after spinal, IV placement prior to spinal anesthesia in children and adolescents is customary as sedation is required. IV sedation or continuation of volatile anesthetic is titrated to effect for placement of the spinal, and then reduced for the maintenance phase.
Chlorhexidine is recommended over povidone iodine. A 27g non-cutting spinal needle will reduce the risk of post-dural puncture headache (PDPH) compared to larger gauge, cutting needles. In smaller patients, extra care must be taken to avoid an accidental dural puncture with the local or introducer needle. A combined-spinal epidural (CSE) technique can also be performed as in adult patients, with special care given to avoiding unintended dural puncture with the epidural needle to avoid PDPH (8).
Positioning (Seated)
Monitors, oxygen administration, and sedation are initiated. A pillow is placed in the patient’s lap, and arms wrapped around the pillow to support both the arms and the head. The anesthesiologist and an assistant stand on either side of the bed and help sit the patient up straight on the OR table, with legs outstretched. The foot of the bed can be lowered 30 degrees to aid with patient comfort. An assistant stands on the side of the bed in front of the patient to hold the patient and help coach them through the procedure. Care is taken to avoid corneal abrasions in sedated patients.
Positioning (Lateral Recumbent)
For smaller children or patients who need deeper sedation, lateral position is preferable. Monitoring, oxygen administration, and sedation are initiated. An assistant stands on the side of the bed to face the patient and hold the legs and head. After turning lateral decubitus, the head, hips and knees are flexed.
The Consensus Practice Guidelines on Postdural Puncture Headaches published a summary report in 2023 that showed there is moderate evidence in adults that the lateral decubitus position may decrease the risk of postdural puncture headache in adults, but this has not been adequately studied in children. This must be considered in the context that spinal anesthesia is typically considered easier to perform in the sitting position, as the group also found that increased number of attempts is associated with increased risk of PDPH.
In 2022, Rebollar et al published a series of 200 cases of spinal anesthesia in children aged 8 days -13 years. They used procedural sedation to provide optimal conditions. They performed spinal anesthesia using a 22 or 25 g needle with bupivacaine. They report a success rate of 97.5%, with a complication rate of 2%: 2 patients had a desaturation event < 90%, and 2 patients developed PDPH that were successfully managed with hydration, rest, and analgesics. They note that their failure rate reduced to zero after the introduction of pre-procedure ultrasound.
An older series of spinal anesthesia from 2004, published by Puncuh and Kokki, reported on 1132 spinals in children aged 6 months to 14 years. They similarly found a low complication rate with an incidence of hypotension of 17/1132 children, 5 children developing a PDPH, and 9 children developing a backache.
There are several studies that have established the safety of spinal anesthetics in children generally both here and abroad, including ADARPEF, the National Pediatric Epidural Audit, and PRAN.
The most recent data from PRAN reported on 2,000 spinal anesthetics, with most of those being in the age group of 10 and older. There was one case of intraoperative apnea in an infant and one case of LAST in a 2-month-old. There were no permanent neurologic deficits reported, with an incidence of 0.3-0.4/10,000. Most neuraxial complications in this dataset were epidural complications, including unintended dural puncture during epidural placement or catheter complications including 1 epidural abscess. There were no hematomas reported with spinal anesthetics or epidurals. No cases of meningitis were reported.
ADARPEF was a one-year prospective survey of regional anesthesia in children. This study included a total of 387 spinals. There were no complications that resulted in sequelae one year out. 2 ex-pre-term babies, aged 1 and 3 months, had high spinals requiring mechanical ventilation. The rest of the neuraxial complications were the result of caudal or lumbar epidurals. There were no complications from spinals reported in older children, which were the majority of the spinals placed.
DelPizzo et al published a study in Anesthesia and Analgesia titled ‘Risk of postdural puncture headache in adolescents and adults.” They prospectively followed 656 patients after spinal anesthesia with a 27g Whitacre needle and compared two groups: patients aged 12-19 years old and 20-45 years old. They found that teenagers were 3 times as likely to develop a postdural puncture headache, although the risk was still low. Adults had a risk of 1.8%, while teenagers had a risk of 4.9%. Although this is a three-fold increase in risk, the symptoms were mild and resolved with conservative management. None of the teenagers required an epidural blood patch. Patients who didn’t get a PDPH were more satisfied with their anesthetic and more likely to say they would be willing to accept this type of anesthesia again.
Suresh S, Ecoffey C, Bosenberg A, Lonnqvist PA, de Oliveira GS Jr, de Leon Casasola O, de Andrés J, Ivani G. The European Society of Regional Anaesthesia and Pain Therapy/American Society of Regional Anesthesia and Pain Medicine Recommendations on Local Anesthetics and Adjuvants Dosage in Pediatric Regional Anesthesia. Reg Anesth Pain Med. 2018 Feb;43(2):211-216. doi: 10.1097/AAP.0000000000000702. PMID: 29319604.
Carley M, Sheetz M, Lauzadis J, Zhong H, DelPizzo K. Mepivacaine dosing for spinal anesthesia in pediatric orthopedic surgery: a retrospective chart review. Reg Anesth Pain Med. 2024 Feb 2:rapm-2023-105093. doi: 10.1136/rapm-2023-105093. Epub ahead of print. PMID: 38307613.
Uppal V, Russell R, Sondekoppam R, et al. Consensus Practice Guidelines on Postdural Puncture Headache From a Multisociety, International Working Group: A Summary Report. JAMA Netw Open.2023;6(8):e2325387. doi:10.1001/jamanetworkopen.2023.25387
Eizaga Rebollar R, García Palacios MV, Morales Guerrero J, Torres Morera LM. Pediatric spinal anesthesia at a tertiary care hospital: Eleven years after. Paediatr Anaesth. 2022 May;32(5):617-624. doi: 10.1111/pan.14414. Epub 2022 Feb 22. PMID: 35156263.
Puncuh F, Lampugnani E, Kokki H. Use of spinal anaesthesia in paediatric patients: a single centre experience with 1132 cases. Paediatr Anaesth. 2004;14(7):564-567. doi:10.1111/j.1460-9592.2004.01240.x
Llewellyn N, Moriarty A. The national pediatric epidural audit. Paediatr Anaesth. 2007 Jun;17(6):520-33. doi: 10.1111/j.1460-9592.2007.02230.x. PMID: 17498013.
Giaufré E, Dalens B, Gombert A. Epidemiology and morbidity of regional anesthesia in children: a one-year prospective survey of the French-Language Society of Pediatric Anesthesiologists. Anesth Analg. 1996 Nov;83(5):904-12. doi: 10.1097/00000539-199611000-00003. PMID: 8895261.
Walker BJ, et al; Pediatric Regional Anesthesia Network Investigators. Complications in Pediatric Regional Anesthesia: An Analysis of More than 100,000 Blocks from the Pediatric Regional Anesthesia Network. Anesthesiology. 2018 Oct;129(4):721-732. doi: 10.1097/ALN.0000000000002372. PMID: 30074928.
DelPizzo K, Luu T, Fields KG, et al. Risk of Postdural Puncture Headache in Adolescents and Adults. Anesth Analg. 2020;131(1):273-279. doi:10.1213/ANE.0000000000004691
Ecoffey C, Bosenberg A, Lonnqvist PA, Suresh S, Delbos A, Ivani G. Practice advisory on the prevention and management of complications of pediatric regional anesthesia. J Clin Anesth. 2022;79:110725. doi:10.1016/j.jclinane.2022.110725
Eizaga Rebollar R, García Palacios MV, Morales Guerrero J, Torres Morera LM. Pediatric spinal anesthesia at a tertiary care hospital: Eleven years after. Paediatr Anaesth. 2022;32(5):617-624. doi:10.1111/pan.14414
Van Schoor AN, Bosman MC, Bosenberg AT. Descriptive study of the differences in the level of the conus medullaris in four different age groups. Clin Anat. 2015;28(5):638-644. doi:10.1002/ca.22505