Airway management in the paediatric difficult intubation registry: a propensity score matched analysis of outcomes over time.

Background: The Paediatric Difficult Intubation Collaborative identified multiple attempts and persistence with direct laryngoscopy as risk factors for complications in children with difficult tracheal intubations and subsequently engaged in initiatives to reduce repeated attempts and persistence with direct laryngoscopy in children. We hypothesised these efforts would lead to fewer attempts, fewer direct laryngoscopy attempts and decrease complications. Methods: Paediatric patients less than 18 years of age with difficult direct laryngoscopy were enrolled in the Paediatric Difficult Intubation Registry. We define patients with difficult direct laryngoscopy as those in whom (1) an attending or consultant obtained a Cormack Lehane Grade 3 or 4 view on direct laryngoscopy, (2) limited mouth opening makes direct laryngoscopy impossible, (3) direct laryngoscopy failed in the preceding 6 months, and (4) direct laryngoscopy was deferred due to perceived risk of harm or poor chance of success. We used a 5:1 propensity score match to compare an early cohort from the initial Paediatric Difficult Intubation Registry analysis (August 6, 2012-January 31, 2015, 785 patients, 13 centres) and a current cohort from the Registry (March 4, 2017-March 31, 2023, 3925 patients, 43 centres). The primary outcome was first attempt success rate between cohorts. Success was defined as confirmed endotracheal intubation and assessed by the treating clinician. Secondary outcomes were eventual success rate, number of attempts at intubation, number of attempts with direct laryngoscopy, the incidence of persistence with direct laryngoscopy, use of supplemental oxygen, all complications, and severe complications. Findings: First-attempt success rate was higher in the current cohort (42% vs 32%, OR 1.5 95% CI 1.3-1.8, p < 0.001). In the current cohort, there were fewer attempts (2.2 current vs 2.7 early, regression coefficient -0.5 95% CI -0.6 to -0.4, p < 0.001), fewer attempts with direct laryngoscopy (0.6 current vs 1.0 early, regression coefficient -0.4 95% CI -0.4 to 0.3, p < 0.001), and reduced persistence with direct laryngoscopy beyond two attempts (7.3% current vs 14.1% early, OR 0.5 95% CI 0.4-0.6, p < 0.001). Overall complication rates were similar between cohorts (19% current vs 20% early). Severe complications decreased to 1.8% in the current cohort from 3.2% in the early cohort (OR 0.55 95% CI 0.35-0.87, p = 0.011). Cardiac arrests decreased to 0.8% in the current cohort from 1.8% in the early cohort. We identified persistence with direct laryngoscopy as a potentially modifiable factor associated with severe complications. Interpretation: In the current cohort, children with difficult tracheal intubations underwent fewer intubation attempts, fewer attempts with direct laryngoscopy, and had a nearly 50% reduction in severe complications. As persistence with direct laryngoscopy continues to be associated with severe complications, efforts to limit direct laryngoscopy and promote rapid transition to advanced techniques may enhance patient safety. Funding: None.

Erector spinae plane blocks: A narrative update.

The erector spinae plane block (ESPB) is perhaps one of the most interesting of the tissue plane blocks described recently. There has been an exponential increase in the number of publications for both adults and children over the past 5 years. Single-shot, intermittent bolus, and continuous infusion techniques have been used effectively. Both the efficacy and safety of the procedure are widely accepted, but the exact mechanism by which the local anesthetic spreads from the tip of the transverse process to block the dorsal and ventral rami of the spinal nerves is controversial and needs clarification. Anatomical differences in children, particularly in neonates and infants, may explain the spread in this age group. In most pediatric studies, erector spinae plane block was opioid sparing, and noninferiority was observed when compared with other regional techniques.

Diagnostic and therapeutic application of thoracic epidural in a child with intractable cardiac arrhythmias: A case report.

A 3-year-old boy presented with episodes of uneasiness and transient loss of consciousness. Atrial tachyarrhythmias with rapid ventricular rate was diagnosed and initially unsuccessfully treated with oral antiarrhythmic drugs. Subsequent Holter monitoring revealed ventricular arrhythmias. Despite pharmacologic treatment, he needed numerous cardioversions. Surgical sympathectomy was planned. Initially, sympathectomy was achieved using a continuous high thoracic epidural block and was performed to ascertain the efficacy of the thoracic sympathectomy. This successfully reduced the ventricular arrhythmias and the need for antiarrhythmic agents. The epidural infusion was also used for pain relief following the subsequent surgical sympathectomy.

Thoracic regional anesthesia and the impact on ventilation.

Thoracic surgical incisions can be associated with intense pain or discomfort. Postoperative thoracic pain may be multifactorial in origin. Inadequate analgesia causes respiratory dysfunction. Adequate analgesia preserves pulmonary function and may hasten recovery. Intravenous opioids are widely used but sufficient analgesia is seldom achieved in doses that permit safe spontaneous ventilation. Thoracic regional anesthesia provides profound analgesia, is opiate sparing and has minimal depressant effects on ventilation. Thoracic regional anesthesia is both an effective alternative to systemic analgesics or can be used as part of a multimodal analgesic technique.

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.

Clonidine as an Adjuvant to Bupivacaine for Suprazygomatic Maxillary Nerve Blocks in Cleft lip and Palate Repair: A Randomized, Prospective, Double-Blind Study.

OBJECTIVES: Does clonidine, as adjuvant to bupivacaine for suprazygomatic maxillary nerve blocks, reduce emergence agitation in patients undergoing cleft lip and cleft palate surgery? DESIGN: Randomized, controlled, and double-blind study. SETTING: Guwahati Comprehensive Cleft Care Center, Guwahati (Assam, India). PARTICIPANTS: A total of 124 patients; with a median age of 5 years in the clonidine group (CLG) and 7 years in the control group (CG), who underwent cleft lip or cleft palate surgery were included. Exclusion criteria included lack of consent from patients or their guardians, allergy to local anesthetics, coagulation disorders, local infection at the puncture site before performing the block, and language difficulties or cognitive disorders. INTERVENTIONS: Patients were randomized into 2 groups to receive bilateral suprazygomatic maxillary nerve blocks with either a bupivacaine/clonidine mixture for the CLG or bupivacaine alone in the CG. MAIN OUTCOME MEASURE: The primary end point was the incidence of emergence agitation. RESULTS: There was a statistically significant difference in the incidence of emergence agitation (30.2% in the CG compared to 15.2% in the CLG; difference of incidences: 15%, 95% CI: 0.1-30.1). The percentage of patients requiring intraoperative Fentanyl was lower in the CLG (10.6% compared to 26.4%; difference of incidences: 15.8%, 95% CI: 1.8-29). No other differences were observed. Further research in a more typically aged children population undergoing cleft surgery is needed. CONCLUSIONS: The use of clonidine as an adjuvant to bupivacaine in maxillary nerve block reduces the incidence of emergence agitation and intraoperative opioid consumption without hemodynamic or sedative side effects in patients undergoing cleft lip and palate surgery.

The utility of ultrasonography in anesthesia management in 3 cases of caudal regression syndrome.

Caudal regression syndrome is an extremely rare clinical entity. It is a challenge to anesthesiologist due to its multisystem involvement. Regional anesthesia literature on caudal regression syndrome is scarce. We report three cases where optimal use of ultrasonography aided in providing satisfactory peri-operative pain relief. Furthermore, a cogent and a logical review of the decision-making processes for the regional blockade in children with caudal regression syndrome are presented.

Variation in pediatric local anesthetic dosing for peripheral nerve blocks: an analysis from the Pediatric Regional Anesthesia Network (PRAN).

BACKGROUND: Variation of local anesthetic dosing has been reported for adult peripheral nerve blocks (PNBs) and infant caudal blocks. As higher doses of local anesthetics (LA) are potentially associated with increased risk of complications (eg, local anesthetic systemic toxicity), it is important to understand the source of LA dose variation. Using the Pediatric Regional Anesthesia Network (PRAN) database, we aimed to determine if variation in dosing exists in pediatric single-injection PNBs, and what factors influence that variation.The primary aim of this study was to determine the factors associated with dosing for the 10 most commonly performed PNBs, with the secondary aim of exploring possible factors for variation such as number of blocks performed versus geographic location. METHODS: The PRAN database was used to determine the 10 most common pediatric PNBs, excluding neuraxial regional anesthetics. The 10 most common pediatric PNBs in the PRAN database were analyzed for variation of LA dose and causes for variation. RESULTS: In a cohort of 34 514 children receiving PNBs, the mean age was 10.38 (+/-5.23) years, average weight was 44.88 (+/-26.66) kg and 61.8% were men. The mean bupivacaine equivalent (BE) dose was 0.86 (+/-0.5) mg kg-1 and ropivacaine was used in 65.4% of blocks. Dose decreases with age (estimate -0.016 (-0.017, -0.015; p<0.001)). In all blocks for all age groups, the range of doses that make up the central 80% of all doses exceeds the mean BE dose for the block. Variation is not related to the number blocks performed at an institution (p=0.33 (CI -0.42 to 0.15)). The dose administered for a PNB is driven in order of impact by the institution where the block was performed (Cohen's ƒ=0.45), then by weight (0.31), type of block (0.27), LA used (0.15) and age (0.03). CONCLUSIONS: Considerable variation in dosing exists in all age groups and in all block types. The most impactful driver of local anesthetic dose is the institution where the block was performed, indicating the dosing of a potentially lethal drug is more based on local culture than on evidence.

The anatomical features of an ultrasound-guided erector spinae fascial plane block in a cadaveric neonatal sample.

BACKGROUND: Since its inception, the erector spinae plane block has been used for a variety of truncal surgeries with success in both adults and children. However, the anatomical features, route of spread, and dermatomal coverage are still not fully understood in a pediatric population. OBJECTIVES: To identify the anatomical features of the erector spinae fascial plane space by replicating an erector spinae plane block in a fresh neonatal cadaveric sample. The primary aim was to determine the spread of the dye within the fascial plane, while the secondary aims were to determine whether the needle direction or entry site affected the spread. METHODS: The block was replicated bilaterally using 0.1 mL/kg of iodinated contrast dye in nine fresh unembalmed preterm neonatal cadavers. The dye was introduced under ultrasound guidance at vertebral level T5 and T8. Additionally, the needle was oriented cranial-caudal vs caudal-cranial to determine if the needle orientation influenced the spread of dye. The block was also replicated midway between the adjacent transverse processes as opposed to the lateral tip of the transverse process to determine the spread. RESULTS: From the total sample size, 14 "blocks" were successfully replicated, while 4 "blocks" were either incomplete or failed blocks. Contrast dye was found in the paravertebral, intercostal, and epidural spaces, including posteriorly over the neural foramina. Results revealed that the needle direction or entry site did not influence the spread within the fascial plane. CONCLUSION: Contrast material was found in the paravertebral, epidural, and intercostal spaces over an average of 5 vertebral levels when using 0.1 mL/kg.

Comparison of Continuous Adductor Canal and Femoral Nerve Blocks for Analgesia and Return of Quadriceps Function After Anterior Cruciate Ligament Reconstruction in Adolescent Patients.

PURPOSE: To compare early pain relief and late quadriceps function after anterior cruciate ligament reconstruction (ACLR) with hamstring autograft in adolescent patients treated with either a continuous femoral nerve block (cFNB) or continuous adductor canal block (cACB). METHODS: We retrospectively reviewed a consecutive series of adolescent patients who underwent ACLR and received either a cACB or cFNB for postoperative pain management. Over a 1-year period, all patients underwent ACLR with cFNBs. Over the subsequent 9 months, all patients underwent their ACLR with cACBs. Patient demographics, postoperative pain scores, opioid consumption, satisfaction and complications, and dates and results of quadriceps function derived at the Return to Sports evaluation were compared. RESULTS: Ninety-one patients (53 cFNB, 38 cACB) were reviewed. There were no differences in the demographics of the 2 groups. There were no statistically significant differences between groups in variations in postoperative pain scores (P = .21), or satisfaction with the blocks (P = .93). Patients in the cFNB group consumed a greater number of opioid doses on postoperative day 3 (2.2 ± 2.1 doses cFNB, 1.1 ± 1.6 doses cACB, P = .03) and a greater number of opioid doses overall for postoperative days 1 to 3 (mean 6.8 ± 5.3 doses cFNB, 3.8 ± 2.1 doses cACB, P = .03). There was no difference in time to return of acceptable quadriceps strength and function when comparing the 2 groups (30.9 ± 7.7 weeks cFNB, 28.9 ± 6.6 weeks cACB, P = .087). CONCLUSIONS: We found few differences in postoperative analgesic requirements when comparing patients who underwent ACLR with hamstring autograft with a cACB to those who underwent a similar procedure with a cFNB. Return of quadriceps strength and function by six months did not appear to vary with regional technique, either cACB or cFNB, employed at surgery. LEVEL OF EVIDENCE: III, Retrospective comparative study.

The extent of cranio-caudal spread within the erector spinae fascial plane space using computed tomography scanning in a neonatal cadaver.

BACKGROUND: The erector spinae plane block (ESP) is a novel approach for blockade of the spinal nerves in infants, children, and adults. Until recently, the gold standard for truncal procedures includes the paravertebral and epidural blocks. However, the exact mechanism by which this blockade is achieved is subject to debate. METHODS: 2.3 mL (1 mL/kg) of iodinated contrast dye was injected bilaterally into the erector spinae fascial plane of a fresh unembalmed preterm neonatal cadaver (weighing 2.3 kg), to replicate the erector spinae plane block and to track the cranio-caudal spread of the contrast dye using computed tomography. The "block" was performed at vertebral level T8 on the right-hand side and at vertebral level T10 on the left-hand side. RESULTS: Contrast dye was spread over three dermatomal levels from T6 to T9 on the right-hand side, while on the left-hand side, the spread was seen over four dermatomal levels from T9 to T11/12. Contrast dye also spread over the costotransverse ligament, into the paravertebral space and further lateral from the lateral border of the erector spinae muscle into the intercostal space. However, no spread was seen in the epidural space. CONCLUSION: The erector spinae plane block is a versatile technique that can be part of the multimodal postoperative analgesic strategy for truncal surgery. In this study, contrast material dye was tracked over four vertebral levels in the paravertebral space (suggesting an approximate volume of 0.5-0.6 mL per dermatome).

A cadaveric study of the erector spinae plane block in a neonatal sample.

BACKGROUND: The aim of this article was to provide a detailed description of the neonatal anatomy related to the erector spinae plane block and to report the spread of the dye within the fascial planes and potential dermatomal coverage. METHODS: Using ultrasound guidance, the bony landmarks and anatomy of the erector spinae fascial plane space were identified. The erector spinae plane block was then replicated unilaterally in two fresh unembalmed neonatal cadavers. Using methylene blue dye, the block was performed at vertebral levels T5-using 0.5 mL in cadaver 1-and T8-using 0.2 mL in cadaver 2. The craniocaudal spread of dye was tracked within the space on the ultrasound screen and further confirmed on dissection. RESULTS: Craniocaudal spread was noted from vertebral levels T3 to T6 when the dye was introduced at vertebral level T5 and from vertebral levels T7 to T11 when the dye was introduced at vertebral level T8. Furthermore, the methylene blue spread was found anteriorly in the paravertebral and epidural spaces, staining both the dorsal and ventral rami of the spinal nerves T2 to T12. Small amounts of dye were also found in the intercostal spaces. CONCLUSION: In two neonatal fresh cadavers, the dye was found to spread to multiple levels and key anatomic locations.

Variation Between and Within Hospitals in Single Injection Caudal Local Anesthetic Dose: A Report From the Pediatric Regional Anesthesia Network.

BACKGROUND: Given that variation exists in health care utilization, expenditure, and medical practice, there is a paucity of data on variation within the practice of anesthesia. The Pediatric Regional Anesthesia Network (PRAN) data lend itself to explore whether different medical practice patterns exist and if there are nerve blocks with more local anesthetic dosing variation than others. The primary aim of this study was to quantify variation in single injection caudal block dosing, and the secondary aim was to explore possible causes for variation (eg, number of blocks performed versus geographic location). METHODS: We queried the PRAN database for single injection caudal blocks in children <1 year of age. Data were analyzed for local anesthetic dose, variation within and across institutions, and possible causes. RESULTS: Mean dose of bupivacaine equivalents per kilogram (BE·kg) among sites ranged from 1.39 to 2.22 with an interdecile range (IDR) containing the mid 80% of all doses ranging from 0.21 to 1.48. Mean dose (BE·kg) was associated with site, age, weight, and local anesthetic used (all P < .0001). Cohen's F effect size estimate was 10 times higher for site (0.65) than for age (0.05) or weight (0.02). Variation (IDR) was not related to number of blocks done at each site (P = .23). Mean volume per kilogram was 0.9± ± 0.2 (mean ± ±standard deviation) and was more strongly associated with site (Cohen's F 0.3) than age (0.04) or weight (0.07). CONCLUSIONS: Wide variation in caudal local anesthetic dosing and administered volume exists. This variation is independent of the number of cases performed at each center but rather is determined by study site (ie, variation between centers) with considerable additional variation within study centers, suggesting additional variability dependent on individual practitioners. While there are legitimate reasons to vary dosing, the current approach is inconsistent and not supported by strong evidence over giving a standardized dose.

Early experience with erector spinae plane blocks in children.

BACKGROUND: An erector spinae plane block is a relatively new regional anesthetic technique. Apart from case reports and small series, the literature regarding pediatric use is limited. AIM: Our objective was to determine the efficacy of the erector spinae plane block in children by measuring the heart rate response to incision. Secondary objectives included feasibility, safety, opioid consumption, and pain scores. Furthermore, we reviewed this block in children published since 2016. STUDY DESIGN: Case Series; Level of evidence, IV. METHODS: With Institutional Review Board approval, a retrospective chart review was conducted on all patients who received erector spinae plane block for surgery between October 2017 and May 2019 at a single institution. Blocks were performed under anesthesia, using ultrasound guidance prior to surgical incision. Block details and hemodynamic and analgesic data were collected. In addition, a PubMed literature review was conducted to identify all erector spinae plane block related publications in patients ≤18 years of age. RESULTS: About 164 patients, 2 days-19.4 years, weighing 2.3-94.7 kg, received erector spinae plane blocks. For more than 79% of single injection blocks, placement time was ≤10 minutes. Using a heart rate increase of <10% at skin incision as criterion, 70.1% of patients had a successful block. Only 20% required long-acting opioids intraoperatively. In a subset of infants who underwent gastrostomy surgery using a dose of 0.5 mL/kg, a local anesthetic spread of at least five dermatomes (0.1 mL/kg/dermatome) was achieved. Per the literature review, 33 publications described erector spinae plane block in 128 children. No complications were reported. CONCLUSION: Erector spinae plane blocks are relatively easy to perform in children with no complications reported to date. The efficacy of the block for a broad spectrum of surgeries, involving incisions from T1 to L4, is encouraging.

Anatomy of the greater occipital nerve block in infants.

BACKGROUND: Pain relief for posterior fossa craniotomies as well as occipital neuralgia, are indications for the use of the greater occipital nerve block in children. The greater occipital nerve originates from the C2 spinal nerve and is accompanied by the occipital artery as it supplies the posterior scalp. AIMS: The aim of this study was to develop a unique, yet simple technique for blocking the greater occipital nerve in children through the evaluation of the anatomy of this nerve and the accompanying occipital artery in the occipital region. METHODS: The greater occipital nerve and occipital artery were dissected and exposed in six formalin-fixed cadavers (five infants [average age of 51.4 days] and one 2-year-old) from the Department of Anatomy, University of Pretoria. Measurements between the nerve and selected bony landmarks were obtained. The relationship between the greater occipital nerve and the occipital artery at the trapezius muscle hiatus was also evaluated. RESULTS: The greater occipital nerve is on average 22.6 ± 5.6 mm from the external occipital protuberance in infants. The average width of the medial three fingers measured at the proximal interphalangeal joint, for each respective cadaver is 20.4 ± 4.0 mm, with a strong correlation coefficient of 0.97 between the aforementioned distances. In 83.3% of the specimens, the occipital artery lies lateral to the greater occipital nerve at the trapezius muscle hiatus. CONCLUSION: In infants, the greater occipital nerve can be blocked approximately 23 mm from the external occipital protuberance, medial to the occipital artery. This distance is equal to the width of the medial three fingers at the proximal interphalangeal joint of the patient.

Comparison between epidural and opioid analgesia for infants undergoing major abdominal surgery.

BACKGROUND: Epidural analgesia is considered optimal for postoperative pain management after major abdominal surgery. The potential to decrease anesthetic and opioid exposure is particularly desirable for infants, given their vulnerability to respiratory depression and concern for anesthetic neurotoxicity. We reviewed our experience with infants undergoing major abdominal surgery to determine if epidural catheter use decreased anesthetic and opioid exposure and improved postoperative analgesia. METHODS: This retrospective cohort study included infants (<12 months) who underwent exploratory laparotomy, ureteral reimplantation, or bladder exstrophy repair between November 2011 and November 2014. Primary outcomes of anesthetic exposure (mean endtidal sevoflurane) and intraoperative opioid administration were compared between infants who received epidural catheters and those who did not. Secondary outcomes included postoperative pain and sedation scores and morphine equivalents administered 0-24 and 24-48 hours after surgery. RESULTS: Of 158 eligible infants, 82 were included and 47 received epidurals. Patients with epidurals underwent bladder exstrophy repair (N = 9), ureteral reimplantation (N = 8), and exploratory laparotomy (N = 30). Infants with epidurals received less intraoperative fentanyl (2.6 mcg/kg (0,4.5) vs 3.3 mcg/kg (2.4,5.8), P = 0.019) and morphine (6% (3/47) vs 26% (9/35), P = 0.014) in univariate analysis. After controlling for age and emergency surgery, differences in long-acting opioid administration persisted, with significantly less morphine given in the epidural group (OR 0.181; 95% CI 0.035-0.925; P = 0.040). Mean endtidal sevoflurane concentrations were similar between groups. There was no significant difference in postoperative median morphine equivalents. CONCLUSION: Placement of epidural catheters in infants undergoing major abdominal surgery is associated with decreased long-acting opioid requirements intraoperatively. Epidural placement does not preclude opioid exposure however, as opioids may be administered for indications other than nociceptive pain in the difficult-to-assess postoperative infant. Further prospective studies are warranted to better quantify the effect of epidural analgesia on intraoperative anesthetic exposure in infants.

Bilateral suprazygomatic maxillary nerve blocks vs. infraorbital and palatine nerve blocks in cleft lip and palate repair: A double-blind, randomised study.

BACKGROUND: Cleft defects are common craniofacial malformations which require early surgical repair. These patients are at high risk of postoperative airway obstruction and respiratory failure. Cleft surgery may require high doses of opioids which may contribute to these complications. OBJECTIVES: To compare the effectiveness of proximal and distal approaches to blocking the maxillary nerve in patients undergoing cleft lip or cleft palate surgery. DESIGN: Randomised, controlled and double-blind study. SETTING: The current study was carried out in Guwahati (Assam, India) between April 2014 and June 2014. PATIENTS: A total of 114 patients older than 6 months who underwent cleft lip or cleft palate surgery were included. Exclusion criteria included coagulation disorders, peripheral neuropathy or chronic pain syndrome, infection in the puncture site, allergy to local anaesthetics, lack of consent and language problems or other barriers that could impede the assessment of postoperative pain. INTERVENTIONS: Patients were randomly assigned to one of two groups: proximal group (bilateral suprazygomatic maxillary nerve blocks) and distal group (bilateral infraorbital nerve blocks for cleft lip repair and bilateral greater and lesser palatine nerve blocks and nasopalatine nerve block for cleft palate surgery). MAIN OUTCOME MEASURE: The primary endpoint was the percentage of patients requiring extra doses of opioids. Secondary endpoints included pain scores, respiratory and nerve block-related complications during the first 24 h. RESULTS: In the intra-operative period, there was a significant reduction of nalbuphine consumption in the proximal group (9.1 vs. 25.4%, P = 0.02). The percentage of patients requiring intra-operative fentanyl was lower in the proximal group (16.4 vs. 30.5%, P = 0.07). There were no differences in either postoperative pain scores or in postoperative complications. No technical failure or block-related complications were reported. CONCLUSION: Bilateral suprazygomatic maxillary nerve block is an effective and safe alternative to the traditional peripheral nerve blocks for cleft lip and cleft palate surgery, in a mixed paediatric and adult population.

Determining the extent of the dural sac for the performance of caudal epidural blocks in newborns.

BACKGROUND: Information regarding the position and relationship of vital structures within the caudal canal is important for anesthesiologists who perform a caudal block. This information can be acquired by anatomical dissection, with ultrasound technology, or radiological studies. AIMS: The aim of this study was to determine the position of the dural sac in neonates by measuring the distance of the termination of the dural sac from the apex of the sacral hiatus in neonatal cadavers. METHODS: After careful dissection, the distance from the apex of the sacral hiatus to the dural sac was measured in a sample of neonatal cadavers. RESULTS: In 39 neonatal cadavers, the mean distance from the apex of the sacral hiatus to the dural sac was 10.45 mm. The range of this distance was between 4.94 and 26.28 mm. The mean distance for females was 9.64 mm (range from 6.66 to 15.09); that for males was 10.90 mm (range between 4.94 and 26.28). Linear regression with the log of this distance as the outcome variable gave an estimated 3.3% increase in the distance for each 1 cm increase in the length of the neonate (95% CI for this proportion was 1.91-4.71). CONCLUSION: Anesthesiologists should be aware of the short distance between the sacral hiatus and the dural sac when performing caudal blocks, the shortest distance was 4.94 mm. Armed with this knowledge, caudal techniques should be modified to improve the safety and reduce the risk of complications, such as dural puncture.