BACKGROUND:Posterior spinal fusion to correct adolescent idiopathic scoliosis is associated with significant postoperative pain. Different modalities have been reported as part of a multimodal analgesic plan. Intravenous methadone acts as a mu-opioid agonist and N-Methyl-D-aspartate (NMDA) antagonist and has been shown to have opioid-sparing effects. Our multimodal approach has included hydromorphone patient-controlled analgesia (PCA) with and without preincisional methadone, and recently postoperative methadone without a PCA.AIMS:We hypothesized that a protocol including scheduled postoperative methadone doses would reduce opioid usage compared to PCA-based strategy.METHODS:A retrospective chart review of patients undergoing posterior spinal fusion for adolescent idiopathic scoliosis between 2015 and 2020 was performed. There were three patient groups: Group PCA received a hydromorphone PCA without methadone; Group PCA + Methadone received preincisional methadone and a hydromorphone PCA; Group Methadone received preincisional methadone, scheduled postoperative methadone, and no PCA. The primary outcome was postoperative opioid use over 72 h. Secondary outcomes included pain scores, sedation scores, and length of stay.RESULTS:Group PCA (n = 26) consumed 0.33 mg/kg (95% CI [0.28, 0.38]) total hydromorphone equivalents, Group PCA + methadone (n = 39) 0.30 mg/kg (95% CI [0.25, 0.36]) total hydromorphone equivalents, and Group methadone (n = 22) 0.18 mg/kg (95% CI [0.15, 0.21]) total hydromorphone equivalents (p = .00096). There were no statistically significant differences between the groups for secondary outcomes.CONCLUSION:A protocol with intraoperative and scheduled postoperative methadone doses resulted in a 45% reduction in opioid usage compared to a PCA-based protocol with similar analgesia after pediatric posterior spinal fusion.

BACKGROUND: Neuromodulation is a commonly used technique in adult pain management, with current off-label use of peripheral nerve stimulators for the treatment of occipital neuralgia. This targeted therapy can help avoid systemic medications and treat refractory symptoms. CASE REPORT: We present a 17-year-old boy with significant lesser occipital neuralgia and hydrocephalus status post ventriculoperitoneal shunt placement. He had occipital neuralgia treatment failures with both medication trials and surgical decompression in conjunction with physical and psychological therapies, eventually requiring weekly lesser occipital nerve blocks for pain relief. Our patient experienced a substantial reduction in pain and increase in functional recovery after the placement of a permanent peripheral nerve stimulator without disruption of his ventriculoperitoneal shunt. CONCLUSION: Peripheral nerve stimulator implantation can be safe and efficacious for the treatment of refractory occipital neuralgia in a pediatric patient with an ipsilateral ventriculoperitoneal shunt. KEY WORDS: Peripheral nerve stimulation, occipital neuralgia, pediatric, chronic pain, neuromodulation

The importance of nitric oxide (NO) in regulating cerebral blood flow (CBF) remains unresolved, due in part to methodological approaches, which lack a comprehensive assessment of both global and regional effects. Importantly, NO synthase (NOS) expression and activity appear greater in some anterior brain regions, suggesting region-specific NOS influence on CBF. We hypothesized that NO contributes to basal CBF in healthy adults, in a regionally distinct pattern that predominates in the anterior circulation. Fourteen healthy adults (7 females; 24 +/- 5 years) underwent two magnetic resonance imaging (MRI) study visits with saline (placebo) or the NOS inhibitor, L-NMMA, administered in a randomized, single-blind approach. 4D flow MRI quantified total and regional macrovascular CBF, whereas arterial spin labelling (ASL) MRI quantified total and regional microvascular perfusion. L-NMMA (or volume-matched saline) was infused intravenously for 5 min prior to imaging. L-NMMA reduced CBF (L-NMMA: 722 +/- 100 vs. placebo: 771 +/- 121 ml/min, P = 0.01) with similar relative reductions (5-7%) in anterior and posterior cerebral circulations, due in part to the reduced cross-sectional area of 9 of 11 large cerebral arteries. Global microvascular perfusion (ASL) was reduced by L-NMMA (L-NMMA: 42 +/- 7 vs. placebo: 47 +/- 8 ml/100g/min, P = 0.02), with 7-11% reductions in both hemispheres of the frontal, parietal and temporal lobes, and in the left occipital lobe. We conclude that NO contributes to macrovascular and microvascular regulation including larger artery resting diameter. Contrary to our hypothesis, the influence of NO on cerebral perfusion appears regionally uniform in healthy young adults. Key points Cerebral blood flow (CBF) is vital for brain health, but the signals that are key to regulating CBF remain unclear. Nitric oxide (NO) is produced in the brain, but its importance in regulating CBF remains controversial since prior studies have not studied all regions of the brain simultaneously. Using modern MRI approaches, a drug that inhibits the enzymes that make NO (L-NMMA) reduced CBF by up to 11% in different brain regions. NO helps maintain proper CBF in healthy adults. These data will help us understand whether the reductions in CBF that occur during ageing or cardiovascular disease are related to shifts in NO signalling.

Background: Overuse and misuse of opioids is a continuing crisis. The most common reason for children to receive opioids is postoperative pain, and they are often prescribed more than needed. The amount of opioids prescribed varies widely, even for minor ambulatory procedures. This study uses a large national sample to describe filled opioid prescriptions to preteen patients after all ambulatory surgical procedures and common standard procedures. Methods: We analyzed Truven Health MarketScan data for July 2012 through December 2016 to perform descriptive analyses of opioid fills by age and geographic area, change over time, second opioid fills in opioid-naive patients, and variation in the types and amount of medication prescribed for 18 common and standard procedures in otolaryngology, urology, general surgery, ophthalmology, and orthopedics. Results: Over 10% of preteen children filled perioperative opioid prescriptions for ambulatory surgery in the period 2012 to 2016. The amount prescribed varied widely (median 5 days' supply, IQR 3-8, range 1 -90), even for the most minor procedures, for example, frenotomy (median 4 days' supply, IQR 2-5, range 1-60). Codeine fills were common despite safety concerns. Second opioid prescriptions were filled by opioid-naive patients after almost all procedures studied. The rate of prescribing declined significantly over time and varied substantially by age and across census regions. Conclusions: We identified opioid prescribing outside of the norms of standard practice in all of the specialties studied. Standardizing perioperative opioid prescribing and developing guidelines on appropriate prescribing for children may reduce the opioids available for misuse and diversion. (c) 2021 Elsevier Inc. All rights reserved.

Central adiposity is associated with greater sympathetic support of blood pressure. β-adrenergic receptors (β-AR) buffer sympathetically mediated vasoconstriction and β-AR-mediated vasodilation is attenuated in preclinical models of obesity. With this information, we hypothesized β-AR vasodilation would be lower in obese compared with normal weight adults. Because β-AR vasodilation in normal weight adults is limited by cyclooxygenase (COX) restraint of nitric oxide synthase (NOS), we further explored the contributions of COX and NOS to β-AR vasodilation in this cohort. Forearm blood flow (FBF, Doppler ultrasound) and mean arterial blood pressure (MAP, brachial arterial catheter) were measured and forearm vascular conductance (FVC) was calculated (FVC = FBF/MAP). The rise in FVC from baseline (ΔFVC) was quantified during graded brachial artery infusion of isoproterenol (Iso, 1-12 ng/100 g/min) in normal weight (n = 36) and adults with obesity (n = 22) (18-40 yr old). In a subset of participants, Iso-mediated vasodilation was examined before and during inhibition of NOS [NG-monomethyl-l-arginine (l-NMMA)], COX (ketorolac), and NOS + COX (l-NMMA + ketorolac). Iso-mediated increases in FVC did not differ between groups (P = 0.57). l-NMMA attenuated Iso-mediated ΔFVC in normal weight (P = 0.03) but not adults with obesity (P = 0.27). In normal weight adults, ketorolac increased Iso-mediated ΔFVC (P < 0.01) and this response was lost with concurrent l-NMMA (P = 0.67). In contrast, neither ketorolac (P = 0.81) nor ketorolac + l-NMMA (P = 0.40) altered Iso-mediated ΔFVC in adults with obesity. Despite shifts in COX and NOS, β-AR vasodilation is preserved in young adults with obesity. These data highlight the presence of a compensatory shift in microvascular control mechanisms in younger humans with obesity.NEW & NOTEWORTHY We examined β-adrenergic receptor-mediated vasodilation in skeletal muscle of humans with obesity and normal weight. Results show that despite shifts in the contribution of cyclooxygenase and nitric oxide synthase, β-adrenergic-mediated vasodilation is relatively preserved in young, otherwise healthy adults with obesity. These data highlight the presence of subclinical changes in microvascular control mechanisms early in the obesity process and suggest duration of obesity and/or the addition of primary aging may be necessary for overt dysfunction.

Microvascular cerebral perfusion (CP) is critical for adequate oxygenation of neuronal tissue in the brain. However, the mechanisms underlying proper CP regulation in humans have yet to be fully defined. Endothelin is a potent endogenous vasoconstrictor and appears to have a modest role in blood flow regulation in many peripheral vascular beds in healthy individuals. We tested the hypothesis that endothelin receptor antagonism will not influence CP in healthy young adults. Six male subjects (age: 24±4 yrs; BMI: 23±2 kg/m2) participated in the single‐blind study in which endothelin receptor antagonist (Ambrisentan, 10 mg) or placebo was administered orally. Only males participated in the current study due to potential teratogenic effects of Ambrisentan. Resting CP was quantified via 3T MRI using pseudo‐continuous arterial spin labeling (ASL) normalized to gray matter volume approximately 120 minutes following dosing. Blood pressure, heart rate, and end‐tidal CO2 were monitored. Data were analyzed via paired t‐tests and reported as mean±SD. Significance was taken as p≤0.05. Heart rate (57±8 vs. 59±7 bpm), mean arterial pressure (81±7 vs. 79±8 mmHg) and end‐tidal CO2 (34±6 vs. 37±3 mmHg) was not different between placebo and Ambrisentan, respectively (all p>0.05). Compared to placebo, Ambrisentan increased cerebral perfusion (31±3 vs. 34±2 mL/100g/min; p<0.05), representing a 8±5% increase. Regionally, Ambrisentan demonstrated a tendency to increase CP in brain regions supplied by the anterior cerebral circulation (frontal lobe: 36±11 vs. 45±5 mL/100g/min, p=0.05; parietal lobe: 35±10 vs. 43±5 mL/100g/min, p=0.08; temporal lobe: 35±10 vs. 43±6 mL/100g/min, p=0.07; basal ganglia: 35±9 vs. 41±5, p=0.09; cingulate: 39±10 vs. 47±5 mL/100g/min, p=0.08). In contrast, CP in regions supplied by the posterior circulation did not increase to a similar extent (occipital lobe: 37±9 vs. 43±7 mL/100g/min, p=0.13; cerebellum 30±16 vs. 38±6 mL/100g/min, p=0.27). Contrary to our hypothesis, these data suggest endothelin contributes to resting CP by increasing microvascular tone, an effect that may be more pronounced in the anterior brain regions. These preliminary findings contribute to resolving potential mechanisms mediating normal CP in healthy individuals and form the basis of future studies exploring the influence of elevated endothelin signaling in conditions like diabetes or heart failure.Support or Funding InformationADA 1‐16‐ICTS‐099

Minimally invasive repair of pectus excavatum (Nuss procedure) is associated with significant pain, and efforts to control pain impact resource utilization. Bilateral thoracic intercostal nerve cryoablation has been proposed as a novel technique to improve post-operative pain control, though the impact on hospital cost is unknown.METHODS:We conducted a retrospective study of patients undergoing a Nuss procedure from 2016 to 2019. Patients who received cryoablation were compared to those that received traditional pain control (patient-controlled analgesia or epidural). Outcome variables included postoperative opioid usage (milligram morphine equivalents, MME), length of stay (LOS), and hospital cost.RESULTS:Thirty-five of 73 patients studied (48%) received intercostal nerve cryoablation. LOS (1.0 vs 4.0 days, p < 0.01) and total hospital cost ($21,924 versus $23,694, p = 0.04) were decreased in the cryoablation cohort, despite longer operative time (152 vs 74 min, p < 0.01). Cryoablation was associated with decreased opioid usage (15.0 versus 148.6 MME, p < 0.01) during the 24 h following surgery and this persisted over the entire postoperative period, including discharge opioid prescription (112.5 vs 300.0 MME, p < 0.01).CONCLUSION:Bilateral intercostal nerve cryoablation is associated with decreased postoperative opioid usage and decreased resource utilization in pediatric patients undergoing a minimally invasive Nuss procedure for pectus excavatum.LEVEL OF EVIDENCE:Retrospective comparative study, level III.

Endothelin‐1 (ET‐1) is a potent vasoconstrictor that regulates vascular tone by binding to the ETA receptors on vascular smooth muscle. In healthy humans, blockade of ETA receptors increases resting forearm blood flow. ET‐1 appears to contribute to poor outcomes in animal models of cerebral ischemia, but the role of ET‐1 signaling in control of basal cerebral blood flow (CBF) in healthy adults is unknown. Interestingly, ET‐1 is upregulated in insulin resistance (IR) and resting CBF is reduced primarily in the anterior circulation, which may be due to enhanced ET‐1 signaling. We hypothesized: 1) ETA receptor blockade would increase CBF more in adults with IR, but play little to no role in regulating CBF in healthy adults and 2) ETA blockade would increase CBF more in the anterior than posterior circulation. Healthy normal weight adults (Control; n=6; BMI 23±2 kg/m2; age 24±4 yrs) and adults with Metabolic Syndrome (MetSyn; n=4; BMI 34±8 kg/m2; age 25±12 yrs) underwent magnetic resonance imaging (MRI) study visits. A subset of subjects completed a second MRI study visit (Control, n=6; MetSyn, n=2) with ETA blockade (10mg oral Ambrisentan). Phase‐contrast vastly undersampled isotropic projection reconstruction (PCVIPR) MRI was used to quantify total and regional CBF (CBF= blood velocity• artery cross sectional area). CBF in the anterior circulation was represented as the sum of CBF in the left and right internal carotid arteries (ICA) whereas CBF in the posterior circulation was represented by the basilar artery (BA). Total CBF was taken as the sum of flow in the left and right ICAs and BA. Heart rate (HR), mean arterial pressure (MAP), and end‐tidal CO2 (ETCO2) were monitored. Significance was determined using a mixed two‐way ANOVA or one‐way ANOVA and significance was set at p≤0.05. Results are mean±SD. HR, MAP, and ETCO2 were similar between Control and MetSyn (p>0.05) and did not change with Ambrisentan in either group (p>0.05). Resting total CBF was higher in Control compared to MetSyn (Control 704±87 vs. MetSyn 487±44 mL/min, p<0.05). Ambrisentan did not change total CBF (p>0.05). Resting anterior CBF was similar between groups (Control 535±82 vs. MetSyn 460±26 mL/min, p>0.05), and was unchanged by Ambrisentan (p>0.05). Resting posterior CBF was higher in Control compared to MetSyn (Control 168±33 vs. MetSyn 127±18 mL/min, p<0.05) and Ambrisentan increased posterior CBF (main effect of Ambrisentan, p=0.05); however, the absolute and relative change in posterior CBF was similar between groups (%ΔCBF Control 9±15 vs. MetSyn 11±8% p>0.05). IR adults exhibited lower resting total and posterior CBF compared to healthy adults. Contrary to our hypothesis, Ambrisentan did not increase total or anterior CBF in IR. Surprisingly, Ambrisentan increased CBF in the posterior circulation of healthy and IR adults similarly. Therefore, ET‐1 signaling appears to play a role in regulating vascular tone in the posterior region, however, IR adults do not exhibit enhanced sensitivity to ET‐1. A longer duration or increased severity of IR may be needed to alter cerebrovascular responses to ET‐1 signaling.Support or Funding InformationADA1‐16‐ICTS‐099

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.

INTRODUCTION:Postoperative pain control remains the primary reason for inpatient stay after minimally invasive repair of pectus excavatum. In a previous study, our group reported that early pain control was better in patients managed with a thoracic epidural, while late pain control was better in patients managed with patient-controlled analgesia (PCA). After revising our epidural transition and modifying the PCA protocol, we conducted a multi-institutional prospective randomized trial to evaluate these two pain control strategies. MATERIALS AND METHODS:Patients were randomized to epidural or PCA following minimally invasive repair of pectus excavatum with standard protocols for each arm. Primary outcome was length of stay with secondary variables including mean patient pain scores, complications, and parental satisfaction. Scores were pooled for the two groups and reported as means with standard deviation. Results were compared using t-tests and one-way analysis of variance with p-value < 0.05 determining significance. RESULTS:Sixty-five patients were enrolled, 32 epidural and 33 PCA. Enrollment was stopped early when we developed an alternative strategy for controlling these patients' pain. There was no difference in length of stay in hours between the two arms; epidural 111.3 ± 18.5 versus PCA 111.4 ± 51.4, p = 0.98. Longer operative time was found in the epidural group. Nine patients in the epidural group (28%) required a PCA in addition to epidural for adequate pain control. Mean pain scores were lower on postoperative day 0 in the epidural group compared with the PCA groups, but were otherwise similar. CONCLUSION:In our prospective randomized trial, PCA is just as effective as thoracic epidural in decreasing early postoperative pain scores after minimally invasive repair of pectus excavatum.

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−1) 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−1) 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.

BACKGROUND:To evaluate the relative research productivity and ranking of anesthesiology departments in Canada and the United States, using the Hirsch index (h-index) and 4 other previously validated metrics.METHODS:We identified 150 anesthesiology departments in Canada and the United States with an accredited residency program. Publications for each of the 150 departments were identified using Thomson's Institute for Scientific Information Web of Science, and the citation report for each department was exported. The bibliometric data were used to calculate publication metrics for 3 time periods: cumulative (1945-2014), 10 years (2005-2014), and 5 years (2010-2014). The following group metrics were then used to determine the publication impact and relative ranking of all 150 departments: h-index, m-index, total number of publications, sum of citations, and average number of citations per article. Ranking for each metric were also stratified by using a proxy for departmental size. The most common journals in which US and Canadian anesthesiology departments publish their work were identified.RESULTS:The majority (23 of the top 25) of top-ranked anesthesiology departments are in the United States, and 2 of the top 25 departments (University of Toronto; McGill University) are in Canada. There was a strong positive relationship between each of h-index, total number of publications, and the sum of citations (0.91-0.97; P < .0001). Departmental size correlates with increased academic productivity on most metrics. The most frequent journals in which US and Canadian anesthesiology departments publish are Anesthesiology, Anesthesia and Analgesia, and the Canadian Journal of Anesthesia.CONCLUSIONS:Our study ranked the Canadian and US anesthesiology departmental research productivity using the h-index applied to each department, total number of publications, total number of citations, and average number of citations. The strong relationship between the h-index and both the number of publications and number of citations of anesthesiology departments shows that the departments with the highest number of publications are also producing research with the most highly cited articles (ie, most impact), as demonstrated by the h-index.

BackgroundWith over 230 million surgical procedures performed annually worldwide, better application of evidence in anesthesia and perioperative medicine may reduce widespread variation in clinical practice and improve patient care. However, a comprehensive summary of the complete available evidence has yet to be conducted. This scoping review aims to map the existing literature investigating perioperative anesthesia interventions and their potential impact on patient mortality, to inform future knowledge translation and ultimately improve perioperative clinical practice.MethodsSearches were conducted in MEDLINE, EMBASE, CINAHL, and the Cochrane Library databases from inception to March 2015. Study inclusion criteria were adult patients, surgical procedures requiring anesthesia, perioperative intervention conducted/organized by a professional with training in anesthesia, randomized controlled trials (RCTs), and patient mortality as an outcome. Studies were screened for inclusion, and data was extracted in duplicate by pairs of independent reviewers. Data were extracted, tabulated, and reported thematically.ResultsAmong the 10,505 publications identified, 369 RCTs (n=147,326 patients) met the eligibility criteria. While 15 intervention themes were identified, only 7 themes (39 studies) had a significant impact on mortality: pharmacotherapy (n=23), nutritional (n=3), transfusion (n=4), ventilation (n=5), glucose control (n=1), medical device (n=2), and dialysis (n=1).ConclusionsBy mapping intervention themes, this scoping review has identified areas requiring further systematic investigation given their potential value for reducing patient mortality as well as areas where continued investment may not be cost-effective given limited evidence for improving survival. This is a key starting point for future knowledge translation to optimize anesthesia practice.

Background: Complications in pediatric regional anesthesia are rare, so a large sample size is necessary to quantify risk. The Pediatric Regional Anesthesia Network contains data on more than 100,000 blocks administered at more than 20 children's hospitals. This study analyzed the risk of major complications associated with regional anesthesia in children. Methods: This is a prospective, observational study of routine clinical practice. Data were collected on every regional block placed by an anesthesiologist at participating institutions and were uploaded to a secure database. The data were audited at multiple points for accuracy. Results: There were no permanent neurologic deficits reported (95% CI, 0 to 0.4: 10,000). The risk of transient neurologic deficit was 2.4: 10,000 (95% CI, 1.6 to 3.6: 10,000) and was not different between peripheral and neuraxial blocks. The risk of severe local anesthetic systemic toxicity was 0.76: 10,000 (95% CI, 0.3 to 1.6: 10,000); the majority of cases occurred in infants. There was one epidural abscess reported (0.76: 10,000, 95% CI, 0 to 4.8: 10,000). The incidence of cutaneous infections was 0.5% (53: 10,000, 95% CI, 43 to 64: 10,000). There were no hematomas associated with neuraxial catheters (95% CI, 0 to 3.5: 10,000), but one epidural hematoma occurred with a paravertebral catheter. No additional risk was observed with placing blocks under general anesthesia. The most common adverse events were benign catheter-related failures (4%). Conclusions: The data from this study demonstrate a level of safety in pediatric regional anesthesia that is comparable to adult practice and confirms the safety of placing blocks under general anesthesia in children.

Key Clinical Message Acute liver dysfunction in the perioperative period may increase the risk of epidural hematoma in a patient with a neuraxial catheter. Coagulation testing needs to be carefully monitored in these patients. An epidural hematoma should be ruled out urgently by CT or MRI in cases of a persistent motor block.

BACKGROUND To evaluate the relative research productivity and ranking of anesthesiology departments in Canada and the United States, using the Hirsch index (h-index) and 4 other previously validated metrics. METHODS We identified 150 anesthesiology departments in Canada and the United States with an accredited residency program. Publications for each of the 150 departments were identified using Thomson's Institute for Scientific Information Web of Science, and the citation report for each department was exported. The bibliometric data were used to calculate publication metrics for 3 time periods: cumulative (1945-2014), 10 years (2005-2014), and 5 years (2010-2014). The following group metrics were then used to determine the publication impact and relative ranking of all 150 departments: h-index, m-index, total number of publications, sum of citations, and average number of citations per article. Ranking for each metric were also stratified by using a proxy for departmental size. The most common journals in which US and Canadian anesthesiology departments publish their work were identified. RESULTS The majority (23 of the top 25) of top-ranked anesthesiology departments are in the United States, and 2 of the top 25 departments (University of Toronto; McGill University) are in Canada. There was a strong positive relationship between each of h-index, total number of publications, and the sum of citations (0.91-0.97; P < .0001). Departmental size correlates with increased academic productivity on most metrics. The most frequent journals in which US and Canadian anesthesiology departments publish are Anesthesiology, Anesthesia and Analgesia, and the Canadian Journal of Anesthesia. CONCLUSIONS Our study ranked the Canadian and US anesthesiology departmental research productivity using the h-index applied to each department, total number of publications, total number of citations, and average number of citations. The strong relationship between the h-index and both the number of publications and number of citations of anesthesiology departments shows that the departments with the highest number of publications are also producing research with the most highly cited articles (ie, most impact), as demonstrated by the h-index.

BACKGROUND:To evaluate the relative research productivity and ranking of anesthesiology departments in Canada and the United States, using the Hirsch index (h-index) and 4 other previously validated metrics.METHODS:We identified 150 anesthesiology departments in Canada and the United States with an

OBJECTIVE:We investigated the inter-rater reliability of Web of Science (WoS) and Scopus when calculating the h-index of 25 senior scientists in the Clinical Epidemiology Program of the Ottawa Hospital Research Institute.MATERIALS AND METHODS:Bibliometric information and the h-indices for the subjects were computed by four raters using the automatic calculators in WoS and Scopus. Correlation and agreement between ratings was assessed using Spearman's correlation coefficient and a Bland-Altman plot, respectively.RESULTS:Data could not be gathered from Google Scholar due to feasibility constraints. The Spearman's rank correlation between the h-index of scientists calculated with WoS was 0.81 (95% CI 0.72-0.92) and with Scopus was 0.95 (95% CI 0.92-0.99). The Bland-Altman plot showed no significant rater bias in WoS and Scopus; however, the agreement between ratings is higher in Scopus compared to WoS.CONCLUSION:Our results showed a stronger relationship and increased agreement between raters when calculating the h-index of a scientist using Scopus compared to WoS. The higher inter-rater reliability and simple user interface used in Scopus may render it the more effective database when calculating the h-index of senior scientists in epidemiology.