Anaesthesia or sedation for MRI in children

Current Practice: Rationale for Screening Children with Hereditary Hemorrhagic Telangiectasia for Brain Vascular Malformations

BACKGROUND

Hereditary hemorrhagic telangiectasia is an autosomal dominant vascular dysplasia characterized by mucocutaneous telangiectasias, recurrent epistaxis, and organ vascular malformations including in the brain, which occur in about 10% of patients. These brain vascular malformations include high-flow AVMs and AVFs as well as low-flow capillary malformations. High-flow lesions can rupture, causing neurologic morbidity and mortality.

STATE OF PRACTICE

International guidelines for the diagnosis and management of hereditary hemorrhagic telangiectasia recommend screening children for brain vascular malformations with contrast enhanced MR imaging at hereditary hemorrhagic telangiectasia diagnosis. Screening has not been uniformly adopted by some practitioners who contend that screening is not justified. Arguments against screening include application of short-term data from the adult A Randomized Trial of Unruptured Brain Arteriovenous Malformations (ARUBA) trial of unruptured sporadic brain AVMs to children with hereditary hemorrhagic telangiectasia as well as concerns about administration of sedation or IV contrast and causing patients or families increased anxiety.

ANALYSIS

In this article, a multidisciplinary group of experts on hereditary hemorrhagic telangiectasia reviewed data that support screening guidelines and counter arguments against screening. Children with hereditary hemorrhagic telangiectasia have a preponderance of high-flow lesions including AVFs, which have the highest rupture risk. The rupture risk among children is estimated at about 0.7% per lesion per year and is additive across lesions and during a lifetime. ARUBA, an adult clinical trial of expectant medical management versus treatment of unruptured brain AVMs, favored medical management at 5 years but is not applicable to pediatric patients with hereditary hemorrhagic telangiectasia given the life expectancy of a child. Additionally, interventional, radiosurgical, and surgical techniques have improved with time. Experienced neurovascular experts can prospectively determine the best treatment for each child on the basis of local resources. The "watch and wait" approach to imaging means that children with brain vascular malformations will not be identified until a potentially life-threatening and deficit-producing intracerebral hemorrhage occurs. This expert group does not deem this to be an acceptable trade-off.

Clinical Evaluation of Oral Midazolam Containing Cyclodextrin in Pediatric Magnetic Resonance: A Retrospective Cohort Study

BACKGROUND

Reducing a child's level of anxiety before magnetic resonance imaging (MRI) procedures allows for better behavioral outcomes. The aim of this retrospective study was to evaluate anxiolytic efficacy of Midazolam/γ-cyclodextrin oral formulation.

METHODS

We retrospectively reviewed 100 medical charts of children who, between 1 February and 31 July 2022, underwent MRI under general anesthesia with or without premedication with midazolam/γ-cyclodextrin. Primary outcome was comparison of behavior to facemask positioning, while secondary endpoints were degree of drugs acceptance, anxiolytic effect evaluation, child's behavior on separation, and sevoflurane need.

RESULTS

Facemask positioning was accepted by 58% of the midazolam/γ-cyclodextrin group compared to 22% of children in the control group. The rate of acceptance was >90%. At the moment of separation from parent, none of the premedicated children needed to be restrained compared to 18% in the control group. A lower percentage of sevoflurane was needed for eye-closure at induction of anesthesia and for anesthesia maintenance. At emergence from anesthesia, 46% of children in the premedicated group compared to 66% of children in the control group showed transient agitation.

CONCLUSIONS

Midazolam/γ-cyclodextrin showed a good profile of acceptance, satisfactory anxiolytic properties, and reduced need for anesthetics when administered to children before MRI under general anesthesia.

Diagnostic accuracy of ultrasound versus X-ray for distal forearm fractures in children and adolescents: a systematic review and meta-analysis

PURPOSE

Utilizing ultrasound for the detection of distal forearm fractures in children presents a potential safe and radiation-free alternative compared to X-ray.

METHODS

A systematic review was undertaken to compare the diagnostic accuracy of ultrasound in detecting distal forearm fractures in children with X-ray imaging within the period spanning January 2010 to August 2023. The electronic databases MEDLINE and Cochrane CENTRAL were utilized for data retrieval. The QUADAS-2 tool was employed to assess the quality of the included studies. Subsequent statistical analysis was performed to calculate pooled sensitivity and specificity, positive and negative likelihood ratios, as well as the diagnostic odds ratio.

RESULTS

Our meta-analysis included seventeen studies, encompassing a total of 2003 patients, 2546 ultrasound scans, and 1203 fracture cases as identified by the reference test (X-ray). The pooled sensitivity and specificity were 0.96 (95% CI: 0.93-0.98) and 0.96 (95% CI: 0.89-0.98), respectively. The positive likelihood ratio was 13.40 (95% CI: 7.97-21.50), the negative likelihood ratio was 0.06 (95% CI: 0.04-0.1), and the pooled diagnostic odds ratio was 209 (95% CI: 92.20-412.00). Our statistical analysis revealed low heterogeneity within our studied cohort.

CONCLUSIONS

Our study indicates that ultrasound exhibits exceptionally high accuracy in the detection of distal forearm fractures in children and adolescents. It can be employed safely to either confirm or rule out a fracture, thus circumventing the need for potentially harmful radiation exposure in this vulnerable population. Future research endeavors should focus on establishing a universally accepted protocol for training and scanning methods to standardize practices and eliminate disparities in diagnostic procedures.

Retrospective comparison between MRI examinations during radiographer-administered intranasal sedation or general anesthesia

INTRODUCTION

In order for young children to be able to undergo a Magnetic Resonance Imaging (MRI) examination, general anesthesia is often required. The aim of this study was to compare the image quality, times, and costs of the examinations of infant brains performed with MRI either during sedation with dexmedetomidine administered by radiographers or anesthesia with propofol administered by anesthesia staff.

METHODS

This study was a quantitative retrospective study of 27 consecutive standard brain examinations performed under sedation or anesthesia, involving 15 children under sedation and 12 under anesthesia. The age of the children was from 0.5 to five years old. The image quality was evaluated by three radiologists experienced in pediatric MRI examinations. Information such as examination time and the expense of the examination was also collected.

RESULTS

There was no statistically significant difference in the general image quality, but one image series was assessed to have significantly better image quality under sedation than under anesthesia, but all images had very high quality. However, it emerged that children under anesthesia were at the hospital on average 55 min longer and the scanner room was occupied 20 min longer on average. The anesthesia examinations were three times more expensive.

CONCLUSION

This study demonstrated equivalent image quality between sedation and anesthesia. In addition, sedation was less time-consuming and had a lower price, partly because no extra anesthetic staff were required. The use of intranasal sedation offers a possibility to expand the competence area for radiographers.

IMPLICATIONS FOR PRACTICE

If radiographers learn to perform intranasal sedation, examinations can be performed in less time, at a third of the staff costs while maintaining image quality.

MRI scarcity in low- and middle-income countries

Since the introduction of MRI as a sustainable diagnostic modality, global accessibility to its services has revealed a wide discrepancy between populations-leaving most of the population in LMICs without access to this important imaging modality. Several factors lead to the scarcity of MRI in LMICs; for example, inadequate infrastructure and the absence of a dedicated workforce are key factors in the scarcity observed. RAD-AID has contributed to the advancement of radiology globally by collaborating with our partners to make radiology more accessible for medically underserved communities. However, progress is slow and further investment is needed to ensure improved global access to MRI.

Nonpharmacological Interventions to Reduce Sedation and General Anesthesia in Pediatric MRI: A Meta-analysis

CONTEXT

Nonpharmacological strategies are increasingly used in pediatric procedures, but in pediatric MRI, sedation and general anesthesia are still commonly required.

OBJECTIVES

To evaluate the effectiveness of nonpharmacological interventions in reducing use of sedation and general anesthesia in pediatric patients undergoing MRI, and to investigate effects on scan time, image quality, and anxiety.

DATA SOURCES

We searched Ovid Medline, CINAHL, Embase, and CENTRAL from inception through October 10, 2022.

STUDY SELECTION

We included randomized controlled trials and quasi-experimental designs comparing the effect of a nonpharmacological intervention with standard care on use of sedation or general anesthesia, scan time, image quality, or child and parental anxiety among infants (<2 years), children, and adolescents (2-18 years) undergoing MRI.

DATA EXTRACTION

Standardized instruments were used to extract data and assess study quality.

RESULTS

Forty-six studies were eligible for the systematic review. Limited to studies on children and adolescents, the meta-analysis included 20 studies with 33 873 patients. Intervention versus comparator analysis showed that nonpharmacological interventions were associated with reduced need for sedation and general anesthesia in the randomized control trials (risk ratio, 0.68; 95% confidence interval, 0.48-0.95; l2 = 35%) and nonrandomized studies (risk ratio, 0.58; 95% confidence interval, 0.51-0.66; l2 = 91%). The effect was largest among children aged 3 to 10 years when compared with older children and adolescents aged 11 to 18 years.

LIMITATIONS

There was substantial heterogeneity among nonrandomized studies.

CONCLUSIONS

Nonpharmacological interventions must be considered as standard procedure in infants, children, and adolescents undergoing MRI.

Relationship of cervical soft tissue injury and surgical predication following pediatric cervical spinal trauma and its sequelae on long-term neurologic outcome

Within the sample of 181 patients with cervical CT, CT identified unstable injury with a sensitivity of 100% and specificity of 95%. CT identified operable injury at the CCJ with 86% sensitivity and 91% specificity. CT was considered the gold standard for identification of fractures. Together, the presence of CT imaging suggestive of unstable injury or persistent neurologic complaint had a 100% sensitivity and 81% specificity. Finally, across all patients MRI had 100% sensitivity and 89% specificity for detection of unstable injury requiring surgery.

Effectiveness of training before unsedated MRI scans in young children: a randomized control trial

BACKGROUND

Young children requiring clinical magnetic resonance imaging (MRI) may be given general anesthesia. General anesthesia has potential side effects, is costly, and introduces logistical challenges. Thus, methods that allow children to undergo awake MRI scans are desirable.

OBJECTIVES

To compare the effectiveness of mock scanner training with a child life specialist, play-based training with a child life specialist, and home book and video preparation by parents to allow non-sedated clinical MRI scanning in children aged 3-7 years.

MATERIALS AND METHODS

Children (3-7 years, n=122) undergoing clinical MRI scans at the Alberta Children's Hospital were invited to participate and randomized to one of three groups: home-based preparation materials, training with a child life specialist (no mock MRI), or training in a mock MRI with a child life specialist. Training occurred a few days prior to their MRI. Self- and parent-reported functioning (PedsQL VAS) were assessed pre/post-training (for the two training groups) and pre/post-MRI. Scan success was determined by a pediatric radiologist.

RESULTS

Overall, 91% (111/122) of children successfully completed an awake MRI. There were no significant differences between the mock scanner (89%, 32/36), child life (88%, 34/39), and at-home (96%, 45/47) groups (P=0.34). Total functioning scores were similar across groups; however, the mock scanner group had significantly lower self-reported fear (F=3.2, P=0.04), parent-reported sadness (F=3.3, P=0.04), and worry (F=3.5, P=0.03) prior to MRI. Children with unsuccessful scans were younger (4.5 vs. 5.7 years, P<0.001).

CONCLUSIONS

Most young children can tolerate awake MRI scans and do not need to be routinely anesthetized. All preparation methods tested, including at-home materials, were effective.

Perioperative management and drug selection for sedated/anesthetized patients undergoing MRI examination: A review

In recent years, magnetic resonance imaging (MRI) technology has become an indispensable imaging tool owing to significant improvements in MRI that have opened up new diagnostic perspectives. Due to the closed environment, long imaging time, and need to remain still during the examination process, the examiner may cannot cooperate with the completion of the examination of the procedure, which increases the need for deep sedation or anesthesia. Achieving this can sometimes be challenging, especially in the special nontraditional environment of MRI equipment (unfamiliar and narrow spaces, away from patients, strong magnetic fields) and in special populations requiring sedation/anesthesia during examinations, which pose certain challenges for the perioperative anesthesia management of MRI. A simple "checklist" is necessary because it allows the anesthesiologist to become familiar with the particular environment and human and material resources as quickly as possible. For the choice of sedative/anesthetic, the traditional drugs, such as midazolam and ketamine, are still used due to the ease of administration despite their low sedation success rate, prolonged recovery, and significant adverse events. Currently, dexmedetomidine, with respiratory drive preservation, propofol, with high effectiveness and rapid recovery, and sevoflurane, which is mild and nonirritating, are preferred for sedation/anesthesia in children and adults undergoing MRI. Therefore, familiarity with the perioperative management of patient sedation and general anesthesia and drug selection in the MRI environment is critical for successful surgical completion and for the safe and rapid discharge of MRI patients receiving sedation/anesthesia.

Comparing Characteristics and Treatment of Brain Vascular Malformations in Children and Adults with HHT

Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant disease characterized by the development of vascular malformations (VMs) in organs such as the brain and lungs, as well as telangiectases on mucosal surfaces. Prophylactic treatment of organ VMs may prevent potential complications, such as hemorrhage. However, brain VM treatment-surgical resection, embolization, and/or radiosurgery-is not recommended for all patients due to the associated risks. Given the scarcity of data regarding HHT-related brain VM presentation and treatment trends in pediatric patients, we aim to describe the clinical presentations and the patterns of treatment of HHT-related brain VMs in a pediatric cohort, and compare pediatric trends to those of adults. Demographic and clinical data were analyzed in 114 pediatric patients with HHT-related brain VMs and compared with a cohort of 253 adult patients enrolled in the multicenter Brain Vascular Malformation Consortium HHT Project. Our data demonstrated that a higher proportion of pediatric patients with HHT-related brain VMs were symptomatic at presentation (p = 0.004). Moreover, a higher proportion of pediatric patients presented with intracranial hemorrhage (p < 0.001) and seizure (p = 0.002) compared to adult patients. Surgical resection was the most common brain VM treatment modality in both children and adults. We conclude that pediatric patients may be more likely to present with symptoms and complications from brain VMs, supporting the case for screening for brain VMs in children with HHT.

The MotoNet: A 3 Tesla MRI-Conditional EEG Net with Embedded Motion Sensors

We introduce a new electroencephalogram (EEG) net, which will allow clinicians to monitor EEG while tracking head motion. Motion during MRI limits patient scans, especially of children with epilepsy. EEG is also severely affected by motion-induced noise, predominantly ballistocardiogram (BCG) noise due to the heartbeat.

METHODS

The MotoNet was built using polymer thick film (PTF) EEG leads and motion sensors on opposite sides in the same flex circuit. EEG/motion measurements were made with a standard commercial EEG acquisition system in a 3 Tesla (T) MRI. A Kalman filtering-based BCG correction tool was used to clean the EEG in healthy volunteers.

RESULTS

MRI safety studies in 3 T confirmed the maximum heating below 1 °C. Using an MRI sequence with spatial localization gradients only, the position of the head was linearly correlated with the average motion sensor output. Kalman filtering was shown to reduce the BCG noise and recover artifact-clean EEG.

CONCLUSIONS

The MotoNet is an innovative EEG net design that co-locates 32 EEG electrodes with 32 motion sensors to improve both EEG and MRI signal quality. In combination with custom gradients, the position of the net can, in principle, be determined. In addition, the motion sensors can help reduce BCG noise.

Correlation between three-dimensional echocardiography and cardiopulmonary fitness in patients with univentricular heart: A cross-sectional multicentre prospective study

BACKGROUND

The prognosis of patients with a functional single ventricle has improved, with better cardiopulmonary fitness, health-related quality of life and survival. Conventional echocardiography remains the first-line technique in single ventricle follow-up. Three-dimensional (3D) echocardiography has shown recent value in congenital cardiology, but its ability to predict functional status in patients with a single ventricle remains unknown.

AIM

To evaluate, in patients with a single ventricle, the association between 3D echocardiography variables and functional status determined by cardiopulmonary fitness.

METHODS

Children and adults with a functional single ventricle were prospectively enrolled in this multicentre study. Cardiopulmonary fitness was assessed by cardiopulmonary exercise test, with measures of maximum oxygen uptake (VO_2max) and ventilatory efficiency (VE/VCO₂ slope). 3D echocardiography was performed with off-line reproducibility analyses, using TomTec Arena™ software. Health-related quality of life was assessed using the SF-36 questionnaire.

RESULTS

A total of 33 patients were screened, and 3D echocardiography analyses were feasible in 22 subjects (mean age 28±9years). 3D echocardiography ejection fraction correlated with percent-predicted VO_2max (r=0.64, P<0.01), VE/VCO₂ slope (r=-0.41, P=0.05), two-dimensional echocardiography ejection fraction (r=0.55, P<0.01) and health-related quality of life physical functioning dimension (r=0.56, P=0.04). 3D echocardiography indexed end-systolic volume correlated with percent-predicted VO_2max (r=-0.45, P=0.03) and VE/VCO₂ slope (r=0.65, P<0.01). 3D echocardiography reproducibility was good.

CONCLUSIONS

Single ventricle ejection fraction and volumes measured by 3D echocardiography correlated with cardiopulmonary fitness, as determined by two main prognostic cardiopulmonary exercise test variables: VO_2max and VE/VCO₂ slope. Despite good reproducibility, 3D echocardiography feasibility remained limited. 3D echocardiography may be of value in single ventricle follow-up, provided that the technique and analysis software are improved.

Initial Evidence for Positive Effects of a Psychological Preparation Program for MRI "iMReady" in Children with Neurofibromatosis Type I and Brain Tumors-How to Meet the Patients' Needs Best

To provide an effective alternative to sedation during MRI examinations in pediatric cancer and NF1 patients, the aims of the present study were to (1) exploratively evaluate a behavioral MRI training program, to (2) investigate potential moderators, as well as to (3) assess the patients' well-being over the course of the intervention. A total of n = 87 patients of the neuro-oncology unit (mean age: 6.83 years) underwent a two-step MRI preparation program, including training inside the scanner, and were recorded using a process-oriented screening. In addition to the retrospective analysis of all data, a subset of 17 patients were also analyzed prospectively. Overall, 80% of the children receiving MRI preparation underwent the MRI scan without sedation, making the success rate almost five times higher than that of a group of 18 children that opted out of the training program. Memory, attentional difficulties, and hyperactivity were significant neuropsychological moderators for successful scanning. The training was associated with favorable psychological well-being. These findings suggest that our MRI preparation could present an alternative to sedation of young patients undergoing MRI examinations as well as a promising tool for improving patients' treatment-related well-being.

COMPARISON OF INTRAMUSCULAR VERSUS INTRAVENOUS KETAMINE FOR SEDATION IN CHILDREN UNDERGOING MAGNETIC RESONANCE IMAGING EXAMINATION

OBJECTIVE

The aim: To compare efficacy of intramuscular (IM) versus intravenous (IV) ketamine for sedation in children undergoing brain MRI scanning in children.

PATIENTS AND METHODS

Materials and methods: Children who required elective brain MRI were selected for this study. They were randomly divided into two groups; group I received 1.5 mg/kg IV Ketamine and group II received 4 mg/kg IM ketamine. In each group supplementary 0.1 mg/kg midazolam intravenously before positioning on MRI table was given. Patients were monitored for pulse rate, SPO2, and respiratory wave.

RESULTS

Results: Children who received IM ketamine had significantly shorter scan time and a greater success rate of sedation with first dose than the IV group. The proportions of scan interruption and scan repeat were significantly higher among the IV group than in the IM group. The scan time was longer among the IV group than in the IM group with significantly more scan interruption and repeat. Satisfaction with sedation as expressed by the technicians was significantly more in the IM group than in IV group (98.1% vs. 80.8%, P= 0.004).

CONCLUSION

Conclusions: Intramuscular ketamine injection was predicted to have a better sedative success rate and takes less time to complete than intravenous admin¬istration. This makes IM ketamine more appealing in certain conditions.

Comparison of single-shot nebuliser protocol between dexmedetomidine and ketamine in children undergoing magnetic resonance imaging

BACKGROUND

Sedation for magnetic resonance imaging mandates deep sedation to ensure patient immobility. The nebulised route of drug delivery carries the advantage of good bioavailability and safety profile. We aimed to compare the efficacy and safety of nebulised dexmedetomidine and ketamine for sedation in children undergoing magnetic resonance imaging.

METHODS

A total of 71 children, aged two to eight years scheduled for outpatient magnetic resonance imaging were randomly allocated to receive nebulised dexmedetomidine 2 μg/kg (group D) or nebulised ketamine 2 mg/kg (group K) 30min before magnetic resonance imaging.

RESULTS

Nebulised dexmedetomidine (2 μg/kg) resulted in faster onset and significantly better sedation scores with rapid clear-headed recovery. Ketamine resulted in better venepuncture scores but was associated with more neuropsychological events at recovery.

CONCLUSION

Nebulised dexmedetomidine at 2 μg/kg provides rapid onset of satisfactory sedation, with good parental separation and a quicker and more clear-headed recovery, allowing for a smooth magnetic resonance imaging experience.

Development of a Super-Resolution Scheme for Pediatric Magnetic Resonance Brain Imaging Through Convolutional Neural Networks

Pediatric medical imaging represents a real challenge for physicians, as children who are patients often move during the examination, and it causes the appearance of different artifacts in the images. Thus, it is not possible to obtain good quality images for this target population limiting the possibility of evaluation and diagnosis in certain pathological conditions. Specifically, magnetic resonance imaging (MRI) is a technique that requires long acquisition times and, therefore, demands the use of sedation or general anesthesia to avoid the movement of the patient, which is really damaging in this specific population. Because ALARA (as low as reasonably achievable) principles should be considered for all imaging studies, one of the most important reasons for establishing novel MRI imaging protocols is to avoid the harmful effects of anesthesia/sedation. In this context, ground-breaking concepts and novel technologies, such as artificial intelligence, can help to find a solution to these challenges while helping in the search for underlying disease mechanisms. The use of new MRI protocols and new image acquisition and/or pre-processing techniques can aid in the development of neuroimaging studies for children evaluation, and their translation to pediatric populations. In this paper, a novel super-resolution method based on a convolutional neural network (CNN) in two and three dimensions to automatically increase the resolution of pediatric brain MRI acquired in a reduced time scheme is proposed. Low resolution images have been generated from an original high resolution dataset and used as the input of the CNN, while several scaling factors have been assessed separately. Apart from a healthy dataset, we also tested our model with pathological pediatric MRI, and it successfully recovers the original image quality in both visual and quantitative ways, even for available examples of dysplasia lesions. We hope then to establish the basis for developing an innovative free-sedation protocol in pediatric anatomical MRI acquisition.

Children and neonates anesthesia in magnetic resonance environment in Italy: an active call survey

Background

Pediatric anesthesia care in the Magnetic Resonance Imaging is a challenge for clinicians. The recent debate about the role of anesthetic agent on neural development, encouraged an evaluation of their actual activity in this environment. In this active call survey, the authors sought to delineate the Italian situation regarding national centers, staff involved, monitoring tools available and sedation techniques.

Methods

A complete sample of all national centers performing almost a pediatric discharge in the 2014 was obtained from Health Ministry registers. All Institutions were contacted for a prospective phone investigation and a three-section survey was fill out with the Physician in charge. A descriptive and exploratory analyzes about the organization setting of the Centers were performed.

Results

Among 876 Institution screened, only 106 (37%) met minimal criteria for inclusion. Children are managed by anesthesiologists in the 95% of cases, while neonates in the 54%. A dedicated nurse is present in 74% of centers. While a pulse oximetry is present in 100% of centers, the rate of prevalence of other monitoring is lower. A specific MRI-compatible ventilator is available in the 95% of Centers, but many tools are not equally homogenously distributed. Pharmacological approach is preferred in pediatric age (98%), but its use for newborns is reduced to 43%.

Conclusions

We found significant heterogeneity in the daily clinical practice of sedation in MRI. Our results could be a starting point to evaluate the further evolution of approach to children and neonates in magnetic resonance setting.

Trial registration

ClinicalTrials.gov identifier: NCT04775641.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-022-01821-3.

Temperature change in children undergoing magnetic resonance imaging-An observational cohort study

AIM

An increasing number of children undergo magnetic resonance imaging requiring anesthesia or sedation to ensure their immobility; however, magnetic resonance imaging may increase body temperature whereas sedation or anesthesia may decrease it. We investigated changes in body temperature in children who underwent sedation or anesthesia for magnetic resonance imaging.

METHODS

Children aged 12 weeks-12 years undergoing anesthesia and magnetic resonance imaging were included in this prospective observational study. Tympanic body temperature was measured before and after magnetic resonance imaging, and the difference between measurements was calculated. Associations between the temperature difference and patient- or procedure-related factors were evaluated with linear and logistic regression analysis.

RESULTS

A total of 74 children were included, of whom 5 (7%) had a temperature increase ≥0.5°C. Mean temperature difference was -0.24°C (SD 0.48) for the entire group and -0.28°C for the youngest children (0-2 years). The temperature difference correlated positively with the duration of imaging (unadjusted coefficient 0.26, 95% confidence interval (CI), (0.01; 0.52)).

CONCLUSION

In this study of sedated or anesthetized children undergoing magnetic resonance imaging, clinically relevant increases in body temperature above 0.5°C were only found in a few patients. However, longer imaging duration tended to be associated with increased body temperature.

Free-breathing magnetic resonance imaging with radial k-space sampling for neonates and infants to reduce anesthesia

BACKGROUND

Conventional chest and abdominal MRI require breath-holds to reduce motion artifacts. Neonates and infants require general anesthesia with intubation to enable breath-held acquisitions.

OBJECTIVE

We aimed to validate a free-breathing approach to reduce general anesthesia using a motion-insensitive radial acquisition with respiratory gating.

MATERIALS AND METHODS

We retrospectively enrolled children <3 years old who were referred for MRI of the chest or abdomen. They were divided into two groups according to MRI protocol: (1) breath-held scans under general anesthesia with T2-weighted single-shot fast spin-echo (SSFSE) and contrast-enhanced T1-weighted modified Dixon, and (2) free-breathing scans using radial sequences (T2-W MultiVane XD and contrast-enhanced T1-W three-dimensional [3-D] Vane XD). Two readers graded image quality and motion artifacts.

RESULTS

We included 23 studies in the free-breathing cohort and 22 in the breath-hold cohort. The overall imaging scores for the free-breathing radial T2-W sequence were similar to the scores for the breath-held T2-W SSFSE sequence (chest, 3.6 vs. 3.2, P=0.07; abdomen, 3.9 vs. 3.7, P=0.66). The free-breathing 3-D radial T1-W sequence also had image quality scores that were similar to the breath-held T1-W sequence (chest, 4.0 vs. 3.0, P=0.06; abdomen, 3.7 vs. 3.9, P=0.15). Increased motion was seen in the abdomen on the radial T2-W sequence (P<0.001), but increased motion was not different in the chest (P=0.73) or in contrast-enhanced T1-W sequences (chest, P=0.39; abdomen, P=0.15). The mean total sequence time was longer in free-breathing compared to breath-held exams (P<0.01); however, this did not translate to longer overall exam times (P=0.94).

CONCLUSION

Motion-insensitive radial sequences used for infants and neonates were of similar image quality to breath-held sequences and had decreased sedation and intubation.

Dexmedetomidine sedation vs. inhaled general anesthesia for pediatric MRI: A retrospective cohort study: Dexmedetomidine sedation vs. inhaled general anesthesia for MRI

OBJECTIVES

The objective of this study was to evaluate the feasibility and the efficacy of a dexmedetomidine-based protocol followed by anesthesiologists unaccustomed to using dexmedetomidine during pediatric magnetic resonance imaging (MRI) examinations compared to conventional halogenated general anesthesia.

METHODS

This was a single-center retrospective cohort study including patients younger than 18 years who underwent sedation for MRI between August 1, 2018 and March 31, 2019. Patients who received dexmedetomidine were included in the DEX group and patients who had general anesthesia formed the GA group. Patients were matched with a ratio of 2 GA:1 DEX, based on age and type of MRI examination.

RESULTS

Overall, 78 patients were included (DEX=26; GA=52). Dexmedetomidine was significantly associated with a decrease in invasive ventilation (p<0.001) with no impact on image quality. The sedation failure rate was 42% with dexmedetomidine vs. 0% with general anesthesia (p<0.001). All cases of failure followed the intranasal administration of dexmedetomidine.

CONCLUSION

Dexmedetomidine seems to be a suitable sedation option for pediatric MRI. It provides an alternative to halogenated general anesthesia with the aim of limiting exposure to conventional anesthetic agents and invasive ventilation.

Effectiveness of Chloral Hydrate on Brain MRI in Children with Developmental Delay/Intellectual Disability Comparing with Normal Intelligence: Single Tertiary Center Experience

Neurodiagnostic investigation requirements are expanding for diagnostic and therapeutic purposes in children, especially in those with developmental delay/intellectual disability (DD/ID). Thus, determination of optimal sedatives to achieve successful sedation and immobility without further neurological compromise is important in children with DD/ID. The purpose of this study is to assess the effectiveness and adverse reactions of chloral hydrate (CH) for brain magnetic resonance imaging (B-MRI) in children with DD/ID compared to those with normal intelligence (NI). We performed a retrospective chart review of children aged from 1 day to 12 years who required elective sedation using CH for B-MRI. About 730 cases (415 with DD/ID and 315 with NI) of CH sedation were conducted for B-MRI. Children with DD/ID showed a higher failure rate (22%) than did those with NI (6%); additional CH and prolonged sedation time were required. There was no difference in incidence of adverse reactions between DD/ID and NI groups (p = 0.338). Older or heavier children with DD/ID (p = 0.036 and p = 0.013, respectively), as well as those diagnosed with epilepsy or neuropsychiatric disorders showed higher risk of sedation failure (p < 0.001 for each). In conclusion, CH was a suboptimal sedative drug for children with DD/ID compared with those with NI. Other alternative or supplementary sedatives should be taken into consideration especially for those vulnerable groups.

The optimal dose of oral midazolam with or without intranasal S-ketamine for premedication in children: a randomised, double blinded, sequential dose-finding trial

BACKGROUND

Oral administration of midazolam syrup is one of the most favorable methods of premedication, the optimal dose of midazolam and midazolam with S-ketamine for preschool children has not been determined. This prospective, double-blind, randomized, sequential dose-finding study was designed to estimate the 90% effective doses of oral midazolam with and without intranasal S-ketamine in a grade III child medical center.

METHODS

Eighty successive children were recruited and randomly allocated to midazolam group and midazolam with S-ketamine group. The initial oral doses of midazolam were 0.25 mg/kg in both groups, and the dose of midazolam for the next child was based on the response of the preceding child as the biased coin up-and-down designed. The primary outcome was parental separation anxiety score = 1 throughout the period of transferring from premedication center to the operation room 30 min after premedication. Secondary outcomes were the preoperative and post-operative observations. Finally, the 90% effective dose and 95% confidence intervals were estimated by isotonic regression.

RESULTS

The 90% effective dose of oral midazolam or oral midazolam with intranasal S-ketamine was 0.461 mg/kg (95% confidence interval: 0.425-0.488) and 0.253 mg/kg (95% confidence interval: 0.242-0.278), respectively. Oral midazolam with intranasal S-ketamine was quicker onset (8.9±3.8 vs. 19.7±7.4 min, P<0.001), had less incidence of behavioral changes (7.5% vs. 32.5%, P=0.010) and faster recovery (21.6±14.1 vs. 31.6±13.5 min, P=0.002) than solely oral midazolam.

CONCLUSIONS

A suggestion of oral midazolam 0.3 mg/kg with intranasal small dose of S-ketamine could be used as premedication for preschool children.

TRIAL REGISTRATION

Chinese Clinical Trial Registry.

The frequency of emergence delirium in children undergoing outpatient anaesthesia for magnetic resonance imaging

AIM

The aim of this study was to investigate the effect on the occurrence of emergence delirium of propofol and ketofol with intranasal dexmedetomidine and midazolam applied as premedication to paediatric patients during magnetic resonance imaging (MRI).

METHODS

The study included children aged 2-10 years who received sedation for MRI, separated into four groups. Group MP (midazolam-propofol) received intranasal midazolam (0.2 mg/kg) for premedication and intravenous (IV) propofol (1 mg/kg) as the anaesthetic agent. Group MK (midazolam-ketofol) received intranasal midazolam (0.2 mg/kg) for premedication and IV ketofol (1 mg/kg) as the anaesthetic agent. Group DP (dexmedetomidine-propofol) received intranasal dexmedetomidine (1 mcg/kg) for premedication and IV propofol (1 mg/kg) as the anaesthetic agent. Group DK (dexmedetomidine-ketofol) received intranasal dexmedetomidine (1 mcg/kg) for premedication and IV ketofol (1 mg/kg) as the anaesthetic agent. The Paediatric Anaesthesia Emergence Delirium (PAED) scale was used to evaluate delirium. A PAED score ≥ 10 was accepted as delirium.

RESULTS

Statistical analysis was made of 140 paediatric patients. Delirium developed in 1.42% of all the patients, and in 5.7% of Group MP. The mean Aldrete and PAED scores were lower and the length of stay in the recovery room was shorter in Group DP than in the other groups. The need for additional anaesthetic was highest in Group DP at 94.3% and lowest in Group DK at 14.3%. The groups administered ketofol were observed to have a lower requirement for additional anaesthetic.

CONCLUSION

Delirium was seen at a very low rate only in the Group MP and it is difficult to say the best combination in terms of delirium frequency. However, intranasal dexmedetomidine and IV ketofol seem to be better and safer than the other groups in terms of the need for additional doses and the number of side effects. The addition of ketamine to propofol reduces the need for additional doses with a synergistic effect.

Lower-Dose Propofol Use for MRI: A Retrospective Review of a Pediatric Sedation Team's Experience

OBJECTIVE

The aim of the study was to evaluate, in children undergoing procedural sedation for magnetic resonance imaging (MRI) scans, whether lower doses of propofol than previously published permitted a high rate of successful MRI completion, whether lower dosages result in a more rapid recovery, and whether age or behavioral diagnosis increases propofol requirements.

METHODS

After institutional review board approval, we retrospectively reviewed the pediatric sedation team's sedation database of children receiving propofol infusion for MRI scans between 2007 and 2016. Data collected included propofol induction dose (in milligrams per kilogram), propofol infusion dose (in micrograms per kilogram per hour), total propofol dose (in milligrams per kilogram and in milligrams per kilogram per hour), and the number of administered ancillary sedative medications. Additional data included the American Society of Anesthesiologist status, sedation duration, recovery duration, and successful completion of MRI. Dosing data were also stratified by age.

RESULTS

A total of 2354 patients met inclusion criteria. Eight percent of patients received propofol infusion alone, 79% received midazolam before their propofol induction, and 13% received a combination of propofol and other drugs. Mean induction dose was 2.2 + 0.9 mg/kg, mean infusion dose was 93.5 + 29.0 μg/kg per minute, and total mean dose was 9.0 + 3.0 mg/kg per hour. Mean recovery time was 44 minutes, and 99.3% of the scans were completed with good images. We noted an increase requirement in the mean induction dose and total dose in children younger than 1 year.

CONCLUSIONS

Propofol infusion doses lower than commonly reported permit successful completion of scans and similar recovery times in a single institution. Younger children require more propofol for successful procedural sedation.

Nonpharmacological interventions to reduce sedation/general anaesthesia in paediatric patients undergoing magnetic resonance imaging: A systematic review and meta-analysis protocol

BACKGROUND

Magnetic resonance imaging is frequently used in paediatrics and requires the child/adolescent to remain still for 45 min or more. The long and narrow scanner gantry makes loud noises and may cause anxiety. To complete the procedure, children and adolescents are often sedated or receive general anaesthesia. Our primary aim is to determine whether nonpharmacological interventions designed to mentally prepare, support or distract children, and adolescents are effective in reducing the need for sedation and general anaesthesia.

METHODS

We will conduct a systematic review with meta-analysis by searching the following electronic databases: Ovid MEDLINE, CINAHL, Embase and CENTRAL, as well as databases for ongoing trials. Eligibility criteria are based on the participants, intervention, comparator and outcome (PICO) framework. We will include intervention studies with comparator group(s) with no restriction on date. Two reviewers will independently screen titles/abstracts, and three reviewers will assess the full texts of potentially relevant studies. Data will be extracted, and the methodological quality will be assessed using Cochrane risk of bias tools. If the data allow, we will perform a meta-analysis using a random effects model on the primary outcome, sedation/general anaesthesia. A narrative synthesis will supplement the statistical analysis. Quality of evidence for the primary outcome will be assessed using the grading of recommendations, assessment, development and evaluations (GRADE) approach.

DISCUSSION

Our findings will provide directions for future research and may guide clinicians in terms of which type(s) of intervention(s) to implement to reduce the use of sedation/general anaesthesia during paediatric magnetic resonance imaging.

Magnetic Resonance Imaging under Sedation in Pediatric Patients: A Single-Institution Experience

Magnetic resonance imaging (MRI) scans for children are a challenge for anesthesiologists since the child must be sedated enough to stand still. But anesthetic drugs used for sedation might have serious side effects and monitorization resources and accessibility to the patient during MRI scan is limited. We retrospectively examined 977 pediatric patients' files who had MRI scans in our hospital. We observed that children received one of the four combinations of anesthetic drugs: group 1 received midazolam, propofol, and ketamine; group 2 received midazolam and ketamine; group 3 received midazolam and thiopental; and group 4 received midazolam and propofol combination for sedation. The patients in group 1 had significantly higher vomiting rates than the patients in group 4 (p = 0.005). We observed bronchospasm in patients in group 1 (p = 0.006) and group 3 (p = 0.001), more than in patients in group 4. Nausea and vomiting ratios were lower in group 4. In patients with nausea and vomiting within a week after the procedure, statistically significant lower neutrophil–lymphocyte ratio values (p = 0.012) were observed. All four anesthetic combinations used in the trial provided safe anesthesia for the children, during the MRI scan. The anesthetic choice must be made according to the procedure time and patient's comorbidities. In this trial, we observed minimum side effects with midazolam and propofol combination.

Comparison of Low-Dose Sevoflurane Inhalation With Intranasal Ketamine as Rescue Sedation After Intranasal Dexmedetomidine Failure in Outpatient Children Undergoing MRI: A Randomized Control Trial

PURPOSE

The present study aimed to evaluate the effectiveness and safety of low-dose inhalation of sevoflurane through a face mask as a rescue remedy for sedation compared with intranasal ketamine in outpatient children undergoing magnetic resonance imaging (MRI).

DESIGN

A prospective randomized control study. A total of 336 children scheduled for 3.0T MRI but were inadequately sedated after initial intranasal dexmedetomidine (3 μg/kg) were randomly divided into two groups.

METHODS

We used the following protocol for each group: group S, inhalation of low-dose sevoflurane (end-expiratory concentration, 0.4%) through a face mask; group K, intranasal ketamine (2 mg/kg). The success rates were compared between groups as the primary endpoint. The induction time, scan time, recovery time, time to return to baseline functional status, parental and radiologist satisfaction, occurrence of adverse events, and other secondary endpoints were also compared.

FINDINGS

Successful rescue sedation in groups S and K was achieved in 160 (95.2%) and 138 (82.1%) patients, respectively. Compared with group K, group S needed fewer repeat sequences and showed a significantly shorter induction time (5.7 ± 0.5 vs. 10.9 ± 2.7 min; P < 0.001), recovery time (27.4 ± 6.3 vs. 53.8 ± 15.2 min; P < 0.001), and time to return to baseline functional status (3.4 ± 0.6 vs. 6.1 ± 1.1 h; P < 0.001). Radiologist satisfaction, parental satisfaction, and parental desire to repeat the same sedation method were significantly higher in the sevoflurane group.

CONCLUSION

Our results suggest that the inhalation of low-dose sevoflurane through a face mask can provide effective and safe rescue sedation in 1- to 6-year-old outpatient children undergoing MRI, and yields a higher success rate, shorter induction and recovery times, and higher satisfaction than the intranasal ketamine method.

Utility of contrast-enhanced ultrasound for solid mass surveillance and characterization in children with tuberous sclerosis complex: an initial experience

BACKGROUND

Patients with tuberous sclerosis complex (TSC) can develop solid kidney masses from childhood. Imaging surveillance is done to detect renal cell carcinoma (RCC) and angiomyolipomas (AML), including AMLs at risk for hemorrhage. Intravenous contrast-enhanced ultrasound (CEUS) may be useful for screening as ultrasound is well tolerated by children and ultrasound contrast agents (UCA) are not nephrotoxic.

METHODS

Retrospective review of kidney CEUS exams of pediatric TSC patients. Qualitative CEUS analysis by consensus of 3 radiologists assessed rate, intensity, and pattern of lesion enhancement. Quantitative CEUS analysis was performed using Vuebox®. Where available, abdominal MRI was analyzed qualitatively for the same features and quantitatively by in-house-developed software. Time-intensity curves were generated from both CEUS and MRI where possible. Appearance of lesions were compared between CEUS and MRI and histology where available.

RESULTS

Nine masses in 5 patients included one histologically proven RCC and 8 AMLs diagnosed by imaging. Quantitative CEUS of RCC showed malignant features including increased peak enhancement 162%, rapid wash-in rate 162%, and elevated washout rate 156% compared to normal kidney tissue; versus AML which was 68%, 105%, and 125%, respectively. All masses were hypoenhancing on MRI compared to normal kidney tissue; MR dynamic contrast study offered no distinction between RCC and AML. The only MRI feature differentiating RCC from AML was absence of fat.

CONCLUSION

Temporal resolution afforded by CEUS was useful to distinguish malignant from benign kidney masses. CEUS may prove useful for screening, characterizing, and follow-up of kidney lesions in pediatric TSC patients.

Effects of dexmedetomidine sedation for magnetic resonance imaging in children: a systematic review and meta-analysis

PURPOSE

Pediatric sedation is commonly required to obtain high-quality images in magnetic resonance imaging (MRI). We performed a systematic review and meta-analysis to assess the effects of dexmedetomidine sedation for MRI in children.

METHODS

A systematic review was conducted to find all randomized controlled trials concerning dexmedetomidine sedation for MRI in children. We searched databases using the Ovid platform in the Cochrane Controlled Trials Register, MEDLINE, and EMBASE. This study was registered in the PROSPERO database: CRD42020198368.

RESULTS

Seven studies and 753 participants were included. Dexmedetomidine sedation showed a significantly delayed onset time [weighted mean differences (WMD) = 8.13 min, 95% confidence interval (CI) 4.64 to 11.63, I² = 98%] and recovery time (WMD = 5.22 min, 95% CI 0.35 to 10.09, I² = 92%) compared to propofol, ketamine, and midazolam sedation. There was no difference in quality of sedation [risk ratio (RR) = 1.25, 95% CI 0.92 to 1.69, I² = 89%], or incidence of sedation failure (RR = 1.39, 95% CI 0.53 to 3.66, I² = 83%) between groups. Although a significantly decreased heart rate (WMD = - 17.34 beats/minute, 95% CI - 22.42 to - 12.26, I² = 96%) was observed, bradycardia that required treatment was not increased (RR = 8.00, 95% CI 1.02 to 62.64, I² = 0%). Dexmedetomidine sedation had a lower incidence of desaturation events (RR = 0.42, 95% CI 0.20 to 0.86, I² = 4%). However, there was no difference in incidence of postoperative vomiting (RR = 0.42, 95% CI 0.15 to 1.17, I² = 17%) between groups.

CONCLUSIONS

Dexmedetomidine sedation provided a similar sedation quality with a reduced incidence of desaturation events. However, the delayed onset and recovery times were drawbacks. The clinical significance of bradycardia is considered to be low. GRADE assessment revealed the quality of the evidence in this meta-analysis ranged from very low to moderate.

Pediatric characteristics and the dose of propofol for sedation during radiological examinations: a retrospective analysis

OBJECTIVE

The present study aimed to investigate patients' characteristics that can affect the dose of propofol required to sedate children undergoing imaging.

METHODS

In this retrospective, observational study, we reviewed medical records of children aged 0 to 18 years who were classified as having American Society of Anesthesiologists status 1 or 2 and they underwent imaging under propofol sedation between January 2011 and August 2016. Collected data included patients' demographics, propofol doses, duration of sedation, and complications. Regression analysis was performed to determine patients' characteristics that may affect the dose of propofol required to induce sedation.

RESULTS

A total of 925 patients were included. Simple linear regression showed that the dose of propofol was correlated with age, height, weight, and body surface area. Using the results of multiple linear regression, the following formula was used to estimate the dose of propofol (mg) for sedation: 0.75 + 0.14 × age (months) + 45.82 × body surface area (m²).

CONCLUSION

A child's age, height, and body surface area should be considered when deciding the induction dose of propofol. Additionally, the formula that we have proposed can be used to estimate the dose of propofol required to induce sedation in children undergoing imaging.

Editorial Commentary: The Pediatric Knee: Ultrasound Could Replace Magnetic Resonance Imaging for Evaluating a Discoid Lateral Meniscus

Magnetic resonance imaging has been referred to as the gold standard diagnostic modality for meniscal pathology in the adult knee. However, there are multiple issues with reliance on magnetic resonance imaging for evaluating the meniscus in children. Diagnostic accuracy for meniscus pathology in children is not as high as with adults. Additionally, young children often cannot tolerate lying still for the study and require sedation, with a small but non-zero risk of anesthetic complication and risk motion artifact even with sedation. Ultrasound can be used to reliably diagnose a discoid lateral meniscus in a testing environment that is well tolerated by young children.

Improving Care and Outcomes for Pediatric Musculoskeletal Infections

BACKGROUND

Pediatric musculoskeletal infection (MSKI) is a common cause of hospitalization with associated morbidity. To improve the care of pediatric MSKI, our objectives were to achieve 3 specific aims within 24 months of our quality improvement (QI) interventions: (1) 50% reduction in peripherally inserted central catheter (PICC) use, (2) 25% reduction in sedations per patient, and (3) 50% reduction in empirical vancomycin administration.

METHODS

We implemented 4 prospective QI interventions at our tertiary children's hospital: (1) provider education, (2) centralization of admission location, (3) coordination of radiology-orthopedic communication, and (4) implementation of an MSKI infection algorithm and order set. We included patients 6 months to 18 years of age with acute osteomyelitis, septic arthritis, or pyomyositis and excluded patients with complex chronic conditions or ICU admission. We used statistical process control charts to analyze outcomes over 2 general periods: baseline (January 2015-October 17, 2016) and implementation (October 18, 2016-April 2019).

RESULTS

In total, 224 patients were included. The mean age was 6.1 years, and there were no substantive demographic or clinical differences between baseline and implementation groups. There was an 81% relative reduction in PICC use (centerline shift 54%-11%; 95% confidence interval 70-92) and 33% relative reduction in sedations per patient (centerline shift 1.8-1.2; 95% confidence interval 21-46). Empirical vancomycin use did not change (centerline 20%).

CONCLUSIONS

Our multidisciplinary MSKI QI interventions were associated with a significant decrease in the use of PICCs and sedations per patient but not empirical vancomycin administration.

Brain MRI without anesthesia in children less than 3 months old

INTRODUCTION

The use of general anesthesia in infants involves both short-term and long-term risks. The aim of this study is to evaluate the efficacy of brain MRI without anesthesia in infants younger than 3-month-old immobilized with a pillow.

PATIENTS AND METHODS

This prospective case-control study was done in 2019. Cases were stable patients less than 3 months old who did not require ventilatory support for whom brain MRI was indicated. Patients were fed so they would fall asleep and placed in the scanner with an immobilizing pillow. Controls were clinically unstable patients matched for age and sex referred for brain MRI under general anesthesia. Three pediatric radiologists evaluated the success of the MRI study (whether it answered the clinical question), recorded whether it was necessary to repeat the study, and rated the presence of motion artifacts on a scale ranging from 1 to 4.

RESULTS

A total of 47 cases were included (28 boys and 19 girls; mean age, 31 days). Of these, 42 (89%) MRI studies were considered successful. The proportion of successful MRI studies was lower in outpatients than in inpatients (p=0.02). The quality of MRI in cases was considered optimal in 60% and suboptimal (motion artifacts in one or two sequences) in 30%. No safety issues related with the technique were detected. The mean duration of the studies was 16.6minutes (range, 6-30minutes). All of the MRI studies in controls were considered successful; quality was considered optimal in 89% and suboptimal in 11%. In the first year in which we used this technique, we avoided the use of general anesthesia in 47 MRI studies in 42 newborns.

CONCLUSION

Brain MRI using the feed and sleep technique in infants younger than 3-month-old immobilized with a pillow can be done safely and efficaciously without general anesthesia.

Diagnosing and treating native spinal and pelvic osteomyelitis in adolescents

STUDY DESIGN

Retrospective case series.

OBJECTIVES

To describe how pediatric patients with spinal and pelvic osteomyelitis are diagnosed and treated and assess the diagnostic value of magnetic resonance imaging (MRI), needle aspiration biopsy (NAB), and blood cultures in this population. Spinal and pelvic osteomyelitis de novo are uncommon in children and minimal literature exists on the subject. Research has shown that NAB and blood cultures have variable diagnostic yield in adult native osteomyelitis. At our institution, there is no standard protocol for diagnosing and treating pediatric spinal and pelvic osteomyelitis de novo.

METHODS

All diagnoses of spinal and pelvic osteomyelitis at a pediatric tertiary care center from 2003 to 2017 were reviewed. Patients aged 0-21 at diagnosis were included. Patients with osteomyelitis resulting from prior spinal operations, wounds, or infections and those with chronic recurrent multifocal osteomyelitis were eliminated. All eligible patients' diagnoses were confirmed by MRI.

RESULTS

29 patients (18 men, 11 women) met the inclusion criteria. The median age at diagnosis was 11 years old (range 1-18). More than half of all cases (17/29, 59%) affected the lumbar spine. The most common symptoms were back pain (20/29, 69%), fever (18/29, 62%), hip pain (11/29, 38%), and leg pain (8/29, 28%). The majority of NABs and blood cultures performed were negative, but of the positive tests Staphylococcus aureus was the most prevalent bacteria. 86% (25/29) had an MRI before a diagnosis was made and 72% (13/18) had an NAB performed post-diagnosis.

CONCLUSIONS

MRI is a popular and helpful tool in diagnosing spinal osteomyelitis de novo. NAB cultures are often negative but can be useful in determining antibiotic treatment.

LEVEL OF EVIDENCE

Level IV.

Efficacy and safety of intravenous thiamylal in pediatric procedural sedation for magnetic resonance imaging

OBJECTIVE

To evaluate the efficacy and safety of intravenous (i.v.) thiamylal in pediatric magnetic resonance imaging (MRI) sedation.

METHODS

Infants and children from 1 month up to 8 years of age who underwent MRI in our hospital between April 2017 and March 2019 were included in this prospective observational study. Initial dose of 2 mg/kg thiamylal was given intravenously; however, additional doses were administered as needed. MRI was performed after adequate sedation was achieved. The primary endpoint was the success rate of MRI, while secondary endpoints were adverse events related to sedation, time to sedate, recovery time, and the dose of thiamylal.

RESULTS

A total of 118 patients were included in the analysis with median age and weight of 31.5 months (14.0-56.8 months) and 12.6 kg (9.5-15.7 kg), respectively. The success rate of MRI was 96.6% (114/118), and the median dose of thiamylal per body weight was 3.6 (2.8-4.0) mg/kg. The median time from the first dose of thiamylal to MRI was 7 min (4-10 min) and that from the end of MRI scanning to the confirmation of emergence was 8 min (5-25 min). Adverse events encountered included respiratory arrests (n = 3) and reduction in oxygen saturation (SpO₂; n = 9). There were no significant differences in the age, dose of thiamylal, sex, body weight, the American Society of Anesthesiologists physical status, and neurological abnormalities between the groups with and without respiratory complications.

CONCLUSION

This study demonstrated an adequate efficacy and safety of i.v. thiamylal, with rapid sedation and patient recovery.

Timeliness of care and adverse event profile in children undergoing general anesthesia or sedation for MRI: An observational prospective cohort study

Background and Aims

Anaesthesia for children undergoing magnetic resonance imaging (MRI) ranges from moderate to deep sedation in order to facilitate uninterrupted completion of the scan. While various intravenous and inhalational techniques of anaesthesia have their own merits and demerits, there is a paucity of comparative literature between the two in children undergoing diagnostic MRI.

Materials and Methods

This prospective observational cohort study was conducted at the Radiology suite of a 2800-bedded tertiary care hospital, wherein 107 unpremedicated children between the ages of 6 months to 15 years received either sedation with propofol infusion (Group GSP, n = 57) or inhalational anaesthesia with a laryngeal mask airway (Group GAL, n = 50). Primary outcome measures included time to induction and time to recovery. Secondary outcomes comprised the incidence of respiratory and non-respiratory adverse events in the two groups.

Results

The median time to induction was significantly shorter in GSP than GAL [7.00 (IQR 5.0, 10.0) versus 10.00 minutes (IQR 8.8, 13.0), P < 0.001]; the incidence of desaturation [8 (16.0%) in GAL, 1 (1.8%) in GSP, P = 0.012], laryngospasm [11 (22.4%) in GAL, 1 (1.8%) in GSP, P = 0.001] and emergence delirium (5 (10%) in GAL, 0 in GSP, P = 0.047) were significantly greater in the GAL group. There was no difference in the time to emergence, nausea and vomiting or bradycardia between the two groups.

Conclusion

Sedation with propofol infusion during paediatric MRI scan offers a short turnover time and favourable adverse event profile when compared to inhalational anaesthesia with an LMA.

Retrospective rigid motion correction of three-dimensional magnetic resonance fingerprinting of the human brain

PURPOSE

To obtain three-dimensional (3D), quantitative and motion-robust imaging with magnetic resonance fingerprinting (MRF).

METHODS

Our acquisition is based on a 3D spiral projection k-space scheme. We compared different orderings of trajectory interleaves in terms of rigid motion-correction robustness. In all tested orderings, we considered the whole dataset as a sum of 56 segments of 7-s duration, acquired sequentially with the same flip angle schedule. We performed a separate image reconstruction for each segment, producing whole-brain navigators that were aligned to the first segment using normalized correlation. The estimated rigid motion was used to correct the k-space data, and the aligned data were matched with the dictionary to obtain motion-corrected maps.

RESULTS

A significant improvement on the motion-affected maps after motion correction is evident with the suppression of motion artifacts. Correlation with the motionless baseline improved by 20% on average for both T₁ and T₂ estimations after motion correction. In addition, the average motion-induced quantification bias of 70 ms for T₁ and 18 ms for T₂ values was reduced to 12 ms and 6 ms, respectively, improving the reliability of quantitative estimations.

CONCLUSION

We established a method that allows correcting 3D rigid motion on a 7-s timescale during the reconstruction of MRF data using self-navigators, improving the image quality and the quantification robustness.

[Sedative effect of intranasal midazolam in neonates undergoing magnetic resonance imaging: a prospective single-blind randomized controlled study]

OBJECTIVE

To compare intranasal midazolam and intramuscular phenobarbital sodium for their sedative effect in neonates undergoing magnetic resonance imaging (MRI).

METHODS

A total of 70 neonates who underwent cranial MRI from September 2017 to March 2019 were randomized into an observation group and a control group, with 35 cases in each group. The observation group received intranasal drops of midazolam (0.3 mg/kg), and the control group received intramuscular injection of phenobarbital sodium (10 mg/kg). The sedation status of the neonates was evaluated using the Ramsay Sedation Scale. Meanwhile, the two groups were compared for the success rate of MRI procedure and incidence of adverse reactions.

RESULTS

In the observation group, the sedation score was the highest at 20 minutes post administration, then was gradually decreasing, and decreased to the lowest level at 70 minutes post administration. In the control group, the sedation score was the lowest at 10 minutes post administration, then was gradually increasing, and increased to the highest level at 40 minutes and 50 minutes post administration, followed by a gradual decrease. Comparison of the sedation score at each time period suggested that the sedation score was significantly higher in the observation group than in the control group within 40 minutes post administration (P<0.05), while there were no significant differences between the two groups in the sedation score after 40 minutes post administration (P>0.05). The success rate of MRI procedure was significantly higher in the observation group than in the control group (89% vs 69%, P<0.05). There was no significant difference between the two groups in the incidence of adverse reactions (P>0.05).

CONCLUSIONS

Intranasal midazolam is superior to intramuscular phenobarbital sodium in the sedative effect in neonates undergoing MRI, with the benefits of being fast, convenient, safe, and effective.

Drug selection for sedation and general anesthesia in children undergoing ambulatory magnetic resonance imaging

The demand for drug-induced sedation for magnetic resonance imaging (MRI) scans have substantially increased in response to increases in MRI utilization and growing interest in anxiety in children. Understanding the pharmacologic options for deep sedation and general anesthesia in an MRI environment is essential to achieve immobility for the successful completion of the procedure and ensure rapid and safe discharge of children undergoing ambulatory MRI. For painless diagnostic MRI, a single sedative/anesthetic agent without analgesia is safer than a combination of multiple sedatives. The traditional drugs, such as chloral hydrate, pentobarbital, midazolam, and ketamine, are still used due to the ease of administration despite low sedation success rate, prolonged recovery, and significant adverse events. Currently, dexmedetomidine, with respiratory drive preservation, and propofol, with high effectiveness and rapid recovery, are preferred for children undergoing ambulatory MRI. General anesthesia using propofol or sevoflurane can also provide predictable rapid time to readiness and scan times in infants or children with comorbidities. The selection of appropriate drugs as well as sufficient monitoring equipment are vital for effective and safe sedation and anesthesia for ambulatory pediatric MRI.

Effect of Intraoperative Sedation with Dexmedetomidine Versus Propofol on Acute Postoperative Pain Following Major Foot Surgery under Popliteal Sciatic Nerve Block: A Randomized Controlled Trial

Intravenous (IV) dexmedetomidine is reported to prolong analgesia following peripheral nerve blocks. Popliteal sciatic nerve block provides effective postoperative analgesia, but some patients still experience severe pain during the early postoperative period. We aimed to evaluate the postoperative analgesic effects of IV dexmedetomidine versus propofol in patients undergoing foot surgeries under popliteal sciatic nerve block. Forty patients were enrolled and randomly assigned to receive either IV propofol (n = 20) or IV dexmedetomidine (n = 20) for intraoperative sedation. All the patients received continuous popliteal sciatic nerve block. The corresponding drug infusion rate was adjusted to achieve a modified observer’s assessment of alertness/sedation score of 3 or 4. The primary outcome was postoperative cumulative opioid consumption during the first 24 h after surgery. Thirty-nine patients were analyzed. The median (interquartile ranges) postoperative cumulative opioid consumption during the first 24 h after surgery was significantly lower in the dexmedetomidine group (15 (7.5–16.9) mg) than in the propofol group (17.5 (15–25) mg) (p = 0.019). The time to first rescue analgesic request was significantly greater in the dexmedetomidine group than in the propofol group (11.8 ± 2.2 h vs. 10.0 ± 2.7 h, p = 0.030) without the prolonged motor blockade (p = 0.321). Intraoperative sedation with dexmedetomidine reduced postoperative opioid consumption and prolonged analgesic duration after a popliteal sciatic nerve block.

Newly Developed Methods for Reducing Motion Artifacts in Pediatric Abdominal MRI: Tips and Pearls

OBJECTIVE. The purpose of this article is to review established and emerging methods for reducing motion artifacts in pediatric abdominal MRI. CONCLUSION. Clearly understanding the strengths and limitations of motion reduction methods can enable practitioners of pediatric abdominal MRI to select and combine the appropriate techniques and potentially reduce the need for sedation and anesthesia.

Contrast-Induced Vomiting in Pediatric Patients Under Propofol Sedation: A Case Series

Gadolinium-based compounds are frequently used in contrast-enhanced magnetic resonance imaging studies. Rarely, adverse events have been reported with administration of these compounds, of which the most common are nausea and vomiting. Although well established in the adult literature, these adverse effects are less well described in the pediatric population, who often need sedation to complete imaging studies. In this case series, we present 3 children who experienced vomiting shortly after contrast administration while under sedation with propofol, which is known to have antiemetic properties. Although all 3 children recovered without complication, this case series illustrates the serious potential consequences of vomiting while sedated, and providers should be aware of these possible adverse events as pediatric sedation becomes more common outside the operating room.

Guidelines for Monitoring and Management of Pediatric Patients Before, During, and After Sedation for Diagnostic and Therapeutic Procedures

The safe sedation of children for procedures requires a systematic approach that includes the following: no administration of sedating medication without the safety net of medical/dental supervision, careful presedation evaluation for underlying medical or surgical conditions that would place the child at increased risk from sedating medications, appropriate fasting for elective procedures and a balance between the depth of sedation and risk for those who are unable to fast because of the urgent nature of the procedure, a focused airway examination for large (kissing) tonsils or anatomic airway abnormalities that might increase the potential for airway obstruction, a clear understanding of the medication's pharmacokinetic and pharmacodynamic effects and drug interactions, appropriate training and skills in airway management to allow rescue of the patient, age- and size-appropriate equipment for airway management and venous access, appropriate medications and reversal agents, sufficient numbers of appropriately trained staff to both carry out the procedure and monitor the patient, appropriate physiologic monitoring during and after the procedure, a properly equipped and staffed recovery area, recovery to the presedation level of consciousness before discharge from medical/dental supervision, and appropriate discharge instructions. This report was developed through a collaborative effort of the American Academy of Pediatrics and the American Academy of Pediatric Dentistry to offer pediatric providers updated information and guidance in delivering safe sedation to children.

Sedation Strategies for Procedures Outside the Operating Room

With the rapid development of diagnostic and therapeutic procedures performed outside the operating room (OR), the need for appropriate sedation care has emerged in importance to ensure the safety and comfort of patients and clinicians. The preparation and administration of sedatives and sedation care outside the OR require careful attention, proper monitoring systems, and clinically useful sedation guidelines. This literature review addresses proper monitoring and selection of sedatives for diagnostic and interventional procedures outside the OR. As the depth of sedation increases, respiratory depression and cardiovascular suppression become serious, necessitating careful surveillance using appropriate monitoring equipment.

Gauging potential risk for patients in pediatric radiology by review of over 2,000 incident reports

BACKGROUND

Incident reporting can be used to inform imaging departments about adverse events and near misses.

OBJECTIVE

To study incident reports submitted during a 5-year period at a large pediatric imaging system to evaluate which imaging modalities and other factors were associated with a greater rate of filed incident reports.

MATERIALS AND METHODS

All incident reports filed between 2013 and 2017 were reviewed and categorized by modality, patient type (inpatient, outpatient or emergency center) and use of sedation/anesthesia. The number of incident reports was compared to the number of imaging studies performed during that time period to calculate an incident report rate for each factor. Statistical analysis of whether there were differences in these rates between factors was performed.

RESULTS

During the study period, there were 2,009 incident reports filed and 1,071,809 imaging studies performed for an incident report rate of 0.19%. The differences in rates by modality were statistically significant (P=0.0001). There was a greater rate of incident reports in interventional radiology (1.54%) (P=0.0001) and in magnetic resonance imaging (MRI) (0.62%) (P=0.001) as compared to other imaging modalities. There was a higher incident report rate for inpatients (0.34%) as compared to outpatient (0.1%) or emergency center (0.14%) (P=0.0001). There was a higher rate of incident reports for patients under sedation (1.27%) as compared to non-sedated (0.12%) (P=0.0001).

CONCLUSION

Using incident report rates as a proxy for potential patient harm, the areas of our pediatric radiology service that are associated with the greatest potential for issues are interventional radiology, sedated patients, and inpatients. The areas associated with the least risk are ultrasound (US) and radiography. Safety improvement efforts should be focused on the high-risk areas.

A retrospective comparison of propofol to dexmedetomidine for pediatric magnetic resonance imaging sedation in patients with mucopolysaccharidosis type II

BACKGROUND

Mucopolysaccharidosis type II patients are reported to have an elevated incidence of difficult airway. Propofol is a commonly used sedative for magnetic resonance imaging in pediatric patients, but patients who receive it may exhibit dose-dependent upper airway obstruction and respiratory depression. Dexmedetomidine also provides adequate procedural sedation with a relatively low risk of airway obstruction. Accordingly, we introduced the use of dexmedetomidine in our practice to reduce the risk of airway obstruction during magnetic resonance imaging procedures.

AIMS

The aim of this study was to evaluate the incidence of artificial airway interventions in patients sedated with propofol and compare it to that in patients sedated with dexmedetomidine in patients with mucopolysaccharidosis type II during magnetic resonance imaging procedures.

METHODS

All mucopolysaccharidosis type II patients undergoing magnetic resonance imaging at our institution between April 2014 and February 2018 were included in this study. The patients were divided into two groups according to whether they were managed before and after the introduction of dexmedetomidine: those who were sedated with propofol (group P) and those who were sedated with dexmedetomidine (group D).

RESULTS

Forty-six sedations were performed in 27 patients. Artificial airway interventions were significantly more frequent during propofol-based than dexmedetomidine-based sedation: 14 of 32 (43.8%) in group P and 1 of 14 (7.1%) in group D (odds ratio, 10.11; 95% confidence interval, 1.18-86.85; P = 0.018). Time to awake and time to discharge were similar between groups. Changes in hemodynamic variables also did not significantly differ between groups.

CONCLUSION

Dexmedetomidine provides an adequate level of sedation and is associated with lower rates of artificial airway interventions compared to propofol. Therefore, dexmedetomidine may offer advantages for preserving the native airway compared to propofol when administered during magnetic resonance imaging scans in patients with mucopolysaccharidosis type II.