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.

Monitoring the biomechanical and physiological effects of postural changes during leisure chair sitting.

BACKGROUND: Individuals with limited mobility can spend prolonged periods in leisure chairs, increasing their risk of developing a seated acquired pressure ulcer. The present study aims to use objective measures of posture and tissue viability to identify the associated risks of leisure chair related pressure ulcers. METHODS: Healthy participants (n = 13) were recruited to sit on a leisure chair with either a viscoelastic foam or air cushion. Participants were asked to adopt four different postures for a period of 10 min followed by a 10 min refractory period. Measurements at the leisure chair-participant interface included interface pressure, transcutaneous tissue gas tensions at the ischial tuberosities, accelerometer data collected from the sternum and subjective comfort levels. RESULTS: Results indicated that interface pressures remained consistent, with peak pressure index values of less than 60 mmHg across all conditions. A proportion of participants exhibited decreased oxygen tensions associated with increased carbon dioxide tensions during one or more test condition. This was particularly prevalent during the right lean posture on the air cushion (46%). In all cases, normal tissue viability was restored during standing. The accelerometer was able to detect significant changes (p < 0.05) in relative trunk angles during slump and right lean when compared to optimal sitting posture. CONCLUSION: Commercially available leisure chairs have little evidence to support their pressure relieving properties. This study revealed that a proportion of healthy individuals demonstrated a compromised tissue viability in specific postures. Further research is required to assess the impact of these sitting conditions in vulnerable individuals.

Informed Consent in Decision-Making in Pediatric Practice.

Informed consent should be seen as an essential part of health care practice; parental permission and childhood assent is an active process that engages patients, both adults and children, in their health care. Pediatric practice is unique in that developmental maturation allows, over time, for increasing inclusion of the child's and adolescent's opinion in medical decision-making in clinical practice and research. This technical report, which accompanies the policy statement "Informed Consent in Decision-Making in Pediatric Practice" was written to provide a broader background on the nature of informed consent, surrogate decision-making in pediatric practice, information on child and adolescent decision-making, and special issues in adolescent informed consent, assent, and refusal. It is anticipated that this information will help provide support for the recommendations included in the policy statement.

Venous thromboembolism prophylaxis in the pediatric trauma population.

BACKGROUND/PURPOSE: The aim of this study was to review evidence-based literature addressing pertinent questions about venous thromboembolism (VTE) after traumatic injury in children. METHODS: Data were obtained from English-language articles identified through Pubmed published from 1995 until November 2012, and from bibliographies of relevant articles. Studies were included if they contributed evidence to one of the following questions. In the pediatric traumatic injury population: (1) What is the overall incidence of VTE? (2) Is age (adolescence versus pre-adolescence) associated with higher VTE incidence? (3) Which risk factors are associated with higher VTE incidence? (4) Does mechanical and/or pharmacological prophylaxis impact outcomes? RESULTS: Eighteen articles were included in this systematic review. The evidence regarding each question was evaluated, graded by author consensus, and summarized. CONCLUSIONS: The overall incidence of VTE is low. Older (>13years) and more severely injured patients are at higher VTE risk. Additional factors including injury type or presence of a central venous catheter also place a patient at higher VTE risk. Implementation of a risk-based clinical practice guideline for VTE prophylaxis has been associated with reduced symptomatic VTE at one institution. Randomized, prospective trials analyzing outcomes of VTE prophylaxis in pediatric trauma victims are needed.

Central venous access via external jugular vein in children.

OBJECTIVE: To determine the success rate and complications of using the external jugular (EJ) vein for central venous access in pediatric patients. METHODS: Prospective cohort study of children who underwent attempts at EJ vein central venous access while receiving care in an 11-bed pediatric intensive care unit at an urban children's hospital. RESULTS: Over a period of 15 months, 50 patients had EJ venous cannulation attempts. Central venous access was achieved in 45 patients (90%). Successful central venous access was performed in 4 children (50%) younger than 1 year and in 36 older children (98%). Catheter-tip malposition on chest radiograph required subsequent line manipulation in 2 patients. No complications of pneumothorax or carotid artery puncture occurred during line insertion. The catheters were used for an average of 7.5 days (range, 1-28 days). Catheter malfunction occurred in 4 (1.21/100 catheter-days), and catheter-related bloodstream infections occurred in 2 patients (6.04/1000 catheter-days). No thrombotic complications were clinically detected. CONCLUSIONS: The EJ vein is a viable site for central venous access with a low complication rate in pediatric patients.

Relative and absolute quantitative expression profiling of cytochromes P450 using isotope-coded affinity tags.

The development of a novel method for absolute quantification of proteins based on isotope-coded affinity tagging using ICAT reagents is described. The method exploits synthetic peptide standards to determine protein content at the femtomole level in biological samples. The approach is generally applicable to any subset of proteins, but is particularly appropriate for quantitative analysis of multiple, closely related isoforms, and for hydrophobic proteins that are poorly represented in 2-D gels. Relative and absolute quantification techniques are applied to an important group of microsomal metabolic enzymes, the cytochromes P450 (P450), which are critical in determining the disposition, safety and efficacy of drugs in man. Measurement of the P450 induction profile in response to chemicals is a fundamental aspect of drug safety evaluation and is currently achieved by low-throughput methods employing poorly discriminatory antibodies or substrates. Tagging technology is shown to supersede conventional methods for P450 profiling in terms of discriminatory power and throughput, exemplified by the simultaneous detection of distinct induction profiles for cyp2c subfamily members in response to phenobarbitone: cyp2c29 expression, but not cyp2c40 or cyp2c50, was induced threefold by treatment. This technology should abbreviate the drug development pathway, and provide a widely applicable, rapid means of quantifying proteins.

Pediatric extracorporeal membrane oxygenation (ECMO): a review of the first ten years of experience at the Medical University of South Carolina.

ECMO can be life saving in pulmonary emergencies unresponsive to conventional ICU support. ECMO technology and expertise has increased immensely over the last decade. Our experience, and others, has demonstrated that the earlier the referral to an ECMO center, the better chance of survival these patients will have. Our survival results exceed the national average and we have used this therapy in a wide variety of disease processes. Long-term sequelae in survivors are infrequent, as most patients return to normal pulmonary function.

Assessing the effects of diurnal variation on the composition of human parotid saliva: quantitative analysis of native peptides using iTRAQ reagents.

Changes in salivary composition correlate with disease susceptibility, disease state, or both. However, use of saliva for diagnostic purposes is complicated by the gland-specific effects of circadian rhythm or diurnal variation. We recently characterized a suite of peptides in the < or =10-kDa fraction of human parotid saliva that included many novel species. In this study, we used novel iTRAQ labeling chemistry to investigate possible diurnal effects on peptide generation. We collected samples produced by gustatory stimulation as the ductal secretions at four time points under conditions that minimized proteolysis, pooled them according to collection time, and isolated the LMW fractions. Samples collected at each collection time were derivatized with a different isobaric iTRAQ reagent. The labeled samples were combined, separated by reversed-phase HPLC, co-spotted with matrix on MALDI targets, and analyzed by MALDI TOF/TOF mass spectrometry. With this approach, we achieved relative quantification of the parotid peptides at four time points. In several cases, abundance during the day changed dramatically. iTRAQ tagging improved the efficiency of MS/MS fragmentation, which in turn allowed the identification of several novel peptides. Our results demonstrated both the utility of this method and the importance of diurnal effects on the composition of the human parotid saliva peptidome.

Life-threatening pediatric poisonings.

Initial therapy of the poisoned child should follow the basic principles of advanced life support and include support of a patent airway and adequate oxygenation, ventilation, and circulation. Ingestion of certain substances require agent-specific therapy which may modify the standard resuscitative approach. Children can present following unknown or unsuspected ingestions. Any child with unexplained altered level of consciousness, respiratory, circulatory derangement, seizures or metabolic abnormalities should be considered for toxic ingestion. Knowing the typical signs and symptoms of the common toxic syndromes can help identification of the unknown ingestion. Recommendations for decontamination, detoxification, and antidotal therapies have changed over the past 10 years. Clinicians should be aware of the community resources available to help guide the evaluation and management of the poisoned child.