Conservative versus liberal oxygenation targets in critically ill children (Oxy-PICU): a UK multicentre, open, parallel-group, randomised clinical trial.

BACKGROUND: The optimal target for systemic oxygenation in critically ill children is unknown. Liberal oxygenation is widely practiced, but has been associated with harm in paediatric patients. We aimed to evaluate whether conservative oxygenation would reduce duration of organ support or incidence of death compared to standard care. METHODS: Oxy-PICU was a pragmatic, multicentre, open-label, randomised controlled trial in 15 UK paediatric intensive care units (PICUs). Children admitted as an emergency, who were older than 38 weeks corrected gestational age and younger than 16 years receiving invasive ventilation and supplemental oxygen were randomly allocated in a 1:1 ratio via a concealed, central, web-based randomisation system to conservative peripheral oxygen saturations ([SpO2] 88-92%) or liberal (SpO2 >94%) targets. The primary outcome was the duration of organ support at 30 days following random allocation, a rank-based endpoint with death either on or before day 30 as the worst outcome (a score equating to 31 days of organ support), with survivors assigned a score between 1 and 30 depending on the number of calendar days of organ support received. The primary effect estimate was the probabilistic index, a value greater than 0·5 indicating more than 50% probability that conservative oxygenation is superior to liberal oxygenation for a randomly selected patient. All participants in whom consent was available were included in the intention-to-treat analysis. The completed study was registered with the ISRCTN registry (ISRCTN92103439). FINDINGS: Between Sept 1, 2020, and May 15, 2022, 2040 children were randomly allocated to conservative or liberal oxygenation groups. Consent was available for 1872 (92%) of 2040 children. The conservative oxygenation group comprised 939 children (528 [57%] of 927 were female and 399 [43%] of 927 were male) and the liberal oxygenation group included 933 children (511 [56%] of 920 were female and 409 [45%] of 920 were male). Duration of organ support or death in the first 30 days was significantly lower in the conservative oxygenation group (probabilistic index 0·53, 95% CI 0·50-0·55; p=0·04 Wilcoxon rank-sum test, adjusted odds ratio 0·84 [95% CI 0·72-0·99]). Prespecified adverse events were reported in 24 (3%) of 939 patients in the conservative oxygenation group and 36 (4%) of 933 patients in the liberal oxygenation group. INTERPRETATION: Among invasively ventilated children who were admitted as an emergency to a PICU receiving supplemental oxygen, a conservative oxygenation target resulted in a small, but significant, greater probability of a better outcome in terms of duration of organ support at 30 days or death when compared with a liberal oxygenation target. Widespread adoption of a conservative oxygenation saturation target (SpO2 88-92%) could help improve outcomes and reduce costs for the sickest children admitted to PICUs. FUNDING: UK National Institute for Health and Care Research Health Technology Assessment Programme.

Tracheostomy in children is associated with neutrophilic airway inflammation.

BACKGROUND: Tracheostomies in children are associated with significant morbidity, poor quality of life, excess healthcare costs and excess mortality. The underlying mechanisms facilitating adverse respiratory outcomes in tracheostomised children are poorly understood. We aimed to characterise airway host defence in tracheostomised children using serial molecular analyses. METHODS: Tracheal aspirates, tracheal cytology brushings and nasal swabs were prospectively collected from children with a tracheostomy and controls. Transcriptomic, proteomic and metabolomic methods were applied to characterise the impact of tracheostomy on host immune response and the airway microbiome. RESULTS: Children followed up serially from the time of tracheostomy up to 3 months postprocedure (n=9) were studied. A further cohort of children with a long-term tracheostomy were also enrolled (n=24). Controls (n=13) comprised children without a tracheostomy undergoing bronchoscopy. Long-term tracheostomy was associated with airway neutrophilic inflammation, superoxide production and evidence of proteolysis when compared with controls. Reduced airway microbial diversity was established pre-tracheostomy and sustained thereafter. CONCLUSIONS: Long-term childhood tracheostomy is associated with a inflammatory tracheal phenotype characterised by neutrophilic inflammation and the ongoing presence of potential respiratory pathogens. These findings suggest neutrophil recruitment and activation as potential exploratory targets in seeking to prevent recurrent airway complications in this vulnerable group of patients.

The Infant KIdney Dialysis and Utrafiltration (I-KID) Study: A Stepped-Wedge Cluster-Randomized Study in Infants, Comparing Peritoneal Dialysis, Continuous Venovenous Hemofiltration, and Newcastle Infant Dialysis Ultrafiltration System, a Novel Infant Hemodialysis Device.

OBJECTIVES: Renal replacement therapy (RRT) options are limited for small babies because of lack of available technology. We investigated the precision of ultrafiltration, biochemical clearances, clinical efficacy, outcomes, and safety profile for a novel non-Conformité Européenne-marked hemodialysis device for babies under 8 kg, the Newcastle Infant Dialysis Ultrafiltration System (NIDUS), compared with the current options of peritoneal dialysis (PD) or continuous venovenous hemofiltration (CVVH). DESIGN: Nonblinded cluster-randomized cross-sectional stepped-wedge design with four periods, three sequences, and two clusters per sequence. SETTING: Clusters were six U.K. PICUs. PATIENTS: Babies less than 8 kg requiring RRT for fluid overload or biochemical disturbance. INTERVENTIONS: In controls, RRT was delivered by PD or CVVH, and in interventions, NIDUS was used. The primary outcome was precision of ultrafiltration compared with prescription; secondary outcomes included biochemical clearances. MEASUREMENTS AND MAIN RESULTS: At closure, 97 participants were recruited from the six PICUs (62 control and 35 intervention). The primary outcome, obtained from 62 control and 21 intervention patients, showed that ultrafiltration with NIDUS was closer to that prescribed than with control: sd controls, 18.75, intervention, 2.95 (mL/hr); adjusted ratio, 0.13; 95% CI, 0.03-0.71; p = 0.018. Creatinine clearance was smallest and least variable for PD (mean, sd ) = (0.08, 0.03) mL/min/kg, larger for NIDUS (0.46, 0.30), and largest for CVVH (1.20, 0.72). Adverse events were reported in all groups. In this critically ill population with multiple organ failure, mortality was lowest for PD and highest for CVVH, with NIDUS in between. CONCLUSIONS: NIDUS delivers accurate, controllable fluid removal and adequate clearances, indicating that it has important potential alongside other modalities for infant RRT.

Protocol for a Randomized Multiple Center Trial of Conservative Versus Liberal Oxygenation Targets in Critically Ill Children (Oxy-PICU): Oxygen in Pediatric Intensive Care.

OBJECTIVES: Oxygen administration is a fundamental part of pediatric critical care, with supplemental oxygen offered to nearly every acutely unwell child. However, optimal targets for systemic oxygenation are unknown. Oxy-PICU aims to evaluate the clinical effectiveness and cost-effectiveness of a conservative peripheral oxygen saturation (Sp o2 ) target of 88-92% compared with a liberal target of more than 94%. DESIGN: Pragmatic, open, multiple-center, parallel group randomized control trial with integrated economic evaluation. SETTING: Fifteen PICUs across England, Wales, and Scotland. PATIENTS: Infants and children age more than 38 week-corrected gestational age to 16 years who are accepted to a participating PICU as an unplanned admission and receiving invasive mechanical ventilation with supplemental oxygen for abnormal gas exchange. INTERVENTION: Adjustment of ventilation and inspired oxygen settings to achieve an Sp o2 target of 88-92% during invasive mechanical ventilation. MEASUREMENTS AND MAIN RESULTS: Randomization is 1:1 to a liberal Sp o2 target of more than 94% or a conservative Sp o2 target of 88-92% (inclusive), using minimization with a random component. Minimization will be performed on: age, site, primary reason for admission, and severity of abnormality of gas exchange. Due to the emergency nature of the treatment, approaching patients for written informed consent will be deferred to after randomization. The primary clinical outcome is a composite of death and days of organ support at 30 days. Baseline demographics and clinical status will be recorded as well as daily measures of oxygenation and organ support, and discharge outcomes. This trial received Health Research Authority approval on December 23, 2019 (reference: 272768), including a favorable ethical opinion from the East of England-Cambridge South Research Ethics Committee (reference number: 19/EE/0362). Trial findings will be disseminated in national and international conferences and peer-reviewed journals.

Permissive versus restrictive temperature thresholds in critically ill children with fever and infection: a multicentre randomized clinical pilot trial.

BACKGROUND: Fever improves pathogen control at a significant metabolic cost. No randomized clinical trials (RCT) have compared fever treatment thresholds in critically ill children. We performed a pilot RCT to determine whether a definitive trial of a permissive approach to fever in comparison to current restrictive practice is feasible in critically ill children with suspected infection. METHODS: An open, parallel-group pilot RCT with embedded mixed methods perspectives study in four UK paediatric intensive care units (PICUs) and associated retrieval services. Participants were emergency PICU admissions aged > 28 days to < 16 years receiving respiratory support and supplemental oxygen. Subjects were randomly assigned to permissive (antipyretic interventions only at ≥ 39.5 °C) or restrictive groups (antipyretic interventions at ≥ 37.5 °C) whilst on respiratory support. Parents were invited to complete a questionnaire or take part in an interview. Focus groups were conducted with staff at each unit. Outcomes were measures of feasibility: recruitment rate, protocol adherence and acceptability, between group separation of temperature and safety. RESULTS: One hundred thirty-eight children met eligibility criteria of whom 100 (72%) were randomized (11.1 patients per month per site) without prior consent (RWPC). Consent to continue in the trial was obtained in 87 cases (87%). The mean maximum temperature (95% confidence interval) over the first 48 h was 38.4 °C (38.2-38.6) in the restrictive group and 38.8 °C (38.6-39.1) in the permissive group, a mean difference of 0.5 °C (0.2-0.8). Protocol deviations were observed in 6.8% (99/1438) of 6-h time periods and largely related to patient comfort in the recovery phase. Length of stay, duration of organ support and mortality were similar between groups. No pre-specified serious adverse events occurred. Staff (n = 48) and parents (n = 60) were supportive of the trial, including RWPC. Suggestions were made to only include invasively ventilated children for the duration of intubation. CONCLUSION: Uncertainty around the optimal fever threshold for antipyretic intervention is relevant to many emergency PICU admissions. A more permissive approach was associated with a modest increase in mean maximum temperature. A definitive trial should focus on the most seriously ill cases in whom antipyretics are rarely used for their analgesic effects alone. TRIAL REGISTRATION: ISRCTN16022198 . Registered on 14 August 2017.

Mortality and morbidity in community-acquired sepsis in European pediatric intensive care units: a prospective cohort study from the European Childhood Life-threatening Infectious Disease Study (EUCLIDS).

BACKGROUND: Sepsis is one of the main reasons for non-elective admission to pediatric intensive care units (PICUs), but little is known about determinants influencing outcome. We characterized children admitted with community-acquired sepsis to European PICUs and studied risk factors for mortality and disability. METHODS: Data were collected within the collaborative Seventh Framework Programme (FP7)-funded EUCLIDS study, which is a prospective multicenter cohort study aiming to evaluate genetic determinants of susceptibility and/or severity in sepsis. This report includes 795 children admitted with community-acquired sepsis to 52 PICUs from seven European countries between July 2012 and January 2016. The primary outcome measure was in-hospital death. Secondary outcome measures were PICU-free days censured at day 28, hospital length of stay, and disability. Independent predictors were identified by multivariate regression analysis. RESULTS: Patients most commonly presented clinically with sepsis without a source (n = 278, 35%), meningitis/encephalitis (n = 182, 23%), or pneumonia (n = 149, 19%). Of 428 (54%) patients with confirmed bacterial infection, Neisseria meningitidis (n = 131, 31%) and Streptococcus pneumoniae (n = 78, 18%) were the main pathogens. Mortality was 6% (51/795), increasing to 10% in the presence of septic shock (45/466). Of the survivors, 31% were discharged with disability, including 24% of previously healthy children who survived with disability. Mortality and disability were independently associated with S. pneumoniae infections (mortality OR 4.1, 95% CI 1.1-16.0, P = 0.04; disability OR 5.4, 95% CI 1.8-15.8, P < 0.01) and illness severity as measured by Pediatric Index of Mortality (PIM2) score (mortality OR 2.8, 95% CI 1.3-6.1, P < 0.01; disability OR 3.4, 95% CI 1.8-6.4, P < 0.001). CONCLUSIONS: Despite widespread immunization campaigns, invasive bacterial disease remains responsible for substantial morbidity and mortality in critically ill children in high-income countries. Almost one third of sepsis survivors admitted to the PICU were discharged with some disability. More research is required to delineate the long-term outcome of pediatric sepsis and to identify interventional targets. Our findings emphasize the importance of improved early sepsis-recognition programs to address the high burden of disease.

Randomized Study of Early Continuous Positive Airways Pressure in Acute Respiratory Failure in Children With Impaired Immunity (SCARF) ISRCTN82853500.

OBJECTIVES: Previous trials in adults with impaired immunity and respiratory failure suggest that early noninvasive ventilation avoids endotracheal intubation and improves survival. No randomized clinical trials have addressed this question in children. DESIGN: We undertook an open, parallel-group randomized trial in three pediatric hospitals. SUBJECTS: Children with impaired immunity and acute respiratory failure defined as tachypnoea (> 90th centile); a new requirement for supplemental oxygen; and new chest radiograph infiltrates. INTERVENTIONS: Children were randomly assigned to early PICU admission for continuous positive airways pressure (early continuous positive airways pressure) or to standard care. The primary outcome was endotracheal intubation by 30 days. MEASUREMENTS AND MAIN RESULTS: One-hundred fourteen children met inclusion criteria of whom 42 were randomized between January 2013 and January 2016. There was no significant difference in endotracheal intubation by 30 days with early continuous positive airways pressure (10/21; 48%) compared with standard care (5/21; 24%), odds ratio 2.9 (0.8-10.9), p value equals to 0.11. However, 30-day mortality was significantly higher with early continuous positive airways pressure (7/21; 33%) compared with standard care (1/21; 5%), odds ratio 10.0 (1.1-90.6), p value equals to 0.041. Mortality at 90 days was early continuous positive airways pressure (11/21; 52%) versus standard care (4/21; 19%), odds ratio 4.7 (1.2-18.6), p value equals to 0.029, whereas mortality at 1 year was similar early continuous positive airways pressure (13/21; 61.9%) versus standard care (9/21; 42.7%), odds ratio 2.2 (0.6-7.4), p value equals to 0.22. There were two serious adverse events: early continuous positive airways pressure (pneumothorax) and standard care (hemothorax). CONCLUSIONS: This study provided no evidence to support early PICU admission for continuous positive airways pressure in children with acute respiratory failure and impaired immunity. There was a trend toward increased endotracheal intubation and a higher early mortality in the early continuous positive airways pressure group.

Attitudes towards fever amongst UK paediatric intensive care staff.

The role played by fever in the outcome of critical illness in children is unclear. This survey of medical and nursing staff in 35 paediatric intensive care units and transport teams in the United Kingdom and Ireland established attitudes towards the management of children with fever. Four hundred sixty-two medical and nursing staff responded to a web-based survey request. Respondents answered eight questions regarding thresholds for temperature control in usual clinical practice, indications for paracetamol use, and readiness to participate in a clinical trial of permissive temperature control. The median reported threshold for treating fever in clinical practice was 38 °C (IQR 38-38.5 °C). Paracetamol was reported to be used as an analgesic and antipyretic but also for non-specific comfort indications. There was a widespread support for a clinical trial of a permissive versus a conservative approach to fever in paediatric intensive care units. Within a trial, 58% of the respondents considered a temperature of 39 °C acceptable without treatment. CONCLUSIONS: Staff on paediatric intensive care units in the United Kingdom and Ireland tends to treat temperatures within the febrile range. There was a willingness to conduct a randomized controlled trial of treatment of fever. What is known: • The effect of fever on the outcome in paediatric critical illness is unknown. • Paediatricians have traditionally been reluctant to allow fever in sick children. What is new: • Paediatric intensive care staff report a tendency towards treating fever, with a median reported treatment threshold of 38 °C. • There is widespread support amongst PICU staff in the UK for a randomized controlled trial of temperature in critically ill children. • Within a trial setting, PICU staff attitudes to fever are more permissive than in clinical practice.

The development and implementation of an inter-professional simulation based pediatric acute care curriculum for ward health care providers.

An interprofessional, simulation based, acute care course for ward health care providers was developed and implemented with the objectives of teaching identification of deteriorating patients, practicing crisis resource management and basic life support skills, and using the SBAR (Situation Background Assessment Recommendation) communication tool. Thirty-eight physicians and 51 nurses attended the four separate courses. Nine questions on a 5-point Likert scale and two open-ended questions revealed that over 95% of respondents strongly agreed/agreed that facilitators encouraged active participation, lectures were presented in an interesting manner, and that simulations were useful for practical skills and for practicing communication. Open-ended questions revealed that participants felt more confident, understood the importance of communication, roles, teamwork and valued the day. Based on this evaluation, the program was regarded as feasible and acceptable to all health care providers.

Intracranial pressure and cerebral perfusion pressure responses to head elevation changes in pediatric traumatic brain injury.

OBJECTIVES: To determine the effect of and dynamic interaction between head elevation on intracranial pressure and cerebral perfusion pressure in severe pediatric traumatic head injury. DESIGN: Prospective, randomized, interventional cohort study. SETTING: Two tertiary pediatric critical care referral units. PATIENTS: Ten children admitted with severe traumatic brain injury defined as Glasgow Coma Score ≤ 8 necessitating intracranial pressure monitoring (10 yrs ± 5 SD; range 2-16 yrs). INTERVENTIONS: Head elevation was randomly increased or decreased between 0 and 40 degrees from baseline level (30 degrees) in increments or decrements of 10 degrees. MEASUREMENTS AND MAIN RESULTS: Intracranial pressure and arterial blood pressure were continuously recorded in combination with time-stamped clinical notations. Data were available for analysis in eight subjects (seven males and one female; mean age, 10 yrs ± SD 5; range, 2-16 yrs) during 18 protocol sessions. This resulted in a total of 66 head-of-the-bed challenges. To compare results for a given change in head-of-the-bed elevation across age, we transformed head-of-the-bed angle to change in height (cm) at the level of Monro's foramen. An increase in head elevation of 10 cm resulted in an average change in intracranial pressure of -3.9 mm Hg (SD ± 3.2 mm Hg; p < .001), whereas cerebral perfusion pressure remained unchanged (0.1 ± 5.6 mm Hg; p = .957). Individual subjects showed marked variability in intracranial pressure change (range, -8.4 to +1.9 mm Hg/10 cm). The overall regression analysis for intracranial pressure response was change in intracranial pressure = -0.39/cm Δh, r2 = 0.42, and p < .001, where Δh is the change in vertical height at the level of foramen of Monro attributable to a change in the head of the bed. CONCLUSIONS: In severe pediatric traumatic brain injury, the relationship between change in head of the bed and change in intracranial pressure was negative and linear. The lowest intracranial pressure was usually, but not always, achieved at highest head-of-the-bed angles. The effect size of a head-of-the-bed angle change depended, in part, on the subject's height. In contrast, cerebral perfusion pressure was mostly unaffected by head-of-the-bed changes.

Organizational characteristics of European pediatric onco-critical care: An international cross-sectional survey.

Background: Intensified treatment protocols have improved survival of pediatric oncology patients. However, these treatment protocols are associated with increased treatment-related morbidity requiring admission to pediatric intensive care unit (PICU). We aimed to describe the organizational characteristics and processes of care for this patient group across PICUs in Europe. Methods: A web-based survey was sent to PICU directors or representative physicians between February and June 2021. Results: Responses were obtained from 77 PICUs of 12 European countries. Organizational characteristics were similar across the different countries of Europe. The median number of PICU beds was 12 (IQR 8-16). The majority of the PICUs was staffed by pediatric intensivists and had a 24/7 intensivist coverage. Most PICUs had a nurse-to-patient ratio of 1:1 or 1:2. The median numbers of yearly planned and unplanned PICU admissions of pediatric cancer patients were 20 (IQR 10-45) and 10 (IQR 10-30, respectively. Oncology specific practices within PICU were less common in participating centres. This included implementation of oncology protocols in PICU (30%), daily rounds of PICU physicians on the wards (13%), joint mortality and morbidity meetings or complex patients' discussions (30% and 40%, respectively) and participation of parents during clinical rounds (40%). Conclusion: Our survey provides an overview on the delivery of critical care for oncology patients in PICU across European countries. Multidisciplinary care for these vulnerable and challenging patients remains complex and challenging. Future studies need to determine the effects of differences in PICU organization and processes of care on patients' outcome.

Tracheostomy trends in paediatric intensive care.

Paediatric tracheostomy is most commonly performed in children on the paediatric intensive care unit (PICU) to facilitate long-term ventilation. We sought to identify trends in UK tracheostomy practice in PICUs. Data were analysed from 250 261 admissions, including 4409 children tracheostomised between 2003 and 2017. The incidence of tracheostomy in 2017 was approximately half that in 2003 (incidence rate ratio=0.48, 95% CI 0.40 to 0.57). The percentage of patients tracheostomised during a PICU admission, as a proportion of all admissions, was 2.44% (n=319) in 2003 and reduced to 0.97% (n=180) in 2017. Nevertheless, we identified great variability in practice between different PICUs with tracheostomy rates between 0.0% and 4.0% of all admissions. Risk-adjusted PICU mortality was comparable between tracheostomised children and all admissions to PICU.

Establishing and augmenting views on the acceptability of a paediatric critical care randomised controlled trial (the FEVER trial): a mixed methods study.

OBJECTIVE: To explore parent and staff views on the acceptability of a randomised controlled trial investigating temperature thresholds for antipyretic intervention in critically ill children with fever and infection (the FEVER trial) during a multi-phase pilot study. DESIGN: Mixed methods study with data collected at three time points: (1) before, (2) during and (3) after a pilot trial. SETTING: English, Paediatric Intensive Care Units (PICUs). PARTICIPANTS: (1) Pre-pilot trial focus groups with pilot site staff (n=56) and interviews with parents (n=25) whose child had been admitted to PICU in the last 3 years with a fever and suspected infection, (2) Questionnaires with parents of randomised children following pilot trial recruitment (n=48 from 47 families) and (3) post-pilot trial interviews with parents (n=19), focus groups (n=50) and a survey (n=48) with site staff. Analysis drew on Sekhon et al's theoretical framework of acceptability. RESULTS: There was initial support for the trial, yet some held concerns regarding the proposed temperature thresholds and not using paracetamol for pain or discomfort. Pre-trial findings informed protocol changes and training, which influenced views on trial acceptability. Staff trained by the FEVER team found the trial more acceptable than those trained by colleagues. Parents and staff found the trial acceptable. Some concerns about pain or discomfort during weaning from ventilation remained. CONCLUSIONS: Pre-trial findings and pilot trial experience influenced acceptability, providing insight into how challenges may be overcome. We present an adapted theoretical framework of acceptability to inform future trial feasibility studies. TRIAL REGISTRATION NUMBERS: ISRCTN16022198 and NCT03028818.

Genetic variability in complement activation modulates the systemic inflammatory response syndrome in children.

OBJECTIVE: To determine the impact of genetic variability in complement activation on early development of the systemic inflammatory response syndrome (SIRS) in general pediatric critical care. DESIGN: Prospective, observational, cohort study. SETTING: A tertiary pediatric intensive care unit in the United Kingdom. PATIENTS: Children with at least one organ failure expected to stay in the intensive care unit >12 hrs, or an expected death within 12 hrs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 299 children were genotyped for functional polymorphisms in the complement activation cascade. We identified complement factor H as an important independent genetic modifier of SIRS/sepsis. Homozygosity for the complement factor H Y402H polymorphism, which is thought to reduce complement inhibition, was associated with less frequent SIRS/sepsis (the adjusted odds ratio for the homozygous variant complement factor H Y402H [CC] carriers was 0.3, 95% confidence interval, 0.1-0.7, p = .005). We also confirmed that structural and promoter variant mannose-binding lectin genotypes are a risk factor for SIRS/sepsis in pediatric critical care (adjusted odds ratio, 2.5; 95% confidence interval, 1.3-5.0, p = .008). Both findings were independent of clinical characteristics and other potentially confounding genetic polymorphisms in the innate immune system. CONCLUSIONS: Functional polymorphisms in the complement activation cascade modify the risk for early SIRS/sepsis in general pediatric critical care. The complement factor H Y402H variant allele is protective, whereas the mannose-binding lectin variant polymorphisms increase risk. A genotype that permits vigorous complement activation to an infectious or inflammatory insult may offer protection from development of systemic inflammation.

Pediatric tracheostomy: A large single-center experience.

OBJECTIVES: To describe the epidemiology, specifically the indications, complications, and outcomes, of pediatric tracheostomies performed in one tertiary referral unit. METHODS: Single-center retrospective cohort study of pediatric patients undergoing tracheostomy between May 2010 and May 2018 at the Newcastle upon Tyne Hospitals, United Kingdom. RESULTS: One hundred seventy-two pediatric tracheostomies were performed during the study period with a median age of 141 (interquartile range [IQR] 51-484) days. The most common primary indication was long-term ventilation (38.4%, 66 of 172), followed by weaning from ventilation in cardiac patients (22.1%, 38 of 172). Only 5.2% (9 of 172) of our cohort underwent tracheostomy for subglottic stenosis. The vast majority of tracheostomies were performed electively, with just 6.4% (11 of 172) performed as an emergency procedure. Early and late complication rates were 9.8% (15 of 153) and 40.0% (61 of 153), respectively. Tracheostomy decannulation was successful in 44.4% of children (68 of 153). The median duration the tracheostomy was in situ was 397 (IQR 106-708) days. All-cause mortality was 22.1% (38 of 172), with tracheostomy-related mortality at 1.2% (2 of 172). CONCLUSION: We report one of the largest contemporary case series of pediatric tracheostomies. Present-day pediatric tracheostomy is primarily performed as an elective procedure in ventilated children under the age of 1 year. Pediatric tracheostomy should be considered as a long-term intervention in many children. Nevertheless, a large proportion of children are ultimately decannulated. It is important to acknowledge the significant morbidity associated with this intervention and the small-but-present risk of tracheostomy-related mortality. LEVEL OF EVIDENCE: 4 Laryngoscope, 130:E375-E380, 2020.

Assessing the prediction potential of an in silico computer model of intracranial pressure dynamics.

OBJECTIVE: Traumatic brain injury (TBI) frequently results in poor outcome, suggesting that new approaches are needed. We hypothesized that a patient-specific in silico computer model of intracranial pressure (ICP) dynamics may predict the ICP response to therapy. DESIGN: In silico model analysis of prospectively collected data. SETTING: Twenty-three and 16-bed pediatric intensive care units in two tertiary care academic hospitals. PATIENTS: Nine subjects with severe TBI undergoing ICP monitoring (7 M/2 F, age range 3-17 years). INTERVENTIONS: Random changes in head-of-bed (HOB) (0 degrees , 10 degrees , 20 degrees , 30 degrees , 40 degrees ) elevation and respiratory rate (to achieve a DeltaETco2 = +/-3-4 mm Hg) were performed daily according to a study protocol as long as an intracerebral monitoring device was in place. METHODS AND MAIN OUTCOME MEASURES: A six-compartment dynamic ICP model was developed based on published equations and parametric data (baseline model parameter values). For each of 24 physiologic challenge sessions, patient-specific model parameter values were estimated that minimized the model fitness error, the difference between model-calculated ICP and observed ICP, both for baseline parameters and patient-specific parameter. Next, model prediction error was measured using two analyses. First, a "within" session analysis estimated parameter values using data from an initial Segment A, and then used those parameter values to predict the ICP during a later Segment B. The predicted ICP for B was compared with the observed ICP for B. Second, a "between" session analysis was performed. This analysis used parameter values estimated from earlier sessions to predict the ICP in later sessions. Fitness and prediction errors were measured in terms of mean absolute error (MAE). To normalize the errors, MAE was divided by the mean absolute deviation (MAD) for the associated segment or session, yielding a measure for both model fitness error and model prediction error that is favorable when <1. RESULTS: For baseline parameter values, MAE/MAD was <1 in 2 of 24 (8%) sessions. For session-specific parameter values, MAE/MAD was <1 in 21 of 24 (88%) sessions and <0.5 in 9 of 24 (38%) sessions. Sessions with low (<12 mm Hg) (n = 8; 33%) or high (>18 mm Hg) (n = 6; 25%) ICP had lower error than moderate ICP (12-18 mm Hg) (n = 10; 42%). MAE/MAD was <1 for 6 of 22 (27%) for within-session predictions and 3 of 31 (10%) for between-session predictions. CONCLUSIONS: The protocol for collecting physiologic data in subjects with severe TBI was feasible. The in silico ICP model with session-specific parameters accurately reproduced observed ICP response to changes in head-of-bed and respiration rate. We demonstrated modest success at predicting future ICP within a session and to a lesser extent between sessions.