Pediatric Critical Care Patients Research Articles

Relationship Between Driving Pressure Measured During First 24 Hours and Mortality in Pediatric Critical Care Patients

Relationship Between Driving Pressure Measured During First 24 Hours and Mortality in Pediatric Critical Care Patients

A Near Real-Time Risk Analytics Algorithm Predicts Elevated Lactate Levels in Pediatric Cardiac Critical Care Patients.

Postoperative pediatric congenital heart patients are predisposed to develop low-cardiac output syndrome. Serum lactate (lactic acid [LA]) is a well-defined marker of inadequate systemic oxygen delivery. We hypothesized that a near real-time risk index calculated by a noninvasive predictive analytics algorithm predicts elevated LA in pediatric patients admitted to a cardiac ICU (CICU). Ten tertiary CICUs in the United States and Pakistan. Retrospective observational study performed to validate a hyperlactatemia (HLA) index using T3 platform data (Etiometry, Boston, MA) from pediatric patients less than or equal to 12 years of age admitted to CICU (n = 3,496) from January 1, 2018, to December 31, 2020. Patients lacking required data for module or LA measurements were excluded. Physiologic algorithm used to calculate an HLA index that incorporates physiologic data from patients in a CICU. The algorithm uses Bayes' theorem to interpret newly acquired data in a near real-time manner given its own previous assessment of the physiologic state of the patient. A total of 58,168 LA measurements were obtained from 3,496 patients included in a validation dataset. HLA was defined as LA level greater than 4 mmol/L. Using receiver operating characteristic analysis and a complete dataset, the HLA index predicted HLA with high sensitivity and specificity (area under the curve 0.95). As the index value increased, the likelihood of having higher LA increased (p < 0.01). In the validation dataset, the relative risk of having LA greater than 4 mmol/L when the HLA index is less than 1 is 0.07 (95% CI: 0.06-0.08), and the relative risk of having LA less than 4 mmol/L when the HLA index greater than 99 is 0.13 (95% CI, 0.12-0.14). These results validate the capacity of the HLA index. This novel index can provide a noninvasive prediction of elevated LA. The HLA index showed strong positive association with elevated LA levels, potentially providing bedside clinicians with an early, noninvasive warning of impaired cardiac output and oxygen delivery. Prospective studies are required to analyze the effect of this index on clinical decision-making and outcomes in pediatric population.

Using Two Statewide Medical Operations Coordination Centers to Load Balance in Pediatric Hospitals During a Severe Respiratory Surge in the United States.

Report on the use of two statewide Medical Operations Coordination Centers (MOCCs) to manage a rapid surge in pediatric acute and critical care patient needs. Brief report. The states of Washington and Oregon during the pediatric respiratory surge in November 2022/December 2022 which overwhelmed existing pediatric acute and critical care hospital capacity. Pediatric patients requiring hospitalization in Washington and Oregon. Adaptations to the use of two existing statewide MOCCs to provide pediatric patient load balancing through surveillance, modifications of existing referral agreements, coordinated expansion of resources, activation of regional crisis standards of care, and integration of pediatric critical care physicians from Harborview Medical Center as subject matter experts (SMEs). The Washington and Oregon MOCCs managed 183 pediatric requests from hospitals unable to transfer pediatric patients between November 1, 2022, and December 14, 2022. Sixteen percent of requests were for children younger than 3 months and 37% were for children between 3 months and 1 year; most had acute viral respiratory disease. Requests for children older than 13 years old were primarily intentional drug ingestions. Fifty-eight percent were for critically ill children and 17% originated from critical access hospitals. Washington's SMEs were utilized in nearly a quarter of cases with the disposition changing in 38% of these. Washington and Oregon statewide MOCCs have leveraged centralized coordination to effectively load balance a surge in pediatric patients which has overwhelmed existing pediatric hospital resources. Centralized coordination and surveillance informed pediatric hospitals and policy makers of unmet clinical needs and facilitated rapid expansion of clinical capacity and modifications to referral processes. Integration of pediatric SMEs enabled efficient triage of these resources. MOCCs provide an adaptable centralized resource for addressing surge and have been effective in managing overwhelmed pediatric hospital resources in Washington and Oregon.

A new marker for the evaluation of nutrition in pediatric critical care patients: Zonulin

Objective: Zonulin is a biomarker of increased intestinal permeability. Malnutrition is strongly associated with prolonged length of stay, increased infection, and mortality. This study aimed to determine how the serum zonulin level is affected in patients in PICU, and evaluate the relationship between pre-albumin and Vitamin D. Method: 35 critically ill pediatric patients were included in the study. The control group was formed of 25 healthy children. The albumin, pre-albumin, Vitamin D, and zonulin levels were examined in patients with findings of infection that regressed during ICU follow-up. The differences between prealbumin levels, Vitamin D, and zonulin were analyzed with the Mann-Whitney-U Test. Results: The most common reason for admission to the PICU was respiratory failure in 12 patients. The Vitamin D level was determined to have a mean of 28.8±12.3ng/mL and &lt;29ng/mL in 9 patients. The albumin level was determined to be mean 3.3±0.6 mg/dL, and the pre-albumin level was mean 17.8±7.4mg/dL. The serum zonulin levels in critically ill patients were statistically significantly higher than in the control group. The difference between the zonulin levels of patients with pre-albumin values was statistically significant. The zonulin levels of patients with a Vitamin D value &lt;20 were found to be statistically significantly higher than the zonulin levels of patients with a Vitamin D value &gt;20. Conclusion: The higher zonulin level in critically ill pediatric patients may be associated with prolonged catabolic processes, exposure to oxidative and hypoxic stress, and bacterial translocation development associated with all of these. The results of the current study showed a statistically significant negative correlation between Vitamin D and zonulin levels. Therefore, the relationship between low Vitamin D values and a high zonulin level may be useful in evaluating chronic malnutrition. The serum zonulin level selected as a biomarker for the surveillance and management of nutrition in critically ill pediatric patients is not an appropriate marker.

Study Limitations and Harmonious Discord of Results Reveal Melody to Public Health Measures.

Study Limitations and Harmonious Discord of Results Reveal Melody to Public Health Measures.

Use of Aminophylline to Reverse Acute Kidney Injury in Pediatric Critical Care Patients.

Acute kidney injury (AKI) is a complication encountered in 18% to 51% of pediatric critical care patients admitted for treatment of other primary diagnoses and is an independent risk factor for increased morbidity and mortality. Aminophylline has shown promise as a medication to treat AKI, but published studies have shown conflicting results. Our study seeks to assess the reversal of AKI following the administration of aminophylline in critically ill pediatric patients. We performed a single-institution retrospective chart review of pediatric inpatients who were diagnosed with AKI and subsequently treated with non-continuous dose aminophylline between January 2016 and December 2018. Data were collected beginning 2 days prior to the initial dose of aminophylline through completion of the 5-day aminophylline course. Nineteen therapies among 17 patients were included in analysis. Twelve of the therapies resulted in resolution of AKI during the study period. We observed urine output increase of 19% (p = 0.0063) on the day following initiation of aminophylline therapy in the subset of patients whose AKI resolved. Trends toward decreased serum creatinine and lower inotropic support were also noted. Based on these findings, aminophylline could be considered a potentially effective medication for use as rescue therapy in critically ill children with AKI. Limitations include small study population and retrospective nature. Further research in this area with a larger study population and a randomized control trial would allow for better characterization of the efficacy of aminophylline in reversal of AKI.

Artificial Intelligence to Improve Health Outcomes in the NICU and PICU: A Systematic Review.

Artificial intelligence (AI) technologies are increasingly used in pediatrics and have the potential to help inpatient physicians provide high-quality care for critically ill children. We aimed to describe the use of AI to improve any health outcome(s) in neonatal and pediatric intensive care. PubMed, IEEE Xplore, Cochrane, and Web of Science databases. We used peer-reviewed studies published between June 1, 2010, and May 31, 2020, in which researchers described (1) AI, (2) pediatrics, and (3) intensive care. Studies were included if researchers assessed AI use to improve at least 1 health outcome (eg, mortality). Data extraction was conducted independently by 2 researchers. Articles were categorized by direct or indirect impact of AI, defined by the European Institute of Innovation and Technology Health joint report. Of the 287 publications screened, 32 met inclusion criteria. Approximately 22% (n = 7) of studies revealed a direct impact and improvement in health outcomes after AI implementation. Majority were in prototype testing, and few were deployed into an ICU setting. Among the remaining 78% (n = 25) AI models outperformed standard clinical modalities and may have indirectly influenced patient outcomes. Quantitative assessment of health outcomes using statistical measures, such as area under the receiver operating curve (56%; n = 18) and specificity (38%; n = 12), revealed marked heterogeneity in metrics and standardization. Few studies have revealed that AI has directly improved health outcomes for pediatric critical care patients. Further prospective, experimental studies are needed to assess AI's impact by using established implementation frameworks, standardized metrics, and validated outcome measures.

Long-Term Functional Outcomes After Sepsis for Adult and Pediatric Critical Care Patients-Protocol for a Systematic Review.

Objective: Sepsis is responsible for a massive burden of disease, with a global estimate of 48.9 million cases resulting in approximately 11 million deaths annually. Survivors of sepsis may also experience long-term impairments that can persist for years after hospital discharge. These cognitive, physical and/or psychosocial deficits may contribute to a lower health related quality of life and represent a significant ongoing burden to the individual, the community and the health care system. We aim to systematically review the available evidence on long-term functional and quality of life outcomes after sepsis in children and adults.Data Sources: Medline, EMBASE, and CINAHL will be searched for eligible studies.Study Selection: Studies of adult and pediatric survivors of sepsis who had required admission to intensive care will be included. A minimum 6 month prospective follow up will be required. Accepted outcomes will be any validated measure of health-related quality of life (HRQoL) or functional deficits, using the Post-Intensive Care Syndrome (PICS) framework of cognitive, physical or psychosocial outcomes.Data Extraction: Data extraction will include information related to study characteristics, population characteristics, clinical criteria and outcomes.Data Synthesis: Studies meeting the inclusion criteria will be presented descriptively separated for pediatric and adult age groups. Meta-analysis will be attempted if sufficient primary data from several studies applying the same tests and outcomes are available. The primary outcome is HRQoL after sepsis; secondary outcomes include the functional status at follow-up.Conclusions: This systematic review will define the long-term impact of sepsis survivorship. The data will contribute to informing patient, clinician and stakeholder decisions and guide further research and resource management.

The Utility of Point-of-Care Ultrasound in the Pediatric Intensive Care Unit.

Objectives: Point of care ultrasound (POCUS) in adult critical care environments has become the standard of care in many hospitals. A robust literature shows its benefits for both diagnosis and delivery of care. The utility of POCUS in the pediatric intensive care unit (PICU), however, is understudied. This study describes in a series of PICU patients the clinical indications, protocols, findings and impact of pediatric POCUS on clinical management. Design: Retrospective analysis of 200 consecutive POCUS scans performed by a PICU physician. Patients: Pediatric critical care patients who required POCUS scans over a 15-month period. Setting: The pediatric and cardiac ICUs at a tertiary pediatric care center. Interventions: Performance of a POCUS scan by a pediatric critical care attending with advanced training in ultrasonography. Measurement and Main Results: A total of 200 POCUS scans comprised of one or more protocols (lung and pleura, cardiac, abdominal, or vascular diagnostic protocols) were performed on 155 patients over a 15-month period. The protocols used for each scan reflected the clinical question to be answered. These 200 scans included 133 thoracic protocols, 110 cardiac protocols, 77 abdominal protocols, and 4 vascular protocols. In this series, 42% of scans identified pathology that required a change in therapy, 26% confirmed pathology consistent with the ongoing plans for new therapy, and 32% identified pathology that did not result in initiation of a new therapy. Conclusions: POCUS performed by a trained pediatric intensivist provided useful clinical information to guide patient management.

A Meta-analysis of the Utility of Red Cell Distribution Width as a Biomarker to Predict Outcomes in Pediatric Illness (PROSPERO CRD42020208777)

AbstractRed cell distribution width (RDW) is an average of the variation in red blood cell (RBC) sizes reported on a complete blood count. An elevated RDW indicates a pathological process that is affecting erythropoiesis. Studies showed that as the severity of disease process increases, the RDW often increases as well. Particularly in resource-limited countries, RDW has been studied as an outcome predictor for conditions in a variety of disciplines and is offered as an adjunct monitoring tool that is cost effective, readily available, and indicative of pathological processes amenable to intervention. Particularly in pediatric critical care settings, RDW has been shown to be a reliable tool for surveillance of disease states such as sepsis. Despite the increased attention of RDW as a marker for disease outcome, collective evaluation on the utility of RDW as a marker for outcome in pediatric critical care settings is lacking. We offer a systematic review and meta-analysis of published studies to assess the ability of RDW to predict illness severity and mortality among pediatric critical care patients. Among eight studies of over 4,800 patients, we found over a two-fold increase in odds for mortality in critically ill children whose RDW was above 15.7%. This is the first systematic review of RDW being used to predict mortality in critically ill children and findings of this study may prompt early intervention in the pediatric critical care setting.

Effect of Live Versus Recorded Music on Children Receiving Mechanical Ventilation and Sedation.

Music is often used as a nonpharmacological pain management strategy, but little evidence is available about its role in pediatric critical care patients. To determine the effect of a live music intervention versus a recorded music intervention on heart rate, blood pressure, and respiratory rate in pediatric critical care patients receiving mechanical ventilation and sedation. An exploratory randomized controlled trial was performed in a pediatric intensive care unit. Participants were randomly allocated to receive a live music intervention with standard care or a recorded music intervention with standard care. Each intervention was delivered by a board-certified music therapist for 15 minutes. Heart rate, respiratory rate, and blood pressure were measured at baseline and at 15-minute intervals for 60 minutes after the intervention. A total of 33 patients aged 0 to 2 years completed the study: 17 were assigned to the live music group and 16 to the recorded music group. In the live music group, a significant reduction in heart rate was observed immediately after the intervention and was sustained at 60 minutes after the intervention. Although the live music group also exhibited a downward trend in blood pressure, those differences were not significant. The results of this study indicate that live music interventions may be more effective than recorded music interventions in reducing pain and anxiety in pediatric critical care patients. The advantage of live music may be due to the adaptability of the music delivery by a trained music therapist.

Machine learning model for early prediction of acute kidney injury (AKI) in pediatric critical care

BackgroundAcute kidney injury (AKI) in pediatric critical care patients is diagnosed using elevated serum creatinine, which occurs only after kidney impairment. There are no treatments other than supportive care for AKI once it has developed, so it is important to identify patients at risk to prevent injury. This study develops a machine learning model to learn pre-disease patterns of physiological measurements and predict pediatric AKI up to 48 h earlier than the currently established diagnostic guidelines.MethodsEHR data from 16,863 pediatric critical care patients between 1 month to 21 years of age from three independent institutions were used to develop a single machine learning model for early prediction of creatinine-based AKI using intelligently engineered predictors, such as creatinine rate of change, to automatically assess real-time AKI risk. The primary outcome is prediction of moderate to severe AKI (Stage 2/3), and secondary outcomes are prediction of any AKI (Stage 1/2/3) and requirement of renal replacement therapy (RRT). Predictions generate alerts allowing fast assessment and reduction of AKI risk, such as: “patient has 90% risk of developing AKI in the next 48 h” along with contextual information and suggested response such as “patient on aminoglycosides, suggest check level and review dose and indication”.ResultsThe model was successful in predicting Stage 2/3 AKI prior to detection by conventional criteria with a median lead-time of 30 h at AUROC of 0.89. The model predicted 70% of subsequent RRT episodes, 58% of Stage 2/3 episodes, and 41% of any AKI episodes. The ratio of false to true alerts of any AKI episodes was approximately one-to-one (PPV 47%). Among patients predicted, 79% received potentially nephrotoxic medication after being identified by the model but before development of AKI.ConclusionsAs the first multi-center validated AKI prediction model for all pediatric critical care patients, the machine learning model described in this study accurately predicts moderate to severe AKI up to 48 h in advance of AKI onset. The model may improve outcome of pediatric AKI by providing early alerting and actionable feedback, potentially preventing or reducing AKI by implementing early measures such as medication adjustment.

High incidence of stroke and mortality in pediatric critical care patients with COVID-19 in Peru.

IntroductionPediatric critical care patients with COVID-19 treated in Peru have higher mortality than those previously reported from other countries. Pediatric providers have reported a high number of patients without comorbidities presenting with hemorrhagic strokes associated with COVID-19. We present a study analyzing the factors associated with mortality in this setting.MethodsProspective case–control study that included patients <17 years old admitted to a pediatric critical care unit with a positive test confirming COVID-19. The primary outcome was mortality. Fisher’s exact test and the Mann–Whitney U test were used for the analysis.ResultsForty-seven patients were admitted to critical care. The mortality of our study is 21.3%. The mortality of patients with neurological presentation was 45.5%, which was significantly higher than the mortality of acute COVID-19 (26.7%) and MIS-C (4.8%), p 0.18. Other risk factors for mortality in our cohort were strokes and comorbidities. Only one patient presenting with hemorrhagic stroke had an undiagnosed comorbidity.ConclusionCerebrovascular events associated with COVID-19 in pediatric patients, including infants, must be recognized as one of the more severe presentations of this infection in pediatric patients.Impact Pediatric patients with COVID-19 can present with hemorrhagic and ischemic strokes on presentation.Neurological presentation in pediatric patients with COVID-19 has high mortality.Mortality of pediatric patients with COVID-19 is associated with comorbidities.Pediatric presentation and outcomes of COVID-19 in different regions can be novel to previously described.

Modified Glasgow Coma Scale and the Alert Verbal Painful Unresponsive Scale for Assessing the Level of Consciousness in Pediatric Critical Care Patients—A Comparative Study

AbstractAltered consciousness is a common problem encountered in the pediatric emergency department. Modified Glasgow coma scale (MGCS) has been widely used in pediatric intensive care units (PICUs) for assessing the level of consciousness in children with various illnesses. To compare utility of alert verbal painful unresponsive (AVPU) scale and MGCS for assessing level of consciousness of critically ill patients admitted to PICU. A prospective observational study was conducted at Acharya Vinoba Bhave Rural Hospital in Maharashtra, India on children above the age of 30 days admitted to the PICU from September 2018 to August 2019, fulfilling the inclusion criteria, after obtaining informed consent from the parents. Level of consciousness of the enrolled patients was assessed using the AVPU scale and MGCS. One-way analysis of variance technique was used for data analysis. A total of 74 children were included in the study. A good correlation was observed between the two scales and mean MGCS score of 13.8 (13–15), 11.3 (11–12), 8.09 (7–9), and 3 corresponded to A, V, P, and U, respectively. AVPU scale was comparable to MGCS in assessing level of consciousness in children admitted to PICU. AVPU can be used for initial evaluation of level of consciousness in children presenting with altered consciousness. More detailed MGCS can be used to assess the improvement over time and to decide further treatment strategy.

P0102 / #696: DIFFERENCES IN SERUM ALBUMIN AND PREALBUMIN CONCENTRATIONS IN PATIENTS WHO RECEIVED PARENTERAL NUTRITION IN THE PEDIATRIC INTENSIVE CARE UNIT.

Aims & Objectives: Nutritional support is a therapeutic strategy to avoid intrahospital malnutrition. Parenteral nutrition (PN) is indicated in patients whose gastrointestinal tract isn’t able to use, this condition is frequent in pediatric critical care patients; who also have metabolic alterations inherent in the metabolic response. Therefore the aim of the study is analyse changes in serum albumin and prealbumin concentrations during administration of parenteral nutrition Methods: Study desing: Retrospective cohort study Population: Pediatric patients who er 1 month and up to 17 years who received PN for at least 3 days during their PICU stay and were obtained the albumin and prealbumin values when they started PN and when it was discontinued. Duration From June to December 2019 A wilcoxon test was used to analyse the difference between the start and end values of albumin and prealbumin Results: 33 patients were analyzed (67% boys, 37% girls), with a mean age of 4.9 years. 45% were acutely malnourished (11% mild, 14 moderate, 20% severe). The mean of PN was 10 days. There are statistical significant difference between the albumine and prealbumine concentrations at the beginning and at the end of the TNP Conclusions: PN could improve biochemical outcomes for patients admitted to the PICU.Significant changes in albumin and prealbumin concentrations were found after of the implementation of PN.

Transcultural adaptation and characteristics of the Spanish version of the COMFORT Behavior Scale in pediatric critical care patients.

To determine the measurement properties of the Spanish version of the COMFORT Behavior Scale developed by van Dijk et al. (2000) in pediatric critical care patients. Prospective observational and psychometric study. Level III Intensive Care Area at a university's children hospital. A total of 311 children with median age of 5.07 years (IQR = 0.9-11.7). None. To determine the measurement properties the Spanish version of the COMFORT Behavior Scale was simultaneous administered by 2nurses to 311 patients admitted to an eighteen-bed critical care unit of a third level pediatric hospital. The Spanish version of the COMFORT Behavior Scale obtained a Cronbach alpha coefficient of 0.715 and it is a tool made up of 3factors with 2items: 1) alertness and physical movement; 2) calmness/agitation and respiratory response/crying, and 3) muscle tone and facial tension. The COMFORT B was adapted to Spanish and it has shown to be a valid an reliable tool to assess comfort in a group of children admitted to an Spanish Intensive Care Unit.

Transcultural adaptation and characteristics of the Spanish version of the COMFORT Behavior Scale in pediatric critical care patients

ObjectivesTo determine the measurement properties of the Spanish version of the COMFORT Behavior Scale developed by van Dijk et al (2000) in paediatric critical care patients. DesignProspective observational and psychometric study. SettingLevel III Intensive Care Area at a university’s children hospital. PatientsA total of 311 children with median age of 5.07 years (IQR = 0.9-11.7). InterventionsNone. Principal variables and resultsTo determine the measurement properties the Spanish version of the COMFORT Behavior Scale was simultaneous administered by two nurses to 311 patients admitted to an eighteen-bed critical care unit of a third level paediatric hospital. The Spanish version of the COMFORT Behavior Scale obtained a Cronbach alpha coefficient of 0.715 and it is a tool made up of three factors with two items in each domain: i) alertness and physical movement; ii) calmness/agitation and respiratory response/crying, and iii) muscle tone and facial tension. ConclusionsThe COMFORT B was adapted to Spanish and it has shown to be a valid an reliable tool to assess comfort in a group of children admitted to an Spanish Intensive Care Unit.

Pediatric Cardiac Critical Care Transport and Palliative Care: A Case Series.

To present our center's experience with terminal extubation in 3 palliative critical care home transports from the Pediatric Cardiac Intensive Unit. All cases were identified from our Cardiovascular intensive care unit ( CVICU). Patients were terminally ill children with no other surgical or medical option who were transported home between 2014 and 2018, for terminal extubation and end-of-life care according to their families' wishes. The patients were 7, 9 months, and 19 years; and they had very complex and chronic conditions. The families were approached by the CVICU staff during multidisciplinary meetings, where goals of care were established. Parental expectations were clarified, and palliative care team was involved, as well as home hospice was arranged pre transfer. The transfer process was discussed and all the needs were established. All patients had unstable medical conditions, with needs for transport for withdrawal of life support and death at home. Each case needed a highly trained team to support life while in transport. The need of these patients required coordination with home palliative care services, as well as community resources due to difficulty to get in their homes. Transportation of pediatric cardiac critical care patients for terminal extubation at home is a relatively infrequent practice. It is a feasible alternative for families seeking out of the hospital end-of-life care for their critically ill and technology dependent children. Our single-center experience supports the need for development of formal programs for end-of-life critical care transports.

Retrospective cohort study on factors associated with mortality in high-risk pediatric critical care patients in the Netherlands

BackgroundHigh-risk patients in the pediatric intensive care unit (PICU) contribute substantially to PICU-mortality. Complex chronic conditions (CCCs) are associated with death. However, it is unknown whether CCCs also increase mortality in the high-risk PICU-patient. The objective of this study is to determine if CCCs or other factors are associated with mortality in this group.MethodsRetrospective cohort study from a national PICU-database (2006–2012, n = 30,778). High-risk PICU-patients, defined as patients < 18 years with a predicted mortality risk > 30% according to either the recalibrated Pediatric Risk of Mortality-II (PRISM) or the Paediatric Index of Mortality 2 (PIM2), were included. Patients with a cardiac arrest before PICU-admission were excluded.ResultsIn total, 492 high-risk PICU patients with mean predicted risk of 24.8% (SD 22.8%) according to recalibrated PIM2 and 40.0% (SD 23.8%) according to recalibrated PRISM were included of which 39.6% died. No association was found between CCCs and non-survival (odds ratio 0.99; 95% CI 0.62–1.59). Higher Glasgow coma scale at PICU admission was associated with lower mortality (odds ratio 0.91; 95% CI 0.87–0.96).ConclusionsComplex chronic conditions are not associated with mortality in high-risk PICU patients.

PEEP Generated by High-Flow Nasal Cannula in a Pediatric Model.

High-flow nasal cannulas (HFNC) have been increasingly used in the pediatric critical care patient population. There are different theories about the mechanism by which HFNC reduces work of breathing, including diminishing upper airway dead space by the washout of carbon dioxide. However, one of the likely primary mechanisms by which HFNC reduces work of breathing is by generating PEEP. There are limited data assessing the PEEP delivered by moderate flows (8-50 L/min) of HFNC, which are used most commonly in pediatric patients. Pediatric upper-airway models were created with 5 different nares produced by a 3-dimensional printer and connected to a lung simulator. Age-specific flows were delivered via the 5 different setups. Pressure throughout the simulated airway was measured at HFNC flows of 6-60 L/min with 25%, 50%, and 75% air leak to simulate open-mouth breathing. PEEPs of 1.2-36 cm H2O were generated with HFNC flows of 6-60 L/min. In general, for each specific cannula, increasing the flow and decreasing the air leak resulted in higher levels of PEEP delivered (P < .001 and > 10% difference). Changes in lung mechanics as generated by the lung simulator to simulate different patient ages resulted in the establishment of different levels of PEEP. HFNCs deliver varying amounts of PEEP at the alveolar level with flows of 6-60 L/min. Increasing flow and decreasing leak resulted in the generation of greater PEEP. PEEP levels differed across cannulas and model weights at the same leak level, likely due to differences in the nasal interface between the HFNC device and the model nares.