PICU Doc On Call

Welcome to PICU Doc On Call, a podcast dedicated to current and aspiring pediatric intensivists. I'm Dr. Pradip Kamat from Children’s Healthcare of Atlanta/Emory University School of Medicine, and I’m Dr. Rahul Damania from Cleveland Clinic Children’s Hospital. We are two Pediatric ICU physicians passionate about medical education in the PICU. This podcast focuses on interesting PICU cases and their management in the acute care pediatric setting.

In today’s episode, we are excited to welcome Dr. Karen Zimowski, Assistant Professor of Pediatrics at Emory University School of Medicine and a practicing pediatric hematologist at Children’s Healthcare of Atlanta at the Aflac Blood & Cancer Center. Dr. Zimowski specializes in pediatric bleeding and clotting disorders.

A 16-year-old female with a complex medical history, including autoimmune thyroiditis and prior cerebral infarcts, was admitted to the PICU with acute chest pain and difficulty breathing. Despite being on low-dose aspirin, her oxygen saturation was 86% on room air. A CT angiography revealed a pulmonary embolism (PE) in the left lower lobe and signs of right heart strain. The patient was hemodynamically stable, and thrombolytic therapy was deferred in favor of anticoagulation. She was placed on BiPAP to improve her respiratory status. Her social history was negative for smoking, illicit drug use, or oral contraceptive use.

• Diagnosis: Pulmonary embolism (PE)
• Hemodynamics: Stable with no right ventricular (RV) strain on echocardiogram
• Management Focus: Anticoagulation and consultation with the hematology/thrombosis team

• Pathophysiology: Venous thromboembolism (VTE) in children involves components of Virchow’s triad: stasis of blood flow, endothelial injury, and hypercoagulability.
• Incidence: VTE is rare in the general pediatric population but increases significantly in hospitalized children.
• Age Distribution: Bimodal peaks in infants and adolescents aged 15-17 years.
• Risk Factors: Central venous lines, infections, congenital heart disease, cancer, and autoimmune disorders.

• Symptoms: Swelling, pain, warmth, and skin discoloration in the affected extremity.
• Specific Presentations:
• SVC syndrome from superior vena cava thrombosis
• Abdominal pain from portal vein thrombosis
• Hematuria from renal vein thrombosis
• Neurological symptoms from cerebral sinus venous thrombosis

• Imaging:
• Compression Doppler Ultrasonography: Primary method for diagnosing DVT in pediatric patients.
• MR Venography (MRV) and CT Venography (CTV): Used for abdominal and cerebral sinus thrombosis.
• Laboratory Studies:
• D-dimer: Useful in adults; limited specificity in children.
• Other Labs: Renal and liver function tests, CBC with differential, DIC panel.

• Unfractionated Heparin (UFH):
• Targets factors IIa and Xa; requires frequent monitoring.
• Adverse events: Bleeding and thrombocytopenia.
• Low Molecular Weight Heparin (LMWH):
• More predictable pharmacokinetics than UFH.
• Advantages include ease of administration and lower risk of HIT.
• Vitamin K Antagonists (VKAs):
• Used for long-term anticoagulation.
• Requires regular INR monitoring.
• Direct Oral Anticoagulants (DOACs):
• Dabigatran, Rivaroxaban, and Apixaban used in pediatric VTE.
• Advantages: No routine monitoring required, predictable effects.

In this episode, we discussed the intricacies of VTE diagnosis and management in pediatric patients. We thank Dr. Karen Zimowski for sharing her expertise on anticoagulation and hemostasis in the PICU. For more episodes and our Doc on Call management cards, visit picudoconcall.org.

Stay tuned for our next episode, and thank you for listening!

1. Fuhrman & Zimmerman - Textbook of Pediatric Critical Care: Thrombosis in Pediatric Critical Care.
2. American Society of Hematology 2018 Guidelines for Management of Venous Thromboembolism: Treatment of Pediatric Venous Thromboembolism.
3. Antithrombotic Therapy in Neonates and Children: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines.
4. O’Brien, SH, Stanek JR, Witmer CM, Raffini L. The Continued Rise of Venous Thromboembolism Across US Children’s Hospitals. Pediatrics (2022).

Welcome to PICU Doc On Call, where Dr. Pradip Kamat from Children’s Healthcare of Atlanta/Emory University School of Medicine and Dr. Rahul Damania from Cleveland Clinic Children’s Hospital delve into the intricacies of Pediatric Intensive Care Medicine. In this special episode of PICU Doc on Call shorts, we dissect the Alveolar Gas Equation—a fundamental concept in respiratory physiology with significant clinical relevance.

Key Concepts Covered:

• Alveolar Gas Equation Demystified: Dr. Rahul explains the Alveolar Gas Equation, which calculates the partial pressure of oxygen in the alveoli (PAO2). This equation, PAO2 = FiO2 (Patm - PH2O) - (PaCO2/R), is essential in understanding hypoxemia and the dynamics of gas exchange in the lungs.
• Calculating PAO2: Using the Alveolar Gas Equation, the hosts demonstrate how to calculate PAO2 at sea level, emphasizing the influence of atmospheric pressure, fraction of inspired oxygen (FiO2), water vapor pressure, arterial carbon dioxide pressure (PaCO2), and respiratory quotient (R) on oxygenation.
• A-a Gradient and Hypoxemia: The A-a gradient, derived from the Alveolar Gas Equation, is discussed in the context of hypoxemia evaluation. Understanding the causes of hypoxemia, including ventilation/perfusion (V/Q) mismatch, anatomical shunt, diffusion defects, and hypoventilation, is crucial for clinical diagnosis and management.
• Clinical Scenarios and A-a Gradient Interpretation: Through a clinical scenario, the hosts elucidate how different conditions affect the A-a gradient and oxygenation, providing insights into respiratory pathophysiology and differential diagnosis.
• Clinical Implications and Management Strategies: The hosts highlight the clinical significance of the Alveolar Gas Equation in assessing oxygenation status, diagnosing gas exchange abnormalities, and tailoring respiratory management strategies in the pediatric intensive care setting.

Key Takeaways:

• Utility of the Alveolar Gas Equation: Understanding and applying the Alveolar Gas Equation is essential for evaluating oxygenation and diagnosing respiratory abnormalities.
• Interpreting A-a Gradient: A normal A-a gradient suggests alveolar hypoventilation as the likely cause of hypoxemia, whereas elevated gradients indicate other underlying pathologies.
• Clinical Relevance: Recognizing the clinical implications of the Alveolar Gas Equation aids in accurate diagnosis and optimal management of respiratory conditions in pediatric intensive care patients.

Conclusion:

Join Dr. Kamat and Dr. Damania as they unravel the complexities of the Alveolar Gas Equation, providing valuable insights into respiratory physiology and its clinical applications. Don’t forget to subscribe, share your feedback, and visit picudoconcall.org for more educational content and resources.

References:

• Fuhrman & Zimmerman - Textbook of Pediatric Critical Care Chapter: Physiology of the respiratory system. Chapter 42. Khemani et al. Pages 470-481
• Rogers textbook of Pediatric intensive care: Chapter 44. Respiratory physiology. Akong K et al. Pages 691-721
• Respiratory Physiology for the Anesthesiologist. Bigatello L and Pesenti A, Anesthesiology 2019; 130: 1064-77

Welcome to PICU Doc On Call, A Podcast Dedicated to Current and Aspiring Intensivists.

• Hosts:
• Dr. Pradip Kamat: Children’s Healthcare of Atlanta/Emory University School of Medicine
• Dr. Rahul Damania: Cleveland Clinic Children’s Hospital

Introduction:

• Pediatric Intensive Care Unit (PICU) physicians passionate about medical education in the acute care pediatric setting
• Episode focus: A case of a 23-month-old ex-28 week premie presenting with sudden high fever and rapidly rising ETCO2 during surgery

Case Presentation:

• Presented by Dr. Rahul Damania
• 23-month-old ex-28 week premie intubated during hernia repair surgery
• Noticed rapidly rising ETCO2, unprovoked tachycardia, and elevated temperature
• Transferred to PICU, exhibiting rigidity, clenched jaw, metabolic acidosis, and elevated lactate.
• Consideration of Malignant Hyperthermia (MH) crisis

Key Points:

• Elevated temperature, hypercapnia, metabolic acidosis, and unprovoked tachycardia raise concern for MH
• Organized discussion on pathophysiology, clinical signs, symptoms, and management

Multiple Choice Question:

• Diagnosis of MH crisis during scoliosis repair
• Correct Answer: D) Sarcoplasmic reticulum
• Dantrolene acts on the sarcoplasmic reticulum to inhibit calcium release, crucial in MH management

Clinical Presentation of MH Crisis:

• Tachycardia, acidosis, muscle stiffness, and hyperthermia are hallmark features
• Potential life-threatening complications underscore the urgency of recognition and treatment

Triggers and Pathophysiology of MH Crisis:

• Triggered by inhalational agents and depolarizing neuromuscular blocking agents
• Pathophysiology involves defective Ryanodine receptor leading to uncontrolled calcium release

Differential Diagnosis:

• Includes sepsis, thyroid storm, pheochromocytoma, and neuroleptic malignant syndrome
• Differentiation from similar conditions crucial for accurate management

Diagnostic Approach:

• High clinical suspicion
• Genetic testing (ryanodine receptor gene sequencing) and Caffeine Halothane Contracture Test (CHCT) for diagnosis
• Immediate workup during crisis includes blood gas, lactate, CPK, CMP, and urine analysis

General Management Framework:

• MH crisis is a medical emergency requiring rapid intervention
• Dantrolene Na administration, supportive measures, and continuous monitoring in PICU
• Utilization of Malignant Hyperthermia carts and involvement of specialized hotlines

Clinical Pearls and Pitfalls:

• Early recognition is crucial.
• Proper administration of Dantrolene Na without delay
• Extended monitoring period in PICU to ensure stability

Conclusion:

• Importance of recognizing and managing MH crisis
• Feedback, subscription, and reviews encouraged
• Website picudoconcall.org for additional resources

References:

• Fuhrman & Zimmerman - Textbook of Pediatric Critical Care Chapter
• Malignant Hyperthermia Association of the United States
• What is MH?
• [Managing a crisis](https://www.mhaus.org/ healthcare-professionals/managing-a-crisis/)
• Rosenbaum HK, Rosenberg H. UpToDate: Malignant hyperthermia: diagnosis and management of acute crisis.

Show Introduction

• Welcome to PICU Doc On Call, a podcast dedicated to current and aspiring intensivists.
• Hosted by Dr. Pradip Kamat and Dr. Rahul Damania

Case Presentation

• A 14-year-old female with a history of depression and oppositional defiant disorder presents with dizziness, slurring speech, and is pale appearance.
• The mother noticed symptoms of dizziness, stumbling, and sleepiness.
• The patient had a prior suicide attempt.
• Vital signs: HR 50 bpm, BP 75/40, GCS 10.
• The initial workup reveals hyperglycemia, and she is stabilized and admitted to the PICU.

Key Aspects of Ingestion Work-up

• History and physical exam are crucial.
• Stratify acute or chronic ingestions.
• Consider baseline medications and coingestants.
• Perform initial screening examination to identify immediate measures for stabilization.

Diagnostic Studies

• Pulse oximetry, continuous cardiac monitoring, ECG, capillary glucose measurement.
• Serum acetaminophen, ASA levels
• Consider extended toxicology screen.

Differentiating CCB vs. Beta-Blocker Overdose

• ECG findings: PR interval prolongation and Bradydysrhythmia suggest CCB poisoning.
• Hyperglycemia in non-diabetic patients may indicate CCB overdose

Approach to CCB Overdose

• Initial resuscitation and stabilization
• ABC approach
• Consult Poison Control Center
• Empiric use of glucagon, IV fluids, and vasopressors
• Consideration of orogastric lavage and activated charcoal

Specific Medical Therapies

• Vasopressors: norepinephrine/epinephrine infusion
• Atropine for bradycardia
• IV calcium salts to overcome cardiovascular effects
• High-dose insulin and dextrose for myocardial function
• Investigational therapies: methylene blue, lipid emulsion

Procedures

• Transvenous pacemaker placement if needed
• ECMO in refractory hypotension

Key Takeaways

• Hypotension and bradycardia indicate life-threatening toxidromes.
• Differential includes CCB, BB, digoxin, clonidine, and CNS depressants.
• Stepwise approach includes close monitoring of ABCs and specific medical therapies.

Thank you for listening to PICU Doc On Call. We would love for you to share your feedback, subscribe, and review our podcast.

Visit picudoconcall.org for more information and resources.

Stay tuned for our next episode!

References

• Fuhrman & Zimmerman - Textbook of Pediatric Critical Care Chapter 125 and 126.
• St-Onge M et al. Treatment for calcium channel blocker poisoning: a systematic review.
• DeRoos F. Calcium channel blockers. In: Goldfrank's Toxicologic Emergencies, 8th edition.

Hosts:

• Pradip Kamat, Children’s Healthcare of Atlanta/Emory University School of Medicine
• Rahul Damania, Cleveland Clinic Children’s Hospital

Introduction

Today, we discuss the case of an 8-month-old infant with severe bronchospasm and abnormal blood gas. We'll delve into the epidemiology, pathophysiology, and evidence-based management of acute bronchiolitis.

Case Summary

An 8-month-old infant presented to the ER with decreased alertness following worsening work of breathing, preceded by URI symptoms. The infant was intubated and transferred to the PICU, testing positive for RSV. Initial blood gas showed 6.8/125/-4, and CXR revealed massive hyperinflation. Vitals: HR 180, BP 75/45, SPO2 92% on 100% FIO2, RR 12 (prior to intubation), now around 16 on the ventilator, afebrile.

Discussion Points

• Etiology & Pathogenesis: Bronchiolitis is primarily caused by RSV, with other viruses and bacteria playing a role. RSV bronchiolitis is the most common cause of hospitalization in infants, particularly in winter months. Immuno-pathology involves an unbalanced immune response and can lead to various extra-pulmonary manifestations.
• Diagnosis: Diagnosis is clinical, based on history and examination. Key signs include upper respiratory symptoms followed by lower respiratory distress. Blood gas, chest radiography, and viral testing are generally not recommended unless warranted by severe symptoms or clinical deterioration.
• Management Framework: For patients requiring PICU admission, focus on oxygenation and hydration. High-flow therapy and nasal continuous positive airway pressure (CPAP) can be used. Hydration and feeding support are crucial. Antibiotics, steroids, and bronchodilators are generally not recommended. Mechanical ventilation and ECMO may be necessary in severe cases.
• Immunoprophylaxis & Nosocomial Infection Prevention: Palivizumab and nirsevimab are used for RSV prevention in high-risk infants. Strict infection control measures, including hand hygiene and isolation, are essential to prevent nosocomial infections.

Conclusion

RSV bronchiolitis is a common and potentially severe respiratory illness in infants. Management focuses on supportive care, with a careful balance between oxygenation and hydration. Immunoprophylaxis and infection control are crucial in preventing the spread of the virus.

Thank you for listening to our episode on acute bronchiolitis. Please subscribe, share your feedback, and visit our website at picudoconcall.org for more resources. Stay tuned for our next episode!

References

Rogers - Textbook of Pediatric Critical Care Chapter 49: Pneumonia and Bronchiolitis. De Carvalho et al. page 797-823

Reference 1: Dalziel, Stuart R; Haskell, Libby; O'Brien, Sharon; Borland, Meredith L; Plint, Amy C; Babl, Franz E; Oakley, Ed. Bronchiolitis. The Lancet. , 2022, Vol.400(10349), p.392-406. DOI: 10.1016/S0140-6736(22)01016-9; PMID: 35785792

Reference 2: Schroeder AR, Destino LA, Ip W, Vukin E, Brooks R, Stoddard G, Coon ER. Day of Illness and Outcomes in Bronchiolitis Hospitalizations. Pediatrics. 2020 Nov;146(5):e20201537. doi: 10.1542/peds.2020-1537. PMID: 33093138.

Hosts:

• Pradip Kamat, Children’s Healthcare of Atlanta/Emory University School of Medicine
• Rahul Damania, Cleveland Clinic Children’s Hospital

Case Introduction:

• 6-year-old patient admitted to PICU with severe pneumonia complicated by pediatric Acute Respiratory Distress Syndrome (pARDS).
• Presented with respiratory distress, hypoxemia, and significant respiratory acidosis.
• Required intubation and mechanical ventilation.
• Despite initial interventions, condition remained precarious with persistent hypercapnia.

Physiology Concept: Dead Space

• Defined as the volume of air that does not participate in gas exchange.
• Consists of anatomic dead space (large airways) and physiologic dead space (alveoli).
• Physiologic dead space reflects ventilation-perfusion mismatch.

Pathological Dead Space:

• Occurs due to conditions disrupting pulmonary blood flow or ventilation.
• Common in conditions like pulmonary embolism, severe pneumonia, or ARDS.

Clinical Implications:

• Increased dead space fraction (DSF) in PARDS is a prognostic factor linked to severity and mortality.
• Elevated DSF indicates worse lung injury and inefficient gas exchange.
• DSF can be calculated using the formula: DSF = (PaCO2 – PetCO2) / PaCO2.

Practical Management:

• Optimize Mechanical Ventilation
• Enhance Perfusion
• Consider Positioning (e.g., prone positioning)

Summary of Physiology Concepts:

• Bohr equation for physiologic dead space.
• Importance of lung-protective ventilation strategies.
• Monitoring and trending dead space fraction.
• Strategies to improve airway patency and mucociliary clearance.

Connect with us!

• PICU Doc on Call provides concise explanations of critical concepts in pediatric intensive care.
• Feedback, subscriptions, and reviews are encouraged.
• Visit picudoconcall.org for episodes and Doc on Call infographics.
• Hosted by Dr. Pradip Kamat and Dr. Rahul Damania.

Reference:

• Yehya N, Bhalla AK, Thomas NJ, Khemani RG. Alveolar Dead Space Fraction Discriminates Mortality in Pediatric Acute Respiratory Distress Syndrome. Pediatr Crit Care Med. 2016 Feb;17(2):101-9. doi: 10.1097/PCC.0000000000000613. PMID: 26669646; PMCID: PMC4740261.

Today's episode promises an insightful exploration into a unique case centered on retropharyngeal abscess in the PICU, offering a comprehensive analysis of its clinical manifestations, pathophysiology, diagnostic strategies, and evidence-based management approaches.

Today, we unravel the layers of a compelling case involving a 9-month-old with a retropharyngeal abscess, delving into the intricacies of its diagnosis, management, and the critical role played by PICU specialists. Join us as we navigate through the clinical landscape of RPA, providing not only a detailed analysis of the presented case but also valuable takeaways for professionals in the field and those aspiring to enter the world of pediatric intensive care. Welcome to PICU Doc On Call – where MED-ED meets the real challenges of the PICU.

• Patient: 9-month-old male with rapid symptom onset, left neck swelling, fever, noisy breathing, and decreased oral intake.
• Initial presentation: Left neck swelling, limited neck mobility, and deteriorating condition.
• Imaging: Neck X-ray and CT scan with IV contrast confirmed Retropharyngeal Abscess (RPA).
• Management: High-flow nasal cannula, intravenous antibiotics, and consultation with ENT. PICU admission for comprehensive care.

• Rapid Symptom Onset
• Neck Swelling & Drooling
• Limited Neck Mobility

• A previously healthy 9-month-old male with a recent upper respiratory infection, presenting with rapid-onset left neck swelling, fever, and respiratory distress. Imaging suggestive of a Retropharyngeal Abscess, requiring urgent PICU management for airway protection and antibiotic therapy.

• Anatomy of retropharyngeal space
• Rapid communication of infections via lymph nodes
• Infection sources: dental issues, trauma, localized infections (e.g., otitis, URI)

• Airway compromise and posterior mediastinitis
• Progression from cellulitis to abscess
• Microbial suspects: Group A Streptococcus, anaerobes, Staphylococcus aureus, Haemophilus influenza, Klebsiella, Mycobacterium avium-intracellulare

• Seen predominantly in children aged 3-4 years
• Non-specific symptoms in the acute setting
• Pronounced symptoms in PICU: neck pain, stiffness, torticollis, muffled voice, stridor, respiratory distress

• Thorough history and physical examination
• CT scan with contrast as the gold standard
• Blood culture, CRP, and procalcitonin for infection severity

• Limited neck mobility is the most specific physical exam finding
• Younger age and signs of airway obstruction indicate a complicated course

• Antibiotic therapy: Up to 50% cases can be treated with IV antibiotics
• Surgical drainage may be needed if no improvement or persistent respiratory distress
• Duration of therapy: 10 to 14 days
• Controversial use of steroids for reducing airway swelling

• Upper airway obstruction, aspiration pneumonia, internal jugular thrombosis, carotid artery sheath rupture
• Mediastinitis: severe inflammation, infection of mediastinal tissues

• Respiratory viral panel: RSV, adenovirus, rhino/enterovirus
• Intubation due to worsening respiratory distress
• Incision and drainage (I&D) by ENT
• Cultures grew MRSA
• Extubation after air leak detection; discharged on oral Clindamycin

• Maintain a low threshold for suspecting RPA
• Initiate broad-spectrum antibiotics early
• Prioritize airway assessment and intervene early in cases of worsening upper airway obstruction or hypoxia
• Consider surgical drainage for non-responders, escalating respiratory distress, or immunocompromised patients

• Emphasize the critical nature of RPA in children and the importance of early intervention.
• Complications include upper airway obstruction, aspiration pneumonia, and potential vascular complications.

• Villanueva-Fernández E, et al. (2022) Role of steroids in conservative treatment of parapharyngeal and retropharyngeal abscess in children. Eur Arch Otorhinolaryngol.
• Akhavan M. (2021) Ear, Nose, Throat: Beyond Pharyngitis: Retropharyngeal Abscess, Peritonsillar Abscess, Epiglottitis, Bacterial Tracheitis, and Postoperative Tonsillectomy. Emerg Med Clin North Am.
• Reilly BK, Reilly JS. (2012) Retropharyngeal abscess: diagnosis and treatment update. Infect Disord Drug Targets.

Today, Dr. Pradip Kamat (Children’s Healthcare of Atlanta/Emory University School of Medicine) and Dr. Rahul Damania (Cleveland Clinic Children’s Hospital), are excited to speak with Matthew Kirschen, MD, PhD, FAAN, FNCS, regarding a very sensitive topic involving pediatric brain death guidelines published in 'Neurology' in October 2023. Dr. Matthew Kirschen, a leader in pediatric neurocritical care and one of the authors of the new guidelines.

Guest Introduction:

Dr. Matthew Kirschen is an Assistant Professor of Anesthesiology and Critical Care Medicine, Pediatrics, and Neurology at the Children's Hospital of Philadelphia. A proud alumnus of Brandeis University and Stanford, where he secured both his MD and PhD in neuroscience. Dr. Kirschen’s journey includes a residency at Stanford followed by a unique dual fellowship in neurology and pediatric critical care at CHOP. Notably, he's among the rare professionals dual-boarded in both PCCM and Neurology.

Dr. Kirschen’s tireless endeavors in pediatric neuro-critical care, especially his work on multimodal neuro-monitoring to detect and prevent brain injuries in critically ill children, have garnered significant attention. His expertise also extends to predicting recovery post-severe brain injuries. Pertinent to today's discussion, Dr. Kirschen has displayed a keen interest in the precise diagnosis of brain death and proudly stands as one of the authors of the new guidelines on the topic of Pediatric and Adult Brain death/death by neurologic criteria.

Discussion:

1. Understanding Brain Death Criteria:

• Brain Death/Death by Neurologic Criteria (BD/DNC) declared with permanent cessation of all brain functions, including brainstem
• Important considerations before BD/DNC determination:
• No evaluation in infants < 37 weeks corrected gestational age
• Absence of coma, intact brainstem reflexes, and spontaneous breathing inconsistent with BD/DNC

2. Who Can Perform BD/DNC Evaluations:

• Attending clinicians must be credentialed and trained in BD/DNC evaluation.
• Two attending clinicians are needed for evaluation, with exceptions for advanced practice providers.

3. Prerequisites for BD/DNC Determination:

• Importance of identifying the etiology of BD/DNC to avoid reversible processes
• Observation periods based on age and type of brain injury
• Maintaining core body temperature before evaluation

4. Blood Pressure Management:

• Hypotension can lead to impermanent coma; clinicians should manage with fluids or vasopressors.
• Specific blood pressure targets for different ECMO support types

5. Medication Considerations:

• Excluding medications affecting CNS function before BD/DNC evaluation
• Recommendations for drug level monitoring and metabolic derangement exclusion

6. Performing the BD/DNC Neurologic Examination:

• Two independent examinations by different clinicians with a minimum 12-hour interval
• Central components including assessing irreversible coma and brainstem reflexes

7. Apnea Testing:

• Two apnea tests after each neurologic examination
• Procedures, complications, and baseline PCO2 and pH considerations

8. Ancillary Tests:

• BD/DNC remains a clinical evaluation; ancillary tests are used in specific circumstances.
• Conditions and circumstances for using or not using ancillary tests

9. Case Presentation and Family Communication:

• Real-life case presented and discussed following the new AAN guidelines.
• No need for consent before evaluation; communication with the family emphasized.
• Maintaining transparency and involvement in the BD/DNC process

10. Public Trust in BD/DNC:

• Building trust through education, transparency, public involvement, and ethical considerations
• Continuous improvement, professional collaboration, and legal frameworks

We welcome you to share your feedback, subscribe & place a review on our podcast! Please visit our website picudoconcall.org which showcases our episodes as well as our Doc on Call management cards. PICU Doc on Call is co-hosted by Dr. Pradip Kamat and Dr. Rahul Damania. Stay tuned for our next episode! Thank you!

References:

• Greer D, Kirschen MP et al. Pediatric and Adult Brain Death/Death by Neurologic Criteria Consensus Guideline Report of the AAN Guidelines Subcommittee, AAP, CNS, and SCCM. Neurology 2023; 101:1-21. doi:10.1212/WNL.0000000000207740
• Pediatric Neurocritical Care Educational Series - Lecture_ Brain Death 2023 Guidelines

Today’s case presentation involves a 2-year-old girl who was previously healthy and was admitted to the Pediatric Intensive Care Unit (PICU) for acute respiratory distress characterized by increased work of breathing and wheezing.

A 2-year-old girl with acute respiratory distress due to RSV infection

• Presented with increased work of breathing, wheezing, and no fever
• Started on High Flow Nasal Cannula (HFNC) therapy in the PICU

Key Elements:

• Prodrome of URI symptoms
• Increased respiratory effort (nasal flaring, intercostal retractions, decreased lung base air entry)
• HFNC improved the work of breathing and oxygen saturation

Washout of Nasopharyngeal Dead Space:

• HFNC clears nasopharyngeal dead space, improving oxygen efficiency.
• Reduces re-breathing of CO2 from the anatomical dead space.
• Enhances ventilation efficiency and oxygenation.

Reduction in Upper Airway Resistance:

• HFNC reduces resistance in the upper airway.
• Delivers rapid gas flow matching or exceeding natural inhalation rate.
• Eases breathing, especially in neonates and infants with narrow airways.

Optimal Conditioning of Gas:

• HFNC delivers heated and humidified oxygen, matching the body's conditions.
• Reduces energy expenditure and risk of airway irritation
• More comfortable and effective compared to cold, dry air delivery

• HFNC generates minimal and variable PEEP.
• Amount of PEEP depends on factors like flow rate and cannula size
• Not as high or consistent as other respiratory support devices

• A 2022 CHEST study by Khemani et al. on children with bronchiolitis challenged the conventional understanding of HFNC's mechanisms.
• HFNC primarily reduces breathing effort but does not consistently increase lung volume (EELV) or tidal volume (VT).
• Reduction in the pressure rate product (PRP) indicates decreased breathing effort, but not significant alterations in EELV or VT.

• HR, RR, and SpO2 are key indicators of HFNC efficacy.
• HR and RR should approach normal ranges for the child's age.
• Improvement in SpO2 levels while maintaining or reducing FiO2 indicates a positive response.

• HFNC is a valuable tool in pediatric care for alleviating respiratory distress.
• Not a one-size-fits-all solution; vigilant monitoring and reassessment are crucial
• Recognizing HFNC's mechanisms allows for optimized bedside application.

Closing Remarks:

• Subscribe, share feedback, and leave a review on the podcast.
• Visit picudoconcall.org for more episodes and management cards.
• Hosted by Dr. Pradip Kamat and Dr. Rahul Damania

Miller AG, Gentle MA, Tyler LM, Napolitano N. High-Flow Nasal Cannula in Pediatric Patients: A Survey of Clinical Practice. Respir Care 2018; 63:894.

Wraight TI, Ganu SS. High-flow nasal cannula use in a pediatric intensive care unit over 3 years. Crit Care Resusc 2015; 17:197.

Hutchings FA, Hilliard TN, Davis PJ. Heated humidified high-flow nasal cannula therapy in children. Arch Dis Child 2015; 100:571.

Lee JH, Rehder KJ, Williford L, et al. Use of high flow nasal cannula in critically ill infants, children, and adults: a critical review of the literature. Intensive Care Med 2013; 39:247.

Wing R, James C, Maranda LS, Armsby CC. Use of high-flow nasal cannula support in the emergency department reduces the need for intubation in pediatric acute respiratory insufficiency. Pediatr Emerg Care 2012; 28:1117.

Bressan S, Balzani M, Krauss B, et al. High-flow nasal cannula oxygen for bronchiolitis in a pediatric ward: a pilot study. Eur J Pediatr 2013; 172:1649.

Mayfield S, Bogossian F, O'Malley L, Schibler A. High-flow nasal cannula oxygen therapy for infants with bronchiolitis: pilot study. J Paediatr Child Health 2014; 50:373.

Kelly GS, Simon HK, Sturm JJ. High-flow nasal cannula use in children with respiratory distress in the emergency department: predicting the need for subsequent intubation. Pediatr Emerg Care 2013; 29:888.

Welcome to PICU Doc on Call, a podcast dedicated to current and aspiring intensivists. I'm Pradeep Kumar coming to you from Children's Healthcare of Atlanta, Emory University School of Medicine, and I'm Rahul Damania from Cleveland Clinic Children's Hospital. We are two pediatric ICU physicians passionate about all things medical education in the PICU.

Episode Overview: 

PICU.com call focuses on interesting PICU cases and management in the acute care Pediatric setting. In this episode, we discuss the case of an eight-year-old boy with chest pain, fatigue, and shortness of breath. This case presentation by Rahul highlights the complexity of pediatric care in the PICU.

Case Presentation: 

An eight-year-old boy with up-to-date immunizations and no recent travel or pet exposure presented to the PICU with chief complaints of chest pain, fatigue, and decreased oral intake. His history over the preceding two weeks included a diminishing appetite, episodes of vomiting, and shortness of breath.

On examination, he exhibited various cardiac findings, including a hyperdynamic left ventricle, murmurs, and a noted gallop. Abdominal and neurological findings were also concerning. Diagnostic studies revealed an enlarged heart, and sinus tachycardia with left ventricular hypertrophy, and echocardiography confirmed severe valvular and ventricular abnormalities.

Laboratory Findings:

Laboratory findings included elevated BNP, slightly elevated troponin, and elevated inflammatory markers (ESR and CRP). Strep throat culture was negative, but ASO and anti-DNAse B titers were markedly elevated. MRI confirmed multiple punctate infarctions, likely due to valvular heart disease.

Diagnosis: 

Given the complex multisystem presentation, the child was admitted to the PICU for intensive monitoring and comprehensive management of this multisystem pathology. The working diagnosis is rheumatic fever.

The episode is organized into three parts:

• Pathophysiology of Acute Rheumatic Fever
• Approach to Diagnosis and Investigations
• Management and Prevention

Pathophysiology of Acute Rheumatic Fever: 

Acute rheumatic fever is an autoimmune disease initiated by a response to group A strep infection, primarily due to molecular mimicry. The streptococcal M protein has structural similarities with host proteins, leading to organ damage, especially in the heart.

Epidemiology: 

Acute rheumatic fever is most prevalent in low to middle-income areas, affecting over 80% of cases. It mainly affects children between 5 to 14 years of age, and overcrowded households and limited healthcare access increase the risk. Globally, rheumatic heart disease affects millions of people annually and claims many lives.

Jones Criteria for Diagnosis: 

The Jones criteria help diagnose acute rheumatic fever. For a definitive diagnosis, evidence of a preceding group A strep infection is required. Major manifestations include carditis, arthritis, erythema marginatum, subcutaneous nodules, and Sydenham's chorea. Minor criteria include fever, elevated inflammatory markers, prolonged PR interval on EKG, and mild joint issues.

Differentiating Low and High-Risk Populations: 

The criteria differentiate between low and high-risk populations based on the epidemiology of acute rheumatic fever. The presentation of arthritis varies, and the thresholds for fever or inflammatory marker elevation are lower in high-risk populations.

Diagnostic Approach:

Diagnosis includes throat swab, anti-streptolysin O antibody titers, anti-DNAse B titers, CBC with differential, blood cultures, inflammatory markers, EKG, chest X-ray, and echocardiography. Joint analysis may be performed if needed.

Sydenham's Chorea:

Sydenham's chorea is marked by involuntary movements, primarily in the trunk and limbs, and it often resolves within 12 to 15 weeks with treatment.

Management of Acute Rheumatic Fever: 

Management includes eradicating the remaining strep infection, controlling inflammation, and preventing recurrence. Penicillin or amoxicillin is used to treat the infection, while aspirin or NSAIDs are used to manage inflammation. In severe cases, systemic steroids may be considered. Cardiac surgery should be delayed until acute inflammation resolves. Prophylactic antibiotics are used for prevention.

Conclusion: 

Rheumatic fever management requires a holistic approach, encompassing infection control, inflammation management, and long-term prevention. Early recognition, thorough diagnostics, and prophylactic antibiotics play essential roles in managing this condition.

Future Directions: 

Research is needed for early detection using biomarkers and the development of a group A strep vaccine.

Closing Remarks: 

As pediatric intensivists, we play a pivotal role in primary prevention by advocating for awareness and prompt treatment of group A strep infections.

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