Respiratory Failure in the Pediatric Patient Ndidi Musa M.D. Associate Professor of Pediatrics Medical College of Wisconsin Pediatric Cardiac Intensivist Children s Hospital of Wisconsin
Objectives Recognize different types of respiratory failure Pathophysiology Management Adjuncts to respiratory support
Scope of The Problem
Respiratory Failure
Anatomy Upper Airway Humidifies inhaled gases Site of most resistances to airflow Lower Airway Conducting airways (anatomic dead space) Site of gas exchange (Resp bronchioles, alveoli)
Respiratory Failure Inability of the pulmonary system to meet the metabolic needs of the body not always associated with distress Two crucial metabolic roles Ventilation elimination of CO2 byproduct of cellular respiration Oxygenation-delivery to tissues for utilization 3 forms of respiratory failure Hypoxemic Hypercarbic Mixed
Approach to Respiratory Failure Drive issue- patient won t breath CNS (Head injury, Status epilepticus, sedation) Toxin( Drugs) Work issue- patient can t breath because of strength or load Airways (Resistance-UAO, asthma, bronchiolitis) Lungs (Compliance- Pnuemonia) Pump ( Muscle problem- prolonged illness, GBS)
Approach to Respiratory Failure Basic mechanism of hypoxemia Ventilation perfusion mismatch most common Diffusion Alveolar hypoventilation Shunt Intra cardiac Extra cardiac (intra- pulmonary) Hypoxia- arterial O2 sat reduced
Hypoxemic Respiratory Failure Defined as a PaO2 < 60mmHg Hypoxemic hypoxia Arterial oxygen saturation is reduced Anemic hypoxia SaO2 normal but O2 content reduced by low Hgb inadequate O2 carrying capacity Ischemic hypoxia Blood flow to tissue is low Hgb and O2 concentration normal but cardiac output is low(hypovelemia, myocardial insufficiency) Histotoxic hypoxia Tissue unable to utilize O2,(cyanide or CO poison)
Hypercapnic Respiratory Failure Defined as a PaCO2 > 50mmHg Decreased Tidal volume Minute ventilation (volume of air in and out of lung/minute) MV= RR x Tidal volume Shallow breathing, compliance (stiff lungs) airway resistance Decreased Respiratory Rate Drive Increased physiologic dead space Increased carbon dioxide production
Categorization of Respiratory Failure Respiratory distress Increased RR by Severity Increased effort (flaring, retractions, use of accessory muscles) Respiratory Failure Clinical state of inadequate oxygenation ventilation or both End stage of respiratory distress
Respiratory Distress Intrinsic Pulmonary problem Upper airway obstruction Laryngotracheobronchitis Lower airway obstruction Asthma Bronciolitis Lung parenchyma Pneumonia Pulmonary edema Systemic problem Malaria Shock Dehydration Anemia Heart disease Renal disease
Causes of Respiratory Distress Wheeze Crackles Asthma Pneumonia Malaria Treat underlying causes Difficulty breathing Pnuemonia -O2,Abx,Fluids Retractions Asthma-Bronchodilators,Fluids Tachypnea Dehydration- Fluids Anemia-Blood Malaria- Antimalarials, fluids, Anaemia Acidosis Blood film Pallor Acidosis Dehydration Sunken eyes Skin Turgor Acidosis Courtesy Dr B Bevins
Management Depends on cause Airway Breathing Circulation
Stabilization Airway Clear (unobstructed for normal breathing) Maintainable (simple measures- head tilt, suction) Not maintainable (Advanced interventions)
Stabilization Breathing Respiratory rate Effort Nasal flaring Retractions Minute ventilation (volume of air in and out of lung/minute) MV= RR x Tidal volume Shallow breathing, stiff lungs or airway resistance Lung sounds Pulse oximetry
Pulse Oximetry The systematic use of pulse oximetry to monitor and treat children in resource-poor developing countries, when coupled with a reliable oxygen supply, improves quality of care and reduces mortality Trevor Duke Annals of Tropical Paediatrics (2009) 29, 165 175
Pulse Oximetry Systematic review of 21 published and unpublished articles 16,000 children with acute lower respiratory infection the median hypoxemia prevalence among 13 studies which included children with WHO-defined severe and very severe pneumonia was 13.3% (9.3 37.5%) 11 20 million children are admitted to hospital each year with Pneumonia, 1.5 2.7 million episodes of hospitalized pneumonia associated with hypoxemia occur in young children globally each year. Annals of Tropical Paediatrics (2009) 29, 165 175
Scatter diagram showing the correlation between the respiratory rate and oxygen saturation. RR> 60 correlated with low SaO 2 Rajesh V T et al. Arch Dis Child 2000;82:46-49 2000 by BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health
Who do you screen? Annals of Tropical Paediatrics (2009) 29, 165 175
Oxygen Availability
Oxygen is an essential medicine: a call for international action Hypoxaemia is commonly associated with mortality in developing countries, yet feasible and costeffective ways to address hypoxaemia receive little or no attention in current global Improving access to oxygen and pulse oximetry health strategies.oxygen treatment has been used in medicine for almost 100 years, but in developing countries most seriously ill newborns, children and adults do not have access to oxygen or the simple test that can detect hypoxaemia. Improving access to oxygen and pulse has demonstrated a reduction in mortality from oximetry has demonstrated a reduction in mortality from childhood pneumonia by up to 35% childhood in high-burden child pneumonia settings. by The up cost-effectiveness to 35% in of highburden interventions, child such pneumonia as new vaccines. In settings. addition to its use The in treating cost- acute an oxygen systems strategy compares favourably with other higher profile child survival respiratory illness, oxygen treatment is required for the optimal management of many other conditions effectiveness in adults and children, of an and oxygen is essential for systems safe surgery, strategy anaesthesia and obstetric care. Oxygen concentrators provide the most consistent and least expensive source of oxygen compares in health facilities favorably where power with supplies other are reliable. higher Oxygen concentrators profile are sustainable child survival in developing country interventions, settings if a systematic such approach as new involving nurses, doctors, technicians and administrators is adopted. Improving oxygen vaccines. systems is an entry point for improving the quality of care. For these broad reasons, and for its vital importance in reducing deaths due to lung disease in 2010: Year of the Lung, oxygen deserves a higher priority on the global health agenda. Keywords oxygen; hypoxaemia; pneumonia; lung disease; health systems HYPOXAEMIA is a major cause of morbidity and mortality associated with acute and chronic lung disease in children and adults. Hypoxaemia is a low level of oxygen in the arterial 2010
Nasal(neonate)C annula Conversion (Gomella-Lange) Flow rate FI02 ¼L 34% ½L 44% ¾L 60% 1L 66% Oxygen Therapy In an adult 1L flow 24% FIO2 FIO2 by 4% for every 1L flow up to 6 L flow (2L 28%) Oxygen concentrators work best with nasal cannulas.
Reality we have to deal with Advantage in developed world
Using The Tools We Have Monitoring allows the recognition of a patient early in distress or early warning signs of respiratory failure. Tools Physical exam Monitor Cardio-respiratory monitor Pulse oximeter
Golden Hour Respiratory Distress Possibly Hours Respiratory Failure Potentially minutes Cardiopulmonary Arrest
Early recognition Early Resuscitation Constant Re-assessment Improved Outcome Triage Respiratory rate Retractions Oxygen saturation Emergency Care Oxygen Antibiotics Airway support Ventilation Respiratory Rate Retractions O2 Saturation
Adjuncts To Respiratory Support Continuous positive airway pressure(cpap) Non Invasive positive pressure ventilation (NPPV or BIPAP)
CPAP or BiPAP Indications Patient who has increased work of breathing despite oxygen support Pneumonia Asthma Gullian barré Syndrome(GBS) Congestive heart failure
Non Invasive Mechanical Ventilation(NPV)
Contraindication of NPV Respiratory arrest Cardiovascular instability Somnolence High risk of aspiration Craniofacial trauma
Non Invasive Mechanical ventilation Advantages Avoids upper airway trauma Leaves airway defenses intact Comfortable Sedation needs less Disadvantages Gastric distention Facial skin necrosis Airleak
Bubble CPAP
Bubble CPAP Low resistance delivery system Large bore tubing Nasal prongs Fit appropriately and prevent leaks Warm humidified gas Suction 3-4 hrs
Bubble CPAP Maintains positive pressure in airway during spontaneous ventilation improves oxygenation Splint the airway, diaphragm Prevents alveolar collapse
Bubble CPAP Monitoring Respiratory CVS GI Thermoregulation
Summary Systematic approach to a patient in respiratory distress Complete assessment and reassessment of the patient Communication - Interdisciplinary team approach Residents Nursing PATIENT Specialist
Team Training building competence to Excellence!
Acknowledgement Slides from Dr Vinay Nardkarni Dr Trevor Duke Dr David Hehir Dr Bill Bevins Dr From Mali