Respiratory Distress National Pediatric Nighttime Curriculum Written by Liane Campbell, MD Lucile Packard Children’s Hospital, Stanford University

Learning Objectives Review the initial assessment of patient in respiratory distress Review management of specific causes of respiratory distress Upper airway obstruction Lower airway obstruction Lung tissue disease Disordered control of breathing Respiratory distress: characterized by signs of increased work of breathing stridor wheezing tachypnea and retractions abnormal pattern of respirations Respiratory distress may be due to: an attempt to improve minute ventilation in response to hypoxemia or hypercarbia disordered control of ventilation such as… respiratory depression from opioid overdose or head injury respiratory stimulation from metabolic acidosis, salicylate overdose, or hyperammonemia.

During a busy night, you get the following page: FYI: Sally, a 2 year old with PNA had a desat to 88% while on 2L NC. Promptly assess the patient to elicit additional important information: such as the duration of the desaturation, her general appearance and mental status, other signs of respiratory distress such as tachypnea, use of accessory muscles, grunting or flaring If the patient is still hypoxic, what can you do to quickly correct the hypoxia? increase the flow of the nasal cannula OR switch to a new delivery device such as a simple face mask While nasal cannulas can deliver up to 6L/min, flow rates greater than 4L/min are irritating to the nares and therefore switching to a simple face mask may be better tolerated) Optimize the patient’s positioning and Suction away secretions, should they be present Consider a non-rebreather face mask with an increased flow or CPAP Call for backup (such as a supervising resident or hospitalist) Consider a trial of albuterol if wheezing is present Once the patient is stabilized, it may be helpful to obtain a new chest x ray to evaluate for worsening pneumonia or development of an effusion that may have contributed to her acute decompensation. What do you do next? What initial management steps would you take?

How do you initially assess a patient in respiratory distress? Stop here. Have group suggest at least two ways they assess patients in respiratory distress. Answers on next slide.

Initial Assesment Rapid assessment Airway Breathing Circulation Quickly determine severity of respiratory condition and stabilize child Respiratory distress can quickly lead to cardiac compromise Airway Support or open airway with jaw thrust Suction and position patient Breathing Provide high concentration oxygen Bag mask ventilation Prepare for intubation Administer medication ie albuterol, epinephrine Circulation Establish vascular access: IV/IO The initial assessment of a child in respiratory distress should be rapid and quickly determine if patient needs emergent interventions and rule out life threatening conditions.

History and Physical Exam Trauma Change in voice Onset of symptoms Associated symptoms Exposures Underlying medical conditions Mental status Position of comfort Nasal flaring Accessory muscle use Respiratory rate and pattern Auscultation for abnormal breath sounds A brief history should be collected initially which should include these important points: A more detailed history can be collected once the child is stabilized When auscultating, listen for: wheezes crackles pleural rub prolonged expiration decreased breath sounds transmitted upper airway sounds

What initial studies would you get for a patient in respiratory distress? Stop here. Have the group suggest two studies they would like to get for a patient in respiratory distress. Answers on the next slide.

Initial studies Pulse oximetry Imaging Labs May be difficult in agitated patient May be falsely decreased in very anemic patients Imaging Chest X Ray Consider in patients with focal lung findings or respiratory distress of a unknown etiology Soft tissue radiograph of lateral neck May identify a retropharyngeal abscess or radiopaque foreign body Labs ABG/VBG Chemistry: calculate anion gap Urine toxicology and glucose if patient has altered mental status Advantages of VBG include less pain to the patient and ability to draw concurrently with other labs A normal venous pH, pCO2, and HCO3 rules out severe acid base abnormalities A venous pH of > 7.25 predicts an arterial pH of > 7.2 in 98% of cases (Conversely, a venous pH of < 7 predicts an arterial pH of < 7.2 in 98% of cases) A venous pCO2 of > 45 mm Hg is predictive of an arterial pCO2 of > 50 mm Hb Venous blood gasses do not allow adequate determination of the arterial concentration of oxgyen (paO2) and is not as useful to quantify oxygen delivery to target tissues

What are some examples of life threatening conditions? Stop here. Have the group suggest three life threatening conditions. Answers on the next slide.

Life threatening conditions Complete upper airway obstruction No effective air movement, speech or cough Respiratory failure Pallor or cyanosis, altered mental status, tachypnea, bradypnea, apnea Tension pneumothorax Absent breath sounds on affected side, tracheal deviation and compromised perfusion Pulmonary embolism Chest pain, tachycardia, tachypnea Cardiac tamponade Apnea, tachycardia, hypotension, respiratory distress

Specific Causes of Respiratory Distress Upper airway obstruction Lower airway obstruction Lung tissue disease Disordered control of breathing

Case 1 8 month old ex-FT girl with 2-3 days of nasal congestion, cough, and sneezing, was RSV+ on admission with mild work of breathing requiring 0.5L O2. As you’re watching the monitors on Short Stay with the nurse at 2am, she’s now 84-89%. What is your diagnosis? What are your next steps? Diagnosis: bronchiolitis Next steps: suction, reposition, increase O2 if needed (on day 3-4 of illness), may trial albuterol

Case 2 4 year old boy admitted to GI service for monitoring and serial AXRs because he ingested a sharp object. He’s tucked in for the night with an AM AXR ordered. But after his dinner, he suddenly becomes stridulous, and starts crying and drooling. Parents just left the room to get dinner. What is your initial evaluation/management? Diagnosis: foreign body Management: STAT chest film, may consult ENT based on findings. The fact that he is crying is a good sign.

Case 3 3 year old girl with 2 days of fever, noisy breathing and loud barking cough tonight. In the ED 3 hrs ago, got one racemic epi neb and a dose of oral steroids. Admitted for observation. Nurse calls now because his breathing is getting noisy at rest and he’s coughing. No respiratory distress. How do you manage him overnight? Diagnosis: croup Management: may give another dose of racemic epinephrine for stridor at rest or respiratory distress

Case 4 Jonathan is a 2 year old with Pompe’s disease who is BiPAP dependent overnight with settings of 18/5 and a backup rate of 18. Over the past few hours, he has had an increase in his oxygen requirement from an FiO2 of 21 to 40% and has spiked to 39.2. What steps do you take to evaluate and manage him overnight? Patients with neuromuscular disorders and dependence on ventilatory support are at increased risk for development of pneumonia due to their underlying restrictive lung disease and propensity to develop atelectasis. In this patient, the new fever and significant increase in his oxygen requirement is suggestive of pneumonia therefore management should include… Obtaining a chest x ray to evaluate for the presence of an infiltrate If an infiltrate is present, antibiotics should be started promptly Anti-pyretics should be given. Obtain a venous blood gas to evaluate for retention of carbon dioxide Adjustment of the patient’s BiPAP based on the results of the blood gas should include: review of prior blood gasses consultation with the team primarily responsible for managing his BiPAP (likely Pulmonology) If the patient continues to worsen, transferring the patient to the PICU may be appropriate.

Upper Airway Obstruction Causes: foreign body, tissue edema, trauma, viral infection, intubation, tongue movement to posterior pharynx with decreased consciousness Symptoms Partial obstruction: noisy inspiration (stridor), choking, gagging or vocal changes Complete obstruction: no audible speech, cry or cough Management Rapidly decide if advanced airway is needed Avoid agitation Suction only if blood or debris are present Reduce airway swelling Inhaled epinephrine Corticosteroids Croup and anaphylaxis require additional management Croup Symptoms: barking cough stridor retractions Treatment: Oral or IM dexamethasone Oxygen Keep NPO Nebulized racemic epinephrine with observation for at least 2 hours after treatment Anaphylaxis Stridor or wheezing Dizziness Vomiting or diarrhea Hives or facial swelling IM/IV epinephrine Albuterol (if bronchospasm is present) Treat hypotension Diphenhydramine Ranitidine Methylprednisolone

Lower Airway Obstruction Bronchiolitis Symptoms: copious nasal secretions, wheezes and crackles in child less than 2 years Management Oral or nasal suctioning Viral studies, CXR, ABG/VBG Trial of nebulized albuterol Asthma Symptoms: wheezing, tachypnea, hypoxia Mild-moderate: oxygen, albuterol, oral corticosteroids Moderate to severe: oxygen, albuterol-ipratropium (Duo-Neb), corticosteroids (IV), magnesium sulfate Impending respiratory failure: oxygen, albuterol-ipratropium, corticosteroids, assisted ventilation (bag-mask ventilation, BiPAP, intubation), adjunctive agents (terbutaline, magnesium sulfate), heliox Assisted ventilation for patients with lower airway obstruction should be at a slow rate with adequate expiratory time to decrease the risk of air trapping and complications with high airway pressure including pneumothorax, gastric distension, regurgitation and aspiration.

Lung Tissue Disease Etiologies of lung tissue disease Infectious pneumonia Aspiration pneumonitis Non-cardiogenic pulmonary edema (ARDS) Cardiogenic pulmonary edema (ARDS) Consider positive expiratory pressure (CPAP, BiPAP or mechanical ventilation with PEEP) if hypoxemia is refractory to high concentrations of oxygen For more information regarding specific etiologies of lung tissue disease: Infectious pneumonia Symptoms: fever, tachypnea, hypoxemia, increased work of breathing, crackles or decreased breath sounds Management: Ancillary testing: ABG/VBG, CXR, viral studies, CBC, BCx Antibiotics to treat gram + organisms, consider macrolide coverage Albuterol if wheezing Reduce temperature if febrile Aspiration pneumonia Symptoms: coughing or gagging associated with feeding, more common in children with abnormal neurologic status Management Respiratory support and antibiotics if infiltrate is present on CXR Non-cardiogenic pulmonary edema (ARDS) Symptoms: pulmonary or systemic insult to the alveolar-capillary unit with release of inflammatory mediators Correction of hypoxemia Intubate if hypoxemia is refractory to high inspired oxygen concentrations Cardiogenic pulmonary edema Symptoms: fluid accumulation in the lung interstitium due to elevated pulmonary capillary pressure Ventilatory support Support cardiovascular function

Disordered Control of Breathing Abnormal respiratory pattern produces inadequate minute ventilation Altered level of consciousness Elevated intracranial pressure Cushing’s triad Poisoning or drug overdose Administer specific antidote if available Hyperammonemia Metabolic acidosis Neuromuscular disease Restrictive lung disease => atelectasis, chronic pulmonary insufficiency, respiratory failure Support oxygenation and ventilation while treating the underlying problem Disordered control of breathing can be due to elevation of intracranial pressure or depressed level of consciousness due to CNS infection, seizures, metabolic disorders, poisoning or drug overdose.

Take Home Points The initial assessment of a patient in respiratory distress should be rapid and focused on quickly determining the severity of respiratory distress and need for emergent interventions Specific causes of respiratory distress can be categorized as upper and lower airway obstruction, lung tissue disease and disordered control of breathing and require specific interventions

Questions 1. Which of the following are NOT symptoms of an upper airway obstruction? Gagging Changes in voice quality Noisy inspiration (stridor) No audible speech, crying or cough Crackles on auscultation (answers are in speaker’s notes) 5. Crackles on auscultation   Gagging, choking, changes in voice quality and noisy inspiration are all symptoms of a partial upper airway obstruction. Patients with complete upper airway obstruction may have no audible speech, crying or coughing. Patients who present with both partial and complete airway obstruction should be managed quickly and to rapidly determine whether or not an advanced airway is needed. Agitation should be avoided and suctioning should only be performed if blood or debris is present. Airway swelling can be reduced with inhaled epinephrine and corticosteroids. Crackles on auscultation are associated with lower airway disease, and conditions such as pneumonia or atelectasis.

Keeping the patient NPO Nebulized racemic epinephrine Dexamethasone 2. During a busy evening shift, you admit a 2 year old male who presents with a barking cough, stridor at rest, and moderate retractions. He is alert and oriented and calms with his mother. His vital signs on admission are temperature 38.5, heart rate 165, respiratory rate 65, blood pressure 90/45 and oxygen saturation of 92%. Which of the following should NOT be included in your initial management? Oxygen Keeping the patient NPO Nebulized racemic epinephrine Dexamethasone Nebulized albuterol 5. Nebulized albuterol   The patient described in the scenario has moderate croup, as evidenced by his symptoms of barking cough, stridor at rest and moderate retractions. The management of moderate croup should include oxygen, nebulized racemic epinephrine with monitoring for 2 hours after this treatment is given and oral or IV dexamethasone. The patient should be kept NPO and closely monitored for deterioration and respiratory failure. Albuterol is used to treat lower airway obstruction due to bronchospasm and is unlikely to be helpful in this setting.

3. What is the first medication that should be given to a patient with anaphylaxis and respiratory distress? Diphenhydramine Ranitidine Solumedrol Epinephrine Albuterol Epinephrine is the drug of choice for treatment of anaphylaxis and should be immediately given intramuscularly at a dose of 0.01mg/kg (of a 1 mg/mL or 1:1000 dilution). Epinephrine is the only medication that prevents or reverses upper and lower airway obstruction and prevents or reverses cardiovascular collapse. Diphenhydramine, ranitidine and solumedrol are adjunctive treatments for anaphylaxis and should not be given before epinephrine. Albuterol may be useful in relieving symptoms of bronchospasm not relieved by administration of epinephrine, but is also an adjunctive treatment.

4. While on call in January, you admit a 10 month old prev 4. While on call in January, you admit a 10 month old prev. healthy female who presents with cough, nasal congestion and fevers of 2 days and 1 day of tachypnea. She is fully immunized. On exam, her temp is 39.2, HR 130, RR 55 and O2 sat 93% on RA. Her lung exam reveals diffuse crackles and wheezes at the bases as well as moderate subcostal retractions, but no flaring, grunting or head bobbing. Which diagnostic test is most likely to demonstrate the cause of her respiratory distress? Chest X Ray Nasopharyngeal swab for viral panel Blood culture Urinalysis CBC with differential 2. Nasopharyngeal swab for viral panel The infant described in the vignette has clinical bronchiolitis and a nasopharyngeal swab for viral panel is most likely to reveal the cause of her respiratory distress. Chest X rays are not routinely indicated for patients with clinical bronchiolitis without significant hypoxia or respiratory distress and may lead to inappropriate administration of antibiotics. A blood culture and CBC with differential are indicated if the patient is under 3 months of age and has been febrile but are not likely to demonstrate the cause of the patient’s respiratory distress. Finally, a catheterized urinalysis and urine culture are recommended as this patient is under 12 months and is febrile as there is a relatively high incidence of urinary tract infection in association with RSV, but will also likely not demonstrate the cause of her distress.

5. When performing an initial assessment of a patient in respiratory distress, the history should include all of the following elements EXCEPT: Change in the quality of voice Underlying medical conditions Recent episodes of trauma Previous episodes of respiratory distress Detailed family history 5. Detailed family history   When performing an initial assessment of a patient in respiratory distress, the history should be focused and rapid with the goal of quickly determining the severity of the patient’s respiratory distress and need for emergent interventions. In pediatric patients, respiratory distress can quickly lead to cardiac compromise. Obtaining a detailed family history is unlikely to impact the initial management of a patient in respiratory distress, but clearly, once the patient is stabilized, more history can be obtained.

References Albisett, M. Pathogenesis and clinical manifestations of venous thrombosis and thromboembolism in infants and children. June 2010. UpToDate. Bailey, P. Oxygen delivery systems for infants, children and adults. May 2010. UpToDate. Ralston, M.et. al. Pediatric Advanced Life Support Provider Manual. 2006. American Heart Association. Sherman, S.C. and Schindlbeck, M. When is venous blood gas analysis enough? Emerg Med 38(12):44-48, 2006 Simons, F. Anaphylaxis: Rapid recognition and treatment. September 2010. UpToDate. Weiner, D. Emergent evaluation of acute respiratory distress in children. May 2010. UpToDate.