Anna- jaques ems rounds

1. Welcome once again! Anna-jaques ems rounds

2. Domenic Martinello, MD EMS Medical Director Asst Director, Emergency Medicine Anna-Jaques Hospital DISEASES OF THE PAEDIATRIC AIRWAY and ventilator management

3. Tonight's Agenda • Old Business • New Business • Borrowed Business • Blue Business • Case • Diseases of the paediatric airway • Ventilator management • Summary

4. Old Business • AJH Level III Trauma Certification • Still in place! • Still the area’s only Level III center • STEMI changes • Exeter and Nashua have been added to EMS STEMI destinations • New signage outside to help get people to the ER • Hopefully no more ambulance calls to the parking lot!

5. New Business • EMS EKG Exams • Will be out soon… start preparing! • Anyone have other new business?

6. Borrowed/Blue Business • …That was a joke.

7. What time is it? Clinical Case Time!

8. In The Beginning • Your ambulance is dispatched on Monday morning at 0500 to a private home with a chief complaint of a teenage male choking, unknown additional information • Thoughts?

9. Arrival • You arrive and meet patient’s father waiting outside, he appears calm but hurries you into the home stating the patient is upstairs. Mother is with patient. • You ascertain he is awake, alert, oriented, but feels like his throat is swelling • Thoughts?

10. Patient Encounter • You arrive to find a 14 year old male sitting on his bed spitting into a cup • He can talk but appears uncomfortable with any attempt to speak or swallow • Has not eaten anything this morning • Poor diet last 3-4 days secondary to sore throat, some liquids yesterday • Feels weak, states throat feels “tight” • Now what?

11. Exam • Patient is awake and alert, spitting into cup • VS: BP 108/58, HR 118, RR 20 and unlaboured, pO2 99% (RA), t103.2F • Breath sounds normal with some mild transmitted upper airway sounds • Hear sounds rapid, skin warm, abdomen nontender, skin shows no rash • How would you examine the airway?

12. This is your view:

13. So… • Differential Dx • Treatment Plan • “Safety Net”

14. Academic Discussion 1 Diseases of the paediatricupper airway system

15. Anatomy • Begins at mouth/nose and ends at the transition from segmental bronchi to bronchioles (has to do with histophysiology of these areas)

16. Types of problems • Space occupying lesions • Tumor (benign and malignant) • Abscess • Oedema • Haematoma • Congenital Disorders • Acquired infections and conditions • Allergic (discussed in previous lectures) • Neurological (functional problems outside the scope of this lecture)

17. Space Occupying Lesions • Tumours, Oedema, and Haematoma • Not much that can be done in the field (or in the ER!) • ANY manipulation of the airway can be a catastrophe • Some of these can be EXTREMELY rapid in their expansion • Haematoma from neck wounds, oedema from anaphylaxis • If it is technically possibly you should intubate EARLY (especially with expanding lesions). • Consider need for crichothyroidotomy EARLY (may be lifesaving!)

18. Pharyngeal Abscesses • Peritonsilar Abscess (PTA) • Also known as “quinsy” • No idea why • Retropharyngeal Abscess (RPA) • Ludwig’s Angina (angina ludovici) • Angina = Greek for “choking”, or the sensation of choking. • Complication of above • Associated with piercings of the frenulum

19. PTA • Abscess formation in the peritonsilar area • Seen in children and adults, unlike “strep throat” which usually affects children > adults. • Usually the result of untreated or partially treated pharyngitis/tonsilitis • Bacteria accesses the loose connective tissue lateral to the tonsils where there is a virtual space • Arises 2-8 days after initial infection • Signs/Symptoms: unilateral sore throat, fevers, tender lymph nodes (usually isolated to affected side), “hot potato voice”. Usually easily visible on physical exam. • May progress to airway compromise, Ludwig’s Angina, mediastinitis, sepsis • Treatment is combination of antibiotics and drainage (needle vs surgical I&D) • Most organisms are penicillin resistant

20. RPA • Abscess in the posteriour pharyngeal wall • Tends to affect infants and children only • Is a Deep Tissue Space infection, making it hard to nearly impossible to diagnose on physical exam • Making it harder is that it is a rather uncommon condition • S/S: Stiff neck, difficulty swallowing, airway compromise, fever, sore throat, stridor, tenderness to the anteriour neck • Caused by any upper respiratory infections as well as punctures from foreign body • Another reason to never hold a sharp object in your mouth! • Complications: Airway Compromise, sepsis • Diagnosis: XR (80% sensitive), CT (gold standard) • Treatment: Surgical Drainage and IV antibiotics • Drainage universally done in the OR

21. RPA • Xray:

22. Ludwig’s Angina (angina ludovici) • Life threatening submandibular space infection • Usually not an abscess, usually cellulitis • Dental Infections cause about 80% of cases • Usually seen in immune compromised patients • Uncommon complication of piercings to the frenulum • S/S: fever, choking sensation, airway collapse, boggy and/or tender submental space, elevation of the base of the tongue, trismus • Treatment: high dose IV antibiotics, nasotracheal intubation or tracheostomy

23. Tracheal Congenital Disorders • Subglottic Stenosis • Note: may also be an acquired disease! • Pharyngomalacia, Tracheomalacia, and Bronchomalacia • Tracheoesophageal fistula

24. Subglottic Stenosis • Congenital or acquired narrowing of the trachea just below the vocal cords (glottis) • Acquired forms often happen in children when a cuffed tube is used and there is too much pressure in the cuff • Emergency Treatment: • Small caliber ETT inserted through stenotic region • Definitive Tx: Surgical revision by ENT

25. Subglottic Stenosis • AP neck XR • Direct View:

26. Pharyngo-, Tracheo-, and Bronchomalacia • Essentially all are congenital (rarely acquired from chronic inflammatory disease) diseases which share a common pathology of weak, floppy, poorly developed cartilage and connective tissue • The affected structure becomes hypermobile and also lacks the support that these structures have, leading to airway compromise • Typically time is the only treatment needed though medical management with CPAP/BiPAP or surgical management (transplants, implants, supportive scaffolding, etc) when disease is severe • Condition can make intubation difficult due to floppy pharynx, epiglottis, and other structures which may obscure view • Emergency treatment is intubation and mechanical positive pressure ventilation

27. Tracheoesophageal Fistula (TEF) • Congenital disease where there is improper development of the trachea and oesophagus. • These structures actually start as one “tube” embryonically and divides into 2 later • For those so inclined they are derived from the foregut and separate about weeks 4-5 • Incomplete division causes fistula, blind pockets (atresia), or combination of both • Tracheal atresia is inconsistent with fetal survival so oesophageal atresia is the only form discussed

28. TEF • Different types:

29. TEF • Why is this important? • Typically leads to poor feeding • Can be a cause of chronic cough • Aspiration can cause pneumonitis and sudden respiratory failure • Treatment: Intubation may be necessary (and depending on fistula location may be temporizing) • Surgery for definitive care

30. Acquired Tracheal Disorders • Croup • Epiglottitis • Foreign Body

31. Croup • Aka laryngotracheobronchitis • Viral infection (usually) which causes swelling and decreased caliber of the respiratory passages from the larynx through the bronchi • May also be caused by diptheria, strep, staph, and haemophilus infections • S/S: cough, fever, stridor, classic “Barking” cough • Seen mostly between 6months and 6 years • Almost never seen in teenagers or adults • Dx: Diagnosed clinically, no testing needed • Can see “Steeple Sign” on AP Neck Xray • Tx: Intubation for severe episodes • Racemic epinephrine can decrease intubations • Steroids often used with good effect • Heliox can also be used to temporize patients

32. Epiglottitis • Bacterial infection of the epiglottis (and occasionally surrounding tissues) which causes swelling, oedema, and airway compromise • Fun fact: the epiglottis has taste buds (why?) • Is much more rare now that we vaccinate for haemophilisinfluenzae • S/S: Difficulty swallowing, dyspnea, stridor, acute obstruction • Tx: Antibiotics, Airway Management in the OR whenever possible. May require trach/crich • Note: If you suspect epiglottitis in a patient it is IMPERATIVE you DO NOT attempt any visualization of the airway as the SLIGHTEST stimulation can cause airway collapse.

33. Foreign Body • Management of airway foreign bodies is broken down into partial and complete obstructions • Complete obstructions are a life threatening emergency that necessitates the Heimlich maneuver in a conscious patient, or emergent management for unconscious patients • Consider laryngoscopy in unconscious patients and attempt removal if possible • Often a patient’s airway muscles will relax once unconscious making a formerly stuck object much more easily retreived • If not possible patients require IMMEDIATE crichothyroidotomy • Conscious patients with a patent airway should be calmed and transported as high priority with equipment ready for emergency management • Foreign bodies below the cricoid membrane will NOT improve with an emergent crichothyroidotomy • Require bronchoscopy • May respond to Heimlich maneuver

34. Questions? • There are FAR more conditions than we could ever cover in an hour • These are the most prevalent and important • Next section will discuss what happens once you manage the airway… ventilation!

35. Academic Discussion 2 Paediatric ventilator management

36. Just so you know This is a prior lecture, don’t mind the format change 

37. Pediatric Vent Management Domenic Martinello, MD Asst. Director of Emergency Medicine Anna Jaques Hospital, Newburyport, MA

38. Purpose • With the new requirements by OEMS/MADPH stating all intubated patients undergoing interfacility transfer have to be on a ventilator, a protocol needs to be developed • Also, many of us have very rare opportunity to actually put a pediatric patient on a vent, so a refresher always helps!

39. Quick Primer to Terms: • Tidal Volume (TV) = volume of each breath • Rate = breaths per minute • Flow = volume/time • Resistance = impedance to flow • Compliance = elasticity of lungs • How “easily” the lungs inflate • PIP = Positive Inspiratory Pressure • Maximum airway pressure during inspiration • PS = Pressure Support, the amount of pressure applied to the patient during spontaneous inspiration • CPAP = Pressure applied to patient during ALL phases of the respiratory cycle • I-Time (Inspiration time) = time for the complete inspiration phase of the ventilator cycle

40. Modes • VC (Volume Control) • PC (Pressure Control) • PS / CPAP (Pressure Support/CPAP) • BiPAP (Bi Level CPAP) • PRVC (Pressure Regulated Volume Control) • SIMV (Synchronized Intermittent Mandatory Ventilation) • Others outside the scope of this lecture: • APRV (Airway Pressure Release Ventilation) • High Frequency / Oscillatory Ventilation

41. Volume Control (VC) • Ventilator delivers set amount of volume regardless of pressure • PIP is observed, and is determined by compliance and resistance • Although the PIP is observed the ventilator makes no attempt to adjust settings based on it • Downside is that you can end up with very high airway (and plateau) pressures if not careful!

42. Pressure Control (PC) • Patient receives flow from the ventilator at fixed pressure • Volume is determined by time (I-time), compliance, and resistance (the latter two may vary during the cycle) • Ventilator adjusts to accommodate PIP • Flow decreases throughout the breath (increased airway pressure as lungs fill, also compliance changes when lungs are more fully expanded) • The Bad: TV may vary breath to breath • The good: the vent will compensate for air leaks (such as a down balloon or for peds with uncuffed tubes that have a small leak around the subglottic tissue

43. PS / CPAP • Pressure Support and CPAP are ONLY to be used in spontaneously breathing patients • This allows patients to breathe with less effort • Recruits other alveoli • Pre-extubation PS helps allow the patient to breath on his own and “overcome tube resistance”. • PATIENT sets the I-time, TV

44. BiPAP • Is basically a modified CPAP • MUST BE SPONTANEOUSLY BREATHING • There is i-PEEP and e-PEEP • I = inspiratory • E = expiratory • I>E • Allows the patient to have an easier time with breathing, but will not initiate breaths • I-Time and TV determined by patient

45. PRVC • Pressure Regulated Volume Control • You set minute ventilation • You set PIP • Ventilator will adjust PIP to maintain parameters and it will deliver the set TV • Machine automatically compensates for changes in lung compliance to deliver TV! (how cool is that?) • Downside: doesn’t work well on a spontaneously breathing patient (airway pressures will change dramatically if the patient tries to breathe during the machine cycle!); also works very poorly with air leaks

46. SIMV • In essence it uses components of PC and VC and allows for spontaneous breathing, it is more of a “submode” than a mode of its own. • You set a mandatory rate (think of it as a “minimum” rate) • You set either Pressure Control, Volume Control or BOTH (which then you can refer to as VC-SIMV, PC-SIMV, or PRVC-SIMV) • You set Pressure Support (PEEP) • The machine cycles at a set rate but if a patient tries to take their own breath during the cycle the machine will deliver the set full ventilator breath. • The good: works like any of the other modes but allows for spontaneous breaths (decreases ventilator dependence during weaning) • The Bad: Patients with very high respiratory rates may generate huge minute ventilations and dramatic respiratory alkalosis

47. Vent Settings (Reccomendation Only!) • Our respiratory dept recommends: • Settings: • Mode: PC • PIP: 14-20 • TV: 6-8 ml/kg • Rate: 10-30

48. Vent Settings continued • Also available • SIMV is an acceptable alternative if you like • Volume control is somewhat shunned since it can cause many issues with high PIP and plateau pressures • PIP 14-20 for normal lungs (may have to be higher if low compliance, 18-25 is not uncommon) • Rate varies by age, consider: • 20-24 for infants/young children • 16-20 for older children • 12-16 for teenagers • I-time 0.5 – 1 second (higher rate = lower I-time) • PEEP 4-6 / PS 5-10 / TV 6-10mL/kg • All settings then adjusted based on the ABG!

49. Chasing the Dragon (or… at least ABG results) • pCO2 high: • Increase rate or TV or Both • Unless its critically high its probably best to adjust one or the other • If PIP is high, increase RATE (not TV)

50. Chasing (2) • pCO2 too low • Lower rate or TV or both • Again, recommend against doing both unless critical • PIP < 20 = reduce RATE • Decrease pressure control if TV is high (>15 ml/kg)