Pediatric Respiratory Pediatric Respiratory EmergenciesEmergencies

Moritz Haager

Dr. David Johnson

May 09, 2002

CaseCase

8 mo male w/ 2/7 Hx of URTI Sx and progressively labored breathing

Presents w/ tachypnea, indrawing, lethargy, ill looking child

380 / 200 / 60 / 88-90% on RA Dec’d AE and diffuse wheeze bilat., creamy d/c from

eyes ABG: 7.38 / 38 / 51 / 22/ -2 WBC 14.6 CXR: peri-bronchial cuffing in RLL

What’s your DDx for wheeze?What’s your DDx for wheeze?

BronchiolitisPneumoniaAsthmaForeign body aspirationCHFCFPertussisAnatomic abnormalities

What’s your approach to What’s your approach to bronchiolitis?bronchiolitis?

ABC’sOxygen?Bronchodilators (which one?)?Steroids?AntibioticsSupportive care Monitor for complications

BronchiolitisBronchiolitis Common contagious LRTI of infants + young children

(0-24 mo) Usually viral and self-limited illness

– RSV (60-90%)– Para-influenza, adenovirus, rhinovirus, influenza

Affects terminal bronchioles necrosis of ciliated cells inflammation w/ cellular debris + mucous plugging wheezing and inc’d WOB

Seasonal epidemics (winter months) Usually no long-term sequelae but may pre-dispose to

(or uncover) asthma

Are bronchodilators useful?Are bronchodilators useful? Controversial point in literature Meta-analysis looking at 15 RCT’s (mostly

salbutamol) concluded moderate short-term benefit from bronchodilator therapy, but no effect on admission rate or oximetry

– Kellner et al. 1996. Arch Ped Adol Med. 150: 1166-72

Cochrane systematic review of 394 kids in 8 trials showed 54% improved clinically vs.. 25% of placebo

Concluded modest short-term symptomatic benefit; need more studies to better elucidate utility

– Kellner et al. 2002. Coch Data Sys Rev. (1)

Salbutamol or Epinephrine?Salbutamol or Epinephrine? 4 RCT’s show epinephrine (racemic or L-epi) as

appearing to be superior to salbutamol All found significant symptomatic improvement,

and two found dec’d admission rate or shortened hospital stay; no adverse effects noted

Only 2 were in ED setting– Reijonen et al. 1995. Arch. Ped. Adol. Med. 149: 686-92– Menon et al. 1995. J. Ped. 126: 1004-007– Sanchez et al. 1993. J. Ped. 122: 145-51– Bertrand et al. 2001. Ped. Pulmonolgy. 31: 284-8

Hartling and Klassen in process of preparing a Cochrane review

Epi appears superior based on current evidence

What about Atrovent?What about Atrovent?

Double-blind placebo-controlled RCT of 69 infants 6wks – 24 mo w/ acute bronchiolitis

Randomized to either salbutamol + ipratropium or salbutamol + placebo

No sig difference in admission rate, RR, WOB, wheezing, or O2 sats

No additional benefit when given in addition to salbutamol.

– Schuh et al. 1992. Pediatrics. 90: 920-23

Is there a role for Steroids?Is there a role for Steroids?

3 RCT’s all fail to show benefit – Roosevelt et al. 1990. Lancet. 348: 292-95– Van Woensel et al. 1997. Thorax. 52: 634-47– Klassen et al. 1997. J. Ped. 130: 191-196.

3 more recent studies support this and also fail to show any long-term benefit in reducing risk of post-bronchiolitis wheezing or asthma

– Van Woensel et al. 2000. Ped. Pulmonology. 30: 92-6– Wong et al. 2000. Euro. Resp. J. 15: 388-94– Cade et al. 2000. Arch. Dis. Child. 82: 126-30

Literature does not support use in bronchiolitis Patel et al are preparing a Cochrane review

Does this Kid need Antibiotics?Does this Kid need Antibiotics? Not routinely indicated, but

– One study shows ~86% of kids w/ bronchiolitis have concomitant OM

– 5-10% have M. pneumoniae or Chlamydia co-infection Consider Tx in kids with:

– OM and high fever– Atypical features– More ill than expected – CXR evidence of pneumonia (other than atelectasis)

This child received IV amoxicillin for ill appearance

Your student suggests RibavirinYour student suggests Ribavirin Synthetic nucleotide anologue w/ virostatic properties Expensive, possibly teratogenic, can cause

bronchospasm Controversial, but mounting evidence it does not work:

– At least 3 RCT’s fail to show benefit– Everard et al. 2001. Resp. Med. 95: 275-80– Guerguerin et al. 1999. Am. J. Resp. Crit. Care Med. 160: 829-34– Moler et al. 1996. J. Ped. 128: 422-28

– Cochrane review of 378 infants < 6mo in 10 trials suggests possible decrease in length of stay, but studies lack sufficient power.

– Randolph and Wang. 2002. Coch Data Sys Rev. Issue 1

Bottom line: not indicated in ED

Other Treatments for BronchiolitisOther Treatments for Bronchiolitis Shuang huang lian

– 1 RCT shows dec’d duration of Sx Heliox

– One RCT in PICU showing benefit Surfactant

– Case reports in PICU setting ECMO

– Case reports of benefit in premies or unstable pts refractory to conventional Tx

Prevention– RSVIG– Palivizumab

What complication can arise?What complication can arise?

Hypoxemia / respiratory failure Apnea (esp. in <6 mo) Hypercarbia Pneumonia (viral or bacterial) Concomitant OM Long-term: ? Asthma – some studies suggest inc’d

risk esp. in kids w/ inc’d IgEMortality < 1%, and usually occurs in children w/

underlying heart dz, lung dz, or prematurity.

Are there any predictors of M+M?Are there any predictors of M+M?

Predictors of severe disease:– GA < 34 wks– SpO2 < 95%– RR >70– Age < 3 mo– Ill or toxic appearance– Atelectasis on CXR

Presence or absence of all 6 has PPV of 81% and NPV of 88% for severe course

– Shaw et al. 1991. Am. J. Dis. Child. 145: 151-55

Who needs intubation?Who needs intubation?

2-7 % of hospitalized infants end up requiring intubation for resp. failure

Indications for intubation:– Severe resp. distress– Apnea– Hypoxia or hypercapnea– Lethargy– Poor perfusion– Metabolic acidosis

– Wright et al. 2002. Emerg Med Clin NA. 20: 93-113

CaseCase

3 yo female presents w/ 3/7 Hx of coryza, fever, and a “harsh” cough

Today started making noise with every breath and hoarse voice which is worse at night

O/E: 386 / 120 / 35 / 96% RAInspiratory stridor

What’s your DDx for stridor?What’s your DDx for stridor?

EpiglottitisBacterial tracheitisRetro-pharyngeal abscessCroupUvulitisForeign body obstructionHemangiomaNeoplasm

What’s your approach to What’s your approach to Croup?Croup?

ABC’sOxygen?Humidification?Epinephrine?Steroids?Intubation

CroupCroup

= Laryngotracheobronchitis, viral croup Common URTI and cause of stridor in infants and

children 6 mo – 6 yo Viral infection inflammation of subglottic area

stridor (can be biphasic in severe cases) potentially hypoxia and death (rare)

Biphasic: peaks in fall and winter Etiology:

– Parainfluenza 1 + 3 (>65%) > RSV > Parainfluenza 2 > Influenza A > M. pneumoniae > Influenza B

Humidification: does it work?Humidification: does it work? Long-standing first-line Tx at home Anecdotal evidence studies to date fail to show objective benefit from

mist therapy, one of which was an RCT of 16 pts receiving either RA or humidified air

– Bourchier et al. 1984. Aust. Pediatr. J. 20:289-91

Reports of Pseudomonas contamination and hyper-sensitivity reactions

We need a larger RCT to clear this up Cochrane review by Moore and Little in progress

EpinephrineEpinephrine

- effects: dec’d bronchial secretions + edema- effects: bronchodilation, tachycardiaMost studies on racemic epinephrine but at

least one double-blind RCT suggests equivalence to L-epi

– Waisman et al. 1992d. Pediatrics. 89: 302-06

0.5 ml 2.25% racemic epinephrine = 5 ml 1:1000 L-epinephrine

L-epi more available and less expensive

Does Epi work in Croup?Does Epi work in Croup? 5 prospective double-blind RCT’s of epinephrine in

croup 4 demonstrate decreased airway obstruction with

effect lasting 2 hours– Kuusela et al. 1988. Acta Paed. Scand. 77: 99-104– Taussig et al. 1978. Am J Dis Child 132: 484-87– Westley et al. 1978. Am J Dis Child 132: 484– Fogel et al. 1982. J. Ped. 101: 1028-31

One failed to show any benefit but unsure of length of observation time

– Gardner et al. 1973. Pediatrics 52: 52-55

Epinephrine appears to offer symptomatic benefit

Does Epi help decrease Does Epi help decrease admission?admission?

3 studies totaling 166 pts who got epi + steroids, observed for 2-3 hrs and then discharged w/ arranged f/u in 48 hrs

47/50 required no further Tx in one study, while the other 2 were able to D/C 55% and 51% of pts w/ only 1 recurrence of resp. distress in pts who otherwise would have been admitted

– Kelly et al. 1992. Am J Emerg 10: 181-83– Ledwith et al. 1995. Ann Emerg Med 25: 331-37– Prendergast et al. 1994. Am J Emerg Med. 12: 613-16

How much epi can we safely give?How much epi can we safely give? Studies give 0.05 ml/kg or 0.25-0.5 ml a of 2.25% RE

sol’n; don’t often quote frequency Locally known to give 0.5 ml q2h O/N Case report of MI in pediatric pt following multiple

doses of RE via neb – Developed short run of VT, and mild transient CP– Abnormal ECG and elevated CK-MB– Structurally normal heart as per echo + angio but small

infarct seen by nuclear stress scan– Butte et al. 1999. Pediatrics 104: e9

Suggests we should be more cautious

SteroidsSteroids

Postulated to work by anti-inflammatory effect to decrease edema, but exact mechanism uncertain

Onset of effect usually quoted as being ~6 hrs, but some have observed effect as early as 2 hrs

Are Steroids useful in Croup?Are Steroids useful in Croup? One meta-analysis comprising 1286 pts in 10 RCT’s and 2 RCT’s

quoted as strong evidence demonstrating faster clinical improvement, dec’d likelihood of intubation, and shorter admissions. Also suggests better effect w/ higher doses.

– Kairys et al. 1989. Pediatrics. 83: 683-93– Super et al. 1989. J Ped. 115: 323-29– Kuusela and Vesikari. 1988. Acta Paed Scand. 77: 99-104

More recent meta-analysis of 24 RCT’s ( incl. 15 new studies) demonstrates symptomatic improvement, fewer interventions, and shorter hospital stays in steroid-treated children w/ NNT of 5-7, but did not show dec’d risk of intubation

– Ausejo et al. 1999. BMJ. 319: 595-600

Cochrane review concluded CS are effective in relieving the Sx of croup and decreasing need for co-interventions, and length of stay in hospital

– Ausejo et al. 2002. Coch Data Sys Rev Issue1

What steroid, what route, what What steroid, what route, what dose?dose?

IM Dexamethasone was shown to be superior to budesonide in one RCT

– Johnson et al. 1998. N Engl J med. 339: 498-503

Dexamethasone can be given IM or PO; no head-to-head comparison studies

Dose more controversial:– Kairys et al: inc’d benefit w/ doses > 0.3 mg/kg– Another double-blind RCT of 120 children concluded a dose of 0.15

mg/kg just as effective– Geelhoed and Macdonald. 1995. Ped Pulmonolgy. 20: 362-68

– No studies have shown any safety concerns or adverse effects with dexamethasone even at doses up to 0.6 mg/kg

Current recommendation is Dex 0.6 mg/kg PO– Ausejo et al. 1999. BMJ. 319: 595-600

Does giving steroids early in the Does giving steroids early in the ED affect disposition or ED affect disposition or

Outcome?Outcome? At least 4 RCT’s, all suggesting improved clinical

status with early steroids 1 study only had 80% power to detect 67% difference

in admission rate– Johnson et al. 1996. Arch Ped Adol Med 150: 349-55

2 suggest decreased admission rate– Johnson et al. 1998. N Engl J Med. 339: 498-503– Klassen et al. 1994. N Engl J Med. 331: 285-89

1 study suggest no sig benefit from nebulized budesonide in addition to PO dex

– Klassen et al. 1998. JAMA 279: 1629-32

Steroids early appear to be helpful

Who do you admit? Who do you admit?

Most pts can be dischargedAdmission for:

Marked distress / ill looking Hypoxia Dehydration Poor Tx response / persistent stridor + other Sx Other medical co-morbidities (prem, cardiac, pulm) Young age Social: far from hospital, questionable f/u, scary

story, anxious parents

Who do you intubate?Who do you intubate?

Very rare since advent of steroidsUse ½ size smaller than calculatedNo clear guidelines; exercise clinical

judgment

CaseCase

13 yo boy w/ known asthma presents w/ runny nose, cough, and inc’d SOB

O/E: 373 / 100 / 22 / 96% RAMild exp wheezesPEF 300 compared to usual of 375

What’s your DDx for What’s your DDx for wheezing?wheezing?

Asthma Foreign body Bronchiolitis CHF Anatomic (vascular ring, laryngomalacia..) CF Pertussis Pneumonia

AsthmaAsthma

Most common chronic dz of childrenRising M + M: mortality doubled 1977-85Chronic inflammatory dz characterized by

exacerbations + remissions, w/ airway obstruction partially reversible w/ meds

Specific triggersGoal of ED care is to coordinate w/ existing

care plan as much as possible

What’s your approach?What’s your approach?

Initial assessment ABC’s

Initial management Oxygen, bronchodilators, steroids,

Identify risk factors and assess Tx responseDisposition and F/U

Mortality Risk FactorsMortality Risk Factors

Prior sudden exacerbations

Prior intubations / ICU stays

>2 admissions in past year >3 ED visits in past yr Admission or ED visit in

past month >2 ventolin inhalers per

month

Currently on, or recent weaning from, steroids

Poor perception of airflow obstruction

Co-morbid disease Low SE status, urban

residence Psychiatric dz Sensitivity to Alternaria

Clinical Scoring SystemsClinical Scoring Systems

Most common is pulmonary index– Based on physical exam findings including RR,

wheezing, I-E ratio, and use of accessory muscles

None have sufficient validation to be used in disposition decisions

Pulmonary Function TestsPulmonary Function Tests

Formal PFT’s are best to measure degree of obstruction but not convenient in ED

PEF commonly used – correlates w/ FEV1

– Effort-dependant, pt needs to stand– Compare w/ personal best or standard tables

PEF pred Severity<30% possibly life-threatening<50% severe50-80% moderate>80% mild

Pulse Oximetry + OxygenPulse Oximetry + Oxygen No official agreement on normal values:

– NAEPEP states anyone <90% should get O2

– Common practice in the region is <92%– Acute asthma pts w/ SaO2 <95% were more likely to be

admitted and more likely to return to ED if discharged– Geelhoed et al. 1990. J Ped. 117: 907-09

– SaO2 <93% found to be 35% sensitive and 93% specific fro admission

– Mayefsky and el_Shianway. 1992. Ped Emerg Care 8: 262-4

Limitations of pulse oximetry:– Dec’d O2-carrying capacity– Low perfusion state– Provides no information on ventilation

-agonists -agonists

Salbutamol is 1st line therapy in asthma Epinephrine has no benefit over salbutamol

– Klassen et al. 2000. Acad Emerg Med 7: 1097-103

Mechanism of action:– Relax bronchial smooth muscle– Increase secretion of water from mucous glands– Increase mucociliary clearance

Controversies:– Route of administration in ED– New pure R isomers (levalbuterol)– Continuous therapy

MDI or Nebulizer?MDI or Nebulizer? Nebulizers enormously popular in ED Cost of nebulizer is ~50% greater Most people use MDI’s at home 5 studies show either equivalence, or even superiority of MDI

over nebulizer One double-blind RCT in 5-17 yo subjects showed no difference

– Schuh et al. 1999. J Ped. 135: 22-27

Similar study in pts aged 1-4 yo showed dec’d admission rate + less wheezing in MDI group

– Leversha et al. 2000. J Ped 136: 497-502– Ploin et al. 2000. Pediatrics. 106: 311-17

MDI makes more sense in ED

IV SalbutamolIV Salbutamol Few well designed trials Cardiotoxicity: need to monitor cardiac funxn + K+

Rationale: may get to non-ventilated lung areas One double-blind RCT of IV salbutamol in addition

to continuous nebulized salbutamol showed more rapid improvement than control group

Did not follow cardiac enzymes– Browne et al. 1997. Lancet. 349: 301-305

Current recommendation is to consider early on in severe Tx-refractory cases

Continuous Continuous -agonist therapy-agonist therapy

Usually administered as 0.5 mg/kg/h , to a maximum of 15 mg

Requires cardiopulmonary monitoringsome studies (mostly adult) showing

improved asthma scores, but no difference in PEF’s, admission rates, or adverse effects

– Besbes-Ouanes et al. 2000. Ann Emerg Med 36:198-203

Jury still out – may consider if tx-refractory

LevalbuterolLevalbuterol Salbutamol (albuterol) = R + S isomers

– R isomer bronchodilation– S isomer bronchoconstriction– Manifests clinically as tolerance after repeated use

Levalbuterol is pure R isomer– ~5x cost of salbutamol– One double-blind crossover study of 33 kids suggests

better than or equivalent to salbutamol w/ less side effects, but in stable pts (not ED setting)

– Gawchik et al. 1999. J Allergy Clin Immunol 103: 615-21

– No head-to-head trials in ED setting Not indicated for use at this time; needs further study

Anti-CholinergicsAnti-Cholinergics Ipratropium bromide

– Similar to atropine; bromide group prevents systemic effect– Inhibits Ach-mediated bronchoconstriction– Only useful in addition to -agonist– Takes 60-90 min to reach peak effect– Given as 250 g x3 doses or 500 g x2 doses by nebulizer over

1 hour; repeat q2-4h prn One meta-analysis and a Cochrane review show:

– Multiple doses (but not single doses) decrease admissions in mod - severe exacerbations w/ NNT of 12

– No conclusive evidence for use in mild-moderate cases– Plotnick and Ducharme. 1998. BMJ. 317: 971-977– Plotnick and Ducharme. 2002. Coch Data Sys Rev. Issue 1

NAEPP: use in severely ill kids, and those not responding to high dose -agonist therapy

SteroidsSteroids Meta-analysis of 30 RCT’s + recent Cochrane

review show:– Early steroids dec’d admission rates (NNT = 8)– IV = PO in efficacy; no significant adverse effects

– Rowe et al. 1992. Am J Emerg Med. 10: 301-310– Rowe et al 2002. Coch Data Sys Rev. Issue 1

– Speed resolution of obstruction– Potentiate effects of -agonists

Steroids prevent relapse w/ NNT 13, and decrease need for -2 agonists

– Rowe et al 2002. Coch Data Sys Rev. Issue 1

Indicated for most pts in ED

Early inhaled steroids?Early inhaled steroids? Controversial One double-blind RCT comparing PO prednisone and

inhaled budesonide in 185 acute asthma pts d/c’d from ED suggests equivalence in preventing relapse

– FitzGerald et al. 2000. Can Resp J. 7: 61-7

Double-blind RCT of 22 kids treated w/ either budesonide or PO prednisolone showed similar benefit

– Volovitz et al. 1998. J Allergy Clin Immunol. 102: 605-9

Another double-blind RCT of 188 pts (no kids) found additional benefit of inhaled budesonide in addition to PO prednisone in preventing relapse in pts discharged from ED

– Rowe et al. 1999. JAMA. 281: 2119-26

Early inhaled steroids?Early inhaled steroids? 2 separate Cochrane reviews looking at ICS

– One looked at role of ICS in ED 7 trials (2 pediatric) involving 352 pts ICS alone can decrease admission rates ICS +other CS non-sig trend towards dec’d admission Inconclusive evidence for benefit of adding ICS

– Edmonds et al. 2002. Coch Data Sys Rev. Issue 1

– 2nd review looked at role of ICS after discharge 3 trials of 909 pts found non-sig trend towards dec’d relapse in ICS

and other CS ICS vs. other CS alone: no sig differences (severe cases excluded) Concluded no evidence to support addition or substitution of ICS

for systemic CS, but may have yet undefined role in mild exacerbations

– Edmonds et al. 2002. Coch Data Sys Rev. Issue 1

MagnesiumMagnesium

Being re-discovered?MOA: counters Ca++ ions preventing

smooth muscle contractionCan cause N + V, weakness, facial flushing.Low cost, easy administration, availabilityGood evidence for efficacy in kidsDose: 25 – 40 mg/kg IV; higher doses

appear to produce greater improvement

Magnesium: is it useful?Magnesium: is it useful? two RCT’s showed improved PFT’s, dec’d

admission, and no adverse effects with Mg– Ciarallo et al. 1996. J Ped 129: 809-814– Ciarallo et al. 2000. Arch Ped Adol Med. 154: 979-83

2 meta-analyses both agreed current evidence supports use of Mg in adults w/ severe asthma exacerbations

– Rowe et al. 2000. Ann Emerg Med. 36: 181-190.– Alter et al. 2000. Ann Emerg Med. 36: 191-97

Consider in moderately – severely ill pts failing to respond to salbutamol

Who would use Aminophylline?Who would use Aminophylline? Good evidence that it has no benefit over salbutamol Significant toxicity Some suggestion it may be useful in the most severe

pts in an ICU setting Cochrane review:

– Found significant improvement in FEV1 but no effect on length of stay or need for co-interventions

– Inc’d risk of vomiting (RR 3.69)– Concluded should be considered in admitted Tx-refractory

cases of severe asthma– Mitra et al. 2002. Coch Data Sys Rev. Issue 1

Not indicated in ED

Other TxOther Tx

Heliox– Helium + O2: dec’d density improves air flow– Often get hypoxia b/c need at least 60% helium – Cochrane review of 4 RCT's (1 peds) in ED concluded

no evidence for use in ED– Rodrigo et al. 2002. Coch Data Sys Rev. Issue 1

Leukotriene Antagonists– One abstract describes improved outcome in ED

setting, but no RCT’s– Silvermanm et al. 1999. Ann Emer Med. 34(suppl):1

Who gets intubated?Who gets intubated?

Last resort RSI protocol using ketamine Careful to prevent inc’d intrathoracic pressure

dec’d venous return arrest Indications (Rosen):

– Apnea– PaCO2 > 42 mm Hg and worsening, or no response to

Tx– Signs of impending resp failure

Any predictors of admission?Any predictors of admission?

Model for predicting admission:– Age 6 yo or younger– Male gender– Requiring O2

– Interval severity of asthma– Severity of wheeze at initial presentation– Post-Tx SpO2 (most imp)

Predictive accuracy of 90%, with 86% sensitivity and 88% specificity

– Chey et al. 1999. J Clin Epi 52(2): 1157-63

CaseCase

2 yo male w/ fever, cough, vomiting x 2/7Looks moderately ill but not lethargicO/E: 389 / 198 / 60 / 87% RAMild inc’d WOB, dec’d AE on RULNormal WBC

PneumoniaPneumoniaUsually in 1st year of lifeViral causes account for 60-90% (RSV, paraflu)75% of deaths due to bacterial causesBacteriology is age-dependent

– GBS, E. coli, Listeria, Ureaplasma in neonate– Chlamydia at 3-19 wks– Strep pneumoniae most common all other age groups– Mycoplasma pneumoniae usually >5yo– Bordetella pertussis usually < 6mo

PneumoniaPneumonia

Treatment decisions based on– Age– Likely pathogen– Degree of illness

< 3mo amp =+ gent or amp + 3d gen ceph > 3mo

– Inpatients: IV cefuroxime or cefotaxime +/- erythro– Outpatients: macrolide (azithro) or clavulin or TMP-SMX;

must be reassessed in 24 hrs– If Mycoplasma use macrolide or TMP-SMX

Who needs admission?Who needs admission?

No CAP score in kids Toxic appearance Vomiting or dehydration Respiratory distress Pleural effusion (needs investigation) Immunocompromised Psycho-social factors Age < 6 mo