RESPIRATORY FAILURE - PDF document

RESPIRATORY FAILURE Definition Inability to meet one's need for tissue o

xygenation and elimination of CO2, often but not always associated with

distress.Will focus on Pulmonary aspects of this process.50% of pediatr

ic ICU admissions.Produced by a wide variety of diseases. RESPIRATORY FA

ILURE Orientation # Amelioration ofpathophysiologyproducing ARF, RESPIR

ATORY FAILURE Developmental Physiology # Cartilage spread to segmental

bronchus, 12 wgest.# Neonates,Premies: Pause, Apnea, Flat CO2 response

, RESPIRATORY FAILURE Distribution of Ventilation # More ventilati

on to bases in healthy lungs due to less P-transpulm. at end expiration.

# Shift in pressure -volume relationship can change this dramatically. R

ESPIRATORY FAILURE FRC # Fasterdesaturationat lower FRC.# Lower FRC fav

orsatalectasis. RESPIRATORY FAILURE Convergence of FRC and CC Surgery,At

alectasisARDS,Pneumonitis RESPIRATORY FAILURE Decreased Total Compliance

Decreased CLIncreased Recoil ARDS,pneumonitisedema,neartdrowning Asthma

, BronchiolitisExcess PEEP or CPAPVolume loss Atalectasis Supine

positionDecreased CWThoracic Trauma or SurgeryAbdominal SurgeryDiaphragm

atic LoadingAbdominal DistensionPD, MASTPneumothoraxPleural Effusio

nThoracic Bony deformities RESPIRATORY FAILURE Sites of Increased Airway

Resistance # In Adults --Upper Airway, Nose.# In Children --Periphe

ral Airways.: IncreasedIntrapleuralintrathoracicairways.# Worse with B

PD, alpha-1-antitrypsindeficiency due to poorcartilege.#Extrathoracicair

way effected on inhalation. RESPIRATORY FAILURE Surfactant #LaPlace'sLaw

P = 2 T / r# Made by type IIpneumocytes. RESPIRATORY FAILURE West

Zones I (pulmonaryaretery) RESPIRATORY FAILURE HPV # Alveolar Hypoxia

leads to local pulmonaryvasoconsstriction.# Usually useful to match per

fusion to ventilation.# With whole lung hypoxemia it produces pulmonary

hypertension, and possible R to L shunt via PFO.pulmonary hypertension

RESPIRATORY FAILURE Lung Units Idealized alveoliMatched V / QDead RESPI

RATORY FAILURE Virtual Shunt Lines 2030405060708090100 05%10% RESPIRATOR

Y FAILURE Exclusions # Physiology review has focused on lung physiology

.# Also important, but not included in this review are:2. Neuromuscular

transmission.3. Muscular function.4. Toxicology5. Cardiac Function and

O2 delivery. RESPIRATORY FAILURE Sorting it Out 2 Extrathoraciclarge air

wayIntrathoraciclarge airway RESPIRATORY FAILURE Hypoxia # The four bas

ic mechanisms which can produce hypoxia.1. Inadequate FiO2.2. Decrease

d Ventilation.3. Shunt (pulmonary or cardiac).4. Decreased Cardiac Ou

tput. RESPIRATORY FAILURE Oxygen # Simple masks, NasalCannula, imposs

ible to know FiO2. Better withVenturimask.# Non-Rebreathermask or Hoo

d for infant provide known RESPIRATORY FAILURE Severity 2 �9. S

hunt Fraction 15 -20%. RESPIRATORY FAILURE Intubation #Preoxygenategene

rously. Fill FRC with O2 may take a #Cricoidpressure.#Laryngoscopyand

Intubation, Gently RESPIRATORY FAILURE InEpiglottitisyou need to secure

RESPIRATORY FAILURE Supraglottitis Acute infection of the Epiglottis a

ndAryepiglotticSudden onset of sore throat,dysphagia, often withstridora

nd shortness of breath.Usually with high fever andbacteremia. RESPIRATOR

Y FAILURE Epiglottitisvs. Croup Epiglottitisvs. CroupStridorYes, less wi

th more obstruct. Yes RESPIRATORY FAILURE Stridormay or may not be pr

esent RESPIRATORY FAILURE ExtrathoracicAirway ExtrathoracicAirway Supras

ternal,SupraclavicularRetractionsStridormay be less with worse obstructi

on RESPIRATORY FAILURE UAO: An Algorithm Airway Obstruction Respiratoryf

ailure ormoribund AccessMusc. Stridorwith IIIIII RESPIRATORY FAILURE Alg

orithm II management i.e.Intubation RESPIRATORY FAILURE X-Ray Features

Enlarged epiglottis, lack of centrallucencyBalooningofhypopharynxary-ep