Diagnosis and Diagnosis and Management of Acute Management of Acute

Respiratory FailureRespiratory Failure

Diagnosis and Diagnosis and Management of Acute Management of Acute

Respiratory FailureRespiratory Failure

ARF 1 ARF 1 ®

ObjectivesObjectivesObjectivesObjectives

• Define and classify acute respiratory failureDefine and classify acute respiratory failure

• Describe pathophysiology of acute Describe pathophysiology of acute respiratory failurerespiratory failure

• Discuss clinical manifestations Discuss clinical manifestations

• Review oxygen supplementation strategiesReview oxygen supplementation strategies

• Discuss noninvasive positive-pressure Discuss noninvasive positive-pressure ventilationventilation

• Define and classify acute respiratory failureDefine and classify acute respiratory failure

• Describe pathophysiology of acute Describe pathophysiology of acute respiratory failurerespiratory failure

• Discuss clinical manifestations Discuss clinical manifestations

• Review oxygen supplementation strategiesReview oxygen supplementation strategies

• Discuss noninvasive positive-pressure Discuss noninvasive positive-pressure ventilationventilation

ARF 2

ARF 2 ®

Acute Respiratory FailureAcute Respiratory FailureAcute Respiratory FailureAcute Respiratory Failure

• HypoxemicHypoxemic

–Room air PaORoom air PaO22 50 torr (6.7 kPa) 50 torr (6.7 kPa)

• HypercapnicHypercapnic

–PaCOPaCO22 50 torr (6.7 kPa) 50 torr (6.7 kPa)

• Acute vs chronic Acute vs chronic

• HypoxemicHypoxemic

–Room air PaORoom air PaO22 50 torr (6.7 kPa) 50 torr (6.7 kPa)

• HypercapnicHypercapnic

–PaCOPaCO22 50 torr (6.7 kPa) 50 torr (6.7 kPa)

• Acute vs chronic Acute vs chronic

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Pathophysiology of Pathophysiology of HypoxemiaHypoxemia

Pathophysiology of Pathophysiology of HypoxemiaHypoxemia

• Ventilation/perfusion mismatchVentilation/perfusion mismatch• Shunt effectShunt effect

• Decreased diffusion of ODecreased diffusion of O22 • Alveolar hypoventilationAlveolar hypoventilation• High altitudeHigh altitude

• Ventilation/perfusion mismatchVentilation/perfusion mismatch• Shunt effectShunt effect

• Decreased diffusion of ODecreased diffusion of O22 • Alveolar hypoventilationAlveolar hypoventilation• High altitudeHigh altitude

Pathophysiology of Pathophysiology of HypercapniaHypercapnia

• Decreased tidal volume and/or Decreased tidal volume and/or respiratory rate respiratory rate

• Inability to sense elevated PaCOInability to sense elevated PaCO2 2

• Inability to signal effector Inability to signal effector mechanisms mechanisms

• Inability to effect a response from Inability to effect a response from respiratory musclesrespiratory muscles

• Decreased tidal volume and/or Decreased tidal volume and/or respiratory rate respiratory rate

• Inability to sense elevated PaCOInability to sense elevated PaCO2 2

• Inability to signal effector Inability to signal effector mechanisms mechanisms

• Inability to effect a response from Inability to effect a response from respiratory musclesrespiratory muscles

Increased Dead SpaceIncreased Dead SpaceIncreased Dead SpaceIncreased Dead Space

• HypovolemiaHypovolemia

• Low cardiac outputLow cardiac output

• Pulmonary embolusPulmonary embolus

• High airway pressuresHigh airway pressures

• Short-term compensation by increasing Short-term compensation by increasing tidal volume and/or respiratory ratetidal volume and/or respiratory rate

• HypovolemiaHypovolemia

• Low cardiac outputLow cardiac output

• Pulmonary embolusPulmonary embolus

• High airway pressuresHigh airway pressures

• Short-term compensation by increasing Short-term compensation by increasing tidal volume and/or respiratory ratetidal volume and/or respiratory rate

Manifestations of Manifestations of Respiratory DistressRespiratory DistressManifestations of Manifestations of Respiratory DistressRespiratory Distress

• Altered mental statusAltered mental status

• Increased work of breathingIncreased work of breathing

– TachypneaTachypnea

– Accessory muscle use, retractions, Accessory muscle use, retractions, paradoxical breathing pattern paradoxical breathing pattern

• Catecholamine releaseCatecholamine release

– Tachycardia, diaphoresis, hypertensionTachycardia, diaphoresis, hypertension

• Abnormal arterial blood gas valuesAbnormal arterial blood gas values

• Altered mental statusAltered mental status

• Increased work of breathingIncreased work of breathing

– TachypneaTachypnea

– Accessory muscle use, retractions, Accessory muscle use, retractions, paradoxical breathing pattern paradoxical breathing pattern

• Catecholamine releaseCatecholamine release

– Tachycardia, diaphoresis, hypertensionTachycardia, diaphoresis, hypertension

• Abnormal arterial blood gas valuesAbnormal arterial blood gas values

ARF 7ARF 7®

Acute Respiratory Failure Acute Respiratory Failure ManagementManagement

Acute Respiratory Failure Acute Respiratory Failure ManagementManagement

• Oxygen supplementationOxygen supplementation

– Increase FIncrease FIOIO22

–Match flow between delivery Match flow between delivery device and inspiratory demanddevice and inspiratory demand

–High- vs. low-oxygen systemsHigh- vs. low-oxygen systems

–High- vs. low-flow systemsHigh- vs. low-flow systems

• Oxygen supplementationOxygen supplementation

– Increase FIncrease FIOIO22

–Match flow between delivery Match flow between delivery device and inspiratory demanddevice and inspiratory demand

–High- vs. low-oxygen systemsHigh- vs. low-oxygen systems

–High- vs. low-flow systemsHigh- vs. low-flow systems

ARF 8ARF 8®

Nasal CannulaNasal Cannula

• 100% oxygen 100% oxygen delivereddelivered

• Low flow Low flow

–<0.5–5.0 L/min<0.5–5.0 L/min

• Low oxygen Low oxygen

–FFIOIO22 <0.4–0.5 <0.4–0.5

Air-Entrainment Face MaskAir-Entrainment Face MaskAir-Entrainment Face MaskAir-Entrainment Face Mask

• 100% O100% O22 + entrainment + entrainment

devicedevice

• High flowHigh flow

• Variable oxygenVariable oxygen

–FFIOIO22 0.24–0.5 0.24–0.5

• 100% O100% O22 + entrainment + entrainment

devicedevice

• High flowHigh flow

• Variable oxygenVariable oxygen

–FFIOIO22 0.24–0.5 0.24–0.5

Aerosol Face MaskAerosol Face Mask

• 100% O100% O22 + large-bore tubing + large-bore tubing

• Nebulizer/ONebulizer/O22 blender blender

• Flow matchingFlow matching

– If mist disappears in If mist disappears in inspiration, air is entrainedinspiration, air is entrained

• Moderate-flow, variable FModerate-flow, variable FIOIO22

devicedevice

• 100% O100% O22 + large-bore tubing + large-bore tubing

• Nebulizer/ONebulizer/O22 blender blender

• Flow matchingFlow matching

– If mist disappears in If mist disappears in inspiration, air is entrainedinspiration, air is entrained

• Moderate-flow, variable FModerate-flow, variable FIOIO22

devicedevice

Reservoir Face MaskReservoir Face MaskReservoir Face MaskReservoir Face Mask

• Reservoir bag filled Reservoir bag filled with 100% Owith 100% O22

• High oxygen High oxygen

• High flow High flow

• Reservoir bag filled Reservoir bag filled with 100% Owith 100% O22

• High oxygen High oxygen

• High flow High flow

Resuscitation Bag-Mask-Resuscitation Bag-Mask-Valve DeviceValve Device

Resuscitation Bag-Mask-Resuscitation Bag-Mask-Valve DeviceValve Device

• 100% O100% O2 2

• High flow (> 15 L/min)High flow (> 15 L/min)

• Emergency equipmentEmergency equipment

• Little to no air entrainment Little to no air entrainment with firm fit with firm fit

• 100% O100% O2 2

• High flow (> 15 L/min)High flow (> 15 L/min)

• Emergency equipmentEmergency equipment

• Little to no air entrainment Little to no air entrainment with firm fit with firm fit

Noninvasive Positive-Noninvasive Positive-Pressure Ventilation (NPPV)Pressure Ventilation (NPPV)

Noninvasive Positive-Noninvasive Positive-Pressure Ventilation (NPPV)Pressure Ventilation (NPPV)• Ventilatory assistance with controlled FVentilatory assistance with controlled FIOIO22

• Unilevel or bilevel pressure supportUnilevel or bilevel pressure support

• Nasal or face maskNasal or face mask

• Volume or pressure-cycled ventilatorVolume or pressure-cycled ventilator

• Most effective with alert, oriented and Most effective with alert, oriented and cooperative patientcooperative patient

• Successful in hypoxemic and hypercapnic Successful in hypoxemic and hypercapnic failure failure

• Ventilatory assistance with controlled FVentilatory assistance with controlled FIOIO22

• Unilevel or bilevel pressure supportUnilevel or bilevel pressure support

• Nasal or face maskNasal or face mask

• Volume or pressure-cycled ventilatorVolume or pressure-cycled ventilator

• Most effective with alert, oriented and Most effective with alert, oriented and cooperative patientcooperative patient

• Successful in hypoxemic and hypercapnic Successful in hypoxemic and hypercapnic failure failure

ARF 14 ARF 14 ®

Relative Contraindications Relative Contraindications for NPPVfor NPPV

Relative Contraindications Relative Contraindications for NPPVfor NPPV

• Decreased level of consciousnessDecreased level of consciousness

• Poor airway protective reflexesPoor airway protective reflexes

• Copious secretionsCopious secretions

• Cardiovascular instabilityCardiovascular instability

• Progressive pulmonary decompensationProgressive pulmonary decompensation

• Upper gastrointestinal hemorrhageUpper gastrointestinal hemorrhage

• Decreased level of consciousnessDecreased level of consciousness

• Poor airway protective reflexesPoor airway protective reflexes

• Copious secretionsCopious secretions

• Cardiovascular instabilityCardiovascular instability

• Progressive pulmonary decompensationProgressive pulmonary decompensation

• Upper gastrointestinal hemorrhageUpper gastrointestinal hemorrhage

ARF 15 ARF 15 ®

Initiation of NPPVInitiation of NPPV

• Set FSet FIOIO2 2 at 1.00at 1.00

• Hypoxemic failureHypoxemic failure

– Inspiratory pressure (IPAP) 10 cm HInspiratory pressure (IPAP) 10 cm H22OO

– Expiratory pressure (EPAP) 5 cm HExpiratory pressure (EPAP) 5 cm H22OO

– Titrate EPAP in 2 cm HTitrate EPAP in 2 cm H22O incrementsO increments

• Ventilatory failureVentilatory failure

– IPAP 10 and EPAP 2 cm HIPAP 10 and EPAP 2 cm H22OO

– Titrate IPAP in 2 cm HTitrate IPAP in 2 cm H22O incrementsO increments

Initiation of NPPVInitiation of NPPV

• Make changes every 15-30 minutesMake changes every 15-30 minutes

• Monitor vital signs, appearance, Monitor vital signs, appearance, pulse oximetry and blood gasespulse oximetry and blood gases

• Head of bed at 45Head of bed at 45 angle angle

• Consider gastric decompressionConsider gastric decompression

• Intubation if patient deterioratesIntubation if patient deteriorates

Pharmacologic AdjunctsPharmacologic Adjuncts Pharmacologic AdjunctsPharmacologic Adjuncts

• BronchodilatorsBronchodilators

22-agonists-agonists

–Anticholinergics Anticholinergics (ipratropium)(ipratropium)

• CorticosteroidsCorticosteroids

• TheophyllineTheophylline

• AntibioticsAntibiotics

• BronchodilatorsBronchodilators

22-agonists-agonists

–Anticholinergics Anticholinergics (ipratropium)(ipratropium)

• CorticosteroidsCorticosteroids

• TheophyllineTheophylline

• AntibioticsAntibiotics

Key PointsKey PointsKey PointsKey Points