Acute respiratory distress syndrome - Revision history

Aidan: /* Management */

2021-08-29T02:30:32Z

Management

← Older revision		Revision as of 02:30, 29 August 2021
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	** Targets tidal volume of 6mL/kg predicted body weight, plateau pressure ≤30 cmH2O, SpO2 88-95%, and pH 7.3-7.45		** Targets tidal volume of 6mL/kg predicted body weight, plateau pressure ≤30 cmH2O, SpO2 88-95%, and pH 7.3-7.45
	** Decrease tidal volume from 8mL/kg to 6mL/kg predicted body weight over 4 hours, then continue to decrease in 1 mL/kg increments until plateau pressures <30 or tidal volume 4mL/kg		** Decrease tidal volume from 8mL/kg to 6mL/kg predicted body weight over 4 hours, then continue to decrease in 1 mL/kg increments until plateau pressures <30 or tidal volume 4mL/kg
	** PEEP over 15 cmH<sub><s>2</s></sub>O [https://doi.org/10.1001/jama.2010.218 may be protective in severe ARDS]
⚫	** Permissive hypercapnia to CO<sub>2</sub> 60-70 and pH 7.2-7.25, if needed
	* Maintain euvolemia		* Maintain euvolemia

			=== Moderate to Severe ARDS ===

			* Higher PEEP over 15 cmH<sub>2</sub>O
		⚫	* Permissive hypercapnia to CO<sub>2</sub> 60-70 and pH 7.2-7.25, if needed

	=== Severe ARDS ===		=== Severe ARDS ===

Aidan at 02:28, 29 August 2021

2021-08-29T02:28:41Z

← Older revision		Revision as of 02:28, 29 August 2021
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	== ~~Summary~~ ==		== Background ==

	* Lung damage that occurs within one week of an insult, with bilateral CXR opacities, not explain by other causes		* Lung damage that occurs within one week of an insult, with bilateral CXR opacities, not explain by other causes
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	** V<s>T</s> 6mL/kg predicted body weight, plateau pressure ≤30 cmH<s>2</s>O, SpO2 88-95%, and pH 7.3-7.45		** V<s>T</s> 6mL/kg predicted body weight, plateau pressure ≤30 cmH<s>2</s>O, SpO2 88-95%, and pH 7.3-7.45

	== Definition ==		=== Definition ===

	* Syndrome of diffuse alveolar and interstitial edema		* Syndrome of diffuse alveolar and interstitial edema
	* "[https://doi.org/10.1007/s00134-005-2627-z Baby lung]": small effective lung volume, because the dependent portions are filled with fluid		* "[https://doi.org/10.1007/s00134-005-2627-z Baby lung]": small effective lung volume, because the dependent portions are filled with fluid

	== [https://doi.org/10.1001/jama.2012.5669 Berlin Definition (2012)] ==		===[https://doi.org/10.1001/jama.2012.5669 Berlin Definition (2012)]===

	* Syndrome, not disease, per European task force in 2012		* Syndrome, not disease, per European task force in 2012
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	* Chest imaging bilateral opacities not otherwise explained		* Chest imaging bilateral opacities not otherwise explained
	* Severity based on oxygenation		* Severity based on oxygenation
	** Mild: ratio of PaO<s>2</s>/FiO<s>2</s> between 200-300 with PEEP over 5 cmH<s>2</s>O (27% mortality)		** Mild: ratio of PaO<sub>2</sub>/FiO<sub>2</sub> between 200-300 with PEEP over 5 cmH<sub>2</sub>O (27% mortality)
	** Moderate: ratio between 100 and 200 with PEEP over 5 cmH<s>2</s>O (32% mortality)		** Moderate: ratio between 100 and 200 with PEEP over 5 cmH<sub>2</sub>O (32% mortality)
	** Severe: ratio below 100 with PEEP over 5 cmH<s>2</s>O (45% mortality)		** Severe: ratio below 100 with PEEP over 5 cmH<sub>2</sub>O (45% mortality)

	== ~~Causes~~ ==		=== Etiologies ===

	* Direct		* Direct
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	** Amniotic fluid embolism		** Amniotic fluid embolism

	== Pathophysiology ==		=== Pathophysiology ===

	* Acute edema from neutrophil activation, with formation of hyaline membranes, and eventual fibrosis		* Acute edema from neutrophil activation, with formation of hyaline membranes, and eventual fibrosis
	* Type I pneumocytes replaced with type II		* Type I pneumocytes replaced with type II
			* Increased alveolar permeability leading to non-hydrostatic pulmonary edema
	* Lungs become less compliant, due to a decrease in the available lung volume		* Lungs become less compliant, due to a decrease in the available lung volume

		⚫	== Clinical Manifestations ==

		⚫	* Dyspnea and escalating ventilatory requirements following a known cause of ARDS

	== Differential Diagnosis ==		== Differential Diagnosis ==

	* ARDS (50%)		* ARDS (50%)
	* Pneumonia (25%)		* [[Pneumonia]] (25%)
	* Pulmonary edema (11%)		* [[Pulmonary edema]] (11%)
	* Invasive aspergillosis (6%)		* [[Invasive aspergillosis]] (6%)
	* Pulmonary embolism (3%)		* [[Pulmonary embolism]] (3%)
	* Other (5%)		* Other (5%)

⚫	== Clinical Manifestations ==

⚫	* Dyspnea and escalating ventilatory requirements following a known cause of ARDS

	== Investigations ==		== Investigations ==
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	== Management ==		== Management ==

			=== All Patients ===
	* Lung-protective ventilation (see [[ARDS ventilation protocol]])		* Lung-protective ventilation (see [[ARDS ventilation protocol]])
	** Targets tidal volume of 6mL/kg predicted body weight, plateau pressure ≤30 cmH2O, SpO2 88-95%, and pH 7.3-7.45		** Targets tidal volume of 6mL/kg predicted body weight, plateau pressure ≤30 cmH2O, SpO2 88-95%, and pH 7.3-7.45
	** Decrease tidal volume from 8mL/kg to 6mL/kg predicted body weight over 4 hours, then continue to decrease in ~~1mL~~/kg increments until plateau pressures <30 or tidal volume 4mL/kg		** Decrease tidal volume from 8mL/kg to 6mL/kg predicted body weight over 4 hours, then continue to decrease in 1 mL/kg increments until plateau pressures <30 or tidal volume 4mL/kg
	** PEEP over 15 cmH<s>2</s>O [https://doi.org/10.1001/jama.2010.218 may be protective in severe ARDS]		** PEEP over 15 cmH<sub><s>2</s></sub>O [https://doi.org/10.1001/jama.2010.218 may be protective in severe ARDS]
	** Permissive hypercapnia to ~~CO2~~ 60-70 and pH 7.2-7.25, if needed		** Permissive hypercapnia to CO<sub>2</sub> 60-70 and pH 7.2-7.25, if needed
⚫	* Prone positioning
	* Maintain euvolemia		* Maintain euvolemia

			=== Severe ARDS ===

		⚫	* Prone positioning
			* vv-[[ECMO]]

	[[Category:Critical care]]		[[Category:Critical care]]

Aidan: Text replacement - "Clinical Presentation" to "Clinical Manifestations"

2020-07-19T13:32:15Z

Text replacement - "Clinical Presentation" to "Clinical Manifestations"

← Older revision		Revision as of 13:32, 19 July 2020
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	* Other (5%)		* Other (5%)

	== Clinical ~~Presentation~~ ==		== Clinical Manifestations ==

	* Dyspnea and escalating ventilatory requirements following a known cause of ARDS		* Dyspnea and escalating ventilatory requirements following a known cause of ARDS

Maintenance script: Imported from text file

2020-07-04T01:17:21Z

Imported from text file

New page

== Summary ==

* Lung damage that occurs within one week of an insult, with bilateral CXR opacities, not explain by other causes
* Severity based on P:F ratio: severe <100, moderate 100-200, and mild 200-300
* Lung protective ventilation [https://doi.org/10.1056/NEJM200005043421801 reduces mortality]
** V<s>T</s> 6mL/kg predicted body weight, plateau pressure ≤30 cmH<s>2</s>O, SpO2 88-95%, and pH 7.3-7.45

== Definition ==

* Syndrome of diffuse alveolar and interstitial edema
* "[https://doi.org/10.1007/s00134-005-2627-z Baby lung]": small effective lung volume, because the dependent portions are filled with fluid

== [https://doi.org/10.1001/jama.2012.5669 Berlin Definition (2012)] ==

* Syndrome, not disease, per European task force in 2012
* Timing: within 1 week of a known insult
* Origin of edema: not cardiac or hydrostatic edema
* Chest imaging bilateral opacities not otherwise explained
* Severity based on oxygenation
** Mild: ratio of PaO<s>2</s>/FiO<s>2</s> between 200-300 with PEEP over 5 cmH<s>2</s>O (27% mortality)
** Moderate: ratio between 100 and 200 with PEEP over 5 cmH<s>2</s>O (32% mortality)
** Severe: ratio below 100 with PEEP over 5 cmH<s>2</s>O (45% mortality)

== Causes ==

* Direct
** Pneumonia
** Aspiration
** Inhalational injury
** Pulmonary contusion
** Near-drowning
* Indirection
** Sepsis
** Major trauma
** Multiple blood product transfusions
** Pancreatitis
** Shock
** Drug overdose
** Amniotic fluid embolism

== Pathophysiology ==

* Acute edema from neutrophil activation, with formation of hyaline membranes, and eventual fibrosis
* Type I pneumocytes replaced with type II
* Lungs become less compliant, due to a decrease in the available lung volume

== Differential Diagnosis ==

* ARDS (50%)
* Pneumonia (25%)
* Pulmonary edema (11%)
* Invasive aspergillosis (6%)
* Pulmonary embolism (3%)
* Other (5%)

== Clinical Presentation ==

* Dyspnea and escalating ventilatory requirements following a known cause of ARDS

== Investigations ==

* Chest x-ray showing bilateral infiltrates
* Bronchoalveolar lavage (BAL)
** Excludes the diagnosis if less than 5% neutrophils (can be over 80% in ARDS)
** Suggestive if lavage to plasma protein ratio > 0.7 (less than 0.5 in hydrostatic edema)

== Management ==

* Lung-protective ventilation (see [[ARDS ventilation protocol]])
** Targets tidal volume of 6mL/kg predicted body weight, plateau pressure ≤30 cmH2O, SpO2 88-95%, and pH 7.3-7.45
** Decrease tidal volume from 8mL/kg to 6mL/kg predicted body weight over 4 hours, then continue to decrease in 1mL/kg increments until plateau pressures <30 or tidal volume 4mL/kg
** PEEP over 15 cmH<s>2</s>O [https://doi.org/10.1001/jama.2010.218 may be protective in severe ARDS]
** Permissive hypercapnia to CO2 60-70 and pH 7.2-7.25, if needed
* Prone positioning
* Maintain euvolemia

[[Category:Critical care]]
[[Category:Respirology]]