Respiratory Failure Mechanical Ventilation

1. Pathophysiology of Respiratory Pathophysiology of Respiratory Failure and Failure and Use of Mechanical Ventilation Use of Mechanical Ventilation Puneet Katyal, MBBS, MSHI Puneet Katyal, MBBS, MSHI Ognjen Gajic Ognjen Gajic, MD Mayo Clinic, Rochester, MN, USA Mayo Clinic, Rochester, MN, USA , MD

2. Definition Definition ? ?Respiratory failure is a syndrome of inadequate Respiratory failure is a syndrome of inadequate gas exchange due to dysfunction of one or more gas exchange due to dysfunction of one or more essential components of the respiratory system: essential components of the respiratory system: ? ?Chest wall (including Chest wall (including pleura and pleura and diaphragm) diaphragm) ?Airways Airways ?Alveolar Alveolar– –capillary capillary units units ? ?Pulmonary circulation Pulmonary circulation ?Nerves Nerves ?CNS or Brain Stem CNS or Brain Stem ? ? ? ?

3. Respiratory System Respiratory System Brain Spinal cord Nerves Intercostal muscles Lung: Alveolar Unit Chest wall Airway Pleura Diaphragm

4. Epidemiology Epidemiology ? ?Incidence: about 360,000 cases per year in the Incidence: about 360,000 cases per year in the United States United States ?36% die during hospitalization 36% die during hospitalization ?Morbidity and mortality rates increase with age Morbidity and mortality rates increase with age and presence of comorbidities and presence of comorbidities ? ?

5. Classification Classification ? ?Type I or Hypoxemic (PaO2 <60 at sea level): Type I or Hypoxemic (PaO2 <60 at sea level): Failure of oxygen exchange oxygen exchange ?Increased shunt fraction (Q Increased shunt fraction (Q S S /Q ? ?Due to alveolar flooding Due to alveolar flooding ?Hypoxemia refractory to supplemental oxygen Hypoxemia refractory to supplemental oxygen ?Type II or Type II or Hypercapnic Hypercapnic (PaCO2 >45): (PaCO2 >45): Failure to exchange or remove carbon dioxide exchange or remove carbon dioxide ?Decreased alveolar minute ventilation (V Decreased alveolar minute ventilation (V A ?Often accompanied by hypoxemia that corrects with Often accompanied by hypoxemia that corrects with supplemental oxygen supplemental oxygen Failure of /Q T T ) ) ? ? Failure to ? A ) ) ? ?

6. Classification Classification ? ?Type III Respiratory Failure: Type III Respiratory Failure: Perioperative failure failure ?Increased Increased atelectasis atelectasis due to low functional residual capacity due to low functional residual capacity ( (FRC FRC) in the setting of abnormal abdominal wall mechanics ) in the setting of abnormal abdominal wall mechanics ?Often results in type I or type II respiratory failure Often results in type I or type II respiratory failure ?Can be ameliorated by anesthetic or operative technique, Can be ameliorated by anesthetic or operative technique, posture incentive incentive spirometry spirometry, post , post- -operative analgesia, attempts to lower operative analgesia, attempts to lower intra intra- -abdominal pressure abdominal pressure ?Type IV Respiratory Failure: S Type IV Respiratory Failure: Shock ?Type IV describes patients who are Type IV describes patients who are intubated in the process of resuscitation for shock in the process of resuscitation for shock ?Goal of ventilation is to stabilize gas exchange and to unload t Goal of ventilation is to stabilize gas exchange and to unload the respiratory muscles, lowering their oxygen consumption respiratory muscles, lowering their oxygen consumption Perioperative respiratory respiratory ? ? posture, , ? hock ? intubated and ventilated and ventilated ? he ?

7. Classification Classification ? ?Respiratory failure may be Respiratory failure may be ?Acute Acute ?Chronic Chronic ?Acute on chronic Acute on chronic ?E.g.: acute exacerbation of advanced COPD E.g.: acute exacerbation of advanced COPD ? ? ? ?

8. Pathophysiology: Pathophysiology: Mechanisms Mechanisms ? ?Hypoxemic failure Hypoxemic failure ?Ventilation/Perfusion (V/Q) mismatch Ventilation/Perfusion (V/Q) mismatch ?Shunt Shunt ?Exacerbated by low mixed venous O2 (SvO2) Exacerbated by low mixed venous O2 (SvO2) ? ? ? ? ?Hypercapnic Hypercapnic failure ?Decreased minute ventilation (MV) relative to Decreased minute ventilation (MV) relative to demand demand ?Increased dead space ventilation Increased dead space ventilation failure ? ?

9. Pathophysiology: Pathophysiology: Etiologic Categories Etiologic Categories ?Nervous system Nervous system failure (Type II) failure (Type II) ?Central Central hypoventilation hypoventilation ?Neuropathies Neuropathies ?Muscle (pump) Muscle (pump) failure (Type II) failure (Type II) ?Muscular dystrophies Muscular dystrophies ?Myopathies Myopathies ? ?Neuromuscular Neuromuscular transmission failure transmission failure (Type II) (Type II) ?Myasthenia gravis Myasthenia gravis ?Airway failure Airway failure (Type II) (Type II) ?Obstruction Obstruction ?Dysfunction Dysfunction ? ? ? ? ? ? ? ? ? ?

10. Pathophysiology: Pathophysiology: Etiologic Categories Etiologic Categories ? ?Chest wall and pleural Chest wall and pleural space failure (Type II) space failure (Type II) ?Kyphoscoliosis Kyphoscoliosis ?Morbid obesity Morbid obesity ?Pneumothorax Pneumothorax ?Hydrothorax Hydrothorax ?Hemothorax Hemothorax ? ?Alveolar unit failure Alveolar unit failure (Type I) (Type I) ?Collapse Collapse ?Flooding: edema, blood, Flooding: edema, blood, pus, aspiration pus, aspiration ?Fibrosis Fibrosis ? ? ? ? ? ? ? ? ? ?Pulmonary vasculature failure (Type I) Pulmonary vasculature failure (Type I) ?Pulmonary embolism Pulmonary embolism ?Pulmonary hypertension Pulmonary hypertension ? ?

11. Causes Causes ? ?Type I respiratory failure Type I respiratory failure ?Pneumonia Pneumonia ?Cardiogenic Cardiogenic pulmonary edema ?Pulmonary edema due to increased hydrostatic pressure Pulmonary edema due to increased hydrostatic pressure ?Non Non- -cardiogenic pulmonary edema cardiogenic pulmonary edema ?Pulmonary edema due to increased permeability Pulmonary edema due to increased permeability ?Acute lung injury (ALI) Acute lung injury (ALI) ?Acute respiratory distress syndrome (ARDS) Acute respiratory distress syndrome (ARDS) ?Pulmonary embolism (see also type IV respiratory failure) Pulmonary embolism (see also type IV respiratory failure) ?Atelectasis (see also type III respiratory failure) Atelectasis (see also type III respiratory failure) ?Pulmonary fibrosis Pulmonary fibrosis ? pulmonary edema ? ? ? ? ? ? ? ? ?

12. Causes Causes ? ?Type II respiratory failure Type II respiratory failure ?Central hypoventilation Central hypoventilation ?Asthma Asthma ?Chronic obstructive pulmonary disease (COPD) Chronic obstructive pulmonary disease (COPD) ?Hypoxemia and Hypoxemia and hypercapnia hypercapnia often occur together ? ? ? often occur together ? *Neuromuscular and chest wall disorders Neuromuscular and chest wall disorders ?Myopathies Myopathies ?Neuropathies Neuropathies ?Kyphoscoliosis Kyphoscoliosis ?Myasthenia gravis Myasthenia gravis ?Obesity Hypoventilation Syndrome Obesity Hypoventilation Syndrome ? ? ? ? ?

13. Causes Causes ? ?Type III respiratory failure Type III respiratory failure ?Inadequate post Inadequate post- -operative analgesia, upper abdominal operative analgesia, upper abdominal incision incision ?Obesity, Obesity, ascites ascites ?Pre Pre- -operative tobacco smoking operative tobacco smoking ?Excessive airway secretions Excessive airway secretions ?Type IV respiratory failure Type IV respiratory failure ?Cardiogenic Cardiogenic shock shock ?Septic shock Septic shock ?Hypovolemic Hypovolemic shock shock ? ? ? ? ? ? ? ?

14. Diagnosis: History Diagnosis: History ? ?Sepsis suggested by fever, chills Sepsis suggested by fever, chills ?Pneumonia suggested by cough, sputum production, Pneumonia suggested by cough, sputum production, chest pain chest pain ?Pulmonary embolus suggested by sudden onset of Pulmonary embolus suggested by sudden onset of shortness of breath or chest pain shortness of breath or chest pain ?COPD exacerbation suggested by history of heavy COPD exacerbation suggested by history of heavy smoking, cough, sputum production smoking, cough, sputum production ?Cardiogenic pulmonary edema suggested by chest pain, Cardiogenic pulmonary edema suggested by chest pain, paroxysmal nocturnal dyspnea, and orthopnea paroxysmal nocturnal dyspnea, and orthopnea ? ? ? ?

15. Diagnosis: History Diagnosis: History Noncardiogenic edema suggested by the presence of risk factors including sepsis, presence of risk factors including sepsis, trauma, aspiration, and blood transfusions trauma, aspiration, and blood transfusions ?Accompanying sensory abnormalities or Accompanying sensory abnormalities or symptoms of weakness may suggest symptoms of weakness may suggest neuromuscular respiratory failure; as would the neuromuscular respiratory failure; as would the history of an ingestion or administration of history of an ingestion or administration of drugs or toxins. drugs or toxins. ?Additional exposure history may help diagnose Additional exposure history may help diagnose asthma, aspiration, inhalational injury and some asthma, aspiration, inhalational injury and some interstitial lung diseases interstitial lung diseases ? ?Noncardiogenic edema suggested by the ? ?

16. Diagnosis: Physical Findings Diagnosis: Physical Findings ? ?Hypotension usually with signs of poor perfusion Hypotension usually with signs of poor perfusion suggests severe sepsis or massive pulmonary embolus suggests severe sepsis or massive pulmonary embolus ?Hypertension usually with signs of poor perfusion Hypertension usually with signs of poor perfusion suggests cardiogenic pulmonary edema suggests cardiogenic pulmonary edema ?Wheezing suggests airway obstruction: Wheezing suggests airway obstruction: ?Bronchospasm Bronchospasm ?Fixed upper or lower airway pathology Fixed upper or lower airway pathology ?Secretions Secretions ?Pulmonary edema ( Pulmonary edema (“ “cardiac asthma cardiac asthma” ”) ) ? ? ? ? ? ?

17. Diagnosis: Physical Findings Diagnosis: Physical Findings ? ?Stridor suggests upper airway obstruction Stridor suggests upper airway obstruction ?Elevated jugular venous pressure suggests right Elevated jugular venous pressure suggests right ventricular dysfunction due to accompanying ventricular dysfunction due to accompanying pulmonary hypertension pulmonary hypertension ?Tachycardia and arrhythmias may be the cause Tachycardia and arrhythmias may be the cause of cardiogenic pulmonary edema of cardiogenic pulmonary edema ? ?

18. Diagnosis: Laboratory Workup Diagnosis: Laboratory Workup ? ?ABG ABG ?Quantifies magnitude of gas exchange abnormality Quantifies magnitude of gas exchange abnormality ?Identifies type and chronicity of respiratory failure Identifies type and chronicity of respiratory failure ?Complete blood count Complete blood count ?Anemia may cause cardiogenic pulmonary edema Anemia may cause cardiogenic pulmonary edema ?Polycythemia suggests may chronic hypoxemia Polycythemia suggests may chronic hypoxemia ?Leukocytosis, a left shift, or leukopenia suggestive of Leukocytosis, a left shift, or leukopenia suggestive of infection infection ?Thrombocytopenia may suggest sepsis as a cause Thrombocytopenia may suggest sepsis as a cause ? ? ? ? ? ? ?

19. Diagnosis: Laboratory Workup Diagnosis: Laboratory Workup ? ?Cardiac serologic markers Cardiac serologic markers ?Troponin, Creatine kinase Troponin, Creatine kinase- - MB fraction (CK ?B B- -type natriuretic peptide (BNP) type natriuretic peptide (BNP) MB fraction (CK- -MB) MB) ? ? ? ?Microbiology Microbiology ?Respiratory cultures: sputum/tracheal Respiratory cultures: sputum/tracheal aspirate/ aspirate/broncheoalveolar broncheoalveolar lavage (BAL) ?Blood, urine and body fluid (e.g. pleural) cultures Blood, urine and body fluid (e.g. pleural) cultures ? lavage (BAL) ?

20. Diagnostic Investigations Diagnostic Investigations Chest radiography Identify chest wall, pleural and lung parenchymal pathology; and distinguish disorders that cause pathology; and distinguish disorders that cause primarily V/Q mismatch (clear lungs) vs. Shunt primarily V/Q mismatch (clear lungs) vs. Shunt (intra (intra- -pulmonary shunt; with opacities present) pulmonary shunt; with opacities present) ?Electrocardiogram Electrocardiogram ?Identify arrhythmias, ischemia, ventricular Identify arrhythmias, ischemia, ventricular dysfunction dysfunction ?Echocardiography Echocardiography ?Identify right and/or left ventricular dysfunction Identify right and/or left ventricular dysfunction ? ?Chest radiography ?Identify chest wall, pleural and lung parenchymal ? ? ? ? ?

21. Diagnostic Investigations Diagnostic Investigations ? ?Pulmonary function tests/bedside spirometry Pulmonary function tests/bedside spirometry ?Identify obstruction, restriction, gas diffusion abnormalities Identify obstruction, restriction, gas diffusion abnormalities ?May be difficult to perform if critically ill May be difficult to perform if critically ill ?Bronchoscopy Bronchoscopy ?Obtain biopsies, brushings and BAL for histology, cytology Obtain biopsies, brushings and BAL for histology, cytology and microbiology and microbiology ?Results may not be available quickly enough to avert Results may not be available quickly enough to avert respiratory failure respiratory failure ?Bronchoscopy may not be safe in the Bronchoscopy may not be safe in the if critically ill ? ? ? ? ? if critically ill ?

22. Respiratory Failure: Respiratory Failure: Management Management ? ?ABC ABC’ ’s s ?Ensure airway is adequate Ensure airway is adequate ?Ensure adequate supplemental oxygen and assisted Ensure adequate supplemental oxygen and assisted ventilation, if indicated ventilation, if indicated ?Support circulation as needed Support circulation as needed ? ? ?

23. Respiratory Failure: Respiratory Failure: Management Management Treatment of a specific cause when possible ?Infection Infection ?Antimicrobials, source control Antimicrobials, source control ?Airway obstruction Airway obstruction ?Bronchodilators, glucocorticoids Bronchodilators, glucocorticoids ?Improve cardiac function Improve cardiac function ?Positive airway pressure, diuretics, vasodilators, Positive airway pressure, diuretics, vasodilators, morphine, morphine, inotropy inotropy, revascularization , revascularization ? ?Treatment of a specific cause when possible ? ? ? ? ? ?

24. Respiratory Failure: Respiratory Failure: Management Management Mechanical ventilation Non- -invasive (if patient can protect airway and is invasive (if patient can protect airway and is hemodynamically stable) hemodynamically stable) ?Mask: usually orofacial to start Mask: usually orofacial to start ?Invasive Invasive ?Endotracheal tube (ETT) Endotracheal tube (ETT) ?Tracheostomy Tracheostomy – – if upper airway is obstructed if upper airway is obstructed ? ?Mechanical ventilation ?Non ? ? ? ? ?

25. Respiratory Failure Secure airway Need for endotracheal intubation or tracheostomy? Supplemental oxygen as needed Treat underlying condition Yes No Invasive mechanical ventilation Non-invasive mechanical ventilation Fails

26. Indications for Mechanical Indications for Mechanical Ventilation Ventilation ? ?Cardiac or respiratory arrest Cardiac or respiratory arrest ?Tachypnea or bradypnea with respiratory fatigue or Tachypnea or bradypnea with respiratory fatigue or impending arrest impending arrest ?Acute respiratory acidosis Acute respiratory acidosis ?Refractory hypoxemia Refractory hypoxemia (when the P a O 2 could not be maintained above 60 mm Hg with inspired O 2 fraction (F I O 2 )>1.0) ?Inability to protect the airway associated with depressed levels Inability to protect the airway associated with depressed levels of consciousness of consciousness ? ? ? ?

27. Indications for Mechanical Indications for Mechanical Ventilation Ventilation ? ?Shock associated with excessive respiratory work Shock associated with excessive respiratory work ?Inability to clear secretions with impaired gas exchange Inability to clear secretions with impaired gas exchange or excessive respiratory work or excessive respiratory work ?Newly diagnosed neuromuscular disease with a vital Newly diagnosed neuromuscular disease with a vital capacity <10 capacity <10- -15 mL/kg 15 mL/kg ?Short term adjunct in management of acutely increased Short term adjunct in management of acutely increased intracranial pressure (ICP) intracranial pressure (ICP) ? ? ?

28. Invasive vs. Non Invasive vs. Non- -invasive Ventilation Ventilation invasive ? ?Consider non Consider non- -invasive ventilation particularly invasive ventilation particularly in the following settings: in the following settings: ?COPD exacerbation COPD exacerbation ?Cardiogenic pulmonary edema Cardiogenic pulmonary edema ?Obesity hypoventilation syndrome Obesity hypoventilation syndrome ?Noninvasive ventilation may be tried in selected Noninvasive ventilation may be tried in selected patients with asthma or non patients with asthma or non- -cardiogenic hypoxemic respiratory failure respiratory failure ? ? ? ? cardiogenic hypoxemic

29. Goals of Mechanical Goals of Mechanical Ventilation Ventilation ?Improve ventilation by augmenting respiratory Improve ventilation by augmenting respiratory rate and tidal volume rate and tidal volume ?Assistance for neural or muscle dysfunction Assistance for neural or muscle dysfunction ?Sedated, comatose or paralyzed patient Sedated, comatose or paralyzed patient ?Neuropathy, myopathy or muscular dystrophy Neuropathy, myopathy or muscular dystrophy ?Intra Intra- -operative ventilation operative ventilation ?Correct respiratory acidosis, providing goals of lung Correct respiratory acidosis, providing goals of lung- - protective ventilation are met protective ventilation are met ?Match metabolic demand Match metabolic demand ?Rest respiratory muscles Rest respiratory muscles ? ? ? ? ? ? ? ?

30. Goals of Mechanical Goals of Mechanical Ventilation Ventilation ? ?Correct hypoxemia Correct hypoxemia ?High F High F I I O ? ?Positive end expiratory pressure (PEEP) Positive end expiratory pressure (PEEP) O 2 2 ? ? ?Improve cardiac function Improve cardiac function ?Decreases preload Decreases preload ?Decreases afterload Decreases afterload ?Decreases metabolic demand Decreases metabolic demand ? ? ?

31. Permissive Hypercapnia Permissive Hypercapnia ? ?Ventilation strategy that allows P Ventilation strategy that allows P a a CO by accepting a lower alveolar minute ventilation by accepting a lower alveolar minute ventilation to avoid specific risks: to avoid specific risks: ?Dynamic hyperinflation ( Dynamic hyperinflation (“ “auto barotrauma in patients with asthma barotrauma in patients with asthma ?Ventilator Ventilator- -associated lung injury, in patients with, or associated lung injury, in patients with, or at risk for, ALI and ARDS at risk for, ALI and ARDS CO 2 2 to rise to rise auto- -peep peep” ”) and ) and ? ? ? ?Contraindicated in patients with increased Contraindicated in patients with increased intracranial pressure such as head trauma intracranial pressure such as head trauma

32. Mechanical Ventilation Preload, Afterload, F I O 2 , PEEP Metabolic demand RR, TV Correct Hypoxemia Enhance Ventilation * Optimize cardiac function Meet increased metabolic demand Correct respiratory acidosis* Assistance for neural and/or muscle dysfunction Hyperventilation may be used as a short term adjunct to treat acutely elevated ICP * Avoid ventilator induced lung injury and dynamic hyperinflation

33. Other Issues to Consider When Other Issues to Consider When Initiating Mechanical Ventilation Initiating Mechanical Ventilation ? ?Do not wait for frank respiratory acidosis Do not wait for frank respiratory acidosis especially with evidence of: especially with evidence of: ?Inability to protect airway Inability to protect airway ?Persistent or worsening tachypnea (respiratory rate Persistent or worsening tachypnea (respiratory rate >35/minute) >35/minute) ?Respiratory muscle fatigue Respiratory muscle fatigue ?Always consider risks and benefits of initiation Always consider risks and benefits of initiation and continuation of mechanical ventilation and continuation of mechanical ventilation ? ? ? ?

34. Other Issues in Intubated & Other Issues in Intubated & Mechanically Ventilated Mechanically Ventilated Patients Patients ? ?Always elevate the head of the bed >30 Always elevate the head of the bed >30º º and use ulcer and DVT prophylaxis, unless contraindicated and DVT prophylaxis, unless contraindicated ?Use lung protective ventilation strategy for patients Use lung protective ventilation strategy for patients with Acute Lung Injury (TV ~ 6 ml/kg ideal body with Acute Lung Injury (TV ~ 6 ml/kg ideal body weight, Plat pressure < 30 cmH weight, Plat pressure < 30 cmH 2 2 O) ? ?Modify ventilator settings primarily to achieve patient Modify ventilator settings primarily to achieve patient- - ventilator synchrony. If this fails, use the least amount ventilator synchrony. If this fails, use the least amount of sedation required to achieve comfort and avoid of sedation required to achieve comfort and avoid unnecessary neuromuscular blockade unnecessary neuromuscular blockade and use ulcer ? O)

35. Other Issues in Intubated & Other Issues in Intubated & Mechanically Ventilated Mechanically Ventilated Patients Patients ? ?Monitor patient comfort, gas exchange, Monitor patient comfort, gas exchange, mechanics, and ventilator waveforms daily, or mechanics, and ventilator waveforms daily, or more frequently if indicated more frequently if indicated ? ?When minimal settings are required for When minimal settings are required for oxygenation (F oxygenation (F I I O O 2 2 <55%, PEEP<8) and <55%, PEEP<8) and patient is hemodynamically stable, perform a patient is hemodynamically stable, perform a spontaneous breathing trial daily spontaneous breathing trial daily

36. References References ? ?Arora Arora,V.K., 1, p 32 1, p 32- -34. ? ?Behrendt Behrendt C.F. (2000). Acute respiratory failure in the United States: Inc C.F. (2000). Acute respiratory failure in the United States: Incidence and 31 31- -day survival. day survival. Chest, Volume 118, Number 4, p 1100 Chest, Volume 118, Number 4, p 1100- -1105. ? ?Brochard Brochard L., L., Mancebo Mancebo J., Elliott M.W. (2002). Noninvasive ventilation for acute J., Elliott M.W. (2002). Noninvasive ventilation for acute respiratory failure. respiratory failure. European Respiratory Journal, Volume 19, Number 4, p 712 European Respiratory Journal, Volume 19, Number 4, p 712- -721 ? ?Hall J.B., Schmidt G.A, Wood L. D.H. (2005). Hall J.B., Schmidt G.A, Wood L. D.H. (2005). Principles of Critical Care, 3rd Edition. New York: McGraw New York: McGraw- -Hill Professional. Hill Professional. ? ?http://upload.wikimedia.org/wikipedia/en/thumb/d/db/Alveoli_diag http://upload.wikimedia.org/wikipedia/en/thumb/d/db/Alveoli_diagram.png/300px Alveoli_diagram.png Alveoli_diagram.png. Retrieved Nov., 16, 2006 from http://www. . Retrieved Nov., 16, 2006 from http://www.wikimedia ? ?Hurford Hurford W.E. (2002). Sedation and paralysis during mechanical ventilatio W.E. (2002). Sedation and paralysis during mechanical ventilation. Car, Volume 47, Number 3, p 334 Car, Volume 47, Number 3, p 334- -346. 346. ? ?Kasper D.L, Braunwald E., Kasper D.L, Braunwald E., Fauci Fauci A.S., Hauser S.L., Longo D.L., Jameson J.L., A.S., Hauser S.L., Longo D.L., Jameson J.L., Isselbacher Isselbacher, K.L. (2004). , K.L. (2004).Harrison's Principles of Internal Medicine, 16th Edition. Harrison's Principles of Internal Medicine, 16th Edition. New York: McGraw McGraw- -Hill Professional. Hill Professional. ? ?Masip J., Roque M., Sa Masip J., Roque M., Sa´ ´nchez B., Ferna nchez B., Ferna´ ´ndez R., Subirana M., Expo ndez R., Subirana M., Expo´ ´ sito J.A., (2005). Noninvasive Ventilation in Acute Cardiogenic Pulmonary Edema: Sy Noninvasive Ventilation in Acute Cardiogenic Pulmonary Edema: Systematic Review and Meta and Meta- -analysis. analysis. Journal of the American Medical Association, Volume 294, Number Journal of the American Medical Association, Volume 294, Number 24, p 3124 3124- -3130. 3130. ? ?Michael E. Hanley M.E., Welsh, C.H. (2003). Michael E. Hanley M.E., Welsh, C.H. (2003). Current Diagnosis & Treatment in Pulmonary Medicine. Pulmonary Medicine. New York: McGraw New York: McGraw- -Hill Professional. Hill Professional. ,V.K., Shankar Shankar, U. (1995). Acute Lung Injury. , U. (1995). Acute Lung Injury. Lung India, Volume 34. Lung India, Volume XIII, XIII, Number Number idence and 1105. 721 Principles of Critical Care, 3rd Edition. ram.png/300px- - wikimedia.org. .org. n. Respiratory Respiratory New York: sito J.A., (2005). stematic Review 24, p Current Diagnosis & Treatment in

37. References References ? ?Midelton Midelton G.T., continuous positive airway pressure therapy: support of a new mo continuous positive airway pressure therapy: support of a new modality for improving the prognosis and survival of patients with advanced congestive the prognosis and survival of patients with advanced congestive heart failure. Disease, Volume 4 Disease, Volume 4, , Number 2, p 102 Number 2, p 102- -109 109. . ?Plant P., Owen J., Elliott M. (2000). Early use of non Plant P., Owen J., Elliott M. (2000). Early use of non- -invasive ventilation for acute exacerbations of chronic obstructive pulmonary disease on genera exacerbations of chronic obstructive pulmonary disease on general respiratory wards: a a multicentre randomised multicentre randomised controlled trial. controlled trial. The Lancet, Volume 355, Issue 9219, p 1931 1935 1935. . ?Ryland Ryland B.P., Jr. B.P., Jr. emedicine emedicine- - Ventilation, Mechanical Ventilation, Mechanical. Retrieved Nov., 24, 2006 from http://www.emedicine.com/med/topic3370.htm http://www.emedicine.com/med/topic3370.htm ?Sharma S. Sharma S. emedicine emedicine- -Respiratory Failure Respiratory Failure. Retrieved Nov., 24, 2006 from . Retrieved Nov., 24, 2006 from http://www.emedicine.com/med/topic2011.htm http://www.emedicine.com/med/topic2011.htm ?The Acute Respiratory Distress Syndrome Network (2000). Ventilat The Acute Respiratory Distress Syndrome Network (2000). Ventilation with lower tidal volumes as compared with traditional tidal volumes for acu tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome. acute respiratory distress syndrome. New England Journal of Medicine, Volume 342, New England Journal of Medicine, Volume 342, Number 18, p 1301 Number 18, p 1301- -1308. 1308. ?Tobin, M.J. Tobin, M.J. Principles and Practice of Mechanical Ventilation, 2nd Edition ( Principles and Practice of Mechanical Ventilation, 2nd Edition (2006). McGraw McGraw- -Hill Hill Medical Publishing Division. Medical Publishing Division. G.T., Frishman Frishman W.H., W.H., Passo Passo S.S. (2002). Congestive heart failure and S.S. (2002). Congestive heart failure and dality for improving heart failure. Heart Heart invasive ventilation for acute l respiratory wards: The Lancet, Volume 355, Issue 9219, p 1931- - ? . Retrieved Nov., 24, 2006 from ? ? ion with lower te lung injury and the ? 2006). New York: New York: ?