Respiratory failure : Respiratory failure Conducted by: Ms.Monika Williams Clinical instructor Army college of nursing Introduction : 2 Free template from www.brainybetty.com Introduction Respiratory failure is a broad ,non specific clinical diagnosis indicating that the respiratory sysytem is unable to supply the o2 necessary to maintain metabolism or cannot eliminate sufficient c02 . Definition (1): 3 Free template from www.brainybetty.com Definition (1) Respiratory failure is a syndrome in which the respiratory system fails in one or both of its gas exchange functions. That is oxygenation and carbon dioxide elimination In practice, respiratory failure is defined as a : - PaO2 value of less than 60 mm Hg while breathing air - PaCO2 of more than 50 mm Hg. Definition (2) : 4 Free template from www.brainybetty.com Definition (2) Respiratory failure is a syndrome of inadequate gas exchange due to dysfunction of one or more essential components of the respiratory system Chest wall (including pleura and diaphragm) Airways Alveolar– capillary units Pulmonary circulation Nerves supply to respiratory organs CNS or Brain Stem Classification of respiratory failure: 5 Classification of respiratory failure Type I or Hypoxemic (PaO2 <60 mm hg ): Failure of oxygen exchange Type II or Hypercapnic (PaCO2 >45 mm hg ): Failure to exchange or remove carbon dioxide Type III Respiratory Failure : Perioperative respiratory failure Can be resulted by anesthetic or operative technique, incentive spirometry, post-operative analgesia, Cont………….d: 6 Cont………….d Type IV Respiratory Failure : S hock Type IV describes patients who are intubated and ventilated in the process of resuscitation for shock Goal of ventilation is to stabilize gas exchange and to unload the respiratory muscles, lowering their oxygen consumption Respiratory failure can also due to shock. Hypoxemic respiratory failure (type I): 7 Free template from www.brainybetty.com Hypoxemic respiratory failure (type I) It is characterized by a PaO2 of less than 60 mm Hg. This is the most common form of respiratory failure, and it can be associated with virtually all acute diseases of the lung which generally involve fluid filling or collapse of alveolar units. Some examples of type I respiratory failure are pulmonary edema, pneumonia, and pulmonary hemorrhage Hypercapnic respiratory failure (type II): 8 Free template from www.brainybetty.com Hypercapnic respiratory failure (type II) It is characterized by a PaCO2 of more than 50 mm Hg. Hypoxemia is common in patients with hypercapnic respiratory failure who are breathing room air. Common etiologies include drug overdose, neuromuscular disease, chest wall abnormalities, and severe airway disorders (eg, asthma, chronic obstructive pulmonary disease [COPD]. Perioperative respiratory failure (Type iii): 9 Free template from www.brainybetty.com Perioperative respiratory failure (Type iii) Peri-operative respiratory failure is usually caused by atelectasis. Effective means of preventing or treating atelectasis include incentive spirometry. Classification: 10 Free template from www.brainybetty.com Classification Respiratory failure may be Acute Chronic E.g.: acute exacerbation of advanced COPD Distinctions between acute and chronic respiratory failure: 11 Free template from www.brainybetty.com Distinctions between acute and chronic respiratory failure ACUTE RESPIRATORY FAILURE Acute hypercapnic respiratory failure develops over minutes to hours. Acute respiratory failure can develop quickly and may require emergency treatment . Acute respiratory failure usually is treated in an intensive care unit CHRONIC RESPIRATORY FAILURE Chronic respiratory failure develops over several days or longer . Chronic respiratory failure develops more slowly and lasts longer. Chronic respiratory failure can be treated at home or at a long-term care center. Etiology of respiratory failure : 12 Free template from www.brainybetty.com Etiology of respiratory failure Type I respiratory failure (hypoxic) : Pneumonia pulmonary edema Acute lung injury (ALI) Acute respiratory distress syndrome (ARDS) Pulmonary embolism Atelectasis Pulmonary fibrosis Type II Respiratory Failure (hypercapnic) : 13 Type II Respiratory Failure (hypercapnic) hypoventilation Asthma Chronic obstructive pulmonary disease (COPD) Hypoxemia and hypercapnia often occur together Type III Respiratory Failure (pre-operative) : 14 Type III Respiratory Failure (pre-operative) Inadequate post- operative analgesia, upper abdominal incision Obesity, ascites Pre- operative tobacco smoking Excessive airway secretions Type IV Respiratory Failure (shock): 15 Type IV Respiratory Failure (shock) Cardiogenic shock : Cardiogenic shock is based upon an inadequate circulation of blood due to primary failure of the ventricles of the heart to function effectively Septic shock : Septic shock is a medical emergency caused by decreased tissue perfusion and oxygen delivery as a result of severe infection and sepsis , though the microbe may be systemic or localized Hypovolemic shock : Hypovolemic shock is a particular form of shock in which the heart is unable to supply enough blood to the body Clinical manifestation : Clinical manifestation Tachycardia Impaired functioning of the heart and blood vessels Inadequate blood circulation to the parts of body People with respiratory failure may appear sleepy and confused. Cyanosis Drowsiness and malfunctioning of the brain and heart Lethargy and shortness of breath Impaired mental functioning 16 Pathophysiology : 17 Pathophysiology Respiratory failure can arise from an abnormality in any of the components of the respiratory system. It includes the airways, alveoli, CNS, peripheral nervous system, respiratory muscles, and chest wall. Patients who have hypoperfusion secondary to cardiogenic, hypovolemic, or septic shock often present with respiratory failure . Diagnosis: History: 18 Diagnosis: History Sepsis suggested by fever, chills Pneumonia suggested by cough, sputum production, chest pain Pulmonary embolus suggested by sudden onset of shortness of breath or chest pain COPD exacerbation suggested by history of heavy smoking, cough, sputum production pulmonary edema suggested by chest pain, and orthopnea Cont……………..d: 19 Cont……………..d Noncardiogenic edema suggested by the presence of risk factors including sepsis, trauma, aspiration, and blood transfusions Additional exposure to toxins history may help diagnose asthma, aspiration, inhalational injury and some interstitial lung diseases Diagnosis: Physical Findings: 20 Diagnosis: Physical Findings Hypotension usually with signs of poor perfusion suggests severe sepsis Hypertension usually with signs of poor perfusion suggests pulmonary edema Wheezing suggests airway obstruction: Bronchospasm Secretions Pulmonary edema Diagnosis: Laboratory Workup: 21 Diagnosis: Laboratory Workup ABG - Quantifies level of gas exchange abnormality Identifies type and chronicity of respiratory failure Complete blood count Anemia may cause cardiogenic pulmonary edema Leukocytosis, or leukopenia suggestive of infection Cont…………..d: 22 Free template from www.brainybetty.com Cont…………..d Microbiology Respiratory cultures: sputum/tracheal aspirate Blood, urine and body fluid (e.g. pleural) cultures Diagnostic Investigations: 23 Free template from www.brainybetty.com Diagnostic Investigations Chest radiography - Identify chest wall, pleural and lung parenchymal with opacities present. Electrocardiogram - Identify arrhythmias, ischemia, ventricular dysfunction Echocardiography - Identify right and/or left ventricular dysfunction Cont…………..d: 24 Cont…………..d Pulmonary function tests/bedside spirometry Identify obstruction, restriction May be difficult to perform if critically ill Bronchoscopy Obtain biopsies Bronchoscopy may not be safe in the if critically ill Treatment : 25 Treatment Mechanical Ventilator Emergency treatment follows the principles of cardiopulmonary resuscitation . Treatment of the underlying cause is required. Endotracheal intubation and mechanical ventilation may be required. Respiratory stimulants such as doxapram may be used. Management of Respiratory Failure: 26 Management of Respiratory Failure ABC’ s or resuscitation Ensure airway is adequate Ensure adequate supplemental oxygen and assisted ventilation, if indicated Support circulation as needed Treatment of a specific cause when possible Infection: 27 Treatment of a specific cause when possible Infection Antimicrobials Airway obstruction Bronchodilators Improve cardiac function: Positive airway pressure, diuretics, vasodilators Cont…………d: Cont…………d Oxygen therapy : Humidified oxygen during administration, preventing dehydration of the mucous membranes and pulmonary secretions. Mechanical ventilation: 29 Mechanical ventilation Non-invasive: (if patient can have patent airway and is stable) Mask: usually orofacial to start Invasive - Endotracheal tube (ETT) - Tracheostomy – if upper airway is obstructed Indications for Mechanical Ventilation: Indications for Mechanical Ventilation Cardiac or respiratory arrest Tachypnea or bradypnea with respiratory fatigue Acute respiratory acidosis hypoxemia (when the PaO2 could not be maintained above 60 mm Hg) Inability to clear secretions with impaired gas exchange or excessive respiratory work 30 Goals of mechanical ventilation : Goals of mechanical ventilation Improve ventilation by stabilizing respiratory rate and tidal volume. Assistance for neural or muscle dysfunction Sedated, comatose or paralyzed patient. Intra-operative ventilation Rest respiratory muscles Correct hypoxemia Improve cardiac function 31 Nursing management : Nursing management Patients with acute respiratory failure should be closely observed for potential deterioration Monitoring may involve intermittent/continual pulse oximetry . Any changes in physiological signs should be reported promptly to the senior practitioner Pulmonary secretions: oropharyngeal/nasopharyngeal suction helps to clear secretions.