1. 1 Diagnosis and Management of Acute Respiratory Failure ® Steven B. Leven, M.D., F.C.C.P. Clinical Professor, Pulmonary/Critical Care Medicine UCI Director MICU and Respiratory Therapy, UCI Medical Center

2. Objectives Understand the causes of hypoxia and hypercapnea Understand the causes of hypoxia and hypercapnea Know the clinical manifestations of respiratory failure Know the clinical manifestations of respiratory failure Be familiar with various oxygen delivery systems Be familiar with various oxygen delivery systems Know indications and contraindications to noninvasive positive pressure ventilation Know indications and contraindications to noninvasive positive pressure ventilation Know indications for endotracheal intubation Know indications for endotracheal intubation Be familiar with basic modes of mechanical ventilation Be familiar with basic modes of mechanical ventilation 2

3. 3 CASE # 1 J.T. is a 68-kg, 42-yr old female admitted after a drug overdose complicated by emesis and aspiration. Intubation and mechanical ventilation are initiated in the emergency department. J.T. is a 68-kg, 42-yr old female admitted after a drug overdose complicated by emesis and aspiration. Intubation and mechanical ventilation are initiated in the emergency department.

4. 4 CASE # 1 CASE # 1 Mechanical ventilation Mechanical ventilation – AC (volume) mode – Tidal volume 750 mL – 16 breaths/min – F IO 2 1.0 – PEEP 5 cm H 2 O Mechanical ventilation Mechanical ventilation – AC (volume) mode – Tidal volume 750 mL – 16 breaths/min – F IO 2 1.0 – PEEP 5 cm H 2 O

5. 5 CASE # 1 CASE # 1 Peak airway pressure 52 cm H 2 O Peak airway pressure 52 cm H 2 O Inspiratory plateau pressure (IPP) 48 cm H 2 O Inspiratory plateau pressure (IPP) 48 cm H 2 O pH 7.38, Pa CO 2 36 Pa O 2 57 pH 7.38, Pa CO 2 36 Pa O 2 57 Sinus tach at 166, BP 75/50, no urine output Sinus tach at 166, BP 75/50, no urine output Patient very “agitated” and “fighting vent” Patient very “agitated” and “fighting vent” What would you do? What would you do?

6. 6 CASE #2 L.W. is a 62-yr-old, 52-kg female with severe emphysema. For 2 days she has had progressive dyspnea and was found unresponsive. ABG on 5liters NC pH 7.07 pCO2 87 pO2 62. L.W. is a 62-yr-old, 52-kg female with severe emphysema. For 2 days she has had progressive dyspnea and was found unresponsive. ABG on 5liters NC pH 7.07 pCO2 87 pO2 62. She required intubation and initiation of mechanical ventilation. She required intubation and initiation of mechanical ventilation. L.W. is a 62-yr-old, 52-kg female with severe emphysema. For 2 days she has had progressive dyspnea and was found unresponsive. ABG on 5liters NC pH 7.07 pCO2 87 pO2 62. L.W. is a 62-yr-old, 52-kg female with severe emphysema. For 2 days she has had progressive dyspnea and was found unresponsive. ABG on 5liters NC pH 7.07 pCO2 87 pO2 62. She required intubation and initiation of mechanical ventilation. She required intubation and initiation of mechanical ventilation.

7. 7 CASE #2 ICU ventilator settings AC, rate 12 breaths/min AC, rate 12 breaths/min Tidal volume 500 mL Tidal volume 500 mL F IO 2 100% F IO 2 100% PEEP 5 cm H 2 O PEEP 5 cm H 2 O ICU ventilator settings AC, rate 12 breaths/min AC, rate 12 breaths/min Tidal volume 500 mL Tidal volume 500 mL F IO 2 100% F IO 2 100% PEEP 5 cm H 2 O PEEP 5 cm H 2 O

8. 8 CASE #2 RR 24 RR 24 I:E ratio = 1:1.5 I:E ratio = 1:1.5 Peak pressure 50 cm H 2 O, IPP 35 cm H 2 O Peak pressure 50 cm H 2 O, IPP 35 cm H 2 O End expiratory pressure is 20 cm End expiratory pressure is 20 cm pH 7.20, PaCO 2 60, PaO 2 215 pH 7.20, PaCO 2 60, PaO 2 215 Sinus tach 157 Sinus tach 157 BP 78/45 BP 78/45 No urine output No urine output Patient very agitated Patient very agitated What would you do? What would you do? RR 24 RR 24 I:E ratio = 1:1.5 I:E ratio = 1:1.5 Peak pressure 50 cm H 2 O, IPP 35 cm H 2 O Peak pressure 50 cm H 2 O, IPP 35 cm H 2 O End expiratory pressure is 20 cm End expiratory pressure is 20 cm pH 7.20, PaCO 2 60, PaO 2 215 pH 7.20, PaCO 2 60, PaO 2 215 Sinus tach 157 Sinus tach 157 BP 78/45 BP 78/45 No urine output No urine output Patient very agitated Patient very agitated What would you do? What would you do?

9. 9 CASE #3 37 year old healthy malpractice plaintiff attorney presents to ER with 24 hour history of generalized weakness. Last week he had a mild bout of gastroenteritis after eating under cooked chicken. He could walk with difficulty when he arrived at ER 8 hours ago. Now he needs help to reposition himself in bed and he coughs when he attempts to drink. 37 year old healthy malpractice plaintiff attorney presents to ER with 24 hour history of generalized weakness. Last week he had a mild bout of gastroenteritis after eating under cooked chicken. He could walk with difficulty when he arrived at ER 8 hours ago. Now he needs help to reposition himself in bed and he coughs when he attempts to drink.

10. 10 CASE #3 Exam normal except weakness Exam normal except weakness Chemistries and CBC normal Chemistries and CBC normal RA ABG pH 7.41 pCO2 41 pO2 84 RA ABG pH 7.41 pCO2 41 pO2 84 Vital Capacity 840cc (12cc/Kg) Vital Capacity 840cc (12cc/Kg) CXR at left CXR at left

11. 11 CASE #3 Where should this patient be cared for? ICU? Tele? Ward? Home? Where should this patient be cared for? ICU? Tele? Ward? Home? Should this patient be fed? Should this patient be fed? Should he be advised to call a lawyer? Should he be advised to call a lawyer? Would you put him on BiPAP? Would you put him on BiPAP? Anything else you would do? Anything else you would do?

12. Case # 4 A 25-year-old lady, Miss. Poor Compliance, is rushed into your Emergency Department. She is an asthmatic who on arrival is sitting forward in the tripod position, using her accessory muscles to breath. She is tachypneic, diaphoretic, agitated and unable to talk. During a nebulizer tx with albuterol she becomes dusky and poorly responsive. A 25-year-old lady, Miss. Poor Compliance, is rushed into your Emergency Department. She is an asthmatic who on arrival is sitting forward in the tripod position, using her accessory muscles to breath. She is tachypneic, diaphoretic, agitated and unable to talk. During a nebulizer tx with albuterol she becomes dusky and poorly responsive.Miss. Poor Compliancetripod positionMiss. Poor Compliancetripod position 12

13. Case # 4 13

14. Plan of care? Get ABG? Get ABG? Start BiPAP? Start BiPAP? Discuss patient’s “feelings” about being ill? Discuss patient’s “feelings” about being ill? Get advice from resident (oops, he is running a code) Get advice from resident (oops, he is running a code) Other? Other? 14

15. Acute Respiratory Failure Hypoxemic Hypoxemic – Room air PaO 2  50 torr Hypercapneic Hypercapneic – PaCO 2  50 torr Acute vs chronic Acute vs chronic Often Multifactorial Often Multifactorial Hypoxemic Hypoxemic – Room air PaO 2  50 torr Hypercapneic Hypercapneic – PaCO 2  50 torr Acute vs chronic Acute vs chronic Often Multifactorial Often Multifactorial ARF 15

16. 16 Pathophysiology of Hypoxemia Ventilation/perfusion mismatch Ventilation/perfusion mismatch Shunt effect (intracardiac or intrapulmonary) Shunt effect (intracardiac or intrapulmonary) Decreased diffusion of O 2 Decreased diffusion of O 2 Alveolar hypoventilation Alveolar hypoventilation FIO2 < 21% (eg. High altitude) FIO2 < 21% (eg. High altitude) Ventilation/perfusion mismatch Ventilation/perfusion mismatch Shunt effect (intracardiac or intrapulmonary) Shunt effect (intracardiac or intrapulmonary) Decreased diffusion of O 2 Decreased diffusion of O 2 Alveolar hypoventilation Alveolar hypoventilation FIO2 < 21% (eg. High altitude) FIO2 < 21% (eg. High altitude) ARF 16

17. 17 Pathophysiology of Hypercapnea Alveolar ventilation is the prime determinant of CO 2 exchange during mechanical ventilation Alveolar ventilation is the prime determinant of CO 2 exchange during mechanical ventilation V A ~ 1/pCO 2 V A ~ 1/pCO 2 V A =(V T -V D )f V A =(V T -V D )f Change in any variable affects pCO 2 Change in any variable affects pCO 2 Alveolar ventilation is the prime determinant of CO 2 exchange during mechanical ventilation Alveolar ventilation is the prime determinant of CO 2 exchange during mechanical ventilation V A ~ 1/pCO 2 V A ~ 1/pCO 2 V A =(V T -V D )f V A =(V T -V D )f Change in any variable affects pCO 2 Change in any variable affects pCO 2

18. 18 Causes of Hypercapnea Inability to sense elevated PaCO 2 Inability to sense elevated PaCO 2 Inability to signal respiratory muscles Inability to signal respiratory muscles Inability to effect a response from respiratory muscles Inability to effect a response from respiratory muscles Increased dead space Increased dead space

19. 19 Inability to effect adequate response from respiratory muscles Imbalance between demand for respiratory muscle work and the ability to supply that work Imbalance between demand for respiratory muscle work and the ability to supply that work Examples of increased demand: bronchospasm, fever, low lung compliance, pleural effusion Examples of increased demand: bronchospasm, fever, low lung compliance, pleural effusion Decreased supply: poor cardiac output, malnutrition, deconditioning Decreased supply: poor cardiac output, malnutrition, deconditioning

20. 20 Increased Dead Space (wasted ventilation) Hypovolemia Hypovolemia Low cardiac output Low cardiac output Pulmonary embolus Pulmonary embolus High airway pressures High airway pressures Short-term compensation by increasing tidal volume and/or respiratory rate Short-term compensation by increasing tidal volume and/or respiratory rate Hypovolemia Hypovolemia Low cardiac output Low cardiac output Pulmonary embolus Pulmonary embolus High airway pressures High airway pressures Short-term compensation by increasing tidal volume and/or respiratory rate Short-term compensation by increasing tidal volume and/or respiratory rate

21. 21 Manifestations of Respiratory Distress Altered mental status – especially anxiety!!! Altered mental status – especially anxiety!!! Anxiety is a result of respiratory distress, almost NEVER the cause. Anxiety is a result of respiratory distress, almost NEVER the cause. Increased work of breathing Increased work of breathing – Tachypnea, nasal flaring – Accessory muscle use, retractions, paradoxical breathing pattern, respiratory alternans Catecholamine release Catecholamine release – Tachycardia, diaphoresis, hypertension Abnormal ABG – not always!!! Abnormal ABG – not always!!! Neuromuscular failure is different from above Neuromuscular failure is different from above

22. Oxygen Supplementation low flow systems 1-10 LPM 100% O2 mixes with room air to determine FIO2 - definition FIO2 varies with patient’s breathing pattern – Rapid inspiration entrains more room air – Deep breaths entrain more room air – Rapid respiratory rate entrains more room air – Patients in more distress get lower FIO2 FIO2 is unknown since amount of entrainment is unknown Any humidity in gas comes from entrained air- wall O2 has 0% relative humidity Low flow devices Simple Nasal Cannulas Simple masks 22

23. High Flow O2 Devices > 20 - 60 lpm 23 Device provides 100% of gas to patient - definition Device provides 100% of gas to patient - definition No entrainment of room air if mask fits No entrainment of room air if mask fits FIO2 is known and exact FIO2 is known and exact Relative humidity depends on the device Relative humidity depends on the device High flow devices: High flow devices: – High flow nasal cannula – Venturi mask – Aerosol mask – heated or cool – Nonrebreather mask – some characteristics of both high and low

24. O2 Devices 24

25. Aerosol O2 devices 25

26. BiPAP or NPPV Contraindications Contraindications – Cardiac or respiratory arrest – Inability to cooperate, protect the airway, or clear secretions – Nonrespiratory organ failure, esp shock – Facial surgery, trauma, or deformity – Prolonged duration of mechanical ventilation anticipated – Recent esophageal anastomosis A need for emergent intubation is an absolute contraindication to NPPV A need for emergent intubation is an absolute contraindication to NPPV Set inspiratory pressure (IP) and exp pressure (PEEP) Set inspiratory pressure (IP) and exp pressure (PEEP) Mean pressure determines oxygenation Mean pressure determines oxygenation IP – PEEP determines ventilatory assist IP – PEEP determines ventilatory assist 26

27. 27 Endotracheal Intubation “….An opening must be attempted in the trunk of the trachea, into which a tube or cane should be put; You will then blow into this so that lung may rise again….And the heart becomes strong….” -Andreas Vesalius (1555) -Andreas Vesalius (1555)

28. 28 Indications for Endotracheal Intubation Airway protection (outside ICU?) Airway protection (outside ICU?) Relief of airway obstruction Relief of airway obstruction Respiratory failure or impending respiratory failure Respiratory failure or impending respiratory failure – Hypoxic or – Hypercapneic or both Need for hyperventilation -  ICP Need for hyperventilation -  ICP Unsustainable work of breathing Unsustainable work of breathing Facilitate suctioning/pulmonary toilet Facilitate suctioning/pulmonary toilet Shock !!!!!!!!!!! Shock !!!!!!!!!!!

29. 29 Decision to intubate Clinical decision-not based on ABG Clinical decision-not based on ABG Error on the side of patient safety Error on the side of patient safety What is the safest way to navigate illness? What is the safest way to navigate illness? Intubation is not an act of weakness Intubation is not an act of weakness Think ahead- if need to intubation is expected in next 24hr, intubate now Think ahead- if need to intubation is expected in next 24hr, intubate now Endotracheal tubes are not a disease and ventilators are not an addiction i.e. Intubation does not cause ventilator dependence Endotracheal tubes are not a disease and ventilators are not an addiction i.e. Intubation does not cause ventilator dependence

30. 30 Modes of Mechanical Ventilation Point of Reference: Spontaneous Ventilation

31. 31 Continuous Positive Airway Pressure (CPAP) No machine breaths delivered No machine breaths delivered Allows spontaneous breathing at elevated baseline pressure Allows spontaneous breathing at elevated baseline pressure Patient controls rate and tidal volume Patient controls rate and tidal volume No machine breaths delivered No machine breaths delivered Allows spontaneous breathing at elevated baseline pressure Allows spontaneous breathing at elevated baseline pressure Patient controls rate and tidal volume Patient controls rate and tidal volume

32. 32 Assist-Control Ventilation You set tidal volume and minimum rate You set tidal volume and minimum rate Additional breaths delivered with minimal inspiratory effort - pt sets actual rate Additional breaths delivered with minimal inspiratory effort - pt sets actual rate Advantages: reduced work of breathing; allows patient to modify minute ventilation Advantages: reduced work of breathing; allows patient to modify minute ventilation Most patients should start with this mode Most patients should start with this mode Rate 12, TV 8-10 cc/kg, FiO2 100% PEEP 5 Rate 12, TV 8-10 cc/kg, FiO2 100% PEEP 5 You set tidal volume and minimum rate You set tidal volume and minimum rate Additional breaths delivered with minimal inspiratory effort - pt sets actual rate Additional breaths delivered with minimal inspiratory effort - pt sets actual rate Advantages: reduced work of breathing; allows patient to modify minute ventilation Advantages: reduced work of breathing; allows patient to modify minute ventilation Most patients should start with this mode Most patients should start with this mode Rate 12, TV 8-10 cc/kg, FiO2 100% PEEP 5 Rate 12, TV 8-10 cc/kg, FiO2 100% PEEP 5

33. 33 Synchronized Intermittent Mandatory Ventilation (SIMV) Volume cycled breaths at a preset rate Volume cycled breaths at a preset rate Additional spontaneous breaths at tidal volume and rate determined by patient Additional spontaneous breaths at tidal volume and rate determined by patient Invented as weaning mode Invented as weaning mode Best weaning mode is sink or swim Best weaning mode is sink or swim Best use is to mitigate AutoPEEP Best use is to mitigate AutoPEEP Volume cycled breaths at a preset rate Volume cycled breaths at a preset rate Additional spontaneous breaths at tidal volume and rate determined by patient Additional spontaneous breaths at tidal volume and rate determined by patient Invented as weaning mode Invented as weaning mode Best weaning mode is sink or swim Best weaning mode is sink or swim Best use is to mitigate AutoPEEP Best use is to mitigate AutoPEEP

34. 34 Pressure-Support Ventilation Pressure assist during spontaneous inspiration with flow-cycled breath Pressure assist during spontaneous inspiration with flow-cycled breath Pressure assist at constant pressure continues until inspiratory effort decreases Pressure assist at constant pressure continues until inspiratory effort decreases Delivered tidal volume dependent on set pressure, inspiratory effort and resistance/compliance of lung/thorax Delivered tidal volume dependent on set pressure, inspiratory effort and resistance/compliance of lung/thorax Pressure assist during spontaneous inspiration with flow-cycled breath Pressure assist during spontaneous inspiration with flow-cycled breath Pressure assist at constant pressure continues until inspiratory effort decreases Pressure assist at constant pressure continues until inspiratory effort decreases Delivered tidal volume dependent on set pressure, inspiratory effort and resistance/compliance of lung/thorax Delivered tidal volume dependent on set pressure, inspiratory effort and resistance/compliance of lung/thorax

35. 35 Inspiratory Plateau Pressure Airway pressure measured at end of inspiration with no gas flow present Airway pressure measured at end of inspiration with no gas flow present Estimates alveolar pressure at end-inspiration Estimates alveolar pressure at end-inspiration IPP is best indicator of alveolar distension IPP is best indicator of alveolar distension PIP – IPP ~ airway resistance PIP – IPP ~ airway resistance Airway pressure measured at end of inspiration with no gas flow present Airway pressure measured at end of inspiration with no gas flow present Estimates alveolar pressure at end-inspiration Estimates alveolar pressure at end-inspiration IPP is best indicator of alveolar distension IPP is best indicator of alveolar distension PIP – IPP ~ airway resistance PIP – IPP ~ airway resistance Peak pressure Plateau pressure Inspiration Expiration

36. 36 Inspiratory Plateau Pressure High inspiratory plateau pressure – stiff lungs High inspiratory plateau pressure – stiff lungs – Barotrauma - no – Volutrauma – yes – pneumothorax, etc – Decreased cardiac output Methods to decrease IPP Methods to decrease IPP – Decrease tidal volume – ??? Decrease PEEP Goal IPP usually  30 cm H 2 O Goal IPP usually  30 cm H 2 O ARDS protocol: tidal volume 6 cc/kg IBW ARDS protocol: tidal volume 6 cc/kg IBW

37. 37 Auto-PEEP - common Occurs in setting of severe COPD or asthma Occurs in setting of severe COPD or asthma Very uncomfortable for patient - agitation Very uncomfortable for patient - agitation Can be measured on most ventilators Can be measured on most ventilators Increases peak, plateau, and mean airway pressures Increases peak, plateau, and mean airway pressures Hypotension – impaired venous return Hypotension – impaired venous return Suspect in setting of COPD or asthma pt who is agitated or hypotensive – this is common!!! Suspect in setting of COPD or asthma pt who is agitated or hypotensive – this is common!!! Occurs in setting of severe COPD or asthma Occurs in setting of severe COPD or asthma Very uncomfortable for patient - agitation Very uncomfortable for patient - agitation Can be measured on most ventilators Can be measured on most ventilators Increases peak, plateau, and mean airway pressures Increases peak, plateau, and mean airway pressures Hypotension – impaired venous return Hypotension – impaired venous return Suspect in setting of COPD or asthma pt who is agitated or hypotensive – this is common!!! Suspect in setting of COPD or asthma pt who is agitated or hypotensive – this is common!!!

38. 38 I:E Ratio during Mechanical Ventilation If expiratory time too short for full exhalation If expiratory time too short for full exhalation – Breath stacking – Auto-PEEP Reduce auto-PEEP by reducing inspiratory time/increasing expiratory time Reduce auto-PEEP by reducing inspiratory time/increasing expiratory time – Increase peak inspiratory flow rate – 100 lpm – Decrease respiratory rate (use IMV without PSV) – rate of 12 usually is good – Decrease tidal volume to 8 cc per kg IBW If expiratory time too short for full exhalation If expiratory time too short for full exhalation – Breath stacking – Auto-PEEP Reduce auto-PEEP by reducing inspiratory time/increasing expiratory time Reduce auto-PEEP by reducing inspiratory time/increasing expiratory time – Increase peak inspiratory flow rate – 100 lpm – Decrease respiratory rate (use IMV without PSV) – rate of 12 usually is good – Decrease tidal volume to 8 cc per kg IBW

39. 39 CASE # 1 J.T. is a 68-kg, 42-yr old female admitted after a drug overdose complicated by emesis and aspiration. Intubation and mechanical ventilation are initiated in the emergency department. J.T. is a 68-kg, 42-yr old female admitted after a drug overdose complicated by emesis and aspiration. Intubation and mechanical ventilation are initiated in the emergency department.

40. 40 CASE # 1 CASE # 1 Mechanical ventilation Mechanical ventilation – AC (volume) mode – Tidal volume 700 ml – 10 breaths/min – FIO 2 1.0 – always start at 100% – PEEP 5 cm H 2 O Mechanical ventilation Mechanical ventilation – AC (volume) mode – Tidal volume 700 ml – 10 breaths/min – FIO 2 1.0 – always start at 100% – PEEP 5 cm H 2 O

41. 41 CASE # 1 CASE # 1 Peak airway pressure 52 cm H 2 O Peak airway pressure 52 cm H 2 O Inspiratory plateau pressure (IPP) 48 cm H 2 O Inspiratory plateau pressure (IPP) 48 cm H 2 O pH 7.38, Pa CO 2 36 torr Pa O 2 57 torr pH 7.38, Pa CO 2 36 torr Pa O 2 57 torr Sinus tach at 166, BP 75/50 Sinus tach at 166, BP 75/50 Patient very “agitated” and “fighting vent” Patient very “agitated” and “fighting vent” What are the issues here? What are the issues here?

42. 42 CASE # 1 What is diagnosis? What is diagnosis? What are the consequences of What are the consequences of – FIO 2 100%? – TV 10cc/Kg? – High inspiratory plateau pressure? – Hypotension and tachycardia? – agitation and fighting vent What variables should be changed to improve PaO 2 ? BP? Protect lungs? What variables should be changed to improve PaO 2 ? BP? Protect lungs? What is diagnosis? What is diagnosis? What are the consequences of What are the consequences of – FIO 2 100%? – TV 10cc/Kg? – High inspiratory plateau pressure? – Hypotension and tachycardia? – agitation and fighting vent What variables should be changed to improve PaO 2 ? BP? Protect lungs? What variables should be changed to improve PaO 2 ? BP? Protect lungs?

43. 43ARDS Decreased lung compliance results in high airway pressures Decreased lung compliance results in high airway pressures Tidal volume goal 6cc/Kg Tidal volume goal 6cc/Kg Maintain IPP  30 cm H 2 O Maintain IPP  30 cm H 2 O PEEP to improve oxygenation PEEP to improve oxygenation Aim for FIO2 50% - O2 toxic at > 50% Aim for FIO2 50% - O2 toxic at > 50% Patients often need volume loading, sometimes guided by Swan Patients often need volume loading, sometimes guided by Swan Sedation (sometimes paralytic) needed Sedation (sometimes paralytic) needed

44. 44 CASE #2 L.W. is a 62-yr-old, 52-kg female with severe emphysema. For 2 days she has had progressive dyspnea and was found unresponsive. ABG on 5 liters NC pH 7.07 pCO2 87 pO2 42. L.W. is a 62-yr-old, 52-kg female with severe emphysema. For 2 days she has had progressive dyspnea and was found unresponsive. ABG on 5 liters NC pH 7.07 pCO2 87 pO2 42. She required intubation and initiation of mechanical ventilation. She required intubation and initiation of mechanical ventilation. L.W. is a 62-yr-old, 52-kg female with severe emphysema. For 2 days she has had progressive dyspnea and was found unresponsive. ABG on 5 liters NC pH 7.07 pCO2 87 pO2 42. L.W. is a 62-yr-old, 52-kg female with severe emphysema. For 2 days she has had progressive dyspnea and was found unresponsive. ABG on 5 liters NC pH 7.07 pCO2 87 pO2 42. She required intubation and initiation of mechanical ventilation. She required intubation and initiation of mechanical ventilation.

45. 45 CASE #2 ICU ventilator settings AC, rate 12 breaths/min AC, rate 12 breaths/min FIO 2 1.0 FIO 2 1.0 Tidal volume 600 ml Tidal volume 600 ml Peak flow 50 l/sec Peak flow 50 l/sec PEEP 5 cm H 2 O PEEP 5 cm H 2 O ICU ventilator settings AC, rate 12 breaths/min AC, rate 12 breaths/min FIO 2 1.0 FIO 2 1.0 Tidal volume 600 ml Tidal volume 600 ml Peak flow 50 l/sec Peak flow 50 l/sec PEEP 5 cm H 2 O PEEP 5 cm H 2 O

46. 46 CASE #2 RR 24 RR 24 I:E ratio = 1:1.5 I:E ratio = 1:1.5 Peak pressure 50 cm H 2 O, IPP 35 cm H 2 O Peak pressure 50 cm H 2 O, IPP 35 cm H 2 O End Expiratory Alveolar Pressure 20 cm H 2 O End Expiratory Alveolar Pressure 20 cm H 2 O pH 7.28, PaCO 2 60 torr, PaO 2 215 torr pH 7.28, PaCO 2 60 torr, PaO 2 215 torr Sinus tach 157 Sinus tach 157 BP 78/45 BP 78/45 No urine output No urine output Patient very agitated Patient very agitated RR 24 RR 24 I:E ratio = 1:1.5 I:E ratio = 1:1.5 Peak pressure 50 cm H 2 O, IPP 35 cm H 2 O Peak pressure 50 cm H 2 O, IPP 35 cm H 2 O End Expiratory Alveolar Pressure 20 cm H 2 O End Expiratory Alveolar Pressure 20 cm H 2 O pH 7.28, PaCO 2 60 torr, PaO 2 215 torr pH 7.28, PaCO 2 60 torr, PaO 2 215 torr Sinus tach 157 Sinus tach 157 BP 78/45 BP 78/45 No urine output No urine output Patient very agitated Patient very agitated

47. 47 CASE #2 What is the diagnosis? What is the diagnosis? What variable(s) should be changed to improve the ABG ? BP? UO? Agitation? What variable(s) should be changed to improve the ABG ? BP? UO? Agitation? What are the consequences of What are the consequences of –change in peak flow rate ? –change in respiratory rate ? –change in ventilator mode? –bronchodilators ? –High peak pressure? What is the diagnosis? What is the diagnosis? What variable(s) should be changed to improve the ABG ? BP? UO? Agitation? What variable(s) should be changed to improve the ABG ? BP? UO? Agitation? What are the consequences of What are the consequences of –change in peak flow rate ? –change in respiratory rate ? –change in ventilator mode? –bronchodilators ? –High peak pressure?

48. 48 Analysis  Patient L.W. Hypercapnea acceptable if pH OK Hypercapnea acceptable if pH OK High peak airway pressure can be OK High peak airway pressure can be OK Wide peak-plateau pressure difference indicates obstructive disease Wide peak-plateau pressure difference indicates obstructive disease Be alert for auto-PEEP Be alert for auto-PEEP Hypotension and tachycardia suggest auto-PEEP and or inadequate preload Hypotension and tachycardia suggest auto-PEEP and or inadequate preload Hypercapnea acceptable if pH OK Hypercapnea acceptable if pH OK High peak airway pressure can be OK High peak airway pressure can be OK Wide peak-plateau pressure difference indicates obstructive disease Wide peak-plateau pressure difference indicates obstructive disease Be alert for auto-PEEP Be alert for auto-PEEP Hypotension and tachycardia suggest auto-PEEP and or inadequate preload Hypotension and tachycardia suggest auto-PEEP and or inadequate preload

49. 49 Obstructive Airway Disease Obstructive diseases require adequate expiratory time Obstructive diseases require adequate expiratory time PaCO 2 should be kept at patient’s baseline level PaCO 2 should be kept at patient’s baseline level Obstructive diseases require adequate expiratory time Obstructive diseases require adequate expiratory time PaCO 2 should be kept at patient’s baseline level PaCO 2 should be kept at patient’s baseline level

50. 50 Neuromuscular Disease Case 37 year old healthy lawyer admitted from ER with 24 hour history of generalized weakness. Last week he had a mild bout of gastroenteritis. He could walk with difficulty when he arrived at ER 12 hours ago. Now he needs help to reposition himself in bed and he coughs when he attempts to drink. 37 year old healthy lawyer admitted from ER with 24 hour history of generalized weakness. Last week he had a mild bout of gastroenteritis. He could walk with difficulty when he arrived at ER 12 hours ago. Now he needs help to reposition himself in bed and he coughs when he attempts to drink.

51. 51 Neuromuscular Disease Case Exam normal except weakness Exam normal except weakness Chemistries and CBC normal Chemistries and CBC normal RA ABG pH 7.41 pCO2 41 pO2 84 RA ABG pH 7.41 pCO2 41 pO2 84 Vital Capacity 840cc (12cc/Kg) Vital Capacity 840cc (12cc/Kg)

52. 52 Neuromuscular Disease Case Where should this patient be cared for? ICU? Tele? Ward? Home? Where should this patient be cared for? ICU? Tele? Ward? Home? Should this patient be fed? Should this patient be fed? Should this patient be intubated? Should this patient be intubated?

53. 53 Neuromuscular Disease Patients do not appear to struggle Patients do not appear to struggle ABG does not tell you when to intubate ABG does not tell you when to intubate Delay may result in aspiration and arrest Delay may result in aspiration and arrest Follow vital capacity closely in ICU Follow vital capacity closely in ICU Intubate when VC approaches 15cc/Kg Intubate when VC approaches 15cc/Kg

54. Case # 4 54

55. Plan of care? Get ABG? Get ABG? Start BiPAP? Start BiPAP? Discuss patient’s “feelings” about being ill? Discuss patient’s “feelings” about being ill? Check her health insurance Check her health insurance Get advice from resident (oops, he is running a code) Get advice from resident (oops, he is running a code) Other? Other? 55