11 Italian perspectives: Helmet Courtesy of Dr Massimo Antonelli (Rome)  Latex-free transparent PVC  Secured by 2 arm = pit braces (A) at two hooks (B) of the metallic ring (C) joining helmet with a soft collar (D)  A seal connection (E) allows the passage of NGT  Latex-free transparent PVC  Secured by 2 arm = pit braces (A) at two hooks (B) of the metallic ring (C) joining helmet with a soft collar (D)  A seal connection (E) allows the passage of NGT A B C D E

22 HelmetHelmet InP = Inspiratory port; ExP = expiratory port; SC = sealed connector; BR= armpit braces

33 HypoxemicHypercapnic IPPV Augment ventilation CPAP Recruit lung units Decrease afterload Offset PEEPi Modes of Ventilation

44  Recruits lung units improved V/Q matching > rapid correction of PaO 2 & PaCO 2 1 improved V/Q matching > rapid correction of PaO 2 & PaCO 2 1 increased functional residual capacity increased functional residual capacity decreased respiratory rate and WOB2 decreased respiratory rate and WOB2  Reduces airway resistance 2  Improves hemodynamics in pulmonary edema decreases venous return decreases venous return decreases afterload and increases cardiac index (in 50%) 1-4 decreases afterload and increases cardiac index (in 50%) 1-4 decreases heart rate 1-3 decreases heart rate 1-3  Average requirement: 10cmH 2 O  Recruits lung units improved V/Q matching > rapid correction of PaO 2 & PaCO 2 1 improved V/Q matching > rapid correction of PaO 2 & PaCO 2 1 increased functional residual capacity increased functional residual capacity decreased respiratory rate and WOB2 decreased respiratory rate and WOB2  Reduces airway resistance 2  Improves hemodynamics in pulmonary edema decreases venous return decreases venous return decreases afterload and increases cardiac index (in 50%) 1-4 decreases afterload and increases cardiac index (in 50%) 1-4 decreases heart rate 1-3 decreases heart rate 1-3  Average requirement: 10cmH 2 O Mask CPAP in Hypoxemic Failure 1. Bersten NEJOM Rasanen AJC Lenique AJRCCM Bradley ARRD Bersten NEJOM Rasanen AJC Lenique AJRCCM Bradley ARRD 1992

55 CPAP in Congestive Heart Failure  CPAP in CHF Reduces systolic LVP tm by changing P es from negative to positive Reduces systolic LVP tm by changing P es from negative to positive  CPAP in CHF Reduces systolic LVP tm by changing P es from negative to positive Reduces systolic LVP tm by changing P es from negative to positive Naughton et al Circulation 1995; 91:1725  LVP tm during systole LVP tm = ventricular systolic pressure - extracardiac pressure (i.e., pericardial pr.) LVP tm = ventricular systolic pressure - extracardiac pressure (i.e., pericardial pr.) Changes in P es = changes in pericardial pr. Changes in P es = changes in pericardial pr. During inspiration > large negative intrathoracic pressure swings increase LVP tm and afterload During inspiration > large negative intrathoracic pressure swings increase LVP tm and afterload  LVP tm during systole LVP tm = ventricular systolic pressure - extracardiac pressure (i.e., pericardial pr.) LVP tm = ventricular systolic pressure - extracardiac pressure (i.e., pericardial pr.) Changes in P es = changes in pericardial pr. Changes in P es = changes in pericardial pr. During inspiration > large negative intrathoracic pressure swings increase LVP tm and afterload During inspiration > large negative intrathoracic pressure swings increase LVP tm and afterload   Pes Negative  Pes Positive Lung inflation  parasympathetic tone   sympathetic outflow   HR Lung inflation  parasympathetic tone   sympathetic outflow   HR Reduction in O 2 consumption Reduction in O 2 consumption – Myocardial: systolic LVP tm x HR – Pulmonary: P es x RR Lung inflation  parasympathetic tone   sympathetic outflow   HR Lung inflation  parasympathetic tone   sympathetic outflow   HR Reduction in O 2 consumption Reduction in O 2 consumption – Myocardial: systolic LVP tm x HR – Pulmonary: P es x RR

66  Expiratory flow limitation  Dynamic hyperinflation  Respiratory muscle fatigue  Respiratory acidosis  Expiratory flow limitation  Dynamic hyperinflation  Respiratory muscle fatigue  Respiratory acidosis COPD: Pathophysiology of ARF

77 COPD: Dynamic Hyperinflation  Auto PEEP = inspiratory threshold load  Flattened diaphragm = reduced efficiency and endurance shortening of the sarcomere length and decreased maximal force shortening of the sarcomere length and decreased maximal force reduced zone of apposition with the chest wall (expansion on insp.) reduced zone of apposition with the chest wall (expansion on insp.) reduced blood supply reduced blood supply

88  COPD patient stable average PEEPi 2.4 ± 1.6 cm H 2 O 1 average PEEPi 2.4 ± 1.6 cm H 2 O 1  COPD patient with acute exacerbation average PEEPi 6.5 ± 2.5 cm H2O2,3 average PEEPi 6.5 ± 2.5 cm H2O2,3 PEEPi = 43±5% total work by respiratory system 4 PEEPi = 43±5% total work by respiratory system 4  Increased O 2 cost correlates with diaphr. flattening on CXR 5  COPD patient stable average PEEPi 2.4 ± 1.6 cm H 2 O 1 average PEEPi 2.4 ± 1.6 cm H 2 O 1  COPD patient with acute exacerbation average PEEPi 6.5 ± 2.5 cm H2O2,3 average PEEPi 6.5 ± 2.5 cm H2O2,3 PEEPi = 43±5% total work by respiratory system 4 PEEPi = 43±5% total work by respiratory system 4  Increased O 2 cost correlates with diaphr. flattening on CXR 5 COPD: Intrinsic PEEP 1. Dal Vecchio et al Eur Respir J 1990; 3:743. Brocard et al NEJOM 1990; 323: Appendini et al AJRCCM 1994; 149: Jubran et al AJRCCM 1995; 152: Pitcher et al J Appl Physiol 1993; 74: Dal Vecchio et al Eur Respir J 1990; 3:743. Brocard et al NEJOM 1990; 323: Appendini et al AJRCCM 1994; 149: Jubran et al AJRCCM 1995; 152: Pitcher et al J Appl Physiol 1993; 74: 2750

99 Etiology of ARFPharmacological Treatment Etiology of ARF Pharmacological Treatment precipitating condition  bronchodilator, anti-inflammatory antibiotics, etc. Physiology of ARF Positive pressure expiratory flow limitation causes bronchodilation expiratory flow limitation  causes bronchodilation dynamic hyperinflation offsets intrinsic PEEP (  load) dynamic hyperinflation  offsets intrinsic PEEP (  load) respiratory muscle fatigue reduces diaphragmatic activity respiratory muscle fatigue  reduces diaphragmatic activity respiratory acidosis increases VE (  Vt,  RR) respiratory acidosis  increases VE (  Vt,  RR) Etiology of ARFPharmacological Treatment Etiology of ARF Pharmacological Treatment precipitating condition  bronchodilator, anti-inflammatory antibiotics, etc. Physiology of ARF Positive pressure expiratory flow limitation causes bronchodilation expiratory flow limitation  causes bronchodilation dynamic hyperinflation offsets intrinsic PEEP (  load) dynamic hyperinflation  offsets intrinsic PEEP (  load) respiratory muscle fatigue reduces diaphragmatic activity respiratory muscle fatigue  reduces diaphragmatic activity respiratory acidosis increases VE (  Vt,  RR) respiratory acidosis  increases VE (  Vt,  RR) COPD: Management of ARF

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1111 HypoxemicHypercapnic IPPV Augment ventilation CPAP Recruit lung units Decrease afterload Offset PEEPi Modes of Ventilation

1212 COPD: Inspiratory Effort and PEEPi  isometric contraction to counterbalance PEEPi (inspiratory threshold load) atmospheric pressure Auto PEEP 8 cm H 2 O external PEEP 6 cm H 2 O external PEEP 6 cm H 2 O Auto PEEP 8 cm H 2 O Inspiratory Pressure 4 cm H 2 O Inspiratory Pressure 4 cm H 2 O Appendini et al. AJRCCM 1994; 149: 1069 in COPD with ARF the inspiratory effort to lower alveolar pressure below ambient pressure is divided into two components: Inspiratory Pressure 10 cm H 2 O Inspiratory Pressure 10 cm H 2 O  isotonic contraction to generate inspiratory flow and tidal volume IT

1313  Offsets PEEPi 1  acute COPD exacerbation: average PEEPi cmH 2 O 1  acute COPD exacerbation: average PEEPi cmH 2 O 1  apply PEEP at 80-90% of PEEPi to avoid overdistention 1  apply PEEP at 80-90% of PEEPi to avoid overdistention 1  Reduces transdiaphragmatic pressure 2  May improve Vt, VE, or PaCO 2 4  no response within 30 min in 4 studies 1,2,5,6  no response within 30 min in 4 studies 1,2,5,6  delayed response (> 4 h) in clinical studies 4  delayed response (> 4 h) in clinical studies 4  Average CPAP requirement: 5 cmH 2 0  Offsets PEEPi 1  acute COPD exacerbation: average PEEPi cmH 2 O 1  acute COPD exacerbation: average PEEPi cmH 2 O 1  apply PEEP at 80-90% of PEEPi to avoid overdistention 1  apply PEEP at 80-90% of PEEPi to avoid overdistention 1  Reduces transdiaphragmatic pressure 2  May improve Vt, VE, or PaCO 2 4  no response within 30 min in 4 studies 1,2,5,6  no response within 30 min in 4 studies 1,2,5,6  delayed response (> 4 h) in clinical studies 4  delayed response (> 4 h) in clinical studies 4  Average CPAP requirement: 5 cmH 2 0 COPD: Mask CPAP in ARF 1. Appendeni AJRCCM Martin ARRD Shivaram Resp Gottfried Chest De Lucas Chest Elliot BMJ Appendeni AJRCCM Martin ARRD Shivaram Resp Gottfried Chest De Lucas Chest Elliot BMJ 1994

1414 BMJ 2003; 326:185.

1515  In COPD, the ventilatory response to raised PaCO 2 is decreased especially during sleep.  NPPV lowers nocturnal PaCO 2 and resets the respiratory control centre to become more responsive to increased PaCO 2 by increasing the neural output to the diaphragm and other respiratory muscles.  These patients are then able to maintain a more normal PaCO 2 throughout the daylight hours without the need for mechanical ventilation.  In COPD, the ventilatory response to raised PaCO 2 is decreased especially during sleep.  NPPV lowers nocturnal PaCO 2 and resets the respiratory control centre to become more responsive to increased PaCO 2 by increasing the neural output to the diaphragm and other respiratory muscles.  These patients are then able to maintain a more normal PaCO 2 throughout the daylight hours without the need for mechanical ventilation.

1616 HypoxemicHypercapnic IPPV Augment ventilation CPAP Recruit lung units Decrease afterload Offset PEEPi Modes of Ventilation

1717  Synchrony between patient effort and delivered assistance  NPPV with PSV is superior to (ABG and RMR) spontaneous breathing 1-5 spontaneous breathing 1-5 CPAP CPAP  Comparison to volume-cycled ventilation (COPD) 6 equally effective in improving gas exchange equally effective in improving gas exchange better tolerated and lower incidence of complications better tolerated and lower incidence of complications lower mask air leakage (lower peak mask pressure) lower mask air leakage (lower peak mask pressure)  Synchrony between patient effort and delivered assistance  NPPV with PSV is superior to (ABG and RMR) spontaneous breathing 1-5 spontaneous breathing 1-5 CPAP CPAP  Comparison to volume-cycled ventilation (COPD) 6 equally effective in improving gas exchange equally effective in improving gas exchange better tolerated and lower incidence of complications better tolerated and lower incidence of complications lower mask air leakage (lower peak mask pressure) lower mask air leakage (lower peak mask pressure) Mask Inspiratory Pressure Support 1. Appendeni AJRCCM Broachard NEJOM Ambrosino Chest Belman Chest Carrey Chest Vitacca ICM Appendeni AJRCCM Broachard NEJOM Ambrosino Chest Belman Chest Carrey Chest Vitacca ICM 1993

1818 Effect of Mask Pressure COPD patient with acute exacerbation PSV 15 cmH 2 O Positive Pes swings Additional reduction PSV 12 cmH 2 O synchrony Reduction Pes swings spontaneousbreathing Asynchrony PAM Carrey et al. Chest 1990; 97:150

1919 Timing to Suppression of EMG Activity Carrey et al. Chest 1990; 97: 150. Initiation of NPPV Within 5 breathes

2020 Mask CPAP and PSV in COPD Critical Pdi max Seven COPD patients with acute exacerbation Nasal mask - 15 min. recordings Seven COPD patients with acute exacerbation Nasal mask - 15 min. recordings 5 cmH 2 O 10 cmH 2 O Appendini AJRCCM 1994; 149: 1069

2121 Data obtained from: Ambrosino Chest 1992; Apprendini AJRCCM 1994; Brochard NEJOM 1990; Carrey Chest 1990; De Lucas Chest 1993; Elliot Anaesthesia 1994 Data obtained from: Ambrosino Chest 1992; Apprendini AJRCCM 1994; Brochard NEJOM 1990; Carrey Chest 1990; De Lucas Chest 1993; Elliot Anaesthesia 1994 Effects of CPAP and IPPV Hypercapnic vs Hypoxemic ARF Effects of CPAP and IPPV Hypercapnic vs Hypoxemic ARF