Tissue is the Issue perfusione PEEP CPAP FiO2 HFNC PSV HFNC DO 2 = CO [(Hb x 1.34) SaO 2 + 0.003 PaO 2 ]
O2 HFNC PEEP CPAP PSV ARF
ACPE
HIGH FLOW NASAL CANNULA High and Exact FiO2, High Flow heating and humidification, well tolerated Remove CO2 from high respiratory tract Nasopharyngeal dead space washout has been proposed to reduce CO2 rebreathing, thus providing a fresh reservoir of oxygen from which to breathe PEEP? pharyngeal pressures of 2 8 cm H2O contributing to lung recruitment and upper airway splinting
FiO2 32-100% Flow 10-60L/min FiO2 21-60% Flow 15-45L/min
O2 20L/min Flow 50L/min
acute and chronic RF Settings: HFNC Pediatrics SDB COPD Hypoxaemic ARF postextubation preintubation oxygenation acute heart failure DNI
HFNC was initiated as a front line therapy in place of other oxygen therapy modalities, and used based on clinician discretion. 75% of HFNC interventions involved patients with hypoxemia and 25% of them involved elevated arterial carbon dioxide levels. Respondents indicated excellent respiratory responses as well as high ease of use and patient tolerance. Disposition decisions were to admit 41% of cases to the ICU, 54% to the medical floor and 5% to discharge. HFNC may be useful in the ED to rapidly stabilize patients in significant respiratory distress with an easily tolerated respiratory support modality. Clinical use guidelines were established that were effective and acceptable to clinical staff. The use of the therapy may have utility in reducing ICU admissions associated with the use of NIPPV as a primary respiratory modality.
In patients with acute hypoxemic respiratory failure, HFNC oxygen therapy was associated with a reduction in the proportion requiring endotracheal intubation and a decreased respiratory rate compared with conventional oxygen therapy In the comparison of HFNC oxygen therapy and noninvasive ventilation, no differences were observed in the intubation rate, Paco2 level or arterial ph, but the respiratory rate was significantly lower in the HFNC group. ICU mortality did not differ between groups.
PEEP CPAP shifts the lungs to a more compliant portion of P/V curve
PEEP 0 Shunt 50% PEEP keep the lung open PEEP 15 Shunt 15% FRC PEEP 10 Shunt 25%
EFFETTI EMODINAMICI EFFETTI VENTILATORI PEEP Migliorare gli scambi gassosi (reclutamento alveolare) Migliorare la meccanica polmonare (CFR) Aumento PIT Ritorno Venoso Resistenze Vascolari Polmonari Volumi Cardiaci P transmurale Ventricolare Pre/Post carico ventricolare Output Cardiaco
PEEP: Effetti Emodinamici PEEP = PIT riempimento ventricolare in diastole PRECARICO Facilita lo svuotamento ventricolare in sistole POST CARICO L effetto sulla Gittata Cardiaca ( o ) deriva dalla combinazione dei 2 effetti, dal prevalere di uno rispetto all altro, e dipende dal contesto clinico
ARDS Polmonite Shunt - V/Q - Ipox EPAc PEEP = PIT Precarico VDx-Sn Postcarico VDx-Sn Ritorno Venoso Volumi Cardiaci Resistenze Polmonari EFFETTO PREVALENTE MECCANISMI Postcarico VSn Precarico VDx P Transmurale Vsn Resistenze Polmonari Ritorno Venoso CO liquidi/amine + VM + CO diuretici/nitrati
Best PEEP? Hemodynamic Effects Respiratory Effects
PEEP in ACPE with preserved LVEF
The role of continuous positive airway pressure in acute cardiogenic edema with preserved left ventricular systolic function A.Bellone et al Compare the effect of continuous positive airway pressure (CPAP) in patients with acute cardiogenic pulmonary edema (ACPE) with preserved or impaired left ventricular systolic function with regard to resolution time Resolution time is not significantly different in patients with ACPE with preserved or impaired systolic function submitted to CPAP 2009 Oct;27(8):986-91
In restrictive AHRF lung volume is reduced, lung is poorly ventilated. PEEP may assist in lung recruitment, improve compliance and correct Hypoxaemia... Increasing PEEP for a given inspiratory pressure increases Vt, reduces pco2. In obstructive disease with flow limitation (COPD), PEEP improves expiratory airflow (reduces obstruction), limits dynamic hyperinflation improves compliance and may improve tidal volume ( improves alveolar ventilation). In NIV epeep improves triggering and patient comfort, reduces WOB (vs ipeep)
From Appendini L. et al. Am J Respir Crit Care Med 1996; 154:1301-1309 PTPdi= extimate of diaphragm O2 consumption 41% Pres Pel,L Pel,w PEEPi 37% PEEPi 15% 7%
Pressure Support Vt V E Obstructive Pts Raw Restrictive Pts Compliance
At high levels of inspiratory pressure-assist, NIV consistently increased dynamic lung compliance and tidal volume, improved arterial blood gases NIV reduces WOB and inspiratory effort in direct proportion to the level of inspiratory pressure-assist, and also by the ability of applied positive end-expiratory pressure (PEEP) to counter intrinsic PEEP. This occurs in in patients with diverse etiologies and severity of pulmonary disease. Consequently reduces dyspnea.
High PS and Rise Time Pts compliance Air Leaks Effort
L. Appendini et al. Am J Respir Crit care Med 1994; 149: 1069-1076
PSV PEEP
Airway recruitment in Pts with Flow Limitation (CV)