How to set ASV® correctly for a (COVID-19) ARDS patient

Article

Author: Munir Karjaghli

Date of first publication: 23.03.2020

Downloads

This article describes step-by-step how to set the ventilator when using the Adaptive Support Ventilation (ASV) mode on ARDS patients.

How to set ASV® correctly for a (COVID-19) ARDS patient

How does ASV work?

ASV targets the optimal respiratory rate for the low compliance of an ARDS patient and already targets low tidal volumes as recommended in the ARDS guidelines (NIH NHLBI ARDS Clinical Network Mechanical Ventilation Protocol Summary 2008-07.1).

For any given minute volume, ASV determines the optimal respiratory rate and tidal volume associated with the minimal work of breathing and minimal driving pressure. It applies lung-protective ventilation with low tidal volumes (VT), and limited Pplateau and driving pressure in passive ICU patients with different lung conditions. In ARDS patients, ASV applies individualized lung-protective ventilation (Arnal JM, Saoli MS, Novotni D, Garnero A. Driving pressure automatically selected by INTELLiVENT-ASV in ICU patients. Intensive Care Med Exp 2016; 4 (Suppl 1):A602.2, Arnal JM, Saoli M, Garnero A. Airway and transpulmonary driving pressures and mechanical powers selected by INTELLiVENT-ASV in passive, mechanically ventilated ICU patients. Heart Lung. 2020;49(4):427-434. doi:10.1016/j.hrtlng.2019.11.0013).

Settings window on ventilator showing settings for patient height and gender — Figure 1: Enter patient height and select gender

Patient information and initial settings

Step 1: Determine patient height and select gender

See Figure 1 above.

Step 2: Initial settings

%MinVol setting of 120% (this corresponds to 120 ml/kg IBW/min)
PEEP setting of 8 cmH2O
Oxygen 100% adjust according to your blood gas examinations

Be aware that tidal volumes delivered by ASV can be limited by means of the pressure limitation (Pasvlimit) setting. Adjust the Pasvlimit according your Pplateau measurement results if needed. Normally a Pasvlimit ≤30 cmH2O is sufficient; in severe cases with low chest wall compliance or high airway resistance, a higher Pasvlimit up to 35 cmH2O might be needed. Verify your PEEP and Pasvlimit settings according to transpulmonary pressure measurement. Keep the driving pressure below 14 cmH20 (Amato MB, Meade MO, Slutsky AS, et al. Driving pressure and survival in the acute respiratory distress syndrome. N Engl J Med. 2015;372(8):747-755. doi:10.1056/NEJMsa14106394) and the transpulmonary driving pressure below 10 cmH20.

Adjustments

Step 3: Adjust %MinVol and Pasvlimit

Increase or decrease the %MinVol to reach the target PaCO2 in passive patients. In spontaneously breathing patients, increase or decrease the %MinVol to change the level of pressure support.

Assess recruitability

Step 4: Consider an early recruitability assessment

An RCT (Writing Group for the Alveolar Recruitment for Acute Respiratory Distress Syndrome Trial (ART) Investigators, Cavalcanti AB, Suzumura ÉA, et al. Effect of Lung Recruitment and Titrated Positive End-Expiratory Pressure (PEEP) vs Low PEEP on Mortality in Patients With Acute Respiratory Distress Syndrome: A Randomized Clinical Trial. JAMA. 2017;318(14):1335-1345. doi:10.1001/jama.2017.141715) investigating high PEEP and prolonged high pressure RMs showed harm to the lung, suggesting that the protocol used in this RCT should be avoided. In those trials however, patients were not screened for recruitability and they were exposed to high pressures over a long time. We recommend using the P/V Tool Pro for an early assessment of recruitability; if a patient is a responder, recruitment should be carried out promptly with the P/V Tool Pro.

Full citations below: (NIH NHLBI ARDS Clinical Network Mechanical Ventilation Protocol Summary 2008-07.1, Arnal JM, Saoli MS, Novotni D, Garnero A. Driving pressure automatically selected by INTELLiVENT-ASV in ICU patients. Intensive Care Med Exp 2016; 4 (Suppl 1):A602.2, Arnal JM, Saoli M, Garnero A. Airway and transpulmonary driving pressures and mechanical powers selected by INTELLiVENT-ASV in passive, mechanically ventilated ICU patients. Heart Lung. 2020;49(4):427-434. doi:10.1016/j.hrtlng.2019.11.0013, Amato MB, Meade MO, Slutsky AS, et al. Driving pressure and survival in the acute respiratory distress syndrome. N Engl J Med. 2015;372(8):747-755. doi:10.1056/NEJMsa14106394, Writing Group for the Alveolar Recruitment for Acute Respiratory Distress Syndrome Trial (ART) Investigators, Cavalcanti AB, Suzumura ÉA, et al. Effect of Lung Recruitment and Titrated Positive End-Expiratory Pressure (PEEP) vs Low PEEP on Mortality in Patients With Acute Respiratory Distress Syndrome: A Randomized Clinical Trial. JAMA. 2017;318(14):1335-1345. doi:10.1001/jama.2017.141715)

For additional information on COVID-19:

WHO guidelines: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/technical-guidance

ESICM information: https://www.esicm.org/resources/coronavirus-public-health-emergency/

Current evidence about COVID-19: https://jamanetwork.com/journals/jama/pages/coronavirus-alert

Centers for Disease Control and Prevention, CDC: https://www.cdc.gov/coronavirus/2019-ncov/hcp/clinical-guidance-management-patients.html

Footnotes

References

1. NIH NHLBI ARDS Clinical Network Mechanical Ventilation Protocol Summary 2008-07.
2. Arnal JM, Saoli MS, Novotni D, Garnero A. Driving pressure automatically selected by INTELLiVENT-ASV in ICU patients. Intensive Care Med Exp 2016; 4 (Suppl 1):A602.
3. Arnal JM, Saoli M, Garnero A. Airway and transpulmonary driving pressures and mechanical powers selected by INTELLiVENT-ASV in passive, mechanically ventilated ICU patients. Heart Lung. 2020;49(4):427-434. doi:10.1016/j.hrtlng.2019.11.001
4. Amato MB, Meade MO, Slutsky AS, et al. Driving pressure and survival in the acute respiratory distress syndrome. N Engl J Med. 2015;372(8):747-755. doi:10.1056/NEJMsa1410639
5. Writing Group for the Alveolar Recruitment for Acute Respiratory Distress Syndrome Trial (ART) Investigators, Cavalcanti AB, Suzumura ÉA, et al. Effect of Lung Recruitment and Titrated Positive End-Expiratory Pressure (PEEP) vs Low PEEP on Mortality in Patients With Acute Respiratory Distress Syndrome: A Randomized Clinical Trial. JAMA. 2017;318(14):1335-1345. doi:10.1001/jama.2017.14171
5. Writing Group for the Alveolar Recruitment for Acute Respiratory Distress Syndrome Trial (ART) Investigators, Cavalcanti AB, Suzumura ÉA, et al. Effect of Lung Recruitment and Titrated Positive End-Expiratory Pressure (PEEP) vs Low PEEP on Mortality in Patients With Acute Respiratory Distress Syndrome: A Randomized Clinical Trial. JAMA. 2017;318(14):1335-1345. doi:10.1001/jama.2017.14171

NIH NHLBI ARDS Clinical Network Mechanical Ventilation Protocol Summary

NIH NHLBI ARDS Clinical Network Mechanical Ventilation Protocol Summary 2008-07.

Driving pressure automatically selected by INTELLiVENT-ASV in ICU patients

Arnal JM, Saoli MS, Novotni D, Garnero A. Driving pressure automatically selected by INTELLiVENT-ASV in ICU patients. Intensive Care Med Exp 2016; 4 (Suppl 1):A602.

Airway and transpulmonary driving pressures and mechanical powers selected by INTELLiVENT-ASV in passive, mechanically ventilated ICU patients.

Arnal JM, Saoli M, Garnero A. Airway and transpulmonary driving pressures and mechanical powers selected by INTELLiVENT-ASV in passive, mechanically ventilated ICU patients. Heart Lung. 2020;49(4):427-434. doi:10.1016/j.hrtlng.2019.11.001

Link to article

BACKGROUND

Driving pressure (ΔP) and mechanical power (MP) are predictors of the risk of ventilation- induced lung injuries (VILI) in mechanically ventilated patients. INTELLiVENT-ASV® is a closed-loop ventilation mode that automatically adjusts respiratory rate and tidal volume, according to the patient's respiratory mechanics.

OBJECTIVES

This prospective observational study investigated ΔP and MP (and also transpulmonary ΔP (ΔPL) and MP (MPL) for a subgroup of patients) delivered by INTELLiVENT-ASV.

METHODS

Adult patients admitted to the ICU were included if they were sedated and met the criteria for a single lung condition (normal lungs, COPD, or ARDS). INTELLiVENT-ASV was used with default target settings. If PEEP was above 16 cmH2O, the recruitment strategy used transpulmonary pressure as a reference, and ΔPL and MPL were computed. Measurements were made once for each patient.

RESULTS

Of the 255 patients included, 98 patients were classified as normal-lungs, 28 as COPD, and 129 as ARDS patients. The median ΔP was 8 (7 - 10), 10 (8 - 12), and 9 (8 - 11) cmH2O for normal-lungs, COPD, and ARDS patients, respectively. The median MP was 9.1 (4.9 - 13.5), 11.8 (8.6 - 16.5), and 8.8 (5.6 - 13.8) J/min for normal-lungs, COPD, and ARDS patients, respectively. For the 19 patients managed with transpulmonary pressure ΔPL was 6 (4 - 7) cmH2O and MPL was 3.6 (3.1 - 4.4) J/min.

CONCLUSIONS

In this short term observation study, INTELLiVENT-ASV selected ΔP and MP considered in safe ranges for lung protection. In a subgroup of ARDS patients, the combination of a recruitment strategy and INTELLiVENT-ASV resulted in an apparently safe ΔPL and MPL.

Driving pressure and survival in the acute respiratory distress syndrome.

Amato MB, Meade MO, Slutsky AS, et al. Driving pressure and survival in the acute respiratory distress syndrome. N Engl J Med. 2015;372(8):747-755. doi:10.1056/NEJMsa1410639

Link to article

BACKGROUND

Mechanical-ventilation strategies that use lower end-inspiratory (plateau) airway pressures, lower tidal volumes (VT), and higher positive end-expiratory pressures (PEEPs) can improve survival in patients with the acute respiratory distress syndrome (ARDS), but the relative importance of each of these components is uncertain. Because respiratory-system compliance (CRS) is strongly related to the volume of aerated remaining functional lung during disease (termed functional lung size), we hypothesized that driving pressure (ΔP=VT/CRS), in which VT is intrinsically normalized to functional lung size (instead of predicted lung size in healthy persons), would be an index more strongly associated with survival than VT or PEEP in patients who are not actively breathing.

METHODS

Using a statistical tool known as multilevel mediation analysis to analyze individual data from 3562 patients with ARDS enrolled in nine previously reported randomized trials, we examined ΔP as an independent variable associated with survival. In the mediation analysis, we estimated the isolated effects of changes in ΔP resulting from randomized ventilator settings while minimizing confounding due to the baseline severity of lung disease.

RESULTS

Among ventilation variables, ΔP was most strongly associated with survival. A 1-SD increment in ΔP (approximately 7 cm of water) was associated with increased mortality (relative risk, 1.41; 95% confidence interval [CI], 1.31 to 1.51; P<0.001), even in patients receiving "protective" plateau pressures and VT (relative risk, 1.36; 95% CI, 1.17 to 1.58; P<0.001). Individual changes in VT or PEEP after randomization were not independently associated with survival; they were associated only if they were among the changes that led to reductions in ΔP (mediation effects of ΔP, P=0.004 and P=0.001, respectively).

CONCLUSIONS

We found that ΔP was the ventilation variable that best stratified risk. Decreases in ΔP owing to changes in ventilator settings were strongly associated with increased survival. (Funded by Fundação de Amparo e Pesquisa do Estado de São Paulo and others.).

Effect of Lung Recruitment and Titrated Positive End-Expiratory Pressure (PEEP) vs Low PEEP on Mortality in Patients With Acute Respiratory Distress Syndrome: A Randomized Clinical Trial.

Writing Group for the Alveolar Recruitment for Acute Respiratory Distress Syndrome Trial (ART) Investigators, Cavalcanti AB, Suzumura ÉA, et al. Effect of Lung Recruitment and Titrated Positive End-Expiratory Pressure (PEEP) vs Low PEEP on Mortality in Patients With Acute Respiratory Distress Syndrome: A Randomized Clinical Trial. JAMA. 2017;318(14):1335-1345. doi:10.1001/jama.2017.14171

Link to article

Importance

The effects of recruitment maneuvers and positive end-expiratory pressure (PEEP) titration on clinical outcomes in patients with acute respiratory distress syndrome (ARDS) remain uncertain.

Objective

To determine if lung recruitment associated with PEEP titration according to the best respiratory-system compliance decreases 28-day mortality of patients with moderate to severe ARDS compared with a conventional low-PEEP strategy.

Design, Setting, and Participants

Multicenter, randomized trial conducted at 120 intensive care units (ICUs) from 9 countries from November 17, 2011, through April 25, 2017, enrolling adults with moderate to severe ARDS.

Interventions

An experimental strategy with a lung recruitment maneuver and PEEP titration according to the best respiratory-system compliance (n = 501; experimental group) or a control strategy of low PEEP (n = 509). All patients received volume-assist control mode until weaning.

Main Outcomes and Measures

The primary outcome was all-cause mortality until 28 days. Secondary outcomes were length of ICU and hospital stay; ventilator-free days through day 28; pneumothorax requiring drainage within 7 days; barotrauma within 7 days; and ICU, in-hospital, and 6-month mortality.

Results

A total of 1010 patients (37.5% female; mean [SD] age, 50.9 [17.4] years) were enrolled and followed up. At 28 days, 277 of 501 patients (55.3%) in the experimental group and 251 of 509 patients (49.3%) in the control group had died (hazard ratio [HR], 1.20; 95% CI, 1.01 to 1.42; P = .041). Compared with the control group, the experimental group strategy increased 6-month mortality (65.3% vs 59.9%; HR, 1.18; 95% CI, 1.01 to 1.38; P = .04), decreased the number of mean ventilator-free days (5.3 vs 6.4; difference, -1.1; 95% CI, -2.1 to -0.1; P = .03), increased the risk of pneumothorax requiring drainage (3.2% vs 1.2%; difference, 2.0%; 95% CI, 0.0% to 4.0%; P = .03), and the risk of barotrauma (5.6% vs 1.6%; difference, 4.0%; 95% CI, 1.5% to 6.5%; P = .001). There were no significant differences in the length of ICU stay, length of hospital stay, ICU mortality, and in-hospital mortality.

Conclusions and Relevance

In patients with moderate to severe ARDS, a strategy with lung recruitment and titrated PEEP compared with low PEEP increased 28-day all-cause mortality. These findings do not support the routine use of lung recruitment maneuver and PEEP titration in these patients.

Trial Registration

clinicaltrials.gov Identifier: NCT01374022.

How to set ASV® correctly for a (COVID-19) ARDS patient

How does ASV work?

Patient information and initial settings

Adjustments

Assess recruitability

Footnotes

References

NIH NHLBI ARDS Clinical Network Mechanical Ventilation Protocol Summary

Driving pressure automatically selected by INTELLiVENT-ASV in ICU patients

Airway and transpulmonary driving pressures and mechanical powers selected by INTELLiVENT-ASV in passive, mechanically ventilated ICU patients.

Driving pressure and survival in the acute respiratory distress syndrome.

Effect of Lung Recruitment and Titrated Positive End-Expiratory Pressure (PEEP) vs Low PEEP on Mortality in Patients With Acute Respiratory Distress Syndrome: A Randomized Clinical Trial.

Effect of Lung Recruitment and Titrated Positive End-Expiratory Pressure (PEEP) vs Low PEEP on Mortality in Patients With Acute Respiratory Distress Syndrome: A Randomized Clinical Trial.

Downloads for How to set ASV® correctly for a (COVID-19) ARDS patient

P/V Tool® Pro Benutzerhandbuch Beurteilung der Rekrutierbarkeit der Lunge und Durchführung von Recruitmentmanövern bei erwachsenen Patienten

P/V Tool® Pro User guide User Guide

P/V Tool® Pro Guía de usuario

P/V Tool® Pro Guide de l’utilisateur

P/V Tool® Pro Guida utente

Инструмент P/V Tool® Pro Руководство по эксплуатации

P/V Tool® Pro 用户指南

P/V Tool® Pro ユーザガイド 成人患者での肺評価とリクルートメント

Kurzübersichtskarte zum P/V Tool® Pro

P/V Tool® Pro Quick Reference Card

Hoja de referencia rápida de P/V Tool® Pro

Carte de référence rapide P/V Tool® Pro

Scheda di riferimento rapido di P/V Tool® Pro

Cartão de Referência Rápida P/V Tool® Pro

Краткая справочная карта инструмента P/V Tool® Pro

P/V Tool® Pro 快速参考卡

Related articles. Get a deeper look

COVID-19: Respiratory treatment in critical care – recommendations

How to set INTELLiVENT-ASV for a (COVID-19) ARDS patient

P/V Tool® Pro ユーザガイド成人患者での肺評価とリクルートメント