Neste 45 minutt Problemkompleks ARDS Gjennomgang av APRV Kort om EBM for maveleie og APRV Fasit

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2 Neste 45 minutt Problemkompleks ARDS Gjennomgang av APRV Kort om EBM for maveleie og APRV Fasit

3 Kvinne 41 år 1. dag

4 2. dag

5 3. dag

6 Klinisk status 3. dag? BiPAP 30 og PEEP 15 gir TV 410 ml PaCO2 9,9 kpa FiO2 0,9 gir PaO2 7,3 kpa og SpO2 83% Sedert til MAAS 1 Ved hosting eller motarbeidet faller SpO2 Noradrenalin infusjon Hva kan gjøres?

7 Hva er ARDS Oxygeneringssvikt PaO2/FiO2 ratio < 26 kpa Bilaterale lungefortetninger Wedge trykk < 18 mmhg eller fravær av venstre ventrikkel svikt Sykdom som utløsende årsak Ofte infeksjon

8 Hva vil skje ved din avdeling? Akseptere respiratorsetting og blodgass Overflytting til annet sykehus Maveleie Oscillering ECMO Annet

9 Prinsipper for ARDS behandling Behandle utløsende sykdom Infeksjonen saneres Oxygenering av pasienten Hva er akseptabelt? Ikke skade lungene med ventilasjonen Hva vet vi?

10 Strategi for ventilasjon ved ARDS Begrenset tidalvolum 6 ml/kg kroppsvekt Noe PEEP Begrense transpulmonalt trykk

11 Stikkord i forbindelse med sekunder lungeskade Barotraume Volumtraume Atelektraume Baby lung Alveoler kollaps Oxygentoksisitet

12 Hva innvirker på oxygenering? FiO2 eller FiAlvO2 Middel luftveistrykk Graden av shunt

13 Hvordan blir ventilasjonen? Atelektaser dannes til tross for PEEP Man bruker høye trykk Man godtar høy PaCO2 Pasienten trenger dyp sedasjon Ingen spontanventilasjon

14 Airway pressure release ventilation

15 Hvem... Har aldri hørt om APRV Har hørt om APRV Kjenner godt til APRV Har brukt APRV

16 APRV hva er det? Ventilasjonsform hvor MAiP holdes høy Inkluderer spontanventilasjon CPAP med regelmessige korte fall i luftveistrykk

17 Hvor virker APRV Reduksjon istedenfor økning av LVT for å oppnå ventilasjon Sikrer både oxygenering og CO2 fjerning Tillater ubegrenset spontanpusting

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20 Når fungere det best Ofte god respons ved lungesykdom med potensial for rekruttering Altså tilstander med nedsatt compliance ARDS ALI IRDS

21 MAiP er viktig Direkte korrelasjon mellom MAiP, lungevolum og oksygenering APRV gir passende lungevolum Lang P Høy, kort P Lav Delvis lunge tømming, mest raske avsnitt Bibehold rekruttering

22 Hvordan setter vi det opp? P Høy 4 cm vann over MAiP Alternativ = platå trykk i konvensjonell ventilasjon Voksne < 30 cm vann T Høy 4 sec P Lav alltid 0

23 Hvordan setter vi det opp? (2) T Lav settes slik at målt P Lav ikke kommer ned til 0 Voksne 0,8 1,2 sec Hvis T Lav for lang Derekruttering og atelektaser T Lav for kort Inadekvat utpusting med dødromsventilasjon, økt PaCO2 og hemodynamiske problemer Se på volumkurven for å velge T lav

24 APRV gass fløde

25 Velge T Lav

26 Hvordan bedre oxygenering? Optimaliser utåndet volum PEFR (Peak expiratory gas flow) P Lav skal settes til 50-75% Økt MAiP Øk P Høy Øk T Høy Øke FiO2?

27 Hvordan bedre CO2 utskillelse? Tillat spontanpust Optimaliser Release Volume Øk T Lav (PEFR > 75 %) Senk T Lav (PEFR < 50%) Øk alveoler ventilasjon Øk P Høy Øk både P og T høy Øk minutt ventilasjon forsiktig Øk P Høy og senk T Høy samtidig

28 Hva med ATC? Ingen skadelig effekt Små studier viser positiv effekt

29 Erfaringer fra egen avdeling I starten stor skepsis Forbausende god effekt Mest brukt modus ved alvorlig ARDS Økende bruk også ved moderat lungesvikt Datasamling pågår Ikke flyttet dårlig ARDS siste to år

30 Hvordan velge klinisk praksis? EBM Personlige erfaringer Guidelines Logiske overveielser Lokale tradisjoner Gjennomførbarhet i praksis Faremomenter og invasivitet

31 The utilities in Clinical Queries are not intended to supply a comprehensive literature search. They are designed to provide information on those few "good" articles which will help the clinician make informed health-related decisions. This page provides the following specialized PubMed searches for clinicians: * Search by Clinical Study Category * Find Systematic Reviews

32 The effect of prone positioning in acute respiratory distress syndrome or acute lung injury: a metaanalysis. Areas of uncertainty and recommendations for research. Abroug F, Ouanes-Besbes L, Elatrous S, Brochard L. Service de Réanimation Polyvalente, CHU F. Bourguiba, 5000, Monastir, Tunisia, f.abroug@rns.tn. OBJECTIVE: To compare the effects of ventilation in prone and in supine position in patients with acute lung injury/acute respiratory distress syndrome (ALI/ARDS). DESIGN: Meta-analysis of randomised controlled trials. DATA SOURCES: BioMedCentral, PubMed, CINAHL, and Embase (to November 2007), with additional information from authors. MEASUREMENTS AND RESULTS: From selected randomised controlled trials comparing positioning in ALI/ARDS we extracted data concerning study design, disease severity, clinical outcomes, and adverse events. Five trials including 1,372 patients met the inclusion criteria for mortality analysis; one trial was added to assess the effects on acquisition of ventilator-associated pneumonia (VAP). The included trials were significantly underpowered and enrolled patients with varying severity. Prone positioning duration and mechanical ventilation strategy were not standardised across studies. Using a fixedeffects model, we did not find a significant effect of prone positioning (proning) on mortality (odds ratio 0.97, 95% confidence interval ). The PaO(2)/FiO(2) ratio increased significantly more with proning (weighted means difference 25 mmhg, p[symbol: see text]<[symbol: see text] ). Proning was associated with a non-significant 23% reduction in the odds of VAP (p[symbol: see text]=[symbol: see text]0.09), and with no increase in major adverse airway complications: OR 1.01, 95% CI Length of intensive care unit stay was marginally and not significantly increased by proning. CONCLUSIONS: Prone position is not associated with a significant reduction in mortality from ALI/ARDS despite a significant increase in PaO(2)/FiO(2), is safe, and tends to decrease VAP. Published studies exhibit substantial clinical heterogeneity, suggesting that an adequately sized study optimising the duration of proning and ventilation strategy is warranted to enable definitive conclusions to be drawn.

33 Effect of prone positioning in patients with acute respiratory distress syndrome: a meta-analysis. Alsaghir AH, Martin CM. Division of Critical Care, Department of Medicine, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada. OBJECTIVE: To review the effectiveness of prone position as compared with supine position, with respect to mortality, improvement in oxygenation, number of days on mechanical ventilation, and ventilator-associated pneumonia. DATA SOURCE: PubMed, EMBASE, Cochrane database, and a manual review of article bibliographies. STUDY SELECTION: Randomized controlled trials comparing > or = 6 hrs of prone position with supine position in adult patients with adult respiratory distress syndrome. DATA EXTRACTION: Two reviewers independently performed assessment of abstracts and study quality. Data were combined in a meta-analysis using random-effect models. MAIN FINDINGS: Five studies were identified. We did not find any significant differences in intensive care unit mortality (three studies, 466 patients; odds ratio, 0.79; 95% confidence interval [CI], ), 28- to 30-day mortality (three studies, 1,231 patients; odds ratio, 0.95; 95% CI, ), and 90-day mortality (four studies, 1,271 patients; odds ratio, 0.99; 95% CI, ). However, prone position showed significant reduction in mortality in patients with higher illness severity (two studies, 113 patients; odds ratio, 0.29; 95% CI, ). Prone positioning also showed significant and persistent improvement in the PaO2/FiO2 ratio in early (12 hrs to 2 days) (four studies, 866 patients; weighted mean difference, 51.5; 95% CI, ), intermediate (4 days) (three studies, 754 patients; weighted mean difference, 43.87; 95% CI, ), and late (10 days) period (four studies, 833 patients; weighted mean difference, 24.89; 95% CI, ). There were no significant differences in number of days on mechanical ventilation (two studies, 831 patients; weighted mean difference, days; 95% CI, to 0.72) or incidence of ventilator-associated pneumonia (three studies, 967 patients; weighted mean difference, 0.78%; 95% CI, ). CONCLUSION: Based on the results of this meta-analysis, prone position improves oxygenation in patients with adult respiratory distress syndrome, and in patients with higher illness severity, it also may reduce mortality.

34 Airway pressure release ventilation as a primary ventilatory mode in acute respiratory distress syndrome. Varpula T, Valta P, Niemi R, Takkunen O, Hynynen M, Pettilä VV. Department of Anesthesiology and Intensive Care Medicine, Jorvi Hospital, Helsinki University Hospital, Espoo, Finland. tero.varpula@hus.fi BACKGROUND: Airway pressure release ventilation (APRV) is a ventilatory mode, which allows unsupported spontaneous breathing at any phase of the ventilatory cycle. Airway pressure release ventilation as compared with pressure support (PS), another partial ventilatory mode, has been shown to improve gas exchange and cardiac output. We hypothesized whether the use of APRV with maintained unsupported spontaneous breathing as an initial mode of ventilatory support promotes faster recovery from respiratory failure in patients with acute respiratory distress syndrome (ARDS) than PS combined with synchronized intermittent ventilation (SIMV-group). METHODS: In a randomized trial 58 patients were randomized to receive either APRV or SIMV after a predefined stabilization period. Both groups shared common physiological targets, and uniform principles of general care were followed. RESULTS: Inspiratory pressure was significantly lower in the APRV-group (25.9 +/- 0.6 vs /- 0.7 cmh2o) within the first week of the study (P = 0.007). PEEP-levels and physiological variables (PaO2/FiO2-ratio, PaCO2, ph, minute ventilation, mean arterial pressure, cardiac output) were comparable between the groups. At day 28, the number of ventilator-free days was similar (13.4 +/- 1.7 in the APRV-group and /- 1.5 in the SIMV-group), as was the mortality (17% and 18%, respectively). CONCLUSION: We conclude that when used as a primary ventilatory mode in patients with ARDS, APRV did not differ from SIMV with PS in clinically relevant outcome. Copyright 2004 Acta Anaesthesiologica Scandinavica

35 Long-term effects of spontaneous breathing during ventilatory support in patients with acute lung injury. Putensen C, Zech S, Wrigge H, Zinserling J, Stüber F, Von Spiegel T, Mutz N. Department of Anesthesiology and Intensive Care Medicine Bonn Improved gas exchange has been observed during spontaneous breathing with airway pressure release ventilation (APRV) as compared with controlled mechanical ventilation. This study was designed to determine whether use of APRV with spontaneous breathing as a primary ventilatory support modality better prevents deterioration of cardiopulmonary function than does initial controlled mechanical ventilation in patients at risk for acute respiratory distress syndrome (ARDS). Thirty patients with multiple trauma were randomly assigned to either breathe spontaneously with APRV (APRV Group) (n = 15) or to receive pressure-controlled, time-cycled mechanical ventilation (PCV) for 72 h followed by weaning with APRV (PCV Group) (n = 15). Patients maintained spontaneous breathing during APRV with continuous infusion of sufentanil and midazolam (Ramsay sedation score [RSS] of 3). Absence of spontaneous breathing (PCV Group) was induced with sufentanil and midazolam (RSS of 5) and neuromuscular blockade. Primary use of APRV was associated with increases (p < 0.05) in respiratory system compliance (CRS), arterial oxygen tension (PaO2), cardiac index (CI), and oxygen delivery (DO2), and with reductions (p < 0.05) in venous admixture (QVA/QT), and oxygen extraction. In contrast, patients who received 72 h of PCV had lower CRS, PaO2, CI, DO2, and Q VA/Q T values (p < 0.05) and required higher doses of sufentanil (p < 0.05), midazolam (p < 0.05), noradrenalin (p < 0.05), and dobutamine (p < 0.05). CRS, PaO2), CI and DO2 were lowest (p < 0.05) and Q VA/Q T was highest (p < 0.05) during PCV. Primary use of APRV was consistently associated with a shorter duration of ventilatory support (APRV Group: 15 +/- 2 d [mean +/- SEM]; PCV Group: 21 +/- 2 d) (p < 0.05) and length of intensive care unit (ICU) stay (APRV Group: 23 +/- 2 d; PCV Group: 30 +/- 2 d) (p < 0.05). These findings indicate that maintaining spontaneous breathing during APRV requires less sedation and improves cardiopulmonary function, presumably by recruiting nonventilated lung units, requiring a shorter duration of ventilatory support and ICU stay.

36 Fasit Hverken maveleie eller APRV har dokumentert effekt på mortalitet Ved kritisk lungesvikt kan man ikke la være å forsøke å bedre oxygenering Ikke alle avdelinger har mulighet for avansert behandling Maveleie resurskrevende APRV fungerer og er ikke skadelig

37 Further studies...