R2 김재민 / Prof. 박명재 Journal conference 1

Rationale:  Fluid overload - difficult weaning from mechanical ventilation  B-type natriuretic peptide (BNP) - tool for predicting and detecting weaning failure of cardiovascular origin Objectives:  fluid management guided by daily BNP plasma concentrations vs. empirical therapy by clinical acumen BACKGROUND BACKGROUND 2

Weaning : at least 40% of total duration of mechanical ventilation Numerous reports suggests : PCWP ↓, minimize (+) fluid balance → improve outcomes fluid overload → weaning failure of cardiac origin BNP : cardiac biomarker from cardiomyocytes in wall stress ↑ predict weaning failure BACKGROUND BACKGROUND 3

Hypothesis: fluid management guided by daily BNP → would improve outcomes compared with empirical therapy dictated by clinical acumen international, multicenter, randomized controlled trial To standardize the weaning process : using a computer-driven automated weaning system (AWS) (Evita Smart Care system; Drager Medical, Lubeck, Germany) BACKGROUND BACKGROUND 4

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Hypothesis: fluid management guided by daily BNP → would improve outcomes compared with empirical therapy dictated by clinical acumen international, multicenter, randomized controlled trial To standardize the weaning process : using a computer-driven automated weaning system (AWS) (Evita Smart Care system; Drager Medical, Lubeck, Germany) BACKGROUND BACKGROUND 7

Study protocol Patients in CMV, pressure support(PS) test (+) PS test: changing the ventilator mode to PS without changing FIO2 or PEEP Randomization & masking (1) COPD (2) LVD : left ventricular dysfunction(EF < 45%) (3) absence of both All randomized patients were ventilated using the AWS monitored until discharge or day 60 after randomization METHODS METHODS 8

BNP assay sample was collected every morning in all randomized patients one device: display the BNP results the other: did not display the BNP results Fluid and Electrolyte Management METHODS METHODS 9 - blinded to the BNP results - usual care - with no explicit protocol Control group If BNP ≥ 200 pg/ml ☞ fluid intake restriction : baseline < 500 ml/24 h : TPN < 1,000 ml/24 h) ☞ furosemide : iv 10 ~ 30 mg q3hr : urine output 4.5~9 ml/kg/3 h) BNP-guided group

Ventilatory Management - using the AWS in both groups - sedation was stopped, possible(analgesia could be continued) - The AWS gradually decrease the PS level - Assist-control ventilation was resumed(respiratory worsening) - RR > 40 - hypoxemia(FIO2 >60% and PEEP> 8 cmH2O for SpO2 > 90%) - tidal volume target : 6 ml/kg (predicted body weight) METHODS METHODS 10

End points - Primary time(randomization ~ successful extubation) - secondary: time to first extubation time to successful weaning from invasive and noninvasive ventilation ventilator- free days ICU & hospital length of stay mortality on Day 60 METHODS METHODS 11

RESULTS ~ Control : 152BNP-guided : 154

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17 RESULTS Time to first extubation Time to successful extubation Time to successful weaning from invasive & noninvasive ventilation P < 0.05

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CONCLUSIONS CONCLUSIONS BNP-driven fluid management during weaning from mechanical ventilation (vs. physician-guided fluid management) → ↓ duration of weaning → without increasing adverse events → especially in patients with LVD → no significant differences in mortality rate or length of stay 19