Intensivmedizin und Notfallmedizin

, Volume 46, Issue 6, pp 441–446 | Cite as

Comparison of automated protocol-based versus non-protocol-based physician-directed weaning from mechanical ventilation

A controlled clinical trial
  • C. Stahl
  • G. Dahmen
  • A. Ziegler
  • E. Muhl


Rationale and objectives

In the weaning of patients from mechanical ventilation by gradually reducing pressure support ventilation (PSV), an automated computerized system recently proved to be superior to traditional physician-directed weaning. The aim of this study was to replicate these findings when weaning a broad surgical intensive care unit (ICU) patient population off the ventilator.

Methods and measurements

Sixty patients requiring mechanical ventilation over 24 h were randomized to either automated (n = 30) or physician-directed (n = 30) weaning. The primary endpoint was duration of weaning. Secondary endpoints were duration of mechanical ventilation, length of ICU stay, reintubation rates, and workload for staff.


Weaning duration did not differ significantly between the computer-driven group and the physician-directed group (0.64 vs. 2.33 d, 95%CI: -0.10 to 2.15, p = 0.167). No significant differences were detected for any secondary endpoint except the workload for PSV settings, which was lower in the computer-driven weaning group (0.0 vs. 0.15 settings/h, p < 0.0001). The trial was stopped early because sample size recalculations based on a Pocock design showed it would be pointless to continue.


Computer-driven weaning was not different from traditional physician-directed weaning from mechanical ventilation. Therefore, it cannot be recommended for routine use in a broad surgical ICU patient population.


Intensive care Ventilator weaning Weaning protocols Computer-assisted therapy 

Vergleich von automatisierter protokollbasierter mit arztgesteuerter nicht protokollbasierter Entwöhnung vom Beatmungsgerät

Eine kontrollierte klinische Studie


Begründung und Zielsetzung

Ein automatisiertes Entwöhnungssystem erwies sich kürzlich gegenüber herkömmlicher arztgesteuerter Entwöhnung vom Beatmungsgerät überlegen. Beide Verfahren basierten auf der schrittweisen Reduktion von druckunterstützter Beatmung („pressure support ventilation“). Durch die vorliegende Studie sollte die Wiederholbarkeit dieses Ergebnisses an einem breiten chirurgischen Intensivpatientenkollektiv überprüft werden.


Es wurden 60 Patienten mit einer vorhergehenden kontrollierten Beatmungsdauer von mindestens 24 h randomisiert. Jeweils 30 Patienten wurden automatisiert und arztgesteuert entwöhnt. Primärer Endpunkt war die Entwöhnungsdauer. Sekundäre Endpunkte waren die Dauer der mechanischen Beatmung, die Intensivaufenthaltsdauer, die Reintubationsrate und die Arbeitsbelastung des medizinischen Personals.


Die Entwöhnungsdauer unterschied sich nicht signifikant zwischen dem automatisiert und arztgesteuert entwöhnten Patientenkollektiv (0,64 vs. 2,33 Tage, 95%-KI: –0,10–2,15, p=0,167). Auch bei den sekundären Endpunkten konnte kein signifikanter Unterschied beobachtet werden. Eine Ausnahme stellte hier die Arbeitsbelastung bei den PSV-Einstellungen dar, die in der computergesteuerten Gruppe signifikant geringer war (0,0 vs. 0,15 Einstellungen pro Stunde, p<0,0001). Die Studie wurde vorzeitig gestoppt, da auf einem Pocock-Design basierende Rekalkulationen zeigten, dass eine Fortführung sinnlos wäre.


Automatisierte Entwöhnung unterschied sich in den wesentlichen Endpunkten nicht signifikant von konventionell arztgesteuerter Entwöhnung und kann daher nicht generell empfohlen werden.


Intensivmedizin Entwöhnung vom Beatmungsgerät Entwöhnungsprotokolle Computerunterstützte Therapie 


Conflict of interest

The corresponding author states that there are no conflicts of interest.


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Copyright information

© Spinger 2009

Authors and Affiliations

  1. 1.Department of SurgeryUniversity Hospital of Schleswig-Holstein, Campus LübeckLübeckDeutschland
  2. 2.Institute of Medical Biometry and StatisticsUniversity of LübeckLübeckDeutschland

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