Comptes rendus de l’Acade'mie bulgare des Sciences, Vol 66, No10, pp.1385-1392

Generalized Net Model of a Protocol for Weaning from Mechanical Ventilation

Lyudmila Todorova, Peter Vassilev, Mikhail Matveev, Vessela Krasteva, Irena Jekova, Stefan Hadjitodorov, Georgi Georgiev, Stoyan Milanov


In the present work an attempt is made to evaluate objectively the ventilated patients’ condition from the monitored parameters (standard physiological parameters, parameters of the ventilation and respiratory mechanics, parameters of the gas exchange and energy expenditure) in order to determine their readiness for weaning from mechanical ventilation support. This research is a step in improving the care for ventilated patients in order to decrease the period of ventilation support. In the Central Intensive Care Unit, University Emergency Hospital “N. I. Pirogov” an investigation is conducted, with stages described in detail in the paper. A generalized model represents these phases. The decision criteria and the results of their application are evaluated by the so-constructed generalized net and a validity score is updated for each rule to be used in further considerations. The accuracy of the predictive rules has been estimated by calculating the sensitivity, specificity, the positive- and negative predictive value. Due to the relatively small number of patients, the developed GN-model will be refined in the course of the continuing investigation at the Central Intensive Care Unit, University Emergency Hospital “N. I. Pirogov”.

Key words: generalized nets, weaning from mechanical ventilation, decision criteria