Clinical Relevance of Classification According to Weaning Difficulty

Abstract

OBJECTIVE: To evaluate the clinical relevance of the weaning from mechanical ventilation classification system derived from the 2005 international consensus conference, in patients who receive mechanical ventilation for more than 48 hours, and evaluate its correlation with prognosis. METH-ODS: We conducted a retrospective cohort study in a 12-bed intensive care unit (ICU) in a teaching hospital. We included patients who required > 48 hours of mechanical ventilation and who passed a spontaneous breathing trial (SBT). Weaning and sedation were monitored according to standardized protocol-directed procedures. We collected data on physiological characteristics, mechanical ventilation duration, ICU and hospital stay, and mortality from the medical records database. We assessed one-year mortality with a prospective, standardized method. Multivariate logistic regression was performed to evaluate the association between weaning categories and outcome. RE-SULTS: We included 329 ventilation episodes, in which 115 patients passed at least one SBT. Thirty-four patients (30%) succeeded in their first SBT (simple weaning group), 47 patients (40%) succeeded in their 2nd or 3rd SBT or in less than 7 days of weaning (the difficult weaning group), and 34 patients (30%) required more than 3 SBTs or more than 7 days of weaning (the prolonged weaning group). There were significant differences in ICU and hospital mortality between the simple, difficult, and prolonged-weaning groups. Prolonged weaning was an independent risk factor for longer ICU stay (odds ratio 15.11, 95% CI 1.61-141.91, P ‫؍‬ .01) and hospital mortality (odds ratio 3.66, 95% CI 0.99 -13.51). However, the weaning process did not impact one-year mortality (odds ratio 2.61, 95% CI 0.82-8.35). CONCLUSIONS: The new weaning classification system is clinically relevant and correlates to ICU and hospital mortality, but not to one-year mortality.

The Vexing Problem of Ventilator-Associated Pneumonia: Observations on Pathophysiology, Public Policy, and Clinical Science

“…99 In a contemporaneous survey of clinicians, the average duration of weaning ranged from 5 to 18 d, with the longest duration associated with synchronized intermittent mandatory ventilation combined with pressure support ventilation. 100 However, more contemporary studies have reported that the average duration of mechanical ventilation now is ϳ5-7 d. 45,46,[101][102][103] This invites speculation that the incidence of VAP likely was much greater before modern weaning and sedation practices.…”

Incidência e fatores associados ao desmame simples, difícil e prolongado em uma unidade de terapia intensiva

“…Este resultado é comparável com o do presente estudo. Tonnelier et al 23 , realizaram um estudo recente de coorte retrospectivo na França com 115 pacientes que permaneceram em VM por mais de 48 horas e que realizaram o TRE. Evidenciaram um índice de desmame simples, difícil e prolongado de 30, 40 e 30%, respectivamente, e constataram que o desmame prolongado foi um fator independente de risco para maior mortalidade na UTI (odds ratio: 15,11; IC 95%: 1,61-141,91; p=0,01) e mortalidade hospitalar (odds ratio: 3,66; IC 95%: 0,99-13,51; p=0,05), confirmando assim a relevância clínica das novas categorias do desmame ventilatório no prognóstico dos pacientes.…”

“…A incidência de PAV foi superior no grupo de pacientes com desmame prolongado. Este mesmo achado foi encontrado por Tonnelier et al 23 , os quais encontraram uma Artigo originAl incidência de PAV de 62% no grupo desmame prolongado. A PAV é a infecção nosocomial mais comum no ambiente de cuidados intensivos.…”

The Process of Weaning from Mechanical Ventilation

“…A number of studies [57][58][59][60][61][62] have evaluated this classification. In these studies, the incidence of the simple weaning group was 30-67% of all patients in whom an SBT was attempted (Fig.…”

“…A summary of these studies [57][58][59][60][61][62] indicates that simple and difficult weaning groups are similar in terms of mortality, re-intubation, tracheostomy, and ICU stay ( Table 2). The prolonged weaning group, however, has been associated with worse outcomes and higher mortality (Table 2).…”