Epidemiology of Weaning Outcome according to a New Definition. The WIND Study.
The weaning process concerns all patients receiving mechanical ventilation. A previous classification into simple, prolonged, and difficult weaning ignored weaning failure and presupposed the use of spontaneous breathing trials.



To describe the weaning process, defined as starting with any attempt at separation from mechanical ventilation and its prognosis, according to a new operational classification working for all patients under ventilation.



This was a multinational prospective multicenter observational study over 3 months of all patients receiving mechanical ventilation in 36 intensive care units, with daily collection of ventilation and weaning modalities. Pragmatic definitions of separation attempt and weaning success allowed us to allocate patients in four groups.



A total of 2,729 patients were enrolled. Although half of them could not be classified using the previous definition, 99% entered the groups on the basis of our new definition as follows: 24% never started a weaning process, 57% had a weaning process of less than 24 hours (group 1), 10% had a difficult weaning of more than 1 day and less than 1 week (group 2), and 9% had a prolonged weaning duration of 1 week or more (group 3). Duration of ventilation, intensive care unit stay, and mortality (6, 17, and 29% for the three groups, respectively) all significantly increased from one group to the next. The unadjusted risk of dying was 19% after the first separation attempt and increased to 37% after 10 days.



A new classification allows us to categorize all weaning situations. Every additional day without a weaning success after the first separation attempt increases the risk of dying.
1 Medical Intensive Care Unit and.|2 Normandie Univ, UNIROUEN, EA 3830, Rouen, France.
Gaëtan
G
Béduneau
3 AP-HP, Hôpital Tenon, Unité de Réanimation Médico-Chirurgicale, Pôle Thorax Voies Aériennes, Groupe Hospitalier des Hôpitaux Universitaires de l'Est Parisien, Paris, France.|4 Sorbonne Universités, Université Pierre et Marie Curie, Paris 06, Paris, France.|5 Unité Mixte de Recherche 1153, INSERM, Sorbonne Paris Cité, Epidémiologie Clinique et Statistiques pour la Recherche en Santé Team, Université Paris Diderot, Paris, France.
Tài
T
Pham
6 Medical Intensive Care Unit, Centres Hospitaliers Universitaires Henri Mondor, APHP Paris, Paris, France.
Frédérique
F
Schortgen
7 Department of Medical Intensive Care and.|8 Intensive Care and Burn Unit, University Hospital of Lausanne, Lausanne, Switzerland.
Lise
L
Piquilloud
9 Cardio Thoracic and Vascular Intensive Care Unit, Centres Hospitaliers Universitaires Amiens-Picardie, Amiens, France.|10 INSERM U1088, CURS, Université Jules Verne, Picardie, France.
Elie
E
Zogheib
11 Medical Intensive Care Unit, Hôtel-Dieu, University Hospital of Nantes, Nantes, France.
Maud
M
Jonas
12 Intensive Care Unit, Hospital of Le Mans, Le Mans, France.
Fabien
F
Grelon
13 Medical Intensive Care Unit Regional Medical Center, Orleans, France.
Isabelle
I
Runge
14 INSERM, U1075, Caen, France.|15 Université de Caen, Caen, France.|16 Service de Réanimation Médicale, Centre Hospitalier Régional Universitaire Caen, Caen, France.|17 Service de Réanimation Médicale, Centres Hospitaliers Universitaires Grenoble Alpes, Grenoble, France.
Nicolas Terzi
1 Medical Intensive Care Unit and.
Steven
S
Grangé
18 Medical Intensive Care Unit, Mulhouse Regional Hospital, Mulhouse, France.
Guillaume
G
Barberet
19 Surgical Intensive Care, Rouen University Hospital, Rouen, France.
Pierre-Gildas
PG
Guitard
20 Service de Réanimation Médicale, Centres Hospitaliers Universitaires de Poitiers, Poitiers, France.|21 INSERM, CIC-1402, Équipe 5 ALIVE, Poitiers, France.|22 Faculté de Médecine et de Pharmacie de Poitiers, Université de Poitiers, Poitiers, France.
Jean-Pierre
JP
Frat
6 Medical Intensive Care Unit, Centres Hospitaliers Universitaires Henri Mondor, APHP Paris, Paris, France.
Adrien
A
Constan
23 Department of Clinical Research and Innovation, University Hospital of Angers, Angers, France.
Jean-Marie
JM
Chretien
24 Servei de Medicina Intensiva, Hospital de Sant Pau, Barcelona, Spain.
Jordi
J
Mancebo
7 Department of Medical Intensive Care and.
Alain
A
Mercat
25 Annecy Genevois General Hospital, Annecy, France.
Jean-Christophe M
JM
Richard
26 Keenan Research Centre, Li Ka Shing Knowledge Institute, Saint Michael's Hospital, Toronto, Ontario, Canada; and.|27 Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, Ontario, Canada.
Laurent
L
Brochard
D005260:Female; D005602:France; D006801:Humans; D007362:Intensive Care Units; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care / Q000379:methods* / Q000706:statistics & numerical data*; D011446:Prospective Studies; D013030:Spain; D013557:Switzerland; D013997:Time Factors; D015300:Ventilator Weaning / Q000145:classification / Q000379:methods* / Q000706:statistics & numerical data*
mechanical ventilation; outcome; separation attempt; weaning