Acceptable respiratory physiologic limits for children during weaning from mechanical ventilation.

Objective: The aim of this survey was to characterize the physiological limits considered appropriate during weaning from mechanical ventilation in children.

Design: Two hundred twenty-two (222) intensivists from 63 pediatric intensive care units (PICUs) were asked to provide the limits they considered acceptable for respiratory rate (RR), tidal volume (V(T)) and end-tidal CO(2) (PetCO(2)) during weaning from mechanical ventilation of a 3-month-old, a 2-year-old and a 10-year-old patient.

Setting: Pediatric intensivists working in Canada, France, Switzerland and Belgium.

Patients: None.

Interventions: None.

Results: Ninety-seven intensivists (43%) from 49 PICUs responded to the survey. The median minimal RR (25th;75th percentile) was: 20 breaths per minute (bpm) (15;25) for the 3-month-old, 15 bpm (10;15) for the 2-year-old and 10 bpm (10;15) for the 10-year-old patient. The median maximal RR was 50 bpm (40;60) for the 3-month-old, 40 bpm (30;40) for the 2-year-old and 30 bpm (30;40) for the 10-year-old child. The median minimal V(T) was 5 ml/kg (4;6) for the 3-month-old and 2-year-old patients and 5 ml/kg (5;6) for the 10-year-old. The median maximal PetCO(2) was 55 mmHg (50;60) for the 3-month-old, 50 mmHg (45;50) for the 2-year-old and 50 mmHg (50;55) for the 10-year-old.

Conclusion: This survey indicated that acceptable weaning limits are broad, as stated by the responders. We need to organize and consolidate our thinking on weaning children from mechanical ventilation before guidelines can be established.