We studied patient's age, sex, APACHE II score, cause of intubation/mechanical ventilation, duration of ventilatory support, maximum inspiratory pressure (MIP; mmHg), maximum expiratory pressure (MEP; mmHg) and respiratory shallow breathing index (RSBI; l), rate of extubation success and ratio of reintubation.
The decision to provide mechanical ventilatory support should be based on a pattern of progressively increasing rate of breathing with falling tidal volumes (rapid-shallow breathing) and respiratory distress.
The rapid shallow breathing index (RSBI) (respiratory rate (RR) over tidal volume (VT) ratio) recorded during a T-piece spontaneous breathing trial (SBT) is known as the most reliable physiologic predictor.
We calculated the indices proposed by the TF (spontaneous respiratory rate, paediatric rapid shallow breathing, rapid shallow breathing occlusion pressure [ROP] and maximal inspiratory pressure during an occlusion test [Pimax]) and weaning endurance indices (pressure-time index, tension-time index obtained from P0.1 [TTI1] and from airway pressure [TTI2]) during spontaneous breathing.
Adjustment of rapid shallow breathing may lead to respiratory muscles fatigue.
A variety of criteria have been proposed as predictors of the success or failure of weaning attempts, among them rapid shallow breathing – the ratio of respiratory frequency to tidal volume (f/Vt).
Variables analyzed were: age, APACHE score, length of stay in the ICU (LOS), and cardiorespiratory variables including respiratory rate, rapid shallow breathing index (f/VT), maximum inspiratory (PImax) and expiratory (PEmax) pressure.
If the patient is not able to hold his or her breath, CT could be performed with a free-breathing technique but the patient should be advised to perform calm, shallow breathing and to avoid excessive respiratory excursions.
LR+, positive likelihood ratio; LR-, negative likelihood ratio; Pimax, maximal inspiratory pressure dring an occlusion test; ROP, rapid shallow breathing occlusion pressure; RRs, spontaneous respiratory rate; RSBp, paediatric rapid shallow breathing; TF, Task Force of the American College of Chest Physicians.
During spontaneous ventilation in the T piece, in the 1 st and 30th min measurements of tidal volume (VT), minute ventilation (Ve), respiratory rate (f), rapid shallow breathing index (f/VT), heart rate and peripheral oxygen saturation were taken.
