| Popis: |
Introduction: We developed an endotracheal tube (ETT) equippedwith 2 polyvinylchloride (PVC) cuffs and a supplementary canalin-between cuffs through which a continuous positive pressure of5 cmH2O is provided (PVCdc).Methods: We compared the PVCdc with 4 different cuff types[cylindrical PVC, PVCcyl); conical PVC, (PVCcon); cylindrical polyurethane(PU), (PUcyl); and conical PU, (PUcon)]. ETTs were placedin an artificial trachea. Cuffs were kept inflated at 25 cmH2O.Three mL dyed water was placed above the cuff and leakagerecorded under static and dynamic (i.e. 5 cmH2O PEEP alone andpositive pressure ventilation plus 5cmH2O PEEP) conditions. Atthe end of the dynamic experiments, either PEEP was zeroed orthe ETTs disconnected.Results: In the static model, leakage flows were 10.8 5.0;1.6 1.4; 0.04 0.03; 0.06 0.07; and 0.0 0.0 ml/min for respectivelythe PVCcyl, PVCcon, PUcyl, PUcon and PVCdc cuff (P < 0.001,PVCdc vs. other cuffs). In the dynamic setting, no leakage wasdetected up to 60 min in any of the studied cuffs. Loss of PEEP andETT disconnection resulted in immediate dye inflow alongside allcuffs except for the PVCdc (P < 0.001, PVCdc vs. other cuffs).Conclusions: In static conditions, the novel PVCdc outperformedall PVC and PU-cuffed comparator ETTs in preventing leakage.PEEP guaranteed adequate sealing in all studied ETTs. However,only the PVCdc protected against leakage after release of PEEP orETT disconnection. |
