Cuffed vs. uncuffed tracheal tubes in children: a randomised controlled trial comparing leak, tidal volume and complications.

Cuffed tracheal tubes are increasingly used in paediatric anaesthetic practice. This study compared tidal volume and leakage around cuffed and uncuffed tracheal tubes in children who required standardised mechanical ventilation of their lungs in the operating theatre. Children (0-16 years) undergoing elective surgery requiring tracheal intubation were randomly assigned to receive either a cuffed or an uncuffed tracheal tube. Assessments were made at five different time-points: during volume-controlled ventilation 6 ml.kg-1 , PEEP 5 cmH2 O and during pressure-controlled ventilation 10 cmH2 O / PEEP 5 cmH2 O. The pressure-controlled ventilation measurement time-points were: just before a standardised recruitment manoeuvre; just after recruitment manoeuvre; 10 min; and 30 min after the recruitment manoeuvre. Problems and complications were recorded. During volume-controlled ventilation, leakage was significantly less with cuffed tracheal tubes than with uncuffed tracheal tubes; in ml.kg-1 , median (IQR [range]) 0.20 (0.13-0.39 [0.04-0.60]) vs. 0.82 (0.58-1.38 [0.24-4.85]), respectively, p < 0.001. With pressure-controlled ventilation, leakage was less with cuffed tracheal tubes and stayed unchanged over a 30-min period, whereas with uncuffed tracheal tubes, leakage was higher and increased further over the 30-min period. Tidal volumes were higher in the cuffed group and increased over time, but in the uncuffed group were lower and decreased over time. Both groups showed an increase in tidal volumes following recruitment manoeuvres. There were more short-term complications with uncuffed tracheal tubes, but no major complications were recorded in either group at long-term follow-up. With standardised ventilator settings, cuffed tracheal tubes produced better ventilation characteristics compared with uncuffed tracheal tubes during general anaesthesia for routine elective surgery.

The use of 'pericardial hoods' for maintaining exact coronary artery geometry in the arterial switch operation with complex coronary anatomy.

OBJECTIVE: Complex coronary artery anatomy is the major risk factor for the arterial switch operation. Of the many approaches described the 'trap door' technique for coronary reimplantation is most flexible and allows safer transfer in complex arterial configurations. However, we have occasionally been concerned regarding torsion of the vessels with this approach. We therefore explored the role of trap-door augmentation with pericardial hoods to maintain exact coronary geometry during coronary transfer. METHODS: Between February 1992 and December 1997, 80 patients underwent an arterial switch procedure at our institution. Sixty-seven patients underwent direct coronary reimplantation. In ten, coronary/great vessel anatomy was considered unfavourable and the trap-door approach was adopted primarily. In two an augmented trap-door was performed as the primary procedure and in the last patient Aubert's approach was used. In five patients during rewarming, ischaemic changes were noted on the electrocardiogram and/or regional wall motion abnormalities on transoesophageal echocardiography. This prompted revision of the appropriate coronary anastomosis. In three it was considered the anastomosis was kinked due to angulation of the button; in two the coronary was overstretched. In four, revision of the anastomosis was by pericardial hood augmentation. RESULTS: In all patients there was normalization of the electrocardiogram and immediate improvement in cardiac function documented by transoesophageal echocardiography. No early or late death occurred in the pericardial hood group nor were there any readmissions for any reason. CONCLUSIONS: Pericardial augmentation of trap-door aortic anastomoses allows for the maintenance of exact coronary artery geometry during the arterial switch procedure and minimizes the risk of myocardial ischaemia. We believe it broadens the application of the arterial switch procedure to even the most complex coronary anatomy and is a useful adjunct to the other techniques of coronary transfer.