A comparison of three methods that assess tracheal tube leakage: leak conductance, fractional volume loss, and audible assessment.

BACKGROUND: When intubating a child's trachea with an uncuffed tracheal tube (TT), it is current practice in anesthesia and intensive care to use the leak test to assess TT fit. The aim of this study is to compare three measures of assessing leak around uncuffed tracheal tubes in the PICU. METHODS: We obtained institutional ethical permission and written informed consent, prior to any clinical investigation, from the parents of 135 children who had surgery for cardiac defects. On admission to the PICU, we measured leak by audible assessment, fractional volume loss, and leak conductance for each patient. Measurements of fractional volume loss and leak conductance were repeated every 4 h thereafter until extubation. RESULTS: On admission to the PICU, calculated values of leak conductance were significantly different between each grade of audible leak (P < 0.001). Values of fractional volume loss were not significantly different between 'no leak' and 'small leak' grades of leak. Throughout the PICU stay, a significant correlation between mean leak conductance and mean fractional volume loss was found (0.86, 95% CI, 0.81-0.90). Significant agreement within time series of leak conductance and fractional volume recorded for each patient occurred in 47/128 cases (37%). CONCLUSIONS: On admission to the PICU, values of leak conductance are more strongly associated with audible assessment than with fractional volume loss. Throughout PICU stay, leak conductance is associated with fractional volume loss. This study demonstrates that leak conductance, calculated from routinely available pressure and flow signals, has the potential to represent the characteristics of the leak interface between a TT and the trachea.

Perioperative dexmedetomidine compared to midazolam in children undergoing open-heart surgery: A pilot randomised controlled trial.

Objective: There is a need for evidence on the best sedative agents in children undergoing open heart surgery for congenital heart disease. This study aimed to evaluate the feasibility and safety of dexmedetomidine in this group compared with midazolam. Design: Double blinded, pilot randomized controlled trial. Setting: Cardiac operating theatre and paediatric intensive care unit in Brisbane, Australia. Participants: Infants (≤12 months of age) undergoing their first surgical repair of a congenital heart defect. Interventions: Dexmedetomidine (up to 1.0mcg/kg/hr) versus midazolam (up to 80mcg/kg/hr), commenced in the cardiac operating theatre prior to surgery. Main outcome measures: The primary outcome was the time spent in light sedation (Sedation Behavior Scale [SBS] -1 to +1); Co-primary feasibility outcome was recruitment, retention and protocol adherence. Secondary outcomes were use of supplemental sedatives, ventilator free days, delirium, vasoactive drug support, and adverse events. Neurodevelopment and health-related quality of life (HRQoL) were assessed at 12 months post-surgery. Results: Sixty-six participants were recruited. The number of SBS scores in the light sedation range were greater in the dexmedetomidine group at 24 hours, 48 hours, and overall study duration (0-14 days) versus the midazolam group (24hr: 76/170 [45%] vs 60/178 [34%], aOR 4.14 [95% CI 0.48, 35.92]; 48hr: 154/298 [52%] vs 122/314 [39%], aOR 6.95 [95% CI 0.77, 63.13]; 0-14 days: 597/831 [72%] vs 527/939 [56%], aOR 3.93 [95% CI 0.62, 25.03]). Feasibility was established with no withdrawals or loss to follow-up at 14 days and minimal protocol deviations. There were no differences between the groups relating to clinical, safety, neurodevelopment or HRQoL outcomes. Conclusions: The use of dexmedetomidine was associated with more time spent in light sedation when compared with midazolam. The feasibility of conducting a blinded RCT of midazolam and dexmedetomidine in children undergoing open heart surgery was also established. The findings justify further investigation in a larger trial. Clinical trial registration: ACTRN12615001304527.

General anesthesia for children with severe heart failure.

Severe heart failure in children is uncommon. The anesthetic management of children with this condition is challenging. The authors aimed to identify the frequency with which anesthesia for short noncardiac surgical procedures or investigations was complicated by life-threatening hemodynamic instability and to describe the anesthetic techniques used. This study retrospectively reviewed the anesthetic charts and notes of children admitted acutely with a diagnosis of severe heart failure (fractional shortening of 15% or less) who received general anesthesia for noncardiac surgical or diagnostic interventions during the 3-year period from September 2005 to September 2008. In this study, 21 children received a total of 28 general anesthetics. Two patients (10%) experienced a cardiac arrest, and both required unplanned admission to the authors' pediatric intensive care unit (PICU) postoperatively. A variety of anesthetic techniques was used. In 27 (96%) of the 28 cases, perioperative inotropic support was required. General anesthesia for children with severe heart failure is associated with a significant complication rate and should be administered by anesthetists familiar with managing all aspects of circulatory support for children in an appropriate setting.

Ventricular septal defect closure in a child with osteogenesis imperfecta: risk factors and management.

Cardiac surgery in patients with osteogenesis imperfecta is challenging as the friability of the tissues can be hazardous before, during, and after the operation. A multidisciplinary approach with a planned strategy is essential for the successful management of these patients. We present a 6-year old child with osteogenesis imperfecta, who underwent ventricular septal defect closure without any complication.