Pediatric emergency medicine trisk 2768 2768

4. Muscle relaxants for intubated patients—rocuronium 1–
1.2 mg/kg/dose or vecuronium bromide, starting at 0.1
mg/kg every 1–2 hrs or alternative 0.1–0.2 mg/kg/hr
drip
PEEP, positive end-expiratory pressure; CPAP, constant positive airway pressure; BiPAP, bilevel positive
airway pressure.

Specific ventilation strategies will vary based on underlying disease. In
children with acute respiratory failure but normal lung function (e.g., CNS
depression), standard airway pressures, and respiratory rates are appropriate.
Positive end-expiratory pressures (PEEPs) may be useful where alveolar
recruitment is important to improve gas exchange (e.g., atelectasis). This can be
done manually with a bag and mask, or with CPAP or BiPAP. PEEP shifts lungs
to a position on the pressure–volume curve that improves alveolar ventilation by
increasing the end-expiratory lung volume and functional residual capacity. Any
ventilation strategy must aim to minimize the risk of volutrauma and barotrauma.
In patients with decreased lung compliance due to either stiff lungs (e.g., fibrosis)
or hyperinflation (e.g., bronchiolitis or asthma), higher pressures must be used to
sufficiently ventilate the child. The inspiratory:expiratory (I:E) ratio can also be
tailored to the disease process. An increased I:E ratio is used in obstructive lower
airway disease to extend exhalation time to better allow elimination of CO2 .
Increased I:E ratios (generally greater than 1:3) are frequently required.
Permissive hypercapnia, accepting elevated PCO2 values as long as pH is
maintained (e.g., ≥7.2), may be advantageous, as this may allow for lower peak
pressures during ventilation, which will reduce the risk of barotrauma.
Fluid management is another important component of care for patients with
respiratory failure. In general, fluids should be titrated to maintain normal
intravascular volume as determined by monitoring heart rate, blood pressure,
peripheral perfusion, and urine output. However, patients with significantly
increased work of breathing generate high negative intrathoracic pressure which
increases venous return. When these patients transition to positive-pressure

ventilation, venous return rapidly decreases and may precipitate cardiovascular
collapse. Therefore, unless clinical circumstances mandate more immediate
action, rapid intravascular repletion before initiating positive pressure (through
noninvasive ventilation or intubation) is prudent. In contrast, for patients with
interstitial disease or pulmonary capillary leak, a slightly reduced intravascular
volume may improve the cardiopulmonary mechanics necessary for effective
ventilation. As a result, the FiO2 requirement may be decreased and airway