BI-LEVELPOSITIVEAIRWAYPRESSURE(BIPAP)
■ It is a combination of CPAP and inspiratory assist.
■ Inspiratory positive pressure (8–10cm H 2 O) exceeds that of expiratory
positive pressure (3–5cm H 2 O) provided.
■ It provides extrinsic PEEP.
■ Each cycle is triggered by patient initiation of inhalation.
COMPLICATIONS
■ Volutrauma, pressure necrosis of the skin from an ill-fitting mask, gastric
distention, delayed definitive airway management.
A 60-year-old smoker in COPD exacerbation is failing aggressive noninva-
sive therapy. He is now orotracheally intubated. What should his initial
ventilator settings be?
In a patient with COPD, the initial selected tidal volume and rate should be
slightly reduced to avoid hyperinflation and hyperventilation. Begin with 10 mL/kg
of patient’s ideal body weight at 10 breaths per minute and 100% FiO 2 and
wean as tolerated.
MECHANICALVENTILATION
Initial ventilator setting should be based on review of the underlying pulmonary
process (see Table 1.6).
COMPLICATIONS
■ Volutrauma
■ Overdistention of alveoli
■ Prevented by using smaller tidal volumes
RESUSCITATION
BiPAP is a combination of
CPAP and inspiratory assist.
TABLE 1.6. Initial Ventilator Settings
PULMONARYPROCESS VENTILATORSETTINGS
Pulmonary contusion Low tidal volume (5–10 mL/kg) to prevent barotrauma
PEEP of 5–15 cm H 2 O to prevent alveoli collapse
Asthma/COPD Slow respiratory rate and prolonged exhalation phase PEEP
ARDS Low respiratory rate (maximize recruitment)
Low tidal volume (6 mL/kg) to prevent volutrauma
PEEP
Neonates Best setting = pressure controlled ventilation
Acidosis Continue respiratory compensation with a high respiratory rate
Head injury Avoid hypercapnea, which causes cerebral vasodilation and ↑ICP.