Non Invasive Positive Pressure Ventilation in Status Asthmaticus

Asthma is a common, chronic and complex disorder of the airways, with symptoms that are
variable and recurring. It is characterized by bronchial hyperresponsiveness to various
stimuli, airflow obstruction that is often reversible, and underlying inflammation.
Conventional therapy for status asthmaticus is directed at relieving bronchoconstriction,
decreasing airway inflammation and clearing airway mucus. However, in some patients, maximal
standard therapies are inadequate and can lead to prolonged hospitalization. Intubation and
mechanical ventilation in patients with asthma is associated with significant risks. NPPV
has several advantages over invasive intubation and mechanical ventilation. It leaves the
upper airway intact, and avoids the risks associated with endotracheal intubation including
upper airway trauma, laryngeal swelling, postextubation vocal cord dysfunction, and
nosocomial infections.

This study will be a prospective, open-labeled, randomized clinical trial comparing the use
of NPPV plus standard of care versus standard of care alone in children admitted for status
asthmaticus. A simple random numbers table will be used to assign subjects to either the
NPPV plus standard of care group or standard of care alone group. In the first hour, all
patients in both groups will receive a 2mg/kg dose of systemic steroid, continuous albuterol
at 0.5mg/kg/hr (max of 15mg/hr) with 3 doses of 0.25-0.5 mg nebulized iprotropium bromide,
and supplemental oxygen keep saturation >92%. Patients on both therapeutic arms will
continue to receive 2mg/kg dose of systemic steroid per day, continuous albuterol at
0.5mg/kg/hr (max of 15mg/hr) and supplemental oxygen to keep saturation >92%.

Patients randomized to the NPPV plus standard of care group will be fitted with a nasal or
face mask and placed on the Respironics V60 BiPAP Ventilator 33. Masks with gel seals at
different pressure points will be used to prevent skin breakdown. To optimize patient
cooperation, the mask will initially be applied manually to the patient's face. After a
short adaptation period for the patient to feel comfortable, the mask will be firmly applied
with head straps to minimize air leak without causing skin injury. Pressures will initially
be low for comfort and acceptance while being placed on the machine.

Patients randomized to the standard of care group will be placed on a similar continuous
nebulizer attached to a similar oxygen blender as the ones used with the V60 unit set-up,
using the same liter flow (11 liters per minute). An aerosol mask will be placed on the
patient to aid in the delivery of the medication. The oxygen will be analyzed at the site of
this mask with the initial set-up and any time the oxygen is decreased or increased.

Data will be collected at baseline as soon as the patient is enrolled in the study. It will
include: demographic variables, medical record number, age, race, gender; history and
physical findings, other medical conditions, vital signs, oxygen saturation at baseline,
clinical asthma score (CAS), peak flow in children >6 years of age, asthma severity prior to
admission, NPPV settings, length of stay in the PICU, side effect profiles (tremor,
tachycardia, agitation, nausea, nasal bridge pain, skin irritation/ulceration, gastric
distension, dry eyes/mucosal dryness, sinus/ear pain, aspiration pneumonia, hypotension and
pneumothorax).

Each child's participation in the study will end when the child is transferred from the
PICU.

Inclusion Criteria:

- 1-18 years old

- Known H/O asthma

- With status asthmaticus

- CAS score 2-8 after one dose of systemic steroid, 1 hour of continuous albuterol and
3 doses of ipratropium bromide.

Exclusion Criteria:

- No previous history of asthma.

- Absence of airway protective reflexes.

- Absence of respiratory drive.

- Problems with clearing oral secretions.

- Need for emergent intubation as determined by the attending physician.

- Facial or airway anomaly or injury precluding the use of tight fitting mask.

- Discretion of the attending physician depending on the severity of illness