2003 OPEN FORUM Abstracts
THE UTILIZATION OF BLOOD GAS AND CHEST RADIOGRAPHY (CXR) RESULTS VS PHYSICAL ASSESSMENT IN DETERMINING PLACEMENT ON CONTINUOUS POSITIVE AIRWAY PRESSURE (CPAP) IN THE TREATMENT OF BRONCHIOLITIS PATIENTS.
Kim Bennion BS RRT, Julie Ballard BS RRT and Glenna McKinley BS RRT. Respiratory Care Services, Primary Children's Medical Center, Salt Lake City, Utah.
Introduction: Our hospital has a multi-disciplinary assessment team that specializes in the care of bronchiolitis patients (pts). Specially trained respiratory therapists daily assess all pts ordered on respiratory care interventions. The team has employed a bronchiolitis score (BS) to assess pt response to various interventions for the past 6 years. The BS is based on respiratory rate, breath sounds and retractions with each of these being scored on 4 levels (0-3). The cumulative score in all 3 areas define respiratory distress as: 0-1 normal, 2-3 mild, 4-6 moderate and 7-9 severe. An improvement in respiratory distress is defined as a BS decrease > 1 after intervention. Previous to 2002, pts requiring non-invasive CPAP were admitted to our pediatric intensive care unit (PICU). It was felt that early intervention with CPAP on the floors (as PICU beds were unavailable) would decrease PICU admits and the need for more invasive forms of ventilation. At the same time, CPAP would provide relief for respiratory distress that was largely due to encroaching atelectasis. Many physicians felt that a CO2 > 55 and/or chest radiography (CXR) would be the best indicators for placement on CPAP. Other caregivers argued that a thorough physical assessment utilizing the BS would be a better indicator since many pts who appeared to be in profound respiratory distress (respiratory rates >65, retractions in > 2 locations and markedly decreased or absent lower lung breath sounds) often had acceptable upper limit CO2 values as defined by our physicians (46-54 mmHg). Our overall goal with CPAP was to provide early intervention in an attempt to improve atelectasis before marked alveolar collapse ensued which often required transfer to PICU and invasive ventilation. We defined BS criteria for CPAP placement as a score > 6 with increasing oxygen demands.
Methods: Data on blood gases, CXR results and scores from Nov 2002-April 2003 were extracted from our data systems. Inclusion criteria were: (1) primary diagnosis of bronchiolitis, (2) < 24 months of age, (3) BS > 6, and (4) received a blood gas & CXR prior to CPAP placement. We sought to determine the best indicator(s) for CPAP placement.
RESULTS: Thirty-six pts met the initial criteria with 18 excluded due to no CXR and/or no CBG leaving us 18 pts to study. We report that only 5 (28%) of pts had a CO2 > 55 mmHg. CXR results are reported in Table 1.
|Table 1: CXR Result||# (%)|
|Focal infiltrate(s)||1 (6)|
|Consistent with Bronchiolitis (general opacification)||8 (44)|
|Viral interstitial disease (pneumonia)||2 (11)|
CONCLUSION: It has been our observation that many bronchiolitis pts maintain minute ventilation by increasing respiratory rate at the expense of a diminishing tidal volume. This, coupled with airway inflammation & mucus plugging which are common in bronchiolitis, lead to atelectasis with marked respiratory distress and impending failure if not treated early. We suggest that early intervention with non-invasive CPAP decreases respiratory distress in many bronchiolitis pts. CXR and CBG results do not appear to be superior methods for determining severity of respiratory distress or as useful in determining CPAP placement when compared to a thorough physical assessment.