PubMed Health⌕ Search

Biomedical subjects

Howard B Panitch

Publications and source records attributed to Howard B Panitch.

6 recordsLinked to original sources

Infant pulmonary function testing.

Pulmonary function tests in infants have been used for many years, but they have been largely relegated to specialized centers and research purposes. More recently, development of commercial equipment and newer techniques has allowed for more broad use and application of these tests. This review describes different techniques that have been used to study infants and toddlers, and their clinical applications.

Child, Preschool↗

Respiratory syncytial virus bronchiolitis: supportive care and therapies designed to overcome airway obstruction.

Treatment of respiratory syncytial virus bronchiolitis rests primarily on supportive care with oxygen and fluid management. Other therapies commonly used include bronchodilators, corticosteroids and ribavirin, when considered appropriate. Small studies have also suggested that exogenous surfactant, helium/oxygen mixtures (heliox) and combination therapies may offer clinical benefit as well. Management of bronchiolitis can be facilitated by (1) recognizing the risks and benefits of various therapies, (2) understanding the markers of disease severity and (3) gaining familiarity with the time course of viral replication compared with presentation of symptoms. Although oxygen administration and judicious fluid replacement are the only interventions proved to be of reliable benefit to infants with bronchiolitis, newer studies support a role for adjunctive therapies aimed at relieving airway obstruction, especially when administered very early in the course of the illness or given to infants with more severe disease.

Airway Obstruction↗

Noninvasive measurement of the tension-time index in children with neuromuscular disease.

Respiratory muscle weakness is common in children with neuromuscular disease (NMD). We hypothesized that weakness puts them at risk for respiratory muscle fatigue, a harbinger of chronic respiratory failure. We therefore measured a noninvasive index of respiratory muscle fatigue, the tension-time index of the respiratory muscles (TT(mus)), in 11 children with NMD and 13 control subjects. Spirometric flow rates and maximal inspiratory pressure were significantly lower in the NMD group than in controls (43 +/- 23 vs. 99 +/- 21 cmH2O, P < 0.001). The mean TT(mus) was significantly higher in the NMD group than in controls (0.205 +/- 0.117 vs. 0.054 +/- 0.021, P < 0.001). The increase in TT(mus) was primarily due to an increase in the ratio of average mean inspiratory pressure to maximal inspiratory pressure, indicating decreased respiratory muscle strength reserve. We found a significant correlation between TT(mus) and the residual volume-to-total lung capacity ratio (r = 0.504, P = 0.03) and a negative correlation between TT(mus) and forced expiratory volume in 1 s (r = -0.704, P < 0.001). In conclusion, children with NMD are prone to respiratory muscle fatigue. TT(mus) may be useful in assessing tolerance during weaning from mechanical ventilation, identifying impending respiratory failure, and aiding in the decision to institute therapies.

Adolescent↗

Pulmonary function in technology-dependent children 2 years and older with bronchopulmonary dysplasia.

Somatic and pulmonary growth coincide with resolution of hypoxemia by 2 years of age in most children with bronchopulmonary dysplasia (BPD). However, a distinct subgroup of children with BPD continue to require mechanical ventilation and/or supplemental oxygen beyond 2 years of age. This study tested the hypothesis that indices of pulmonary function would be significantly worse in children with BPD 2 years and older who remained technology-dependent secondary to hypoxemia, compared to those of age-matched children with BPD who were normoxemic. We measured pulmonary mechanics in 21 oxygen- or ventilator-dependent children with BPD 2 years and older (BPDO2 group; mean age+/-SD, 30.2+/-6.5 months) and in 19 children with BPD who had been weaned off mechanical ventilation and supplemental oxygen for at least 6 months (control group; mean age, 30.1+/-5.5 months). Respiratory rate and tidal volume were measured after sedation with chloral hydrate, and dynamic compliance and expiratory conductance were calculated using the esophageal catheter technique. Maximal flow at FRC (V'(maxFRC)) and ratio of forced-to-tidal flows at midtidal volume were obtained by the rapid thoracic compression technique. FRC was determined by nitrogen washout. There were no statistically significant differences in most measured indices of pulmonary mechanics between the BPDO2 and control groups. However, V'(maxFRC)/FRC was higher in controls compared to subjects in the BPDO2 group (0.81+/-0.40 sec(-1) vs. 0.34+/-0.21 sec(-1), P<0.003). We conclude that most indices of pulmonary function in children with BPD 2 years and older do not reflect the need for mechanical ventilation or supplemental oxygen. We speculate that measurements of lung elastic recoil and tests of distribution of ventilation and pulmonary perfusion may be more sensitive in differentiating normoxemic and hypoxemic children with BPD 2 years and older.

Bronchopulmonary Dysplasia↗

Transtracheal oxygen catheters in a pediatric population.

This is the first report to evaluate transtracheal oxygen catheter (TTOC) use in a pediatric patient series. Seven pediatric patients (4 boys and 3 girls) received TTOCs in 2 tertiary care medical centers. The medical indications included bronchopulmonary dysplasia in 4 patients and tracheomalacia in the other 3. The average age at the time of placement was 22 months (range, 2 weeks to 37 months). Catheter placement for 4 patients was through an open tracheotomy stoma. In 3, placement was through a percutaneous technique. The follow-up ranged from 2 weeks to 5 years. There were no long-term complications. Transient needs for supplemental oxygen were all met by the TTOC system. In 4 patients, the catheter has been removed because of resolution of the supplemental oxygen requirements. Minor complications included skin site infection and mucus plugging. In 1 patient, accidental dislodging of the catheter led to its replacement in the operating room. In 1 percutaneous placement, a pneumothorax occurred and resolved without any persistent morbidity. We conclude that transtracheal oxygen delivery can be a reasonable alternative to a nasal cannula or formal tracheotomy in selected pediatric patients in whom long-term oxygen delivery, but not an alternate airway, is required. In order to avoid complications, meticulous technique must be adhered to in using the percutaneous approach for placement.

Age Factors↗