Biomedical subjects

R H Ritz

Publications and source records attributed to R H Ritz.

6 recordsLinked to original sources

PubMed1999

Inhaled corticosteroids for asthma: are ED visits a missed opportunity for prevention?

Inhaled corticosteroids are effective but underused. This study evaluated the outpatient management of emergency department (ED) patients presenting with acute asthma and the relation of inhaled corticosteroid use to the patient's primary care provider (PCP) status. ED patients were interviewed by the hospital's asthma education program staff about their asthma. Overall, 85% (101 of 119) of asthmatics reported having a PCP. Although patients with a PCP and patients without a PCP both were using inhaled beta-agonists (93% v 89%, respectively; P = .54), patients without a PCP were less likely to be using inhaled corticosteroids (49% v 11%, P = .003). Controlling for age, acute asthma severity, and asthma hospitalizations during the past year, PCP status remained a significant predictor of inhaled corticosteroid use (odds ratio = 5.6; 95% confidence interval 1.1 to 27). Even among ED patients with a PCP, inhaled corticosteroids appear to be underused. ED asthma visits present an opportunity to initiate preventive measures such as inhaled corticosteroid use.

Acute Disease↗

PubMed1999

The effect of heliox on nebulizer function using a beta-agonist bronchodilator.

OBJECTIVE: To evaluate nebulizer performance when heliox was used to power the nebulizer. METHODS: Conventional and continuous nebulizer designs were evaluated. The conventional nebulizer was used with 5 mg albuterol and flows of 8 L/min air, 8 L/min heliox, and 11 L/min heliox; it was also used with 10 mg albuterol and a heliox flow of 8 L/min. The continuous nebulizer was set to deliver 10 mg of albuterol over 40 min at flows of 2 L/min air, 2 L/min heliox, and 3 L/min heliox; it was also used with 20 mg albuterol and a heliox flow of 2 L/min. A cotton plug at the nebulizer mouthpiece was used to trap aerosol during simulated spontaneous breathing. The amount of albuterol deposited on the cotton plug was determined spectrophotometrically. Particle size was determined using an 11-stage cascade impactor. RESULTS: For both nebulizer designs, particle size and inhaled mass of albuterol decreased significantly (p < 0.001) when the nebulizer was powered with heliox rather than air. When powered with heliox, the reduction in inhaled mass of albuterol was less for the conventional nebulizer (16%) than the continuous nebulizer (67%). The nebulization time, however, was more than twofold greater with heliox (p < 0.001). Increasing the flow of heliox increased the particle size (p < 0.05), inhaled mass of albuterol (p < 0.05), and inhaled mass of particles 1 to 5 microm (p < 0.05) to levels similar to powering the nebulizer with air at the lower flow. Increasing the albuterol concentration in the nebulizer and using the lower heliox flow increased the inhaled mass of albuterol (p < 0.05) while maintaining the smaller particle size produced with that flow. CONCLUSIONS: The use of heliox to power a nebulizer affects both the inhaled mass of medication and the size of the aerosol particles. The flow to power the nebulizer should be increased when heliox is used.

Adrenergic beta-Agonists↗

PubMed1999

Low-dose inhaled nitric oxide in acutely burned children with profound respiratory failure.

BACKGROUND: Inhaled nitric oxide (NO) is a rapidly acting selective pulmonary vasodilator that partially reverses the pathophysiology of acute respiratory distress syndrome (ARDS). METHODS: After human studies approval, we studied 11 burned children with severe ARDS in a trial of inhaled NO therapy, assessing its effect on intrapulmonary shunt as measured by the PaO2/FiO2 ratio (PFR). There were 12 episodes of administration; 1 child was treated twice. RESULTS: The children had an average age of 8.3 +/- 4.8 years (mean +/- SEM, range 11 months to 14 years) and average burn size of 64% +/- 22%. At the time of enrollment, the PFR averaged 95 +/- 50 and Murray lung score 3.1 +/- 0.5. Inhaled NO was begun an average of 6.3 +/- 5.5 days after injury and was administered for an average of 7.8 +/- 7.2 days at an average dose of 6.7 +/- 2.4 parts per million. PFR improved an average of 162% +/- 214%. Eight of the 11 children (73%) survived. The 3 nonsurvivors had similar admission PFR values (100 +/- 75 versus 93 +/- 44, P = .089) but a significantly less favorable initial response to inhaled NO, with a percentage of improvement in PFR at 1 hour after enrollment of 7.3% +/- 6.4% versus 213% +/- 226% (P = .026). There were no complications related to NO administration. CONCLUSIONS: Inhaled NO can be safely administered to treat ARDS in children with acute burns and appears to improve their ventilatory management. An immediate improvement in PFR with inhaled NO may correlate with survival.

Acute Disease↗

PubMed1997

Inhaled nitric oxide in burn patients with respiratory failure.

BACKGROUND: Inhaled nitric oxide (NO) has the potential to improve ventilation/perfusion matching and decrease pulmonary artery pressure in patients with profound respiratory failure. METHODS: Eight patients, average age of 35 years (range, 2.5-77 years) and burn size 49% (range, 19-80%), with inhalation injury and respiratory failure failing conventional management (average Pao2/FiO2 ratio (PFR) 85) were given inhaled NO at 20 ppm. RESULTS: An immediate mean increase in PFR of 10% and a decrease in pulmonary artery mean pressure of 7.8% was noted. At 24 hours, the average improvement in PFR was 28% and that in pulmonary artery mean pressure was 7.7%. Although not reaching statistical significance, these changes were more pronounced in those patients who went on to survive. There was no hypotension attributed to NO administration, and maximum methemoglobin levels averaged 0.9%. CONCLUSIONS: Inhaled NO can be safely administered to selected burn patients with severe respiratory failure who are perceived to be failing conventional support. Although current data are not adequate to support its general use, an immediate and sustained improvement in PFR and pulmonary artery mean pressure may correlate with eventual recovery of pulmonary function. Continued evaluation in controlled settings seems warranted and is in progress.

Administration, Inhalation↗

PubMed1991

Helium-oxygen mixture in the treatment of postextubation stridor in pediatric trauma patients.

OBJECTIVE: To assess the effectiveness of a helium-oxygen mixture in reducing post-extubation stridor in children hospitalized for burns or trauma. DESIGN: Randomized, controlled crossover trial. SETTING: Harborview Medical Center's Burn and Trauma ICUs from March to September 1989. PATIENTS: Children less than 15 yr old who were electively extubated and had symptoms of postextubation stridor, but required less than or equal to 35% oxygen. INTERVENTION: Each treatment (helium-oxygen and oxygen-supplemented room air) was given in random order for 15 min after extubation. MEASUREMENTS: Respiratory distress was assessed by a physician blinded to treatment order using a standard stridor score and clinical judgment. RESULTS: There were 13 children with 15 extubations; seven (47%) of 15 patients required subsequent treatment with racemic epinephrine or reintubation. Stridor scores were lower with helium-oxygen than with oxygen-supplemented room air (2.8 vs. 3.7, p less than .005), and helium-oxygen was preferred in eight of nine trials in which one treatment was clearly favored by the physician. CONCLUSION: Because helium-oxygen therapy can reduce stridor scores and is clinically preferred by physicians caring for stridorous children, it may be a useful adjunctive therapy in pediatric trauma patients with postextubation stridor.

Adolescent↗

PubMed1989

Continuous in-line nebulizers complicate pressure support ventilation.

Patients ventilated in the pressure support mode must generate a negative airway pressure before the ventilator will deliver a breath. Inserting a continuous-flow nebulizer between the patient and the sensor in the ventilator makes it more difficult for the patient to generate this negative pressure. We observed two mechanically ventilated patients who were unable to initiate ventilator breaths in the pressure support mode while bronchodilators were being administered through a continuous-flow nebulizer. In neither case did ventilator alarms sound. Using a lung model, we found that when the nebulizer flow rate exceeded the mean inspiratory flow rate of the test lung, the negative pressure necessary to trigger the pressure support ventilator could not be generated. Critical care providers need to be aware of this potential complication, since it may lead to serious underventilation of their patients.

Administration, Inhalation↗