Bronchodilator Delivery Research Articles

Bronchodilator delivery with metered-dose inhalers in mechanically-ventilated patients.

Metered-dose inhalers (MDIs) provide several advantages over nebulizers, including ease of administration, decreased cost, reliability of dosing, and freedom from contamination. However, this method of aerosol delivery has been considered ineffective in mechanically-ventilated patients because most of the aerosol deposits in the endotracheal tube and ventilator circuit. A smaller amount of aerosol from a MDI is deposited in the lower respiratory tract of mechanically-ventilated patients than in ambulatory patients, although recent studies show that a significant bronchodilator effect can still be achieved. When employed optimally, significant bronchodilation occurs with as little as 4 puffs of a sympathomimetic aerosol. Multiple factors influence the efficacy of MDIs in mechanically-ventilated patients. The method of connecting the MDI canister to the ventilator circuit has a marked effect on aerosol delivery, and other factors include the timing of MDI actuation, ventilator mode, tidal volume, circuit humidity, and duty cycle. With a proper technique of administration, a MDI serves as an effective, convenient, and safe method for delivering bronchodilator aerosols in mechanically-ventilated patients.

The Chocuhaler: sweet deliverance in asthma management.

To determine the characteristics of a new cocoa-based edible spacer device for the delivery of aerosol bronchodilator. In-vitro comparison of two spacer devices (standard and edible) and determination of bronchodilator response using the edible spacer. A university children's hospital in Western Australia. Two volunteers with moderate asthma. Compared with a standard spacer, the edible spacer delivered significantly more bronchodilator in droplets of a size likely to enter the respiratory tract. A significant bronchodilator response occurred in two out of two subjects when salbutamol was inhaled orally via the chocolate spacer. No significant bronchodilator response occurred in either subject when the spacer was eaten at the end of the study. The chocolate spacer used in this study is a suitable device to deliver salbutamol by inhalation. However, there may be potential drawbacks of weight gain in some patients and meltdown in hot climates.

Bronchodilator delivery by metered-dose inhaler in ventilator-supported patients.

The optimal dose and technique for administration of bronchodilators with a metered-dose inhaler (MDI) in mechanically ventilated patients have not been established. We studied the efficacy and safety of 10 puffs (90 micrograms/puff) of albuterol administered by an MDI in seven mechanically ventilated patients with chronic obstructive pulmonary disease (COPD). Rapid airway occlusions at constant flow inflation were performed before and at 5-min intervals after administration of albuterol for 60 min. Significant decreases in maximum (Rrsmax; p < 0.01) and minimum inspiratory resistance (Rrsmin; p < 0.01) were present at 5 min and persisted for 60 min after administration of albuterol (p < 0.01 for both parameters). Rrsmax indicates maximal inspiratory resistance while Rrsmin represents the ohmic flow resistance. Intrinsic positive end-expiratory pressure decreased significantly (p < 0.05) 15 min after albuterol administration. Heart rate, blood pressure, and arterial oxygenation did not show significant change after albuterol. In summary, 10 puffs of albuterol given by an MDI and spacer produced significant bronchodilation in ventilator-supported patients with COPD, without producing side effects. In conclusion, higher doses of albuterol given by an MDI and spacer could be used routinely in mechanically ventilated patients with COPD.

Evaluation of a Reservoir Device for Metered-Dose Bronchodilator Delivery to Intubated Adults: An in Vitro Study

We investigated the use of a reservoir device for delivery of a MDI bronchodilator aerosol using a lung model of an intubated, mechanically ventilated adult. Albuterol (Proventil) was delivered with a MDI using three methods. In method 1, the MDI was attached directly onto the ETT using a commercially available actuator/adapter. In method 2, the Monaghan AeroVent reservoir was placed on the inspiratory limb of the ventilator circuit just before the patient Y connector. In method 3, the AeroVent was placed between the patient Y connector and the ETT. Standardized ventilator settings with a Servo 900C were used for all three methods (VE = 9.6 L; respiratory rate = 12 breaths per minute; TI = 20 percent of 1 s). Aerosol drug delivery was measured at the distal tip of the ETT using a spectrophotometric technique. Percentage of amount delivered was calculated from measured delivery of the MDI. The MDI directly on the ETT delivered 7.3 percent of the total dose to the end of the ETT. The AeroVent on the inspiratory limb increased this to 32.1 percent and the AeroVent between the Y connector and the ETT delivered 29 percent. Both reservoir delivery methods delivered significantly more drug than direct placement of the MDI on the ETT (p less than 0.01) but did not differ from each other (p greater than 0.05). Use of the AeroVent reservoir chamber significantly increased bronchodilator delivery by aerosol with an MDI in an adult lung model of an intubated patient on ventilatory support.

Aerosol Bronchodilator Delivery during Mechanical Ventilation: Nebulizer or Inhaler?

1991;100;1103-1104 Chest D Hess mechanical ventilation. Nebulizer or inhaler? Aerosol bronchodilator delivery during http://chestjournal.chestpubs.org/content/100/4/1103.citation can be found online on the World Wide Web at: The online version of this article, along with updated information and services ) ISSN:0012-3692 http://chestjournal.chestpubs.org/site/misc/reprints.xhtml ( without the prior written permission of the copyright holder. reserved. No part of this article or PDF may be reproduced or distributed Chest Physicians, 3300 Dundee Road, Northbrook, IL 60062. All rights of been published monthly since 1935. Copyright1991by the American College is the official journal of the American College of Chest Physicians. It has Chest

Metered dose inhalers for bronchodilator delivery in intubated, mechanically ventilated patients: Gay P, Patel H, Nelson S, et al Chest 99: 66–71 Jan 1991

Metered dose inhalers for bronchodilator delivery in intubated, mechanically ventilated patients: Gay P, Patel H, Nelson S, et al Chest 99: 66–71 Jan 1991

The adult patient’s difficulties with inhalers

Fifty percent or less of adult patients can be expected to be able to use the conventional metered dose inhaler (MDI) efficiently if the only tuition they receive is the manufacturer's instruction pamphlet and a high proportion of patients should be expected to develop a poor inhalation technique unless their ability to use an MDI is checked regularly. Because of these problems I believe that the future of the conventional MDI is limited. The new generation of inhalation devices have exciting design features and are undoubtedly better than established inhalation systems in that they are as effective and much easier to use. When these new devices are all available for the delivery of bronchodilators and corticosteroids there is no doubt that many patients will benefit. They should be prescribed in preference to the MDI for all patients whose ability to use a conventional pressurized inhaler is not routinely assessed prior to the institution of therapy and at regular intervals thereafter.

Nebulizer vs Spacer for Bronchodilator Delivery in Patients Hospitalized for Acute Exacerbations of COPD

This double-blind crossover study compared the efficacy of two methods of delivery (MDI-spacer and nebulizer) of inhaled albuterol to patients hospitalized for an acute exacerbation of COPD. Within 24 h of admission, 20 subjects (mean age, 69 years) with severe airflow obstruction (mean FEV, 0.69 L) were subjected to a treatment with an MDI-spacer (0.36 mg of albuterol or placebo) followed by treatment with a nebulizer (2.5 mg of albuterol or placebo). Active drug was given by only one device (randomly assigned in a double-blind manner), and the entire sequence was repeated in 4 h, with active drug given in the alternate device. Spirometric data and the Borg dyspnea score were obtained before and 1 h after each sequence of treatments. Treatment resulted in significant improvements in the FEV1, FVC, and Borg score. The percent improvement in the FEV1 was slightly larger after treatment with the nebulizer (16.7 percent vs 13.4 percent). Improvements in the Borg score were slightly larger after treatment with the MDI-spacer (-1.08 vs -0.73). However, these differences were not statistically significant. This study suggests that the MDI-spacer system is an effective method of sympathomimetic delivery in this setting, provided patients are able to master the technique.

Experience with a metered-dose inhaler with a spacer in the pediatric emergency department.

Studies of adults suggest that metered-dose inhalers with spacers are as effective as hand-held nebulizers for bronchodilator delivery. We studied 13 children with acute asthma. They received two puffs every 2 minutes from metered-dose inhalers with spacers (range, 4 to 14 puffs) titrated until improvement stopped. Peak expiratory flow increased 34% for metered-dose inhalers with spacers after the first 2 puffs and increased 87% for metered-dose inhalers with spacers after dose titration. After titration, respiratory rate decreased by 12%, heart rate increased by 2%, and breath sounds improved in 92% of the patients. We concluded that the metered-dose inhalers with spacers are an effective device for the treatment of asthma in the pediatric emergency department and that the use of metered-dose inhalers with spacers with titration can achieve significant bronchodilation in the treatment of patients with acute asthma.

Cost-Benefit Comparison of Aerosol Bronchodilator Delivery Methods in Hospitalized Patients

We compared two modes of aerosol bronchodilator delivery in 34 patients hospitalized with obstructive airways diseases. The standard mode, therapist-administered up-draft nebulization (UDN), is labor-intensive and therefore relatively costly. The alternative mode, self-administration by a metered dose inhaler (MDI), is less costly, but its efficacy over an entire hospitalization has heretofore not been established. Patients were enrolled after transfer to the pulmonary ward from the emergency room or intensive care units (ICU). We then randomized them to receive metaproterenol q4h either via MDI or UDN. Daily spirometry revealed that MDI and UDN were associated with equivalent bronchodilation initially and equivalent improvement at discharge. The duration of hospitalization for the two groups was also the same. Thus, the two delivery methods were equally effective. We could not attribute this equivalence to pretreatment intergroup differences or to differences in concomitant therapy with steroids, theophylline, other bronchodilators, or antibiotics. Routine use of MDI rather than UDN in all non-ICU adult patients would save $253,487 per year at our institution alone.

Two Methods of Administering Nebulized Salbutamol

Wood, D. O., Chandler, Dianne and Dugdale, A. E. (1978). Aust. Paediatr. J., 14, 150–153. Two methods of administering nebulized salbutamol. A controlled study. A cross‐over study has been designed to test the efficiencies of two methods of delivering a continuous aerosol of salbutamol to children with acute wheezing and respiratory distress. The methods used were the conventional face mask and a wide bore tube which the child held In his mouth. Statistical analysis of the change in lung function tests following the two methods of administration showed no significant differences in effectiveness. A child should be allowed to use either mask or tube for delivery of aerosols or bronchodilators depending on his preference.

Mechanical consequences of airway smooth muscle relaxation.

Mechanical consequences of airway smooth muscle relaxation.