Elevated Imposed Work of Breathing Masquerading as Ventilator Weaning Intolerance

Kirton, Orlando C.; DeHaven, C. Bryan; Morgan, J.; Windsor, Jimmy; Civetta, Joseph M.

doi:10.1378/chest.108.4.1021

Cited by 77 publications

(50 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Imposed resistance through any or all of the airways during exhalation can produce alveolar hyperinflation, uneven regional ventilation, and excessive respiratory muscle loading, leading to increased work of breathing, impaired gas exchange, 16 and failure to wean. [17][18][19][20][21][22] As expected, the pressure-relief valve had an appreciable effect on the magnitude and frequency of the ⌬P tracheal (see Figs. 6 and 7) but did little to decrease mean P tracheal (see Fig.…”

Section: Discussionmentioning

confidence: 73%

Effects of Condensate in the Exhalation Limb of Neonatal Circuits on Airway Pressure During Bubble CPAP

2013

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 73%

Effects of Condensate in the Exhalation Limb of Neonatal Circuits on Airway Pressure During Bubble CPAP

2013

View full text Add to dashboard Cite

“…[50][51][52] Oto et al 53 found that reduction in ETT resistance precludes the automatic tube compensation ventilator feature from completely overcoming ETT resistance. It also reinforces the fact that humidification devices should be chosen based on suspected duration of use, patient condition, and presence of thick secretions.…”

Section: Heated Humidification Versus Heat-and-moisture Exchangers Fomentioning

confidence: 99%

Management of the Artificial AirwayDiscussion

2014

View full text Add to dashboard Cite

Management of the artificial airway includes securing the tube to prevent dislodgement or migration as well as removal of secretions. Preventive measures include adequate humidification and appropriate airway suctioning. Monitoring airway patency and removing obstruction are potentially life-saving components of airway management. Cuff pressure management is important for preventing aspiration and mucosal damage as well as assuring adequate ventilation. A number of new monitoring techniques have been introduced, and automated cuff pressure control is becoming more common. The respiratory therapist should be adept with all these devices and understand the appropriate application and management.

show abstract

“…For the 6 rats in which both lungs were exposed, the mean lesion depths were 3.3 mm for both the left and right lungs (left range, 2.2-4.3 mm; right range, 1.8-4.9 mm). The lesion surface area and volume were slightly more than doubled between the one-and two-sided exposed lungs (mean surface areas, 81 versus 181 mm 2 ; mean volumes, 97 versus 216 mm 3 ), as graphically shown in Figure 4.…”

Section: Lesion Sizementioning

confidence: 74%

“…1,2 The degree of abnormal function is dependent on the severity of injury and the proportion of total lung volume damaged. Because of the very large reserve volume of the lungs, which is required during exhaustive exercise, patients can accommodate rather severe lung damage and still survive.…”

mentioning

confidence: 99%

Cardiopulmonary function in rats with lung hemorrhage induced by pulsed ultrasound exposure.

Kramer

Waldrop

Frizzell

et al. 2001

J of Ultrasound Medicine

View full text Add to dashboard Cite

Objective. To assess cardiopulmonary function in rats exposed to pulsed ultrasound using superthreshold exposure conditions known to produce significant lung hemorrhage. Methods. In 1 group of 9 anesthetized SpragueDawley rats, 5 foci of ultrasound-induced hemorrhage were produced in the left lung of each rat. In a second group of 6 rats, 5 foci of ultrasound-induced hemorrhage were produced in the left and right lungs of each rat. Each lesion was induced using superthreshold pulsed ultrasound exposure conditions (3.1-MHz center frequency, 1.7-kHz pulse repetition frequency, 1.3-microsecond pulse duration, 60-second exposure duration, 39-MPa in situ peak compressional pressure, and 17-MPa in situ peak rarefactional pressure). After exposure, the lungs were fixed in formalin and assessed histologically. The total lesion volume was calculated for each lesion in each lung lobe. Measurements of cardiopulmonary function included assessment of pulsatile arterial pressure, heart rate, end-tidal carbon dioxide, respiratory rate, and arterial blood gases (PCO 2 and PO 2 ). Functional data were quantified before (baseline) and 30 minutes after exposure to ultrasound. Results. In the 9 rats that had lesions in only the left lung, the mean (SEM) lesion volume was 97 (13) mm 3 and represented about 3.4% of the total lung volume. In the 6 rats that had lesions in both the left and right lungs, the left, right, and total mean lesion volumes, respectively, were 102 (16), 114 (11), and 216 (18) mm 3 and represented about 3.7%, 4.2%, and 7.9% of the total lung volume. There were no statistically significant differences in cardiopulmonary measurements between baseline values and values obtained after exposure to ultrasound in the 9 rats exposed on the left lung only. The 6 rats exposed bilaterally had statistically significant differences in arterial pressure (134 ± 4 versus 113 ± 9 mm Hg; P = .047) and arterial PO 2 (70 ± 5 versus 58 ± 4 mm Hg; P = .024) between baseline values and values obtained after exposure to ultrasound. Conclusions. The severity of ultrasound-induced lesions produced in 1 lung did not affect measurements of cardiopulmonary function because of the functional respiratory reserve in the unexposed lung. However, when both the left and right lungs had ultrasound-induced lesions, the functional respiratory reserve was decreased to a point at which rats were unable to maintain systemic arterial pressure or resting levels of arterial PO 2 .

show abstract

Elevated Imposed Work of Breathing Masquerading as Ventilator Weaning Intolerance

Cited by 77 publications

References 16 publications

Effects of Condensate in the Exhalation Limb of Neonatal Circuits on Airway Pressure During Bubble CPAP

Effects of Condensate in the Exhalation Limb of Neonatal Circuits on Airway Pressure During Bubble CPAP

Management of the Artificial AirwayDiscussion

Cardiopulmonary function in rats with lung hemorrhage induced by pulsed ultrasound exposure.

Contact Info

Product

Resources

About