Anxiety sensitivity and ventilator weaning: A preliminary analysis

Abstract

Ventilator weaning, the restoration of independent breathing in an individual dependent on mechanically assisted ventilation, involves gradually exposing the individual to longer periods of partially supported or independent breathing. Although ventilator weaning success is importantly related to disease or injury severity, psychological factors have been implicated in weaning outcome but remain significantly understudied. We evaluated the relationship between anxiety sensitivity (AS), an individual difference variable implicated in reactivity to stressors, and weaning success and distress in 38 mechanical ventilator-dependent patients. Equivalent evaluations were conducted with trait anxiety and depression measures for comparison. Fear of the bodily sensations associated with anxious arousal (a subcomponent of AS) and depression scores were significantly correlated with the highest level of independent ventilation achieved in early weaning trials. Fear of the bodily sensations associated with anxious arousal was significantly correlated with patient reported anxiety during weaning, even after controlling for trait anxiety and depression. Implications for the clinical management of ventilator weaning are discussed.

Keywords:

• Anxiety sensitivity
• depression
• respiratory illness
• respiratory failure

Notes

1. Unspecified respiratory failure was frequently associated with chronic disease (e. g., type I diabetes) or neurological injury (e. g., cerebral vascular accident). Several participants had different respiration-affecting illnesses. Participants had many additional medical disorders that were not directly related to respiratory failure (e. g., cardiovascular disease).

2. Because this instrument is a very brief cognitive functioning screen that provides limited information, we used it as only a screening tool and did not maintain patients’ scores (other than pass/fail). Therefore, we cannot compare our sample to norming samples on this measure.

3. Participants completed affect measures several hours to several days before initial weaning. If an individual agreed to participate in the study only shortly before their initial weaning trial, the interval was short.

4. In analyses with the total APACHE-II score as the disease severity measure, several differences were observed in weaning success and distress analyses: disease severity was not a predictor of the Index Score in Step 1; Step 2 variables were unrelated to baseline anxiety in analyses that included ASI total score, and Step 2 change was not significant in the model with ASI total score or ASI-Physical Concerns in the prediction of anxiety reported 5 min before a weaning trial.