Biobehavioral Effects of Therapy Dog Visitation in Elderly Intensive Care Unit Patients: A Pilot and Feasibility Study

Change in stress as assessed by the Stress-Visual Analog Scale

Time Frame: immediately before TDV, immediately after TDV

Stress will be measured using the Stress-Visual Analog Scale which is a tool used in intensive care unit (ICU) settings that consists of a small, unmarked 100mm ruler with endpoints labeled "none" and "as bad as it could be". Participants indicate how stressed they feel on the ruler, which yields a single subjective stress score between 0 and 100. The Stress visual analogue scale (VAS) demonstrates acceptable validity between the VAS and the Hospital Anxiety and Depression (HADS) total score with correlations of r = 0.65.

Change in biological inflammatory stress responses as assessed by salivary interleukin-1beta (IL-1β) levels

Time Frame: immediately before TDV, immediately after TDV

Saliva samples will be assayed using standardized enzyme immunoassay (EIA) kits (Salimetrics, State Park: PA). For IL-1β, intra-assay CV ranges between 2-3% and inter-assay CV is 4.5%. Sensitivity of the EIA kit is 0.6 pg/mL.

Change in biological stress response as assessed by salivary cortisol levels

Time Frame: immediately before TDV, immediately after TDV

Saliva samples will be assayed using standardized enzyme immunoassay (EIA) kits (Salimetrics, State Park: PA). For cortisol, intra-assay coefficient of variation (CV) ranges between 4%-7% and inter-assay CV ranges between 3%-11%. Sensitivity of the EIA kit is .0007 μg/mL.

Change in biological inflammatory stress responses as assessed by salivary C-reactive protein (CRP) levels

Time Frame: immediately before TDV, immediately after TDV

Saliva samples will be assayed using standardized enzyme immunoassay (EIA) kits (Salimetrics, State Park: PA). For CRP, intra-assay CV ranges between 1.9%-5.9% and inter-assay CV ranges between 3.7%-11.2%. Sensitivity of the EIA kit is 10 pg/mL.

Change in Anxiety as assessed by the Faces Anxiety Scale

Time Frame: immediately before TDV, immediately after TDV

Anxiety will be measured using the FACES Anxiety Scale, a brief single-item, five-point self-report scale commonly used in the ICU consisting of 5 faces representing an increased level of anxiety, where the first item represents a "no anxiety" face (Elkman \& Friesen; 1975). The FACES Anxiety Scale is a commonly used instrument in the ICU and proposed by the American Association of Critical-Care Nurses and demonstrates acceptable criterion validity between the FACES Anxiety Scale and State Anxiety Inventory total score in ventilated and non-ventilated ICU patients with correlations of r =.70; p\<0005.

Change in Mood as assessed by the Positive and Negative Affect Schedule

Time Frame: immediately before TDV, immediately after TDV

Measures for mood (positive/negative affect) will be measured using the Positive and Negative Affect Schedule (PANAS). The PANAS is an established 20-item instrument that uses a 5-point Likert scale and includes single words that express negative and positive moods. The instructions on the instrument would be revised to state, "indicate how you feel right now" rather than "indicate how you felt in the last week." Sample answers include "excited", "scared", "nervous", and "enthusiastic," etc. (Craword \& Henry, 2004).