Conference Proceedings - School of Nursing & Midwifery - Trinity ...

School of Nursing & Midwifery, Trinity College Dublin: 8 th Annual Interdisciplinary Research Conference
Transforming Healthcare Through Research, Education & Technology: 7 th – 9 th November 2007
Conference Proceedings
In this instance sub-maximal incremental work rate was measured
using the Bruce protocol on patients both pre and post programme.
Two protocols were enacted during the time course of the study the
exercise stress test was stopped at 13 METS or 13.5METS. The
recommended guidelines for the termination of the stress test and
exclusion criteria for exercise were applied. Subsequently the
Karvoren method was used to calculate target heart rate and
exercise prescription was set at a maximum of 60% VO2 max.
Data Collection: The patient demographics and clinical details were
collected from the case notes.
Analysis: SPSS version 14 was used for statistical analysis. T-tests
were used to determine if there were significant improvements from
pre and post VO2 max. Linear regression was used to determine the
predictors of fitness and changes in fitness. Fitness as indicated by
VO2 max in mg/kg/min was classified into categories using AHA
(American Heart Association) categories so as to take age and
gender into account (Cooper & Storer 2001).
Ethics: Permission for the study was granted by the ethics
committee of the hospital concerned and conforms to the principles
outlined in the Declaration of Helsinki.
Results:
The sample was made up of 134 males and 53 females. From a
diagnosis point of view the sample was composed of 80 myocardial
infarctions (MI), 56 coronary artery bypass grafts (CABG), 34
percutaneous transluminal coronary angioplasty (PTCA), 4 other
surgery patients and 13 others. The age profile of the sample
ranged from 30-81 the average age being 59.33±9.58 years. The
body mass index (BMI) of the patients were (n=111): 12% normal
or less than normal BMI (≤ 25), 55% overweight (25-29.9 BMI) and
33% were obese or severely obese (BMI ≥30). Pre programme
exercise stress test results gave a mean MET’s value of 9.02±2.99
(n= 179), of which 63% could be classified as sedentary (MET’s ≤
10 Balady et al 2000). Out of the 179 patients that did the pre
programme exercise stress test a total of 16.9% reached the
maximum level when the test was stopped and therefore exhibited
a ceiling effect. In the post programme exercise stress test a mean
of 10.10 ± 2.66 MET’s (n=122) was achieved, indicating that now
only 55.7% were sedentary. Out of the 122 patients who did the
post programme exercise stress test post programme 33% were
stopped at the maximum level. The overall mean improvement in
fitness was 1.04±2.56 MET’s.
Using the paired two tailed t test there was a significant difference
between pre programme fitness and post programme fitness (n=71,
t value= 0.035 significant at 0.05 level)
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