1995 OPEN FORUM Abstracts
EARLY EXPERIENCE WITH AN APPROPRIATENESS GUIDELINE FOR SAMPLING ARTERIAL BLOOD GASES IN AN ICU.
Perez- Trepichio P. BS, RRT, Stoller J.K. MD. Cleveland Clinic Foundation, Cleveland, Ohio.
Available studies suggest that over-ordering of arterial blood gases (ABGs) occurs commonly in Intensive Care Units and can be lessened by implementing guidelines for appropriate ABG sampling. To assess the appropriateness of current ABG sampling in our Medical Intensive Care Unit and as a possible basis for implementing future guidelines, we undertook this retrospective audit. Using AARC Clinical Practice Guidelines and published protocols for ABG sampling an algorithm was drafied and applied to 100 ABGs drawn from 13 randomly selected adult Medical Intensive Care Unit patients on mechanical ventilation (mean 7.7 ABGs/patient, range 5 to 12). Reasons for needing ICU care included respiratory failure (46% [n=6]), ARDS (23% [n=3]), pneumonia (15% [n=2]), COPD (8% [n=1]) and CHF (8% [n=1]). Indwelling arterial lines and continuous pulse oximetry were used in all patients. Conclusions regarding the appropriateness of sampling ABGs were made by a single observer (PP-T) based on retrospective review of medical records. Of the 100 ABGs reviewed, 56% did not satisfy appropriateness criteria according to the algorithm. Seventy five per cent of these 56 ABGs did not prompt any adjustment of the mechanical ventilator or of the inspired oxygen concentration. All 13 patients underwent at least one ABG sample that was not deemed indicated. Furthermore, in 2 patients (3 occurrences), the algorithm called for an ABG sample that was not obtained. The results of this preliminary retrospective audit suggest that: 1. As in other series, over-ordering of arterial blood gases occurs commonly in our Medical Intensive Care Unit, 2. Under-ordering of ABGs is also observed, but occurs less commonly, 3. Blood gases that were drawn inappropriately frequently failed to prompt any adjustment of therapy to improve oxygenation or ventilation, 4. Further research should assess features of patients and caregivers that accompany over-ordering and strategies to improve the allocation of ABG sampling in the intensive care unit.