INTUBATED PATIENTS FALL OUTSIDE OF TARGET RECUMBENCY RANGE FOR THE PREVENTION OF VENTILATOR ASSOCIATED PNEUMONIA AT ONE ACADEMIC MEDICAL CENTER, AS MEASURED BY NOVEL DIGITAL SENSOR, ANGULUS

Background: Ventilator associated pneumonia (VAP) is the leading cause of death from nosocomial infections in critically-ill patients. The CDC recommends maintaining Head-of-Bed (HOB) elevation at a target recumbency range of 30º-45º due to evidence that a semi-recumbent position significantly reduces VAP. Current methods for evaluating patient recumbency utilize “eyeballing” or built-in HOB protractors, which are limited by human error and misalignment between patient and bed orientations, possibly compromising compliance with best-practice guidelines. We used a novel, validated digital sensor, Angulus, which attaches to the patient’s chest to directly measure the recumbency angle in intubated patients and to determine average time spent in the target range.

Methods: We conducted a feasibility trial using the Angulus sensor to measure average time spent in the target range in ICU patients. We first provided didactic sessions for ICU nurses that included education on VAP prevention and introduction to the Angulus sensor. Patients on Mechanical Ventilation (MV) for whom sensor placement and HOB elevation were not contraindicated were prospectively enrolled in three ICUs. The Angulus sensor was secured to each patient’s chest and the recumbency angle was monitored and recorded continuously on an accompanying iPod device. Study termination for each patient occurred upon extubation, ICU discharge on MV, death, or day 14 on MV, whichever came first.

Results: A total of 90 patients were enrolled (43 (48%) in ICU A, 21 (23%) in ICU B, and 26 (29%) in ICU C). Overall, patients spent an average of 35%±25% of their MV period with HOB elevation between 30º-45º and an average of 74%±23% of their MV time at HOB elevation between 20º-55º. Patients in ICU B spent a greater average percentage of MV time with HOB elevation between 30º-45º (mean 48%±27% vs mean 31%±25% in ICU A and mean 31%±20% in ICU C; p=0.05). No significant difference in average percentage of time on MV spent at 20º-55º was found between ICUs (72%±24% in ICU A, 81%±23% in ICU B, 71%±22% in ICU C; p=0.1). No significant difference in average time spent in these two ranges was identified by race, ethnicity, and gender (p>0.6).

Conclusions: Our study found that when the actual angle of the patient torso rather than the angle of the bed is measured, intubated patients at our combined ICUs spent only about 1/3 of MV time with HOB elevation at 30º-45º and 3/4 of MV time with HOB elevation at 20º-55º. This suboptimal compliance may be the result of several contributing factors, including but not limited to: patient-specific barriers (e.g. elevated BMI), inadequate staffing, and lack of understanding of how the device angle measurements differ from HOB measurements.