Methods: Electronic health record data were used to identify patients with Stage 2 HAPIs among surgical critical-care patients at a level-1 trauma center and academic medical center in the United States between September 1, 2008 and May 1, 2014. Univariate Cox regressions were used to identify factors associated with nonhealing Stage 2 HAPIs (present at discharge) using R version 3.3.4 via the R studio interface. Demographic data included age, race, and sex. Potential predictor variables included Braden Scale scores and subscale scores, the Confusion Assessment Method-ICU (a measure of delirium), the Riker score (a measure of sedation/agitation), duration of surgery, serum lactate, serum creatinine, glucose, hemoglobin, albumin, and body mass index. Because delivery of oxygen-rich blood (perfusion) is an important factor in PI development and also contributes to wound healing (Bly, Schallom, Sona, & Klinkenberg, 2016; Coleman et al., 2014; Cox & Roche, 2015) we also collected data about blood pressure and oxygenation. We defined low sp02 (low oxygenation) as three consecutive sp02 measures taken at least 15 minutes apart < 90% (e.g., sp02 < 90% sustained for > 45 minutes). Similarly, we defined low blood pressure as three consecutive systolic blood pressures < 90mmHg that were taken at least 15 minutes apart.
Results: Among 6,376 surgical critical-care patients, 298 (4.6%) developed Stage 2 HAPIs; complete data were available for 253 patients. Among the 253 patients, 160 (63%) had unhealed HAPIs at hospital discharge. The mean age of patients in the sample was 59 (+/– 16 years), and most were White (n = 200, 79%) and male (n = 152, 60%). The mean length of stay for patients in our sample was 30 (SD = 24 days). The mean duration of hospitalization from admission to Stage 2 PI development was 14 days (+/– 14 days), whereas the mean length of time from Stage 2 development until discharge was 15 days (+/– 18 days). Factors significantly related to risk for nonhealing HAPIs were older age (HR = 0.98, 95% CI = 0.97–0.99, p = 0.003), elevated serum lactate (HR = 0.85, 95% CI = 0.75–0.96, p = 0.011), elevated serum creatinine (HR = 0.87, 95% CI = 0.77–0.98, p = 0.021), and lower oxygenation (sp02; HR = 0.64, 95% CI = 0.41–1.0, p = 0.051).
Conclusion: Among 253 surgical critical-care patients with Stage 2 HAPIs, 160 (63%) did not experience healing by the time of hospital discharge. Factors associated with risk for unhealed Stage 2 HAPIs were older age, elevated serum lactate, decreased oxygenation, and elevated serum creatinine. The parameters of the Braden Scale and its subscales were not associated with healing outcomes in the current study, whereas a prior study found that Braden Scale scores were associated with healing outcomes generally among medical/surgical patients (Karahan et al., 2018). Nurses should consider all patients with Stage 2 PIs as being at risk for nonhealing (Boyko, Longaker, & Yang, 2018), and should be especially vigilant in treatment of patients with Stage 2 injuries who are older, have altered perfusion (as indirectly evidenced by elevated serum lactate or decreased sp02), and who have evidence of renal compromise or failure.