Blood flow responses over sacrum in nursing home residents during one hour bed rest

Effect of interface pressure and skin surface temperature on pressure injury incidence: a turning schedule pilot study

OBJECTIVE

This study aimed to evaluate the interface pressure and skin surface temperature in relation to the incidence of pressure injury (PI) using three different turning schedules.

METHOD

This was a pilot study with a three-armed randomised clinical trial design. Participants at risk of PI and treated in the high dependency care unit in a regional hospital in Makassar, Indonesia participated in this study. Patients were repositioned at three different turning schedules (two-, three- and four-hourly intervals). Interface pressure measurement and skin surface temperature were measured between 14:00 and 18:00 every three days. The incidence of PI was assessed during the two-week observation period.

RESULTS

A total of 44 participants took part in the study. A one-way ANOVA test revealed no difference in interface pressure among the three different turning schedule groups within two weeks of observations: day zero, p=0.56; day four, p=0.95; day seven, p=0.56; day 10, p=0.63; and day 14, p=0.92. Although the average periumbilical temperature and skin surface temperature were not significant (p>0.05), comparison between these observation sites was significant on all observation days (p<0.05). Regarding the incidence of PI, the proportional hazard test for the development of PI in the three groups was considered not different (hazard ratio: 1.46, 95% confidence interval: 0.43-4.87, p=0.54).

CONCLUSION

No difference in interface pressure and incidence of PI on the three turning schedules was observed; however, there was a potential increase in skin surface temperature in comparison with periumbilical temperature for all three turning schedules.

A Systematic Review and Meta-Analysis of the Pressure-Induced Vasodilation Phenomenon and Its Role in the Pathophysiology of Ulcers

BACKGROUND

Physiologic studies show that tissue perfusion increases during moderate amounts of tissue compression. This is attributed to sensory nerves initiating a vasodilatory cascade referred to as pressure-induced vasodilation.

METHODS

PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched for studies investigating perfusion during pressure exposure longer than 10 minutes. Retrieved studies were assessed using the Office of Health Assessment and Translation Risk of Bias Rating Tool for Human and Animal Studies. Results were pooled with random effects models. The body of evidence was rated using the Office of Health Assessment and Translation approach.

RESULTS

Twenty-nine articles were included, of which 19 articles were included in meta-analyses. The evidence indicates that moderate amounts of tissue compression have the capacity to increase perfusion in healthy humans by 46 percent (95 percent CI, 30 to 62 percent). Using the Office of Health Assessment and Translation approach, the authors found a high level of confidence in the body of evidence. Pressure-induced vasodilation blockade was associated with increased pressure ulcer formation. Pressure-induced vasodilation was impaired by neuropathy and by the drugs diclofenac and amiloride.

CONCLUSIONS

This systematic review and meta-analysis indicates that healthy humans have the capacity to increase local perfusion in response to mechanical stress resulting from tissue compression. Because pressure-induced vasodilation is mediated by sensory nerves, pressure-induced vasodilation emphasizes the importance of sensory innervation for durable tissue integrity. Pressure-induced vasodilation impairment seems to provide a complementary explanation for the susceptibility of neuropathic tissues to pressure-induced lesions.

Blood flow responses over sacrum in nursing home residents during one hour bed rest

Objectives

To describe individual BF responses in a nursing home resident population for one‐hour periods of bed rest.

Methods

BF was measured for one hour over the sacrum in 0° supine position and 30° supine tilt position in 25 individuals aged 65 y or older while lying on a pressure‐redistributing mattress. Measurements were made at three tissue depths (1, 2, and 10 mm) using the noninvasive optical techniques, LDF and PPG.

Results

Eleven participants had a PIV response at 1 mm depth in both positions and seven participants had a lack of this response at this depth and positions. The BF response at 1 mm depth appeared immediately and remained over, or below, baseline for the entire 60 min of loading in both positions. These BF patterns were also seen in deeper tissue layers.

Conclusions

The cutaneous BF response among the nursing home residents was distinct, appeared early, and remained during the one hour of loading.