Myoendothelial feedback in mouse mesenteric resistance arteries is similar between the sexes, dependent on nitric oxide synthase, and independent of TPRV4.

Myoendothelial feedback (MEF), the endothelium-dependent vasodilation following sympathetic vasoconstriction (mediated by smooth muscle to endothelium gap junction communication), has been well studied in resistance arteries of males, but not females. We hypothesized that MEF responses would be similar between the sexes, but different in the relative contribution of the underlying nitric oxide and hyperpolarization mechanisms, given that these mechanisms differ between the sexes in agonist-induced endothelium-dependent dilation. We measured MEF responses (diameter changes) of male and female first- to second-order mouse mesenteric arteries to phenylephrine (10 µM) over 30 min using isolated pressure myography ± blinded inhibition of nitric oxide synthase (NOS) using Nω-nitro-l-arginine methyl ester (l-NAME; 0.1-1.0 mM), hyperpolarization using 35 mM KCl, or transient receptor potential vanilloid 4 (TRPV4) channels using GSK219 (0.1-1.0 µM) or RN-1734 (30 µM). MEF was similar [%dilation (means ± SE): males = 26.7 ± 2.0 and females = 26.1 ± 1.9 at 15 min] and significantly inhibited by l-NAME (1.0 mM) at 15 min [%dilation (means ± SE): males = 8.2 ± 3.3, P < 0.01; females = 6.8 ± 1.9, P < 0.001] and over time (P < 0.01) in both sexes. l-NAME (0.1 mM) + 35 mM KCl nearly eliminated MEF in both sexes (P < 0.001-0.0001). Activation of TRPV4 with GSK101 (0.1-10 µM) induced similar dilation between the sexes. Inhibition of TRPV4, which is reportedly involved in the hyperpolarization mechanism, did not inhibit MEF in either sex. Similar expression of eNOS was found between the sexes with Western blot. Thus, MEF is prominent and similar in murine first- and second-order mesenteric resistance arteries of both sexes, and reliant primarily on NOS and secondarily on hyperpolarization, but not TRPV4.NEW & NOTEWORTHY We found that female mesenteric resistance arteries have similar postconstriction dilatory responses (i.e., myoendothelial feedback) to a sympathetic neurotransmitter analog as male arteries. Both sexes use nitric oxide synthase (NOS) and hyperpolarization, but not TRPV4, in this response. Moreover, the key protein involved in this pathway (eNOS) is similarly expressed in these arteries between the sexes. These similarities are surprising given that agonist-induced endothelium-dependent dilatory mechanisms differ in these arteries between the sexes.

Revalidation of a Perioperative Risk Assessment Measure for Skin.

BACKGROUND: Validated perioperative pressure injury (PI) risk assessment measures are few and often cumbersome to complete, leading to missed opportunities to identify and target prevention interventions to those patients at increased risk for developing a postsurgical PI. OBJECTIVES: Previous validation of a six-item perioperative risk assessment measure for skin (PRAMS) was conducted in our community hospital with positive findings. The purpose of this study was to increase generalizability by revalidating the PRAMS in a larger sample. METHODS: This was a retrospective chart review of all surgical patients aged ≥18 years positioned in the supine or lateral position in a Midwest quaternary care, multispecialty, 1,500-bed hospital during a 6-month period (n = 1,526). The intent of the study was to revalidate the PRAMS. The main outcome of interest was the development of PI after surgery. Risk indicators of interest included diabetes, age, surgical time, Braden score, previous surgery, and preexisting PI. The diagnostic ability of any of the risk indicators on the development of a postsurgical PI was evaluated using sensitivity, specificity, and predictive values. RESULTS: Postsurgical PIs occurred in 121 patients. Comparing current to previous study results, the PRAMS was effective in identifying surgical patients at risk for PI (sensitivity = .98). Those patients with a postsurgical PI had a lower mean Braden score, were more likely to have a preexisting PI, and were more likely to have a previous surgery during the same admission (p < .001 for all risk indicators), comparing favorably to the original study. Patients without risk indicators were unlikely to develop a postsurgical PI (negative predictive value = .98). DISCUSSION: Results of this validation study demonstrate that the PRAMS is effective in identifying patients who developed a postsurgical PI using information readily available to the perioperative staff.

A Nurse-Initiated Perioperative Pressure Injury Risk Assessment and Prevention Protocol.

Pressure injuries negatively affect patients physically, emotionally, and economically. Studies report that pressure injuries occur in 69% of inpatients who have undergone a surgical procedure while hospitalized. In 2012, we created a nurse-initiated, perioperative pressure injury risk assessment measure for our midwestern, urban, adult teaching hospital. We retrospectively applied the risk assessment to a random sample of 350 surgical patients which validated the measure. The prospective use of the risk assessment and prevention measures in 350 surgical patients resulted in a 60% reduction in pressure injuries compared with the retrospective group. Our findings support the use of a multipronged approach for the prevention of health care-associated pressure injuries in the surgical population, which includes assessment of risk, implementation of evidence-based prevention interventions for at-risk patients, and continuation of prevention beyond the perioperative setting to the nursing care unit.

Development of a Nutrition Screening Tool for an Outpatient Wound Center.

OBJECTIVE: To construct a quickly and easily administered nutrition screening tool using variables believed to be predictive of malnutrition risk in the wound patient population. DESIGN: A prospective pilot study assessed patients on a list of suspected variables, as well as the Scored Patient-Generated Subjective Global Assessment (PG-SGA), chosen as the criterion standard. Variables were analyzed to select the most appropriate items for inclusion on a new nutrition screening tool using preliminary bivariate correlations and χ tests of association. Items significantly associated with malnutrition were dichotomized, and binary logistic regression analyses were performed to arrive at a final model. A sum score was computed, and receiver operating characteristic analysis was used to determine designation of risk. SETTING: An outpatient wound center in Northeast Ohio. PARTICIPANTS: The pilot study included a convenience sample of 105 outpatients with at least 1 active wound. MAIN OUTCOME MEASURES: Malnutrition as assessed by the Scored PG-SGA. MAIN RESULTS: The final nutrition screening tool, the MEAL Scale, is composed of 4 dichotomous elements: multiple wounds (number of wounds), eats less than 3 meals per day, appetite decrease (eats less than usual), and level of activity. These variables predicted 83.7% of the malnutrition cases assessed by the Scored PG-SGA. The receiver operating characteristic analysis showed an acceptable area under the curve (0.8581), and a cutoff score of 2 or greater was selected to indicate risk (median sensitivity = 91.4%, median specificity = 60.9%). CONCLUSIONS: Although further studies of validity and reliability are necessary to establish the tool before widespread use, the MEAL Scale is a needed step toward nutrition screening in a wound patient population.

Resource nurse program: A nurse-initiated, evidence-based program to eliminate hospital-acquired pressure ulcers.

This article describes the process used to establish a systemwide, sustainable team of staff nurses to serve as unit-based resource nurses charged with aiding colleagues in the assessment, treatment, and prevention of pressure ulcers. A multidisciplinary program was developed to address barriers in preventing hospital-acquired pressure ulcers, including incomplete knowledge of causative factors, confusion in determining wound etiology, incorrect staging, inaccurate Braden Scale scoring, and inconsistent application of evidence-supported prevention interventions. The Resource Nurse Program was initiated in a community-based 511-bed, acute care teaching hospital located in the Midwestern United States.

A prospective, in vivo evaluation of two pressure-redistribution surfaces in healthy volunteers using pressure mapping as a quality control instrument .

Deep tissue injury (DTI) can rapidly evolve into a higher stage pressure ulcer. Use of pressure-redistribution surfaces is a widely accepted practice for the prevention of pressure ulcers in acute care patients, particularly in departments where care processes limit mobility. A 15-year-old patient developed a sacral DTI 24 hours after completion of a lengthy (12- hour) electrophysiology (EP) study and catheter ablation. A root cause analysis (RCA) conducted to investigate the origin of the hospital-acquired suspected DTI prompted a small investigation to evaluate the pressure-distribution properties of the EP lab surface and an OR table pad. Five healthy adult employee volunteers were evaluated in the supine position by placing a sensing mat between the volunteer and the test surface. Interface pressures (on a scale of 0 mm Hg to 100 mm Hg) were captured after a "settling in" time of 4 minutes, and the number of sensors registering very high pressures (above 90 mm Hg) across the surface were recorded. On the OR table pad, zero to six sensors registered >90 mm Hg compared to two to 20 sensors on the EP lab surface. These data, combined with the acquired DTI, initiated a change in EP lab surfaces. Although interface pressure measurements only provide information about one potential support surface characteristic, it can be helpful during an RCA. Studies to compare the effect of support surfaces in all hospital units on patient outcomes are needed.

How to start a nurse-managed foot care clinic.

The goals of a nurse-managed clinic are to prevent illness and encourage an active participation in health maintenance by increasing patient knowledge. A nurse-managed clinic that focuses on foot care presents an excellent opportunity to provide quality care to patients who are at risk by monitoring for debilitating foot conditions while teaching proper foot care techniques. It is well documented that foot care can prevent serious complications, such as amputation, making it essential for patients to be educated and receive professional foot care. This article addresses the development of a foot care clinic managed and staffed by nurses.