Correction of Hypoxia, a Critical Element for Wound Bed Preparation Guidelines: TIMEO2 Principle of Wound Bed Preparation

How does sleep apnea impact outcomes following primary total hip arthroplasty for femoral neck fractures: a matched-control analysis

BACKGROUND

Cross-sectional studies have demonstrated that the prevalence of sleep apnea (SA) to be increasing within the United States. While studies have shown the association of SA and its association on complications following elective orthopedic procedures, well-powered studies investigating its impact in a traumatic setting are limited. The purpose of this study was to determine whether SA patients undergoing primary total hip arthroplasty (THA) for femoral neck fractures have higher rates of: (1) hospital lengths of stay (LOS); (2) readmissions; (3) complications; and (4) healthcare expenditures.

METHODS

The 100% Medicare Standard Analytical Files was queried from 2005 to 2014 for patients who sustained femoral neck fractures and were treated with primary THA. The study group consisted of patients with concomitant diagnoses of SA, whereas patients without SA served as controls. Study group patients were matched to controls in a 1:5 ratio by age, sex, and various comorbid conditions. Demographics of the cohorts were compared using Pearson's chi-squared analyses, and multivariate logistic regression analyses were used to calculate the odds (OR) of the effects of SA on postoperative outcomes. A p value less than 0.006 was considered to be statistically significant.

RESULTS

The final query yielded 24,936 patients within the study (n = 4166) and control (n = 20,770) cohorts. SA patients had significantly longer in-hospital LOS (6 vs. 5 days, p < 0.0001) but similar readmission rates (24.12 vs. 20.50%; OR: 1.03, p = 0.476). SA patients had significantly higher frequency and odds of developing medical complications (72.66 vs. 43.85%; OR: 1.57, p < 0.0001), and higher healthcare costs ($22,743.79 vs. $21,572.89, p < 0.0001).

CONCLUSION

SA is associated with longer in-hospital LOS, higher rates of complications and healthcare expenditures. This study is vital as it can allow orthopaedists to educate patients with SA on the potential complications which may occur following their procedure.

LEVEL OF EVIDENCE

III.

Dissolved oxygen technologies as a novel strategy for non-healing wounds: A critical review

Non-healing wounds are steadily becoming a global-health issue. Prolonged hypoxia propagates wound chronicity; yet, oxygenating treatments are considered inadequate to date. Dissolved oxygen (DO) in aqueous solutions introduces a novel approach to enhanced wound oxygenation, and is robustly evaluated for clinical applications. A systematic literature search was conducted, whereby experimental and clinical studies of DO technologies were categorized per engineering approach. Technical principles, methodology, endpoints and outcomes were analysed for both oxygenating and healing effects. Forty articles meeting our inclusion criteria were grouped as follows: DO solutions (17), oxygen (O₂ ) dressings (9), O₂ hydrogels (11) and O₂ emulsions (3). All technologies improved wound oxygenation, each to a variable degree. They also achieved at least one statistically significant outcome related to wound healing, mainly in epithelialization, angiogenesis and collagen synthesis. Scarcity in clinical data and methodological variability precluded quantitative comparisons among the biotechnologies studied. DO technologies warrantee further evaluation for wound oxygenation in the clinical setting. Standardised methodologies and targeted research questions are pivotal to facilitate global integration in healthcare.

Role of oxygen in wound healing

Not only does oxygen play an essential role in each stage of the wound healing process. It also helps to increases host resistance to infection. Any impairment to the oxygen supply can therefore delay healing. This article explores the affects of oxygen on the wound cells and tissue, and explains how an adequate supply is required for granulation tissue formation and epithelialisation to occur

Amputation stump perfusion is predictive of post-operative necrotic eschar formation

Background

A large proportion of patients develop poor amputation stump healing. We hypothesize that Laser-Assisted Fluorescent Angiography (LAFA) can predict inadequate tissue perfusion and healing.

Methods

Over an 8-month period we reviewed all patients who underwent lower extremity amputation and LAFA. We evaluated intra-operative LAFA global and segmental stump perfusion, and post-operative modified Bates-Jensen (mBJS) wound healing scores.

Results

In 15 patients, amputation stumps with lower global perfusion demonstrated higher mBJS (P = 0.01). Lower suture-line perfusion also correlated with more eschar formation (P < 0.001). Diabetic patients had higher mBJS (P = 0.009), lower stump perfusion (P = 0.02), and increased eschar volume (P < 0.001).

Conclusion

LAFA is a useful adjunct for intra-operative stump perfusion assessment and can predict areas of poor stump healing and eschar formation. Diabetic patients seem to be at higher risk of stump eschar formation.

Vascular assessment of wound healing: a clinical review

Although macrovascular screening of patients with chronic wounds, particularly in the lower extremities, is accepted as part of clinical practice guidelines, microvascular investigation is less commonly used for a variety of reasons. This can be an issue because most patients with macrovascular disease also develop concomitant microvascular dysfunction. Part of the reason for less comprehensive microvascular screening has been the lack of suitable imaging techniques that can quantify microvascular dysfunction in connection with non-healing chronic wounds. This is changing with the introduction of fluorescence microangiography. The objective of this review is to examine macro- and microvascular disease, the strengths and limitations of the approaches used and to highlight the importance of microvascular angiography in the context of wound healing.

Antioxidant Response of Chronic Wounds to Hyperbaric Oxygen Therapy

We analyzed the effects of the clinical hyperbaric oxygen therapy (HBOT) on the plasma antioxidant response and levels of endothelin-1, Interleukine-6 (IL-6) and vascular endothelial growth factor (VEGF) in patients with chronic wounds (20.2±10.0 months without healing). They received 20 HBOT sessions (five sessions/week), and blood samples were obtained at sessions 1, 5 and 20 before and 2 hours after the HBOT. An additional blood sample was collected 1 month after wound recovery. Serum creatine kinase activity decreased progressively in accordance with the wound healing. Plasma catalase activity significantly increased after the first and fifth sessions of HBOT. Plasma myeloperoxidase activity reported significantly lower values after sessions. Plasma VEGF and IL-6 increased after sessions. Endothelin-1 levels were progressively decreasing during the HBOT, being significant at the session 20. Plasma malondialdehyde concentration was significantly reduced at the last session. Both creatine kinase activity and malondialdehyde levels were maintained lower 1 month after wound recovery respect to initial values. In conclusion, HBOT enhanced the plasma antioxidant defenses and may contribute to activate the healing resolution, angiogenesis and vascular tone regulation by increasing the VEGF and IL-6 release and the endothelin-1 decrease, which may be significant factors in stimulating wound healing.