Biomedical subjects

A Wayne Evans

Publications and source records attributed to A Wayne Evans.

4 recordsLinked to original sources

PubMed2006

Hyperbaric oxygen results in an increase in rabbit calvarial critical sized defects.

OBJECTIVE: This study was undertaken to evaluate whether the effects of hyperbaric oxygen (HBO) therapy could alter the critical size for spontaneous healing of a bone defect in the rabbit calvarial model. STUDY DESIGN: An animal trial of 12 weeks duration was conducted using 20 New Zealand white rabbits, which were randomly divided into 2 groups of 10 animals each. Calvarial defects were created in the parietal bones of each animal bilaterally. Defects were critical-sized, 15 mm on one side and supra-critical-sized, 18 mm on the contralateral side. Group 1 received a 90-min HBO treatment sessions at 2.4 absolute atmospheric pressure (ATA) per day for 20 consecutive days. Group 2 served as a control without any HBO treatment sessions. Five animals in each group were sacrificed at 6 and 12 weeks. Data analysis included qualitative assessment of the calvarial specimens, post-sacrifice radiographs, as well as histomorphometric analysis to compute the amount of regenerated bone within the defects. ANOVA and paired sample t test were used for statistical analysis. RESULTS: Both radiographic analysis and histomorphometric analysis demonstrated that HBO-treated animals had significantly more new bone within their defects compared with the control group (P < .001). There was no statistically significant difference between the percentage of new bone forming in the 15-mm and 18-mm HBO-treated defects. There was no difference between the 6-week and the 12-week HBO-treated groups. HBO is effective in enhancing the bony healing of full thickness critical sized as well as supra-critical-sized defects in the rabbit calvarial model. CONCLUSION: Bone regeneration was significantly greater in the HBO-treated animals regardless of the defect size. HBO may have increased the diameter of the rabbit critical-sized calvarial defect to more than 18 mm.

Analysis of Variance↗

PubMed2006

Ischemic scleroderma wounds successfully treated with hyperbaric oxygen therapy.

Hyperbaric oxygen therapy (HBOT) has been used to treat refractory wounds for the last several decades, with the majority of research focusing on wounds secondary to arterial insufficiency. We describe 2 patients with scleroderma with intractable bilateral extremity ulcers. Local ischemia was identified using transcutaneous oximetry. Each patient then underwent 30 treatments of HBOT at a relative depth of 2.4 ATA with resulting wound healing. This is the first reported successful use of HBOT to treat scleroderma ulcers, and may represent an unrecognized treatment option for these notoriously difficult chronic wounds.

Adult↗

PubMed2005

Treatment of radiation proctitis with hyperbaric oxygen.

BACKGROUND AND PURPOSE: Radiation proctitis is a potential complication following pelvic radiation therapy. There are no standard treatments and treatment outcomes are unpredictable. We report our experience with the use of hyperbaric oxygen treatment (HBOT) for radiation proctitis cases refractory to standard medical or laser therapy. PATIENTS AND METHODS: During the period 2000-2004, 10 patients with radiation proctitis were treated with HBOT (three males and seven females; mean age of 65). The median follow-up period was 25 months (range 6-43 months). Patient symptoms were retrospectively scored prior to, and following HBOT, based on the LENT-SOMA scale. RESULTS: Prior to treatment, three patients had Grade 3 toxicity (i.e. requiring blood transfusions) and seven had Grade 2 toxicity with dominant symptoms of rectal pain and/or diarrhoea. HBOT was well tolerated and 9 of the 10 patients completed a full HBOT treatment program. Rectal bleeding completely stopped in four of nine symptomatic patients and improved in three others. Rectal pain completely remitted in three of five symptomatic patients. Diarrhea remitted completely in one of five patients and improved in three others. Of the 10 patients treated, only two did not respond to HBOT. CONCLUSIONS: Significant improvement of rectal bleeding, diarrhea and rectal pain is possible using HBOT. HBOT should be offered to patients who fail conventional treatments for radiation proctitis.

Adult↗

PubMedDate not supplied

MEASURE: A proposed assessment framework for developing best practice recommendations for wound assessment.

The effective management of nonhealing wounds is based on a complete patient history, a detailed initial assessment of the wound, and an analysis of probable causative factors. This information is used to individualize a management strategy to the underlying pathophysiology preventing healing and to implement appropriate wound interventions. Regular reassessment of progress toward healing and appropriate modification of the intervention are also necessary. Accurate and clinically relevant wound assessment is an important clinical tool, but this process remains a substantial challenge. Wound assessment terminology is nonuniform, many questions surrounding wound assessment remain unanswered, agreement has yet to be reached on the key wound parameters to measure in clinical practice, and the accuracy and reliability of available wound assessment techniques vary. This article, which resulted from a meeting of wound healing experts in June 2003, reviews clinically useful wound measurement approaches, provides an overview of the principles and practice of chronic wound assessment geared to a clinical audience, and introduces a simple mnemonic, MEASURE. MEASURE encapsulates key wound parameters that should be addressed in the assessment and management of chronic wounds: Measure (length, width, depth, and area), Exudate (quantity and quality), Appearance (wound bed, including tissue type and amount), Suffering (pain type and level), Undermining (presence or absence), Reevaluate (monitoring of all parameters regularly), and Edge (condition of edge and surrounding skin). This article also provides some preliminary recommendations targeted to developing best practice guidelines for wound assessment.

Chronic Disease↗