Ontario health technology assessment series
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Ont Health Technol Assess Ser · Jan 2009
Management of chronic pressure ulcers: an evidence-based analysis.
In April 2008, the Medical Advisory Secretariat began an evidence-based review of the literature concerning pressure ulcers.Please visit the Medical Advisory Secretariat Web site, http://www.health.gov.on.ca/english/providers/program/mas/tech/tech_mn.html to review these titles that are currently available within the Pressure Ulcers series.PRESSURE ULCER PREVENTION: an evidence based analysisThe cost-effectiveness of prevention strategies for pressure ulcers in long-term care homes in Ontario: projections of the Ontario Pressure Ulcer Model (field evaluation)MANAGEMENT OF CHRONIC PRESSURE ULCERS: an evidence-based analysis ⋯ Findings from the analysis of the included studies are summarized below: CLEANSING: There is no good trial evidence to support the use of any particular wound cleansing solution or technique for pressure ulcers. DEBRIDEMENT: There was no evidence that debridement using collagenase, dextranomer, cadexomer iodine, or maggots significantly improved complete healing compared with placebo.There were no statistically significant differences between enzymatic or mechanical debridement agents with the following exceptions:Papain urea resulted in better debridement than collagenase.Calcium alginate resulted in a greater reduction in ulcer size compared to dextranomer.Adding streptokinase/streptodornase to hydrogel resulted in faster debridement.Maggot debridement resulted in more complete debridement than conventional treatment.There is limited evidence on the healing effects of debridement devices. DRESSINGS: Hydrocolloid dressing was associated with almost three-times more complete healing compared with saline gauze. There is evidence that hydrogel and hydropolymer may be associated with 50% to 70% more complete healing of pressure ulcers than hydrocolloid dressing.No statistically significant differences in complete healing were detected among other modern dressings.There is evidence that polyurethane foam dressings and hydrocellular dressings are more absorbent and easier to remove than hydrocolloid dressings in ulcers with moderate to high exudates.In deeper ulcers (stage III and IV), the use of alginate with hydrocolloid resulted in significantly greater reduction in the size of the ulcers compared to hydrocolloid alone.Studies on sustained silver-releasing dressing demonstrated a tendency for reducing the risk of infection and promoting faster healing, but the sample sizes were too small for statistical analysis or for drawing conclusions. BIOLOGICAL THERAPIES: The efficacy of platelet-derived growth factors (PDGFs), fibroblast growth factor, and granulocyte-macrophage colony stimulating factor in improving complete healing of chronic pressure ulcers has not been established.Presently only Regranex, a recombinant PDGF, has been approved by Health Canada and only for treatment of diabetic ulcers in the lower extremities.A March 2008 US Food and Drug Administration (FDA) communication reported increased deaths from cancers in people given three or more prescriptions for Regranex.Limited low-quality evidence on skin matrix and engineered skin equivalent suggests a potential role for these products in healing refractory advanced chronic pressure ulcers, but the evidence is insufficient to draw a conclusion. ADJUNCTIVE PHYSICAL THERAPY: There is evidence that electrical stimulation may result in a significantly greater reduction in the surface area and more complete healing of stage II to IV ulcers compared with sham therapy. No conclusion on the efficacy of electrotherapy can be drawn because of significant statistical heterogeneity, small sample sizes, and methodological flaws.The efficacy of other adjunctive physical therapies [electromagnetic therapy, low-level laser (LLL) therapy, ultrasound therapy, ultraviolet light therapy, and negative pressure therapy] in improving complete closure of pressure ulcers has not been established. NUTRITION THERAPY: Supplementation with 15 grams of hydrolyzed protein 3 times daily did not affect complete healing but resulted in a 2-fold improvement in Pressure Ulcer Scale for Healing (PUSH) score compared with placebo.Supplementation with 200 mg of zinc three times per day did not have any significant impact on the healing of pressure ulcers compared with a placebo.Supplementation of 500 mg ascorbic acid twice daily was associated with a significantly greater decrease in the size of the ulcer compared with a placebo but did not have any significant impact on healing when compared with supplementation of 10 mg ascorbic acid three times daily.A very high protein tube feeding (25% of energy as protein) resulted in a greater reduction in ulcer area in institutionalized tube-fed patients compared with a high protein tube feeding (16% of energy as protein).Multinutrient supplements that contain zinc, arginine, and vitamin C were associated with a greater reduction in the area of the ulcers compared with standard hospital diet or to a standard supplement without zinc, arginine, or vitamin C.Firm conclusions cannot be drawn because of methodological flaws and small sample sizes. MULTIDISCIPLINARY WOUND CARE TEAMS: The only RCT suggests that multidisciplinary wound care teams may significantly improve healing in the acute care setting in 8 weeks and may significantly shorten the length of hospitalization. However, since only an abstract is available, study biases cannot be assessed and no conclusions can be drawn on the quality of this evidence.
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Ont Health Technol Assess Ser · Jan 2009
Optical coherence tomography for age-related macular degeneration and diabetic macular edema: an evidence-based analysis.
The purpose of this evidence-based review was to examine the effectiveness and cost-effectiveness of spectral-domain (SD) optical coherence tomography (OCT) in the diagnosis and monitoring of patients with retinal disease, specifically age-related macular degeneration (AMD) and diabetic macular edema (DME). Specifically, the research question addressed was: What is the sensitivity and specificity of spectral domain OCT relative to the gold standard? ⋯ The conclusions for SD OCT based on Level 5 evidence, or expert consultation, are as follows: OCT is considered an essential part of the diagnosis and follow-up of patients with DME and AMD.OCT is adjunctive to FA for both AMD and DME but should decrease utilization of FA as a monitoring modality.OCT will result in a decline in the use of BM in the monitoring of patients with DME, given its increased accuracy and consistency.OCT is diffusing rapidly and the technology is changing. Since FA is still considered pivotal in the diagnosis and treatment of AMD and DME, and there is no common outcome against which to compare these technologies, it is unlikely that RCT evidence of efficacy for OCT will ever be forthcoming.In addition to the accuracy of OCT in the detection of disease, assessment of the clinical utility of this technology included a rapid review of treatment effects for AMD and DME. The treatment of choice for AMD is Lucentis®, with or without Avastin® and photodynamic therapy. (ABSTRACT TRUNCATED)
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Ont Health Technol Assess Ser · Jan 2009
Intraocular lenses for the treatment of age-related cataracts: an evidence-based analysis.
The objective of the report is to examine the comparative effectiveness and cost-effectiveness of various intraocular lenses (IOLs) for the treatment of age-related cataracts. ⋯ The conclusions of the systematic review of IOLs for age-related cataracts are summarized in Executive Summary Table 1. CONSIDERATIONS FOR THE ONTARIO HEALTH SYSTEM: Procedures for crystalline lens removal and IOL insertion are insured and listed in the Ontario Schedule of Benefits.If a particular lens is determined to be medically necessary for a patient, the cost of the lens is covered by the hospital budget. If the patient chooses a lens that has enhanced features, then the hospital may choose to charge an additional amount above the cost of the usual lens offered.An IOL manufacturer stated that monofocal lenses comprise approximately 95% of IOL sales in Ontario and premium lenses (e.g., multifocal/accomodative) consist of about 5% of IOL sales.A medical consultant stated that all types of lenses are currently being used in Ontario (e.g., multifocal, monofocal, accommodative, tinted, nontinted, spheric, and aspheric). Nonfoldable lenses, rarely used in routine cases, are primarily used for complicated cataract implantation situations.ES Table 1:Conclusions for the Systematic Review of IOLs for Age-Related CataractsComparisonConclusionGRADE QualityMultifocal vs. monofocalObjective OutcomesSignificant improvement in BDCUNVANo significant difference in BCDVAInconclusive evidence for contrast sensitivityInconclusive evidence for glareSubjective OutcomesInconclusive evidence for visual satisfactionSignificant increase in glare/halosSignificant increase in freedom from spectaclesmoderatemoderatelowvery lowlowlow/moderatelow/moderateAccommodative vs. multifocal/monofocalInconclusive due to Insufficient limited evidence for any effectiveness outcomevery lowHydrophilic acrylic vs. other materials (hydrophobic acrylic, silicone)Significant increase in PCO scoreLowSharp edged compared to round edgedSignificant reduction in PCO scoreLowOne piece compared to three pieceNo significant difference in PCO scorelowHydrophobic acrylic compared to siliconeNo significant difference in PCO scoremoderateAspherical modified prolate anterior surface compared to sphericalNo significant difference in VASignificant reduction in contrast sensitivityvery lowvery lowBlue light filtering compared to non blue-light filteringNo significant difference in BCDVANo significant difference in contrast sensitivityNo significant difference in HRQLlowlowhigh/moderateBCDVA refers to best corrected distance visual acuity; BDCUNVA, best distance corrected unaided near visual acuity; HRQL, health related quality of life; PCO, posterior capsule opacification; VA, visual acuity.
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Ont Health Technol Assess Ser · Jan 2009
Oral appliances for obstructive sleep apnea: an evidence-based analysis.
The objective of this review was to determine the clinical effectiveness of oral appliances compared to 'no treatment', continuous positive airway pressure (CPAP), or surgery for the management of obstructive sleep apnea (OSA). ⋯ Obstructive sleep apnea, oral appliances, mandibular advancement splints, tongue repositioning devices.
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Ont Health Technol Assess Ser · Jan 2009
Fenestrated endovascular grafts for the repair of juxtarenal aortic aneurysms: an evidence-based analysis.
Endovascular repair of abdominal aortic aneurysm (AAA) allows the exclusion of the dilated aneurismal segment of the aorta from the systematic circulation. The procedure requires, however, that the endograft extends to the healthy parts of the aorta above and below the aneurysm, yet the neck of a juxtarenal aortic aneurysm (JRA) is too short for a standard endovascular repair. Fenestrated endovascular aortic repair (f-EVAR) provides a solution to overcome this problem by enabling the continuation of blood flow to the renal and visceral arteries through holes or 'fenestrations' in the graft. These fenestrations are designed to match the ostial diameter of the renal and visceral arteries.There are three varieties fenestration, small, large, and scallop, and their location needs to be customized to fit the anatomy of the patient. If the device is not properly designed, if the alignment is inaccurate, or if the catheterization of the visceral arteries is not possible, the procedure may fail. In such cases, conversion to open surgery may become the only option as fenestrated endografts are not retrievable.It is recommended that a stent be placed within each small fenestration to the target artery to prevent shuttering of the artery or occlusion. Many authors have noted an increased risk of vessel occlusion in unstented fenestrations and scallops.Once placed in a patient, life-long follow-up at regular intervals is necessary to ensure the graft remains in its intended location, and that the components have adequate overlap. Should the need arise, routine follow-up allows the performance of timely and appropriate intervention through detection of events that could impact the long-term outcomes. ⋯ f-EVAR Studies versus OSR StudiesTechniqueNumber ofPatientsMean Age(Range), YearsAneurysm Diameter(Range),mmMean Duration ofFollow-up, Yearsf-EVAR(5 studies)27474 (72-75)63 (59-68)9.4-25.8OSR(7 studies)856:JRA: 675SRA: 136TAA: 4572 (67-78)62 (50-70)1-48JRA, Juxtarenal aortic aneurysm; SRA, Suprarenal aortic aneurysm; TAA, Thoracic aortic aneurysm MORTALITY OUTCOMES: The pooled estimate for 30-day mortality was 1.8% among the f-EVAR studies and 3.1% among the OSR studies that reported data for the repair of JRA separately. The pooled estimate for late mortality was 12.8% among the f-EVAR studies and 23.7% among the OSR studies that reported data for JRA separately. VISCERAL ARTERY EVENTS REPORTED IN F#ENTITYSTARTX02014;EVAR STUDIES: RENAL EVENTS DURING F-EVAR: A total of three main renal arteries and two accessory renal arteries became occluded during the procedure. These were all due to technical issues, except one accessory renal artery in which the artery was intentionally covered. One patient required open surgery following the procedure. RENAL EVENTS DURING THE FOLLOW-UP: A total of 12 renal arteries (12 patients) were found to be occluded during follow-up. In two patients, the same side accessory renal artery was also occluded. Four (1.5%) patients lost one kidney and five (2.3%) patients underwent dialysis, three (1.4%) of which became permanent. A total of 16 cases of renal artery stenosis (16 patients) occurred during follow-up. Eight of these were treated and eight were observed. Segmental renal infarcts were found in six patients but renal function was not impaired. MESENTERIC EVENTS DURING F-EVAR: Three mesenteric events occurred during the f-EVAR procedures resulting in two deaths. One patient developed bowel ischemia due to embolization of the superior mesenteric artery (SMA); this patient died 13 days after the procedure from multiorgan failure. One patient died eights days after the procedure from mesenteric ischemia and bowel perforation. The third SMA event occurred during surgery with subsequent occlusion in early follow-up. MESENTERIC EVENTS DURING FOLLOW-UP: During follow-up, five (1.8%) SMA occlusions/partial occlusions and one SMA stenosis were noted. Three of the five patients with SMA occlusion/partial occlusion remained asymptomatic and no further intervention was necessary. One patient underwent SMA bypass surgery and in two patients, the problem solved by SMA stenting. A summary of the outcomes reported in the f-EVAR and OSR studies is shown in Table ES-2. ES-2.Summary of Outcomes: Fenestrated Endovascular Graft Versus Open Surgical Repair for Treatment of Juxtarenal Aortic AneurysmOutcomef-EVAROSRPooled Estimate (Rate)30-day mortality1.83.1Late mortality12.823.7Permanent dialysis0-2.50-3.5Loss of kidney1.5No report of kidney loss Incidence of post-op renal insufficiency: 14.4%Mesentric ischemia3.32.9Aortic rupture00Post-op cardiac complications1.510.7Post-op pulmonary complications0.713.4Post-op GI complications0.75.9Aneurysm expansion1.40Secondary intervention (Non-endoleak)8.87.8EndoleakType I: 4Type 2: 16.8Type III: 1.8N/AEndoleak required treatmentType I: 2.9Type 2: 3.3Type III: 1.1Graft migration1.5N/AGraft separation0.7Duration (Mean)Operation time (min)240287Hospital stay (days)613 SUMMARY: Short- and medium-term results (up to 2 years) of f-EVAR for the repair of JRA showed that outcomes in f-EVAR series compare favourably with the figures for the OSR series; however, uncertainty remains regarding the long-term results. The following observations are based on low quality evidence. F-EVAR has lower 30-day mortality than OSR (1.8% vs. 3.1%) and a lower late-mortality over the period of time that patients have been followed (12.8% vs. 23.7%).There is a potential for the loss of target vessels during or after f-EVAR procedures. Loss of a target vessel may lead to loss of its respective end organ. The risk associated with this technique is mainly due to branch vessel ischemia or occlusion (primarily among the renal arteries and SMA). Ischemia or occlusion of these arteries can occur during surgery due to technical failure and/or embolization or it may occur during follow-up due to graft complications such as graft migration, component separation, or arterial thrombosis. The risk of kidney loss in this series of f-EVAR studies was 1.5% and the risk of mesenteric ischemia was 3.3%. In the OSR studies, the risk of developing renal insufficiency was 14.4% and the risk of mesenteric ischemia was 2.9%.F-EVAR has a lower rate of postoperative cardiac and pulmonary complications.Endoleak occurs in 22.5% of patients undergoing f-EVAR (all types) and about 8% of these require treatment. Most of the interventions performed to treat such endoleaks conducted using a minimally invasive approach.Due to the complexity of the technique, patients must be appropriately selected for f-EVAR, the procedure performed by highly experienced operators, and in centers with advanced, high-resolution imaging systems to minimize the risk of complications.Graft fenestrations have to be custom designed for each patient to fit and match the anatomy of their visceral arteries. Planning and sizing thus requires scrutiny of the target vessels with a high degree precision. This is important not only to prevent end organ ischemia and infarction, but to avoid prolonging procedures and subsequent adverse outcomes.Assuming the average cost range of FEVAR procedure is $24,395-$30,070 as per hospital data and assuming the maximum number of annual cases in Ontario is 116, the average estimated cost impact range to the province for FEVAR procedures is $2.83M-$3.49M annually.