How to reduce the incidence of lower extermity amputations in diabetes with Hyperbaric oxygen (HBO) therapy - Literature review Example

?How to reduce the incidence of lower extermity amputations in diabetes with Hyperbaric oxygen therapy (HBOT)? Introduction Hyperbaric oxygen therapy(HBOT) is a popular treatment method for decompression sickness (also known as the caisson disease, diver’s disease or the bends). It utilizes a special sealed chamber which is pressurized up to three (3) times the normal atmospheric pressure (Zieve & Hadjiliadis 2012). Inside the chamber the patient can breathe pure oxygen, hence effectively increasing the amount of oxygen in the blood. Over the years, HBOT has been used to treat various illnesses including gas embolism, gas gangrene, skin grafts, bone infections and many others (Zieve & Hadjiliadis 2012). While HBOT has been used to treat many conditions, there is still conflicting evidence as to its effectiveness in treating infections of the skin and tissues. In response to the growing need for evidence that proves the value of HBOT, this study focuses on previous literature which utilized the HBOT in treating diabetic wounds and ulcers. At the end of this paper, we hope to address the question: Is hyperbaric oxygen therapy effective at reducing the incidence of lower extremity amputations among diabetic patients? In a research by Meryl Brod (1997) it was mentioned, “Lower extremity ulcers are among the most common and costly complications of diabetes. They are a leading cause of amputation and account for more hospital days than other diabetic complications” (627). Aside from its economic cost, diabetic ulcers has a negative impact on a person’s quality of life; thereby making treatment for lower extremity ulcers a priority for many health care practitioners. Having said this, it is now important to qualify that this critical appraisal isn’t really about preventing amputations among diabetic patients, but rather, finding an effective treatment to cure foot ulcers. Search Methods and Identification of Studies To address the question posed in the introduction of this paper, the researcher searched two databases, PubMed and Google Scholar. The search terms used were hyperbaric oxygen therapy, curing diabetic ulcers, preventing diabetic amputations, hyperbaric oxygen therapy and diabetes, and effectiveness of hyperbaric oxygen in curing diabetic wounds. Thousands of resources were returned so several criteria for inclusion was created. Resources were accepted or rejected based on the following criteria: (1) the study cover the treatment for diabetes wounds and ulcers (2) the study must not be older than 1995; (3) the study must be in English; (4) the study must involve human subjects. Accepted resources were subjected to an ancestry search of their references to discover new resources which can be used to address the clinical question. Ten (10) studies were then included at the end of this search. The resources are intentionally international in scope in order to determine what factors may affect the efficacy of HBOT in treating lower extremity wounds and ulcers. Method for Appraising Articles For the purpose of this study, methodology for rapid critical appraisal (RCA) will be utilized. Through the RCA, this critical appraisal paper will review each study in order to determine (1) its level of evidence, (2) how well it was conducted, and (3) how useful it is to practice (Fineout-Overholt et al. 2010). Results Determining the Level of Evidence To determine the level of evidence, studies were classified according to their design. Using the “Hierarchy of Evidence for Interventions Studies” by Ellen Fineout-Overholt et al. (2010) was used. In this case, six of the studies were identified as meta-analyses or systematic review of random controlled trials (Level 1 evidence), two were randomized controlled trials (Level 2), one is a cohort study (Level 4), one is a case-control study (Level 4). Note that those researches with Level 1 evidence are most reliable and they provide the best evidence to answer the clinical question (Fineout-Overholt et al. 2010). From this first phase, one can already see that the studies are quantitative in nature and were somewhat reliable. Of course, to determine the studies’ validity and value for the practice, one must follow the “Critical Appraisal Guide for Quantitative Studies” by Fineout-Overholt et al. (2010). Appraising the Articles This critical appraisal guide had (7) questions. These are (Fineout-Overholt et al. 2010): (1) Why was the study done? (2) What is the sample size? (3) Are the instruments of the major variables valid and reliable? (4) How were the data analyzed? (5) Were there any untoward incidents during the study? (6) How do the results fit previous research in the area? (7) What does this research mean for clinical practice? Eight of the ten articles reviewed for this paper dealt specifically with the effect of HBOT to diabetic foot ulcers (DFU). All of them found that HBOT is effective in healing DFU but not all of them dealt directly with lower extremity amputations. Canadian Diabetes Association Technical Review: The Diabetic Foot And Hyperbaric Oxygen Therapy. Agnes Rakel, Celine Huot and Jean Marie Ekoe (2006) is a systematic review (SR) of literature of the topic. Unlike the other SR, this article included both random and non-random controlled trials. Working with eight studies, Rakel et al. (2006) utilized the Wagner’s classification for foot ulcers and reduction risk for major amputation or RR (rate at which major amputations are avoided) to determine the effectiveness of HBOT in treating DFU. The results show that patients had to undergo 34 HBOT sessions on the average. Rakel et al. (2006) discovered that HBOT treatments tend to hasten the healing time of wounds. RR for five of the eight studies had an average of 90%, which is significant. While the results of this article supported the claim that HBOT prevents lower extremity amputations, the supporting evidence found on the article cannot justify this. Moreover, the paper did not outline its criteria for including articles in the review and it id not employ any method to judge the validity of the studies included. Because of these, the SR’s validity are also called into question. Despite the weak results of the study, its contribution to practice relies on the issues it raised about HBOT side effects and why the should be written in the reports of controlled trials. Cost-effectiveness and budget impact of adjunctive hyperbaric oxygen therapy for diabetic foot ulcers. This second article by Chuck Anderson, David Hailey, Philip Jacob and Douglas Perry (2008) also tried to determine the effect of HBOT to DFU. Aside from an SR, the study performed a cost-utility analysis to determine whether HBOT is cost-effective. The authors reported that they searched 12 databases and 5 journal websites to discover articles for this study. To be included in the review, studies had to be reports of controlled trials where patients were treated with adjunctive HBOT and standard care. This study corroborated the results of Raket et al., but more importantly, it has discovered that HBOT is a cost-effective form of treatment for DFU. Moreover, by using HBOT, the study found that a patient’s quality of life can increase by at least 0.50 years. Anderson et al. (2008) estimated that the government will need to allot atleast CAD$14.4 to 19.7 million to cure all prevalent DFU cases in four years. Note that this study did not dwell with LEA so it cannot answer the posted clinical question but its results are important in deciding the importance of utilizing HBOT during treatment. Hyperbaric oxygen therapy: solution for difficult to heal acute wounds? Systematic review. This next article deals with HBOT as treatment for various types of wounds. It does not deal directly with diabetic wounds but its results show important points that can help answer the clinical question. For one, the results of the study shows that HBOT is most effective at improving the healing time of large chronic wounds such as crush injuries and split skin grafts. According to the authors, in the case of ischemic wounds such as diabetic ulcers, HBOT can help over an initial period of local ischema which is the cause of the problematic healing (Eskes et al. 2011). This study explicitly states that HBOT cannot be used as standard care for large, chronic wounds despite its effectiveness because it is not yet cost-effective and the equipments needed are ot readily available. Hyperbaric oxygen therapy for chronic wounds. Of all the studies reviewed in this paper, Peter Kranke et al. (2004) probably had the strongest study design. Utilizing five randomly-assgined controlled studies, the study discovered that wound reduction for diabetic ulcers can occur on the 6th to 8th week of treatment, but healing rate for subsequent ulcers can be affected a year after the therapy. RR for this data was also at 0.31% and number needed to treat (NNT) is four. This (NNT) means that found every four patients treated with HBOT, one of them is prevented from undergoing a major LEA. It has expanded the results of the first study by Rakel et al. and made the result more practical. It is also the first time that the cumulative nature of HHBOT is discussed Perhaps one strength Kranke et al.’s article is that it utilized the Cochrane to assess the validity of the studies it reviewed. Cost-effectiveness of hyperbaric oxygen in the treatmet of diabetic ulcers. This study by Shien Guo et al (2004)is a cohort study of 1,000 patients with Wagner III or above rating, over a period of 35 years. It utilized public health data from 1965 to 2000 and a 1995 study by the Hyperbaric Oxygen Treatment Association to get HBOT and standard care costs. To get healing rate of diabetic ulcers and LEA rates, Guo et al. searched MedLine for studies. To be included in this study, resources had to be of prospective controlled design and must have a diabetic etiology. Of all the studies reviewed, Guo et al. provided one of the most comprehensive results. For example, it reported that patients who have undergone adjunctive HBOT had an mean HR of 55% compared to only 33% to those who opted for standard treatment. Moreover, rate of major LEA for groups with HBOT is 35% compared to 41% to those without HBOT. The study also used the EQ 5D indicator to test for sensitivity. The results of this sensitivity analysis shows that 165 major LEAs were aborted while a total of 608.7 Quality-of-Life-Adjusted Years (QALY) was gained during the 12 years of study because of HBOT use. Further analysis showed that a total of $1.77 million due to minor LEA and $6.30 million due to major LEA was saved, thanks to the use of HBOT I treating diabetic ulcers. Guo et al. (2004) also calculated the incremental cost of using HBOT for 12 years which amounts to $2,255. Guo et al.’s study is a good source for organizations wishing to redesigning treatment plan for diabetics. The role of hyperbaric oxygen therapy in ischaemic diabetic lower extremity ulcers: a double-blind randomised-controlled trial. This article by A. Abidia et al. (2003) is probably the most reliable of all reviewed research because it is the only one that utilized a random-controlled controlled trail, double blind design. Aside from discovering the effectiveness of HBOT for DFUs, this study also attempted to discover how treatment affects a person’s quality of life. Like the other researches, Abidia et al. (2003) found that HBOT was highly effective with 100% of diabetic wounds have shown signs of healing after only 6 weeks. Yet, the more important part of this study is its use of the HAD score which is a measure of quality of life among hospitalized individuals. HAD score for both the treatment and control group increased, with general health and vitality at high levels. This result has signified the importance of providing treatment to diabetic patients, particularly in the healing of wounds which might have caused them insecurity and hopelessness in the past. The authors said that by using HBOT as adjunct treatment, potential savings is computed at ?2960 at the minimum. A systematic review of foot ulcer in patients with Type 2 diabetes mellitus. II: treatment. This next article is a review of literature on the various methods of treating foot ulcers of patients with type 2 diabetes. Of the SRs reviewed in this paper, this study by Jason Mason et al. (1999) included the most number of resources (29 in total), all of them are random controlled trials (RCT). This study in study included four RCTs on antibiotic therapy, ten on dressings and topical creams, two RCTs on cultured human dermis, two RCTs involving HBOT, one on casting, two on ketanerin, six on growth factors, one of educations of patients with DFU and one RCT on granulocyte-colony. Because each of the studies utilized different indicators, there was no way to check which of the various DFU treatments was the most effective. Hence, the focus was on the two RCTs for HBOT. According to Mason et al. (1999) rate of LEA for patients using HBOT is lower at 8.6% while those who do not use HBOT has LEA at 33%. This article is important because it shows the other forms of DFIU and it recognizes the potential of HBOT despite the existence of other alternatives. As has been discussed in the paper, healing time of DFU treated with HBOT can be affected by the severity of the ulcers. Moreover, it showed that there are many ways of doing HBOT and that there is a need to determine the right amount of pressure and method of delivery that works best for this purpose. For a more complete listing of the critical appraisal, please refer to the Appendix. Discussion of the Results Except for one study (Medical Advisory Secretariat 2005), all reviewed resources showed that HBOT was a superior form of treatment for individuals with diabetic foot ulcers (DFU) or lower extremity ulcers (LEU). Effectiveness of HBOT was typically measured by the healing rate (number of ulcers healed after a period of time), and the reduction of risk for lower extremity amputations (LEA). Studies have different data on LEA and healing rate, depending on the followup period. Most of the studies aimed to discover the effectiveness of HBOT as treatment for diabetic foot ulcers (DFU) and lower extremity ulcers (LEU) compared to standard care. Note however that “standard care” differs for every research, sometimes it referred to dressings, sometimes its meaning is not even reported. For most of the studies, healing rate (wound size reduction) and amputation avoidance were used as indicators of HBOT effectiveness. While some studies did not articulate their methodology (Rakel et al. 2006), an others which did not perform meta-analyses of the data they have gathered, each one of the studies reviewed revealed new information that extended out knowledge of HBOT. For example, Chuck et al. (2008) showed that HBOT use improves a person’s quality-adjusted life-years, while Abidia et al. (2003) talked about the connection between HBOT and a patient’s quality of life. Meanwhile, Guo et al. (2004) provided proof that aside from HBOT’s effectiveness at treating DFUs, it was also cost-effective. Three studies (Londahl et al. 2010; Ong 2008; Mason et al. 1999; Eskes et al. 2011) showed that there are other factors (i.e. size of wound, incidence of amputation before treatment, age and initial health status of patient, etc.) that affect the effectiveness of HBOT. It is important to study these factors so as to truly determine whether it was HBOT that promoted wound healing. This critical appraisal discovered that HBOT is most effective for treating large, chronic wounds, but it can take a long time to take effect. In the study by Kranke et al. (2004), it took one (1) year before healing started. The good news is that once the treatment takes effect, healing rate is high, as much as 89% for some studies (Guo et al. 2004). Moreover, the risk for major lower extremity amputation (LEA) can decrease as much as 95% (Rakel et al. 2006) with adjunctive HBOT. While Abidia et al. (2003) showed that HBOT is no cost-advantage compared to standard care, Guo et al. (2004), proved in their study that the treatment is more effective in the long run, averting more than $8 million in costs for major and minor LEA. The studies appraised in this paper had varying degree of validity and reliability. For example in the study by the Medical Advisory Secretariat (2005) it showed that many systematic reviews of HBOT use are of low quality, hence there is a need to review the methodologies they use. Conclusion Based on the researches appraised in this paper, it can be seen that the adjunctive HBOT is effective at reducing the probability of LEA. Note however that HBOT cannot be used as an emergency intervention for individuals suffering from extreme LEU. Instead, it is best used for patients whose skin lesions are only at Wagner III to VI. Moreover, because its effects are cumulative, one cannot expect immediate effects for this, and will need to wait for at least a year before it registers physiological changes. It is also important to note that HBOT has been utilized as an adjunctive treatment option, which means it has never been tested on its own. As such, it cannot be used as standard treatment as most patients will want to be relieved from the pain of the LEU immediately. At a time when HBOT equipments are still limited, treatments are still expensive, and might not be covered by health insurance. Because of this, patients who wish to avail of this treatment have to pay out of their pockets – which can be a problem if the patient has limited financial capabilities. Having said that, it becomes apparent why, despite the high effectiveness of HBOT, it is not used as standard care for LEU. Bibliographyhttp://cdn.intechopen.com/pdfs/18923/InTech-Hyperbaric_oxygen_therapy_in_the_treatment_of_necrosis_and_gangrene.pdf Abidia, A. et al., 2003. The role of hyperbaric oxygen therapy in ischaemic diabetic lower extremity ulcers: a double-blind randomised-controlled trial. European Journal of Vascular and Endovascular Surgery, 25(6), p.513-518. Available at: http://hyperbaricinformation.com/HBO-Articles/HBO-Hypoxic-Wounds/EJVES-25-513-2003-Abidia-HBO-DFU.pdf [Accessed April 1, 2012]. Anderson, C. et al., 2008. Cost-effectiveness and budget impact of adjunctive hyperbaric oxygen therapy for diabetic foot ulcers. International journal of technology assessment in health care, 24(2), p.178-83. Available at: http://www.ncbi.nlm.nih.gov/pubmed/18400121 [Accessed April 1, 2012]. Brod, M., 1997. Quality of life issues in diabetic patients with lower extremity ulcers and their care givers. Quality of Life Research: The Improvement of Quality of Life: A Purpose of Health Care: Abstracts: 4th Annual Conference of the International Society for Quality of Life Research, 6(7/8), p.627. Eskes, A.M. et al., 2011. Hyperbaric oxygen therapy: solution for difficult to heal acute wounds? Systematic review. World journal of surgery, 35(3), p.535-42. Available at: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=3032900&tool=pmcentrez&rendertype=abstract [Accessed April 4, 2012]. Fineout-Overholt, E. et al., 2010. Evidence-based practice step by step: Critical appraisal of the evidence: part I. The American journal of nursing, 110(7), p.47-52. Available at: http://www.ncbi.nlm.nih.gov/pubmed/20574204 [Accessed April 3, 2012]. Guo, S. et al., 2004. Cost-effectiveness of hyperbaric oxygen in the treatmet of diabetic ulcers. International Journal of Technology Assessment in Health Care, 19(04). Available at: http://www.journals.cambridge.org/abstract_S0266462303000710 [Accessed April 4, 2012]. Kranke, P. et al., 2004. Hyperbaric oxygen therapy for chronic wounds. Cochrane database of systematic reviews (Online), (2), p.CD004123. Available at: http://www.ncbi.nlm.nih.gov/pubmed/15106239 [Accessed April 4, 2012]. Londahl, M. et al., 2010. Hyperbaric oxygen therapy facilitates healing of chronic foot ulcers in patients with diabetes. Diabetes care, 33(5), p.998-1003. Available at: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2858204&tool=pmcentrez&rendertype=abstract [Accessed March 12, 2012]. Mason, J. et al., 1999. A systematic review of foot ulcer in patients with Type 2 diabetes mellitus. II: treatment. Diabetic Medicine, 16(11), p.889-909. Medical Advisory Secretariat, 2005. Hyperbaric oxygen therapy for non-healing ulcers in diabetes mellitus. Ontario Health Technology Assessment Series, 5(11). Available at: http://www.health.gov.on.ca/english/providers/program/mas/tech/reviews/pdf/rev_hypox_081105.pdf. Ong, M., 2008. Hyperbaric oxygen therapy in the management of diabetic lower limb wounds. Singapore Medical Journal, 49(2), p.105-109. Rakel, A., Huot, C. & Ekoe, J.-M., 2006. Canadian Diabetes Association technical review:the diabetic foot and hyperbaric oxygen therapy. Canadian Journal of Diabetes, 30(4), p.411-421. Available at: http://www.diabetes.ca/files/huotnov282006.pdf. Zieve, D. & Hadjiliadis, D., 2012. Hyperbaric oxygen therapy. Medline Plus. Available at: http://www.nlm.nih.gov/medlineplus/ency/article/002375.htm [Accessed April 1, 2012]. Read More