Costing report for a new diagnostic test for the detection of acute compartment syndrome.

Transcription

1 Costing report for a new diagnostic test for the detection of acute compartment syndrome. Report detailing the estimated cost implications to the UK health services of adopting a new diagnostic tool for the identification and thus the timely treatment of acute compartment syndrome, an example applied to the case of tibial fractures. Prepared by: Dwayne Boyers Contact: Dwayne Boyers, Health Economics Research Unit Health Services Research Unit University of Aberdeen, UK Tel: ; d.boyers@abdn.ac.uk May 22 nd 2012 This document was prepared by a researcher working at The Health Economics (HERU) and Health Services Research Units (HSRU) at the University of Aberdeen. HERU and HSRU are funded by the Chief Scientist s Office (CSO) of the Scottish government. The views expressed in this report are those of the authors and not necessarily HERU, HSRU or CSO. All errors and omissions are the responsibility of the authors.

2 P a g e 1 Background: Acute Compartment Syndrome (ACS) is an under diagnosed problem that occurs when pressure within fibrous compartments (that include groups of muscles and nerves) and within the muscles themselves builds to dangerous levels. This pressure rise results in a decrease in blood flow, which prevents oxygen and other nutrients from reaching the already traumatised and increasingly susceptible nerve and muscle cells, resulting in tissue death. ACS is painful and on occasions limb and life threatening, occurring most often after fractures or soft tissue crushing injuries of the forearm and lower leg. The most clearly defined and researched case is compartment syndrome occurring after tibial shaft (diaphyseal) fractures. The earlier a definitive diagnosis can be made, the earlier contingency measures can be taken and appropriate treatment procedures initiated, thus reducing the amount of permanent muscle and nerve damage, and increasing the chances of avoiding longer term complications, the need for limb salvage or amputation, and in extreme cases, death. Costing Methods: The following piece of work aims to quantify the potential costs of acute compartment syndrome (at various stages of diagnosis). This example of costing is applied to the case of tibial shaft fractures. We compare resource use and costs of the current best practice diagnostic strategy (pressure monitoring) with those for diagnosis with the new proposed ph probe system. Based upon the results of clinical research, it is envisaged that the technology being presented will allow earlier diagnosis, thereby increasing the number of potential ACS patients being diagnosed earlier, and thus incurring fewer complications and less health care resource use consumption. We have conducted a relatively simple costing analysis to give an indication of the magnitude of cost implications. Estimates of health care resource use over the first year after diagnosis are taken from a clinical expert opinion 1 and the scenarios presented are a guideline of potential resource use at 5 stages of diagnosis ranging from earliest to latest and missed diagnosis for scenarios 1-5 respectively (table 1 and appendix A1-A5). Costs are applied to these estimates of resource use, using standard national average costing sources where possible. These are applied as follows: Inpatient care (Information Services Division (ISD) Scotland 2 ), outpatient care (ISD Scotland 2 ), Primary care (Personal Social Services Research Unit (PSSRU), Curtis, ), re-operations over the course of 1 year (Information Services Division (ISD) Scotland 2 ). These form the main proportion of costs incurred by the health services. Additional component costs of prosthetics and equipment are sourced locally from the Mobility and Rehabilitation Services at Woodend Hospital, Aberdeen. For inpatient care, we have elected to use a bottom up costing approach, based on estimated time in

3 P a g e 2 theatre for various procedures, combined with the estimated length of stay on the hospital ward. An alternative option may have been to use national average unit costs for various procedures. However, we have chosen a bottom up approach as Health Research Group (HRG) codes are not sufficiently sensitive to capture differences in the procedures we are interested in. Despite the potentially large resource impact, HRG unit costs for surgery may not be appropriate as all variations may fall within one wide bracket of care, and so would not be an appropriate fit to the scenarios we are interested in. The inappropriateness of HRG unit costs to this scenario is in part due to the exploratory nature of scenarios 1 and 2 presented (See appendix tables A1&A2), and as such no relevant HRG exists. It is the author s view that the costing method used for this analysis is the most appropriate and accurate reflection of the decision problem presented in this document. Our costing analysis is from the perspective of the NHS, and can be adapted to suit any health care decision maker s needs. Costs are presented in UK pounds sterling, 2010, unless otherwise stated. Where costs are presented in a different currency, these are translated using standard exchange rates, (e.g. 1USD = 0.63GBP). Table 1 outlines the cost implications on a per patient basis for the first year after diagnosis of 5 potential strategies of care which the patient may require. Which stage a patient falls into is based predominantly on how early an accurate diagnosis of ACS is made. A detailed breakdown of resource use and costing calculations for each scenario are presented in appendices to this report. While resource use estimates are based on clinical expert opinion at one particular hospital 1, it is unlikely that practice would differ significantly across the UK, and indeed our resource use estimates are likely to be generalisable across many countries. Costs are then extrapolated to the general UK population (See table 2) using published estimates of tibial shaft fractures and acute compartment syndrome. Cost estimates are based on costs incurred over the first year after diagnosis. The justification for this is that it is over the first year when the most significant health care resources will be incurred. The relative diagnostic costs of the proposed and current kits are considered in table 2, taking account of the number of tests required to achieve a positive diagnosis (i.e. testing all tibial shaft fractures in the UK). Due to the uncertainty in our estimates, key assumptions regarding costs are tested in sensitivity analysis (table 3). We also test a scenario where stage 1 is neither realistic nor achievable by any currently available diagnostic tools, or indeed the new technology being proposed. These analyses are not necessarily intended to be likely scenarios of care, but rather an illustration of the sensitivity of our results to the assumptions we have made. Additional estimates for lifetime costs of amputation and limb salvage and the potential costs of litigation are commented on in the discussion section.

4 P a g e 3 Results: The proposed cost of the diagnostic probe is expected to be approximately 150 per test once development is complete and the probe is in routine use in the NHS. The current cost in a research setting is about 300 per test. Should the test be manufactured widely for use in the NHS, the manufacturer will avail of substantial economies of scale, hence the lower unit cost of 150 per test. We have taken a pragmatic approach and used this as our base case cost, considering a higher cost of 300 per test in sensitivity analysis. The cost of the current best practice diagnostic tool is approximately 50 per test 1. This is described elsewhere, but in brief, current best practice uses pressure measurements as opposed to a ph system to detect compartment syndrome. As the ph system tool is more reactive than the currently used pressure systems, it becomes possible to make a diagnosis earlier, before muscle damage occurs or by limiting the extent of muscle damage. This of course assumes that the patient presents at the Accident and Emergency department in a timely manner. These additional diagnostic costs must be considered in the broader context of costs to the health services, namely surgical costs and costs of following patients over an extended time period. We explicitly model costs over one year, but acknowledge the likely longer-term cost implications also, in terms of continued care requirements, especially for those receiving amputations. Scenarios 1 and 2 represent the benefits of earlier stage diagnosis, while scenario 3 represents current practice. For example, if a patient presents early to Accident and Emergency and thus the hospital, these scenarios represent potential savings from using a faster and more efficient diagnostic tool. The analyses presented here assume that sensitivity and specificity of the proposed diagnostic probe are equal to one (i.e. the new test would generate no false positive or false negative results). This is based on current research observations, however, would require formal research to definitively prove this statement correct. Scenarios 4 and 5 on the other hand represent the more extreme cases that require limb salvage and / or amputation. It is anticipated that when patients present late to the emergency room (e.g. after serious road traffic collisions where time to hospital is reduced due to extraction difficulties), the new diagnostic tool may allow a more rapid diagnosis, keeping a greater proportion of patients in scenario 3 as opposed to 4 or even 5.

5 P a g e 4 Table 1: Summary of costing scenarios considered. Scenario Description Total cost to health services (first year post diagnosis) ( ) Scenario 1: Earliest possible diagnosis no significant muscle damage 4,690 Scenario 2: Appropriate diagnosis with moderate muscle damage 11,559 Scenario 3: Current practice late but correct diagnosis 17,064 Scenario 4: Missed acute compartment syndrome. (Limb salvage) 36,787 Scenario 5: Missed acute compartment syndrome (Limb amputation required) 40,360 The incidence of tibial fractures (open and closed) in the UK has been estimated at about 23/100,000 per year of the general population 4. Assuming a UK population of about 63 million 5, this would equate to a total of 14,490 cases in the UK annually. Sensitivity analysis explores the impact on our results of using a high (30/100,000) and a low incidence (17/100,000) of tibial shaft fractures. There is much uncertainty in the literature regarding the incidence of compartment syndrome among tibial shaft fracture patients, with one review quoting an incidence of up to 30.4% 6. Another source suggests about 20% 7. We have taken a conservative estimate of 15% for our base case analysis, and explore lower and higher proportions of 5% and 30% respectively. Of those 14,490 tibial fractures, an estimate of 15% equates to 2,174 cases of compartment syndrome after tibial fractures in the UK annually. However, this is likely to be an underestimate of the true incidence of ACS, as current diagnostic systems are only about 65% accurate 1. Therefore the true number of ACS for tibial shaft fractures is potentially greater than reported in the literature. It is estimated that about 10% of all ACS cases of tibial fracture 1 will progress to stages 4/5 using current systems (i.e. these cases will be diagnosed too late to prevent amputation or limb salvage). The proposed diagnostic test is assumed to be 100% sensitive and will pick up all these cases earlier, thus preventing the need for amputation / salvage due to compartment syndrome in those presenting to the ward in a timely manner after injury. Based on these figures, 217 cases will unnecessarily progress to stages 4 or 5 as a result of failures of current systems. Assuming a 60/40 split between salvage and amputation for the serious missed cases, 130 / 87 cases will go to scenarios 4 and 5 respectively. It is assumed that the probe will identify all potential cases. It is assumed that those currently at stages 4 or 5, will be captured at stage 3 using the new technology, with the remaining cases split evenly between stages 1 and 2. The division of cases of ACS among

6 P a g e 5 the 5 stages outlined are sourced from clinical expert opinion 1. Our costing and probabilities are based on the strong assumption that all patients will arrive at the emergency room in time for an ontime diagnosis to be possible. Sensitivity analysis tests the impact of these strong assumptions on our results (See Table 3). Using the assumed number of UK cases of tibial shaft fractures and acute compartment syndrome, we have developed an estimated cost to the UK health services over the first year of treatment (See Table 2). It is assumed that the majority of costs to the health services occur over this time period. However, it is important to note, that lifelong costs of amputation and limb salvage are significant and should also be considered as an important factor and these are considered in the discussion section. Table 2: Estimated potential cost savings of adopting new strategy. Current care pathway Proposed care pathway (N=1350) (N=1350) N Unit cost ( )* Total cost ( )* N Unit cost ( )* Total cost ( )* Intervention 14, ,500 14, ,173,500 Estimate cost difference ( )* Stage 1 0 4, ,690 4,586,820 Stage , ,559 11,304,702 Stage ,064 33,377, ,064 3,702,888 Stage ,787 4,782, ,787 0 Stage ,360 3,511, ,360 0 Total cost 42,395,314 21,767,910 20,627,404 *costs rounded to the nearest whole. We have adopted a conservative approach to our costing method, due to the high level of uncertainty, and the requirement for further research into the use of this technology. Table 3 shows a range of sensitivity analyses designed to explore uncertainty in our estimates.

7 P a g e 6 Table 3: Sensitivity analysis around cost estimates Analysis Current ( ) Proposed ( ) Difference ( ) Base case costs: 42,395,314 21,767,910 20,627,404 Assume no additional patients could be prevented going to stages 4/5 with the probe. (I.e. all would be captured at stage 3, regardless of technology used). Assume stage 1 would never be achievable with the probe 37,804,572 19,828,039 17,976,534 42,395,314 28,485,792 13,909,522 Cost of the new diagnostic test will not 42,395,314 23,941,410 18,453,904 reduce to 150 per test and will remain at 300, the research cost of the probe. (unlikely but possible) Low incidence of tibial fractures (17/100k) 31,324,636 16,084,767 15,239,869 High incidence of tibial fractures (30/100k) 55,306,798 28,397,836 26,908,962 Low incidence of ACS (5%) 14,602,509 8,699,282 5,903,227 High incidence of ACS (30%) 84,102,915 41,379,384 42,723,531 The results in Table 3 show substantial differences in the potential cost savings, however, all cases suggest that the ph probe system is cost saving to a health care provider. In particular, analyses 5-8 demonstrate the impact of uncertainty in incidence rates on our results. We can conclude that the incidence of ACS among tibial shaft fracture cases is a key driver of the magnitude of potential cost savings, ranging from savings of 5.9m to 42.7m for incidences of 5% and 30% respectively. A threshold analysis indicates that, all else held constant, based on our calculations and assumptions, the true incidence of ACS would be required to be about 1% of all tibial shaft fractures before our model predicts additional cost to the NHS of adopting the new test. Therefore, if the most plausible estimate is >1%, it is likely that the new probe is cost saving. This is because the additional costs of the proposed test are small in magnitude compared to the substantial cost savings generated by an earlier diagnosis. As discussed, the results remain uncertain and open to potential biases as these estimates are not based on published sources. However, there appears (based on the assumptions made) a potential for significant cost savings by utilising this technology.

8 P a g e 7 Quality of life implications: The key measure of benefit for the health economic appraisal of new technologies is the Quality Adjusted Life Year (QALY). The QALY is used in routine decision making by a number of health care decision making authorities throughout the world, including the National Institute for health and Clinical Excellence (NICE) in the UK. QALY gains of adopting a new intervention can be estimated as a combination of the reduction in mortality (additional life years) and health related quality of life of a patient during those life years. For example, if an amputee patient were to gain an extra 1 year of life as a result of a procedure, but only had 20 functioning across the measures of quality of that life year, then his / her QALY score would be 0.2 (1*.2). In the case of our analysis, the authors are not aware of any studies which explicitly measure QALY implications for diagnostic tools for acute compartment syndrome. However, it is likely that the implications would be substantial, especially the quality of life implications for preventing an amputation. One study has aimed to illustrate the health burden associated with traumatic amputations, measured using the SF-36 quality of life instrument 8. The study found that, in particular, physical functioning scores averaged 37.5 points less relative to the general population, representing a statistically significant difference. Role limitations, bodily pain and general health scores all showed statistically significantly worse outcomes for the amputee group. The study also showed a significantly lower proportion of amputees were employed in the workplace, further adding to the likely emotional and psychological implications. An additional study (the LEAP study) 9 found that, after running a simulation to incorporate the probabilities of complication, that utilities (health outcomes) were lower for amputee patients even compared to those undergoing limb salvage (0.954 vs ). This represented a QALY loss of per year for amputation compared with limb salvage. Due to a lack of published data fitting to our research question, we have refrained from making predictions of the magnitude of QALY implications. However, based on the predicted clinical benefit of early diagnosis, it is highly likely that this would translate into substantial gains in patient quality of life. Future research is required to investigate such QALY implications in this context and in order to accurately quantify the impact for the use in economic evaluation of such new and emerging technologies. The consideration of such QALY aspects would likely improve the cost-effectiveness case still further, generating improved quality of life at a cost saving to health care providers. The additional health benefits (QALYs) and cost savings could be expected to accumulate over a longer period (in the case of an amputation prevented a patients whole lifetime).

9 P a g e 8 Discussion: Our analysis, whilst comprehensive in resources included, is surrounded by considerable uncertainty in the magnitude of those resource requirements, especially as some of the scenarios are exploratory and further work is required to establish the exact level of resource use. As the diagnostic tool is not currently available right across the UK, the potential reductions in cases and the hypothesised stages of care are best guesses and estimates are not intended to be 100% accurate. They are however, an indication of the magnitude of cost associated with this clinical area and suggest, at the very least, that on economic grounds alone, this intervention warrants further investigation to establish its true accuracy, and ultimately an investigation of its cost-effectiveness with a view to implementation into routine care. Therefore, this costing exercise, while illustrative and important, should be interpreted with caution. Specifically, our analysis has been conservative and has not accounted for a number of potentially high value cost considerations, which may significantly increase the cost savings of using the technology, but which are difficult to estimate with precision. A number of key issues to be considered alongside the analysis are: 1. Life time costs of treating a patient to the health services: Our analysis is over a 12 month time horizon post hospital discharge and does not account for life-time follow up of limb salvage or amputation patients. The resource use associated with this is likely to be substantial, and the total impact to the NHS is of course dependant on the age of the patient. One study in the USA has estimated that, for a 20 year old male needing a below the knee amputation, life time (undiscounted) costs are estimated at $680,000 USD (approximately = 429,000) 9, taking account the time value of money and discounting at a rate of 3.5% per annum, the estimated cost (in today s money), would be about $325,000 USD (approximately = 205,000) per case. For a limb salvage patient (stage 4 in our analysis), the same study estimated the life-time costs for a 20 year old male at approximately $200,000, and a discounted lifetime cost of $125,000 (or 78,750) 9. Therefore, based on our predicted numbers and these cost estimates, the lifetime cost savings to the NHS are likely to be significantly higher than those reported, perhaps as much as 33.5m cost savings [( 205,000*130) + ( 78750*87)] for the prevention of stages 4 and 5 alone.

10 P a g e 9 2. Costs presented are only for 1 year. The costs presented in the analysis in table 2 are for annual incidences only. It could be expected that these incidences of fractures will recur year on year. Therefore, based on the lifetime costs of (1) above, over a 10 year period, the cost savings to the NHS for ACS in tibial fractures alone could be over 335 million. 3. A wider case for use of the probe: As this example of costing is applied to the case of tibial shaft fractures (which only represent about 35% of ACS cases presenting to the orthopaedic ward 1 ), our analysis does not account for cost savings which may be generated from other injuries and scenarios where this test would also be useful (e.g. Complex knee injuries, forearm shaft fractures and other injuries caused, for example, as a result of road traffic accidents). Such cases may require even greater numbers of amputations if ACS is missed, and may incur similar or greater cost and quality of life implications. For example, it is possible that the quality of life implications of an amputated forearm are as severe as or worse than a below the knee amputation. 4. Costs to society: There are considerable costs to society in terms of benefit payments, lost days from work, retraining and supporting amputee patients. The exact costs are dependent on the work in which the patient is involved. For example, the costs of time off work, retraining, developing new skills etc may be much higher for a manual labourer than an office worker; however they are likely to be substantial in magnitude. 5. Costs to patients and family: There may be substantial costs to patients, and their families in terms of adapting their life and adjusting to a poorly functioning limb or the loss of a limb. We have highlighted some of the potential QALY implications in the previous section. Emotional stress as well as physical limitations will have impact on not only patient quality of life, but also on their families, carers and the impact on their daily lives. The loss of a job, and the difficulties this creates would likely magnify both the financial and psychological burden to patients, families and their carers.

11 P a g e Litigation costs: In addition to avoiding the sequelae of missed diagnosis, there is also an urgency to reduce the number of malpractice claims. The impact of litigation costs from a missed diagnosis of compartment syndrome is substantial. One particular US study 10 has found that the average indemnity payment for compartment syndrome was approximately $426,000 (over 268,000). This was considerably higher than the average orthopaedic indemnity payment of $136,000. The study found that 75% of malpractice claims for orthopaedic surgeons are closed in favour of the surgeon, only 7/16 compartment syndrome cases resulted in the same conclusion. This study has thus shown compartment syndrome represents an area of increased liability in orthopaedic care 10. The exact magnitude of cost and QALY implications will need to be confirmed in a future definitive trial of the intervention, before clear recommendations can be made to health care professionals. Combining the health services costs explored in table 2 with those outlined in discussion points above, we can see that the potential overall cost savings to the health services are likely to be substantial over a 10 year period. Our work indicates that this new simple and inexpensive piece of kit has the potential to be highly cost-effective and may also have significant implications on long term quality of life gains from a correct and early diagnosis of acute compartment syndrome. Conclusion: The simplistic and pragmatic nature of this device suggests that if its effectiveness is proven, there is great potential for this diagnostic probe to be implemented in routine practice across the UK and further afield at significant cost savings to health care providers and decision makers such as NICE and SIGN. Sensitivity analysis indicates the variation in these cost savings based on the assumptions made, however, given the highlighted limitations, there is still great potential for the costeffectiveness of this intervention, with likely quality of life (QALY) gains accruing at substantial cost savings to the health services. These should be considered alongside the savings to the patient (e.g. time lost at work) and to society in general (in terms of benefit payments over a lifetime). While this work indicates great potential, further work is required to confirm our results, establish diagnostic accuracy compared to gold standard pressure measures, and hence a robust measure of costeffectiveness.

12 P a g e 11 References: 1. Clinical expert opinion, Professor Alan Johnstone, NHS Grampian and University of Aberdeen, Information services division. Scotland, Speciality costs, codes R040 R046; 2011 [accessed April 2012]. URL: 3. Curtis L. Unit Costs of Health and Social Care. Kent: Personal Social Services Research Unit, University of Kent; 2011 [accessed April 2012]. URL: 4. Court-Brown CM, McBirnie J.The Epidemiology of tibial fractures. J Bone Joint Surg 1995; 77- B: Office for National Statistics. Annual mid year population estimates 2010, June 2011 online [accessed May 2012]. URL: s% pdf 6. Reverte MM, Dimitriou R, Kanakaris N, Giannoudis PV. What is the effect of compartment syndrome and fasciotomies on fracture healing in tibial fractures? Injury, Int J. Care Injured 42 (2011) Wheeles C. Wheeles textbook of orthopaedics, Online [accessed May 2012]. URL: 8. Pezzin L, Dillingham TR, MacKenzie EJ. Rehabilitation and the long-term outcomes of persons with trauma-related amputations. Archives of physical medicine and rehabilitation 2000; 81 (3) Chung K, Sadawi-Konefka BS, Hasse S, Kaul G. A cost-utility analysis of amputation versus salvage for Gustilo IIIB and IIIC Open Tibial Fractures. Plast Reconstr Surg December; 124 (6): 1965:1973.

13 P a g e Bhattacharyya T, Vrahas M. The medical-legal aspects of compartment syndrome. 2004, The journal of bone and joine surgery 86-A (4) Appendix: Table A1: Detailed breakdown of scenario costs to the health services over the first year of treatment. Best case scenario 1 (earliest possible diagnosis no significant muscle damage). Resource use Unit cost ( ) Total Costs ( ) Source Initial fracture surgery theatre (hours*) , ISD R142X Hospital stay (nights**) ,308 ISD R040 Physio consultations (N) PSSRU 2011 Orthopaedic O/P (N) ISD R044 GP consultations (N) PSSRU 2011 Total costs 4, O/P = outpatients; Physio = physiotherapist; GP=General practitioner; ISD = Information services division; PSSRU = personal and social services research unit. * Surgery time in an orthopaedic theatre. ** Number of nights spent in hospital (on an orthopaedic ward) Table A2: Best case scenario 2 (appropriate diagnosis with moderate muscle damage). Proportion Resource Unit cost Total Source use ( ) Costs ( ) Initial surgery & fasciotomy , ISD R142X hours* 2 nd procedure skin graft (hours*) , ISD R142X Hospital stay (nights**) , ISD R040 Physio consultations (N) PSSRU 2011 Orthopaedic O/P (N) ISD R044 Gp consultations (N) PSSRU 2011 Future plastic surgery (hours***) ISD R142X Future plastic surgery (nights***) ISD R040 Total costs 11,558.56

14 P a g e 13 O/P = outpatients; Physio = physiotherapist; GP=General practitioner; ISD = Information services division; PSSRU = personal and social services research unit. * Surgery time in an orthopaedic theatre. ** Number of nights spent in hospital (on an orthopaedic ward) *** refers to the assumed length of surgery and number of nights spent as a hospital inpatient for an average case receiving this care / procedure, and is assumed similar to resource use in an orthopaedic care setting.

15 P a g e 14 Table A3: Current practice late but correct diagnosis Proportion Resource Unit cost Total Source use ( ) Costs ( ) Initial surgery & fasciotomy , ISD R142X (hours)* 2 nd procedure inspection , ISD R142X (hours*) 3 rd procedure skin graft , ISD R142X (hours*) Hospital stay (nights**) , ISD R040 Physio consultations (N) PSSRU 2011 Ortho O/P (N) ISD R044 GP consultations PSSRU 2011 Future plastic surgery (hours***) ISD R142X Future plastic surgery (nights***) ISD R040 Future ortho surgery (hours***) ISD R142X Future ortho surgery (nights***) ISD R040 Total costs 17, O/P = outpatients; Physio = physiotherapist; GP=General practitioner; ISD = Information services division; PSSRU = personal and social services research unit; ortho = orthopaedics. * Surgery time in an orthopaedic theatre. ** Number of nights spent in hospital (on an orthopaedic ward) *** refers to the assumed length of surgery and number of nights spent as a hospital inpatient for an average case receiving this care / procedure, and is assumed similar to resource use in an orthopaedic care setting.

16 P a g e 15 Table A4: Potential costs of missed acute compartment syndrome. (Limb salvage) Proportion: Resource Unit Total Costs Source use cost ( ) ( ) Initial surgery & fasciotomy , ISD R142X (hours)* 2 nd procedure inspection , ISD R142X (hours*) 2 nd procedure inspection , ISD R142X (hours*) 2 nd procedure inspection , ISD R142X (hours*) 5 th procedure skin graft (hours*) , ISD R142X ICU (nights**) , ISD R040 HDU (nights**) ISD R040 Hospital stay - ward (nights**) , ISD R040 Physio consultations (N) , PSSRU 2011 Ortho O/P (N) , ISD R044 Plastic O/P (N) , ISD R044 GP consultations (N) PSSRU 2011 Future plastic surgery (hours*) ISD 142X Future plastic surgery (nights**) ISD R040 Future Ortho surgery (hours***) , ISD 142X Future Ortho surgery (nights ***) ISD R040 Future surgery foot / ankle ISD R142X deformities (hours***) Future surgery foot/ankle ISD R040 deformities (nights***) Orthotic O/P (N)**** ISD R044 Ankle / Foot orthoses (component costs) 1 2 1,000 2, MARS, Woodend hospital Total costs 36, O/P = outpatients; Physio = physiotherapist; GP=General practitioner; ISD = Information services division; MARS = Mobility and rehabilitation services; PSSRU = personal and social services research unit; ortho = orthopaedics. * Surgery time in an orthopaedic theatre. ** Number of nights spent in hospital (on an orthopaedic ward) *** refers to the assumed length of surgery and number of nights spent as a hospital inpatient for an average case receiving this care / procedure, and is assumed similar to resource use in an orthopaedic care setting. **** Orthotic outpatient department assumed to incur the same costs as orthopaedic.

17 P a g e 16 Table A5: Potential costs of missed acute compartment syndrome (Limb amputation required) Proportion Resource Unit Total Costs Source use Cost ( ) ( ) Initial surgery & fasciotomy , ISD R142X (hours)* 2 nd procedure inspection , ISD R142X (hours*) 3 rd procedure inspection , ISD R142X (hours*) 4 th procedure inspection (hours*) , ISD R142X Amputation (hours*) , ISD R142X HDU (nights **) ISD R040 ICU (nights**) , ISD R040 Hospital stay (nights) , ISD R040 Physio consultations (N) , PSSRU 2011 Ortho O/P (N) , ISD R044 GP consultations (N) PSSRU 2011 Future surgery-stump problems (hours***) Future surgery-stump problems (nights***) Prosthetic O/P to fit prosthesis **** Component cost of prosthetics (above knee)^ Component cost of prosthetics (below knee)^ ISD R142X ISD R ISD R ,000 2, MARS, Woodend hospital ,500 4, MARS, Woodend hospital Socket cost for limb 1 2 1,000 2, MARS, Woodend hospital Rehabilitation for prosthetic limb (1 st appt) NHS ref costs Follow up appointments for prosthesis , NHS refcosts Powered wheelchair PSSRU Regular wheelchair PSSRU Total costs 40, O/P = outpatients; Physio = physiotherapist; GP=General practitioner; HDU = High Dependancy Unit; ICU = Intensive Care Unit; ISD = Information services division; MARS = Mobility and rehabilitation service; PSSRU = personal and social services research unit; ortho = orthopaedics. * Surgery time in an orthopaedic theatre. ** Number of nights spent in hospital (on an orthopaedic ward) *** refers to the assumed length of surgery and number of nights spent as a hospital inpatient for an average case receiving this care / procedure, and is assumed similar to resource use in an orthopaedic care setting. **** prosthetic outpatient department assumed to incur the same costs as orthopaedic for fitting of prosthesis procedure. ^ Component costs are calculated as follows: Each amputation requires the provision of 2 artificial legs, one for wearing and one spare.