COMMISSIONING POLICY

Transcription

1 COMMISSIONING POLICY Endovascular Repair of Abdominal Aortic Aneurysm (EVAR) for patients with a higher perioperative mortality risk Specialty Vascular Surgery Distribution list All Worcestershire GP Practices All providers Contact regarding this policy: Worcestershire PCT Acute Commissioning Team Page 1 of 11

2 CONTRIBUTION LIST Key individuals involved in developing the document Name Designation Mr A Atwal Consultant Vascular Surgeon, Worcestershire Acute Hospitals NHS Trust Dr Vijay Consultant Radiologist, Worcestershire Acute Hospitals NHS Trust Anita Roberts Commissioning & Service Redesign, Worcestershire Primary Care Trust Dr Alexis Macherianakis Consultant in Public Health, Worcestershire Primary Care Trust Mr A Garnham Consultant Vascular Surgeon, Wolverhampton Hospitals NHS Trust Dr Collins Consultant Radiologist, Wolverhampton Hospitals NHS Trust Circulated to the following individuals for consultation Name Designation Chris Emerson Head of Acute Commissioning, Worcestershire Primary Care Trust Mandy Matthews New Drugs & Technologies Advisor, Worcestershire Primary Care Trust Viv England General Manager Surgery, Worcestershire Acute Hospitals NHS Trust Ratified by: Worcestershire Professional Executive Committee (PEC) Contact regarding this policy: Worcestershire PCT Acute Commissioning Team Page 2 of 11

3 SUMMARY Endovascular Repair of Abdominal Aortic Aneurysm (EVAR) is routinely supported in Worcestershire for patients meeting one of the following criteria: - Patient is fit for open repair and has a hostile abdomen; or - Co-existing malignancy awaiting primary surgical intervention and with an expected survival >5 years; or - Patient is fit for open repair but has a predicted perioperative mortality risk as between 5 15% and who meet all the criteria described in 9.4. This policy only applies to standard stent grafts with an approximate cost of 5,500. Patients requiring fenestrated or branched endografts will be considered on an individual case basis through the PCT Process for Managing Individual Patient Referrals. Patients not meeting either of the above eligibility criteria for EVAR will be considered on an individual case basis through the PCT Process for Managing Individual Patient Referrals. This policy applies to elective EVAR procedures only. As there remains insufficient evidence of clinical benefit and long term outcomes of EVAR in high risk patients unfit for open repair (EVAR 2), Worcestershire PCT does not support EVAR in this group of patients. 1. Introduction 1.1 This Commissioning Policy outlines the management of patients who are suitable for open elective repair of an infrarenal abdominal aortic aneurysm (AAA), but who have a high peri-operative (30 day period after their operation) mortality risk of 5% or more if such surgery is undertaken. The policy has been jointly agreed between PCT commissioners and the vascular surgeons at Worcestershire Acute Hospitals NHS Trust. The policy is based on the rationale described by Cronenwett, following publication of the results of two large randomised trials to compare the outcome of endovascular and open surgical techniques for repair of AAA. It seeks to target health care resources at those who, although fit for open repair, are at higher risk of dying within a 30 day period after their operation. Whilst recognising the evidence of benefit from endovascular repair to those at lower risk, in the presence of a relatively high operative mortality rates, both nationally and locally, for elective AAA open repair (currently 2.5% in Worcester), it is appropriate that in the first instance, priority is given to those facing higher risks. It is recognized that revision of this rate may be necessary depending upon the results of regular and frequent audit of mortality from AAA and expenditure on endovascular repair. 1.2 To ensure both clinical appropriateness and effective use of NHS resources, the application of this policy will be reviewed quarterly for 12 months following implementation. If it is felt that the policy is seriously flawed, it will be suspended and the position reviewed. 2. What is an Abdominal Aortic Aneurysm (AAA)? 2.1 An aneurysm is defined as an abnormal dilatation of the artery that is 1.5 times the diameter of the normal segment. A diameter of greater than 3 cm in the abdominal aorta is generally regarded as aneurysmal. Contact regarding this policy: Worcestershire PCT Acute Commissioning Team Page 3 of 11

4 3. What causes AAA? 3.1 AAA is a condition commonly associated with old age. Most aneurysms are caused by degenerative disease affecting the vessel, the exact cause of which is largely unknown although risk factors for atherosclerotic disease such as smoking, hypertension, hyperlipidaemia and diabetes mellitus contribute significantly to the risk. AAA is also familial with a 4 10 fold increase in risk for those with a positive family history. Genetic influences also increase the risk with a 10-fold increase if a first degree relative is affected, rising to 20-fold if a sibling is affected. 4. The epidemiology of AAA 4.1 Approximately 75% of AAA are asymptomatic and are found incidentally during clinical examination or radiographic investigations. Therefore the exact prevalence is unknown but various screening studies have estimated between 1.7% and 6% in the older male population 1. The Vascular Society reports a prevalence of around 7.5% in men over 65, and relatively rare in men under the age of 55 years. AAA is also more common in men and accounts for nearly 2% of all deaths in men over Current management and alternative procedures 5.1 The standard method of treatment is by a major operation ( open repair ), in which the aneurysm is opened and an artificial graft sewn in place to replace the weakened section of blood vessel. This is a major procedure and surgery has a risk particularly in older, frail patients. 5.2 Intervention for AAA is designed to prevent the endpoint of rupture, which has an overall mortality rate of approximately 80%. However, all interventions for AAA are highly invasive and carry an associated risk of morbidity and mortality. The UK Small Aneurysm Trial demonstrated that there was no long-term survival advantage from elective surgery on small aneurysms (<5.5 cm diameter). Therefore, interventional treatment is not considered unless the AAA is more than 5.5 cm in diameter or more than 4.5 cm with an increase in size by more than 0.5 cm in the preceding 6 months. 5.3 In AAA s more than 5.5cm (or 4.5cm with an increase in size of more than 0.5cm in the preceding 6 months), open surgery is normally considered and has a mortality rate between 2% and 6%. 6. Endovascular Aneurysm Repair (EVAR) 6.1 Endovascular aneurysm repair involves positioning of an endograft within the abdominal aorta by a transfemoral or transiliac route with the aim of exclusion of the aneurysm from the circulation. Access to the femoral arteries is achieved by an incision in the groin and the graft is inserted via a preloaded delivery catheter system. Radio-opaque markers on the catheter and stent graft allow the endoprosthesis to be manoeuvred into position under fluoroscopic guidance. Following successful insertion of the stent-graft, an angiogram is performed to confirm successful placement. 1 A systematic review update of the recent evidence for the safety and efficacy of elective endovascular repair in the management of infrarenal abdominal aortic aneurysms, NICE, June 2005 Contact regarding this policy: Worcestershire PCT Acute Commissioning Team Page 4 of 11

5 7. National guidance 7.1 The National Institute for Health and Clinical Excellence (NICE) has issued Interventional Procedure Guidance (IPG163) which concludes that: Current evidence on the efficacy and short-term safety of stent graft placement in abdominal aortic aneurysm appears adequate to support the use of this procedure provided that the normal arrangements are in place for consent, audit and clinical governance The full guidance is available on the NICE website at the following address: 8. EVAR in Worcestershire 8.1 In considering the above advice and acknowledging EVAR is a technique that is still developing, but which may in the future be routinely offered, Worcestershire PCT does not support EVAR in low risk patients. This decision was based on the current evidence available, which suggests there is no clear benefit of EVAR over open repair in low-risk patients In light of the uncertainty in relation to the clinical and cost effectiveness of EVAR over open repair alongside the higher costs of the procedure, Worcestershire PCT has not been routinely supporting EVAR in the treatment of AAA. The only circumstances in which EVAR is being supported is in patient s who are considered to be low risk but who cannot undergo open repair due to physical and/or anatomical reasons - for example patients with a hostile abdomen, which may be defined as multiple previous (more than 2) laparotomies, enterostostomy, previous extensive radiotherapy and other causes of extensive internal scarring or adhesions that would make conventional open repair technically difficult. Prior authorisation has to be sought from the PCT for such requests and will be considered through the PCT Individual Patient Request and Complex Case Procedure. 9. Extending the provision of EVAR in Worcestershire 9.1 Following discussions with the Vascular Team at Worcestershire Acute Hospitals NHS Trust, it became apparent there was a group of patients deemed unsuitable for open repair due to a high perioperative mortality risk in which EVAR would reduce the mortality risk to being comparable with the risks associated with open repair. 9.2 However, EVAR should not be offered routinely to all patients with AAA. Only patients deemed fit for open repair who are assessed as having a higher perioperative mortality risk are covered in this policy. There are no robust clinical data on which to base a recommended operative mortality rate at which endovascular repair should be offered as a routine option. Many trials report the average 30-day mortality following open repair as 5%, with population operative mortality rates higher in the range 7-10%. This difference can be attributed to the unselected nature of populations compared to those of study groups. Therefore, given the local perioperative mortality rate for open repair quoted as 2 EVAR trial participants. Comparison of endovascular aneurysm repair with open repair of abdominal aortic aneurysm (EVAR trial 1): randomised controlled trial. Lancet 2004;364: EVAR trial participants. Endovascular aneurysm repair and outcome in patients unfit for open repair of abdominal aortic aneurysm (EVAR trial 2): randomised controlled trial. Lancet 2005;365: Contact regarding this policy: Worcestershire PCT Acute Commissioning Team Page 5 of 11

6 2.5%, any patient with a predicted perioperative mortality rate of >5% is defined as having a higher operative mortality risk. Clearly, this represents no more than a best estimate of the lower level of predicted mortality for targeting endovascular repair. It is recognized that revision of this rate may be necessary depending upon the results of regular and frequent audit of mortality from AAA and expenditure on endovascular repair. The assessment of operative risk is largely empirical. In Worcestershire, the perioperative mortality risk should be determined following a joint assessment by the vascular surgeon and anaesthetist aided by supplementary diagnostic tests such as echocardiography and cardio-pulmonary exercise testing. For the purposes of audit, prospective data will be collected, and V- Possum used as an audit tool to confirm appropriate risk assessment of patients chosen for EVAR. 9.3 The following criteria describe general characteristics of patients to whom elective endovascular repair may be offered as a routine treatment option and have been locally agreed between the PCT Public Health and Vascular Surgeons at Worcestershire Acute Hospitals NHS Trust. They are NOT: Mandatory. Clinicians and their patients may decide that open repair is a preferable option Applicable to patients in whom a fenestrated or branched stent graft is being considered Applicable to emergency procedures 9.4 The criteria is as follows: o In view of the present uncertainty on the long term durability of stents-grafts, patients should have a life expectancy at the time of the operation of less than 10 years. In general this will mean that they will be older than 65 years; o Patients must be assessed as being fit for open repair 3 by the referring team, which includes a vascular surgeon and anaesthetist, i.e. if endovascular repair was not available, would the patient be offered open surgery as treatment?; o EVAR should be considered as a treatment option in all patients over the age of 80 who have been assessed as having a predicted operative mortality of between 5-15%; o Aneurysm diameter (Dmax) must be greater than 5.5cms. o Neck length should be more than1.5cms and neck diameter less than 3.2cms o At least one iliac system (external and common iliac artery) must be patent with a minimum diameter (Dmin) equal to or greater than 7mms. o Other factors that impact upon feasibility of endovascular repair such as tortuosity and calcification will also be assessed. If in doubt about quality of access vessels, patients should be referred to a tertiary centre for advice. 9.5 The V-POSSUM Score will be used to assess an individual patients level of risk for EVAR. A copy of the data set to be used is available in Appendix 1. 3 Patient fitness for open repair will be decided at a local level, although the following guidelines should be used to provide some assistance in determining fitness: Cardiac status: Normally patients presenting with the following cardiac symptoms would not be recommended for any surgical intervention: o MI within last 3 months; o Onset of angina within the last 3 months; o Unstable angina at night or at rest Respiratory status: Surgical intervention would not be recommended for patients presenting with the following respiratory symptoms: o Unable to walk up a flight of stairs without shortness of breath; o FEV1 < 1.0L o PO2 < 8.0 Kpa o PCO2 > 6.5 Kpa Contact regarding this policy: Worcestershire PCT Acute Commissioning Team Page 6 of 11

7 9.6 In addition to the patients described above, endovascular repair can be clinically indicated in a number of other situations in patients <65 years or with a life expectancy of more than a decade and those with predicted operative mortality of <5%. It is anticipated that the majority of these patients will fall into one of the categories described below: a) Hostile abdomen this will be defined locally but will usually include those patients who have had multiple (>2) previous laparotomies, enterostostomy, previous extensive radiotherapy, or other causes of extensive internal scarring or adhesions that would make conventional open repair technically difficult,. b) Co-existing malignancy awaiting primary surgical intervention and with an expected survival >5 years 9.7 Patients at very high operative risk may be considered for endovascular repair at a later date subject to a favourable response to medical therapy that reduces their risk (e.g. no MI for >6 months). 9.8 The use of fenestrated or branched endografts in patients who do not satisfy the criteria described in this protocol is at the discretion of individual PCTs and is outside this policy. These will be the subject of an exceptional case request. Important Note: Patients classified as EVAR 2 ie. unfit for open repair, should not be offered endovascular repair and shold be managed within conventional NHS services normally available. 10. Likely numbers for EVAR 10.1 Approximately elective open repairs are performed by Worcestershire Acute Hospitals NHS Trust per annum. Open repairs are performed within Worcestershire by the Vascular Team Approximately 5 EVAR procedures are undertaken annually in patients with a hostile abdomen. These patients are referred to the Royal Wolverhampton Hospital NHS Trust as one of the regional EVAR centre for the West Midlands It is anticipated that approximately patients per annum will meet the above criteria for EVAR. About of these would have previously been treated with open repair, despite their higher risk of operative mortality. 11. Comparative treatment costs 11.1 The EVAR trials quoted comparative treatment costs of: Open-repair 5,803 Endovascular Stent 5,803 + hardware costs of c. 5, Average length of stay in EVAR patients is 3 days in comparison to patients undergoing open repair who have an average length of stay of 7 8 days. Since the EVAR trials, clinical practice has evolved leading to hospital stays being reduced, reintervention rates, although high initially, are also being reduced and follow up protocols have been simplified, reducing the overall cost. Contact regarding this policy: Worcestershire PCT Acute Commissioning Team Page 7 of 11

8 12. Commissioning Policy Statement for EVAR in Worcestershire: 12.1 EVAR is routinely supported in Worcestershire for patients meeting one of the following criteria: Patient is fit for open repair and has a hostile abdomen; or Co-existing malignancy awaiting primary surgical intervention and with an expected survival >5 years; or Patient is fit for open repair but has a predicted perioperative mortality risk as between 5 15% and who meet all the criteria described in This policy only applies to standard stent grafts with an approximate cost of 5,500. Patients requiring fenestrated or branched endografts will be considered on an individual case basis through the PCT Process for Managing Individual Patient Referrals Patients not meeting either of the above eligibility criteria for EVAR will be considered on an individual case basis through the PCT Process for Managing Individual Patient Referrals This policy applies to elective EVAR procedures only As there remains insufficient evidence of clinical benefit and long term outcomes of EVAR in high risk patients unfit for open repair (EVAR 2), Worcestershire PCT does not support EVAR in this group of patients. 13. Referral Pathways for EVAR in Worcestershire 13.1 There is a Vascular Surgeon and Radiologist forming the EVAR teams at both Wolverhampton and Worcestershire. These two teams have been working as an informal network in order to manage patients requiring EVAR since May Patients in Worcestershire being considered for EVAR will be initially identified and investigated by the Vascular Surgeon in Worcestershire. The CT scans will be discussed and measured for EVAR by the Vascular Surgeon and Radiologist jointly.. The information will then be shared with the team in Wolverhampton via electronic link to determine the appropriateness of undertaking EVAR. This will be followed with a discussion between the two teams usually by or telephone. If considered necessary, the teams will meet in either Worcester or Wolverhampton to discuss the management of more clinically complicated individual cases In the majority of cases, the standard infrarenal EVARs will be undertaken in Worcester. If unusual technical difficulty is anticipated, the Vascular Surgeon from Wolverhampton may be asked to attend the case in Worcester or the patient will be transferred to Wolverhampton for surgery. This decision will reflect the view of the two teams as to how an individual patient should be managed, with the Vascular Surgeon from Wolverhampton acting as clinical lead Patients requiring fenestrated or branch grafts will be transferred to Wolverhampton for surgery. Contact regarding this policy: Worcestershire PCT Acute Commissioning Team Page 8 of 11

9 13.5 Post-operative follow up of standard EVAR patients will be in Worcestershire. It is anticipated that follow up of complex fenestrated or branch graft patients will be in Wolverhampton for the initial post-operative period, after which the patients follow up care will be transferred to Worcester, following agreement by both teams that this is clinically appropriate Any post-operative EVAR patients requiring emergency admission for complications will initially be admitted to Worcestershire Royal Hospital and assessed by the on call Vascular Surgeon. If a complication is specific to the patient s EVAR, advice will be sought from the Worcester EVAR team. In the absence or unavailability of either or both members of this team, the case will be discussed with the Wolverhampton team and the patient transferred to Wolverhampton for further management if deemed clinically necessary. 14. Audit and review 14.1 Data on all patients undergoing EVAR in Worcestershire is being submitted to the national Registry For Endovascular Treatment Of Aneurysms (RETA) on a prospective basis. A copy of the dataset to be collected is available in Appendix All patients undergoing EVAR will entered on to the National Vascular Database (NVD), an initiative of the Vascular Society of Great Britain and Ireland. The comprehensive dataset collected for this includes the following sub-headings: Demographic data Admission Medical History Indications for surgery Pre-operative tests Pre-operative laboratory investigations Procedure Complications Destination and Discharge 14.3 This data will be collected prospectively and will form the basis of audit of EVAR in Worcestershire. This will be reported on 6 monthly intervals to the Clinical Audit Group This commissioning policy statement will be reviewed on an annual basis and reassessed in light of the audit results. In the event of there being evidence of clinical issues ie. patient selection, outcomes etc, the policy and the commissioning of this service will be reviewed. Contact regarding this policy: Worcestershire PCT Acute Commissioning Team Page 9 of 11

10 Appendix 1 V-POSSUM DATA-SET Physiological Parameters Age < 61 yrs old Cardiac No cardiac failure Respiratory No dyspnoea ECG ECG normal Systolic BP mmhg Pulse Rate bpm Haemoglobin g/dl WBC 4-10 Urea <7.6 Sodium >135 mmol/l Potassium mmol/l GCS 15 Operative Parameters Operation Type Minor Operation Number of procedures one Operative Blood Loss <100 mls Peritoneal Contamination No soiling Malignancy Status not malignant CEPOD Contact regarding this policy: Worcestershire PCT Acute Commissioning Team Page 10 of 11

11 Contact regarding this policy: Worcestershire PCT Acute Commissioning Team Page 11 of 11