Systematic review and meta-analysis comparing the autogenous vein bypass versus a prosthetic graft for above-the-knee femoropopliteal bypass surgery in patients with intermittent claudication

OBJECTIVES

According to guidelines, the autogenous saphenous vein (ASV) is the preferred conduit for femoropopliteal bypass surgery in all patients with peripheral artery disease. However, in contrast to patients with critical limb ischemia (CLI), patients with intermittent claudication (IC) only, tend to have milder disease, and thus a prosthetic graft may be as good as a vein conduit. The objective of this study was to compare patency rates of the ASV and a prosthetic graft in femoropopliteal bypass surgery in patients with IC.

METHODS

A systematic literature search was performed in the PubMed, Embase, and Cochrane databases to identify randomized controlled trials comparing prosthetic graft versus ASV in patients with IC. Articles with a mixed IC and CLI study population were included if more than 50% of the study cohort was treated for IC. Primary analysis was performed on IC patients only. Secondary analysis was performed on the mixed group. The primary endpoint was short- and long-term patency and secondary endpoints were complications, limb salvage, and mortality.

RESULTS

In total, six studies with 524 patients were included. Only two studies reported solely on patients with IC. All these patients underwent above-the-knee bypasses and average patency rates at one and 5 years were 88% and 76% vs 81% and 68% in the ASV and the PTFE groups, respectively. One and five-year patency was not statistically different between the groups (OR 5.21; 95% CI 0.60-45.36 and OR 2.10; 95% CI 0.88-5.01). In a mixed population of patients with IC and CLI (84% IC patients), 1 year patency was comparable (OR 1.40; 95% CI 0.87-2.25). However, after a follow-up of over 3 years, this mixed group had significantly higher patency rates in favour of the ASV (OR 2.06; 95 % CI 1.30-3.26). Complication and amputation rates were comparable in both groups.

CONCLUSIONS

Limited data are available for patients receiving above-the-knee femoropopliteal bypass for intermittent claudication. The ASV remains the conduit of choice for femoropopliteal bypass surgery. However, the prosthetic conduit seems a feasible alternative for patients with intermittent claudication in whom the ASV is not present or unsuitable.

Patient-Reported Outcomes of Yearly Imaging Surveillance in Patients Following Endovascular Aortic Aneurysm Repair

Little is known about the impact of standardized imaging surveillance on anxiety levels and well-being of patients after endovascular aortic aneurysm repair (EVAR). We hypothesize that patient anxiety levels increase just before receiving the imaging results compared with standard anxiety levels.

METHODS

Prospective cohort study from November 2018 to May 2020 including post-EVAR patients visiting the outpatient clinics of 4 Dutch hospitals for imaging follow-up. The Patient-Reported Outcomes Measurement Information System (PROMIS) was used. Patients completed the PROMIS Anxiety v1.0 Short Form (SF) 4a, PROMIS-Global Health Scale v1.2, and PROMIS-Physical Function v1.2 SF8b at 2 time points: prior to the result of the imaging study (T1: pre-visit) and 6-8 months later (T2: reference measurement). Mean T-scores at T1 were compared to T2, and T2 to the general 65+ Dutch population.

RESULTS

Altogether 342 invited patients were eligible, 214 completed the first questionnaire, 189 returned 2 completed questionnaires and 128 patients did not participate. Out of 214 respondents, 195 were male (91.1%) and the mean (standard deviation) age was 75.2 (7.0) years. There were no significant differences between T1 and T2 in anxiety levels (0.48; 95% confidence interval[CI] -0.42-1.38), global mental health (0.27; 95% CI -0.79-0.84), global physical health (0.10; 95% CI -0.38-1.18) and physical function (0.53; 95% CI -0.26-1.32). Compared with the 65+ Dutch population, at T2 patients experienced more anxiety (3.8; 95% CI 2.96-5.54), had worse global physical health (-3.2; 95% CI -4.38 - -2.02) and physical function (-2.4; 95% CI -4.00 - -0.80). Global mental health was similar (-1.0; 95% CI -2.21 - 0.21).

CONCLUSIONS

Post-EVAR patients do not experience more anxiety just before receiving surveillance imaging results than outside this period, but do suffer from more anxiety and worse physical outcomes than the 65+ Dutch population.

Short-term outcomes of open surgical abdominal aortic aneurysm repair from the Dutch Surgical Aneurysm Audit

Background

The sharp decrease in open surgical repair (OSR) for abdominal aortic aneurysm (AAA) has raised concerns about contemporary postoperative outcomes. The study was designed to analyse the impact of complications on clinical outcomes within 30 days following OSR.

Methods

Patients who underwent OSR for intact AAA registered prospectively between 2016 and 2019 in the Dutch Surgical Aneurysm Audit were included. Complications and outcomes (death, secondary interventions, prolonged hospitalization) were evaluated. The adjusted relative risk (aRr) and 95 per cent confidence intervals were computed using Poisson regression. Subsequently, the population-attributable fraction (PAF) was calculated. The PAF reflects the expected percentage reduction of an outcome if a complication were to be completely prevented.

Results

A total of 1657 patients were analysed. Bowel ischaemia and renal complications had the largest impact on death (aRr 12·44 (95 per cent c.i. 7·95 to 19·84) at PAF 20 (95 per cent c.i. 8·4 to 31·5) per cent and aRr 5·07 (95 per cent c.i. 3·18 to 8.07) at PAF 14 (95 per cent c.i. 0·7 to 27·0) per cent, respectively). Arterial occlusion had the greatest impact on secondary interventions (aRr 11·28 (95 per cent c.i. 8·90 to 14·30) at PAF 21 (95 per cent c.i. 14·7 to 28·1) per cent), and pneumonia (aRr 2·52 (95 per cent c.i. 2·04 to 3·10) at PAF 13 (95 per cent c.i. 8·3 to 17·8) per cent) on prolonged hospitalization. Small effects were observed on outcomes for other complications.

Conclusion

The greatest clinical impact following OSR can be made by focusing on measures to reduce the occurrence of bowel ischaemia, arterial occlusion and pneumonia.

Effects of hospital preference for endovascular repair on postoperative mortality after elective abdominal aortic aneurysm repair: analysis of the Dutch Surgical Aneurysm Audit

BACKGROUND

Increased use of endovascular aneurysm repair (EVAR) and reduced open surgical repair (OSR), has decreased postoperative mortality after elective repair of abdominal aortic aneurysms (AAAs). The choice between EVAR or OSR depends on aneurysm anatomy, and the experience and preference of the vascular surgeon, and therefore differs between hospitals. The aim of this study was to investigate the current mortality risk difference (RD) between EVAR and OSR, and the effect of hospital preference for EVAR on overall mortality.

METHODS

Primary elective infrarenal or juxtarenal aneurysm repairs registered in the Dutch Surgical Aneurysm Audit (2013-2017) were analysed. First, mortality in hospitals with a higher preference for EVAR (high-EVAR group) was compared with that in hospitals with a lower EVAR preference (low-EVAR group), divided by the median percentage of EVAR. Second, the mortality RD between EVAR and OSR was determined by unadjusted and adjusted linear regression and propensity-score (PS) analysis and then by instrumental-variable (IV) analysis, adjusting for unobserved confounders; percentage EVAR by hospital was used as the IV.

RESULTS

A total of 11 997 patients were included. The median hospital rate of EVAR was 76.6 per cent. The overall mortality RD between high- and low-EVAR hospitals was 0.1 (95 per cent -0.5 to 0.4) per cent. The OSR mortality rate was significantly higher among high-EVAR hospitals than low-EVAR hospitals: 7.3 versus 4.0 per cent (RD 3.3 (1.4 to 5.3) per cent). The EVAR mortality rate was also higher in high-EVAR hospitals: 0.9 versus 0.7 per cent (RD 0.2 (-0.0 to 0.6) per cent). The RD following unadjusted, adjusted, and PS analysis was 4.2 (3.7 to 4.8), 4.4 (3.8 to 5.0), and 4.7 (4.1 to 5.3) per cent in favour of EVAR over OSR. However, the RD after IV analysis was not significant: 1.3 (-0.9 to 3.6) per cent.

CONCLUSION

Even though EVAR has a lower mortality rate than OSR, the overall effect is offset by the high mortality rate after OSR in hospitals with a strong focus on EVAR.

Editor's Choice - Nationwide Analysis of Patients Undergoing Iliac Artery Aneurysm Repair in the Netherlands

OBJECTIVE

The new 2019 guideline of the European Society for Vascular Surgery (ESVS) recommends consideration for elective iliac artery aneurysm (eIAA) repair when the iliac diameter exceeds 3.5 cm, as opposed to 3.0 cm previously. The current study assessed diameters at time of eIAA repair and ruptured IAA (rIAA) repair and compared clinical outcomes after open surgical repair (OSR) and endovascular aneurysm repair (EVAR).

METHODS

This retrospective observational study used the nationwide Dutch Surgical Aneurysm Audit (DSAA) registry that includes all patients who undergo aorto-iliac aneurysm repair in the Netherlands. All patients who underwent primary IAA repair between 1 January 2014 and 1 January 2018 were included. Diameters at time of eIAA and rIAA repair were compared in a descriptive fashion. The anatomical location of the IAA was not registered in the registry. Patient characteristics and outcomes of OSR and EVAR were compared with appropriate statistical tests.

RESULTS

The DSAA registry comprised 974 patients who underwent IAA repair. A total of 851 patients were included after exclusion of patients undergoing revision surgery and patients with missing essential variables. eIAA repair was carried out in 713 patients, rIAA repair in 102, and symptomatic IAA repair in 36. OSR was performed in 205, EVAR in 618, and hybrid repairs and conversions in 28. The median maximum IAA diameter at the time of eIAA and rIAA repair was 43 (IQR 38-50) mm and 68 (IQR 58-85) mm, respectively. Mortality was 1.3% (95% CI 0.7-2.4) after eIAA repair and 25.5% (95% CI 18.0-34.7) after rIAA repair. Mortality was not significantly different between the OSR and EVAR subgroups. Elective OSR was associated with significantly more complications than EVAR (intra-operative: 9.8% vs. 3.6%, post-operative: 34.0% vs. 13.8%, respectively).

CONCLUSION

In the Netherlands, most eIAA repairs are performed at diameters larger than recommended by the ESVS guideline. These findings appear to support the recent increase in the threshold diameter for eIAA repair.

Endovascular therapy versus femoropopliteal bypass surgery for medium-length TASC II B and C lesions of the superficial femoral artery: An observational propensity-matched analysis

Objectives

This study was designed to compare clinical outcomes of percutaneous transluminal angioplasty with optional stenting (PTA/s) and femoropopliteal bypass (FPB) surgery as primary invasive treatment in patients with medium-length superficial femoral artery (SFA) lesions.

Methods

We performed a single-center retrospective, observational analysis in all consecutive patients who had undergone initial invasive treatment for medium-length, TASC II B and TASC II C, SFA lesions from 2004 to 2015. Primary endpoints were primary and secondary clinical patency. Secondary endpoints were complication rates and number of amputations. Kaplan–Meier curves were used to compare patency rates in the two treatment groups. Multivariate Cox regression analysis was performed to adjust for confounding variables and propensity score matching analysis was used to balance treatment groups.

Results

A total of 362 patients with a mean observation period of 4.0 years (SD ± 2.6) were analyzed. In this group, 231 patients (64%) underwent PTA/s and 131 patients (36%) FPB surgery. There was no difference in primary clinical patency at one-, three- and five-year follow-up between the PTA/s and FPB group, with rates of 79% vs. 63%, 53% vs. 78% and 71% vs. 66%, respectively ( P = 0.46). Secondary clinical patency estimates were comparable, resulting in one-, three- and five-year secondary clinical patency rates of 88%, 76% and 67% in the PTA/s group versus 88%, 80% and 79% in the bypass group ( P = 0.40). Multivariate analysis revealed no significant differences between the PTA/s and FPB groups in terms of primary clinical patency (HR 1.4; 95% CI 0.9–2.2) and secondary clinical patency (HR 1.7; 95% CI 0.9–2.9). This was confirmed in the propensity score analysis. Hospital stay (4.8 vs. 10.3 days) and complication rate (2.6% vs. 18.3%) were significantly lower in the PTA/s group ( P = 0.00). The number of amputations was comparable ( P = 0.75).

Conclusions

The clinical success of endovascular therapy and surgery for medium-length SFA lesions is comparable. Taking into account the lower morbidity rate, shorter length of hospital stay and the less invasive character of PTA/s compared with bypass surgery, patients with medium-length SFA lesions are ideally treated by an endovascular-first approach.

Systematic review of mortality risk prediction models in the era of endovascular abdominal aortic aneurysm surgery

BACKGROUND

The introduction of endovascular aneurysm repair (EVAR) has reduced perioperative mortality after abdominal aortic aneurysm (AAA) surgery. The objective of this systematic review was to assess existing mortality risk prediction models, and identify which are most useful for patients undergoing AAA repair by either EVAR or open surgical repair.

METHODS

A systematic search of the literature was conducted for perioperative mortality risk prediction models for patients with AAA published since 2006. PRISMA guidelines were used; quality was appraised, and data were extracted and interpreted following the CHARMS guidelines.

RESULTS

Some 3903 studies were identified, of which 27 were selected. A total of 13 risk prediction models have been developed and directly validated. Most models were based on a UK or US population. The best performing models regarding both applicability and discrimination were the perioperative British Aneurysm Repair score (C-statistic 0·83) and the preoperative Vascular Biochemistry and Haematology Outcome Model (C-statistic 0·85), but both lacked substantial external validation.

CONCLUSION

Mortality risk prediction in AAA surgery has been modelled extensively, but many of these models are weak methodologically and have highly variable performance across different populations. New models are unlikely to be helpful; instead case-mix correction should be modelled and adapted to the population of interest using the relevant mortality predictors.

Adjusted Hospital Outcomes of Abdominal Aortic Aneurysm Surgery Reported in the Dutch Surgical Aneurysm Audit

OBJECTIVE/BACKGROUND

The Dutch Surgical Aneurysm Audit (DSAA) is mandatory for all patients with primary abdominal aortic aneurysms (AAAs) in the Netherlands. The aims are to present the observed outcomes of AAA surgery against the predicted outcomes by means of V-POSSUM (Vascular-Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity). Adjusted mortality was calculated by the original and re-estimated V(physiology)-POSSUM for hospital comparisons.

METHODS

All patients operated on from January 2013 to December 2014 were included for analysis. Calibration and discrimination of V-POSSUM and V(p)-POSSUM was analysed. Mortality was benchmarked by means of the original V(p)-POSSUM formula and risk-adjusted by the re-estimated V(p)-POSSUM on the DSAA.

RESULTS

In total, 5898 patients were included for analysis: 4579 with elective AAA (EAAA) and 1319 with acute abdominal aortic aneurysm (AAAA), acute symptomatic (SAAA; n = 371) or ruptured (RAAA; n = 948). The percentage of endovascular aneurysm repair (EVAR) varied between hospitals but showed no relation to hospital volume (EAAA: p = .12; AAAA: p = .07). EAAA, SAAA, and RAAA mortality was, respectively, 1.9%, 7.5%, and 28.7%. Elective mortality was 0.9% after EVAR and 5.0% after open surgical repair versus 15.6% and 27.4%, respectively, after AAAA. V-POSSUM overestimated mortality in most EAAA risk groups (p < .01). The discriminative ability of V-POSSUM in EAAA was moderate (C-statistic: .719) and poor for V(p)-POSSUM (C-statistic: .665). V-POSSUM in AAAA repair overestimated in high risk groups, and underestimated in low risk groups (p < .01). The discriminative ability in AAAA of V-POSSUM was moderate (.713) and of V(p)-POSSUM poor (.688). Risk adjustment by the re-estimated V(p)-POSSUM did not have any effect on hospital variation in EAAA but did in AAAA.

CONCLUSION

Mortality in the DSAA was in line with the literature but is not discriminative for hospital comparisons in EAAA. Adjusting for V(p)-POSSUM, revealed no association between hospital volume and treatment or outcome. Risk adjustment for case mix by V(p)-POSSUM in patients with AAAA has been shown to be important.

Venous Arterialisation for Salvage of Critically Ischaemic Limbs: A Systematic Review and Meta-Analysis

BACKGROUND

Critical limb ischaemia (CLI) is the end stage of peripheral artery disease (PAD) and is associated with high amputation and mortality rates and poor quality of life. For CLI patients with no revascularisation options, venous arterialisation could be a last resort for limb salvage.

OBJECTIVE

To review the literature on the clinical effectiveness of venous arterialisation for lower limb salvage in CLI patients with no revascularisation options.

METHOD

Different databases were searched for papers published between January 1966 and January 2016. The criteria for eligible articles were studies describing outcomes of venous arterialisation, published in English, human studies, and with the full text available. Additionally, studies were excluded if they did not report limb salvage, wound healing or amputation as outcome measures. The primary outcome measure was post-operative limb salvage at 12 months. Secondary outcome measures were 30 day or in-hospital mortality, survival, patency, technical success, and wound healing.

RESULTS

Fifteen articles met the inclusion criteria. The included studies described 768 patients. According to the MINORS score, methodological quality was moderate to poor. The estimated pooled limb salvage rate at one year was 75% (0.75, 95% CI 0.70-0.81). Thirty day or in-hospital mortality was reported in 12 studies and ranged from 0 to 10%. Overall survival was reported in 10 studies and ranged from 54% to 100% with a mean follow-up ranging from 5 to 60 months. Six studies reported on patency of the venous arterialisations performed, with a range of 59-71% at 12 months.

CONCLUSION

In this systematic review on venous arterialisation in patients with non-reconstructable critical limb ischaemia, the pooled proportion of limb salvage at 12 months was 75%. Venous arterialisation could be a valuable treatment option in patients facing amputation of the affected limb; however, the current evidence is of low quality.

Development and External Validation of a Model Predicting Death After Surgery in Patients With a Ruptured Abdominal Aortic Aneurysm: The Dutch Aneurysm Score

OBJECTIVE

The decision whether or not to proceed with surgical intervention of a patient with a ruptured abdominal aortic aneurysm (rAAA) is very difficult in daily practice. The primary objective of the present study was to develop and to externally validate a new prediction model: the Dutch Aneurysm Score (DAS).

METHODS

With a prospective cohort of 10 hospitals (n = 508) the DAS was developed using a multivariate logistic regression model. Two retrospective cohorts with rAAA patients from two hospitals (n = 373) were used for external validation. The primary outcome was the combined 30 day and in-hospital death rate. Discrimination (AUC), calibration plots, and the ability to identify high risk patients were compared with the more commonly used Glasgow Aneurysm Score (GAS).

RESULTS

After multivariate logistic regression, four pre-operative variables were identified: age, lowest in hospital systolic blood pressure, cardiopulmonary resuscitation, and haemoglobin level. The area under the receiver operating curve (AUC) for the DAS was 0.77 (95% CI 0.72-0.82) compared with the GAS with an AUC of 0.72 (95% CI 0.67-0.77). The DAS showed a death rate in patients with a predicted death rate ≥80% of 83%.

CONCLUSIONS

The present study shows that the DAS has a higher discriminative performance (AUC) compared with the GAS. All clinical variables used for the DAS are easy to obtain. Identification of low risk patients with the DAS can potentially reduce turndown rates. The DAS can reliably be used by clinicians to make a more informed decision in dialogue with the patient and their family whether or not to proceed with surgical intervention.

Long-Term Results of Local Thrombolysis Followed by First Rib Resection: An Encouraging Clinical Experience in Treatment of Subclavian Vein Thrombosis

The purpose of this study was to present the long-term results of our experience, which includes thrombolysis, surgical decompression, and long-term anticoagulation. The medical records of 24 patients who were admitted to Academic Hospital Vrije Universiteit, Amsterdam, the Netherlands, between January 1983 and October 1997, with effort thrombosis of the subclavian vein were reviewed. There were 21 men and 3 women, with a mean age of 30.5 years and an average duration of the symptoms of 2.9 days. Clinical diagnosis was confirmed by phlebography and duplex in all patients. A loading dose of 10,000 units streptokinase was given followed by an infusion at a rate of 10,000 units per hour. Phlebography was repeated daily in order to evaluate the effect of the treatment. Thrombolysis was achieved in 2 to 8 days (mean 5 days). After achievement of complete thrombolysis, anticoagulation with heparin and coumarin derivatives was started; the latter were continued for 3 months.

Six to 12 weeks after the thrombolysis, patients with costoclavicular compression syndrome underwent surgery. A transaxillary first rib resection, partial scalenotomy, and transection of the tendon of subclavian muscle were performed. Thrombolysis was achieved in all patients but one, with a successful lysis percentage of 95.8%. In one patient, the local streptokinase therapy had to be discontinued because of pulmonary embolism. Resection of the first rib was performed on 19 patients. Two patients refused to be operated on. The other three were lost to follow-up, right after the thrombolytic therapy. In long-term evaluation, all the patients who underwent first rib resection were symptom free, whereas the two patients who refused to be operated on had pain and discoloration of the affected arm, although venous patency was achieved.

The subclavian vein thrombosis occurs as a result of repetitive trauma due to anatomic constriction of the vein by the clavicle and the first rib complex. Therefore, we advise addressing the therapy not only to the superimposed thrombus but also to the correction of the underlying anatomic abnormality.

Quality of life from a randomized trial of open and endovascular repair for abdominal aortic aneurysm

Background

Long-term survival is similar after open or endovascular repair of abdominal aortic aneurysm. Few data exist on the effect of either procedure on long-term health-related quality of life (HRQoL) and health status.

Methods

Patients enrolled in a multicentre randomized clinical trial (DREAM trial; 2000–2003) in Europe of open repair versus endovascular repair (EVAR) of abdominal aortic aneurysm were asked to complete questionnaires on health status and HRQoL. HRQoL scores were assessed at baseline and at 13 time points thereafter, using generic tools, the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36®) and EuroQol 5D (EQ-5D™). Physical (PCS) and mental component summary scores were also calculated. Follow-up was 5 years.

Results

Some 332 of 351 patients enrolled in the trial returned questionnaires. More than 70 per cent of questionnaires were returned at each time point. Both surgical interventions had a short-term negative effect on HRQoL and health status. This was less severe in the EVAR group than in the open repair group. In the longer term the physical domains of SF-36® favoured open repair: mean difference in PCS score between open repair and EVAR −1·98 (95 per cent c.i. −3·56 to −0·41). EQ-5D™ descriptive and EQ-5D™ visual analogue scale scores for open repair were also superior to those for EVAR after the initial 6-week interval: mean difference −0·06 (−0·10 to −0·02) and −4·09 (−6·91 to −1·27) respectively.

Conclusion

In this study EVAR appeared to be associated with less severe disruption to HRQoL and health status in the short term. However, during longer-term follow-up to 5 years, patients receiving open repair appeared to have improved quality of life and health status.

Rationale and design of the EAGLE Registry: EVAR with Endurant® in challenging anatomy

AIM

The aim of this study was to collect clinical information on the performance of the Endurant® (II) Stent Graft System for endovascular repair in anatomically challenging infrarenal aneurysms, and to critically assess whether the current instructions for anatomic eligibility for endovascular treatment with this system are still applicable.

METHODS

Initiated by doctors, EAGLE is a prospective, non-interventional study, aiming to enrol 250 patients in 20 experienced centres across several countries worldwide. EAGLE focuses on patients with challenging angulation or neck length. To minimize the risk of selection bias and enhance data quality, EAGLE eligibility will be determined by an independent core-lab and efforts will be made to secure consecutive enrolment of challenging cases. The EAGLE database is designed to merge with the on-going ENGAGE database, which enables comparative analysis of cases and results.

RESULTS

The primary endpoint is treatment success at 30 days, 12 months and yearly up to 5 years postimplant.

CONCLUSION

Separate studies on the performance of EVAR in challenging anatomy are necessary to demonstrate safety and effectiveness of the latest generation stent-grafts, which is essential in making a balanced judgment about the optimal management of AAAs.

Effect of regional cooperation on outcomes from ruptured abdominal aortic aneurysm

BACKGROUND

Care for patients with a ruptured abdominal aortic aneurysm (rAAA) in the Amsterdam ambulance region (The Netherlands) was concentrated into vascular centres with a 24-h full emergency vascular service in cooperation with seven referring regional hospitals. Previous population-based survival after rAAA in the Netherlands was 46 (95 per cent confidence interval (c.i.) 43 to 49) per cent. It was hypothesized that regional cooperation would improve survival.

METHODS

This was a prospective observational cohort study carried out simultaneously with the Amsterdam Acute Aneurysm Trial. Consecutive patients with an rAAA between 2004 and 2011 in all ten hospitals in the Amsterdam region were included. The primary outcome was 30-day survival after admission. Multivariable logistic regression, including age, sex, co-morbidity, intervention (endovascular or open repair), preoperative systolic blood pressure, cardiopulmonary resuscitation and year of intervention, was used to assess the influence of hospital setting on survival.

RESULTS

Of 453 patients with rAAA from the Amsterdam ambulance region, 61 did not undergo intervention; 352 patients were treated surgically at a vascular centre and 40 at a referring hospital. The regional survival rate was 58.5 (95 per cent c.i. 53.9 to 62.9) per cent (265 of 453). After multivariable adjustment, patients treated at a vascular centre had a higher survival rate than patients treated surgically at a referring hospital (adjusted odds ratio 3.18, 95 per cent c.i. 1.43 to 7.04).

CONCLUSION

After regional cooperation, overall survival of patients with an rAAA improved. Most patients were treated in a vascular centre and in these patients survival rates were optimal.

Cost-effectiveness and cost–utility of endovascular versus open repair of ruptured abdominal aortic aneurysm in the Amsterdam Acute Aneurysm Trial

Background

Minimally invasive endovascular aneurysm repair (EVAR) could be a surgical technique that improves outcome of patients with ruptured abdominal aortic aneurysm (rAAA). The aim of this study was to analyse the cost-effectiveness and cost–utility of EVAR compared with standard open repair (OR) in the treatment of rAAA, with costs per 30-day and 6-month survivor as outcome parameters.

Methods

Resource use was determined from the Amsterdam Acute Aneurysm (AJAX) trial, a multicentre randomized trial comparing EVAR with OR in patients with rAAA. The analysis was performed from a provider perspective. All costs were calculated as if all patients had been treated in the same hospital (Onze Lieve Vrouwe Gasthuis, teaching hospital).

Results

A total of 116 patients were randomized. The 30-day mortality rate was 21 per cent after EVAR and 25 per cent for OR: absolute risk reduction (ARR) 4·4 (95 per cent confidence interval (c.i.) –11·0 to 19·7) per cent. At 6 months, the total mortality rate for EVAR was 28 per cent, compared with 31 per cent among those assigned to OR: ARR 2·4 (−14·2 to 19·0) per cent. The mean cost difference between EVAR and OR was €5306 (95 per cent c.i. –1854 to 12 659) at 30 days and €10 189 (−2477 to 24 506) at 6 months. The incremental cost-effectiveness ratio per prevented death was €120 591 at 30 days and €424 542 at 6 months. There was no significant difference in quality of life between EVAR and OR. Nor was EVAR superior regarding cost–utility.

Conclusion

EVAR may be more effective for rAAA, but its increased costs mean that it is unaffordable based on current standards of societal willingness-to-pay for health gains.

Randomized clinical trial of donor-site wound dressings after split-skin grafting

Background

The aim was to study which dressing material was best for healing donor-site wounds (DSWs) after split-skin grafting as there is wide variation in existing methods, ranging from classical gauze dressings to modern silicone dressings.

Methods

This 14-centre, six-armed randomized clinical trial (stratified by centre) compared six wound dressing materials in adult patients with DSWs larger than 10 cm2. Primary outcomes were time to complete re-epithelialization and pain scores measured on a visual analogue scale (VAS) over 4 weeks. Secondary outcomes included itching (VAS, over 4 weeks), adverse events and scarring after 12 weeks rated using the Patient and Observer Scar Assessment Scale (POSAS).

Results

Between October 2009 and December 2011, 289 patients were randomized (of whom 288 were analysed) to either alginate (45), film (49), gauze (50), hydrocolloid (49), hydrofibre (47) or silicone (48) dressings. Time to complete re-epithelialization using hydrocolloid dressings was 7 days shorter than when any other dressing was used (median 16 versus 23 days; P &lt; 0·001). Overall pain scores were low, and slightly lower with use of film dressings (P = 0·038). The infection rate among patients treated with gauze was twice as high as in those who had other dressings (18 versus 7·6 per cent; relative risk 2·38, 95 per cent confidence interval 1·14 to 4·99). Patients who had a film dressing were least satisfied with overall scar quality.

Conclusion

This trial showed that use of hydrocolloid dressings led to the speediest healing of DSWs. Gauze dressing should be discontinued as they caused more infections. Registration number: NTR1849 (http://www.trialregister.nl).

Primary subclavian vein thrombosis and its long-term effect on quality of life

We aimed to compare the long-term results of three different strategies for treatment of patients with primary (spontaneous or effort related) subclavian vein thrombosis (PSVT). We followed 45 consecutive patients who had been treated for PSVT receiving either oral anticoagulant therapy only ( n = 14, group 1); thrombolysis followed by anticoagulant therapy ( n = 14, group 2); or thrombolysis, transaxillary first rib resection and anticoagulant therapy ( n = 17, group 3). Endpoints were persisting symptoms and quality of life (QoL). The latter was assessed with the EuroQol (EQ-5D) questionnaire at the end of follow-up. The design is a case-control study with three different groups. Predictors for residual symptoms and QoL were analyzed with logistic and linear regression analysis. Patients in groups 2 and 3 had significantly less pain, swelling and fatigue in the afflicted limb at six weeks. There was no difference in pain ( P = 0.90), swelling ( P = 0.58), fatigue ( P = 0.61), functional impairment ( P = 0.61), recurrence ( P = 0.10) or QoL ( P = 0.25) between groups at the end of follow-up (mean follow-up 57 months [range 2–176, SD ± 46]). Treatment strategy was not predictive of QoL ( P = 0.91, analysis of variance). No differences in long-term symptoms or QoL between patients with successful and unsuccessful thrombolysis were present. In conclusion, thrombolysis with or without first rib resection does not appear to contribute to lasting symptom reduction and improvement of QoL in this study. The effect of thrombolysis may be limited to short-term symptom relief. Transaxillary first rib resection was not associated with improved late outcome (symptoms, QoL) and did not reduce recurrence rate.

Aortic aneurysm and orchitis due to Wegener's granulomatosis

We present a patient with Wegener's granulomatosis (WG) with involvement of the abdominal aorta, testis, peripheral nerve system, and skin. A 51-year-old man presented at our outpatient clinic with lower back pain. He had a history of smoking, hypertension, and an embryonal carcinoma of the left testis, treated 13 years ago with orchidectomy and chemotherapy. One month earlier, he underwent a partial orchidectomy of the right testis due to testicular swelling. Abdominal computed tomography showed a 3.8 cm wide aneurysm of the distal part of the aorta with inflammation. One week later he was admitted to the hospital with numbness of his hands and feet. Physical examination showed signs of peripheral microemboli. Serological laboratory tests revealed elevated antineutrophil cytoplasmic antibody titers with positive reactions against proteinase-3, indicating Wegener's disease. The chest X-ray was normal. Pathological examination of the right testis showed necrotizing vasculitis of a small artery. He was treated with cyclophosphamide and prednisolone. WG with extrapulmonary involvement occurs infrequently, and reports of manifestations of WG in aorta, testis, the peripheral nerve system, and skin are even more uncommon. Small- and medium-vessel vasculitis can precede large-vessel vasculitis or occur in the absence of small-vessel involvement. Therefore, WG should be included in the work-up of large-vessel vasculitis, which can give rise to periaortic inflammation.

Wound healing: total contact cast vs. custom-made temporary footwear for patients with diabetic foot ulceration

The objective of this study was to compare the effectiveness of irremovable total-contact casts (TCC) and custom-made temporary footwear (CTF) to heal neuropathic foot ulcerations in individuals with diabetes. In this prospective clinical trial, 43 patients with plantar ulcer Grade 1 or 2 (Wagner scale) were randomized to one of two off-loading modalities: TCC or CTF. Outcomes assessed were wound surface area reduction (cm2) and time to wound healing (days) at 2, 4, 8 and 16 weeks. To evaluate safety, possible side effects were recorded at each follow-up visit. The results showed no significant difference in wound surface area reduction (adjusted for baseline wound surface) at 2, 4, 8 or 16 weeks (adjusted mean difference 0.10 cm2; 95% CI -0.92-0.72 at 16 weeks). At 16 weeks, 12 patients had a completely healed ulcer, 6 per group. The median time to healing was shorter for the patients using a cast (52 vs. 90 days, p = 0.26). Five patients with TCC and two with CTF developed device-related complications. It was concluded that: (i) the rate of wound healing is not significantly different for patients treated with CTF or TCC. The difference in wound surface area was small and not significant at any time during follow-up; and (ii) the difference in healing time (38 days) may have attained statistical significance if the numbers in these sub-groups (2 x 6) had been higher. Since there appears to be little difference in effectiveness between both off-loading modalities, further investigation into the benefits of CTF is warranted.

Meta-analysis and systematic review of the relationship between volume and outcome in abdominal aortic aneurysm surgery (Br J Surg 2007; 94: 395–403)

The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses should be sent electronically via the BJS website (www.bjs.co.uk). All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length.

[Endovascular prostheses and extra-anatomical bypasses to mesenteric and renal vessels in a patient with a thoraco-abdominal aortic aneurysm: a possible alternative to the standard operation]

A 57-year-old male had a thoraco-abdominal aortic aneurysm that was increasing in diameter, accompanied by pain in the right lower abdomen and groin. Ten years earlier he had had a dissecting thoraco-abdominal aneurysm that extended from the left subclavian artery to the aortic bifurcation. A CT-scan revealed further growth of the aneurysm. He was treated by an open and an endovascular operation. The distal aorta was replaced by a bifurcation prosthesis via a laparotomy, with 2 other bifurcation prostheses to 2 mesenteric and 2 renal arteries. In a second session, a carotid-subclavian bypass was constructed and the aorta was reinforced by an endograft from the left subclavian artery to the bifurcation prosthesis. Postoperatively he suffered a transient ischaemic attack, hypertension, pneumonia, and vocal cord paresis. At follow-up 1.5 years later, the patient was free of symptoms, with the exception of slight hoarseness during forced speech, and the aneurysm was totally under control. This procedure may be an alternative to the classical thoracophrenicolaparotomy.

Relation between hospital volume and outcome of elective surgery for abdominal aortic aneurysm: a systematic review

OBJECTIVES

Our aim was to analyse the relation between hospital volume and peri-operative mortality in abdominal aortic aneurysm surgery.

DESIGN

Systematic review.

METHOD

The Medline, Embase and Cochrane databases were searched to identify all population based studies reporting on the volume outcome relationship published between 1966 and 2006. Two independent observers performed methodological quality assessment and data extraction. Outcome was 30-day or in-hospital mortality in relation to hospital volume.

RESULTS

Twenty-four articles were included. Overall peri-operative mortality ranged from 2.3 to 9.9%. The cut-off values for a high- or low-volume hospital appeared to range from 8 to 50 operations annually. The peri-operative mortality in low volume hospitals (LVH) ranged from 3.0 to 13.8% (median 6.2%) and from 1.8 to 7.4% in high volume hospitals (HVH) (median 4.3%). In 14 studies a significantly lower mortality was found in HVH as opposed to LVH; in 10 articles no such difference between HVH and LVH could be proved.

CONCLUSION

We found some evidence for a relation between the volume of AAA surgery and peri-operative mortality. There seems to be a nonsignificant trend in favour of high volume hospitals. However we could not derive an unequivocal volume threshold for safely performing AAA surgery.

Can transcutaneous oxygen tension measurement determine re-amputation levels?

OBJECTIVE

To review the preoperative transcutaneous oxygen tension (TcPO2) measurements in patients having major lower leg amputation, and also consider the re-amputation rate, wound infection and the definitive level of amputation.

METHOD

A case-control study was performed in a consecutive cohort of 170 patients (1999-2003). Fifty-two patients underwent preoperative TcPO2 measurements (cases) and 118 patients did not (control). Multiple logistic regression analysis was performed to analyse independent risk factors associated with re-amputations.

RESULTS

Primary and definitive (in case of a re-amputation) amputation levels were lower in the TcPO2 group, although this did not reach statistical significance. The number of re-amputations in the TcPO2 group was significantly higher: 15 versus 18 patients (p=0.039). Selection of an amputation level with aTcPO2 of 30mmHg resulted in a positive predictive value of re-amputation of 41% and a negative predictive value of 90%. A cut off value of 20mmHg resulted in 41% and 77% respectively.

CONCLUSION

The use of TcPO2 measurements for major amputation level selection resulted in an increased rate of re-amputation. However, there was a trend in gaining a more distal definitive amputation level. Selection of an amputation level solely based on a TcPO2 value is unreliable.

[The guideline 'Diagnosis and treatment of peripheral artery disease of the lower extremities' of The Netherlands Surgical Society]

The guideline 'Diagnosis and treatment of peripheral artery disease of the lower extremities' describes the diagnostic work-up and treatment of patients with peripheral artery disease of the legs. The text is the result of a cooperative effort of the Dutch Society of Vascular Surgery and the Section of nterventional Radiology of the Dutch Society of Radiology. A diagnosis of 'peripheral artery disease' can be made by measuring the ankle/brachial index. Additional investigations are only necessary ifa plan for invasive treatment must be drawn up. The first line of treatment in patients with intermittent claudication is walking exercise. If the results are unsatisfactory, percutaneus transluminal angioplasty (PTA) or surgery can be performed. In case of critical ischaemia, revascularisation is mandatory to prevent an amputation. In selected cases, percutaneous intentional endovascular revascularisation is a good alternative to bypass surgery. In patients with acute ischaemia in whom the vitality of the leg is not threatened, intra-arterial thrombolysis can be carried out as an alternative to surgery. An inhibitor of platelet aggregation such as acetylsalicylic acid and a statin should be prescribed to patients with peripheral artery disease. Only in case of venous bypass surgery should a coumarin derivative and a statin be prescribed for 2 years, while the bypass is controlled periodically for 6 months by duplex examination.

Mid-term Survival and Costs of Treatment of Patients with Descending Thoracic Aortic Aneurysms; Endovascular vs. Open Repair: a Case-control Study

OBJECTIVES

To evaluate the results of open surgery or endovascular stent graft repair of descending thoracic aortic aneurysm (TAA).

DESIGN, MATERIALS AND METHODS

This is a retrospective multicenter study of 95 patients undergoing TAA repair (42 stent grafts, 53 open repair). The median age was 67 years. Post-operative complications, mid-term survival and costs were assessed. The results were pooled with data in the literature.

RESULTS

After a mean follow up of 26 months (open group) and 15 months (endovascular group) survival was similar for patients treated by either repair method. Post-operative pneumonia was more in the open group (p <0.02). The hospital costs of open treatment were 40% more than that of the endovascular procedure. Combining the present results with pooled data from the literature the peri-operative mortality and paraplegia rate was less in the endovascular group (p <0.05).

CONCLUSIONS

These retrospective data suggest that endografting of descending thoracic aneurysms can be performed with less peri-operative morbidity, at lower hospital costs, but with equal mid-term life expectancy, compared with open grafting.

[Determinants of hospital mortality in surgical patients aged 80 years and over]

OBJECTIVE

To determine prognostic factors associated with mortality in patients aged 80 years and over who were treated at the Department of Surgery within a one-year period.

DESIGN

Prospective.

METHOD

The following items from the complications register were investigated: degree of mobility prior to the operation and the housing circumstances, presence of comorbidity in the case history (heart disease, lung disease, diabetes mellitus, dementia, urgency of admission and operation (elective, urgent, acute)), and the surgical subspecialism (gastroenterology, traumatology, vascular surgery and general surgery). The number of postoperative complications was also examined. Statistical analyses were performed using the chi 2 test and multiple logistic regression analysis.

RESULTS

A total of 179 patients were included: 53 men and 126 women, with an average age of 85 years and 86 years respectively. The overall mortality was 11%: 39% in acutely presented patients and 8% in subacute patients. None of the electively operated patients died. The following factors were significantly associated with mortality: subacute presentation (odds ratio 8.5; 95%-CI: 2.8-27), acute presentation (odds ratio 72; 95%-CI: 8-737), cardiological evaluation without further measures was associated with less mortality (odds ratio 0.13; 95%-CI: 0.02-0.85).

CONCLUSION

The risk of mortality increased with the urgency of presentation. A cardiological evaluation in which the patient, without the need for further additional measures, was found to be in an optimal condition was associated with a relatively low risk of mortality.

Genetic linkage of candidate genes in families with abdominal aortic aneurysms?

OBJECTIVES

to examine possible involvement of several candidate genes in the aetiology of familial abdominal aortic aneurysm (AAA).

DESIGN

after reviewing the literature on the genetics of familial AAA, betaine homocysteine methyltransferase (BHMT), collagen type Ialpha2 (COL1A2) and cathepsin H (CTSH), were selected as potential candidate genes, which influence structure, strength, elasticity and mechanical resistance of the aortic wall.

MATERIALS

forty-eight families with 110 family members and AAA were included in the affected sib-pair analysis. One large family of three generations was analysed separately because in this family also other clinical symptoms were involved.

METHODS

genetic linkage analysis was performed with DNA markers in the region of BHMT, COL1A2 and CTSH.

RESULTS

In the overall sib-pair analysis, the LOD scores for BHMT, COL1A2 and CTSH were 0.7, 0.2 and -0.7, whereas in the large family these numbers were -0.6, -2.2 and -2.7, respectively.

CONCLUSIONS

none of the candidate genes selected showed a suggestive linkage with AAA. Exclusion of the COL1A2 and CTSH genes was possible in the large family that was analysed separately.

Endoluminal aortic shunting for distal perfusion during thoracic aortal cross-clamping in a pig model

PURPOSE OF THE STUDY

To investigate the haemodynamic properties of a direct endovascular aortic shunt to maintain distal aortic perfusion as an alternative of a distal shunt (left-left-, Gott shunt) in thoracic aortic aneurysm repair.

METHODS

A shunt was developed and tested in an in vitro model which should be capable of transporting a flow of 3-4 L/min with a decrease in blood pressure < 20 mmHg. Thereupon the shunt was tested in an in vivo experiment in six pigs to assess the possibility of its use with normal distal blood pressure. The shunt was inserted in the thoracic aorta and stayed in place for 1.5 h. Parameters were measured at six time intervals to assess organ perfusion, -function, cardiac output, proximal- and distal blood pressure and aortic- and shunt flow.

PRINCIPLE FINDINGS

The mean blood flow through the shunt was 2.5 L/min. The difference of the mean blood pressure over the shunt was on average 14.20 mmHg. Parameters for coagulation disturbance and organ ischaemia were tested. The decrease in mean thrombocyte count was 299-158 (p<0.02). The venous lactate and the venous mesenteric lactate as parameters for intestinal ischemia did not increase significantly. No significant changes occurred in angiotensin II levels. Pulsatile flow was maintained but significantly suppressed (60%) distal from the shunt. The clamp time needed to insert the shunt and the venous mesenteric lactate, as well as the venous lactate, showed high correlation, r(s) = 0.9 (p<0.05) and r(s) = 0.94 (p<0.01). This also accounted for the 2nd clamp time, both r(s) = 0.95 (p<0.05).

CONCLUSION

The shunt is capable of transporting a blood flow of 2-4 L/min with an acceptable decrease in distal blood pressure. However, the time, needed to insert the shunt, was significantly associated with parameters of organ ischaemia.

The effect of inhibition of renin-angiotensin system by valsartan during hypovolemic shock and low flow sigmoideal ischaemia in pigs

The aim of this experiment was to study the effect of Renin-Angiotensin System (RAS) blockade by means of valsartan on the colonic and systemic circulation in pigs during low flow sigmoideal ischemia in combination with hypovolemic shock. This condition resembles the situation that occurs in patients suffering from a ruptured aneurysm and a compromised colonic circulation. An experimental study in pigs was performed : 6 pigs with low flow sigmoideal ischemia and hypovolemic shock were treated with valsartan and a control group of 5 pigs with low flow sigmoideal ischemia and hypovolemic shock without medical treatment.Valsartan, 3 mg/kg, was administered intravenously. The operation was performed via left sided lumbotomy. The distal aorta was partially occluded to a flow reduction of 30% of the initial value. Hypovolemic shock was induced by withdrawing 20 ml/kg blood in 45 min. Resuscitation with 30 ml/kg haemaccel was iniated after 2 h of shock. The following parameters were measured: blood pressure, cardiac output; hemoglobin, lactate, angiotensin II in mixed venous blood (obtained from pulmonary artery) and in splanchnic blood (obtained from caudal mesenteric vein); and endoluminal pulse oximetry of the sigmoideal mucosa. Statistical analysis was performed by ANOVA and Wilcoxon signed rank test. There was a significant increase of lactate levels both in systemic and splanchnic circulation (P<0.05) in both groups. In the control group, the mean angiotensin II concentrations in the systemic circulation increased, after induction of ischaemia and shock. In the experimental group, the increase in angiotensin concentrations after resuscitation was significantly more prominent. In the colonic circulation, in both groups, there was a significant increase in angiotensin II levels in the splanchnic circulation following ischaemia and reperfusion (P<0.05), but there was no significant difference between the groups. There were no detectable mucosal signals measured by pulse oximetry after induction of shock throughout the experiment, whereas in the experimental group, median mucosal oxygen saturations of 81, 74.5 and 85% were achieved after resuscitation and declamping (P<0.01).In conclusion, angiotensin II inhibition during hypovolemic shock improves the colonic circulation, measured by pulse oximetry. However, other parameters of tissue ischaemia did not improve.

[Safety regarding invasive procedures in HIV-positive patients]

A 46-year-old man and a 58-year-old man, both known for several years with HIV infection, were admitted for operations due to aortic valve insufficiency (aortic valve replacement) and posttraumatic coxarthrosis (total hip replacement) respectively. In accordance with the protocol, preoperative viral infections (HIV, hepatitis B and C) were inventoried, the HIV viral load was lowered medicinally and the operation team informed. During each operation a consultant was present in the operating theatre to provide advice in the case of a needlestick or cut accident. No accidents occurred. Both patients were discharged to home in a good condition.

[Endovascular treatment of 2 patients with an aneurysm of the descending thoracic aorta]

Two men, aged 71 and 70, who had previously experienced an abdominal aneurysm were found to have thoracic aortal aneurysms of respectively 8 cm and 7.5 cm in length. For the first patient an endovascular operation was carried out due to a high operative risk: with the help of a radiograph, four endoprostheses were inserted into the thoracic descending aorta via the femoral artery, after which the aorta diameter became more normal. A month later, the patient died from persistent renal failure, which had developed as a result of the previously ruptured abdominal aneurysm. In the second patient with an aneurysm of the proximal descending aorta, a left decompensation arose following aortal clamping during open surgical repair. Ten weeks later an endoprosthesis was inserted via the femoral artery. A year later the aortal diameter had decreased to 6.5 cm; the patient functioned well. The insertion of an endoprosthesis in the thoracic aorta is a minimally invasive procedure in which the patient experiences little perioperative inconvenience.

Endoluminal pulse oximetry of the sigmoid colon and the monitoring of the colonic circulation

Colonic ischaemia is a frequently observed serious complication following abdominal aortic reconstruction. For adequate treatment of this disorder, early diagnosis and resection of the diseased colon is essential. The purpose of this study was to evaluate a new method, based on pulse oximetry, to detect colonic ischaemia at an early preclinical stage. During a 7-year period (1989-1995) colonoscopy and pulse oximetry were performed in all patients at risk of colonic ischaemia: complicated acute or elective aortic reconstructions, colostomies with superficial necrosis and in patients who underwent uncomplicated aortic reconstruction and non-ischaemic colonic problems (n = 90). The sensitivity, specificity and positive predictive values, and negative predictive value, were calculated. All patients, except four for whom an acute relaparotomy was necessary, subsequently underwent colonoscopy combined with endoluminal pulse oximetry. Of the 90 patients, 30 had colonic ischaemia according to endoscopy (n = 26) or relaparotomy (n = 4), and in 33 patients the absence of pulsatile signal was detected by means of pulse oximetry. Thus, in three patients, pulse oximetry was falsely positive for colonic ischaemia. The calculated sensitivity and specificity of pulse oximetry were 100 and 95%, respectively. In comparison to other methods used for early detection of colonic ischaemia, pulse oximetry appears to be a promising method for the evaluation and monitoring of colonic ischaemia because it is non-invasive and easy to apply with a high sensitivity and specificity.

The renin-angiotensin system in swine during hypovolaemic shock combined with low-flow ischaemia of the sigmoid colon

Colonic ischaemia is a serious complication after aortic surgery, and is most frequent after repair of ruptured aortic aneurysms. It was felt that the increased risk of colonic ischaemia during shock might be the result of a local effect of the renin-angiotensin system in the splanchnic circulation, which is exacerbated by poor perfusion. In order to evaluate the activity of the renin-angiotensin system in the colonic circulation, a subtotal occlusion of the distal aorta was induced in nine pigs. A colonic flow reduction of 70% was created for 4 hours. In the experimental group (n = 6), induce hypovolaemic shock, 20 cm3/kg blood was sampled at 45 min before resuscitation was performed with 20 cm3/kg haemaccel. The sham group (n = 3) did not have hypovolaemic shock induced. Blood samples were taken for determinations of angiotensin II, haemoglobin and lactate. Blood gas was obtained from the pulmonary artery and the caudal mesenteric vein for blood gas analysis and lactate determinations. ANOVA and the Wilcoxon sum rank test were used for statistical analysis. There was a significant increase in angiotensin II after induction of ischaemia in both groups. The increase in angiotensin II in the splanchnic circulation was more prominent than the increase in the systemic circulation (P < 0.01). In the experimental group, there was a sustained increase in angiotensin II levels in the splanchnic circulation following shock and reperfusion (P < 0/01). The increase in lactate concentrations, which was significantly higher in the experimental group (P < 0.05), was evidence of intestinal ischaemia. There was a significant decline in cardiac output and blood pressure during the period of shock (P < 0.05). The combination of colonic ischaemia and hypovolaemic shock followed by reperfusion leads to an increase in angiotensin II activity. The increase of the local activity of the renin-angiotensin system in the splanchnic circulation is more prominent after ischaemia and reperfusion. This is probably caused by a selective response of the splanchnic vasculature to shock, ischaemia and reperfusion.

Risk factors for premature atherosclerosis

OBJECTIVES

to investigate the prevalence of risk factors in patients with premature atherosclerosis.

DESIGN

retrospective controlled study.

MATERIALS

135 consecutive patients with premature atherosclerosis </= 55 years (group I) were investigated. A control group comprised 107 consecutive patients >/= 65 years (group II) with atherosclerosis. Statistical analysis was performed with Chi-squared test and logistic regression analysis.

RESULTS

group I versus group II: diabetes 11% vs. 27% (p=0.001), smoking 84% vs. 67% (p=0.002), hypertension 36% vs. 58% (p=0.001), hypercholesterolaemia 47% vs. 34% (p=0.04), family history of cardiovascular disease 53% vs. 42% (p=0.08). In group I hyperhomocysteinaemia was present in 24 of the 108 patients tested, anticardiolipin antibodies were present in four of the 34 tested and coagulation abnormalities were found in four of the 22 patients tested.

CONCLUSION

the difference in the prevalence of the different risk factors between the two groups suggests that either certain risk factors are more likely to cause premature atherosclerosis, or that other risk factors must be present in addition to the known risk factors in order to induce premature atherosclerosis.

Reconstruction of the supra-aortic trunks

OBJECTIVE

To review our 10-year experience of reconstruction of the supra-aortic trunks.

DESIGN

Retrospective study.

SETTING

Teaching hospital, The Netherlands.

SUBJECTS

47 patients who required reconstruction of the supra-aortic trunks for stenotic or occlusive disease between April 1987 and May 1997.

INTERVENTIONS

Right-sided bifurcation graft through a sternotomy (n = 25), left-sided thoracotomy (n = 1), and extra-anatomic bypass (n = 21).

MAIN OUTCOME MEASURES

Morbidity, mortality, and long term patency.

RESULTS

3 patients died (6%); 7 (15%) developed major complications (leak from the brachiocephalic stump, n = 2, and acute occlusion of the bypass graft, n = 5) all of which were successfully treated by immediate reoperation; and 9 (19%) developed minor complications, all of which resolved within 3 months. The median follow up was 36 months (range 1-108), and the 3-year patency rate was 80%. No patient died during the follow up period, but a further 3 were lost to follow up. The remaining 41 were all assessed by duplex scanning or angiography, and 3 required further operation for recurrent symptoms; 33 remained completely free of symptoms.

CONCLUSION

Symptomatic stenotic or occlusive lesions of the supra-aortic trunks can be treated with acceptable morbidity and mortality, giving long term benefit to patients.

The visceral perfusion system and distal bypass during thoracoabdominal aneurysm surgery: an alternative for physiological blood flow?

There are potential benefits to addition of visceral organ perfusion, by means of a 9-Fr. catheter system (octopus), to distal aortic perfusion during thoracoabdominal aneurysm surgery. However, in the literature there are reports of adverse effects. The authors therefore compared two groups of patients who underwent thoracoabdominal aneurysm surgery with and without visceral organ perfusion. In the group in which the visceral perfusion was applied, the use of platelets (26 versus 11 units; P < 0.05), fresh frozen plasma (3.4 versus 1.5 units; P < 0.05) and packed cells (20 versus 8 units, P < 0.05) was significantly increased. An equal number of patients in both groups developed renal failure postoperatively. An explanation for this adverse effect can be found in the high shear rates in the catheters used, mainly as a result of the small diameter. High shear rates cause haemolysis. Also, the flow through the catheters is insufficient to maintain adequate perfusion of the visceral organs. A higher flow in these catheters would result in an even higher shear rate. It is therefore concluded that coagulopathy and insufficient bloodflow is caused by the small internal diameter of the catheters, which renders the device insufficient.

[Nothing gained from the determinations of plasma lactate levels in the evaluation of a patient with acute abdomen]

OBJECTIVE

To establish the diagnostic value of laboratory tests, especially the plasma lactate concentration, for determination of the indication for acute surgery in patients with an acute abdomen.

DESIGN

Cross-sectional study.

SETTING

Kennemer Gasthuis, location Elisabeth Gasthuis, Haarlem, the Netherlands.

METHOD

The study group consisted of all 200 successive patients presenting at the emergency room with acute abdomen from June 1993 to December 1994 (19 months). Patients with suspected acute appendicitis were excluded. The diagnosis and indication for surgery if any were based on case history, physical examination, radiological examination if performed and standard laboratory tests: ESR, leukocyte count, haemoglobin, creatinine and amylase. The first matter considered was to what extent the indication for acute operation based on these clinical criteria was in agreement with the diagnosis at discharge. The next question studied was what would be the extra value of the plasma lactate concentration which, although determined, had not been reported to the clinician. Statistical analysis was performed using the two-sample Student t test and the chi 2 test. A p-value of < 0.05 was regarded as statistically significant.

RESULTS

Fifty-four patients were operated within 24 hours for good reasons, six were incorrectly not operated within 24 hours, 128 correctly received conservative treatment and 12 were correctly treated conservatively and subsequently underwent operation after longer than 24 hours. Diagnostics based on the clinical criteria had a sensitivity of 90%. The mean plasma lactate concentration, temperature and ESR were statistically significant more often increased in the operated patients than in those treated conservatively. The sensitivities of these determinations were 75%, 67% and 40% (all: p < 0.05). The lactate concentration was increased in 50% of the patients who in retrospect had incorrectly not been subjected to acute surgery.

CONCLUSION

Neither determination of the plasma lactate concentration nor the results of the separate standard laboratory tests in acute abdomen patients resulted in a better sensitivity for the determination of an indication for acute surgery than clinical examination combined with standard laboratory tests and, if desired, supplementary radiology.

Endoluminal pulse oximetry combined with tonometry to monitor the perfusion of the sigmoid during and after resection of abdominal aortic aneurysm

Early detection of colonic ischaemia after aortic grafting is essential if mortality is to be decreased when this complication develops. The aim of this study was to determine changes in the sigmoid colon during and after abdominal aortic grafting using endoluminal pulse oximetry (SmO2). Oxygen saturation was measured on the mucosa (SmO2) and serosa (SsO2) of 20 sequential patients undergoing elective surgery for abdominal aortic aneurysm; intramural pHi was also measured. Initially, all patients had a normal SmO2 in the sigmoid; however, before cross-clamping eight patients had a reduction in the SmO2. The pulse curve disappeared immediately after cross-clamping in 15 patients, with only five still showing a pulse curve in the sigmoid colon. Before declamping, 13 patients regained their pulse curve. The intraluminal pHi showed a large interindividual variation (2 S.D. approximately 0.4). Patients were classified into three groups according to SmO2: group A, no pulse; group B, diminished saturation (< 90%); and group C, normal saturation (> or = 90%). There was significant correlation with the pHi after cross-clamping in all groups. One patient who developed ischaemia of the sigmoid colon demonstrated a prolonged reduction in the SmO2, a decreased perioperative pHi, and an increased oxygen saturation in the inferior mesenteric vein during cross-clamping.

Haemostasis during infrarenal aortic aneurysm surgery: effect of volume loading and cross-clamping

OBJECTIVES

To study thrombin and plasmin activation during elective abdominal aortic aneurysm surgery.

DESIGN

Prospective study.

SETTING

University Hospital.

MATERIALS

Nine consecutive patients undergoing elective surgery were included. The mean age was 72 years (range 60-79). Blood samples were drawn: (1) before induction of anaesthesia; (2) after induction and Swan Ganz catherisation; (3) just before cross-clamping; (4) before declamping; (5) 8 h postoperatively; (6) 18 h postoperatively.

CHIEF OUTCOME MEASURES

Assays included: prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen, prothrombin fragments (F 1 + 2), anti-thrombin III (ATIII), plasminogen, alpha 2-antiplasmin, haematocrit, platelet and serum protein for correction of haemodilution. Data were expressed as mean (S.D.). Differences between mean values were tested by means of the ANOVA for repeated measures and the Wilcoxon signed rank test.

MAIN RESULTS

The APTT and TT did not change until heparinisation. The F 1 + 2 were already elevated preoperatively. After correction for haemodilution the AT III and alpha 2-antiplasmin decreased in time (p = 0.009 and 0.0023, respectively) and the F1 + 2 increased (p < 0.0001). Postoperatively (t5 and 6) the values normalised again.

CONCLUSIONS

The coagulation and fibrinolytic systems are activated during and after elective aortic replacement. Standard tests, like the prothrombin and partial thromboplastin time, are unreliable when assessing the coagulation status of the patient.