Epidemiology, risk and prognostic factors in mesenteric venous thrombosis

BACKGROUND

Epidemiological reports on risk and prognostic factors in patients with mesenteric venous thrombosis (MVT) are scarce.

METHODS

Patients with MVT were identified through the inpatient and autopsy registry between 2000 and 2006 at Malmö University Hospital.

RESULTS

Fifty-one patients had MVT, diagnosed at autopsy in six. The highest incidence (11.3 per 100,000 person-years) was in the age category 70-79 years. Activated protein C resistance was present in 13 of 29 patients tested. D-dimer at admission was raised in all five patients tested. Multidetector row computed tomography (CT) in the portal venous phase was diagnostic in all 20 patients investigated, of whom 19 were managed conservatively. The median length of resected bowel in 12 patients who had surgery was 0.6 (range 0.1-2.2) m. The overall 30-day mortality rate was 20 percent; intestinal infarction (P = 0.046), treatment on a non-surgical ward (P = 0.001) and CT not done (P = 0.022) were associated with increased mortality. Cancer was independently associated with long-term mortality: hazard ratio 4.03, 95 percent confidence interval 1.03 to 15.85; P = 0.046.

CONCLUSION

Portal venous phase CT appeared sensitive in diagnosing MVT. As activated protein C resistance was a strong risk factor, lifelong anticoagulation should be considered.

Multicentre prospective study of fascial closure rate after open abdomen with vacuum and mesh-mediated fascial traction

BACKGROUND

Damage control surgery and temporary open abdomen (OA) have been adopted widely, in both trauma and non-trauma situations. Several techniques for temporary abdominal closure have been developed. The main objective of this study was to evaluate the fascial closure rate in patients after vacuum-assisted wound closure and mesh-mediated fascial traction (VAWCM) for long-term OA treatment, and to describe complications.

METHODS

This prospective study included all patients who received VAWCM treatment between 2006 and 2009 at four hospitals. Patients with anticipated OA treatment for fewer than 5 days and those with non-midline incisions were excluded.

RESULTS

Among 151 patients treated with an OA, 111 received VAWCM treatment. Median age was 68 years. Median OA treatment time was 14 days. Main disease aetiologies were vascular (45 patients), visceral surgical disease (57) and trauma (9). The fascial closure rate was 76·6 per cent in intention-to-treat analysis and 89 per cent in per-protocol analysis. Eight patients developed an intestinal fistula, of whom seven had intestinal ischaemia. Intestinal fistula was an independent factor associated with failure of fascial closure (odds ratio (OR) 8·55, 95 per cent confidence interval 1·47 to 49·72; P = 0·017). The in-hospital mortality rate was 29·7 per cent. Age (OR 1·21, 1·02 to 1·43; P = 0·027) and failure of fascial closure (OR 44·50, 1·13 to 1748·52; P = 0·043) were independently associated with in-hospital mortality.

CONCLUSION

The VAWCM method provided a high fascial closure rate after long-term treatment of OA. Technique-related complications were few. No patient was left with a large planned ventral hernia.

Diagnostic accuracy of plasma biomarkers for intestinal ischaemia

OBJECTIVE

Intestinal ischaemia is a life-threatening condition with high mortality, and the lack of accurate and readily available diagnostic methods often results in delay in diagnosis and treatment. The aim of this study was to investigate the accuracy of different plasma biomarkers in diagnosing intestinal ischaemia.

MATERIAL AND METHODS

Prospective inclusion of patients older than 50 years with acute abdomen admitted to hospital in Karlskrona, Sweden, between 2001 and 2003. Venous blood was sampled prior to any surgery and within 24 h from onset of pain. D-lactate, alpha glutathione S-transferase, intestinal fatty acid binding protein, creatine kinase B, isoenzymes of lactate dehydrogenase (LD) and alkaline liver phosphatase (ALP) were analysed. D-dimer was analysed using four different commercially available test kits.

RESULTS

In-hospital mortalities among patients with (n = 10) and without (n = 61) intestinal ischaemia were 40 % and 3 %, respectively (p = 0.003). D-dimer was associated with intestinal ischaemia (p = 0.001) independently of which assay was used. No patient presenting with a normal D-dimer had intestinal ischaemia. D-dimer >0.9 mg/L had a specificity, sensitivity and accuracy of 82 %, 60 % and 79 %, respectively. Total LD, isoenzymes of LD 1-4 and liver isoenzyme of ALP (ALP liver) were significantly higher in patients with intestinal ischaemia, and accuracies for LD 2 (cut-off 2.3 microkat/L) and ALP liver (cut-off 0.7 microkat/L) were 69 % and 66 %, respectively.

CONCLUSIONS

D-dimer may be used as an exclusion test for intestinal ischaemia, but lacks specificity. The other plasma biomarkers studied had insufficient accuracy for this group of patients. Further studies are needed.

Modern treatment of acute mesenteric ischaemia

BACKGROUND

Diagnosis of acute mesenteric ischaemia in the early stages is now possible with modern computed tomography (CT), using intravenous contrast enhancement and imaging in the arterial and/or portal venous phase. The availability of CT around the clock means that more patients with acute mesenteric ischaemia may be treated with urgent intestinal revascularization.

METHODS

This was a review of modern treatment strategies for acute mesenteric ischaemia.

RESULTS

Endovascular therapy has become an important alternative, especially in patients with acute thrombotic superior mesenteric artery (SMA) occlusion, where the occlusive lesion can be recanalized either antegradely from the femoral or brachial artery, or retrogradely from an exposed SMA after laparotomy, and stented. Aspiration embolectomy, thrombolysis and open surgical embolectomy, followed by on-table angiography, are the treatment options for embolic SMA occlusion. Endovascular therapy may be an option in the few patients with mesenteric venous thrombosis who do not respond to anticoagulation therapy. Laparotomy is needed to evaluate the extent and severity of visceral organ ischaemia, which is treated according to the principles of damage control surgery.

CONCLUSION

Modern treatment of acute mesenteric ischaemia involves a specialized approach that considers surgical and, increasingly, endovascular options for best outcomes.

Acute thrombo-embolic occlusion of the superior mesenteric artery: a prospective study in a well defined population

OBJECTIVES

to characterize the clinical presentation of patients with acute thrombo-embolic occlusion of the superior mesenteric artery (SMA).

DESIGN

prospective study.

MATERIALS

twenty-four consecutive patients admitted to Blekinge County Hospital, Karlskrona, Sweden, with acute thrombo-embolic occlusion of the SMA, over a three-year period from April 1999 through March 2002.

METHODS

clinical data were registered prospectively. Incidence, diagnostic procedures and factors associated with survival were analysed.

RESULTS

the diagnosis was verified at operation in 20, and at autopsy in 4 patients. The incidence was 5.3 per 100 000 inhabitants per year. Among the 20 patients with embolic disease, atrial fibrillation was present in 95%, synchronous embolic events in 30% and warfarin treatment in 10%. D-dimer was elevated on admission in 13/13. Four patients were diagnosed at first consultation. Fifteen underwent curative revascularisation (6) or bowel resection only (9). Five were alive at one-year follow-up, of whom one had short bowel syndrome. Length of bowel ischaemia predicted institutional (p = 0.004) and one-year mortality (p = 0.005).

CONCLUSIONS

the incidence was higher than expected. Embolic occlusions predominated. Old age, atrial fibrillation, severe abdominal pain and synchronous embolus suggest the diagnosis of acute bowel ischaemia. Length of bowel ischaemia predicted outcome.

Fatal nonocclusive mesenteric ischaemia: population-based incidence and risk factors

OBJECTIVES

To estimate the incidence and extension of visceral organ infarction, and to evaluate potential causes, in patients with autopsy-verified nonocclusive mesenteric ischaemia (NOMI) and transmural intestinal infarction.

SETTING

In Malmö, Sweden, the autopsy rate between 1970 and 1982 was 87%, creating possibilities for a population-based study.

DESIGN

Amongst 23 446 clinical autopsies, 997 cases were coded for intestinal ischaemia in a database. In addition, 7569 forensic autopsy protocols were analysed. In a nested case-control study within the clinical autopsy cohort, four NOMI-free controls, matched for gender, age at death and year of death, were identified for each fatal NOMI case to evaluate risk factors.

RESULTS

The overall incidence of autopsy-verified fatal NOMI was 2.0/100,000 person-years, increasing with age up to 40/100,000 person-years in octogenarians. Patients with stenosis of the superior mesenteric artery (SMA; n = 25) were older (P = 0.002) than those without (n = 37), and had more often a concomitant stenosis of the coeliac trunk (P < 0.001). Synchronous infarction in the liver, spleen or kidney occurred in one-fifth of all patients. Fatal cardiac failure [OR 2.9 (1.7-5.2)], history of atrial fibrillation [OR 2.2 (1.2-4.0)] and recent surgery [OR 3.4 (1.6-6.9)] were risk factors for fatal NOMI.

CONCLUSIONS

Fatal heart failure was the leading cause of intestinal hypoperfusion, although stenosis of the SMA and coeliac trunk, atrial fibrillation and recent surgery contributed significantly. Collaboration across specialties seems to be of utmost importance to improve the prognosis.

D-dimer testing in patients with suspected acute thromboembolic occlusion of the superior mesenteric artery

Background

There is no accurate non-invasive method available for the diagnosis of acute thromboembolic occlusion of the superior mesenteric artery (SMA). The aim of this study was to assess the diagnostic properties of the fibrinolytic marker D-dimer.

Methods

From September 2000 to April 2003 consecutive patients aged over 50 years admitted to hospital with acute abdominal pain were studied. Patients with possible acute SMA occlusion at presentation had blood samples taken within 24 h of the onset of the pain for analysis of D-dimer, plasma fibrinogen, activated partial thromboplastin time, prothrombin time and antithrombin. The value of D-dimer testing to diagnose SMA occlusion was assessed by means of likelihood ratios.

Results

Nine of 101 patients included had acute SMA occlusion. The median D-dimer concentration was 1·6 (range 0·4–5·6) mg/l, which was higher than that in 25 patients with inflammatory disease (P = 0·007) or in 14 patients with intestinal obstruction (P = 0·005). The combination of a D-dimer level greater than 1·5 mg/l, atrial fibrillation and female sex resulted in a likelihood ratio for acute SMA occlusion of 17·5, whereas no patient with a D-dimer concentration of 0·3 mg/l or less had acute SMA occlusion.

Conclusion

D-dimer testing may be useful for the exclusion of patients with suspected acute SMA occlusion.

Incidence of acute thrombo-embolic occlusion of the superior mesenteric artery--a population-based study

OBJECTIVE

To determine the incidence of acute thrombo-embolic occlusion of the superior mesenteric artery (AOSMA) in a population-based study.

MATERIAL

All clinical (n=23,446) and forensic (n=7569) autopsies performed in the city of Malmö between 1970 and 1982 (population 264,000-230,000 inhabitants). The autopsy rate was 87%.

METHODS

Calculation of the incidence of AOSMA with intestinal gangrene in those autopsies coded for bowel ischaemia (997/23,446 clinical and 9/7569 forensic autopsies). The operative procedures performed in 1970, 1976 and 1982 were also analysed.

RESULTS

Two forensic and 211 clinical autopsies demonstrated AOSMA with intestinal gangrene. Previous suspicion of intestinal ischaemia was noted in only 33%. Sixteen patients were operated. The cause-specific mortality was 6.0/1000 deaths. The incidence was 8.6/100,000 person years, increasing exponentially with age (p<0.001). Mortality was 93%.

CONCLUSIONS

The incidence and mortality of AOSMA is higher than previously reported from clinical series. There is seldom any suspicion of the diagnosis prior to death.

Endovascular therapeutic approaches for acute superior mesenteric artery occlusion

The purpose of this study was to characterize the outcome of attempted endovascular intervention in patients with acute embolic or thrombotic superior mesenteric artery (SMA) occlusion. The records of 21 patients during a 3-year period between 2005 and 2008 were retrieved from the in-hospital registry. The first group included 10 patients (6 women and 4 men; median age 78 years) with acute embolic occlusion of the SMA. The median duration of symptoms from symptom onset to angiography was 30 hours (range 6 to 120). Synchronous emboli (n = 12) occurred in 6 patients. Embolus aspiration was performed in 9 patients, and 7 of these had satisfactory results. Complementary local thrombolysis was successful in 2 of 3 patients. Residual emboli were present at completion angiography in all 7 patients who underwent successful aspiration embolectomy, and bowel resection was necessary in only 1 of these patients. One serious complication occurred because of a long SMA dissection. The in-hospital survival rate was 90% (9 of 10 patients). The second group included 11 patients (10 women and 1 man; median age 68 years) with atherosclerotic acute SMA occlusions. The median time of symptom duration before intervention was 97 hours (range 17 to 384). The brachial, femoral, and SMA routes were used in 6, 7, and 5 patients, respectively. SMA stenting was performed through an antegrade (n = 7) or retrograde (n = 3) approach. Bowel resection was necessary in 4 patients. No major complications occurred. The in-hospital survival rate was 82% (9 of 11 patients). Endovascular therapy of acute SMA occlusion provides a good alternative to open surgery.

Management of inadvertent arterial catheterisation associated with central venous access procedures

OBJECTIVE

This study aims to describe the clinical management of inadvertent arterial catheterisation after attempted central venous catheterisation.

METHODS

Patients referred for surgical or endovascular management for inadvertent arterial catheterisation during a 5-year period were identified from an endovascular database, providing prospective information on techniques and outcome. The corresponding patient records and radiographic reports were analysed retrospectively.

RESULTS

Eleven inadvertent arterial (four common carotid, six subclavian and one femoral) catheterisations had been carried out in 10 patients. Risk factors were obesity (n=2), short neck (n=1) and emergency procedure (n=4). All central venous access procedures but one had been made using external landmark techniques. The techniques used were stent-graft placement (n=6), percutaneous suture device (n=2), external compression after angiography (n=1), balloon occlusion and open repair (n=1) and open repair after failure of percutaneous suture device (n=1). There were no procedure-related complications within a median follow-up period of 16 months.

CONCLUSIONS

Inadvertent arterial catheterisation during central venous cannulation is associated with obesity, emergency puncture and lack of ultrasonic guidance and should be suspected on retrograde/pulsatile catheter flow or local haematoma. If arterial catheterisation is recognised, the catheter should be left in place and the patient be referred for percutaneous/endovascular or surgical management.

Preliminary study of D-dimer as a possible marker of acute bowel ischaemia

BACKGROUND

Occlusion of the superior mesenteric artery (SMA) demands prompt recognition and diagnosis. No accurate diagnostic method is available. The aim of this study was to determine whether the fibrinolytic marker D-dimer is a useful early marker of acute bowel ischaemia.

METHODS

Fourteen patients suspected of having acute bowel ischaemia were analysed for an increase in plasma D-dimer level.

RESULTS

Six patients had embolic or thrombotic occlusion of the SMA and all had significantly higher D-dimer levels than those without thromboembolic occlusion (P < 0.05). Four patients with strangulation of the small bowel due to adhesions and one with a ruptured aortic aneurysm also had raised D-dimer values.

CONCLUSION

In patients with suspected thromboembolic occlusive disease of the SMA, a raised level of D-dimer indicated the presence of acute bowel ischaemia, whatever the cause. A more extensive prospective study is needed to evaluate a potential survival benefit using the test as a marker of the need for urgent laparotomy.

Predictors for Outcome after Open and Endovascular Repair of Ruptured Abdominal Aortic Aneurysms

OBJECTIVES

The aims of the present study were to analyze patient- and management-related predictors for outcome after open (OR) and endovascular repair (EVAR) of ruptured abdominal aortic aneurysm (rAAA).

DESIGN

Retrospective study.

MATERIALS

The in-hospital registry of Malmö University Hospital identified 162 patients operated on due to rAAA between 2000 and 2004.

METHODS

Patient- and management-related predictors for outcome were analysed.

RESULTS

Preoperative CT in 39 out of 62 circulatory unstable patients was not associated with increased mortality (p=0.60). There was a significant increase in repairs performed by EVAR during the study period (p<0.001), and in 2004 EVAR exceeded the annual rate of OR. Patients in the EVAR group were older (p=0.025), whereas patients in the OR group more often suffered from unconsciousness after presentation (p=0.004). Age, unconsciousness after presentation and haemoglobin were significantly associated with in-hospital mortality when tested in a multivariate logistic regression model (p=0.002, p=0.003 and p<0.001, respectively). The in-hospital mortality for patients undergoing OR and EVAR was 45% (48/106) and 34% (19/56), respectively (p=0.16). Diagnosis of abdominal compartment syndrome (p=0.005) and intestinal infarction (p=0.002) was associated with poor survival.

CONCLUSIONS

Patient-related factors such as age, loss of consciousness and haemoglobin predicts outcome in a population where both emergency OR and EVAR for the treatment of rAAA is feasible.

Revascularization of the superior mesenteric artery after acute thromboembolic occlusion

BACKGROUND

The outcome and prognostic factors after revascularization of acute thromboembolic occlusion of the superior mesenteric artery (SMA) are poorly documented.

METHODS

Sixty patients with acute thromboembolic occlusion of the SMA had revascularization procedures at 21 hospitals from 1987 to 1998. They were registered prospectively in the Swedish Vascular Registry. Patient files were analysed retrospectively.

RESULTS

The median age of the patients was 76 years; 73 per cent suffered from cardiac disease and 23 per cent had previous vascular surgery. Onset of symptoms was classified as sudden (30 per cent), acute (33 per cent) or insidious (37 per cent). The occlusions were thought to be either embolic (67 per cent) or thrombotic (33 per cent). The diagnosis was suspected on first examination in 32 per cent of patients, a group whose median time to operation was shorter (P = 0.01). Fifty-eight patients had an exploratory laparotomy and subsequent revascularization, and two were treated with thrombolysis alone. Second-look laparotomy was performed in 41, and third look in eight patients; 19 required an additional bowel resection. The overall mortality rates were 43, 52, 60 and 67 per cent at 30 days, discharge, 1 and 5 years, respectively. No patient was dependent on intravenous nutrition after 1 year. Previous vascular surgery resulted in a higher institutional mortality rate (79 per cent; P = 0.02). Patients who had a sudden onset of symptoms outside hospital had a better outcome (mortality rate 27 per cent; P = 0.02).

CONCLUSION

Many non-diagnostic radiological examinations were performed and a routine second-look is warranted. The results suggest that attempts at revascularization procedures for acute mesenteric ischaemia may improve the outcome.

Incidence and risk of venous thromboembolism in patients with verified arterial thrombosis: a population study based on 23,796 consecutive autopsies

BACKGROUND

The relationship between atherothrombotic disease and venous thromboembolism (VTE) remains unclear.

PATIENTS AND METHODS

In a cohort of 23,796 consecutive autopsies, performed using a standardized procedure and representing 84% of all in-hospital deaths between 1970 and 1982 in an urban Swedish population, we investigated the relationship between verified arterial thrombosis and VTE, with the hypothesis that patients with thrombosis in major artery segments have increased odds of VTE.

RESULTS

We found an increased risk of VTE in patients with arterial thrombosis (Odds ratio; OR adjusted for gender and age 1.4, 95% confidence interval; CI 1.3-1.5) (P < 0.001). Patients with cervico-cranial and peripheral artery thrombosis had an excess risk even when controlling for age and major concomitant diseases. A negative association between coronary thrombosis and VTE in the univariate analysis (OR 0.7; 95% CI 0.6-0.8) (P < 0.001), was less pronounced in the multivariate analysis (OR 0.8; 95% CI 0.7-1.0) (P = 0.016).

CONCLUSIONS

A positive association between atherothrombosis and VTE was confirmed, except in patients with coronary thrombosis, where IHD as competing death cause is a possible confounder. Our findings indicate a potential for directed prevention, but may also imply similarities in etiology.

Maternal bone lead contribution to blood lead during and after pregnancy

We examined bone lead contribution to blood lead in a group of 311 immigrant women, 99% from Latin America, during the third trimester of pregnancy and 1 to 2 months after delivery. We measured in vivo tibia and calcaneus (heel) bone lead concentration in the postdelivery period with K shell X-ray fluorescence. Prenatal and postnatal geometric mean (range) blood lead level was 2.2 microg/dL (0.4 to 38.7) and 2.8 microg/dL (0.4 to 25.4), reflecting low current exposure. Postnatal blood lead level was significantly higher than prenatal (P<0.0001). Mean (range) tibia and calcaneus lead concentration was 6.7 microg/g (-33.7 to 62.2) and 8.4 microg/g (- 30.1 to 66.4), reflecting varying but elevated past lead exposure. Mean calcaneus lead concentration was significantly higher than mean tibia lead concentration (P = 0.055). Variance-weighted multiple regression and structural equation models showed that both calcaneus and tibia lead were directly associated with prenatal blood lead but only calcaneus lead was associated with postnatal blood lead. Increasing natural log years in the United States independently predicted decreasing calcaneus and third-trimester blood lead. The data suggest that while some exogenous lead sources and modulators of blood lead level, such as use of lead-glazed pottery and calcium in the diet, control lead exposure during and after pregnancy, endogenous lead sources from past exposure before immigration continue to influence blood lead levels in this sample.

NT-020, a natural therapeutic approach to optimize spatial memory performance and increase neural progenitor cell proliferation and decrease inflammation in the aged rat

The process of aging is linked to oxidative stress, microglial activation, and proinflammatory factors, which are known to decrease cell proliferation and limit neuroplasticity. These factors may lead the transition from normal aging to more severe cognitive dysfunction associated with neurodegenerative diseases. We have shown that natural compounds such as polyphenols from blueberry and green tea and amino acids like carnosine are high in antioxidant and antiinflammatory activity that decreases the damaging effects of reactive oxygen species (ROS), in the blood, brain, and other tissues of the body. Furthermore, we have shown that the combination of these nutrients (called NT-020) creates a synergistic effect that promotes the proliferation of stem cells in vitro and in vivo. In the current study, we examined the effects of NT-020 on neurogenesis and performance on a Morris water maze (MWM). Aged (20-month-old) male Fischer 344 rats were treated with 135.0 mg/kg per day (n = 13) of NT-020. Young (3-month-old) (n = 10) and aged (20-month-old) (n = 13) control male Fischer 344 rats were treated with water by oral gavage. All groups were treated for a period of 4 weeks. Although there was no difference in performance in the MWM when comparing all aged rats, when the data for aged impaired rats were compared, there was a significant difference between groups on the last day of training with the treatment group performing better than controls. Using the cell cycle-regulating protein (Ki67), doublecortin (DCX), and OX6 antibody markers, cell proliferation, neurogenesis, and microglial activation were estimated in the dentate gyrus (DG) of young and aged animals. Cell proliferation was also examined in the subventricular zone (SVZ). A decreased number of OX6 MHC II-positive cells, increased neurogenesis, and increased number of proliferating cells were found in rats treated with NT-020 in comparison with aged control rats. In sum, NT-020 may promote health, proliferation, and maintenance of neurons in the age animals and exert antiinflammatory actions that promote function in the aged stem cell niche.

Negative-pressure wound therapy for prevention and treatment of surgical-site infections after vascular surgery

BACKGROUND

Indications for negative-pressure wound therapy (NPWT) in vascular surgical patients are expanding. The aim of this review was to outline the evidence for NPWT on open and closed wounds.

METHODS

A PubMed, EMBASE and Cochrane Library search from 2007 to June 2016 was performed combining the medical subject headings terms 'wound infection', 'abdominal aortic aneurysm (AAA)', 'fasciotomy', 'vascular surgery' and 'NPWT' or 'VAC'.

RESULTS

NPWT of open infected groin wounds was associated with shorter duration of wound healing by 47 days, and was more cost-effective than alginate dressings in one RCT. In one RCT and six observational studies, NPWT-related major bleeding and graft preservation rates were 0-10 and 83-100 per cent respectively. One retrospective comparative study showed greater wound size reduction per day, fewer dressing changes, quicker wound closure and shorter hospital stay with NPWT compared with gauze dressings for lower leg fasciotomy. NPWT and mesh-mediated fascial traction after AAA repair and open abdomen was associated with high primary fascial closure rates (96-100 per cent) and low risk of graft infection (0-7 per cent). One retrospective comparative study showed a significant reduction in surgical-site infection, from 30 per cent with standard wound care to 6 per cent with closed incisional NPWT.

CONCLUSION

NPWT has a central role in open and infected wounds after vascular surgery; the results of prophylactic care of closed incisions are promising.

Maternal blood lead level during pregnancy in South Central Los Angeles

Twenty-five years of public health efforts produced a striking reduction in lead exposure; the blood lead average in the United States has decreased to less than 20% of levels measured in the 1970s. However, poor minority groups that live in large urban centers are still at high risk for elevated lead levels. In this study, our data showed that pregnant immigrants (n = 1,428) who live in South Central Los Angeles--one of the most economically depressed regions of California--have significantly higher (p < .0001) blood lead levels (geometric mean = 2.3 microg/dl [0.11 micromol/l]) than 504 pregnant nonimmigrants (geometric mean = 1.9 microg/dl [0.09 micromol/l]). The most important factors associated with lower blood lead levels in both groups were younger age; more-recent date of blood sampling (i.e., decreasing secular trend); and blood sampling in mid-autumn, instead of mid-spring (i.e., seasonal trend). Blood lead levels of immigrants were strongly dependent on time elapsed since immigration to the United States; each natural log increase in years of residence was associated with an approximately 19% decrease in blood lead levels. Although blood lead means for both groups were almost the same as the estimated national average, 25 of the 30 cases of elevated blood lead (i.e., > or = 10 microg/dl [0.48 micromol/l) occurred in the immigrant group. The odds ratio (95% confidence intervals within parentheses) for having elevated blood lead levels (a) was 9.3 (1.9, 45.8) if the immigrant engaged in pica; (b) was 3.8 (1.4, 10.5) if the immigrant had low dietary calcium intake during pregnancy; and (c) was .65 (.43, .98) for every natural log unit increase of years of residence in the United States. The control of pica and dietary calcium intake may offer a means of reducing lead exposure in immigrants.

Outcome and complications after intra-arterial thrombolysis for lower limb ischaemia with or without continuous heparin infusion

Background

Thrombolysis is a common treatment for acute leg ischaemia. The purpose of this study was to evaluate different thrombolytic treatment strategies, and risk factors for complications.

Methods

This was a retrospective analysis of prospective databases from two vascular centres. One centre used a higher dose of heparin and recombinant tissue plasminogen activator (rtPA).

Results

Some 749 procedures in 644 patients of median age 73 years were studied; 353 (47·1 per cent) of the procedures were done in women. The aetiology of ischaemia was graft occlusion in 38·8 per cent, acute arterial thrombosis in 32·2 per cent, embolus in 22·3 per cent and popliteal aneurysm in 6·7 per cent. Concomitant heparin infusion was used in 63·2 per cent. The mean dose of rtPA administered was 21·0 mg, with a mean duration of 25·2 h. Technical success was achieved in 80·2 per cent. Major amputation and death within 30 days occurred in 13·1 and 4·4 per cent respectively. Bleeding complications occurred in 227 treatments (30·3 per cent). Blood transfusion was needed in 104 (13·9 per cent). Three patients (0·4 per cent of procedures) had intracranial bleeding; all were fatal. Amputation-free survival was 83·6 per cent at 30 days at both centres. In multivariable analysis, preoperative severe ischaemia with motor deficit was the only independent risk factor for major bleeding (odds ratio (OR) 2·98; P <0·001). Independent risk factors for fasciotomy were severe ischaemia (OR 2·94) and centre (OR 6·50). Embolic occlusion was protective for major amputation at less than 30 days (OR 0·30; P = 0·003). Independent risk factors for death within 30 days were cerebrovascular disease (OR 3·82) and renal insufficiency (OR 3·86).

Conclusion

Both treatment strategies were successful in achieving revascularization with acceptable complication rates. Continuous heparin infusion during intra-arterial thrombolysis appeared to offer no advantage.

Blood lead level and blood pressure during pregnancy in South Central Los Angeles

In many studies in which the relationship between blood pressure and blood lead level has been examined, investigators have found significant--but small--associations. There was only one previous report of a significant association of blood lead with blood pressure in pregnant women. We measured blood lead level and sitting blood pressure of 1,627 women in their third trimester of pregnancy. We eliminated subjects with known causes of hypertension. Most women (98.4%) were normotensive. We controlled for body mass index, age, and stress--among other factors--and constructed multiple-regression models of lead association with diastolic and systolic blood pressures. Immigrants (73% of total) had significantly higher blood lead levels and different blood pressures than nonimmigrants, suggesting that analysis be stratified by "immigrant, nonimmigrant" status. Positive relationships between blood lead level and blood pressure were found only for immigrants (p < or = .001). From the 5th to 95th blood-lead percentiles (0.9-6.2 microg/dl) in immigrants, systolic blood pressure increased 2.8 mm Hg, and diastolic blood pressure increased 2.4 mm Hg. Higher prior lead exposure of immigrants (97.7% from Latin countries) than nonimmigrants might explain the differential effect of these low levels of blood lead on blood pressure in nonimmigrants. Perhaps some immigrants are at higher risk than nonimmigrants for lead-associated elevated blood pressure during pregnancy, despite blood lead levels within the currently considered acceptable range.

Meta-analysis of negative pressure wound therapy of closed groin incisions in arterial surgery

BACKGROUND

Surgical-site infection (SSI) after groin incisions for arterial surgery is common and may lead to amputation or death. Incisional negative pressure wound therapy (NPWT) dressings have been suggested to reduce SSIs. The aim of this systematic review with meta-analysis was to assess the effects of incisional NPWT on the incidence of SSI in closed groin incisions after arterial surgery.

METHODS

A study protocol for this systematic review of RCTs was published in Prospero (CRD42018090298) a priori, with predefined search, inclusion and exclusion criteria. The records generated by the systematic research were screened for relevance by title and abstract and in full text by two of the authors independently. The selected articles were rated for bias according to the Cochrane risk-of-bias tool.

RESULTS

Among 1567 records generated by the search, seven RCTs were identified, including 1049 incisions. Meta-analysis showed a reduction in SSI with incisional NPWT (odds ratio (OR) 0·35, 95 per cent c.i. 0·24 to 0·50; P < 0·001). The heterogeneity between the included studies was low (I²  = 0 per cent). The quality of evidence was graded as moderate. Two studies had multiple domains in the Cochrane risk-of-bias tool rated as high risk of bias. A subgroup meta-analysis of three studies of lower limb revascularization procedures only (363 incisions) demonstrated a similar reduction in SSI (OR 0·37, 0·22 to 0·63; P < 0·001; I²  = 0 per cent).

CONCLUSION

Incisional NPWT after groin incisions for arterial surgery reduced the incidence of SSI compared with standard wound dressings. The risk of bias highlighted the need for a high-quality RCT with cost-effectiveness analysis.

Mid-term outcome of endovascular revascularization for chronic mesenteric ischaemia

Background

This study aimed to assess mid-term outcome after endovascular revascularization of chronic occlusive mesenteric ischaemia (CMI) and to identify possible predictors of mortality.

Methods

Consecutive patients undergoing primary elective stenting for CMI between 1995 and 2007 were registered prospectively in a database. Patients with acute ischaemia were excluded. Retrospective case-note review and data analysis were performed.

Results

Forty-three patients (10 men) were treated for stable (n = 30) or exacerbated (n = 13) CMI. Their median (interquartile range (i.q.r.)) age was 70 (60–79) years. Revascularization was successful in 47 of 49 vessels. The superior mesenteric artery (SMA), either alone (n = 34) or in combination with the coeliac trunk (n = 6), was the predominant target vessel. No patient died within 30 days. Median follow-up was 43 (i.q.r. 25–63) months and the estimated (s.e.) 3-year overall survival rate was 76(7) per cent. Two patients died from distal SMA occlusive disease and intestinal infarction after 6 and 18 months respectively. Previous stroke (P = 0·016), male sex (P = 0·057) and age (P = 0·066) were associated with mid-term mortality on univariable, but not multivariable analysis. Reintervention was needed in 14 patients, achieving a 3-year cumulative rate of freedom from recurrent symptoms of 88(5) per cent.

Conclusion

Endovascular treatment provided high early and mid-term survival rates in this series of patients with CMI, with low complication rates.

One-year follow-up after open abdomen therapy with vacuum-assisted wound closure and mesh-mediated fascial traction

BACKGROUND

Open abdomen (OA) therapy frequently results in a giant planned ventral hernia. Vacuum-assisted wound closure and mesh-mediated fascial traction (VAWCM) enables delayed primary fascial closure in most patients, even after prolonged OA treatment. Our aim was to study the incidence of hernia and abdominal wall discomfort 1 year after abdominal closure.

METHODS

A prospective multicenter cohort study of 111 patients undergoing OA/VAWCM was performed during 2006-2009. Surviving patients underwent clinical examination, computed tomography (CT), and chart review at 1 year. Incisional and parastomal hernias and abdominal wall symptoms were noted.

RESULTS

The median age for the 70 surviving patients was 68 years, 77 % of whom were male. Indications for OA were visceral pathology (n = 40), vascular pathology (n = 22), or trauma (n = 8). Median length of OA therapy was 14 days. Among 64 survivors who had delayed primary fascial closure, 23 (36 %) had a clinically detectable hernia and another 19 (30 %) had hernias that were detected on CT (n = 18) or at laparotomy (n = 1). Symptomatic hernias were found in 14 (22 %), 7 of them underwent repair. The median hernia widths in symptomatic and asymptomatic patients were 7.3 and 4.8 cm, respectively (p = 0.031) with median areas of 81.0 and 42.9 cm(2), respectively (p = 0.025). Of 31 patients with a stoma, 18 (58 %) had a parastomal hernia. Parastomal hernia (odds ratio 8.9; 95 % confidence interval 1.2-68.8) was the only independent factor associated with an incisional hernia.

CONCLUSIONS

Incisional hernia incidence 1 year after OA therapy with VAWCM was high. Most hernias were small and asymptomatic, unlike the giant planned ventral hernias of the past.

Epidemiology and Long-Term Prognostic Factors in Acute Type B Aortic Dissection

The epidemiological data and reports on long-term predictors of mortality after medically or endovascularly and medically treated patients with acute type B aortic dissection (AD) are scarce. Patients with type B AD between 2000 and 2004 were identified through the inpatient endovascular or autopsy registry at Malmö-Lund University Hospital, Sweden. Seventy-two patients had acute type B AD, of whom eight were found at autopsy. Shock due to ruptured type B AD was associated with in-hospital mortality (P = 0.006) in the 64 eligible patients. Renal insufficiency (odds ratio [OR] = 4.7, 95% confidence interval [CI] 1.1-19.4) and coexistent aortic disease (OR = 4.1, 95% CI 1.0-16.9) remained as independent predictors for long-term mortality after multivariate logistic regression analysis. Endovascular intervention (n = 32) was associated with neither short- nor long-term mortality. The estimated overall incidence of acute type B AD was 2.1/100,000 person-years, and the highest incidence rates were found in men aged 65-74 years (14.6/100,000 person-years) and women aged 75-84 years (19.0/100,000 person-years). Survival in patients with complicated acute type B AD managed with the endovascular technique was the same as in uncomplicated medically treated patients. Renal insufficiency and coexistent aortic disease were strong predictors for long-term mortality.