111 research outputs found
Intraoperative determinants of infrainguinal bypass graft patency: A prospective study
Objectives:To evaluate a number of currently available methods for intraoperative assessment of infrainguinal bypass grafts (IBG) in terms of detecting technical errors and predicting graft failure.Design:Prospective open clinical study.Methods:Forty-nine patients undergoing 54 consecutive IBG were studied. Intraoperatively, the following measurements were performed: distal pulse palpation (DPP), continuous wave Doppler (CWD), pulse volume recording (PVR), and ultrasonic volume flowmetry (UVF), followed by intraoperative angiography of the entire graft and runoff vessels. The outflow resistance was graded according to the guidelines of the Society for Vascular Surgery and International Society for Cardiovascular Surgery (SVS/ISCVS runoff score). Graft patency was determined noninvasively (PVR, colour Duplex) up to 12 months following surgery. Predictive values and likelihood ratios for the intraoperative tests in detecting a technical problem during the bypass procedure and in predicting early graft failure were calculated.Results:There were five immediate revisions for problems detected intraoperatively. Angiography did not identify any additional problems but assisted in the correct location of the problems detected by the other tests. DPP and CWD were highly significant indicators of the need for revision with likelihood ratios for a positive test of 14.7 (p < 0.01) and 12.3 (p < 0.01) respectively. PVR did not achieve statistical significance in this respect. None of the intraoperative tests was a statistically significant predictor of early graft failure. The SVS/ISCVS runoff score, on the other hand, predicted early failure with a PPV of 33% (likelihood ratio for a positive test of 4.9, p < 0.05). None of the grafts with a perfect SVS/ISCVS runoff score (n = 39) failed in the first postoperative month.Conclusions:Simple CWD insonation of graft and anastomoses is the best intraoperative indicator for technical inadequacies after IBG. Routine intraoperative angiography is not necessary and intraoperative anatomical imaging may be reserved for situations in which noninvasive documentation of technical success is absent. Contrary to the intraoperative haemodynamic test results, the SVS/ISCVS runoff score is a good predictor of early graft failure
The Effects of Long-Term Graft Preservation on Intraoperative Hemostatic Changes in Liver Transplantation:A Comparison Between Orthotopic and Heterotopic Transplantation in the Pig
We compared hemostatic changes during OLT and HLT after various periods of graft storage, to investigate whether the host liver in HLT protects the recipient from hemostatic deterioration induced by severe graft storage damage. In particular, the mechanism of fibrinolytic deterioration was investigated. The effect of prostaglandin E1 (PGE1) on these parameters was also studied. Material and Methods: 69 pigs underwent either OLT (N = 32) or HLT (N = 37) with a graft stored for 2 hr (N = 31), 24 hr (N = 16), 48 hr (N = 7), or 72 hr (N = 15). PGE1 was given intravenously to both donor and recipient animals and was added to the preservation and flushing solutions. Fibrinolysis (euglobulin clot lysis time, t-PA activity and α2-antiplasmin) and coagulation parameters (activated partial thromboplasmin time, prothrombin time, fibrinogen and platelet count) were measured at several intervals during transplantation. Statistics: Univariate non-parametric tests were used for analysis of coagulation and fibrinolysis parameters. For the three main variables- i.e., the type of transplantation, the use of PGE1, and the preservation time, multiple regression analysis was performed. Results: Fibrinolytic activity increased during the anhepatic period of OLT. Graft reperfusion was followed by a rise in t-PA in both OLT and HLT. In HLT, t-PA quickly returned to normal, whereas a continuous increase was found in OLT. The coagulation parameters, in turn, remained unchanged during the anhepatic period and deteriorated in OLT compared to HLT. The duration of graft storage was directly related to the severity of the hemostatic changes, although this effect was more apparent in OLT than in HLT. Conclusions: Changes in hemostasis are more pronounced in OLT than in HLT. This suggests that the host liver protects the recipient from the effects of graft storage damage, even after long preservation times. Early postreperfusion fibrinolytic activity was presumably due to t-PA release from the graft both in OLT and HLT. The further rise t-PA in OLT might be caused by the release of cytokines from the graft, that subsequently evoke endothelial t-PA release. In HLT, t-PA and cytokines may be cleared by the native liver. No positive or negative effect of PGE1 on coagulation or fibrinolysis parameters was noticed.\</p
The Effects of Long-Term Graft Preservation on Intraoperative Hemostatic Changes in Liver Transplantation:A Comparison Between Orthotopic and Heterotopic Transplantation in the Pig
We compared hemostatic changes during OLT and HLT after various periods of graft storage, to investigate whether the host liver in HLT protects the recipient from hemostatic deterioration induced by severe graft storage damage. In particular, the mechanism of fibrinolytic deterioration was investigated. The effect of prostaglandin E1 (PGE1) on these parameters was also studied. Material and Methods: 69 pigs underwent either OLT (N = 32) or HLT (N = 37) with a graft stored for 2 hr (N = 31), 24 hr (N = 16), 48 hr (N = 7), or 72 hr (N = 15). PGE1 was given intravenously to both donor and recipient animals and was added to the preservation and flushing solutions. Fibrinolysis (euglobulin clot lysis time, t-PA activity and α2-antiplasmin) and coagulation parameters (activated partial thromboplasmin time, prothrombin time, fibrinogen and platelet count) were measured at several intervals during transplantation. Statistics: Univariate non-parametric tests were used for analysis of coagulation and fibrinolysis parameters. For the three main variables- i.e., the type of transplantation, the use of PGE1, and the preservation time, multiple regression analysis was performed. Results: Fibrinolytic activity increased during the anhepatic period of OLT. Graft reperfusion was followed by a rise in t-PA in both OLT and HLT. In HLT, t-PA quickly returned to normal, whereas a continuous increase was found in OLT. The coagulation parameters, in turn, remained unchanged during the anhepatic period and deteriorated in OLT compared to HLT. The duration of graft storage was directly related to the severity of the hemostatic changes, although this effect was more apparent in OLT than in HLT. Conclusions: Changes in hemostasis are more pronounced in OLT than in HLT. This suggests that the host liver protects the recipient from the effects of graft storage damage, even after long preservation times. Early postreperfusion fibrinolytic activity was presumably due to t-PA release from the graft both in OLT and HLT. The further rise t-PA in OLT might be caused by the release of cytokines from the graft, that subsequently evoke endothelial t-PA release. In HLT, t-PA and cytokines may be cleared by the native liver. No positive or negative effect of PGE1 on coagulation or fibrinolysis parameters was noticed.\</p
The Effects of Long-Term Graft Preservation on Intraoperative Hemostatic Changes in Liver Transplantation
We compared hemostatic changes during OLT and HLT after various periods of graft storage, to
investigate whether the host liver in HLT protects the recipient from hemostatic deterioration induced
by severe graft storage damage. In particular, the mechanism of fibrinolytic deterioration was
investigated. The effect of prostaglandin E1 (PGE1) on these parameters was also studied
Results from a nationwide prospective registry on open surgical or endovascular repair of juxtarenal abdominal aortic aneurysms
Background: Juxtarenal abdominal aortic aneurysms (JRAAAs) can be treated either with open surgical repair (OSR) including suprarenal clamping or by complex endovascular aneurysm repair (cEVAR). In this study, we present the comparison between the short-term mortality and complications of the elective JRAAA treatment modalities from a national database reflecting daily practice in the Netherlands. Methods: All patients undergoing elective JRAAA open repair or cEVAR (fenestrated EVAR or chimney EVAR) between January 2016 and December 2018 registered in the Dutch Surgical Aneurysm Audit (DSAA) were eligible for inclusion. Descriptive perioperative variables and outcomes were compared between patients treated with open surgery or endovascularly. Adjusted odds ratios for short-term outcomes were calculated by logistic regression analysis. Results: In all, 455 primary treated patients with JRAAAs could be included (258 OSR, 197 cEVAR). Younger patients and female patients were treated more often with OSR vs cEVAR (72 ± 6.1 vs 76 ± 6.0; P < .001 and 22% vs 15%; P = .047, respectively). Patients treated with OSR had significantly more major and minor complications as well as a higher chance of early mortality (OSR vs cEVAR, 45% vs 21%; P < .001; 34% vs 23%; P = .011; and 6.6% vs 2.5%; P = .046, respectively). After logistic regression with adjustment for confounders, patients who were treated with OSR showed an odds ratio of 3.64 (95% confidence interval [CI], 2.25-5.89; P < .001) for major complications compared with patients treated with cEVAR, and for minor complications, the odds ratios were 2.17 (95% CI, 1.34-3.53; P = .002) higher. For early mortality, the odds ratios were 3.79 (95% CI, 1.26-11.34; P = .017) higher after OSR compared with cEVAR. Conclusions: In this study, after primary elective OSR for JRAAA, the odds for major complications, minor complications, and short-term mortality were significantly higher compared with cEVAR
Genomic DNA Pooling Strategy for Next-Generation Sequencing-Based Rare Variant Discovery in Abdominal Aortic Aneurysm Regions of Interest—Challenges and Limitations
The costs and efforts for sample preparation of hundreds of individuals, their genomic enrichment for regions of interest, and sufficient deep sequencing bring a significant burden to next-generation sequencing-based experiments. We investigated whether pooling of samples at the level of genomic DNA would be a more versatile strategy for lowering the costs and efforts for common disease-associated rare variant detection in candidate genes or associated loci in a substantial patient cohort. We performed a pilot experiment using five pools of 20 abdominal aortic aneurysm (AAA) patients that were enriched on separate microarrays for the reported 9p21.3 associated locus and 42 additional AAA candidate genes, and sequenced on the SOLiD platform. Here, we discuss challenges and limitations connected to this approach and show that the high number of novel variants detected per pool and allele frequency deviations to the usually highly false positive cut-off region for variant detection in non-pooled samples can be limiting factors for successful variant prioritization and confirmation. We conclude that barcode indexing of individual samples before pooling followed by a multiplexed enrichment strategy should be preferred for detection of rare genetic variants in larger sample sets rather than a genomic DNA pooling strategy
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