Postoperative Blood Samples Research Articles

Effects of Cardiac Surgery and Salvaged Blood Transfusion on Coagulation Function Assessed by Thromboelastometry

Coagulation function dynamically changes during cardiac surgery and is normalized after surgery. The authors investigated changes of coagulation function during cardiac surgery and after mimicked salvaged blood transfusion (SBT), and determined background risk factors for coagulation dysfunction by thromboelastmetry including maximum clot firmness of fibrinogen assay (FIBTEM-MCF: primary variable). Prospective observational study with ex vivo laboratory experiment. University hospital. Consecutive 65 adult elective cardiac surgery patients being scheduled to use cell salvage technique. Arterial blood sampling (preoperative: after anesthesia induction, and postoperative: after reversal of heparin), and ex vivo dilution of postoperative blood with salvaged blood (7.4%: 2.5 mL + 0.2 mL and 18.5%: 2.2 mL + 0.5 mL). Thromboelastometry was performed for the preoperative blood sample, and postoperative blood samples mixed with different amount of the salvaged blood. Preoperative FIBTEM-MCF significantly decreased after cardiac surgery (16.5 [95% confidence interval (15.4-17.6)] mm to 9.5 [8.4-10.6] mm, p < 0.0001). In vitro 7.4% and 18.5% salvaged blood addition dose-dependently reduced FIBTEM-MCF (9.1 [95% confidence interval (8.0-10.1)] mm, 7.9 [6.8-9.0] mm, respectively, p < 0.0001). Preoperative FIBTEM-MCF and changes of FIBTEM-MCF during cardiac surgery were independent risk factors for development of the FIBTEM-MCF 8 mm or less after in vitro salvaged blood addition. Furthermore, residual heparin within salvaged blood was indicated by significant increase of intrinsic assay-clotting time/ heparin assay-clotting time after 18.5% in vitro salvaged blood addition (p < 0.0001). Salvaged blood transfusion of more than 18.5% whole blood volume may impair coagulation function particularly in patients with lower FIBTEM-MCF before and after cardiac surgery.

D-dimer Düzeyi Koroner Arter Baypas Cerrahisinden Sonra İskemi/Reperfüzyon Hasarının Bir Bulgusudur

Introduction: Myocardial Ischaemia-Reperfusion (I-R) injury produces a spectrum of clinical cardiovascular outcomes after cardiac surgery. The pathogenesis of I-R injury is complex and involves the activation and amplification of several systemic and local proinflammatory pathways. The process of restoring blood flow to the ischaemic myocardium can induce injury and paradoxically reduce the beneficial effects of myocardial reperfusion. The objective of this study was to determine the correlation between cardiac markers such as the Mb fraction of the creatine kinase (CK-MB), troponin I (cTnI) and D-dimer levels as a marker of myocardial injury secondary to I-R injury after coronary artery bypass surgery. Patients and Methods: Herein, a prospective study was designed that included 50 consecutive coronary artery bypass grafting (CABG) patients. Pre and postoperative blood samples were taken due to study protocol and such markers as Mb fraction of the creatine kinase (CK-MB), troponin I (cTnI) and D-dimer were measured. Results: All three markers were significantly elevated in postoperative blood samples. The D-dimer level reached its peak at the first and another peak at 12th hour postoperatively. However, the peak serum values of CK-MB and cTnI occurred at 6th and 12th hour, respectively. Conclusion: We demonstrated that D-dimer levels as a marker of generated thrombin during reperfusion correlated with other well-known biochemical markers of myocardial damage in the postoperative period. In other words, D-dimer levels may stand as a marker of I-R-induced myocardial damage.

Nursing and training of pigs used in renal transplantation studies.

The pig is commonly used in renal transplantation studies since the porcine kidney resembles the human kidney. To meet the requirements of intense caretaking and examination without stress, a 2-week socialisation and training programme was developed. Conventional cross-breed pigs (n = 36) with high health status were trained for 15 min/day in a four-step training programme before kidney transplantation. The systematic training resulted in calm animals, which allowed for ultrasound examination, blood sampling and urine sampling without restraint. When a 2-methacryloyloxyethyl phosphorylcholine polymer-coated jugular catheter introduced via the auricular vein was used for post-operative blood sampling, clotting was avoided. To assess renal function, urinary output was observed and creatinine and cystatin C were measured; the latter was not found to be useful in recently transplanted pigs. The results presented contribute to the 3Rs (refine, reduce, replace).

Downregulation of serum exosomal miR-150-5p is associated with poor prognosis in patients with colorectal cancer.

Growing evidence have revealed the serum exosomal miRNAs emerged as biomarkers for various cancer types, including colorectal cancer (CRC). Here, we sought to explore the potential clinical significance of serum exosomal miR-150-5p in CRC. A total of 133 CRC patients and 60 healthy volunteers as control group were recruited in this study. Exosomes were isolated from the serum of all the participants. The total RNA was isolated from the exosomes and the serum exosomal miR-150-5p levels were measured by quantitative reverse transcription-polymerase chain reaction. The findings showed that the serum exosomal miR-150-5p levels were significantly reduced in CRC cases compared with those in the control group. Serum exosomal miR-150-5p levels in post-operative blood samples were greatly upregulated one month after surgical treatment. In addition, decreased serum exosomal miR-150-5p expression was closely correlated with poorly differentiation, positive lymph node metastasis and advanced TNM stage. Moreover, receiver operating characteristic (ROC) curve analysis showed serum exosomal miR-150-5p level had good performance to identify CRC cases from healthy volunteers, and a combination of serum exosomal miR-150-5p and carcinoembryonic antigen (CEA) could improve the diagnostic accuracy with an increased the area under the ROC curve (AUC) value. Furthermore, the survival time of patients with higher serum exosomal miR-150-5p expression was significantly longer than those with lower expression. Serum exosomal miR-150-5p was confirmed as an independent prognostic indicator in CRC. Mechanistically, ZEB1 was identified as a direct downstream target of miR-150-5p. Collectively, serum exosomal miR-150-5p might be a novel noninvasive biomarker for CRC diagnosis and prognosis.

Clinical response and prognostic significance of serum miR-497 expression in colorectal cancer.

Colorectal cancer (CRC) is a common type of cancer around the world. Detection of microRNA (miRNA) aberration in blood samples is a novel approach for CRC screening. The purpose of this study was to explore the serum miR-497 expression pattern in CRC and examine its potential usefulness as a biomarker for CRC diagnosis and prognosis. Serum miR-497 expression was evaluated by quantitative reverse transcription polymerase chain reaction (qRT-PCR) in 110 patients with CRC, 35 cases with colorectal adenoma, 54 cases with colorectal polyps, and 70 healthy individuals. The expression level of miR-497 was significantly downregulated in CRC tissues compared to the normal tissues based on the data from three independent studies GSE68204, GSE41655 and GSE35834. Compared to healthy controls, the serum miR-497 level was significantly decreased in patient with CRC or benign lesion (colorectal adenoma and polyps). Serum miR-497 level was dramatically increased in the post-operative blood samples from early stage CRC patients. Receiver-operating characteristic (ROC) analysis showed that serum miR-497 had a high sensitivity and specificity for discriminating CRC or precancerous colorectal lesion from normal controls. Moreover, low serum miR-497 expression was closely correlated with aggressive clinical features and shorter overall survival (OS). Kaplan-Meier analyses also revealed that OS was strongly associated with lymph node invasion, TNM stage and histological grade. Furthermore, univariate and multivariate analysis showed serum miR-497 was an independent prognostic factor for CRC. Collectively, serum miR-497 may serve as a promising biomarker for diagnosis and prognosis of CRC.

Galanin expression is down-regulated in patients with gastric cancer.

ObjectiveTo investigate whether galanin and its three receptors (Gal-R1, Gal-R2, Gal-R3) contribute to development of gastric cancer.MethodsPreoperative and postoperative fasting venous blood samples were collected from 34 patients with gastric cancer and 13 healthy individuals. Plasma galanin contents, as well as expression levels of galanin and its receptors, were quantitatively examined in a cohort of human gastric cancer tissues and corresponding adjacent tissues.ResultsStatistically significantly lower galanin levels were found in the preoperative samples from patients with gastric cancer, compared with postoperative samples from these same patients, as well as with samples from healthy donors. Furthermore, galanin and Gal-R1 expression levels were dramatically reduced in gastric cancer tissues, compared with corresponding adjacent tissues, whereas Gal-R2 and Gal-R3 levels remained unchanged. Furthermore, galanin mRNA and protein expression levels in the preoperative samples from patients with gastric cancer were significantly correlated with lymph node metastasis, tumor node metastasis stage, and size of the gastric cancer.ConclusionsOverall levels of galanin and Gal-R1 expression were down-regulated in patients with gastric cancer; local levels were also specifically downregulated in gastric cancer tissues. Galanin and its receptor, Gal-R1, may contribute to development of gastric cancer.

The early- and mid-term results of our endovascular aneurysm repairs in thoracic aortic pathologies

Aim: Endovascular therapy can be an alternative option to open surgical treatment in high-risk patients with dissecting or pure aneurysmal dilation of aorta. Endovascular therapy is associated with less complication rates, as well as shorter hospital stay and favourable blood products need perioperatively when compared to those in open surgical treatment. Our study aims to present a single center experience by evaluating the early and midterm follow-up results of thoracic endovascular aortic repairs (TEVAR). Material and Methods: Nineteen patients who underwent TEVAR procedure between March 2005 and March 2011 were evaluated retrospectively. Pre- and postoperative blood samples and computerized tomography angiograpy (CTA) results were compared. The type of stent graft used, need for blood product, postprocedural complications were evaluated.Results: The patients’ mean length of hospital stay was 12,8±6.5 days. The mean age was 56.1±8.7 years. Two patients (10.5%) were urgently taken to operation; one of these (5.2%) was exitus on the postoperative day 7. None of the patients developed thromboembolic or neurological complication. Three patients (15.7%) developed endoleaks in their early-term follow-up whereas none had endoleaks in their mid-term follow-up. There was a statistically significant difference between the preoperative and postoperative hemoglobin and hematocrit values of the patients (p0.05). Conclusion: Endovascular aneurysm repair in thoracic aortic pathologies can be an alternative to surgery in suitable cases. However, we are of the opinion that the experience of surgical team to perform this procedure with this subject will be useful in reducing the complication rates. Keywords: Thoracic; aorta; endovascular; TEVAR.

Spillage of bacterial products during colon surgery increases the risk of liver metastases development in a rat colon carcinoma model.

ABSTRACTSurgical resection of the primary tumor provides the best chance of cure for patients with colorectal carcinoma (CRC). However, bacterial translocation during intestinal surgery has been correlated with poor long-term oncological outcome. Therefore, we investigated the influence of bacterial contamination during colon surgery on CRC liver metastases development. Blood and liver samples of patients undergoing resection of primary CRC or liver metastases were collected. Cell numbers, activation markers and inflammatory mediators were determined. Tumor cell adhesion and outgrowth after sham- or colectomy operations were determined in a rat model, in which tumor cells had been injected into the portal vein.White blood cells and granulocytes were increased in per- and post-operative patient blood samples. IL-6 was also increased post-operatively compared to the preoperative level. Expression of NOX-2, NOX-4 and polymorphonuclear cells (PMNs) numbers were elevated in post-operative human liver samples. In vitro stimulation of macrophages with plasma of rats after colectomy resulted in production of reactive oxygen species (ROS). Colectomy in rats increased D-lactate levels in plasma, supporting bacterial translocation. Decreased expression of tight junction molecules and increased tumor cell adhesion and outgrowth was observed. Treatment with a selective decontamination of the digestive tract (SDD) cocktail decreased tumor cell adherence after colectomy.In conclusion, postoperative bacterial translocation may activate liver macrophages and PMNs, resulting in ROS production. As we previously showed that ROS release led to liver vasculature damage, circulating tumor cells may adhere to exposed extracellular matrix and grow out into liver metastases. This knowledge is pivotal for development of therapeutic strategies to prevent surgery-induced liver metastases development.

The Clearance of Serum Human Epididymis Protein 4 Following Primary Cytoreductive Surgery for Ovarian Carcinoma.

The aim of this study was to examine the clearance of serum human epididymis protein 4 (HE4) in the immediate postoperative period in patients undergoing maximal effort cytoreductive surgery for ovarian carcinoma. The study was performed at a tertiary gynecologic oncology center. The surgery was performed by accredited gynecological oncologists. Preoperative and serial postoperative venous blood samples at 4, 8, 24, 48, 72, 96, and 120 hours were taken from 10 sequential patients. Pretreatment HE4 is considered elevated at greater than 70 pmol/L. Human epididymis protein 4 was greater than 70 pmol/L in 7 patients, including all patients with high-grade serous carcinoma. Patients with preoperative elevation of serum HE4 and complete cytoreduction cleared more than 80% of serum HE4 in the first 4 hours and more than 88% within 5 days of surgery. One patient with incomplete cytoreduction of high-grade serous carcinoma had 66% clearance at 4 hours and a plateau thereafter. Human epididymis protein 4 derived from ovarian carcinoma had a short half-life of less than 4 hours in the circulation when cytoreductive surgery was complete. Sustained low HE4 following surgery could be a useful indicator of the completeness of cytoreduction. Plateau or rise in serum HE4 could suggest persistent disease. Comparison of values on day 1 and day 4 or 5 might have value in assessing the completeness of cytoreduction.

Upregulation of serum miR-103 predicts unfavorable prognosis in patients with colorectal cancer.

Circulating microRNAs (miRNAs) have been reported as biomarkers for the early detection of colorectal cancer (CRC). We aimed at evaluating the diagnostic and prognostic value of serum miR-103 in CRC patients. Quantitative reverse-transcription PCR (qRT-PCR) was applied to measure the miR-103 levels in blood samples of 96 patients and 60 controls. Our results demonstrated that serum miR-103 was overexpressed in CRC subjects and the receiver operating characteristic (ROC) curve analysis showed that serum miR-103 could differentiate CRC cases from controls with relatively high accuracy. In addition, serum miR-103 level was more frequently detected in CRC patients with positive lymph node metastasis, distant metastasis and advanced tumor stage. Moreover, serum miR-103 levels in 23 postoperative blood samples were lower than paired preoperative plasma specimens, and serum miR-103 levels were re-elevated in seven patients at recurrence. Furthermore, serum miR-103 was significantly correlated with worse clinical factors, as well as poorer recurrence-free survival or overall survival. Finally, multivariate analysis confirmed that serum miR-103 was an independent prognostic marker for CRC. Taken together, serum miR-103 might be a promising biomarker for diagnosis and prognosis of CRC.

Evaluation of Blood Titanium Levels and Total Bone Contact Area of Dental Implants

The purpose of this study was to evaluate the effect of total implant-bone surface contact area of dental implants applied on partial or total edentulous patients on the increase in the level of blood titanium level. Changes of the blood titanium levels were evaluated after placement of the dental implants in 30 patients including 15 females and 15 males. Patients were divided into 3 groups as dental implants were applied on only maxilla, only mandible, or both of them. Taking into the consideration anatomic formation and prosthetic indication, dental implant-bone total contact area was calculated and saved for each patient after dental implants placement. Blood samples of the patients taken preoperatively and postoperatively at 12 weeks were analyzed by ICP-MS device. Blood titanium levels of preoperative and postoperative blood samples were analyzed for each patient and results were evaluated statistically. In the evaluation after analyzing blood titanium level changes, while a statistically significant decrease was observed in Group 1 patients, a statistically significant increase was observed in Group 2 and Group 3 patients to blood titanium level. A statistically significant difference was observed between Group 1 and Group 2 and between Group 1 and Group 3 patients of blood titanium levels. The change of the blood titanium level was not related to total implant-bone surface area, number of the implants, and gender. In our study, no correlation was found between change of blood titanium level and total contact area with bone of dental implants. We believe that more accurate results can be obtained with biopsy of tissues and organs on animal studies.

Patient-Specific Instrumentation Affects Perioperative Blood Loss in Total Knee Arthroplasty.

Patient-specific instrumentation (PSI) may contribute to reduced blood loss related to total knee arthroplasty (TKA). The purpose of this study was to compare the estimated hemoglobin (Hb) and red blood cell volume (RBC) losses in two groups of patients undergoing TKA with PSI and conventional instrumentation. Pre- and postoperative blood samples were collected from 22 patients randomly assigned to receive a PSI-assisted or conventional TKA. Post- to preoperative Hb difference was calculated and RBC loss was estimated according to Sehat et al. A significant difference in Hb reduction in favor of the PSI group was registered on the last day of stay (p = 0.0084) and significant treatment effect (p = 0.027) on Hb reduction after intervention was found with a regression model for longitudinal measurements. This study demonstrated that PSI leads to a significant trend in earlier Hb regain. These promising results suggest a beneficial effect of PSI in blood loss reduction.

The Use of Point of Care Testing for Monitoring of APTT in Patients Receiving Heparin Infusion

Background: There is a high risk of thromboembolic events among patients undergoing cardiac surgery, and perioperative anticoagulation is sometimes required. The time taken for laboratory based APTT blood sampling results and adjustments may compromise patient safety. There is evidence in the literature to suggest that bedside testing turnaround times is of benefit to inpatient care, and conversely that POCT is inaccurate. The primary aim of this study was to determine if point of care testing of APTT was accurate when compared to laboratory based APTT measurements. The secondary aim was to identify if there was a correlation between operator experience and accuracy of results. Methods: Following full ethics approval by the Royal Adelaide Hospital, Human Research Ethics Committee (HREC), current Cardiothoracic Surgery Unit inpatients were enrolled in the study over a period from July 2016-March 2017. A total of 50 samples were obtained from the minimum number of patients required and separated into three tiers; point of care testing group from finger prick test, point of care testing group from standard postoperative blood sample, and laboratory based testing of standard postoperative blood sample. Results were correlated with Central Adelaide Local Health Network (CALHN) heparin infusion protocols. Clinically significant samples were those which POCT IV and laboratory IV results varied enough to alter the heparin infusion protocol rate change. Results: Demographics showed 83% of patients were male, 67% were receiving IV heparin preoperatively for unstable coronary artery disease, and the mean age of participants was 66 years. Of the 50 collected samples, 17/50 (34%) were recorded as being clinically significant. On the adjusted POCT protocol, 14/50 (28%) of samples were clinically significant. There was a statistically significant difference between POCT IV and laboratory IV results; p = 0.02 and mean difference between values was 19.1. Linear regression analysis showed a poor correlation between POCT IV and laboratory IV samples. There was no relationship between preoperative and postoperative samples. Conclusions: Point of care testing in our study of 50 patient samples shows that there is a poor correlation between POCT and laboratory based testing. Additionally, there is a steep learning curve for those performing the test with no marked improvement following progressive samples. Accordingly, POCT testing in cardiac surgery patients is not recommended for clinical use until further research is completed showing improved correlation between tests, and methods to overcome the steep learning curve are identified.

Tumor-derived exosomal lnc-Sox2ot promotes EMT and stemness by acting as a ceRNA in pancreatic ductal adenocarcinoma.

Long noncoding RNAs (lncRNAs) or exosomes have recently been shown to play vital regulatory or communication roles in cancer biology. However, the roles and mechanisms of exosomal lncRNAs in tumor invasion or metastasis of pancreatic ductal adenocarcinoma (PDAC) remain unknown. In this study, we aimed to investigate the detailed roles and mechanisms of tumor-generated exosomes in progression and metastasis of PDAC in vitro and in vivo. We identified a lncRNA-Sox2ot from exosomes of highly invasive PDAC cells, and analyzed the expression of Sox2ot in the plasma samples and found that the plasma exosomal Sox2ot expression was high and correlated with TNM stage and overall survival rate of PDAC patients. Further research showed that Sox2ot promotes epithelial-mesenchymal transition (EMT) and stem cell like properties by regulating Sox2 expression. Sox2ot competitively binds to the miR-200 family to regulate the expression of Sox2, thus promoting invasion and metastasis of PDAC. We also confirmed the transmission of the exosomes from producer cells to recipient PDAC cells, exosomal Sox2ot can promote tumor invasion and metastasis in vitro and in vivo. We further confirmed tumor generated exosomes could excrete to tumor cell or blood circulation in vivo condition. Finally, we observed a decreased exosomal Sox2ot expression in postoperative blood samples of PDAC patients. The exosomal lncRNA Sox2ot plays important roles in tumor progression and may be a useful maker for pancreatic cancer prognosis.

The predictive value of NT-proBNP and hs-TnT for risk of death in cardiac surgical patients

BackgroundEuropean System for Cardiac Operative Risk Evaluation II (EuroSCORE II) is used for risk stratification before cardiac surgery, but whether N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity troponin T (hs-TnT) may add prognostic information to EuroSCORE II is not known. MethodsPreoperative (n=640) and postoperative (n=629) blood samples were available from cardiac surgical patients with 961-day follow-up (FINNAKI Heart study; cohort #1). The accuracy of a parsimonious risk model with NT-proBNP measurements was also tested in 90 patients with respiratory failure after cardiac surgery (FINNALI study; cohort #2). ResultsSixty-one patients (9.5%) died during follow-up in cohort #1. Preoperative NT-proBNP and hs-TnT concentrations correlated (rho=0.58; p<0.001) and were higher in non-survivors compared to survivors: median 2027 (Q1-3 478-5387) vs. 373 (134–1354) ng/L [NT-proBNP] and 39 (16–191) vs. 13 (8–32) ng/L [hs-TnT]; p<0.001 for both. Preoperative NT-proBNP concentrations were associated with time to death after adjustment for EuroSCORE II (HR [lnNT-proBNP] 1.33 [95% CI 1.08–1.64]), p=0.008 and reclassified patients on top of EuroSCORE II (net reclassification index 0.39 [95% CI 0.14–0.64], p=0.003). Pre- and postoperative NT-proBNP concentrations were closely correlated (rho=0.80, p<0.001) and postoperative NT-proBNP concentrations were also associated with long-term mortality after adjustment for EuroSCORE II. A parsimonious risk model that included age, creatinine clearance, chronic pulmonary disease, and NT-proBNP measurements provided comparable prognostic accuracy as EuroSCORE II in cohort #1 and #2 for risk of long-term mortality. hs-TnT measurements did not add to NT-proBNP measurements ConclusionNT-proBNP measurements could improve and simplify risk prediction in cardiac surgical patients.

Prolonged neuromuscular blockade in a middle-eastern female patient homozygous for atypical plasma cholinesterase.

Sir, Pseudocholinesterase (PchE, also known as “butyrylcholinesterase”) is a serine enzyme capable to hydrolyze choline esters found in succinylcholine, mivacurium, and ester local anesthetics.[1] There are several genetic variants of PchE deficiency. The most important variants are the atypical or dibucaine-resistant, the fluoride-resistant, the silent variant, and the K-variant.[2] The neuromuscular prolongation after succinylcholine in patients with heterozygous or homozygous atypical PchE is variable. Several confounding factors may play a significant role in this prolongation of effect, such as male gender, concomitant use of metoclopramide or etomidate, liver disease, and pregnancy – this latter has been found to decrease PchE activity as early as the 10th week of gestation.[3] The authors present the case of a middle-eastern patient undergoing dilation and curettage who developed prolonged muscle paralysis after single administration of succinylcholine and required postoperative mechanical ventilation. She had no documented allergies and denied prior surgeries. Given that the patient was not appropriately fasted, and due to the emergent nature of the procedure, the decision was to proceed with rapid sequence induction and intubation with propofol, fentanyl, and succinylcholine (1 mg/kg) to facilitate endotracheal intubation, which was uneventful. No further neuromuscular blocker was administered. Ten minutes after the procedure finalized (approximately 45 min after induction), the patient had a persistent neuromuscular blockade, evidenced by train-of-four of 0 and the absence of spontaneous respirations. The decision was made to deepen the anesthesia with intravenous propofol and midazolam and to take the patient sedated and intubated to the postanesthesia care unit. The patient was extubated approximately 4 h after induction in the postanesthesia care unit, after the patient showed adequate muscle strength (head lift >10 s), following verbal commands and tidal volume >5 cc/kg (375 cc/breath) with minimal pressure support from the ventilator. The patient was discharged home on the postoperative day one; on further questioning, she had no recall about the episode. Dibucaine inhibition test was performed using preoperative and postoperative blood samples with results of 20% and 19%, respectively (reference range >80%). This case highlights the importance that besides genetic factors, ethnicity also plays a significant role in the development of this clinical condition, especially in the patient described in our case. Hosseini et al. studied the differences in PchE activity between the Irish population and the Iranian population which corroborated the findings from Szeinberg et al. The differences were based on the dibucaine inhibition test and fluoride test. They concluded that the Iranian population has intrinsically lower levels of PchE activity compared with the Irish population (this latter has higher dibucaine and fluoride numbers). In addition, no difference was observed regarding PchE activity between Iranian Jewish and Muslims.[45] We emphasize the significance of providing the most appropriate management to prevent detrimental outcomes for these patients (e.g., the use of neuromuscular monitoring, mechanical ventilation to avoid respiratory distress, and sedation to avoid awareness) as well as provide adequate education and communication of the diagnosis of PchE deficiency to the patient, family and the medical team in order to prevent exposure to succinylcholine in the future surgical procedures. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.

Postoperative course and prognostic value of circulating angiogenic cytokines after pancreatic cancer resection.

BackgroundCirculating angiogenic cytokines (CACs) have been confirmed as prognostic biomarkers and therapeutic targets in several solid tumors. However, their role as prognostic biomarkers in resected pancreatic ductal adenocarcinoma (PDAC) is unknown.ResultsThe expression of CACs in patients with PDAC differs from those with CP both pre- and postoperatively. Correlation analyses show significant correlations between circulating levels of CACs: VEGF was correlated with IL-6 (r = 0.457), FGF (r = 0.44), G-CSF (r = 0.543), HGF (r = 0.586) and SDF-1α (r = 0.784) before the surgery. The circulating levels of TNF-α correlated with the serum concentration of IL-4 before (r= 0.656) and after the resection (r = 0.776 on POD 3, r = 0.865 on POD 7). Gender did not show any correlation with serum levels of CAC, except for significantly higher levels of EGF in males (P = 0.002). Other clinicopathological variables such as age (< 65 vs. > 65 years), T, N, or UICC stage did not have an association with the cytokine levels. The multivariate model including the entire angiogenic panel revealed that postoperative increasing levels of EGF (P = 0.023), PDGFA-A (P = 0.024), TNF-α (P = 0.001) and IL-8 (P = 0.049) were associated with a favorable prognosis, whereas elevating levels of VEGF (P = 0.005) correlated with a poor cancer-specific survival.Materials and MethodsPreoperative and postoperative blood samples were collected in patients undergoing surgery for PDAC (n = 40) or chronic pancreatitis (CP; n = 9). Serum levels of 13 angiogenic cytokines (IL-4, IL-6, FGF-b, G-CSF, TNF-α, VEGF, HGF, SDF-1α, IL-8, EGF, Ang-1, PDGF-AA and PlGF) were analyzed using ELISA and Multiplex. Prognostic factors were identified by a Cox proportional hazards model.ConclusionsPostoperative changes of serum levels of certain angiogenic cytokines correlate with patients’ prognosis after resection for pancreatic cancer. CACs should thus be considered as biomarkers in patients with resected pancreatic cancer.

Impact of groin flap ischemia-reperfusion on red blood cell micro-rheological parameters in a follow-up study on rats.

Flap hypoperfusion or ischemia-reperfusion (I/R) may occur during preparation-transposition procedures and by postoperative thrombotic complications. Behind the microcirculatory disturbances micro-rheological alterations are also supposed. We aimed to investigate the groin flap I/R with following-up micro-rheological parameters. Anesthetized rats were subjected to Control or I/R groups. Groin flaps were prepared bilaterally, pedicled on the superficial epigastric vessels. In the Control group the flaps were re-sutured after one hour, while in I/R group microvascular clips were applied on the pedicles for 60 minutes, then the flaps were repositioned. Besides daily wound control, before the operation and on the 1st, 3rd, 5th, 7th and 14th postoperative days blood samples were collected for testing red blood cell (RBC) deformability (rotational ektacytometry) and aggregation (light-transmission aggregometry). RBC deformability significantly worsened by the 3rd-7th postoperative day in I/R group. RBC aggregation enhanced significantly by the 1st day, in I/R group it remained elevated on the 3rd day as well. In a complicated case with unilateral flap necrosis, RBC deformability and aggregation worsening was outlined from its group (base, 1st, 3rd day). Wound healing affected micro-rheological parameters in the early postoperative period. Flap I/R exacerbated the alterations. The parameters markedly worsened in case of flap necrosis.

Circulating tumor DNA analysis before and after resection for colorectal cancer.

3597 Background: Detection of circulating tumor DNA (ctDNA) has broad clinical utility including disease monitoring, prognostication and response to chemotherapy. ctDNA is commonly detected by targeting tumor-specific features including mutations, insertions, deletions or hypermethylation. The two genes, BCAT1 and IKZF1, are methylated with high frequency in colorectal cancer (CRC). This study aimed to analyze the impact of tumor resection on ctDNA levels by assaying pre- and postoperative blood samples for methylated BCAT1 and IKZF1. Methods: 91 people (age 32-86 years, 53% male) with invasive CRC, but without neoadjuvant therapy, had blood collected prior to surgery and within 12 months (1-12 months) after resection. Cancers were clinicopathologically staged. DNA extracted from plasma was assayed for methylated BCAT1/ IKZF1 and detection of either marker was deemed positive for ctDNA. Results: 47 (52%) of the 91 CRC patients were ctDNA positive before resection, including 5/30 (17%) stage I, 17/28 (61%) stage II, 23/31 (74%) stage III and 2/2 (100%) stage IV. After resection 75% (35/47) became ctDNA negative (median 2 months after resection), and all had apparent tumour clearance. Of the 35 postoperative ctDNA negative cases 22 had further surveillance CT scans within study timeframe. 86% (20/22) showed no recurrent CRC but 2 of these developed a new cancer (metachronous CRC, prostate). The remaining 2 tested ctDNA positive 14 and 25 months later and recurrence was confirmed. Of the 12 postoperative ctDNA positive cases, two were found to not have complete tumour clearance at surgery (residual disease). Follow-up CT scans were available for a further 8 patients which revealed that 4 later presented with cancer (3 recurrence, 1 thyroid) at a median 15 months after resection. The remaining 4 postoperative positive cases were negative at subsequent blood testing (median 8 months later). Conclusions: Methylated BCAT1/IKZF1 DNA in preoperative blood is dependent on tumor stage, but informs the completeness of resection given the high rate (74.5%) of ctDNA disappearance post-surgery. If cases persistently test ctDNA positive after surgery or become ctDNA positive later, residual or recurrent disease should be suspected, respectively.

Early prediction of clinical outcomes in resected stage II and III colorectal cancer (CRC) through deep sequencing of circulating tumor DNA (ctDNA).

3591 Background: Adjuvant chemotherapy is offered to most pts with Stage III CRC, and to a subset with Stage II disease deemed at high-risk for recurrence. Nevertheless, risk stratification strategies remain suboptimal. Detection of minimal residual disease (MRD) through ctDNA analysis has been shown to identify pts at high recurrence risk in Stage II CRC, but not Stage III disease. Methods: The next-generation sequencing based AVENIO ctDNA Surveillance Kit (Research Use Only) was used to identify single nucleotide variants (SNVs) in tumor tissue within a cohort of 145 Stage II and III CRC pts following R0 surgical resection (n = 86 and 59 respectively; median follow-up = 32.1 mo). The same assay was used to monitor ctDNA with a single post-operative blood sample (mean surgery-to-phlebotomy time: 10 days). Regions from 197 genes recurrently mutated in CRC were interrogated, and pts were classified as ctDNA positive (+) or negative (-) in plasma based on the detection of SNVs previously identified in tumor tissue. Results: Variants were identified in 99% of tumors (n = 144) with a median of 4 SNVs/sample (range 1-24) and all post-operative plasma samples were successfully profiled. Pts with detectable ctDNA (n = 12) displayed a significantly shorter 2-year relapse-free survival (RFS; 17% vs 88%; HR 10.3; 95% CI 2.3-46.9; p &lt; 0.00001), time to recurrence (TTR; HR 20.6; 95% CI 3.1-139.0; p &lt; 0.00001) and overall survival (OS; HR 3.4; 95% CI 0.5-25.8; p = 0.041) than ctDNA- pts (n = 132). 11 (92%) of ctDNA+ pts developed recurrence compared to 9 (7%) of ctDNA- pts. Monitoring multiple variants doubled sensitivity of MRD detection compared to tracking a single driver mutation. TTR was shorter in ctDNA+ vs ctDNA- Stage II (HR 23.1, 95% CI 0.28-1900.4; p &lt; 0.00001) and stage III pts (HR 17.9; 95% CI 2.7-117.3, p &lt; 0.00001). TTR of Stage II and III ctDNA- pts was similar (p = 0.7). Conclusions: Our results indicate that ctDNA analysis can detect MRD within days after complete resection of CRC and accurately identifies pts at high risk of recurrence in both Stage II and III CRC. MRD detection via ctDNA sequencing may allow personalization of adjuvant treatment strategies.