Pneumatic displacement with intravitreal tPA injection versus vitrectomy with sub retinal tPA injection in small and medium sub macular hemorrhages- a multicenter comparative study.

PURPOSE: Comparing between the visual outcomes and post operative complications of two surgical treatments for sub macular hemorrhage, pars plana vitrectomy with tissue plasminogen activator (tPA) injection procedure, and pneumatic displacement of submacular hemorrhage with intravitreal tPA injection. METHODS: A retrospective chart review of patients with sub macular hemorrhage (SMH) was performed. Data was collected from 150 patients with sub macular hemorrhage. Patients were followed up from the day of admission and up to a year post surgery. Evaluation included visual acuity, optical coherence tomography (OCT), fundus examination and rates of complications. RESULTS: Pars plana vitrectomy procedure has showed a better visual outcome in small SMH. Comparing complications between the two treatment modalities, no significant difference has been found in the study. CONCLUSIONS: Pars plana vitrectomy and tPA showed a clear advantage with a trend of better visual acuity as well as a significant predictor to better visual acuity for small and medium sub macular hemorrhage.

Improved outcome with individualised antifibrinolytic therapy: what is the evidence?

Viscoelastic haemostatic testing (VHT) has been used to determine hyperfibrinolysis and hypofibrinolysis. When modified by addition of tissue plasminogen activator (tPA), VHT has been suggested to assess responses to antifibrinolytic therapy and to estimate the concentration of tranexamic acid in patients undergoing cardiac surgery. Despite some evidence that tPA-modified VHT might allow individualisation of antifibrinolytic therapy, further studies are warranted to prove its clinical benefit for postsurgical bleeding, transfusion of blood products, and thromboembolic events.

Acute ischemic stroke with a diagnosis of Marfan syndrome: A report of 3 cases in multifaceted settings.

RATIONALE: Marfan syndrome (MFS), which is a dominantly inherited connective tissue disease resulting from a mutation in the FBN1 gene, exhibits variable manifestations affecting the cardiovascular, musculoskeletal, ophthalmologic, and pulmonary systems. Notably, neurologic deficiency, which involves ischemic or hemorrhagic stroke, is a rare but severe manifestation. The safety of rt-PA treatment for ischemic stroke caused by MFS is still under discussion. PATIENT CONCERNS: In the current report, we discuss 3 atypical MFS cases presented as acute ischemic stroke, compared to those exhibiting cardiovascular and musculoskeletal abnormalities. DIAGNOSES: Three patients were diagnosed with acute ischemic stroke accompanied by MFS based on clinical manifestations, imaging examinations, and genetic testings. INTERVENTIONS: The first case underwent intravenous thrombolytic therapy with rt-PA, the second case received antiplatelet therapy, and the third case received anticoagulant therapy and perfusion therapy. OUTCOMES: The neurologic deficiency of all three patients showed improvement upon discharge, and there were no symptoms of recurrence observed during the follow-up period. LESSONS SUBSECTIONS: MFS is a rare etiology in young people with embolic stroke of undetermined source. Physicians should take MFS into consideration when they observe the characteristic symptoms during a consultation. The potential pathogenesis of ischemic stroke secondary to MFS may include cardio-embolism, arterial dissection, and hypoperfusion. Although intravenous thrombolysis is a promising therapy to treat acute ischemic stroke, further examinations should be conducted to rule out contraindications in patients with a suspicion of MFS.

Changes and significance of the fibrinolytic system following two pulmonary thromboembolisms in a rabbit model.

In this study, we examined the changes in the fibrinolytic system in a rabbit model of two acute pulmonary thromboembolisms (PTE). Fourteen healthy adult New Zealand white rabbits were divided into three groups: the single PTE group (five rabbits), the double PTE group (five rabbits), and the control group (four rabbits). A rabbit model of acute pulmonary embolism was established, and immunohistochemistry and polymerase chain reaction (PCR) were performed on tissue plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1) in plasma, and pulmonary embolism tissue. Plasma results: 1) t-PA levels: one hour following the initial modeling, the levels of t-PA in the modeling groups were significantly lower than those in the control group (P<0.05). In addition, the t-PA levels in the double PTE group were found to be lower after the modeling, as compared to the pre-modeling period (P<0.05). One hour after the second modeling, the double PTE group had lower t-PA levels compared to the control group (P<0.05). However, t-PA rebounded two hours after modeling in the double PTE group. One week after the second modeling, the double PTE group had higher t-PA levels compared to the other two groups (P<0.05). 2) PAI-1 results: one hour after the initial modeling, PAI-1 levels in the two modeling groups were lower compared to the pre-modeling period and control groups (P<0.05). Two hours following modeling, PAI-1 levels in both modeling groups were lower compared to the control group (P<0.05). PAI-1 levels were lower in the double PTE group one and two hours after the second modeling compared to the other two groups and pre-modeling period (P<0.05). 3) The immunohistochemistry results: the expression of PAI-1 decreased in the two modeling groups, while t-PA expression increased compared to the control group. 4) PCR results: t-PA mRNA expression did not differ among the three groups. The PAI-1 mRNA expression was lower in the two PTE groups compared to the control group. We conclude that in the early stages of PTE, the local fibrinolytic activity of the thrombus is increased, which is favorable for thrombolysis. However, as the thrombus persists, the activity of the fibrinolytic system is inhibited, contributing to the development of chronic thromboembolic pulmonary hypertension.

Cerebral autoregulation: A reliable predictor of prognosis in patients receiving intravenous thrombolysis.

AIMS: To investigate the characteristics of dynamic cerebral autoregulation (dCA) after intravenous thrombolysis (IVT) and assess the relationship between dCA and prognosis. METHODS: Patients with unilateral acute ischemic stroke receiving IVT were prospectively enrolled; those who did not were selected as controls. All patients underwent dCA measurements, by quantifying the phase difference (PD) and gain, at 1-3 and 7-10 days after stroke onset. Simultaneously, two dCA-based nomogram models were established to verify the predictive value of dCA for patients with mild-to-moderate stroke. RESULTS: Finally, 202 patients who received IVT and 238 who did not were included. IVT was positively correlated with higher PD on days 1-3 and 7-10 after stroke onset. PD values in both sides at 1-3 days after stroke onset and in the affected side at 7-10 days after onset were independent predictors of unfavorable outcomes in patients who received IVT. Additionally, in patients with mild-to-moderate stroke who received IVT, the dCA-based nomogram models significantly improved the risk predictive ability for 3-month unfavorable outcomes. CONCLUSION: IVT has a positive effect on dCA in patients with acute stroke; furthermore, dCA may be useful to predict the prognosis of patients with IVT.

Left ventricular systolic dysfunction predicts clinical prognosis in patients with acute ischemic stroke after intravenous thrombolysis.

BACKGROUND: Although intravenous recombinant tissue plasminogen activator (rt-PA) thrombolysis is the most effective early treatment for acute ischemic stroke (AIS), outcomes vary greatly among patients. Left ventricular systolic dysfunction (LVSD) is prone to distant organ ischemia and may be a predictor for poor prognosis in AIS patients undergoing intravenous thrombolysis (IVT). Our aim was to investigate the predictivity of LVSD diagnosis (as measured by left ventricular ejection fraction (LVEF)) on 90-day clinical outcomes in AIS patients undergoing thrombolysis. METHODS: The current prospective cohort study continuously enrolled 273 AIS patients from the National Stroke Prevention and Treatment Engineering Management Special Database who underwent IVT and completed echocardiography within 24 h of admission between 2021 and 2023. LVSD was examined by evaluation of the echocardiographic LVEF values using Simpson's biplane method of discs in line with international guidelines, and defined as a LVEF value < 50%. Multivariable ordinal logistic regression model was performed to analyze the association between LVEF and functional outcome at 3 months. Restricted cubic spline (RCS) was used to examine the shape of the dose-response association between reduced LVEF and poor functional outcomes. Subgroup analysis was also employed to further verify the reliability and practicability of the results. RESULTS: Baseline data analysis showed LVSD patients had more comorbidities including on multivariate analyses, LVSD (OR 2.78, 95% CI 1.23 to 6.24, P=0.014), pre-existing diabetes mellitus (OR 2.08, 95% CI 1.11 to 3.90, P=0.023) and NIHSS on arrival (OR 1.31, 95% CI 1.21 to 1.49, P<0.001) were independent predictors of poor functional outcomes (mRS ≥ 3) at 3 months. Multivariable-adjusted spline regression indicated a linear dose-response association between LVEF after IVT and poor functional outcomes (p for linearity < 0.001), with the optimal cutoff values of LVEF being 0.48. CONCLUSIONS: Our finding indicated that AIS patients with LVSD after IVT had poorer outcomes, suggesting the need to monitor and optimize LVEF in stroke management.

Glucose Control and Risk of Symptomatic Intracerebral Hemorrhage Following Thrombolysis for Acute Ischemic Stroke: A SHINE Trial Analysis.

BACKGROUND AND OBJECTIVES: Baseline hyperglycemia is associated with worse outcomes in acute ischemic stroke (AIS), including higher risk of symptomatic intracerebral hemorrhage (sICH) following treatment with thrombolysis. Prospective data are lacking to inform management of post-thrombolysis hyperglycemia. In a prespecified analysis from the Stroke Hyperglycemia Insulin Network Effort (SHINE) trial of hyperglycemic stroke management, we hypothesized that post-thrombolysis hyperglycemia is associated with a higher risk of sICH. METHODS: Hyperglycemic AIS patients <12 hours onset were randomized to intensive insulin (target range 80-130 mg/dL) vs standard sliding scale (80-179 mg/dL) over a 72-hour period, stratified by treatment with thrombolysis. Three board-certified vascular neurologists independently reviewed all sICH events occurring within 7 days, defined by neurologic deterioration of ≥4 points on the NIH Stroke Scale (NIHSS). Associations between blood glucose control and sICH were analyzed using logistic regression accounting for NIHSS, age, systolic blood pressure, onset to thrombolysis time, and endovascular therapy (odds ratios [OR], 95% CI). Additional analysis compared patients in a high-risk group (age older than 60 years and NIHSS ≥8) vs all others. Categorical variables and outcomes were compared using the χ2 test (p < 0.05). RESULTS: Of 1151 SHINE participants, 725 (63%) received thrombolysis (median age 65 years, 46% women, 29% Black, 18% Hispanic). The median NIHSS was 7, baseline blood glucose was 187 (interquartile range 153-247) mg/dL, and 80% were diabetic. Onset to thrombolysis time was 2.2 hours (1.6-2.9). Post-thrombolysis sICH occurred in 3.6% (3.0% intensive vs 4.3% standard glucose control, OR 1.10, 0.60-2.01, p = 0.697). In the first 12 hours, every 10 mg/dL higher glucose increased the odds of sICH (OR 1.08, 1.03-1.14, p = 0.004), and a greater proportion of glucose measures in the normal range (80-130 mg/dL) decreased the odds of sICH (0.89, 0.80-0.99, p = 0.030). These associations were strongest in the high-risk group (age older than 60 years and NIHSS ≥8). DISCUSSION: In this prespecified analysis from the SHINE trial, intensive insulin therapy was not associated with a reduced risk of post-thrombolysis sICH compared with standard sliding scale. However, early post-thrombolysis hyperglycemia was associated with a higher risk of sICH overall, particularly in older patients with more severe strokes. Further prospective research is warranted to address the risk of sICH in hyperglycemic stroke patients undergoing endovascular therapy. TRIAL REGISTRATION INFORMATION: NCT01369069.

Utilization of a Supraglottic Airway Device for Airway Rescue and Tamponade of an Oropharyngeal Hemorrhage After Systemic Thrombolysis for an Acute Ischemic Stroke: A Case Report.

A 39-year-old man presented for mechanical thrombectomy after receiving systemic tissue plasminogen activator (tPA) for a basilar artery occlusion. The anesthesiology team was initially unable to intubate the patient due to oropharyngeal bleeding and a large epiglottis. Two-handed, 2-provider mask ventilation with an oral airway proved difficult. The team successfully placed a supraglottic airway (SGA) through which an oral endotracheal tube (ETT) was advanced over a fiberoptic bronchoscope into the trachea. The SGA remained overnight with the cuff inflated to tamponade the bleeding. The ETT was exchanged over an airway exchange catheter on postoperative day 1 without further airway complications.

Spurious Hyperphosphatemia in a Patient with Chronic Kidney Disease - a Rare Case of Alteplase Contamination.

Spurious hyperphosphatemia, a rare occurrence, typically arises from substances in a patient's blood interfering with the colorimetric method for serum phosphate measurement. We present a case of factitious hyperphosphatemia caused by alteplase-contaminated blood samples in an 88-year-old CKD patient on hemodialysis, leading to misleadingly high phosphorus levels. Thorough investigations ruled out other etiologies, highlighting the necessity of stringent adherence to blood collection protocols to prevent sample contamination and avert erroneous laboratory results. This unique cause of hyperphosphatemia should be considered in the differential diagnosis when encountering unexplained elevations in phosphorus levels, particularly in the context of normal blood calcium levels.

What does cognitive screening reveal about early cognitive performance following endovascular clot retrieval and intravenous thrombolysis in acute ischaemic stroke?

Background Little is known regarding cognitive outcomes following treatment with endovascular clot retrieval (ECR) and intravenous tissue plasminogen activator (t-PA). We aimed to determine if there were any differences on a measure of cognitive screening between patients treated with ECR, t-PA, and those who were managed conservatively. Methods The medical records of ischaemic stroke patients admitted to Monash Medical Centre between January 2019 and December 2019 were retrospectively reviewed. Information extracted from medical records included age, sex, National Institutes of Health Stroke Scale at presentation, location of occlusion, treatment type, medical history, and cognitive screening performance measured by the Montreal Cognitive Assessment (MoCA). Results Eighty-two patients met the inclusion criteria (mean age = 66.5 ± 13.9; 49 male, 33 female). Patients treated with ECR performed significantly better on the MoCA (n = 36, 24.1 ± 4.3) compared to those who were managed conservatively (n = 26, 20.7 ± 5.5). Performance for patients treated with t-PA (n = 20, 23.9 ± 3.5) fell between the ECR and conservative management groups, but they did not significantly differ from either. Conclusion Our retrospective chart review found that ischaemic stroke patients treated with ECR appear to perform better on cognitive screening compared to patients who are managed conservatively. We also found that patients treated with ECR and t-PA appear to have similar cognitive screening performances in the acute stages following ischaemic stroke, although this finding is likely to have been impacted by group differences in stroke characteristics and may reflect the possibility that the ECR group performed better than expected based on their stroke severity.

A challenging issue in COVID-19 infection: The relationship between PA1-1 and TAFI levels in patients with coagulation disorder: A retrospective and observational study.

COVID-19 disrupts the balance between coagulation and fibrinolysis. Especially in the clinical course of serious disease, plasminogen activator inhibitor-1 (PAI-1), thrombin activatable fibrinolysis inhibitor (TAFI), and tissue plasminogen activator levels increase in association with hypercoagulable state and hypofibrinolysis. This explains the increased incidence of thrombosis seen in COVID-19 infection. In this study, we aimed to examine the changes in PAI-1 and TAFI levels of COVID-19 patients. Department of Infectious Diseases and Clinical Microbiology, University of Health Sciences, Diskapi Yildirim Beyazit Training and Research Hospital-Ankara Turkey, between April 1 and May 7, 2021. Patients who were diagnosed with COVID-19 were included in this retrospective study. TAFI and PAI-1 levels were analyzed from the samples that had been stored at -80 °C formerly. One hundred thirty-five patients diagnosed with COVID-19 and followed up in the service or intensive care unit were included in the study. Thirty-four (25.2%) patients required follow-up in the intensive care unit. Mortality rate was 10.4%, the coagulation tests of these patients were also compared. PA1-1 levels were found to be statistically significantly higher in intensive care unit patients (median: 133 pg/mL vs 31 pg/mL; P < .001), and there was no significant difference in TAFI levels (median:7.31 ng/mL vs 9.80 ng/mL; P = .171) between the 2 groups. TAFI levels were found to be higher in patients who died. In COVID-19 infection, as the severity of the disease increases, the coagulation balance deteriorates and eventually a hypercoagulable state occurs with an increase in PAI-1 and TAFI levels. Markers such as PAI and TAFI can be illuminating in further studies in determining prognosis and mortality and developing new treatment options.

The Janus face of endogenous neuronal tPA: promoting self-protection and worsening the death of neighboring neurons.

Recombinant tissue-type plasminogen activator (r-tPA/Actilyse) stands as the prevailing pharmacological solution for treating ischemic stroke patients, of whom because their endogenous circulating tPA alone is not sufficient to rescue reperfusion and to promote favorable outcome. Beyond the tPA contributed by circulating endothelial cells and hepatocytes, neurons also express tPA, sparking debates regarding its impact on neuronal fate ranging from pro-survival to neurotoxic properties. In order to investigate the role of neuronal tPA during brain injuries, we developed models leading to its conditional deletion in neurons, employing AAV9-pPlat-GFP and AAV9-pPlat-Cre-GFP along with tPA floxed mice. These models were subjected to N-methyl-D-aspartate (NMDA)-induced excitotoxicity or thromboembolic ischemic stroke in mice. Initially, we established that our AAV9 constructs selectively transduce neurons, bypassing other brain cell types. Subsequently, we demonstrated that tPA-expressing neurons exhibit greater resistance against NMDA-induced excitotoxicity compared to tPA negative neurons. The targeted removal of tPA in neurons heightened the susceptibility of these neurons to cell death and prevented a paracrine neurotoxic effect on tPA non-expressing neurons. Under ischemic conditions, the self-neuroprotective influence of tPA encompassed both excitatory (GFP+/Tbr1+) and inhibitory (GFP+/GABA+) neurons. Our data indicate that endogenous neuronal tPA is a protective or deleterious factor against neuronal death in an excitotoxic/ischemic context, depending on whether it acts as an autocrine or a paracrine mediator.

Risk Factors Associated With Exclusion of Obese Patients Ischemic Stroke With a History of Smoking From Thrombolysis Therapy.

The objective of this study is to determine risk factors that may contribute to exclusion decision from recombinant tissue plasminogen activator (rtPA) in patients with acute ischemic stroke (AIS) with a combined current or history of smoking and obesity. This study was conducted on data from 5469 patients with AIS collected from a regional stroke registry. Risk factors associated with inclusion or exclusion from rtPA were determined using multivariate logistic regression analysis. The adjusted odds ratios and 95% confidence interval for each risk factor were used to predict the increasing odds of an association of a specific risk factor with exclusion from rtPA. In the adjusted analysis, obese patients with AIS with a history of smoking (current and previous) excluded from rtPA were more likely to present with carotid artery stenosis (OR = 0.069, 95% CI 0.011-0.442), diabetes (OR = 0.604, 95% CI 0.366-0.997), higher total cholesterol (OR = 0.975, 95% CI 0.956-0.995), and history of alcohol use (OR = 0.438, 95% CI 0.232-0.828). Higher NIHSS score (OR = 1.051, 95% CI 1.017-1.086), higher triglycerides (OR = 1.004, 95% CI 1.001-1.006), and higher high-density lipoprotein (OR = 1.028, 95% CI 1.000-1.057) were associated with the inclusion for rtPA. Our findings reveal specific risk factors that contribute to the exclusion of patients with AIS with a combined effect of smoking and obesity from rtPA. These findings suggest the need to develop management strategies to improve the use of rtPA for obese patients with AIS with a history of smoking.

Impact of Local Tailoring on Acute Stroke Care in 21 Disparate Emergency Departments: A Prospective Stepped Wedge Type III Hybrid Effectiveness-Implementation Study.

BACKGROUND: Faster delivery of tPA (tissue-type plasminogen activator) results in better health outcomes for eligible patients with stroke. Standardization of stroke protocols in emergency departments (EDs) has been difficult, especially in nonstroke centers. We measured the effectiveness of a centrally led implementation strategy with local site tailoring to sustain adherence to an acute stroke protocol to improve door-to-needle (DTN) times across disparate EDs in a multihospital health system. METHODS: Prospective, type III hybrid effectiveness-implementation cohort study measuring performance at 21 EDs in Utah and Idaho (stroke centers [4]/nonstroke centers [17]) from January 2018 to February 2020 using a nonrandomized stepped-wedge design, monthly repeated site measures and multilevel hierarchical modeling. Each site received the implementation strategies in 1 of 6 steps providing control and intervention data. Co-primary outcomes were percentage of DTN times ≤60 minutes and median DTN time. Secondary outcomes included percentage of door-to-activation of neurological consult times ≤10 minutes and clinical effectiveness outcomes. Results were stratified between stroke and nonstroke centers. RESULTS: A total of 855 474 ED patient encounters occurred with 5325 code stroke activations (median age, 69 [IQR, 56-79] years; 51.8% female patients]. Percentage of door-to-activation times ≤10 minutes increased from 47.5% to 59.9% (adjusted odds ratio, 1.93 [95% CI, 1.40-2.67]). A total of 615 patients received tPA of ≤3 hours from symptom onset (median age, 71 [IQR, 58-80] years; 49.6% female patients). The percentage of DTN times ≤60 minutes increased from 72.5% to 86.1% (adjusted odds ratio, 3.38, [95% CI, 1.47-7.78]; stroke centers (77.4%-90.0%); nonstroke centers [59.3%-72.1%]). Median DTN time declined from 46 to 38 minutes (adjusted median difference, -9.68 [95% CI, -17.17 to -2.20]; stroke centers [41-35 minutes]; nonstroke centers [55-52 minutes]). No differences were observed in clinical effectiveness outcomes. CONCLUSIONS: A centrally led implementation strategy with local site tailoring led to faster delivery of tPA across disparate EDs in a multihospital system with no change in clinical effectiveness outcomes including rates of complication. Disparities in performance persisted between stroke and nonstroke centers.

Comprehensive Review of Tenecteplase for Thrombolysis in Acute Ischemic Stroke.

Although intravenous thrombolysis with alteplase remains the primary treatment for acute ischemic stroke, tenecteplase has shown potential advantages over alteplase. Animal studies have demonstrated the favorable pharmacokinetics and pharmacodynamics of tenecteplase. Moreover, it is easier to administer. Clinical trials have demonstrated that tenecteplase is not inferior to alteplase and may even be superior in cases of acute ischemic stroke with large vessel occlusion. Current evidence supports the time and cost benefits of tenecteplase, suggesting that it could potentially replace alteplase as the main option for thrombolytic therapy, especially in patients with large vessel occlusion.

Point-of-care testing for tranexamic acid efficacy: a proof-of-concept study in cardiac surgical patients.

BACKGROUND: Low-dose tranexamic acid (TXA) has been recently recommended for cardiopulmonary bypass (CPB) to reduce associated complications. Although point-of-care laboratory tests for TXA concentrations are unavailable, a novel TPA-test on the ClotPro® system can measure TXA-induced inhibition of fibrinolysis. We evaluated the performance of the TPA-test in vitro and in patients undergoing surgery requiring CPB. METHODS: Blood samples were obtained from six volunteers for in vitro evaluation of tissue plasminogen activator (tPA)-triggered fibrinolysis and the effects of TXA. This was followed by an observational study in 20 cardiac surgery patients to assess clinical effects of TXA on the TPA-test. RESULTS: Hyperfibrinolysis induced by tPA was inhibited by TXA ≥2 mg L-1 in a concentration-dependent manner, and was completely inhibited at TXA ≥10 mg L-1. In patients undergoing CPB, antifibrinolytic effect was detectable on TPA-test parameters after a 0.1 g bolus of TXA at the end of CPB, and complete inhibition of fibrinolysis was obtained with TXA ≥0.5 g. The antifibrinolytic effects of 1 g TXA on TPA-test parameters were gradually attenuated over 18 h after surgery. However, the fibrinolytic inhibition continued in four patients with estimated glomerular filtration rate (eGFR) ≤30 ml min-1 1.73 m-2. The eGFR had strong correlations with TPA-test parameters at 18 h after surgery (r=0.86-0.92; P<0.0001). CONCLUSIONS: The TPA-test is sensitive to low concentrations of TXA and serves as a practical monitoring tool for postoperative fibrinolytic activity in cardiac surgery patients. This test might be particularly useful in patients with severe renal impairment.

Post-Translational Oxidative Modifications of Hemostasis Proteins: Structure, Function, and Regulation.

Reactive oxygen species (ROS) are constantly generated in a living organism. An imbalance between the amount of generated reactive species in the body and their destruction leads to the development of oxidative stress. Proteins are extremely vulnerable targets for ROS molecules, which can cause oxidative modifications of amino acid residues, thus altering structure and function of intra- and extracellular proteins. The current review considers the effect of oxidation on the structural rearrangements and functional activity of hemostasis proteins: coagulation system proteins such as fibrinogen, prothrombin/thrombin, factor VII/VIIa; anticoagulant proteins - thrombomodulin and protein C; proteins of the fibrinolytic system such as plasminogen, tissue plasminogen activator and plasminogen activator inhibitor-1. Structure and function of the proteins, oxidative modifications, and their detrimental consequences resulting from the induced oxidation or oxidative stress in vivo are described. Possible effects of oxidative modifications of proteins in vitro and in vivo leading to disruption of the coagulation and fibrinolysis processes are summarized and systematized, and the possibility of a compensatory mechanism in maintaining hemostasis under oxidative stress is analyzed.

Preoperative co-application of bevacizumab and tissue plasminogen activator in vitrectomy for proliferative diabetic retinopathy.

PURPOSE: To investigate the clinical benefits of the co-application of bevacizumab and tissue plasminogen activator as adjuncts in the surgical treatment of proliferative diabetic retinopathy. METHODS: Patients who underwent vitrectomy for proliferative dia-betic retinopathy complications were preoperatively given in-travitreal injection with either bevacizumab and tissue plasminogen activator (Group 1) or bevacizumab alone (Group 2). Primary outcomes were surgery time and number of intraoperative iatrogenic retinal breaks. Secondary outcomes included changes in the best-corrected visual acuity and postoperative complications at 3 months postoperatively. RESULTS: The mean surgery time in Group 1 (52.95 ± 5.90 min) was significantly shorter than that in Group 2 (79.61 ± 12.63 min) (p<0.001). The mean number of iatrogenic retinal breaks was 0.50 ± 0.59 (0-2) in Group 1 and 2.00 ± 0.83 (0-3) in Group 2 (p<0.001). The best-corrected visual acuity significantly improved in both groups (p<0.001). One eye in each group developed retinal detachment. CONCLUSION: Preoperative co-application of bevacizumab and tissue plasminogen activator as adjuncts in the surgical treatment of proliferative diabetic retinopathy shortens the surgery time and reduces the number of intraoperative iatrogenic retinal breaks.