Development Of Ischemic Complications Research Articles

Impact of analgesic regimen on patient outcome following subarachnoid hemorrhage: positive adjuvant effects of metamizole

Introduction Various analgesics are used to control intense headaches in patients following subarachnoid hemorrhage. In addition to pain control, it has been shown that some analgesics can affect various pathophysiological cascades. Therefore, we devised a study to assess whether the use of metamizole has a significant impact on the development of ischemic complications, hydrocephalus, and the overall outcome in patients following aneurysmal subarachnoid hemorrhage in the context of the other non-opioids and opioids effects. Methods In our retrospective, single-center cohort study, we enrolled 192 patients diagnosed with subarachnoid hemorrhage. We recorded their initial clinical status, comorbidities, and the daily dosage of analgesics over 14 days of hospitalization after the onset of subarachnoid hemorrhage. Using univariate and subsequent multivariate logistic regression analysis, we assessed the influence of various factors, including analgesics, on the development of delayed cerebral ischemia and hydrocephalus, as well as on 2-week and 6-month outcomes. Results Although the administration of non-opioids, in general, had no effect on the development of delayed cerebral ischemia or hydrocephalus, the use of metamizole as the main analgesic was associated with a significantly lower chance of poor outcome at both 2-weeks and 6-months, as well as the development of delayed cerebral ischemia. As opioids were indicated primarily for analgosedation in mechanically ventilated patients with poor clinical status, their usage was associated with a significantly higher chance of poor outcome, delayed cerebral ischemia, and hydrocephalus. Conclusion Our results suggest that the prescription of metamizole may be associated with better outcomes and a lower chance of delayed cerebral ischemia development in patients after subarachnoid hemorrhage. Considering the retrospective nature of our study and the limited worldwide availability of metamizole due to its prohibition in some countries, our results do not demonstrate a clear benefit but rather justify the need for subsequent prospective studies.

Prevention of complication in cerebral aneurysm microsurgery, associated with their non-radical clipping

Objective ‒ to analyze the effectiveness of intraoperative contact Doppler, repositioning the clip on the aneurysm and pilot clipping of the cervical aneurysm as the main methods of prevention of inadequate clipping of the cervical aneurysm in patients with intraoperative rupture of aneurysms. Materials and methods. Due to the use of intraoperative contact ultrasound Doppler control it was possible to avoid inadequate clipping of cerebral aneurysms in 16 cases, of which in 12 (75.00 %) cases ‒ incomplete clipping of cerebral aneurysms, in 3 (18.75 %) cases ‒ compression of the aneurysm’s artery-carrier, in 1 (6.25 %) case ‒ slipping of the clip with cerebral aneurysm. Perioperative examination of patients, in addition to intraoperative contact ultrasound Doppler control of radical clipping cerebral aneurysms, included clinical and neurological examination, computed tomography of the brain, cerebral angiography, ultrasound duplex scanning of the main vessels of the head and neck. In the analysis of observations of inadequate clipping of cerebral aneurysms (according to contact intraoperative Doppler), the following parameters were considered: size, location of cerebral aneurysm, timing of surgery after subarachnoid hemorrhage, anatomical forms of intracranial hemorrhage. Results. The purpose of the operations was to devascularize saccular aneurysm to prevent its re-rupture, to reduce the mass effect caused by intracerebral hematoma; reduction of intracranial pressure, rehabilitation of basal cisterns of the brain., But in the postoperative period there was a tendency to worsen the results of treatment, the appearance of focal neurological symptoms on the background of cerebral vasospasm with subsequent development of ischemic complications in patients with III‒V degree according to the Hunt‒Hess Scale on admission, in patients with prolonged temporary clipping of the cerebral aneurysm-artery and prolonged mechanical manipulation of the cerebral arteries and cerebral aneurysm. It should be noted that all patients in our sample, with complicated clipping of cerebral saccular aneurysms, had an intraoperative rupture of the MA, which complicated the process of clipping the saccular aneurysm and prolonged the time of surgery and was one of the inducers of postoperative aggravating consequences. There was a tendency to worsen the results of treatment in patients with III–IV degree according to the Hunt‒Hess Scale. Thus, patients with 1 point according to the Glasgow Outcome Scale, there were 2 patients who had II and III degrees according to Hunt–Hess Scale at hospitalization; among discharged patients with 3 point according to Glasgow Outcome Scale was dominated by patients from the second century according to Hunt‒Hess Scale at hospitalization, among patients with 5 point according to Glasgow Outcome Scale dominated patients who had I degree according to the Hunt‒Hess Scale at hospitalization. Conclusions. Inadequate clipping of the cervix cerebral aneurysm is the main type of non-hemorrhagic complications in the surgery of cerebral aneurysms. The Inadequate clipping of the cervix of the cerebral aneurysm includes the presence of residual blood flow in the cerebral aneurysm after its clipping, stenosis/compression of the main and perforating cerebral arteries with a clip, slipping of the clip from the aneurysm. Among the factors influencing the radical and adequate clipping of the cervix cerebral aneurysm are the size, location of the aneurysm, atherosclerotic lesions of the walls of the arteries and neck of the aneurysm and transferred subarachnoid hemorrhage. Reliable methods of prevention of inadequate clipping of saccular aneurysm are the use of intraoperative Doppler blood flow control, pilot clipping of complex aneurysms, optimization and individualization of surgical access. Aggravating factors that lead to unsatisfactory results of treatment of patients and negative clinical dynamics after the operation of clipping cerebral saccular aneurysm are: severe condition of the patient before surgery (III‒V gr. according to the Hunt‒Hess Scale), severe cerebral edema, intraoperative rupture of saccular aneurysm, long-term mechanical manipulations on cerebral arteries (long-term temporary clipping of saccular aneurysm, isolation of saccular aneurysm and «neighboring» cerebral arteries from arachnoid adhesions, frequent repositioning of the clip).

Tissue Factor Is Internalized by Platelets Through Activation of RhoA and PI3-Kinase Promoting Reversible Cytoskeletal Assembly,

Abstract 3264TF associated with platelets may play a critical role in the development of ischemic complications at sites of vascular damage. Platelets can internalize and store tissue factor-rich microvesicles from human origin (hTF), a process that can be potentiated by serotonin (5-HT) (Galan et al, Thromb Haemost. 102:511, 2009). There is limited knowledge on the mechanisms involved in the uptake, redistribution and functional expression of TF by platelets. We have investigated the mechanisms implied in the uptake and traffic of hTF with especial attention to CD36 and the 5HT transporter receptor (SERT), but also to the involvement of PI3-kinase, small GTPases (RhoA) and modifications of cytoskeletal organization during vesicular trafficking. Isolated platelets were exposed to hTF for up to 10 min. Cytoskeletal assembly and activation of RhoA were analyzed by electrophoresis and ELISA, respectively. Aggregometry and ultrastructural microscopy were used to assess platelet activation and hTF uptake. Protein arrays were used to evaluate changes in signaling molecules induced by hTF. In addition, inhibitory strategies to block GPIIbIIIa (Reopro), the scavenger receptor GPIV (anti-CD36), the SERT (S-Citalopram, SCit), and PI3-kinase (Wortmannin, Wo) were applied to platelets prior exposure to hTF. Internalization of hTF resulted in reversible actin polymerization and association of contractile proteins (alpha-actinin, actin binding protein and myosin) to the cytoskeleton, being maximal at 1 min. Maximal activation of RhoA occurred at 1 min, decreasing gradually afterwards, while activation of PI3-kinase occurred later (at 5 min). Screening of signaling proteins revealed activation of Akt, ERK1/2, and SNAP-25, among others. All inhibitory strategies fully prevented platelet aggregation to hTF. Uptake of hTF was slightly prevented by Reopro, while both anti-CD36 and Wo partially inhibited hTF uptake and, interestingly, SCit was the most efficient. We conclude that uptake of hTF by platelets promotes activation of specific signaling molecules with reversible cytoskeletal assembly and membrane fusion. While it may be difficult to design specific strategies to prevent the activation of small GTPases, cytoskeletal arrangements or membrane fusion specifically for platelets, our results indicate that the CD36 scavenger receptor and the 5-HT transporter (SERT) may become realistic therapeutic targets to prevent or reduce the association of TF to platelets and hence its possible prothrombotic action.Grants: SAF2009-10365, Red HERACLES RD06/0009/1003 Disclosures:No relevant conflicts of interest to declare.

Development of Ischemic Complications in Patients With Giant Cell Arteritis Presenting With Apparently Isolated Polymyalgia Rheumatica

Several studies suggest that patients with giant cell arteritis (GCA) presenting with isolated polymyalgia rheumatica (PMR) with no cranial symptoms are at low risk of suffering GCA-related ischemic events. However, the issue remains controversial. In the current study we assessed the development of ischemic events in a large series of GCA patients who suffered from apparently isolated PMR during the main course of their disease. One hundred GCA patients presenting with PMR only for at least 2 months were selected from among 347 individuals with biopsy-proven GCA. Clinical manifestations and their chronologic appearance before diagnosis were recorded. Seventy-three patients presented with isolated PMR for a median of 8 months (range, 2 mo-5 yr) and later developed cranial symptoms for a median of 3 weeks (range, 0 wk-1 yr), which eventually led to GCA diagnosis (Group 1). The remaining 27 patients, after presenting a self-limiting course of dismissed mild cranial symptoms lasting for a median of 2 weeks (range, 1 wk-4 mo), developed PMR, which was their chief complaint for a median of 3 months (range, 2 mo-1.5 yr) and the reason for medical evaluation (Group 2). Twenty (27.4%) patients in Group 1 suffered disease-related ischemic complications at the time of diagnosis. No patient in Group 2 developed ischemic events. Patients with GCA presenting with apparently isolated PMR are not a benign subset and have a significant risk of developing ischemic complications. Among them, the only patients who appear to be at low risk of developing ischemic events are those in whom a self-limiting episode of cranial symptoms can be recorded.

Double Supply to Left Anterior Descending Artery by Additional Saphenous Vein Graft in Internal Thoracic Artery Malperfusion Syndrome

Internal thoracic artery (ITA) grafting to the left anterior descending artery (LAD) may have catastrophic consequences and can be fatal due to "ITA malperfusion syndrome." We have investigated the efficacy of a second graft in this syndrome. A total of 35 patients, 29 males (82.9%) and 6 females (17.1%), with a mean age of 53.0 +/- 8.7, (range: 38 to 70) undergoing coronary artery bypass grafting required a second supply to LAD due to ITA malperfusion syndrome. This was performed using a saphenous vein graft. The mean number of distal anastomosis was 2.7 +/- 0.45 per patient (range: 1 to 5). The decision for an additional grafting procedure was made in the first operation for 18 patients (51.4%) (Group I). For the remaining 17 patients (48.6%) (Group II), the additional grafting procedures were performed during a reoperation after the development of ischemic complications in the intensive care unit (ICU). The early mortality rate was 8.6% (3 of 35). Two patients had perioperative myocardial infarction (MI) (5.7%). The second vein graft proved to dramatically reduce the incidence of postoperative MI. Malignant refractory arrhythmias were recorded in 17 patients (48.6%). Twelve patients (34.3%) required inotropic support and seven patients (20%), all in Group II, required intra-aortic balloon pump (IABP) support. The average duration of IABP was 5 days +/- 1.8 days (range: 3 to 7). The necessity of IABP support was found to be statistically higher in the second group compared to the first one. Double supply to LAD using an additional saphenous vein graft is the treatment of choice for ITA malperfusion syndrome. The time interval between the first and the second grafts appears to be crucial for postoperative patient outcome.

Ischemic Complications of Distal Aortic Dissections: Open Surgical or Endovascular Management?

Acute aortic dissection is one of the most common catastrophic events that affects the aorta, and, even in the best of circumstances, morbidity and mortality remain high. The majority of aortic dissections involving the descending thoracic aorta can be successfully managed with medical therapy. However, even with aggressive medical therapy, the associated mortality approaches 20%, and a significant number of patients die within a year from complications related to the dissection. Operations for descending thoracic aortic dissection are reserved for patients who fail medical management and develop complications such as aneurysm formation, aortic rupture, branch vessel malperfusion, or refractory pain. Patients who require operative intervention for acute descending thoracic aortic dissections have a worse outcome, with mortality rates near 35%. Mortality is higher in patients who require operative intervention specifically for ischemic complications related to dissection. It is in this group of patients that new, less-invasive methods of endovascular treatment have been promoted with great enthusiasm. Furthermore, early success of endovascular techniques in treating ischemic complications of distal aortic dissection raises the question: Should such patients be managed with traditional open surgical operation or newer endovascular therapies? This article summarizes the anatomy and natural history of descending thoracic aortic dissection, focusing on the development of ischemic complications, comparing and contrasting the role of open surgical operation to endovascular therapy.

Ischemic Complications of Distal Aortic Dissections: Open Surgical or Endovascular Management?

-Acute aortic dissection is one of the most common catastrophic events that affects the aorta, and, even in the best of circumstances, morbidity and mortality remain high. The majority of aortic dissections involving the descending thoracic aorta can be successfully managed with medical therapy. However, even with aggressive medical therapy, the associated mortality approaches 20%, and a significant number of patients die within a year from complications related to the dissection. Operations for descending thoracic aortic dissection are reserved for patients who fail medical management and develop complications such as aneurysm formation, aortic rupture, branch vessel malperfusion, or refractory pain. Patients who require operative intervention for acute descending thoracic aortic dissections have a worse outcome, with mortality rates near 35%. Mortality is higher in patients who require operative intervention specifically for ischemic complications related to dissection. It is in this group of patients that new, less-invasive methods of endovascular treatment have been promoted with great enthusiasm. Furthermore, early success of endovascular techniques in treating ischemic complications of distal aortic dissection raises the question: Should such patients be managed with traditional open surgical operation or newer endovascular therapies? This article summarizes the anatomy and natural history of descending thoracic aortic dissection, focusing on the development of ischemic complications, comparing and contrasting the role of open surgical operation to endovascular therapy.

Clopidogrel: a selective inhibitor of platelet ADP receptors.

Platelets play a key role in the development of ischemic complications in the arterial circulation. Antiplatelet therapy has proven effective in the treatment and prevention of ischemic events. Numerous clinical studies have confirmed the therapeutic efficacy of aspirin to such a point that this antiplatelet agent has become the gold standard in clinical practice. Clopidogrel is a thienopyridine compound that inhibits platelet aggregation by selectively binding to adenylate cyclase-coupled ADP receptors. Results of a large, double-blind, randomized study (CAPRIE) confirm that administration of clopidogrel to patients with atherosclerotic vascular disease is more effective than aspirin in reducing the combined risk of ischemic stroke, myocardial infarction or vascular death. The present article highlights the importance of activation of platelets through ADP receptors and reviews the pharmacology and clinical studies of clopidogrel, a selective inhibitor of these mechanisms.

Evaluation of platelet membrane glycoproteins in coronary artery disease : consequences for diagnosis and therapy

Platelets play a fundamental role in atherogenesis and development of ischemic complications.1 2 3 Under physiological conditions, platelets do not interact with the vessel wall. Injury of vascular intima disrupts the antithrombotic properties of endothelium and exposes the blood to adhesive molecules of the subendothelium. Platelet adhesion to the damaged vessel wall is the first step in hemostasis and thrombosis.4 Platelet adhesion is followed by spreading and activation, resulting in release of granule components and aggregate formation.5 6 On initial contact, platelet glycoprotein (GP) Ib/V/IX complex binds to von Willebrand factor associated with collagen on the subendothelial surface (Figure 1⇓)4 5 and thus arrests the platelet on the vessel surface. The collagen receptor α2β1 is an important secondary receptor for platelet adhesion. α2β1-Collagen interaction leads to platelet activation and is critical for the spreading process involving the fibrinogen receptor GP IIb/IIIa to ensure close contact of the spread platelet with the surface.5 Other adhesion receptors, including the fibronectin receptor α5β1 and the laminin receptor α6β1, support and strengthen secondary adhesion (Figure 1⇓). The fibrinogen receptor GP IIb/IIIa is particularly important in platelet-platelet coadhesion, termed aggregation. This requires conformational changes in GP IIb/IIIa that allow binding of soluble fibrinogen to the platelet membrane (Figure 2⇓). Thus, fibrinogen bridging allows formation of platelet aggregates (Figure 2⇓).6 7 8 9 Figure 1. Platelet membrane glycoproteins and primary hemostasis. vWF indicates von Willebrand factor; Fn, fibronectin; Col, collagen; Lam, laminin; and AA, arachidonic acid. Figure 2. Platelet aggregation. Epi indicates epinephrine; Col, collagen; and Fg, fibrinogen. Platelet adhesion and aggregation induce intracellular signaling, which mediates several responses, such as formation and secretion of thromboxane A2 (TXA2), serotonin, and ADP6 (Figure …

Central conduction time as an index of ischaemia in subarachnoid haemorrhage

Central conduction time (CCT) has been measured in 12 healthy volunteers, and in 16 patients admitted to a neurosurgical unit following subarachnoid haemorrhage. Twelve of the patients were subsequently operated upon for the obliteration of an intracranial aneurysm. CCT has been found to have low standard deviation in control cases, and in the normal side following subarachnoid haemorrhage from aneurysms in the Circle of Willis, and to be prolonged during the development of ischaemic complications, either of the haemorrhage or following surgery. Evidence so far suggests that CCT may be useful as a monitor of developing ischaemia in association with surgery for subarachnoid haemorrhage.

Antifibrinolytic therapy in ruptured intracranial aneurysm through repeated monitoring of fibrinolytic activity of blood.

Streptkinase euglobulin lysis time (SK-ELT), fibrin and fibrinogen degradation products (FDP) and fibrinogen in blood were measured to determine the proper dosage of tAMCHA which would not cause ischemic complications but yet would suffice to prevent rebleeding in ruptured intracranial aneurysm. SK-ELT was almost doubled (130 sec) by the administration of 6-8 g/day of t-AMCHA within 24 h in normal control. On the other hand, SK-ELT in SAH patients fluctuated markedly during ten days after first bleeding. FDP demonstrated high value soon after first bleeding in Grade IV and V patients. Increase in FDP was also observed following rebleeding, severe vasospasm, and progressive neurological deterioration. Usually the increase in FDP was most obvious between 4-14 days after SAH. Fibrinogen showed the tendency to increase gradually by the administration of t-AMCHA, and this increased fibrinogen would be one of the alarm signs to indicate development of ischemic complications. From these results, it was suggested that doses of t-AMCHA should be determined precisely according to the result of repeated monitoring, and doses should be as such that it could keep SK-ELT constant between 130-150 sec.