Arteriopathic complications during treatment of subarachnoid hemorrhage with epsilon-aminocaproic acid

Ischaemic stroke following tranexamic acid in young patients carrying heterozygosity of MTHFR C677T

The objective of this study is to report a new manifestation of acute stroke following antifibrinolytic agent administration in young women carrying heterozygosity for methylene-tetrahydrofolate reductase (MTHFR) C677T. The study included two young women who developed an acute ischaemic stroke following three days of tranexamic acid administration for bleeding gynaecological disorders. Case 1, a 44-year-old woman, presented left hemiplegia, mild dysarthria and anosognosia. Brain magnetic resonance imaging showed right ischaemic fronto-temporal lesion due to subocclusion of the right middle cerebral artery. Case 2, a 49-year-old woman, developed aphasia and right hemiplegia. Neuroimaging showed left capsular and periventricular infarcts due to near occlusion of the left internal carotid artery. Thrombophilia screening, coagulation parameters, homocysteine testing, 12-lead electrocardiography, and transthoracic and transoesophageal echocardiography were unremarkable. Genetic assay showed that both patients carried heterozygosity for MTHFR C677T, in which cytosine (C) is replaced by thymidine (T) at base position 677. To our knowledge, this is the first report describing the association between genetic factors and the onset of stroke following antifibrinolytic drugs intake. These data suggest a synergic effect of plasminogen activator inhibitor and heterozygosity for MTHFR C677T on the pathogenetic mechanisms leading to ischaemic stroke in young people.

Evidence-based pharmacotherapy for cerebral vasospasm

INTRODUCTION

The vast amount of literature on the pharmaceutical treatment of cerebral vasospasm after aneurysmal subarachnoid hemorrhage remains daunting. Optimal treatment regimens for patients can be obscured by studies not statistically powered to draw evidenced-based conclusions.

METHODS

In this chapter, we reviewed the English literature using the National Library of Medicine for studies regarding pharmacotherapies for the treatment of cerebral vasospasm. These studies were then categorized according to the US Preventative Services Task Force ranking system for evidence based medicine and reviewed each pharmacotherapy for its efficacy in the treatment of cerebral vasospasm.

RESULTS

Nimodipine (Nimotop), HMG Co-A reductase inhibitor (statins) and enoxaparin (Lovenox) were the only drugs with level-1 evidence available for the treatment of vasospasm from aneurysmal subarachnoid hemorrhage as defined by the US Preventative Services Task Force.

CONCLUSION

As the understanding of the pathophysiological mechanisms of vasospasm after aneurysmal subarachnoid hemorrhage evolves in the basic science laboratory, novel medications are being trialed in humans. However, significantly more work must be carried out in this area before we have an effective medical treatment that can prevent or reverse the devastating events of cerebral vasospasm.

A benefit-risk review of systemic haemostatic agents: part 1: in major surgery

Systemic haemostatic agents play an important role in the management of blood loss during major surgery where significant blood loss is likely and their use has increased in recent times as a consequence of demand for blood products outstripping supply and the risks associated with transfusions. Their main application is as prophylaxis to reduce bleeding in major surgery, including cardiac and orthopaedic surgery and orthotopic liver transplantation. Aprotinin has been the predominant agent used in this setting; of the other antifibrinolytic agents that have been studied, tranexamic acid is the most effective and epsilon-aminocaproic acid may also have a role. Eptacog alfa (recombinant factor VIIa) has also shown promise. Tranexamic acid, epsilon-aminocaproic acid and eptacog alfa are generally well tolerated; however, when considering the methods to reduce or prevent blood loss intra- and postoperatively, the benefits of these agents need to be weighed against the risk of adverse events. Recently, concerns have been raised about the safety of aprotinin after an association between increased renal dysfunction and mortality was shown in retrospective observational studies and an increase in all-cause mortality with aprotinin relative to tranexamic acid or epsilon-aminocaproic acid was seen after a pre-planned periodic analysis of the large BART (Blood conservation using Antifibrinolytics in a Randomized Trial) study. The latter finding resulted in the trial being halted, and aprotinin has subsequently been withdrawn from the market pending detailed analysis of efficacy and safety results from the study. Part 1 of this benefit-risk review examines the efficacy and adverse effect profiles of systemic haemostatic agents commonly used in surgery, and provides individual benefit-risk profiles that may assist clinicians in selecting appropriate pharmacological therapy in this setting.

Evaluation of Epsilon Amino-Caproic Acid (EACA) and Autologous Blood as Blood Conservation Strategies in Patients Undergoing Cardiac Surgery

BACKGROUND

To evaluate the effects of autologous blood and Epsilon amino-caproic acid on intra-operative and post-operative blood loss and homologous blood product requirements in patients undergoing cardiac surgery.

METHODS

Patients were randomly allocated to two groups of 30 each. In the Epsilon amino-caproic acid (EACA) group, the drug was administered in a loading dose of 100 mg/kg before skin incision followed by an infusion of 1/5 th the loading dose hourly and terminated 3 h after heparin neutralization. In the autologous transfusion (AT) group, 10% of the calculated whole blood volume was collected intra-operatively before cardiopulmonary bypass and re-infused after its termination.

RESULTS

Haemoglobin values were comparable pre-operatively, on cardiopulmonary bypass, off cardiopulmonary bypass and post-operatively on day two in both groups. Intra-operative blood loss was not significantly different (643.3+/-129.14 ml in group EACA versus 710+/-145.5 ml in group AT, p = 0.66). Although the chest drainage was more in group AT during 0-3 h (71.3+/-54.3 ml versus 112.6+/-79.3.6 ml, p = 0.006) it was comparable amongst in the first 24 h (231.1+/-98.3 ml in group AT versus 235+/-101.4 ml in group EACA, p = 0.88). Homologous blood product requirements were similar in both groups.

CONCLUSION

Autologous blood is as efficacious as Epsilon amino-caproic acid for blood conservation in cardiac surgery.

Reducing the risk of rebleeding before early aneurysm surgery: a possible role for antifibrinolytic therapy

Previous studies on the initial nonoperative management of aneurysmal subarachnoid hemorrhage (SAH) demonstrated that antifibrinolytic therapy reduced the risk of rebleeding by approximately 50%; however, prolonged antifibrinolytic treatment was associated with an increase in the incidence of hydrocephalus and delayed ischemic deficit. When early surgical intervention became routine for ruptured aneurysms, the use of antifibrinolytic therapy diminished. However, early surgery is generally performed in the first several days after SAH and the risk of rebleeding remains until the aneurysm is obliterated. Based on a review of the literature, the authors formed two hypotheses: 1) the high-dose intravenous administration of epsilon-aminocaproic acid (EACA), an antifibrinolytic agent, might reduce the risk of recurrent hemorrhage in the interval between SAH and early surgical intervention, and 2) a short course of EACA might not produce the increase in complications previously associated with its prolonged administration. The use of preoperative high-dose EACA therapy was evaluated in 307 patients to determine its safety and efficacy in reducing the incidence of rebleeding before early aneurysm surgery. All patients were admitted within 3 days of their SAH and were classified as Hunt and Hess Grades I to III. Only four patients (1.3%) suffered a recurrent hemorrhage. This compares favorably to the rebleeding rate of 5.7% reported for the early surgery group in the International Cooperative Study on the Timing of Aneurysm Surgery. The incidence of hydrocephalus or symptomatic vasospasm was not unduly elevated in patients receiving preoperative EACA. Thirty-five patients (11.4%) needed temporary cerebrospinal fluid drainage during their hospitalization and, overall, 8.8% required a ventriculoperitoneal shunt. The mean age of the patients who required a shunt was nearly 10 years older than the general study population. Seventy-one patients (23%) developed symptomatic vasospasm and 8.1% suffered a stroke. This study indicates that a brief course of high-dose EACA is safe and may be beneficial in diminishing the risk of rebleeding in good-grade patients prior to early surgical intervention. Further investigation is planned based on these promising results.

Prevention of postbypass bleeding with tranexamic acid and epsilon-aminocaproic acid

In this institution, two antifibrinolytic agents have been in routine use before cardiopulmonary bypass (CPB) to prevent bleeding due to fibrinolysis; epsilon-aminocaproic acid (EACA) or tranexamic acid (TA) are administered as intravenous infusions over 2 hours, from the time of anesthetic induction until the onset of CPB. TA is 10 times more potent and binds more strongly to plasminogen than EACA. Data were collected retrospectively on 411 patients undergoing first-time coronary artery bypass grafting with cardiopulmonary bypass who had received one of four therapy regimens: 10 g of EACA (65 patients), 15 g of EACA (60 patients), 6 g of TA (100 patients), or 10 g of TA (75 patients). Patients who did not receive any drug (91) served as controls. Anesthetic technique and the heparin/protamine protocol did not differ. Blood collected by mediastinal and pleural tubes was autotransfused up to 6 hours postoperatively. Both TA and EACA reduced post-CPB bleeding in the first 24 hours. Ten grams of TA was the most effective, resulting in a 52% and 36% reduction in blood loss over controls at 6 and 24 hours, respectively. Although 10 g of TA was more effective than 6 g of TA in blood loss control for the first 6 hours, the difference was not significant at 24 hours. A significantly lower number of patients in the 10 g TA group received blood products than in control (28% v 49%) patients (P = 0.02). Pretreatment with 10 g of TA prevented excessive (over 750 mL in 6 hours) bleeding after CPB.

Rebleeding, ischaemia and hydrocephalus following anti-fibrinolytic treatment for ruptured cerebral aneurysms: a retrospective clinical study

350 patients with subarachnoid haemorrhage from aneurysmal rupture--admitted in the years 1966-1983--were selected for a retrospective controlled study on the efficacy of antifibrinolytic therapy (AFT). Patients treated with antifibrinolytics were divided into two groups, according to the day of hospital admission and onset of therapy, respectively between 0 and 3 days (SG 1) and between 4 and 7 days from SAH (SG 2); treated patients (260 cases) received i.v. tranexamic acid (6 gr/day) for at least two weeks. Patients admitted before 1974, not receiving antifibrinolytics (90 cases), were selected as controls and divided into two groups (CG 1 and CG 2), according to the day of admission. In the first study group (admission 0-3 days) the rebleeding rate within 2 weeks was 9% versus 23% in controls (p less than 0.01). The incidence of rebleeding within 3 and 4 weeks was also significantly lower (p less than 0.05) than in controls. No significant difference was observed in the rebleeding rate in treated and untreated patients with late admission (4-7 days). Mortality from rebleeding was 16% in the first study group versus 17% in controls; in the second study group the figure was 6% versus 8% in controls. Seventy-five cases of ischaemic disorders (29%) were registered in treated patients versus 13 cases in controls (14%; p less than 0.01). Thirty-seven patients receiving AFT (14%) developed significant ventricular dilatation requiring shunt insertion, versus one patient in the control groups (1%; p less than 0.001). Final outcome was similar in the 4 groups. In conclusion--according to our data--AFT modifies the behaviour of rebleeding and the patients' course, although it does not modify the outcome after SAH. Clinical use of antifibrinolytic therapy appears still justified in those patients who cannot be operated on in the acute stage after SAH, provided that an associated anti-ischaemic therapy is undertaken.

Antifibrinolytic agents in subarachnoid haemorrhage

For many years clinicians have used antifibrinolytic agents to try to reduce rebleeding after subarachnoid haemorrhage. Early studies of their effectiveness produced conflicting results. This paper re-evaluates the available trials and considers benefits in the light of potential complications. Present evidence conclusively demonstrates that epsilon-aminocaproic acid and tranexamic acid administered in standard dosage, reduce the risk of rebleeding but, as a result of an increased incidence of ischaemic complications, do not benefit patients' outcome.

Spontaneous subarachnoid hemorrhage and negative cerebral panangiography. Review of 140 cases

One hundred and forty consecutive patients who sustained proven spontaneous subarachnoid hemorrhage (SAH) with negative cerebral panangiography were studied retrospectively. Attention was directed to the presence, amount, and distribution of subarachnoid blood on computerized tomography (CT) scans. It was determined that the finding of blood on CT had a significant association with clinical grade, loss of consciousness, ventricular ratio, fixed ischemic deficit, and total of all complications, but not with epilepsy, hypertension (previously known or detected on admission), treated hydrocephalus, rebleeding, angiographic spasm, and eventual outcome (which was generally excellent on follow-up examination). The distribution of blood, predominantly around the basal cisterns, suggests leakage from ventriculostriate and thalamoperforating vessels as the cause of SAH, and closer study of these vessels is suggested.

Cerebral vasospasm as a complication of aneurysmal subarachnoid hemorrhage: a brief review

Cerebral vasospasm is one of the most dreaded consequences of a ruptured intracranial aneurysm. Although exceptions may be found, the relationship between angiographic narrowing of cerebral arteries and deterioration of clinical status is supported by many authors. The cause of cerebral vasospasm still remains obscure. Several substances such as serotonin, prostaglandins, catecholamines appear to have a vasoconstrictive effect on the cerebral vessels. Recent evidence indicates that erythrocyte lysis within the subarachnoid spaces may play a major role in the genesis of delayed clinically relevant cerebral vasoconstriction following aneurysmal subarachnoid hemorrhage (SAH). The pathophysiology of brain ischemia following aneurysmal rupture, and the correlation between angiographic vasospasm, neurological condition, intracranial pressure (ICP) value, cerebral blood flow and CT findings are briefly discussed. It is concluded that, at present, blood volume expansion and/or induced hypertension, and pharmacological control of increased ICP provide the best basis for clinical management of the cerebral ischemic complications of SAH. Preoperative antifibrinolytic therapy and delayed surgical obliteration of the bleeding aneurysm, i.e. the policy at present most frequently adopted, are currently undergoing critical review in the light of the fact that antifibrinolytic therapy seems to be accompanied by a higher rate of ischemic SAH complications and vasospasm, whilst there are very recent suggestions that the results of early intracranial aneurysm surgery may be better than those of delayed surgery, if account is taken of the patients lost because of recurrent SAH or ischemia during the waiting period.

An experimental study of the influence of antifibrinolytic therapy on post-subarachnoid-hemorrhagic cerebral vasospasm and hydrocephalus

The incidence and severity of cerebral vasospasm and hydrocephalus following induced subarachnoid hemorrhage in an experimental group of animals that subsequently received epsilon-aminocaproic acid was compared to that seen in a control group that received no antifibrinolytic therapy. No augmentation of either vasospasm or hydrocephalus could be attributed to the epsilon-aminocaproic acid in the treated as compared to the control group.

Disseminated intravascular coagulation as a complication of ruptured intracranial aneurysms. Report of two cases

Two patients with recently ruptured intracranial aneurysms underwent surgical repair of these vascular lesions. Postoperatively, they showed clinical and laboratory evidence of disseminated intravascular coagulation (DIC). In both patients severe cerebral ischemic complications occurred. In one case the ischemic complications and the hematological changes were successfully reversed. This syndrome is a potential complication of aneurysmal subarachnoid hemorrhage (SAH), which requires prompt diagnosis and appropriate management. The relationship between hematological changes suggesting DIC and the ischemic complications of SAH should be extensively investigated.

The effects of epsilon aminocaproic acid on contractile properties and catecholamine content of rat carotid arteries

The prevalent use of epsilon aminocaproic acid (EACA) to prevent rebleeding in the preoperative management of ruptured intracranial aneurysms raises the question of a relationship between this drug and cerebral vasospasm. The effects of EACA on the contractile properties of the rat common carotid artery were measured in vitro, and the effects of EACA on the catecholamine content of these arteries were determined qualitatively. When carotid artery segments from rats that had been infused with lactated Ringer's solution alone were incubated in the presence of 1 mM EACA, they exhibited a decrease in contractile activity brought about by the presence of either serotonin or norepinephrine, and an increase in contractile activity when potassium chloride was used. These changes were not witnessed if the arterial segments came from rats that had been infused with lactated Ringer's solution containing EACA. No effect of epsilon aminocaproic acid was found on the median effective dose values for each vasoconstrictor used. Fluorescence histochemistry showed no qualitative changes in the catecholamine content of carotid arteries following EACA treatment.

Considerations in early surgery on good-risk patients with ruptured intracranial aneurysms

A retrospective analysis of 100 consecutive patients with proven ruptured intracranial aneurysms, classified as Botterell Grades I to III on admission, was carried out to evaluate the efficacy of early operation. Surgical and management mortality/morbidity rates were lower for cases in which a single hemorrhage was operated on within 48 hours than when surgery was delayed for 7 days or more. Surgical and management mortality/morbidity rates were worse in good-risk patients treated surgically between the 3rd and 7th days following a hemorrhage, reflecting the increased incidence of postoperative vasospasm and raised intracranial pressure encountered at surgery during this interval.

Spontaneous cure of ruptured intracranial arterial aneurysms

The case of a patient who had spontaneous cure of an intracranial saccular aneurysm, documented by angiography, is reported. This occurred in a 41-year-old patient, admitted four months after recurrent subarachnoid hemorrhage due to an angiographically verified supraclinoid internal carotid artery aneurysm. The relevant literature is reviewed, and the possible mechanism of spontaneous aneurysmal thrombosis is briefly discussed. It is concluded that repeating angiography is not without merit in patients with already documented cerebral aneurysms who are referred for surgical treatment some time after a subarachnoid hemorrhage.

The changing angiographic appearance of an arteriovenous malformation after subarachnoid hemorrhage

The changing angiographic appearance of a cerebral arteriovenous malformation (AVM) illustrated hemodynamic changes that can occur following subarachnoid hemorrhage and antifibrinolytic therapy. Decreased size of this lesion suggested thrombosis of the AVM. This appearance actually represented a transient, vasospastic phenomenon which reversed with time. Although the AVM underwent significant changes acutely, little changed in the long term.

Cerebral vasospasm in aneurysmal subarachnoid hemorrhage

Cerebral vasospasm is a major cause of morbidity and mortality following aneurysmal subarachnoid hemorrhage. With improvement in surgical techniques and perioperative care, the results in neurologically intact patients are generally satisfactory. However, cerebral vasospasm remains a major problem in the successful management of neurologically deteriorating patients. Until the pathophysiology of cerebral vasospasm is clarified, a reliable treatment regimen will remain elusive and the overall outlook for patients with aneurysmal subarachnoid hemorrhage will remain limited.

A method for monitoring antifibrinolytic therapy in patients with ruptured intracranial aneurysms

A rapid fluorometric assay technique has been utilized to assess the degree of fibrinolytic inhibition in 20 patients with ruptured intracranial aneurysms treated with epsilon-aminocaproic acid (EACA). This method quantitates the available plasminogen activity (APA) of plasma, and has proven to be a reliable means of monitoring antifibrinolytic therapy. Determination of the plasma APA also permits correlation of the level of fibrinolytic activity with putative complications of EACA therapy. Normal control plasma APA was 3.1 +/- 0.7 CTA units/ml, but in patients with subarachnoid hemorrhage (SAH), pretreatment fibrinolytic activity was supranormal at 3.78 +/- 0.88 CTA units/ml. During continuous intravenous administration of EACA (1.5 gm/hr) in patients with SAH, the plasma fibrinolytic activity was decreased to 0.9 +/- 0.31 CTA units/ml. A case described which examplifies the use of this assay. In addition, an approach to monitoring antifibrinolytic therapy using the plasma APA is proposed.

Myopathy due to epsilon amino-caproic acid

A subacute necrotizing myopathy developed in a patient treated with epsilon amino-caproic acid (EACA) for subarachnoid hemorrhage. The muscle biopsy showed features suggesting that the muscle fiber necrosis might have been due to capillary damage. An attempt to induce EACA myopathy in the rat was made, but no abnormality developed.

Preoperative treatment of ruptured intracranial aneurysms with tranexamic acid and monitoring of fibrinolytic activity

The fibrinolytic activity in cerebrospinal fluid has been monitored by determination of levels of fibrin split products (FSP) in 23 patients with ruptured intracranial aneurysms. In 20 of these 23, FSP was found in the cerebrospinal fluid (CSF), with levels ranging from 10 to 80 micrograms/ml. Eleven of the 23 patients were treated with 2 gm tranexamic acid daily. In these patients FSP was found in only two cases during the 2nd week, while in 12 untreated patients it was found in 10 cases. These results suggest that there exists a localized fibrinolytic activity, and monitoring the FSP levels in the CSF may be a simple and accurate method for controlling the efficiency of antifibrinolytic therapy. Thus, treatment could be begun with a lower dose, which could be increased later as deemed necessary from the results of careful monitoring.

Effect of antifibrinolytic therapy on subarachnoid fibrosis in dogs after experimental subarachnoid haemorrhage

The effect of antifibrinolytic therapy on posthaemorrhagic subarachnoid fibrosis was observed experimentally in dogs with the scanning electron microscope (SEM). The subchronic subjects, given intravenous injections of tranexamic acid (1 mg/day) for 12 days and sacrificed 3 weeks after cisternal blood injection, showed residual clot with thick fibrosis, especially around the haemorrhage. The chronic subjects, to which the same procedure was applied and which were sacrificed three months after cisternal blood injection, showed significant increases in the subarachnoid fibrosis, most remarkably in the parasagittal region. Tranexamic acid is widely used for preventing the recurrence of subarachnoid haemorrhage. However, it was revealed in this study that antifibrinolytic therapy might increase chronic posthaemorrhagic subarachnoid fibrosis, which is considered to be responsible for communicating hydrocephalus by disturbing epicortical CSF flow.

Prevention of recurrence of spontaneous subarachnoid haemorrhage by tranexamic acid

Tranexamic acid as an antifibrinolytic agent has been investigated in a controlled study in patients with recent subarachnoid haemorrhage. It is concluded that tranexamic acid improves neither rebleeding rates, nor mortality. Predominantly thrombotic complications have been noted as a more serious side effect of tranexamic acid.

Spontaneous thrombosis of ruptured intracranial aneurysms during treatment with tranexamic acid (AMCA). Report of three cases

Radiographically verified spontaneous disappearance of medium-sized arterial cerebral aneurysms is seldom reported, and only three times in connection with antifibrinolytic therapy (EACA). In our clinic repeat angiograms have shown non-filling of the aneurysms in three patients during treatment with tranexamic acid (AMCA) two, three, and four weeks respectively after primary bleeds. Initially, all three patients had severe radiological vasospasm associated with neurological deterioration. Follow-up angiograms have demonstrated partial reappearance of the aneurysm after one month in one patient and complete disappearance of the aneurysms in the other two patients after 9 and 22 months respectively. In two cases occlusion of cerebral arteries occurred. With regard to the higher risk of severe vasospasm and occlusion of cerebral arteries in our opinion it should not be a therapeutic goal to try to achieve a thrombosis of a ruptured aneurysm with antifibrinolytic drugs. The reason for spontaneous aneurysm thrombosis during treatment with AMCA may be a local inhibition of plasminogen activators in and around the aneurysm wall. It may also be related to the sympathomimetic property of the drug, with vasospasm and a subsequent flow-reduction inside the aneurysm or a possible interaction with other drugs and substances.

Recurrent subarachnoid hemorrhage associated with aminocaproic acid therapy and acute renal artery thrombosis. Case report

Epsilon aminocaproic acid (EACA) has been used to prevent rebleeding in patients with subarachnoid hemorrhage (SAH). Although this agent does decrease the frequency of rebleeding, several reports have described thrombotic complications of EACA therapy. These complications have included clinical deterioration and intracranial vascular thrombosis in patients with SAH, arteriolar and capillary fibrin thrombi in patients with fibrinolytic syndromes treated with EACA, or other thromboembolic phenomena. Since intravascular fibrin thrombi are often observed in patients with fibrinolytic disorders, EACA should not be implicated in the pathogenesis of fibrin thrombi in patients with disseminated intravascular coagulation or other "consumption coagulopathies." This report describes subtotal infarction of the kidney due to thrombosis of a normal renal artery. This occlusion occurred after EACA therapy in a patient with SAH and histopathological documentation of recurrent SAH. The corresponding clinical event was characterized by marked hypertension and abrupt neurological deterioration.

Prevention of early recurrence of spontaneous subarachnoid haemorrhage by epsilon-aminocaproic acid

A controlled clinical trial of epsilon-aminocaproic acid (E.A.C.A.), 36 g/day, was undertaken to assess its effectiveness in reducing immediate recurrence in patients with spontaneous subarachnoid haemorrhage (S.A.H.) proved by lumbar puncture. Of 83 patients treated with E.A.C.A., 3 (4%) had recurrent haemorrhage, and 1 (33%) of these died. Of 82 control patients who were not given any antifibrinolytic drug, 22 (26%) had recurrent haemorrhage, and 10 (45%) of these patients died. E.A.C.A. produced a striking reduction in the early recurrence of S.A.H. No serious side-effect resulted.

Myopathy associated with epsilon-aminocaproic acid (EACA) therapy. Report of two cases

The association of myopathy with epsilon-aminocaproic acid (EACA) treatment after subarachnoid hemorrhage in two cases is reported. Clinical and laboratory findings and possible mechanisms are discussed in light of the known pharmacology of the drug. Recovery ensues if EACA treatment is terminated as soon as myopathy appears.

Treatment of subarachnoid hemorrhage from ruptured intracranial aneurysm with tranexamic acid: a double-blind clinical trial

A double-blind clinical trial of tranexamic acid was carried out on 39 patients with fresh subarachnoid hemorrhage from a ruptured aneurysm. Twenty patients received tranexamic acid, 6 gm daily for 14 to 21 days, while 19 patients received conventional therapy of bedrest and dexamethasone when cerebral edema developed, plus isotonic saline. Rebleeding and mortality were reduced by one-fourth and one-fifth, respectively (p less than 0.001). No side-effects were observed. Tranexamic acid is valuable in the treatment of subarachnoid hemorrhage caused by ruptured intracranial aneurysms.

Use of epsilon aminocaproic acid (EACA) in the preoperative management of ruptured intracranial aneurysms

The authors report their experience with the use of epsilon aminocaproic acid (EACA) in the preoperative management of a series of patients with ruptured intracranial aneurysms. A similar series of patients was taken as control. They found that EACA is of definite value in preventing recurrent hemorrhage in the preoperative period. The significance of antifibrinolytic therapy in ruptured intracranial aneurysms is discussed.

Aminocaproic acid in the treatment of traumatic hyphema

Of 59 patients with traumatic hyphema studied prospectively, 32 received aminocaproic acid, an antifibrinolytic agent, to prevent secondary hemorrhage. The remaining 27 patients received placebo in an identical manner. Of the aminocaproic acid-treated patients, only one (3%) rebled, while nine patients (33%) receiving placebo suffered secondary hemorrhage. The results of this study indicate a statistically significant reduction (P less than .01) in the incidence of rebleeding in patients treated with this drug.

Intracranial aneurysms and subarachnoid hemorrhage. A cooperative study. Antifibrinolytic therapy in recent onset subarachnoid hemorrhage

In this cooperative study among 13 institutions, 502 patients were treated with antifibrinolytic medication (epsilon-aminocaproic acid or tranexamic acid) within a 14-day period following rupture of an intracranial aneurysm. Mortality at the end of 14 days was 11.6%; proved rebleed rate was 12.7%. Patients with an internal carotid or anterior cerebral aneurysm had the highest mortality and rebleed rate. Most rebleeds occurred between the sixth and eleventh days following the initial bleed. Significantly higher mortality was reported among patients with cerebral vasospasm, yet rebleed rate was no different among those patients with or without vasospasm. The same pattern was observed among patients with a mean blood pressure value above and below 110 mm Hg. We conclude that antifibrinolytic therapy provides beneficial treatment to patients with recent onset subarachnoid hemorrhage (SAH) following rupture of an intracranial aneurysm.