Letter: E-aminocaproic acid and subarachnoid haemorrhage

Benefits and risks of antifibrinolytic therapy in the management of ruptured intracranial aneurysms. A double-blind placebo-controlled study

One hundred patients with a verified subarachnoid haemorrhage were studied in a double blind, placebo-controlled trial at a single centre to determine the value and relative risks of tranexamic acid (TXA) in the management of ruptured intracranial aneurysms. The incidence of recurrent haemorrhage between active and placebo groups was identical (12%) and the mortality from recurrent haemorrhage was 7% and 5%, respectively. The overall incidence of cerebral infarction before surgery, at discharge and at 6 months follow-up was greater in the TXA group (27%) than in the control group (11%). Post-operative cerebral ischaemia was significantly more frequent in the active, 18 of 29 as compared to 6 of 32 patients, in the placebo group. In a fifth of the patients in whom cerebral blood flow was estimated there was a significant reduction of cerebral blood flow (CBF) on the side of the ruptured aneurysm in the TXA treated group. It is suggested that this may be the cause of the increased incidence of cerebral ischaemia in this group. There was no significant difference in the incidence of cerebral vasospasm, hydrocephalus, visual disturbances and gastrointestinal disturbances. More fatalities were encountered from ischaemia and recurrent haemorrhage in the TXA group but these differences did not reach statistical significance at the 5% level. Given that disability was due to either vasospasm or recurrent haemorrhage than a patient under TXA treatment was significantly more likely to have disability due to vasospasm (p less than 0.04); the reverse was true for the placebo patient (p less than 0.05).

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.

Antifibrinolytic treatment in subarachnoid haemorrhage: present state

Two randomised controlled clinical trials in patients with recently ruptured intracranial aneurysms were undertaken using tranexamic acid (AMCA) to prevent early recurrent bleeding. In our accumulated series of 105 patients 53 were given AMCA and 52 were controls. 13% of the AMCA-treated patients and 31% of the controls rebled. In patients treated with AMCA the recurrent bleeding took place later than the rebleeding in the control patients. Vasospasm and delayed cerebral ischaemic deficits were seen more frequently in patients treated with AMCA. Total mortality from rebleeding and cerebral ischaemia was 25% in AMCA-treated patients and 19% in the controls during the six weeks' observation time. Coagulation factors remained unaffected by the drug. Local fibrinolysis in the cerebrospinal fluid decreased after one week in patients treated with AMCA. After two weeks the fibrinolytic activity was similar in AMCA-treated patients and in the controls. After experimental subarachnoid haemorrhage in 90 rabbits, AMCA was found to suppress plasminogen activator activity, mainly in the leptomeninges. This occurred however only during the first few postbleeding days. Antifibrinolytic agents only appear to reduce the risk of recurrent bleeding during the first ten day period after the primary aneurysm rupture. However they also seem to produce delayed cerebral ischaemia in patients with subarachnoid haemorrhage. Synthetic antifibrinolytics evidently shift the incidence of rebleeding curve to the right but these drugs are probably of diminished value in the subsequent weeks of risk.

Comparative clinical trial of epsilon amino-caproic acid and tranexamic acid in the prevention of early recurrence of subarachnoid haemorrhage

A comparative controlled clinical trial of epsilon aminocaproic acid (EACA), 36 g/day and tranexamic acid (TEA), 6 g/day, was undertaken to assess their effectiveness in reducing early recurrence of subarachnoid haemorrhage (SAH). Of 90 patients treated with EACA recurrent haemorrhage was seen in 8% of these patients and 7% of the patients developed delayed ischaemic deficit. The total pre-operative mortality in EACA-group was 11%. Of 61 patients treated with TEA, 10% had recurrent haemorrhage and delayed ischaemic deficit occurred in 5% of the patients. The total pre-operative mortality in TEA-group was 11%. No difference was found between the effectiveness and side-effects of these drugs.

Anti-fibrinolytic treatment in the pre-operative management of subarachnoid haemorrhage caused by ruptured intracranial aneurysm

One hundred consecutive patients treated with epsilon aminocaproic acid 24 grams daily prior to surgery for ruptured intracranial aneurysms have been compared with the previous 100 patients managed similarly but without anti-fibrinolytic drugs. No other alterations in management were made and the two series are closely comparable in all other respects. Fewer episodes of recurrent haemorrhage and deaths from this cause occurred in the treated patients, but more cases of cerebral ischaemia occurred. Neither difference is statistically significant and overall more deaths occurred in the patients treated with antifibrinolytic drugs. The value of this method of treatment in the management of aneurysmal subarachnoid haemorrhage is questioned.

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.

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.

Antifibrinolytic therapy of subarachnoid hemorrhage by intrathecal administration of p-aminomethylbenzoic acid

In patients suffering from subarachnoid hemorrhage (SAH), intrathecal administration of p-aminomethylbenzoic acid (PAMBA) was found to produce hemostatically effective concentrations of the antifibrinolytic agent in the cerebrospinal fluid (CSF). The early clinical findings speak in favor of this mode of administration.