Disseminated intravascular coagulation as a consequence of cerebral damage

Contributing Factors for Coagulopathy in Traumatic Brain Injury

Context

In traumatic brain injury patients, coagulation disorder causes secondary brain injury, thereby increasing mortality and morbidity.

Aims

The aim of this study is to identify the factors responsible for coagulopathy in traumatic brain injury.

Settings and Design

This prospective longitudinal study from June 2012 included 100 patients with moderate and severe head injury presenting to National Institute of Neurological and Allied Sciences, Kathmandu, over 1-year period.

Subjects and Methods

Patients were evaluated for the development of coagulopathy, defined as collectively three abnormal hemostatic parameters, and associated risk factors for coagulopathy. They were then analyzed for correlation with coagulopathy.

Statistical Analysis Used

SPSS version 16 was used for the analysis of data. For identification of contributing factors, a stepwise logistic regression analysis was performed, including the factors with P < 0.05 from the analysis.

Results

Among the 100 patients, coagulopathy was present in 63% of cohort. Forty-three patients had severe head injury, and 76.7% (n = 33) of them had coagulopathy compared to 52.7% (n = 30) in 57 patients with moderate head injury (P = 0.013). Statistically significant correlation with coagulopathy was present with polytrauma, severity of head injury, blood transfusion, surgical intervention, and Marshall's classification of CT of the head; however, stepwise logistic regression analysis showed that blood transfusion, surgical intervention, polytrauma, and severity of head injury were significant independent variables responsible for the development of coagulopathy.

Conclusions

Traumatic brain injury is complicated with coagulopathy in up to 63% of patients. Blood transfusion, surgical intervention, polytrauma, and severity of head injury are significant independent variables responsible for coagulopathy.

Acute traumatic coagulopathy among major trauma patients in an urban tertiary hospital in sub Saharan Africa

BACKGROUND

Mortality from trauma remains a major public health issue as it is the leading cause of death in persons aged 5 to 44 years. Uncontrolled hemorrhage and coagulopathy is responsible for over 50% of all trauma related deaths within the first 48 hrs of admission. Coagulation profiles are not routinely done among trauma patients in resource limited settings and there is a paucity of data on acute traumatic coagulopathy (ATC) in sub Saharan Africa. The study was conducted to evaluate the prothrombin time and partial thromboplastin time (PT/PTT) as predictors of mortality and morbidity among major trauma patients.

METHODS

A prospective cohort study was carried out, in which major trauma patients admitted in A&E department between December 2011 to April 2012 were recruited. Five (5) mls of venous blood was drawn from a convenient vein within 10 minutes of the patient's arrival at A&E for analysis of PT/PTT. Patients were stratified into two groups by the presence/absence of coagulopathy then followed up for a 2 week period for morbidity and mortality.

RESULTS

A total of 182 major trauma patients were recruited; 149 (81.9%) were males, the mean age was 29.5 years (SD 9.8). Prevalence of coagulopathy was 54% (98/182). The mean ISS for the ATC group was 36.9 and the non ATC group was 26.9 (p=0.001). Patients with ATC stayed longer in hospital 11.24 days than non ATC patients 8 days (p=0.001). ATC was strongly associated with ARI (p= 0.003). Mortality was more in the ATC group 29 deaths compared to 9 deaths in the non ATC group. PTT was a strong independent predictor of mortality.

CONCLUSION

A significant proportion of major trauma patients were coagulopathic. Initial coagulation profile is useful in predicting outcomes for major trauma patients.

Role of coagulopathy in patients with head trauma

Coagulation disorders are a well known complication in patients with head injuries. A prospective study was undertaken to determine the incidence and prognostic value of haemostatic abnormalities in this group of patients. Clotting mechanisms in 105 patients with an isolated head injury were evaluated using platelet count (PC), prothrombin time (PT), activated partial thromboplastin time (APPT), thrombin clotting time (TCT), plasma fibrinogen concentration (Fib), level of fibrin-fibrinogen degradation products (FDP) and increased consumptive coagulopathy grade (ICCG) in the first 24 h after injury. The clinical severity of the head injuries was represented by the post-resuscitation Glasgow coma score (GCS) divided into four coma groups (CG). Test results were compared between two outcome groups of patients: discharged and dead. The incidence of disseminated intravascular coagulation (DIC) by laboratory criteria in the two groups was 12% and 38%, respectively. The differences between mean values of the discharged and dead patients for GCS, APTT, FDP and ICCG were statistically significant (P < 0.001). There was a very strong correlation between the GCS and values of the FDP, APTT, TCT and ICCG (P < 0.01). Stepwise logistic regression analysis demonstrated that GCS, FDP level, and ICCG predicted outcome in 84% of cases. Other tests did not provide additional predictive value. We conclude that evaluation of coagulation and fibrinolysis in patients with head injuries is not only important in identifying the occurrence of coagulopathy, but also useful in predicting head injury outcome.

Disseminated intravascular coagulation after isolated mild head injury

A rare case is described of acute disseminated intravascular coagulation (DIC) following isolated mild head injury with acute subdural haematoma, coagulopathy onset preceding craniotomy. Surgical treatment of the cause followed by swift diagnosis and treatment soon after surgery enabled a good outcome. Post-operative recollection of subdural and extadural blood was treated by further surgery. DIC following isolated mild head injury without axonal damage is rare, but fatal if missed. Thrombocytopaenia in head injured patients should be investigated expediently. Post-operative interim imaging (if not standard practice) should also be considered to exclude haemorrhagic recollection requiring further surgery.

Coagulation disorders after traumatic brain injury

BACKGROUND

Over the past decade new insights in our understanding of coagulation have identified the prominent role of tissue factor. The brain is rich in tissue factor, and injury to the brain may initiate disturbances in local and systemic coagulation. We aimed to review the current knowledge on the pathophysiology, incidence, nature, prognosis and treatment of coagulation disorders following traumatic brain injury (TBI).

METHODS

We performed a MEDLINE search from 1966 to April 2007 with various MESH headings, focusing on head trauma and coagulopathy. We identified 441 eligible English language studies. These were reviewed for relevance by two independent investigators. A meta-analysis was performed to calculate the frequencies of coagulopathy after TBI and to determine the association of coagulopathy and outcome, expressed as odds ratios.

RESULTS

Eighty-two studies were relevant for the purpose of this review. Meta-analysis of 34 studies reporting the frequencies of coagulopathy after TBI, showed an overall prevalence of 32.7%. The presence of coagulopathy after TBI was related both to mortality (OR 9.0; 95%CI: 7.3-11.6) and unfavourable outcome (OR 36.3; 95%CI: 18.7-70.5).

CONCLUSIONS

We conclude that coagulopathy following traumatic brain injury is an important independent risk factor related to prognosis. Routine determination of the coagulation status should therefore be performed in all patients with traumatic brain injury. These data may have important implications in patient management. Well-performed prospective clinical trials should be undertaken as a priority to determine the beneficial effects of early treatment of coagulopathy.

[Isolated acquired factor VII deficiency in patient with severe head trauma: use of factor VII (factor VII-LFB]

We report a case of transient acquired and isolated factor VII deficiency associated with severe head trauma. A 16-year-old boy was involved in a motor vehicle accident. CT scan showed frontal brain contusion and a cerebral haematoma (5 cm). First prothrombine time (PT) was normal. Rapidly, a severe coagulopathy developed, unresponsiving to fresh frozen plasma and vitamin K. Haemostatic markers analysis showed an isolated deficiency of factor VII at 15%. No inhibitory activity against factor VII could be detected. We successfully treated the deficiency with intermittent intravenous human factor VII (factor VII-LFB) during 10 days. Factor VII return to normal at 84%. Physiopathological and therapeutic aspects of this rare pathology are presented.

Association between intravascular microthrombosis and cerebral ischemia in traumatic brain injury

OBJECTIVE

To determine the association between traumatic cerebral ischemia and intravascular thrombosis, a common finding after traumatic brain injury (TBI).

METHODS

We reviewed samples of the frontal cortex and hippocampus from individuals who had sustained a fatal TBI. Sections stained with hematoxylin and eosin were reviewed and rated for severity of selective neuronal necrosis (SNN). Because intravascular fibrin microthrombi may lyse within a few days of TBI, we restricted our analysis to patients who had died within 48 hours of injury. Medical records in all cases were reviewed to rule out severe or prolonged hypotension or hypoxemia. Eleven patients with severe or global SNN were compared with 11 patients in whom SNN was mild or absent. Slides adjacent to the hematoxylin and eosin sections were stained with an immunofluorescent antibody to antithrombin III and were reviewed for intravascular microthrombosis. The number of microthrombi on each slide was counted by an investigator blinded to the hematoxylin and eosin findings, and density of intravascular microthrombi was calculated.

RESULTS

Intravascular microthrombi were noted in every section, excluding control (non-TBI) brain tissue. However, the density of microthrombi varied with the degree of SNN. We found a highly significant difference in the mean density of microthrombi between patients with severe SNN (7.74 +/- 3.7/cm(2)) and those with little or no SNN (2.58 +/- 1.0/cm(2)). Furthermore, a good correlation was noted between the location of intravascular microthrombi and that of SNN.

CONCLUSION

These data support a strong link between intravascular microthrombosis and neuronal death after brain trauma in humans and may have important implications for new therapeutic approaches.

Coagulation abnormalities following primary intracerebral hemorrhage

Systemic hemostatic activation following primary intracerebral hemorrhage (PICH) has been described, particularly with intraventricular or subarachnoid extension. Our objective was to study the occurrence of abnormalities of coagulation as measured by partial thromboplastin time, international normalized ratio, and platelet count in patients with PICH and no obvious cause for a pre-existing coagulopathy. Charts of PICH patients admitted between November 1991 and December 2001 were reviewed. We excluded patients with an underlying lesion, cranial trauma, anticoagulation, liver failure or sepsis. All patients had partial thromboplastin time, international normalized ratio, and platelet count measured on admission. An international normalized ratio > 1.4, partial thromboplastin time > 35, and platelet count < 100,000 were considered abnormal based on standardized values for our laboratory. All patients underwent a computed tomography (CT) scan on admission. Repeat CT was obtained for evidence of neurological deterioration. One hundred ninety-two patients with intracerebral hemorrhage were studied. Thirty-seven were excluded because of a possible underlying cause for a pre-existing coagulopathy. Thirteen of one hundred and fifty-five (8.4%) patients were found to have a coagulopathy based on our criteria. Three of thirteen (23%) patients with coagulopathy versus 3/142 (2%) without suffered neurological deterioration with evidence of hematoma enlargement (P = .008). Eleven of sixty-seven (17%) patients with intraventricular/subarachnoid extension versus 2/88 (2%) without had a coagulopathy (P = .002). Eight of thirteen (61%) patients with coagulopathy versus 29/142 (20%) without were dead at 30 days (P = .003). Coagulation abnormalities without an obvious etiology that may be consistent with low grade disseminated intravascular coagulation are seen in 8.4% of patients with PICH and are associated with extension into the subarachnoid and intraventricular compartments, neurological deterioration with hematoma expansion, and mortality at 30 days. This may represent a target for therapeutic intervention.

Early coagulopathy predicts mortality in trauma

BACKGROUND

Coagulopathy and hemorrhage are known contributors to trauma mortality; however, the actual relationship of prothrombin time (PT) and partial thromboplastin time (PTT) to mortality is unknown. Our objective was to measure the predictive value of the initial coagulopathy profile for trauma-related mortality.

METHODS

We reviewed prospectively collected data on trauma patients presenting to a Level I trauma center. A logistic regression analysis was performed of PT, PTT, platelet count, and confounders to determine whether coagulopathy is a predictor of all-cause mortality.

RESULTS

From a trauma registry cohort of 20103 patients, 14397 had complete disposition data for initial analysis and 7638 had complete data for all variables in the final analysis. The total cohort was 76.2% male, the mean age was 38 years (range, 1-108 years), and the median Injury Severity Score was 9. There were 1276 deaths (all-cause mortality, 8.9%). The prevalence of coagulopathy early in the postinjury period was substantial, with 28% of patients having an abnormal PT (2994 of 10790) and 8% of patients having an abnormal PTT (826 of 10453) on arrival at the trauma bay. In patients with disposition data and a normal PT, 489 of 7796 died, as compared with 579 of 2994 with an abnormal PT (6.3% vs. 19.3%; chi2 = 414.1, p < 0.001). Univariate analysis generated an odds ratio of 3.6 (95% confidence interval [CI], 3.15-4.08; p < 0.0001) for death with abnormal PT and 7.81 (95% CI, 6.65-9.17; p < 0.001) for deaths with an abnormal PTT. The PT and PTT remained independent predictors of mortality in a multiple regression model, whereas platelet count did not. The model also included the independent risk factors age, Injury Severity Score, scene and trauma-bay blood pressure, hematocrit, base deficit, and head injury. The model generated an adjusted odds ratio of 1.35 for PT (95% CI, 1.11-1.68; p < 0.001) and 4.26 for PTT (95% CI, 3.23-5.63; p < 0.001).

CONCLUSION

The incidence of coagulation abnormalities, early after trauma, is high and they are independent predictors of mortality even in the presence of other risk factors. An initial abnormal PT increases the adjusted odds of dying by 35% and an initial abnormal PTT increases the adjusted odds of dying by 326%.

Recombinant activated factor VII for cerebral injury-induced coagulopathy in pediatric patients. Report of three cases and review of the literature

Brain injury remains one of the leading causes of death and disability in children. Appropriate therapy involves aggressive management of intracranial pressure (ICP) and cerebral perfusion pressure, which often requires placement of an intraparenchymal ICP monitor or intraventricular catheter. These potentially life-saving interventions require normal coagulation function; however, several factors may lead to coagulopathy in the head-injured patient. Standard therapies, which often include multiple doses of fresh frozen plasma (FFP), have a number of drawbacks when used in the pediatric population. The use of FFP requires time to type and crossmatch, thaw, and administer. It imposes a significant volume load on a child in whom cerebral edema remains a problem. Success in using recombinant activated factor VII (rFVIIa) in the hemophiliac population suggests an alternative therapy. Three patients suffered severe coagulopathy after cerebral injury. One patient received rFVIIa after repeated doses of FFP had failed to correct the coagulopathy; the other two patients received rFVIIa as the initial therapy. Treatment with rFVIIa consisted of a bolus of 90 microg/kg. Recombinant activated factor VII rapidly corrected the patients' coagulopathies, which allowed placement of intraparenchymal fiberoptic lines and intraventricular catheters to monitor ICP. The patients suffered no complication from the placement of ICP monitoring devices, as demonstrated on computerized tomography scans obtained within 24 hours after placement. Brain injury-induced coagulopathy may lead to significant secondary injury and delays the invasive monitoring necessary for the aggressive management of intracranial hypertension. Fresh frozen plasma takes time to administer. may require repeated doses of significant volume for the pediatric patient, and may ultimately fail. Preliminary data indicated that rFVIIa provides a rapid and successful correction of coagulopathy in the head-injured patient.

Imaging of sequelae of head trauma

The imaging of head trauma has been one of the fundamental cornerstones of neuroradiology. As the practice of neuroimaging has matured, great strides have been made in the diagnostic as well as prognostic armamentarium available to physicians. Given the vast diversity of trauma mechanisms and clinical pathways, new advanced imaging technologies have had a lasting impact on the detection, description, and depiction of head trauma. Furthermore, these new tools are allowing the imaging specialist to function not only as an interpreter of what is seen but as a 21st century radiographic oracle. We present a comprehensive review of the imaging findings of sequlae of traumatic brain injury and the growing correlation of new neuroimaging techniques and neurotraumatic outcomes.

Coagulopathy predicts poor outcome following head injury in children less than 16 years of age

The authors examined the relationship between fibrin degradation products (FDP) and outcome in children with isolated head injury by reviewing the records of 69 children who met the following criteria: (1) less than 16 years of age; (2) diagnosis of isolated head injury and (3) FDP levels. Outcome was evaluated using the following Glasgow Outcome Scale (GOS): 1 = death; 2 = vegetative state; 3 = functionally impaired; 4 = minimal dysfunction; 5 = premorbid level of functioning. Poor outcome was defined as GOS 1-3. Twenty-nine of 33 patients with FDP > 1000 (g/mL had GOS scores < 4 compared to 4/36 patients (11%) with FDP < 1000 microg/mL (Fisher's Exact Probability Test P < .0001). When stratified by GCS, no other prognosticator of outcome was needed when GCS was < 7 and > 12. In patients with GCS 7-12, however, 4/6 with FDP >1000 microg/mL had a poor outcome and all 12 patients with FDP < 1000 microg/mL had a good outcome (P = .004). The authors conclude that FDP > 1000 microg/mL predicts poor outcome in children with isolated head injury. Fibrin degradation products are a strong independent prognosticator of outcome in children when GCS is between 7 and 12.

Delayed brain injury after head trauma: significance of coagulopathy

We reviewed the records of 253 patients with head injury who required serial computed tomographic (CT) scans; 123 (48.6%) developed delayed brain injury as evidenced by new or progressive lesions after a CT scan. An abnormality in the prothrombin time, partial thromboplastin time, or platelet count at admission was present in 55% of the patients who showed evidence of delayed injury, and only 9% of those whose subsequent CT scans were unchanged or improved from the time of admission (P less than 0.001). Among patients developing delayed injury, mean prothrombin time at admission was significantly longer (14.6 vs. 12.6 s, P less than 0.001) and partial thromboplastin time was significantly longer (36.9 vs. 29.2 s, P less than 0.001) than patients who did not have delayed injury. If coagulation studies at admission were normal, a patient with head injury had a 31% risk of developing delayed insults. This risk rose to almost 85% if at least one clotting test at admission was abnormal (P less than 0.001). We conclude that clotting studies at admission are of value in predicting the occurrence of delayed injury. If coagulopathy is discovered in the patient with head injury early follow-up CT scanning is advocated to discover progressive and new intracranial lesions that are likely to occur.

Coagulation changes after an experimental missile wound to the brain in the cat

Platelet studies (total number and platelet aggregation) and coagulation assays (fibrinogen, factor VIII, and anti-thrombin III) were performed on systemic arterial blood of four control and four experimental adult cats that sustained a penetrating missile injury to the brain. Among the brain-wounded, a significant decrease in the total number of platelets and aggregates occurred 120 minutes after injury. Fibrinogen levels decreased significantly in the brain-wounded animals by 240 minutes after injury and continued declining until the end of the 6-hour experiment. No significant changes occurred in factor VIII and antithrombin III levels in wounded as compared with control animals. These results indicate that blood coagulation factors are altered following a missile wound to the brain. These alterations may, occasionally, lead to clinically manifested bleeding disorders, specifically disseminated intravascular coagulation. Thus, early analysis and control of the coagulation system in the brain-wounded patient should be considered to prevent and treat bleeding disorders in the setting of penetrating head injury.

Early fresh frozen plasma prophylaxis of abnormal coagulation parameters in the severely head-injured patient is not effective

Serious head injury may be complicated by coagulation abnormalities. Fresh frozen plasma (FFP) has been advocated as resuscitation fluid, in patients with head injury, to prevent the development of abnormal coagulation. The efficacy of this practice has never been established. We retrospectively reviewed the records of 149 head-injured patients having a Glasgow Coma Scale of 9 or less. One hundred six received FFP and were without evidence of coagulopathies, while 42 received no FFP or had coagulopathies. Group 1 received FFP within a time from injury (T1) and group 2 received FFP after time (T2) or not at all. Groups were similar in demographics, injuries, presenting Glasgow Coma Scale, and presenting hematologic parameters in serial pretreatment or posttreatment hematologic parameters (P less than .05). There were no differences between patients receiving "early" FFP, as compared with those receiving FFP later or not at all. The time of FFP administration did not appear to be critical for effective prophylaxis against coagulopathy.

Association between necropsy evidence of disseminated intravascular coagulation and coagulation variables before death in patients in intensive care units

The necropsy findings in 21 patients on an intensive care unit, on whom coagulation studies had been performed immediately before death, were assessed. Eleven of the patients were retrospectively studied and 10 were reviewed consecutively in a prospective study. Fifteen patients (eight retrospective and seven prospective) had evidence of disseminated intravascular coagulation. Microthrombi were most often found in the lungs and kidneys. The most common abnormal coagulation tests in patients with necropsy evidence of disseminated intravascular coagulation were raised serum concentrations of fibrinogen and fibrin degradation products, prolonged prothrombin time, and reduced platelet counts. Reduced fibrinogen concentrations and a prolonged thrombin time were the least commonly observed abnormalities. There was no difference in either the prevalence or magnitude of abnormality of any particular coagulation variable test result between those patients with evidence of disseminated intravascular coagulation at necropsy and those without.

Coagulation disorders following acute head injury

Coagulation disorders following acute head injury were investigated in 100 patients: 81 patients survived and 19 patients died. Disseminated intravascular coagulation (DIC) was seen in 24%, and occurred most frequently in acute subdural haematoma, followed by contusional haematoma and contusion. Mortality rate of the patients with DIC was 58%. Level of serum fibrin-fibrinogen degradation product (FDP) was correlated with the amount of damaged tissue. The factors which influenced the prognosis for life were evaluated by multivariate analysis: in 100 patients, activated partial thromboplastin time (APTT) was most closely correlated with the prognosis for life, but in 24 patients with DIC, level of serum fibrinogen was most closely correlated with it.

Secondary intraventricular haemorrhage in blunt head trauma

Intraventricular haemorrhage (IVH) has been detected by computed tomography (CT) in 225 patients admitted to our clinic from 1977 to 1985. In 9 patients IVH was caused by trauma. We report two cases in whom IVH occurred after a lucid interval of about 10 hours postinjury. The pathogenesis of traumatic IVH is discussed comparing these cases with a review of the literature.

[Disseminated intravascular coagulation and subdural hematoma: a case report]

The authors present a case of acute subdural haematoma evacuated in the presence of a coagulopathy. Some elements necessary for the understanding of the etiopathogenesis of the disease are discussed.

Disseminated intravascular coagulation: a review

Disseminated intravascular coagulation (DIC) results from activation of the blood coagulation cascade by various disease processes. DIC may occur with blunt head trauma and, with severe head trauma, may reflect brain parenchymal injury. Oral and maxillofacial surgeons who treat traumatized patients should be aware of the implications of DIC with regard to patient management, diagnosis, and surgical considerations.

Disseminated intravascular coagulation fibrinolytic syndrome following head injury in children: frequency and prognostic implications

Eight-seven consecutive children with head injury were evaluated within two hours of injury by clinical examination, by computed tomographic brain images, and for systemic blood clotting disorders. All were treated by a standard regimen and survival rates calculated according to the initial neurologic abnormalities and pathology of the injury. Patients with the more severe neurologic abnormalities and those with more brain tissue destruction had poorer survival rates. However, 71% of all patients had one or more abnormal clotting tests and 32% had the disseminated intravascular coagulation and fibrinolysis syndrome by laboratory criteria. The mortality was over four times greater in those patients with DIC compared to those with normal clotting values. Our findings indicate that minor hemostatic abnormalities are the rule in head-injured children, that DIC occurs in nearly one-third of cases, and that DIC is associated with a marked increase in the mortality after brain injury: DIC may be a treatable secondary effect of head trauma that could decrease the mortality.

Disseminated intravascular coagulation as a complication of ventricular catheter placement. Case report

A child who developed generalized bleeding immediately after placement of a ventriculoperitoneal shunt was found to have evidence of disseminated intravascular coagulation (DIC). Infusion of fresh frozen plasma was followed promptly by improvement in laboratory values and cessation of bleeding. Complications of the acute bleeding episode included intraventricular hemorrhage, loss of 50% of the red cell volume into subcutaneous tissues, and transient peritoneal irritation. Defibrination syndrome (that is, DIC) due to release of tissue thromboplastin is a recognized complication of trauma, particularly with brain injury. Defibrination can be induced in experimental systems with administration of very small amounts of thromboplastin, which is present in high concentration in brain tissue. This has not been described previously with minor neurosurgical procedures. The diagnosis of DIC should be considered if excessive bleeding occurs after any brain insult, since early recognition and restoration of normal hemostasis by replacement of clotting factors should prevent major complications due to ongoing hemorrhage.

Intravascular coagulation: a common phenomenon in minor experimental head injury

Fibrin microthrombi were demonstrated by an immunoenzymehistochemical method in the small blood vessels of the lung and, to a lesser extent, in the brain in rats after minor experimental head injury. It was concluded that intravascular coagulation is a common phenomenon in head injury.

Afibrinogenemia and blunt head injury

A case is described of acute defibrination following blunt head injury in a patient with a Spitz-Holter drain. The cause of the disseminated intravascular coagulation is thought to be due to brain thromboplastins entering the systemic circulation through the Spitz-Holter drain, thus bypassing the blood-brain barrier.

Disseminated intravascular coagulation following cranial trauma. Case report

Cranial and spinal trauma resulted in disseminated intravascular coagulation (DIC) in a 78-year-old man, causing widespread bleeding and incoagulable blood. Traumatized brain tissue was found in the lumina of dural venous sinuses. The mechanisms of DIC are reviewed. It is suggested that intravascular release of potent cerebral thromboplastin contributed to the severity of DIC in this patient, by causing activation of the extrinsic clotting system. Intrasinus brain tissue in cases of human trauma has not previously been reported.

Disturbances of the coagulatory system in patients with severe cerebral trauma II. Platelet function

Platelet number, spontaneous aggregation, ADP- and adrenaline-induced aggregation, fibrinogen, and factors 2, 5, 7, and 10, were investigated in a series of 40 consecutive patients admitted to the clinic following severe head injury. Data were evaluated daily during the first week after trauma. Platelets were significantly decreased, particularly in non-survivors; there was no pathological spontaneous aggregation, except in a group of 22.5% of cases who had a mean age of 23.5 years. ADP-induced aggregation was negative in 69% of cases, and adrenaline-induced aggregation was absent in only two non-survivors. Fibrinogen was markedly reduced during the first five days, thereafter normalizing or increasing towards the end of the week. The other investigated values remained within their normal range of 70--130%. The results give no evidence of disseminated intravascular coagulation as a generalized and frequent phenomenon in severely head injured patients. There are, however, signs of latent consumption coagulopathy, which support data from the literature that indicate focal microthrombosis in contused brain areas.

Hydranencephaly in vertebral-basilar territory

A case is presented of almost complete destruction of the cerebellum secondary to a hemorrhagic event in utero. Lesions consistent with hydranencephaly were found in the territories of the vertebral-basilar circulation. Ependymitis and aqueduct occlusion secondary to the intraventricular bleeding resulted in intrauterine hydrocephalus formation.

Head injury and coagulation disorders

Coagulation studies (plasma fibrinogen, ethanol gelation test, and fibrin/fibrinogen degradation product concentration) were done in 150 patients who were admitted after blunt head injury. Results were abnormal in 60 patients and were found to be correlated with the level of consciousness and with the presence of neurological signs. Many of these patients had fractures, but findings in a control group of 26 patients with major fractures without head injury indicate that fractures were not of paramount importance in causing clotting changes. Conclusive evidence of disseminated intravascular coagulation was found in 12 patients. Cases with a fatal clinical course were mostly associated with very high fibrin/fibrinogen degradation product concentrations. Some case histories are reported, confirming the hypothesized correlation between coagulation results and brain tissue destruction rather than brain compression. It was concluded that some degree of disseminated intravascular coagulation in patients with blunt head injury occurs more often than expected and that coagulation studies might have both diagnostic and prognostic value.

Disturbances of the coagulatory system in patients with severe cerebral trauma. I

This is an investigation into thromboplastin time, partial thromboplastin time, plasma thrombin time, fibrinogen, and platelets in 30 patients with severe brain injury over 7--14 days. Platelets showed a very marked initial decrease and a slow return to normal around the seventh day. Fibrinogen was initially lowered in most of the cases, and raised from the second day onward. Changes in the other laboratory values were less definite. Latent signs of consumption coagulopathy were not accompanied by bleeding disorders, or by disseminated intravascular coagulation at autopsy. The severity of laboratory value changes clearly correlated with the extent of brain damage, and was significantly higher when the patient did not survive the first week after injury.

Cerebrovascular disease in sickle cell anemia: a clinical, pathological and radiological correlation

An opportunity to study cerebrovascular changes in sickle cell anemia (SCA) presented itself when a black child with this disorder died of bihemispheric strokes. Angiography demonstrated severe occlusive vascular disease involving primarily the circle of Willis and major bifurcations of both internal carotid arteries. Collateral circulation to the distal branches of the internal carotid arteries occurred through transdural anastomoses from the external carotid system and via the leptomeningeal route. Perfusion of the basal ganglia was accomplished by vessels arising from the proximal internal carotid arteries. These changes resembled those of Moyamoya disease. Autopsy showed old and recent cerebral infarcts. Two vascular processes were responsible for the arterial occlusions: (1) exuberant intimal hyperplasia, and (2) old and recent thrombi with partial recanalization. The former has been described only once before in SCA. Small vessels in the basal ganglia were exceptionally numerous and dilated. We conclude that intimal hyperplasia within large cerebral arteries may be responsible for infarction and small vessel prliferation in basal ganglia in patients with SCA.

Platelet aggregability in relation to impaired consciousness after head injury

ADP-induced platelet aggregation was studied for up to six weeks in 34 patients with head injuries. The patients were divided into three groups according to the degree of impaired consciousness assessed by a clinical coma scale, and change in platelet aggregation was related to the coma score. Platelet aggregation was markedly reduced in all eight patients dying within 24 hours of injury. All 17 patients who remained unconscious for four days or more showed decreased platelet aggregation up to nine days after admission, the most marked effect being on the second day. Platelet function in this group returned to normal within 16 days. Nine patients with only slightly impaired consciousness also showed subnormal platelet aggregation during the first few days with a return to normal by the fourth day. Platelet counts remained within normal limits in all groups. We suggest that during coma following head injury brainstem dysfunction induces neurohumoral changes in the blood which are responsible for a decrease in platelet function.

Disseminated intravascular coagulation and head injury

Blood coagulation tests were performed on admission to the hospital and on consecutive days after severe and moderate head injury in 34 patients. Platelet counts and fibrinogen were normal at admission and raised thereafter. The partial thromboplastin time was shortened at admission and lengthened in the following days. Fibrinolytic activity was enhanced at admission. The ethanol gelation test was negative in all patients during the post-traumatic time course. It was concluded that, in the first 24 hours after injury, activated coagulation was present after head injury. In contrast with data of other authors, disseminated intravascular coagulation did not occur in these series.