Analysis of mortality of extradural haematoma in a general surgical unit

Evidence-based assessment of well-established interventions: the parachute and the epidural hematoma

BACKGROUND

The methods of evidence-based medicine are a relatively recent development in the understanding of clinical practice. They are criticized as not providing support for interventions long held to be highly effective based on experience that predated the availability of evidence-based analysis.

OBJECTIVE

To determine if the methods of evidence-based medicine can be successfully applied to interventions established before those methods were developed.

METHODS

Systematic review of English language literature on the natural history and treated prognosis of acute epidural hematoma and analysis of existing data on mortality associated with parachute use.

DATA SOURCES

Sources of data included Medline, Old Medline, Science Citation Index, British and US Parachute Associations, and Federal Aviation Administration and National Transportation Safety Board databases (both of the United States). Also included were national databases reporting mortality and total number of parachute uses.

RESULTS

The estimated mortality of falling from an airplane with an ineffective parachute is 74% (69-79). Mortality associated with effective parachute deployment is between 0.0011% and 0.0017%. For acute epidural hematoma, estimated mortality is 98.54% (95.1-99.9) without treatment and 12.9% (10.5-15.3) with treatment. The number needed to treat to prevent 1 death for the parachute is estimated to be 1.35 (1.27-1.45) and for epidural hematoma 1.17 (1.13-1.22) (95% binomial confidence intervals in parentheses).

CONCLUSION

The methods of evidence-based medicine are robust and can deal with interventions of great face validity and those considered well established before such methods were well developed. We propose initial criteria for evaluating the quality of evidence supporting long-established interventions.

Epidemiology of work-related traumatic brain injury: a systematic review

OBJECTIVE

This systematic review aimed to describe the burden and risk factors of work-related traumatic brain injury (wrTBI) and evaluate methodological quality of existing literature on wrTBI.

METHODS

A search of electronic databases (MEDLINE, EMBASE, PsycINFO, and CINAHL) was conducted to identify articles published between 1980 and 2013 using a combination of terms for work, TBI, and epidemiology, without geographical limitations.

RESULTS

Ninety-eight studies were included in this review, of which 24 specifically focused on wrTBI. In general, male workers, those in the youngest and oldest age groups, and those working in the primary (e.g., agriculture, forestry, mining) or construction industries were more likely to sustain wrTBI, with falls being the most common mechanism of injury.

CONCLUSIONS

This review identified workers at highest risk of wrTBI, with implications for prevention efforts. Future research of better methodological quality is needed to provide a more complete picture of the epidemiology of wrTBI.

The difference in the outcome of surgery for traumatic extradural hematoma between patients who are admitted directly to the neurosurgical unit and those referred from another hospital

In this study of 120 cases that had surgery for traumatic extradural hematoma (EDH) at Frenchay Hospital, England, between 1975 and 1987, the author attempts to outline the influence on the outcome of surgery for EDH of whether the patient is admitted directly to the neurosurgical unit or via another hospital. Only 15% of the patients were admitted directly, while 85% were referred. The results show that although the directly admitted patients included significantly more unconscious patients exhibiting clinical signs of herniation, their outcome was not significantly worse. Therefore, in support of previous reports, it is recommended that all head injured patients be admitted to the primary care of neurosurgeons.

Outcome after acute extradural haematoma, influence of additional injuries and neurological complications in the ICU

The purpose of this study was to evaluate the influence of additional, extracranial injuries and subsequent neurological complications in the intensive care unit on the functional outcome after head injury with extradural haematoma. The retrospective analysis included 139 adult patients with acute extradural haematomas admitted to the intensive care unit. Fifty-seven patients (41 per cent) were multiply injured (Injury Severity Score (ISS) = 36.5), and 82 (59 per cent) had a single head injury (ISS = 24.9). Fifty-four patients (39 per cent) developed neurological complications such as intracranial pressure (ICP) increase alone (N = 16), intracranial bleeding, ischaemic brain lesions or epileptic seizures with an associated ICP increase (N = 24) or without (N = 14). Overall, 77 per cent of the patients had a functional outcome (Glasgow outcome score 4 or 5); 46 per cent had a good recovery, 31 per cent were moderately disabled, 10 per cent were severely disabled, 4 per cent were persistently vegetative, and 9 per cent died. Differences were found between (1) patients with and without complications, (2) patients with extradural haematomas and patients with additional intracranial lesions, and (3) patients with a 'severe' Glasgow Coma Score (GCS) of 3-8 and patients with a GCS of 9-15. The presence of additional intracerebral injuries, and not extracerebral injuries, as well as the management of elevated ICP determines the final outcome in patients with extradural haematomas.

Extradural haemorrhage in infancy and childhood. A review of 35 years' experience in South Australia

One hundred and two paediatric cases of extradural haemorrhage (EDH) were treated in Adelaide, South Australia, during the period 1954-1988; 10 were infants (0-2 years) and 92 were children (2-14 years). There were 9 deaths (mortality 8.8%). Long-term disabilities severe enough to interfere with school and/or employment were seen in 8 (7.8%) survivors. This relatively low number of adverse outcomes is partly an expression of a low incidence (5.9%) of associated intradural haematomas and few high-velocity impacts due to vehicular accidents. There is reason to believe that the results of treatment have improved in the decade 1977-1988. We attribute this in part to early diagnosis by computed tomography (CT), but a contributory factor may be earlier referrals from country centres to a paediatric trauma centre and rapid transfer, by air or road, by medical retrieval teams.

Non-neurosurgical operative intervention in head-injured patients

Guidelines relating to non neurosurgical operative intervention in head-injured patients are not available for the British Isles. We present a series of seven patients with extradural haematoma operated upon in the referring hospital prior to transfer to our unit. The cases were analysed in an attempt to elucidate the efficacy of the emergency procedures and the associated problems. Recommendations are made in order to generate discussion on this aspect of head injury management.

Outcome prediction in extradural haematomas

Extradural haematoma (EDH) is generally a condition of young adult males. It represents only a small percentage of the total number of head injuries admitted to a neurosurgical service, but it must be differentiated from simple concussion, and this means that it is considered in a large number of patients. EDH has the potential for a low mortality rate because of its extraaxial location, but in practice it is approximately 10%. Our results show that about 40% of EDH present with vomiting or nausea and no focal neurological signs. Skull X-ray does not aid in the diagnosis as approximately 35% are reported as being normal. There is a place for conservative treatment of EDH but only if the shift of the midline is minimal (less than 5 mm). A score has been developed to predict accurately a patient's outcome after suffering an EDH. This score includes the Glasgow Coma Scale, pupillary reaction and initial CT scan appearance, and has an accuracy of 88%.

Experience with extradural haematomas in New South Wales

A retrospective study of 126 patients with extradural haematomas was made to determine whether their outcome could be modified by alteration of their management. Poor outcome occurred in those over 65 years of age, in motor smash victims, in those with fixed pupils, in those with major associated injuries or those comatose on hospital admission. The detection of skull fracture or of a lucid interval was not prognostically useful. A graduation in mortality according to the type of hospital was present but did not reach statistical significance. Failure to correct shock and delay in instituting definitive treatment were the major preventable factors which could be modified to improve outcome.