Correspondence
Management of Head Injury
N Engl J Med 1993; 328:1124-1126April 15, 1993
- Article
To the Editor:
Drs. White and Likavec have provided a useful review of the management of head injury (Nov. 19 issue),1 but I was startled to read their advice that “aside from truly asymptomatic patients in the low-risk group, all should undergo CT [computed tomographic] scanning.” This strikes me as the kind of advice issued by specialists who deal with a selected subgroup of patients with head injuries. As a specialist in emergency medicine, I see a daily procession of patients with head injuries, very few of whom are completely asymptomatic. Careful history-taking often yields unclear information, which makes it difficult to categorize patients into the various risk groups. Alcohol-intoxicated patients are numerous and often present repeatedly to the same emergency department with minor head wounds. Should such patients have a CT scan on each visit? Other problems abound. Many hospitals do not have in-house, 24-hour-a-day CT coverage. The escalating use of CT in emergency medicine may strain an institution's resources, with a certificate of need necessary to acquire a second scanner. The cost-benefit ratio is not clear; what yield is expected from scanning the many low-risk patients who have some symptoms?
1 ReferencesJane O'Shaughnessy, M.D.
St. Vincent's Medical Center of Richmond, Staten Island, NY 103101
White RJ ,Likavec MJ . The diagnosis and initial management of head injury. N Engl J Med 1992;327:1507-1511
Full Text | Web of Science | Medline
To the Editor:
In their article on the management of head injury, White and Likavec recommend CT scanning for all patients in the moderate-risk group. Although I am aware of data to support their view, especially those of Stein and Ross,1 I think there is still some controversy. In children with normal examinations and only brief loss of consciousness (Rosenthal and Bergman define brief as a period of less than five minutes2; I would define it as a period of less than one minute), a skull x-ray film may be an appropriate method of screening.
In any urban emergency department, there is uncertainty about loss of consciousness in many patients who present after falls or altercations, with minor face and scalp contusions, lacerations of unclear mechanism, and slightly abnormal mental status after admitted alcohol and drug use. Often, emergency medical personnel believe there may have been an undocumented or brief loss of consciousness. The cost and risk of CT scanning are substantial; many such patients would require sedation or intubation and paralysis in order to undergo it. Is it not reasonable to observe such patients over a period of three to four hours and then discharge them if sequential neurologic examinations remain normal and mild abnormalities of mental status consistent with alcohol or drug use rapidly disappear?
2 ReferencesA.J. Smally, M.D.
Hartford Hospital, Hartford, CT 061151
Stein SC ,Ross SE . The value of computed tomographic scans in patients with low-risk head injuries. Neurosurgery 1990;26:638-640
CrossRef | Web of Science | Medline2
Rosenthal BW ,Bergman I . Intracranial injury after moderate head trauma in children. J Pediatr 1989;115:346-350
CrossRef | Web of Science | Medline
To the Editor:
. . . Hyperventilation, as a means of reducing intracranial pressure, has never been shown to improve the clinical outcome in patients with severe head injuries. In fact, the only randomized clinical trial on this subject demonstrated that, as compared with controls, significantly fewer patients who underwent hyperventilation had favorable outcomes at 3 to 6 months, although the differences were negligible at 12 months1.
The threat of inducing cerebral ischemia is of primary concern in the use of hyperventilation2,3. For this reason, we disagree with a statement made by White and Likavec: “Even with the ability to measure intracranial pressure, inducing hyperventilation may be crucial to improving intracranial pressure during the emergency room period.” Unless intracranial pressure is measured, there is no way of knowing whether a patient has intracranial hypertension, and there is no objective indication for the modification or end point of therapy. Blind hyperventilation exposes patients, especially those without intracranial hypertension, to unnecessary risks.
We monitor intracranial pressure in all patients with severe head injuries with intraventricular catheters, which are more accurate than the subdural monitors advocated by White and Likavec. In contrast to these authors, we have never observed ventricular collapse with displacement, nor do we have knowledge of such incidents from other physicians. Intraventricular catheters have the advantage of allowing drainage of cerebrospinal fluid to reduce intracranial pressure, a treatment that imposes no risk of cerebral ischemia, unlike hyperventilation or hypovolemia precipitated by the administration of mannitol.
Our patients are treated for intracranial hypertension by a stepwise approach, with cerebrospinal fluid drainage as the primary therapy4. We limit the use of hyperventilation to the acute setting of impending herniation, when cerebrospinal fluid drainage and other therapies -- mannitol and sedation -- have failed.
4 ReferencesKatrina Schreiber, B.A.
Andrew D. Firlik, B.A.
Robert J. Hariri, M.D., Ph.D.
Jamshid B.G. Ghajar, M.D., Ph.D.
Cornell University Medical College, New York, NY 100211
Muizelaar JP ,Marmarou A ,Ward JD , et al. Adverse effects of prolonged hyperventilation in patients with severe head injury: a randomized clinical trial. J Neurosurg 1991;75:731-739
CrossRef | Web of Science | Medline2
Sheinberg M ,Kanter MJ ,Robertson CS ,Contant CF ,Narayan RK ,Grossman RG . Continuous monitoring of jugular venous oxygen saturation in head-injured patients. J Neurosurg 1992;76:212-217
CrossRef | Web of Science | Medline3
Cold GE . Does acute hyperventilation provoke cerebral oligaemia in comatose patients after acute head injury? Acta Neurochir (Wien) 1989;96:100-106
CrossRef | Web of Science | Medline4
Ghajar JBG ,Hariri RJ . Management of pediatric head injury. Pediatr Clin North Am 1992;39:1093-1125
Web of Science | Medline
To the Editor:
White and Likavec wrongly assert that in the resuscitation of brain-injured patients “hypertonic saline . . ., and Ringer's lactate are the fluids of choice until cross-matched whole blood is available.” Appropriate fluid management in neurosurgical patients maintains isovolemia, avoids the risk of reduced serum osmolarity (which causes brain edema) and (less importantly) oncotic pressure, and preserves oxygen-carrying capacity.
Hypertonic fluids (e.g., 3 percent saline) are effective for volume resuscitation and may reduce cerebral edema, intracranial-pressure elevation, or both1,2. Their use remains largely investigational, however, reflecting persistent uncertainty over the physiologic implications (i.e., effects on myocardial contractility and renal function) of the very high serum sodium concentrations that may result3. The administration of Ringer's lactate, which is not isotonic (273 mOsm per liter), leads to a reduction in serum osmolarity, which in turn increases brain edema4 and thus cannot be advocated. The use of isotonic crystalloid (e.g., normal saline) is preferable. Packed red cells should be transfused to carry oxygen; the transfusion of whole blood is unnecessary, and this option is usually unavailable, since component therapy has become the mainstay of blood-banking practice5. Finally, type-specific blood is 99.7 percent as safe as fully cross-matched blood, is usually available within 5 to 10 minutes of a patient's admission, and is therefore recommended for resuscitation5.
5 ReferencesGareth S. Kantor, M.B., Ch.B.
Toronto General Hospital, Toronto, ON M5G 2C4, Canada1
Vassar MJ ,Perry CA ,Gannaway WL ,Holcroft JW . 7.5% sodium chloride/ dextran for resuscitation of trauma patients undergoing helicopter transport. Arch Surg 1991;126:1065-1072
Web of Science | Medline2
Gunnar W ,Jonasson O ,Merlotti G ,Stone J ,Barrett J . Head injury and hemorrhagic shock: studies of the blood brain barrier and intracranial pressure after resuscitation with normal saline solution, 3% saline solution, and dextran-40. Surgery 1988;103:398-407
Web of Science | Medline3
Smerling A . Hypertonic saline in head trauma: a new recipe for drying and salting. J Neurosurg Anesthesiol 1992;4:1-3
CrossRef | Web of Science | Medline4
Zornow MH ,Todd MM ,Moore SS . The acute cerebral effects of changes in plasma osmolality and oncotic pressure. Anesthesiology 1987;67:936-941
CrossRef | Web of Science | Medline5
Pisciotto PT, ed. Blood transfusion therapy -- a physician's handbook. 3rd ed. Arlington, Va.: American Association of Blood Banks, 1989:1-105.
To the Editor:
We agree with White and Likavec that CT is the method of choice for the initial assessment of patients with severe head injuries. However, because of the relative insensitivity of CT in the detection of small and nonhemorrhagic lesions, there is a marked discrepancy in a number of patients between the severity of neurologic dysfunction and the degree and extent of visible brain damage1.
Magnetic resonance imaging (MRI) has proved superior to CT in the evaluation of most central nervous system disorders. However, the use of MRI in patients soon after trauma has occurred has been limited because monitoring and life-support equipment interfere with the magnetic field. These difficulties can be overcome by the use of specially adapted, nonferromagnetic devices for monitoring and artificial ventilation.
At our institution, the use of MRI has become routine in patients who require general anesthesia or intensive care monitoring and artificial ventilation. During the past four years, more than 500 patients, including 150 with severe head injuries, have been examined on a 1.5-T MRI unit, with a nonferromagnetic ventilator with a redesigned valve system functioning in close proximity to the patient, and an oscillotonometric and capnometric device placed outside the examination room and connected to the patient by thin plastic tubes2,3. All examinations were carried out without any complications. In cases of acute head injury, MRI was generally indicated when the severity of neurologic symptoms could not be sufficiently explained by CT and when increased intracranial pressure could be ruled out. As compared with CT,4 MRI was superior in all regions of the brain, especially in the upper brain stem, where it detected traumatic lesions in 91 percent of patients (CT, 45 percent), and the lower brain stem (MRI detected lesions in 58 percent of patients, all of which were missed by CT).
In our experience, MRI can be safely performed in most patients with severe head injuries even in the initial stage, provided that a dedicated team and special equipment are available. The improved information about the degree and extent of traumatic brain damage may aid in therapeutic decision making and in predicting the prognosis.
4 ReferencesGunther G. Birbamer, M.D.
Wolfgang Buchberger, M.D.
Franz T. Aichner, M.D.
University of Innsbruck, A 6020 Innsbruck, Austria1
Gentry LR ,Godersky JC ,Thompson B . MR imaging of head trauma: review of the distribution and radiopathologic features of traumatic lesions. AJR Am J Roentgenol 1988;150:663-672
Web of Science | Medline2
Birbamer G ,Luz G ,Felber S ,Kampfl A ,Innerhofer P ,Aichner F . Magnetic resonance imaging and anesthesia: experience in 120 patients with severe head injury. Intensiv Notfallbehandlung 1991;16:90-943
Aichner F ,Felber S ,Birbamer G ,Luz G ,Judmaier W ,Schmutzhard E . Magnetic resonance: a noninvasive approach to metabolism, circulation, and morphology in human brain death. Ann Neurol 1992;32:507-511
CrossRef | Web of Science | Medline4
Birbamer G ,Judmaier W ,Felber S ,Buchberger W ,Aichner F . Innsbruck coma scale. Lancet 1991;338:1537-1537
Web of Science
Author/Editor Response
The authors reply:
To the Editor: The very reasons that Dr. O'Shaughnessy gives to illustrate the difficulty of risk classification in patients with head injuries support the appropriateness of CT scanning. Although we appreciate Dr. Smally's thoroughness in providing a reference1 in support of our thesis of imaging the moderate-risk group, we are unable to share his concern regarding CT scanning in children or agree with his suggestion that a skull x-ray film “may be an appropriate method of screening.” The latter is of marginal diagnostic value unless a cranial fracture is suspected. In the patients he describes as having scalp lacerations and altered mental status associated with alcohol and drug use, emergency CT scanning is strongly recommended, even in the few patients who require sedation or intubation and paralysis to complete the study. His suggestion of placing patients with head injuries under observation for three to four hours seems almost idyllic in view of the environment of the contemporary, overcrowded, understaffed emergency facility. The recent literature1,2 not only supports our approach to CT imaging in the groups at low-to-moderate risk but also demonstrates that this strategy results in substantial savings.
Although we acknowledge the concern of Schreiber et al. about hyperventilation and the thoroughly discussed dangers of producing ischemic zones in the damaged brain with extremely low partial pressures of carbon dioxide ( ≤ 25 mm Hg), it must be emphasized that the induction of hypocapnia (by lowering the partial pressure of carbon dioxide to 26 to 28 mm Hg) remains the key to the initial management of increased intracranial pressure. Their reliance on ventricular pressure monitoring and drainage (popularized by Becker et al.3) for the management of cranial hypertension is laudable. After years of using emergency ventricular catheterization, however, we found it difficult to maintain a patent draining system in the acutely injured patient, because of ventricular displacement or collapse. The subdural location offers no therapeutic advantage but does provide adequate intracranial-pressure monitoring and allow easy, rapid placement.
Kantor raises a number of important issues in reference to appropriate fluid management in patients with brain injuries who require major intravascular replacement. This entire area remains controversial4. In general, we advise the implementation of the protocols for fluid and blood replacement in hemorrhagic shock recommended by the Committee on Trauma of the American College of Surgeons5.
Birbamer et al. are correct in insisting on the superiority of the anatomical and pathological resolutions of MRI over CT, and we compliment them on their development of patient support systems that are compatible with MRI. At present, CT scanning is more than adequate for the emergency imaging of the brain after trauma.
5 ReferencesRobert J. White, M.D., Ph.D.
Matt J. Likavec, M.D.
Case Western Reserve University at MetroHealth Medical Center, Cleveland, OH 441091
Stein SC ,Ross SE . The value of computed tomographic scans in patients with low-risk head injuries. Neurosurgery 1990;26:638-640
CrossRef | Web of Science | Medline2
Shackford SR ,Wald SL ,Ross SE , et al. The clinical utility of computed tomographic scanning and neurologic examination in the management of patients with minor head injuries. J Trauma 1992;33:385-394
CrossRef | Web of Science | Medline3
Becker DP ,Miller JD ,Ward JD ,Greenberg RP ,Young HF ,Sakalas R . The outcome from severe head injury with early diagnosis and intensive management. J Neurosurg 1977;47:491-502
CrossRef | Web of Science | Medline4
White RJ . Who's on first? -- The traumatologist versus the neurosurgeon. Surg Neurol 1983;19:391-391
CrossRef | Web of Science | Medline5
Shock. In: Committee on Trauma, American College of Surgeons. Advanced trauma life support program. Chicago: American College of Surgeons, 1989:57-73.
- Citing Articles (1)
Citing Articles
1
Agustin Avilés, Renaldo Guzmán, Serafin Delgado, M. Jesús Nambo, Edna L. García, José C. Díaz-Maqueo. (1996) Intensive brief chemotherapy with hematopoietic growth factors as hematological support and adjuvant radiotherapy improve the prognosis in aggressive malignant lymphoma. American Journal of Hematology 52:4, 275-280
CrossRef
