1. Paper reading 主持人 : 鄭淵家 醫師 報告人 :Intern 葉力仁

2. David H. Livingston, MD,* Robert F. Lavery, MA,* Marian R. Passannante, PhD,† Joan H. Skurnick, PhD,† Stephen Baker, MD,‡ Timothy C. Fabian, MD,§ Donald E. Fry, MD,i and Mark A. Malangoni, MD¶ From the Departments of *Surgery, †Preventive Medicine and Community Health, and ‡Radiology, New Jersey Medical School Newark, New Jersey, and the Departments of Surgery, the §University of Tennessee, Memphis, Tennessee, the iUniversity of New Mexico, Albuquerque, New Mexico, and ¶Case Western Reserve University, Cleveland, Ohio of Organs Dysfunctional Emergency Department Discharge of Patients With a Negative Cranial Computed Tomography Scan After Minimal Head Injury ANNALS OF SURGERY Vol. 232, No. 1, 126–132 © 2000 Lippincott Williams & Wilkins, Inc.

3. No other body system injuries CT: no intracerebral injury no intracerebral injury MHI No any neurologic finding Conclusions Discharge

4. MHI: Minimal Head Injury Or 2.evidence of posttraumatic amnesia + GCS:14-15 1. Documented loss of consciousness + GCS:14-15

5. Diagnostic studies have excluded intracranial injury Loss of consciousness Loss of consciousness MHI Background -- Standard practice for pts with head injury Hospital admission or prolonged observation ? 1. Undefined false- negative rate 2. Medicolegal considerations

6. How much is the false-negative rate Method 1. All patients > 16 years old 2. Blunt head trauma 3. Admitted to 4 lever 1 trauma centers 4. Prospective 5. Time: 22 months 6. Standardized NE 7. Noncontrast Cranial helical CT scanner

7. Definition of CT: Negative or Positive Positive: an intracranial injury was demonstrated. The need for intervention with a positive CT was determined by the neurosurgeons. Negative No intracranial injury was considered with or without extracranial injury Equivocal: when they could neither exclude nor determine the presence of an intracranial injury.

9. After the CT admitted and observed and the treatment of any other injuries. The standardized neurologic examination: –4 to 8 hours after arrival to the ED. –and 20 hours after admission –and at discharge for the outcomes: Outcomes: Neurologic deterioration, neurosurgical intervention, and death.

10. Deterioration decrease of >= 2 points GCS focal neurologic abnormality a loss of orientation to person or place the need to ICU due to head injury the need for any neurosurgical intervention. –endotracheal intubation –mechanical ventilation –use anticonvulsants –to treat cerebral edema, or intracranial pressure monitoring –craniotomy.

12. Sampling size Because the goal of this study was to 1.define a diagnostic evaluation 2.high negative predictive value (NPV) > 99.6% or more. 3.pts could be safely discharged from the ED Sample size: 2569

13. Data Analysis (1/2) To determine whether there were any center effects or significant practice pattern variations summaries of –demographic information –baseline clinical status –site-specific data surgical reports and clinical course of all patients who required neurosurgical intervention after a negative cranial CT were reviewed.

14. NPV true-negative results/(true-negative results + false-negative results). Lower 95% and 99% confidence limits were obtained for NPVs using the binomial probability distribution. This study was reviewed and approved by the institutional review boards at the four participating institutions. Data Analysis (2/2)

15. 2569 were enrolled 4568 4568 had signs of head trauma 6409 With blunt injury Excluded 1999 See table 1table 1 Excluded 417 See Table 2Table 22152 were studied Results(1/3)

16. Table 1

17. Table 2

18. Results (2/3) Clinically unimportant differences were found in age, gender, and mechanism of injury between some of the sites Centers effects: demographic variables The mean Injury Severity Score for the entire population was 10.6 (95% CI 10.4 –10.9). There were no differences in Injury Severity Score between centers.

19. Table 4

20. Preliminary 的 CT 可不可信 ? 97 % Agreement

22. Conclusion 5 patients (0.3%) had missed injuries on the preliminary reading and required neurosurgical intervention. –2 : increase in neurologic monitoring, –2 :ICU admission and anticonvulsants 1: underwent a craniotomy. –All recovered without sequelae. The NPV of the cranial CT scan based on the preliminary interpretation was 99.70% An analysis using the intent-to-treat group did not alter these results. The NPV defined by the need for a craniotomy was 99.94%

23. Discussions The data presented here clearly indicate cranial CT scan is necessary for patients who sustained either an LOC or posttraumatic amnesia 2. Safe? 1. CT Necessary? patients with a cranial CT scan, shows no intracerebral injury and no other body system injuries or a persistence of any neurologic finding can safely be discharged from the ED

24. Thank you