This paper explains the regression to the mean, multilevel models and Poisson regression. When a variable of the same subjects was measured twice "the regression to the mean" --a phenomenon in whi4ch a variable that is extreme on its first measurement will tend to be closer to the center of the distribution for a later measurement. The regression to the mean should be considered if a quantitative variable is measured at baseline and at the end of observation. When subjects with a high quantitative measure at baseline are selected and observed after an intervention, for example, the variable will decrease after the intervention even if the intervention by no means effective to the variable. The regression to the mean is caused by random measurement error. Analysis of covariance with a baseline variable as a covariate is recommended for the analysis of a variable measured at baseline and at the end of observation. Multilevel models are useful for analyzing data with repeated measures. When comparing the effectiveness of treatment quantitatively, for example, the difference in the variable between treatment methods, the overall rate of change in the variable over time, and the difference in the rate of change in the variable over time between the treatment methods can be estimated and statistically tested by applying multilevel models. The number of events is properly analyzed by Poisson regression, not by linear regression. Poisson regression can be applied to the analysis of rates of occurrence if data includes the number of events and observation time measured as person-time.

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Diffuse axonal injury (DAI) in the acute stage was clinically evaluated using magnetic resonace imaging (MRI), which is considered superior to computed tomography (CT) in detecting parenchymal brain lesions. MRI was disadvantagous, however, to patients suffering from acute severe head injury because of the long time required to construct imaging and unstable patient vital signs. We conducted MRI safely under a high magnetic field (1.5 tesla) in acute DAI by close observation and with nonmagnetic respirator and electrocardiographic monitoring. MRI was conducted in 95 patients diagnosed with DAI classified into mild (14), moderate (17) and severe (64) DAI by criteria established by Gennarelli (1986). In patients with mild or moderate DAI, CT revealed no lesion in the parenchymal area although MRI detected lesions in every case, mainly in cortical white matter or basal ganglia. In patients with severe DAI, CT revealed parenchymal lesions in 14 although MRI detected further lesions in cortical white matter, basal ganglia, corpus callosum and brainstem in every case. These results correspond well to the experimental model Gennarelli's. This study concluded that MRI was useful in assessing acute DAI patients.

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The practical triage for trauma victims is not organized in Japan yet. To identify the importance of field triage in the city of Yokohama, we studied the influence of undertriage on outcome in seriously blunt trauma victims referred to our advanced trauma center from April 1997 to March 1999. We studied the differences in outcome and inhospital clinical course between patients with an injury severity score (ISS) >15 sent directly from the scene (DT group: n=10) and through interhospital transfer (IT group: n=16). Those two groups showed no difference in age, gender, ISS, revised trauma score (RTS) or abbreviated injury scale (AIS) scores at each injury site. Patients in the IT group who required ICU support experienced relatively longer length (3.7±3.3 vs 9.0±11.2 days, p=0.09) and significantly detrimental outcome estimated as severe disability (SD) on the Glasgow Outcome Scale ((GR or MD)/SD: 8/2 vs 5/11, p=0.04). These results demonstrated that undertriage worsened patient outcome and clinical course. The problem in trauma care will be clarified by further study of undertriage. We should study all trauma incidents, hospital transfer, and outcome in our clinical area in cooperation with the Fire Bureau and establish triage tools as a form of medical control.

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Background and Purpose: Super-selective thrombolytic therapy (STT) has only been applied in patients with brain embolism associated with known abnormalities such as atrial fibrillation in Japan. The purpose of this study is to report our experience with this therapy for acute phase atherothrombotic brain ischemia (TBI) to prevent from infarction. We compare the results of our study in patients with TBI with those of the same treatment in patients with embolic brain ischemia (EBI). Methods: STT consisted of intraarterial delivery of urokinase (UK) as the thrombolytic agent to the site of occlusion in 21 patients (10 patients with TBI and 11 with EBI). The maximum dose of UK used was 240, 000 IU. Immediate or rescue percutaneous transluminal angioplasty (PTA) was subsequently performed when recanalization failed or post-STT stenosis was >90%. The rates of successful recanalization, improvement of symptoms, required PTA, and occurrence of acute bleeding, and the total dose of UK, were compared between the two groups. Results: STT resulted in successful recanalization in all patients of both groups. The proportions of patients showing improvement of symptoms, required PTA, and those who developed acute bleeding, and the average dose of UK, were 90 and 73%, 10 and 9%, 10 and 18%, 114, 000 and 131, 000 IU in TBI and EBI groups, respectively. There were no significance differences in the above parameters between the two groups. Conclusions: The results of our STT showed high rate of improvement for TBI as well as EBI. We believe this STT will be a rather safe and recommendable treatment for the acute phase of TBI, as the catheters are improving continuously.

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Brachial plexus injury often causes severe chronic upper limb pain that persists for a long time. We present 2 cases in which brachial plexus avulsion pain was managed by epidural block. Brachial plexus avulsion caused by motorbike accidents elicited severe abnormal sensations in the upper limbs, where there was complete loss of motor and sensory neurological functions. There was continuous burning and intermittent cutting pain such as causalgia in the forearm of 1 patient and an oppressive sensation such as extraction of the upper arm from the shoulder in the other patient. Continuous cervical epidural blocks were applied to both patients immediately, resulting in obvious reduction in the degree of acute pain and in the induction of chronic pain in the upper limbs. This suggests that application of cervical epidural block in the early phase is an effective therapy for patients suffering brachial plexus injury for inhibiting the chronic upper limb pain. Note that should notice application of satisfactory analgesia even in emergency cases should be as fast as possible if there is a possibility that trauma will lead to chronic pain.

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Several symptoms following acute suppression of thyroid function during antihyperthyroid therapy remain yet to be uniformly recognized. We present a case manifesting electrolyte disorder, psychosis, and cardiac arrest during antihyperthyroid therapy. A 46-year-old woman diagnosed with hyperthyroidism and treated with propylthiouracil and β-blocker for a month was admitted to another hospital reporting dyspnea. A few hours after admission, she suddenly underwent cardiac arrest. After immediate cardiopulmonary resuscitation, severe hypocalcemia and cardiomegaly were diagnosed. She was transferred to our emergency room due to her obscure clinical course and severe hypocalcemia. She also experienced hallucinations. Electrocardiography, echocardiography, and chest radiography showed no abnormalities. Calcium administration gradually lowered her serum calcium to within normal range on day 5 after admission. Her mental disturbance disappeared and thyroid function returned to normal. Her severe electrolyte disorder also improved after treatment. She was discharged from the hospital in good condition. Hypocalcemia following acute suppression of thyroid function has been recently recognized as “hungry bone syndrome.” Different psychiatric symptoms and cardiocirculatory disturbances are observed during antihyperthyroid treatment. As our case showes, the importance of intensive care for patients with hyperthyroidism cannot be overemphasized.

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