Benefits of perfusion MR imaging relative to diffusion MR imaging in the diagnosis and treatment of hyperacute stroke

BACKGROUND AND PURPOSE: The development of thrombolytic agents for use with compromised cerebral blood flow has made it critical to quickly identify those patients to best treat. We hypothesized that combined diffusion and perfusion MR imaging adds vital diagnostic value for patients for whom the greatest potential benefits exist and far exceeds the diagnostic value of diffusion MR imaging alone. METHODS: The cases of patients with neurologic symptoms of acute ischemic stroke who underwent ultra-fast emergent MR imaging within 6 hours were reviewed. In all cases, automatic processing yielded isotropic diffusion images and perfusion time-to-peak maps. Images with large vessel distribution ischemia and with mismatched perfusion abnormalities were correlated with patient records. All follow-up images were reviewed and compared with outcomes resulting from hyperacute therapies. RESULTS: For 16 (26%) of 62 patients, hypoperfusion was the best MR imaging evidence of disease distribution, and for 15 of the 16, hypoperfusion (not abnormal diffusion) comprised the only imaging evidence for disease involving large vessels. For seven patients, diffusion imaging findings were entirely normal, and for nine, diffusion imaging delineated abnormal signal in either small vessel distributions or in a notably smaller cortical branch in one case. In all cases, perfusion maps were predictive of eventual lesions, as confirmed by angiography, CT, or subsequent MR imaging. CONCLUSION: If only diffusion MR imaging is used in assessing patients with hyperacute stroke, nearly one quarter of the cases may be incorrectly categorized with respect to the distribution of ischemic at-risk tissue. Addition of perfusion information further enables better categorizing of vascular distribution to allow the best selection among therapeutic options and to improve patient outcomes.     

蒽环类药对白血病及淋巴瘤患儿的心脏毒性

蒽环类药对白血病及淋巴瘤患儿的心脏毒性翟力平吴吴长根马伴吟陈伟达蒽环类化疗药（包括阿霉素、柔红霉素）引起心脏毒性已经是众所周知，但由于在肿瘤治疗中的重要作用，至今尚无满意的药物可以替代。据认为对儿童心毒性更敏感。如何掌握儿童治疗与心毒性之间的关系，...     

A portable target controlled propofol infusion system

A portable target controlled infusion system for propofol has been developed based on a Psion hand-held microcomputer and the Ohmeda 9000 syringe pump. The system uses a pharmacokinetic model which describes the distribution and elimination of propofol to achieve and maintain any selected target blood concentration. Target blood concentrations of 1 g/ml, 3 g/ml and 5 g/ml were selected in laboratory trials and the cumulative volumes delivered by the Psion system each minute were compared with the theoretical output calculated by the pharmacokinetic model. The results obtained showed that the computer system delivered volumes which were always within 2% of the theoretical values. This system offers a convenient and simple method of maintaining anaesthesia using propofol.     

ON WHICH DAY IS PAIN WORST FOLLOWING ADULT TONSILLECTOMY?

SUMMARY Anecdotal evidence from several ENT departments suggests that pain following tonsillectomy is worst on the second and/or third days after surgery. This study tests this hypothesis. A pilot study with 19 subjects suggested this theory might well be true. A fuller study was then carried out on 91 subjects with standardised surgical and anaesthetic techniques, and standardised analgesia for five days postoperatively. Pain on the second and third postoperative days was compared with that eight hours after the operation and on the first, fourth and fifth postoperative days. No statistically significant difference was found. There is increasing pressure for early discharge from hospital after surgery. If pain following tonsillectomy is not going to become worse at home, this will tend to make early discharge more acceptable to patients.     

A comparison of frequency and sources of nursing job stress perceived by intensive care, hospice and medical-surgical nurses

This study compared the frequency and sources of nursing job stress perceived by 35 intensive care (ICU), 30 hospice and 73 medical-surgical nurses. Analysis of variance revealed no significant differences among the three groups of nurses on the overall frequency of job stress. Post-hoc Tukey tests demonstrated a significant difference in three stress subscales among the three groups. ICU and hospice nurses perceived significantly more stress than medical-surgical nurses related to death and dying; ICU and medical-surgical nurses perceived significantly more stress than hospice nurses related to floating; and medical-surgical nurses perceived significantly more stress than ICU and hospice nurses related to work-overload/staffing. Spearman-Rank Correlation revealed no significant correlations among the three groups in their rank-ordering of the eight stress subscales. Death and dying situations were the most stressful to ICU and hospice nurses, while work-overload/staffing situations were the most stressful to medical-surgical nurses. Results of the study, although not generalizable, have implications for nurse managers.