Measurement of pediatric illness severity using simple pretransport variables.

OBJECTIVE: To test the hypothesis that pretransport variables can predict in-hospital mortality that will correlate with major interventions and unplanned events during interfacility transport. METHODS: A cohort of children (n = 2,253) transported by a specialized pediatric team to a children's hospital were studied. At the time of referral, data collected included age (months), heart rate, systolic blood pressure, respiratory rate, retractions, stridor or wheezing, seizures, skin perfusion, oxygen requirement, and mental status. Using univariate and stepwise logistic regression, variables predictive of in-hospital mortality were selected from a training set (n = 1,111) and assigned integers based on their computed coefficients. Probability of in-hospital mortality was calculated using the total integer score and age. The risk of mortality derived from the training set was validated in the remaining patients (n = 1,142) by comparing the observed and predicted mortalities. Major interventions performed and unplanned events were determined for each of five predetermined mortality risk groups. RESULTS: Variables (integers) predicting in-hospital mortality included systolic blood pressure (11), respiratory rate (6), oxygen requirement (11), and altered mental status (11). Observed mortality was similar to predicted mortality in all risk categories for the validation sample. As risk of mortality increased, so did the performance of major interventions and the occurrence of unplanned events. CONCLUSION: Four pretransport variables predicted in-hospital mortality. Risk of mortality correlated with the incidence of major patient interventions, and the occurrence of unplanned events increased as well. This model might be useful in comparing different transport systems using severity-adjusted assessment of children requiring interfacility transport.

Opiate modulation of striatal dopamine and hippocampal norepinephrine release following morphine withdrawal.

When opiates are abruptly withdrawn after chronic treatment, increases in hippocampal noradrenergic function are observed which are accompanied by decreases in striatal dopamine release. The latter effects have to shown to persist for several weeks following the onset of opiate withdrawal. We examined the long-term effects of opiate withdrawal on 4-aminopyridine and potassium stimulated release of striatal dopamine and hippocampal norepinephrine. Tissue samples were obtained either from rats that had been exposed to opiate withdrawal following a seven day morphine infusion or sham treated control subjects. At 48 hours after the onset of withdrawal (cessation of morphine infusions), slices were loaded with [3H] neurotransmitter, washed extensively, and exposed to different drug treatments. 4-aminopyridine induced concentration related increases in striatal dopamine release, which was 36% calcium independent. Similar values for fractional release of striatal dopamine were obtained in morphine withdrawn and control subjects, for both potassium and 4-aminopyridine induced release. In addition, thresholds for 4-aminopyridine or potassium induced release of striatal dopamine did not differ between control and morphine withdrawn subjects. Treatment with 1.0 microM morphine sulfate potentiated potassium evoked release of norepinephrine to an equal extent in both morphine withdrawn and sham treated hippocampal tissue. Exposure to a threshold concentration of potassium (8.0 mM), stimulated increased release of hippocampal norepinephrine in a significantly greater fraction of tissue samples obtained from morphine withdrawn animals. Although these results do not support changes in striatal dopamine release following opiate withdrawal, opiate mechanisms appear to be important determinants of in vitro hippocampal norepinephrine release.

Intracranial arteriovenous malformations in childhood: presentation, management and outcome.

Cases of true intracranial arteriovenous malformations (AVMs) presenting over a 25 year period were reviewed in order to achieve a better understanding of the behaviour and management of AVMs in children. There were 69 cases, presenting with haemorrhage (78%), seizures (13%) cardiac failure (3%) and focal signs with or without headache (6%). It was less common to present under six years of age. CT scanning, where performed, always demonstrated an abnormality, but this was suggestive of an AVM in less than one third. By contrast, angiography defined the lesion in 82% of initial studies. 59 patients underwent a surgical procedure directed at their AVM or an associated haematoma. Total AVM excision was obtained in 65%, with none of these later rebleeding. Three patients presenting solely with seizures were not operated upon initially, but underwent successful resections of their lesions after later haemorrhages. There were 6 (9%) deaths in the series, with focal deficits in 52% of survivors at last follow up. In the operative group these figures were 3% and 51%, respectively. None of the eight patients operated upon prior to a clinical bleed suffered a new neurological deficit. The role of stereotactic radiosurgery, although not used in any of our cases, is discussed. We believe that our results support an aggressive surgical approach to childhood AVMs, regardless of presentation, given the significant risk of morbidity from a later bleed, and the lack of a clearly better outcome with expectant management or irradiation.

A retrospective analysis of pituitary apoplexy.

Thirty-seven patients with pituitary apoplexy were analyzed with an emphasis on clinical presentation and visual outcome. Their mean age was 56.6 years, with a male to female ratio of 2:1. Presenting symptoms included headache (95%), vomiting (69%), ocular paresis (78%), and reduction in visual fields (64%) or acuities (52%). Computed tomographic scanning correctly identified pituitary hemorrhage in only 46% of those scanned. Thirty-six patients underwent transsphenoidal decompression. By immunostaining criteria, null-cell adenomas were the most frequent tumor type (50%). Long-term steroid or thyroid hormone replacement therapy was necessary in 82% and 89% of patients, respectively. Long-term desmopressin therapy was required in 11%, and 64% of the male patients required testosterone replacement therapy. Surgery resulted in improvement in visual acuity deficits in 88%, visual field deficits in 95%, and ocular paresis in 100%. Analysis of the degree of improvement in preoperative visual deficits with the timing of the surgery demonstrated that those who underwent surgery within a week of apoplexy had significant recovery in their visual acuities. In the stable, conscious patient with residual vision in each eye, surgical decompression should be performed as soon as possible, because delays beyond 1 week may retard the return of visual function.

Enterogenous cyst of the cervical spinal canal.

A case of an enterogenous cyst of the cervical spinal canal in an 18 year old man is presented, high-lighting the radiological findings. A brief overview is given of these rare cysts, together with their clinical and radiological features and associations.

Cysticercosis producing various neurological presentations in a patient: case report.

We present an unusual case of neurocysticercosis supported by characteristic lesions on computed tomography and positive serum and CSF titres. The patient came to medical attention on various occasions over a decade with three clearly separate neurological presentations (acute psychosis, cerebral infarction, and hydrocephalus) before diagnosis was made.

Iatrogenic spinal subdural haematoma.

Spinal subdural haematoma is a rare condition, usually seen in association with lumbar puncture or a bleeding disorder. It carries a high morbidity and mortality, and successful treatment requires prompt surgical intervention. We present a case of mixed spinal subarachnoid and subdural haemorrhage complicating failed spinal anaesthesia combined with anti-coagulation in an elderly woman, together with a review of the literature.

Hemifacial spasm in an infant due to fourth ventricular ganglioglioma. Case report.

The case of an infant is reported in which hemifacial spasm due to a ganglioglioma of the fourth ventricle was relieved by surgery. Previously described causes of hemifacial spasm are summarized, and the relevance of this case to theories on the pathogenesis of the condition is discussed.

Lumbar disc prolapse on the contralateral side at the same level following discectomy.

Lumbar disc prolapse managed surgically is occasionally complicated by a recurrent ipsilateral prolapse of the residual disc material at the same level, but only rarely by prolapse on the contralateral side at that level. We present a case of the latter, successfully managed by a second microdiscectomy, and review the frequency of such cases in previous series.

Surgical treatment of pontomedullary cavernomas.

Direct treatment of brainstem cavernous haemangiomas (cavernomas) naturally represents a considerable surgical challenge due to the close proximity of vital structures. The results of such treatment have only rarely been described. We report our experience in the management of seven patients with cavernomas of the brainstem treated by microsurgical resection. All patients presented with neurological symptoms directly attributable to one or more episodes of brainstem haemorrhage. CT scan examination in all cases revealed either obvious haematoma or a focal region of high density within the pons or medulla; calcification in and around the lesion was detected in two patients. MRI scanning was performed in four of our cases and was strongly suggestive of the diagnosis of cavernoma with evidence of both recent and older haemorrhage as evidenced by haemosiderin deposits. Cerebral angiography failed to disclose abnormal vessels to the cavernoma in any instance, although interestingly a co-existent but separate cerebellar venous malformation was observed in two of our cases. Surgery was performed between 19 days and 3 months following the most recent haemorrhage. Microsurgical removal of both haematoma and underlying cavernoma was accomplished either via a median suboccipital or retromastoid craniectomy, with an appropriate incision being made into that part of the brainstem most directly overlaying the lesion. Significant improvement in neurological function has followed in all seven cases. Although the natural history of symptomatic cavernous haemangiomas is incompletely understood, the favourable results obtained in our patients suggest that total surgical removal is both practicable and relatively safe even in the case of those lesions situated within the brainstem.

Costs, commitment, and rewards: factors influencing the design and implementation of internal labor markets.

Much research on internal labor markets has been hampered by the failure to differentiate the wide variety of ILMs, by accounts of their determinants that too heavily emphasize isolated causal factors, by the lack of detailed material describing the economic and organizational dimensions of their design and implementation, and by the neglect of managerial perceptions of and motivations for constructing ILMs. This paper presents detailed case studies of three organizations that have constructed very different ILMs. Based on this material, a model of the determinants of ILMs is developed that centers around the concepts of costs, commitment, and rewards and that attempts to assess the interactions of effects of markets and hierarchies on ILMs. The model is built on the premise that the underlying imperatives typically held to affect ILMs are inevitably filtered through managerial beliefs and the constraints on managerial decision making. The implications of these findings for theory and research on ILMs are discussed.

Allelopathic influence ofSorghum bicolor on weeds during germination and early development of seedlings.

The allelopathic interaction between sorghum [Sorghum bicolor (L.) Moench] and 10 species of grass and broadleaf weeds was investigated. Germination of weed seeds was slightly inhibited or stimulated, depending on species, when incubated in closed Petri dishes with germinating sorghum. Subsequent radicle and hypocotyl or coleoptile elongation of weeds was significantly inhibited by the germinating sorghum. For weeds interplanted with sorghum and grown under greenhouse conditions. The inhibitory effect on some weed species was still evident after 2 months of growth. Significant differences were found in the dry matter per weed plant grown in pots in proximity to sorghum vs. weeds grown in monoculture. Aqueous leachates from pots planted with sorghum alone or from a system in which sorghum roots protruded into water had strong allelopathic activity. These results indicate that water-soluble allelochemicals are produced by germinating sorghum seeds and that production of these substances continues during seedling growth.

Mass spectrometric 13C/12C determinations to detect high fructose corn syrup in orange juice: collaborative study.

The 13C/12C ratios in orange juice are sufficiently uniform and different from those in high fructose corn syrup (HFCS) so that the addition of HFCS to orange juice can be detected. HFCS averages -9.7% (parts per thousand) delta 13C, orange juice averages -24.5%, and mixtures of HFCS and orange juice possess intermediate values. One pure orange juice and 4 orange juice -HFCS mixtures containing from 25 to 70% orange juice were properly classified by 7 collaborators. Samples with delta 13C values less negative than -22.1%, 4 standard deviations from the mean of pure juices, can, with a high degree of confidence, be classified as adulterated. Samples with values more negative than -22.1% must be considered unadulterated with HFCS, because pure orange juices possess a range of delta 13C values. The 13C/12C mass spectrometric method was adopted official first action for detecting HFCS in orange juice.

Disappearance of patulin during alcoholic fermentation of apple juice.

Eight yeast strains were used in three typical American processes to ferment apple juice containing 15 mg of added patulin per liter. Patulin was reduced to less than the minimum detectable level of 50 microgram/liter in all but two cases; in all cases, the level of patulin was reduced by over 99% during alcoholic fermentation. In unfermented samples of apple juice, the concentration of added patulin declined by only 10% when the juice was held for 2 weeks, a period equivalent to the time required for fermentation.