Modulation of platelet cytosolic calcium during erythropoietin therapy in uraemia

Erythropoietin therapy for uraemic anaemia is associated witha high rate of hypertensive and thrombotic complications. Themechanism is unknown, but a change in cellular calcium controlmay be relevant to changes in blood pressure and thrombosis. Platelets were utilized as a model of vascular smooth musclecells. The effects of erythropoietin therapy on platelet cellularcalcium, assessed by fura-2, were meas ured in 25 patients receivingrenal replacement therapy during a 6-month treatment period. Three patients failed to reach a target haemoglobin and wereexcluded from the analysis. Blood pressure increased in 11 ofthe remaining 22 subjects, eight requiring an increase in antihypertensivemedication. There were no differences in cellular calcium controlbetween the group in whom blood pressure rose and patients withstable blood pressure. Overall there was a fall of 24% in restingcytosolic calcium (baseline 69.2 ± 5.1 to 52.5 ±3.0 nmol/1, P<0.05) after 3 months of erythropoietin therapy.There was no change in the thrombin-stimulated peak responsein the presence of extracellular calcium during therapy, althoughthrombin-stimulated intracellular release also fell at 3 months(baseline 769±61 versus 3 months 559±49nmol/l,P<0.01 This study suggests that intracellular free calcium controlwithin platelets improves in response to erythropoietin therapy.However these changes appear not to be related to the developmentof hypertension.     

Neuropsychological sequelae of obstructive sleep apnea-hypopnea syndrome: a critical review.

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a well-recognized clinical sleep disorder that results in chronically fragmented sleep and recurrent hypoxemia. The primary daytime sequelae of the disorder include patient reports of excessive daytime sleepiness, depression, and attention and concentration problems. It has been well established that OSAHS negatively impacts certain aspects of cognitive functioning. The primary goals of this article are to (1) clarify the pattern of cognitive deficits that are specific to OSAHS; (2) identify the specific cognitive domains that improve with treatment; and (3) elucidate the possible mechanisms of cognitive dysfunction in OSAHS. At the conclusion of the paper, we propose a potential neurofunctional theory to account for the etiology of cognitive deficits in OSAHS. Thirty-seven peer-reviewed articles were selected for this review. In general, findings were equivocal for most cognitive domains. Treatment, however, was noted to improve attention/vigilance in most studies and consistently did not improve constructional abilities or psychomotor functioning. The results are discussed in the context of a neurofunctional theory for the effects of OSAHS on the brain.     

Socioeconomic status and outcome from intensive care in England and Wales

OBJECTIVE: The objective of this study was to estimate the association between socioeconomic status (SES) and outcome for admissions to intensive care. RESEARCH DESIGN: Retrospective cohort study. SUBJECTS: We studied 51,572 admissions to 99 intensive-care units in England and Wales between 1995 and 2000. MEASURES: The SES of admissions was measured using Carstairs deprivation scores. Outcome was hospital mortality after adjustment for case mix using the APACHE II method. RESULTS: Admissions of lower SES were, on average, younger and less likely to be following surgery. There was evidence of a SES gradient for hospital mortality in admissions after elective surgery after adjusting for case mix (test for trend P <0.001), with higher SES associated with lower mortality. In the least-deprived quintile of SES, the odds ratio for hospital mortality was 0.70 (95% confidence interval, 0.58-0.84) compared with the most deprived quintile. There was no evidence of a SES gradient for hospital mortality in nonsurgical or emergency surgical admissions, and the decision to withdraw active treatment did not differ by SES. CONCLUSIONS: There is a SES gradient for hospital mortality in elective surgical admissions that is not explained by differences in case mix or the withdrawal of active treatment. Further research is required to establish if this finding can be explained by unmeasured differences in health status at admission to an intensive-care unit or differences in care and to establish the potential impact these results may have on interpreting comparative surgical performance data.     

Management of minor head injuries in the accident and emergency department: the effect of an observation ward.

The management of 483 patients presenting with minor head injury to the accident and emergency (A&E) departments of two Scottish hospitals was studied prospectively. Such patients comprised 5.7 and 3.9% of the total attendances to each department. Of the 277 patients assessed in the former department, 83 (30%) fulfilled at least one of the currently accepted criteria for recommending admission to hospital and 49 (17.7%) patients were actually admitted. Patients in whom head injury was not the principal reason for admission were excluded from the study. In the same time period the second department dealt with 206 patients with minor head injury, 49 (24%) of whom had criteria for admission. However, significantly fewer, 10 (4.9%) patients, were actually admitted. The major relevant factor when comparing the two departments was the existence in the former of an observation ward. These results support the view that easy access to hospital beds is a major determinant of management in patients presenting with minor head injury to the A&E department and may be more influential than clinical findings.