Factors determining uptake of diabetic retinopathy screening in Oxfordshire.

AIMS: To investigate variables at the demographic and primary care practice levels that influence the uptake of diabetic retinopathy screening. METHODS: Data were extracted from the management software of one screening programme for 21 797 people registered with 79 general practices. Uptake was examined by gender, age group, modality of screening (mobile unit at general practice versus high-street optometrist), and by general practice. A telephone survey of high-street optometrists provided information on the availability of screening appointments. RESULTS: Uptake was 82.4% during the study period, and was higher for men (83.2%) than for women (81.5%) (P = 0.001). Uptake varied by age group (P < 0.001), being lowest in those aged 12-39 years (67%). Uptake was higher for people invited to a general practice for screening by a mobile unit (83.5%) than for those invited for screening by a high-street optometrist (82%) (P = 0.006). After adjusting for these factors and for socio-economic deprivation score at the location of the general practice, heterogeneity in uptake rate was still observed between some practices. Our survey of optometrists indicated wide variation in the availability of time slots for screening during the week and of screening appointment provision. CONCLUSIONS: Diabetic retinopathy screening services do not achieve high uptake among the youngest or oldest age groups. Practices in the least deprived areas had the highest uptake. Variation in uptake between general practices after adjustment for individual-level variables and deprivation suggests that practice-level factors may have an important role in determining rates of screening attendance.

Updating diabetic retinopathy screening lists using automatic extraction from GP patient records.

OBJECTIVES: Diabetic Retinopathy screening services aim to reduce the risk of sight loss amongst patients with diabetes. The rising incidence of diabetes in England and the operational need to ensure the accuracy and timeliness of screening lists led to a pilot study of electronic extraction of data from primary care. This study aimed to evaluate the effectiveness of updating the single collated list of patients eligible for diabetic eye screening using extracts from electronic patient records in primary care. SETTING AND METHODS: The Gloucestershire Diabetic Eye Screening Programme (GDESP) provides screening for 85 General Practices in the county. Of these, 54 using Egton Medical Information Systems (EMIS) practice management system software agreed to participate in this study. The screening list held in 2009 by the Gloucestershire DESP of 14,209 patients known to have diabetes was audited against a list created with automatic extraction from General Practice records of patients marked with the diabetes Read Code C10. Those subsequently screened and referred to the Hospital Eye service were followed up. RESULTS: The Gloucestershire DESP manual list covering the 54 EMIS practices comprised 14,771 people with diabetes. The audit process identified an additional 709 (4.8%) patients coded C10, including 23 diagnosed more than 5 years ago, and 20 patients under the age of 20 who were diagnosed more than a year ago. CONCLUSION: Automatic extraction of data from General Practice identified 709 patients coded as having diabetes not previously known to the Gloucestershire DESP.

Mild hyperlactatemia in stable septic patients is due to impaired lactate clearance rather than overproduction.

A prospective study was conducted on 34 stable septic patients to determine whether mild hyperlactatemia is a marker of lactate overproduction or an indicator of lactate underutilization during sepsis. Plasma lactate clearance and lactate production were evaluated by modeling the lactate kinetic induced by an infusion of 1 mmol/kg L-lactate over 15 min. The patients were divided in two groups depending on their blood lactate: < or = 1.5 mmol/L (n = 20, lactate = 1.2+/-0.2 mmol/L) or > or = 2 mmol/L (n = 10, lactate = 2.6+/-0.6 mmol/L). The hyperlactatemic patients had a lower lactate clearance (473+/-102 ml/kg/h) than those with normal blood lactate (1,002+/-284 ml/kg/h, p < 0.001), whereas lactate production in the two groups was similar (1,194+/-230 and 1,181+/-325 micromol/kg/h, p = 0.90). A second analysis including all the patients confirmed that the blood lactate concentration was closely linked to the reciprocal of lactate clearance (r2 = 0.73, p < 0.001) but not to lactate production (r2 = 0.03, p = 0.29). We conclude that a mild hyperlactatemia occurring in a stable septic patient is mainly due to a defect in lactate utilization.

General practice on a new housing estate. 1956.

An analysis has been carried out of the records kept for the year 1953 by six doctors practising on a new housing estate near London. The population of the estate is described in terms of age, sex, and social class. 76 per cent. of the registered patients consulted a doctor at some time during the year, the consultation rate per person being 4.1 based on the average registered population; females had more consultations than males; 80 per cent. of all consultations were made by people under the age of 45. One-sixth of the patients accounted for about half of the consultations, and 30 per cent. of the consultations were made by the 7 per cent. of registered patients who consulted twelve or more times in the year. The consultation rates showed a slight, but statistically significant, social gradient, with more consultations among patients in the lower social classes. The illness rate was 26 per person, and was higher among males in infancy and old age, and among females between the ages of 5 and 64. A method of estimating the duration of sickness in terms of the period under medical care was employed. This showed that 70 per cent. of all illnesses were dealt with in single consultations, and that only 3 per cent. of illnesses were under care for more than 90 days. Over half of the practice population were under care for less than 5 days, and only 8 per cent. for more than 90 days. The proportion of patients having more than 30 days sickness generally increased with age, but there was a slight fall among the women aged 65 and over. Certificates were issued at the rate of about one for every five consultations, two-thirds of these being necessitated by the requirements of the National Insurance regulations. Prescriptions were issued at the rate of about one per consultation, the prescription rate being 41 per person. Only 5 per cent. of the practice population consulted the doctor but did not obtain a prescription. About 30 per cent. of the patients who consulted a doctor were referred outside the practices, 80 per cent. of all referrals being to hospitals, either as inpatients or as out-patients. The person-hospital referral rate was 20 per 100, and there were 31 referrals for every 100 registered patients. Males over 65 had the highest rates for consultations, illnesses, prescriptions, and referrals. The reason for this is discussed. The value of record-keeping by general practitioners is stressed, together with the need for a generally accepted method of expressing rates in studies of this kind.

Effect of sodium bicarbonate on intracellular pH under different buffering conditions.

Previous in vitro studies have reported a paradoxical exacerbation of intracellular acidosis following bicarbonate therapy due to the generated CO2 entering the cytoplasm. However, these studies were conducted in nonphysiological Hepes-buffered media. We compared the effect of a sodium bicarbonate load on the intracellular pH (pHi) of hepatocytes placed in nonbicarbonate (NBBS) or bicarbonate (BBS) buffering systems. The pHi of isolated rat hepatocytes was measured using the fluorescent pH sensitive dye BCECF and a single-cell imaging technique. Cells were placed in medium buffered with HCO3-/CO2 or Hepes. All media were adjusted to pH 7 with L-lactic acid or HCl. An acute 45 mM sodium bicarbonate load was added to each medium and the changes in pHi were measured every three seconds for 90 seconds. The sodium bicarbonate load caused rapid cytoplasmic acidification of cells in NBBS (N = 50, P < 0.001). In contrast, hepatocytes in BBS underwent a marked increase in pHi (N = 50, P < 0.001) without any initial decrease in pHi. These differences were highly significant for the buffer (P < 0.01), but not for the acid used. We conclude that sodium bicarbonate exacerbates intracellular acidosis only in a NBBS. Hence, in vitro studies reporting a paradoxical intracellular acidosis following bicarbonate therapy cannot be extrapolated to the in vivo buffering conditions, and should not be used to argue against bicarbonate therapy.

Effects of two volatile anesthetics (sevoflurane and halothane) on the hypothalamic noradrenaline release in rat brain.

There are marked increases in noradrenaline (NA) release during emergence from general anesthesia induced with volatile anesthestics. These changes in NA in the posterior hypothalamus of the rat were assessed by intracranial microdialysis. Sevoflurane and halothane in equipotent concentrations were used to obtain the same depth of anesthesia. NA release increased similarly with the two agents during recovery. However, NA release remained elevated longer with halothane, from which recovery was also slower.

[Transvascular fluid exchange disturbed by capillary injuries]. / Situations où les échanges liquidiens sont perturbs par des lésions capillaries.

Fluid exchange disorders due to capillary lesions are numerous and their extent depends on the underlying disease as well as the capillary structure of the affected organ. The inflammatory cascade, triggered by sepsis or reperfusion injury, is mediated by several humoral mediators and activated blood cells. These include pro-inflammatory cytokines, arachidonic acid, proteases, oxygen free radicals, polymorphonuclears, procoagulant, complement and fibrinolytic system. The interaction between these mediators leads to a loss of endothelial integrity, a loss of basment membrane and a disruption of the interstitial matrix, with wasting of the endothelial cytoskeleton. The alteration in permeability induces transcapillary exudation of water and protein in the interstitial space, leading to organ dysfunction, mainly the lungs and splanchnic organs. Nitric oxyde, by modulating the response of the endothelium to the cellular interaction may protect against capillary injury. Capillary "stress lesions" following microvascular hypertension are the physiological basis of neurogenic or high altitude pulmonary oedema, and overinflation injury from mechanical ventilation. The anatomic specific features of the cerebral capillaries resulted in the well known concept of blood brain barrier with it's changeing morphology. Under the effect of humoral mediators and cellular interactions, the endothelial cells are able, via a calcium-mediated mechanism, to contract and to modify capillary permeability, leading to vasogenic oedema.

Vigorous exercise in leisure-time: protection against coronary heart disease.

1138 first clinical episodes of coronary heart disease (CHD) in 17 944 middle-aged male office workers in the Civil Service are reported. Men who engaged in vigorous sports, keep-fit, and the like during an initial survey in 1968-70 had an incidence of CHD in the next 8 1/2 years somewhat less than half that of their colleagues who recorded no vigorous exercise. The CHD rates of men who took such vigorous exercise were lower in both fatal and non-fatal clinical manifestations, though more so in fatal; throughout the age-range studied, though more striking in later middle age and early old age; and in all other sub-groups examined, including men with a family history of CHD, the obese, the short of stature, cigarette smokers, and men with severe hypertension and subclinical angina, as well as in those in favourable situations for CHD or neutral. The generality of the advantage suggests that vigorous exercise is a natural defence of the body, with a protective effect on the ageing heart against ischaemia and its consequences.

Vigorous exercise in leisure time and the death rate: a study of male civil servants.

In 1968-70, 17,944 middle-aged male executive grade civil servants in Great Britain provided a record of their leisure-time activities for two sample days and they have been followed until the end of 1977. In a 20% sample (3591 men), 268 have died. Men who had reported "vigorous exercise" (VE) during the two days suffered fewer deaths from coronary heart disease throughout the years 1968-77; there was no significant difference in mortality from other causes. VE men recorded more physical activity in general, and they saw themselves as physically more active than the rest. Total physical activity scores, however, were weakly related to coronary mortality. Men reporting vigorous exercise smoked somewhat less than other men, but the two factors were independently associated with mortality from coronary heart disease.