On-call neurosurgery: can this continue as a free service?

Since 2005, Acute National Health Service (NHS) Trusts have been funded using a system called Payment by Results. This provides a national or regionally set tariff per patient treated, according to a health resource group code. Health resource group codes vary according to diagnosis or procedures carried out and patient co-morbidities. This only funds trusts admitting patients rather than those advising remotely, as neurosurgical centres do for the majority of emergency referrals. Numbers of referrals and emergency admissions to our unit were analysed for the last 4 years in addition to consultant and secretarial time devoted to these cases. This demonstrated an increase in the number of referrals and time spent advising. For the trust hosting the neurosurgical department, this represents a funding deficit for services offered. In our region, this has been remedied by charging neighbouring trusts a fee for emergency neurosurgical referral advice. However, this is difficult to administrate and would be better served as a service-level agreement with our commissioners. Only when this has been achieved, can neurosurgical centres provide a comprehensive consultant-led emergency service without it being to the detriment of the host trust.

Comparison of fluorogenic and chromogenic assay systems in the detection of Escherichia coli O157 by a novel polymyxin-based ELISA.

AIMS: Different indicator enzymes and fluorogenic or chromogenic substrates were compared as detector systems in a novel polymyxin-based enzyme-linked immunosorbent assay (ELISA) for Escherichia coli O157 lipopolysaccharide (LPS) antigens. METHODS AND RESULTS: An ELISA system was developed using polymyxin immobilized in the wells of a microtitre plate as a high-affinity adsorbent for E. coli O157 LPS antigens, which were immunoenzymatically detected using anti-E. coli O157 antibody-enzyme conjugates. With peroxidase as the indicator enzyme the fluorogenic substrates Amplex Red and QuantaBlu produced only slight improvement in the performance characteristics of the polymyxin-ELISA compared with the use of the chromogenic substrate tetramethylbenzidine (TMB). On the other hand, with alkaline phosphatase as the indicator enzyme a pronounced improvement in assay performance was noted using the fluorogenic substrate Attophos compared with the chromogenic substrate p-nitrophenylphosphate. CONCLUSIONS: The detection system exhibiting the best characteristics with respect to cost, ease of use and overall performance in the detection of E. coli O157 in enrichment cultures from a variety of solid foods was based on the use of peroxidase as the indicator enzyme with the chromogenic substrate TMB. SIGNIFICANCE AND IMPACT OF THE STUDY: The polymyxin-ELISA provides a rapid, simple and inexpensive assay system for the detection of E. coli O157 in foods.

Zig-zag bicoronal scalp incision for cranio-facial cases in paediatric neurosurgery.

TECHNIQUE: We present the use of a zig-zag bicoronal scalp incision for cranial-facial cases in paediatric neurosurgery. CONCLUSION: The authors believe that this technique leads to improved cosmesis, especially when the hair is wet.

Generic waiting lists for routine spinal surgery.

National Health Service Hospitals are under pressure to reduce waiting lists within the constraints of a limited infrastructure. We implemented two systems to reduce waiting times for elective non-complex spinal surgery. The first of these was the introduction of managed generic waiting lists for both initial outpatient appointments and subsequent surgery. Thereafter, the MRI booking system was integrated with outpatient review appointments. Times from referral to first outpatient appointment and from scan to outpatient review and time on waiting list for surgery were analysed before and after implementation of these changes. Despite constant unit capacity there was a global decrease in waiting times. Before introduction of the generic waiting list, 37% of listed patients waited for more than 9 months; this figure fell to zero. Time from scan to outpatient review was 185 days before integration, 30 days after. Changes of this sort demand a quorum of consultants who will accept each others' recommendations. The generic waiting list will have impact only when there are large disparities in waiting times for different consultants. Targets are met at the expense of continuity of care.

Successful treatment of aspergillus brain abscess in a child with acute lymphoblastic leukemia.

Cerebral aspergillosis carries a high mortality in immunocompromised patients. However, favorable outcome can be achieved by the prolonged use of antifungal agents and the maintenance of adequate drug levels. The authors report a 2-year-old girl who developed an aspergillus brain abscess during treatment for acute lymphoblastic leukemia. Predisposing factors for the fungal infection and details of the antifungal therapy are described. Prolonged treatment with AmBisome and 5-flucytosine successfully eradicated the lesion, but the girl's antileukemic therapy was compromised due to the infection. She developed a central nervous system and bone marrow relapse 9 and 15 months, respectively, after the initial presentation. The report emphasizes the need for further consideration of effective, long-term antifungal prophylaxis and a careful balance between aggressive treatment for severe infection and antileukemic therapy.

Fibromuscular hyperplasia of the internal carotid artery. A further cause of the 'moyamoya' collateral circulation.

Fibromuscular hyperplasia is a rare cause of internal carotid artery occlusion. We present a case where long stenoses of both internal carotid arteries were associated with terminal carotid occlusions and a ruptured basilar aneurysm.

Prevention of bone loss by hormone replacement therapy is probably not due to stimulation of calcitonin secretion.

Weekly fasting serum calcitonin levels and biochemical indices of bone metabolism were measured in 13 postmenopausal women being given hormone replacement therapy over a period of 8 weeks. All of the biochemical indices except urinary hydroxyproline creatinine ratios fell significantly, indicating that the treatments were effective in reducing bone turnover. Calcitonin levels fell significantly and, within the individual, levels were positively correlated with adjusted calcium levels. These findings do not support the theory that estrogen conserves bone by stimulating calcitonin secretion.

Systems analysis of cerebrovascular pressure transmission: an observational study in head-injured patients.

In an observational study in head-injured patients, cerebrovascular pressure transmission was investigated using a systems analysis approach whereby the blood pressure (BP) waveform was used as a measure of an input stimulus to the cerebrovascular bed (CVB) and the intracranial pressure (ICP) waveform as the response to that stimulus. The transfer function is a measure of how much pressure is transmitted through the CVB at a given frequency and is calculated using Fourier analysis of the pressure waveforms. The transfer function allows quantification of the pressure transmission performance of the CVB, thus providing a basis for comparison between normal and abnormal function. Fifteen hundred samples of ICP and BP waveforms were collected from 30 head-injured patients via microcomputer. Off-line spectral analysis of the waveform database revealed four main classes of transfer function: those with an overall flat transfer function (curve type 1); those with an elevated low-frequency response (curve type 2); those with an elevated high-frequency response (curve type 3); and those exhibiting both an elevated low- and high-frequency response (curve type 4). Curve types 2 and 4 were most often associated with raised ICP (greater than 20 mm Hg), whereas curve types 1 and 3 were most often affiliated with ICP less than 15 mm Hg. Studies of this type may provide insight into the pathophysiology of the CVB and ultimately aid in the prediction and treatment of raised ICP.

Aqueduct stenosis--presentation and prognosis.

In the 14-year period from 1974-1987 during which CT scanning was available in Edinburgh, 36 patients with benign, non-tumour related aqueduct stenosis were identified from a group of 342 patients with hydrocephalus. In terms of age at presentation, the patients separate into two groups, 9 cases diagnosed during the first year of life and 27 patients aged from 7 to 72 years. The presentation in the early cases was fairly acute, the diagnosis was secure and the operative treatment by ventricular peritoneal shunt was relatively free of complications. In the older patients, the first presentation was more chronic, and further investigation required a change of diagnosis in 5 of the 27 patients. More than half of the patients had recurrent symptoms which were much more acute and operative treatment was attended by a significant number of complications including death from intraventricular haemorrhage in one case.

Extradural haematoma in infants.

The clinical and operative findings of 40 infants treated for Extradural Haematomas (EDH) between 1960 and 1988 are presented. This series represents 19% of the total number of children with EDH during this period. Twenty-five (63%) were male, fifteen (37%) female. They were divided into three groups according to age for comparison. Group A, less than 6 months (11 cases); group B, 7-12 months (16 cases); and group C, 13-24 months (13 cases). Sixteen (40%) resulted from falls less than 1 m. Seven (17.5%) fell whilst walking. Twelve (30%) fell more than 1 m. Two EDH followed obstetric trauma, three occurred as a result of a road traffic accident. A lucid interval was identified in 30 cases, and in 15 it was longer than 24 h. Drowsiness (60%), and delayed vomiting (45%), were the most important symptoms. Anaemia occurred in 19 (47.5%). Thirty-six (90%) had abnormal skull X-rays. Thirty (75%) EDH were parietal, temporal, or temporo-parietal. Two were located in the posterior fossa. There were no frontal EDH in this series in contrast to that found in older children. Twenty-seven (67.5%) EDH were larger than 75 cc in volume. The source of bleeding was identified in 31; in 17 (42.5%) it was from the middle meningeal artery; in 11 (27.5%) from the bone; and in three (7.5%) from the dural surface. The mortality was 12.5% with a 15% morbidity rate, three infants (7.5%), suffering motor deficits, and three requiring medical treatment for epilepsy.

Role of a separate subcutaneous cerebro-spinal fluid reservoir in the management of hydrocephalus.

A retrospective survey has been carried out on 56 children with shunted hydrocephalus either with a primary idiopathic cause or as a result of a low spina bifida complex. In all 56 children, a separate reservoir has been inserted at some stage in the management of their hydrocephalus. There was no mortality. Morbidity was not increased from CSF infection or shunt blockage. There was less chance of the initial shunt blocking and there was a lesser incidence of visual and schooling handicap. Double cortical puncture did not result in an increased incidence of hemiplegia or epilepsy. We conclude that a separate reservoir greatly eases the management of these children and does not cause significant increased morbidity.

Effect of subdermal oestrogen and oestrogen/testosterone implants on calcium and phosphorus homeostasis after oophorectomy.

Various biochemical aspects of calcium metabolism were studied serially in 32 post-menopausal patients treated with subdermal implants of oestrogen, either alone or in combination with testosterone. Significant reductions in serum calcium, serum phosphate, the renal phosphate threshold (TmPO4) and the urinary calcium/creatinine ratio were observed for periods of up to 6 mth in both treatment groups as compared with baseline. The findings suggest that oestrogen replacement therapy by subdermal implant is effective in reversing the characteristic alterations in calcium metabolism which occur in the post-menopausal patient. The addition of testosterone does not appear to confer any additional benefit with respect to the parameters assessed.

Effect on lipoproteins of Trisequens, a combined hormone preparation.

Lipoprotein concentrations were measured in 31 post-menopausal women during 1 yr of treatment with Trisequens, a natural oestrogen-progestogen preparation. Serum triglyceride, high density lipoprotein and very low density lipoprotein cholesterol concentrations did not change significantly, but low density lipoprotein cholesterol concentrations fell over the first 6 mth. After 1 yr none of the lipoprotein fractions differed significantly in concentration from pre-treatment levels.

Calcitonin and postmenopausal osteoporosis.

Fasting serum calcitonin levels were measured in 54 postmenopausal women who had for 10 years been taking part in a double blind trial to assess the effect of the synthetic oestrogen, mestranol, on postmenopausal bone loss. There were no differences in calcitonin levels between mestranol treated and placebo groups. Fifteen of the women were challenged with a calcium infusion to measure the secretory reserve of calcitonin. Oestrogen treatment did not increase the calcitonin response to calcium infusion. The three patients who exhibited the greatest responses were placebo treated. Bone density was measured by gamma-ray absorptiometry over the ten year period and the annual rate of change of bone density calculated. No correlation could be found between basal calcitonin level or calcitonin reserve and change in bone density. Our results indicate that postmenopausal osteoporosis is not caused by a deficiency of calcitonin and that the action of oestrogen therapy to prevent bone loss does not involve calcitonin.