Reflex Cardiorespiratory Effects of Nociceptive Oesophageal Distension in the Decerebrate Rat

It is well established that painful distension of hollow viscera such as the oesophagus can evoke a reflex tachycardia and pressor response; however, the nature of the oesophageal afferent pathway(s) remains controversial. This study investigated the afferent arc which mediates these reflex cardiovascular changes in the decerebrate rat. In addition, the effect of oesophageal distension on the respiratory activity of the costal diaphragm was studied. Focal distension of the oesophagus (volume of 0.3 ml applied for 10 s) just above the diaphragmatic hiatus evoked a reproducible pressor response and tachycardia in the decerebrate rat. Respiration was transiently inhibited at the beginning of oesophageal distension and prior to the rise in blood pressure. Neuromuscular blockade with the nicotinic acetylcholine receptor blocker alpha-bungarotoxin (140 microg bolus) had no effect on the magnitude of the cardiovascular response. Therefore the efferent supply to the striated muscle of the rat oesophagus was not essential in mediating this reflex. Signal averaging of the mean blood pressure response showed that neither selective ablation of oesophageal spinal afferents nor bilateral vagotomy altered the early trajectory of the pressure response. Bilateral vagotomy reduced the peak magnitude of the response to sustained oesophageal distension. In contrast, selective removal of spinal afferents had no effect on the response. Ablation of both neural pathways was essential to abolish the reflex cardiovascular and respiratory responses. It can be concluded that both vagal and spinal afferent pathways are utilised in the reflex cardiorespiratory response to painful oesophageal distension. Although ablation of one neural pathway had no effect on the response it was still implicated in the reflex, since ablation of both pathways was necessary to prevent the cardiorespiratory changes. This study emphasises the need for caution when inferences are made concerning single selective ablations of multiply innervated organs.     

Concurrent review of the duration of antimicrobial prophylaxis in surgery.

The administration of prophylactic antibiotics in surgery is appropriate for many patients. Data have shown extending the duration of prophylaxis beyond 48 hours does not lower the rate of postoperative-infection. The purpose of this project was to concurrently assess the duration of prophylactic antibiotic use. A total of 95 patients were monitored over 3 weeks. Eighty patients (84.2%) received antimicrobial therapy. In 23 of these patients (28.75%) the duration of antibiotic administration was longer than 2 days without clinical or microbiological evidence of infection. In 5 other patients only postoperative antibiotics were prescribed. The cost difference between the actual duration of antibiotic administration and 2 days of the same regimen was +1,364.58. Extrapolating for one year, it can be estimated that antibiotic costs could be reduced about +23,600. Pharmacists can focus on the duration of antibiotic prophylaxis as a cost containment measure.     

The General Practice Research Club.

The General Practice Research Club was established in 1969, and now has 120 members. A meeting of the club is held twice a year, at which various papers, from research ideas through to completed, published studies are presented. A survey of 40 individuals who had presented papers at meetings during the period 1984-89 showed that almost half (18) had presented papers on clinical topics. As a result of the presentation, 29 individuals had modified their research, with 11 undertaking major alterations. The meeting was rated most highly by those offering ideas and plans for research. Most individuals responded positively to the meetings, commenting that they valued peer review, found the meetings encouraging, and useful for focusing ideas. Lack of criticism and feedback was commented upon. The club has an important role to play in encouraging research by service general practitioners.     

CT evaluation of Crohn's disease: effect on patient management

CT scans from 80 consecutive patients with clinically symptomatic Crohn's disease were reviewed retrospectively to determine the effect of CT diagnosis on patient management. The initial clinical impression and any subsequent change in patient management because of the CT findings were noted. In 22 (28%) of the 80 patients, significant previously unsuspected findings led to a change in medical or surgical management. These included 12 patients with fistulae, four with abscess, two with avascular necrosis of the femoral head, two with sacral osteomyelitis, and single cases of pelvic inflammatory disease and femoral vein thrombosis.     

Is neighbourhood deprivation a risk factor for gestational diabetes mellitus?

AIMS: To assess the relationship between neighbourhood deprivation and the rate of gestational diabetes mellitus (GDM) using routinely collected data from a clinical information system, in Plymouth, UK. METHODS: Between 1 January 1996 and 31 December 1997, 3933 women residing within the Plymouth Primary Care Trust (PCT) were screened for GDM using indices of neighbourhood deprivation and prevalence of GDM. Areas (n = 43) were classified according to the Townsend index, measuring material deprivation. Pregnant women with and without GDM were compared. RESULTS: The prevalence of GDM was 1.7%[95%, confidence interval (CI) 1.20, 2.11]. The prevalence of GDM ranged from 1.05% (95% CI 0.60, 1.70) in the most deprived to 2.10% (95%, CI 1.34, 3.13), in the least deprived neighbourhood. Crude rates decreased by 50%[relative prevalence (RP) (95% CI) 0.50 (0.27, 0.94); P = 0.06] amongst those living in the most-deprived compared with those living in the least-deprived areas. Using a stepwise binary logistic regression model, older age at delivery significantly increased the risk of developing GDM. [RP (95%, CI) 1.09, (1.04, 1.13)]. Townsend deprivation score had no significant independent association with GDM when other covariates were considered. CONCLUSION: These data suggest that the neighbourhood context in which women live has no impact on the risk of GDM. Diabet.     

Local mucosal immunoglobulin E production: does allergy exist in non‐allergic rhinitis?

In this review, we critically evaluate the evidence for local IgE production in allergic rhinitis mucosa and the concept of local allergy in non-atopic idiopathic rhinitis. Significantly, fewer studies have focused on the disease pathways associated with non-allergic rhinitis compared with their allergic counterparts. Recently, there's been a revival of the hypothesis concerning the existence of local tissue-specific allergic disease confined to the nasal mucosa of some systemically non-atopic rhinitis subjects. Providing the evidence for local mucosal IgE production in allergic rhinitis is a pre-requisite to reviewing its existence in non-allergic rhinitis. In addition, practical and theoretical approaches useful in the detection of allergy in non-allergic rhinitis will be discussed. Furthermore, successful therapeutic regimens used in the treatment of non-allergic rhinitis will be examined as these could provide an insight into the underlying pathophysiology of this common but poorly understood disease.