A bump in the night: a 15-year retrospective analysis of urgent inpatient and emergency CT reporting out of hours in a tertiary referral centre.

AIM: To assess the impact on specialty trainee (ST) experience of out-of-hours (OOH) working, focusing on what might be improved with both patient safety and staff wellbeing in mind. MATERIALS AND METHODS: The number of acute computed tomography (CT) examinations reported OOH over the last 15 years (2007-2021) at Oxford University Hospitals NHS Foundation Trust was analysed. Qualitative data from the radiology STs participating in the acute OOH rotas were obtained using questionnaires during winter months in 2019 and 2021, before and after the introduction of an OOH CT outsourcing service in 2020. RESULTS: Overnight acute CT has increased over 10-fold over the last decade to almost 50 CT examinations in 2021, and similar increases were observed during evening and weekend shifts. The option to outsource acute CT on an ad hoc basis was introduced in 2020 to manage the increase in demand. This resulted in a statistically significant improvement in the STs' level of reported satisfaction for OOH shifts (p<0.018), despite significantly increased perception of how busy the shifts were (p<0.035). CONCLUSION: OOH acute CT reporting at Oxford NHS Foundation Trust has increased dramatically over the previous 15 years. Working patterns and resources have changed incrementally to absorb this increase in demand, most recently with the option for outsourcing at times of peak demand. The trend for increasing OOH CT demand has considerable implications for future resource planning.

Occurrence of synchronous invasive lobular breast carcinoma and poorly differentiated ovarian carcinoma in a single peritoneal deposit.

The synchronous occurrence of breast and ovarian cancers within individual omental metastases has not been reported in the available medical literature. We report such a finding in a patient with previously diagnosed invasive lobular carcinoma of the right breast. After 5 years of surveillance and disease-free interval, there was development of ovarian cancer, ascites and peritoneal metastases. Ultrasound-guided biopsy of a peritoneal metastasis confirmed dual histology from breast and ovarian carcinoma. Despite the presence of a prolonged disease-free survival from the primary breast cancer, the subsequent finding of advanced ovarian cancer highlights the potential diagnostic and therapeutic dilemmas which persist in the management of these patients.

Mechanoelectric feedback in the atrium of the isolated guinea-pig heart.

OBJECTIVES: Atrial arrhythmias are prevalent during clinically abnormal myocardial loading, e.g. when the atrium is dilated or stretched. The initiating cause of the first premature beat that leads to this arrhythmia is unclear, as are the reasons for sustaining it. One possibility is that abnormal mechanical factors induce electrophysiological changes conductive to arrhythmia via 'mechanoelectric feedback'. The aim of this study is to investigate the concept that atrial stretch modulates the electrophysiological properties of the atrium via mechanoelectric feedback, and that mechanoelectric feedback can produce atrial arrhythmias. METHODS: Guinea-pigs were humanely killed by cervical dislocation and the hearts removed and perfused with oxygenated Krebs-Henseleit solution by the Langendorff method. The heart was paced at an atrial site near the sinus node. Monophasic action potentials and electrocardiograms were recorded form the left atrium and left ventricle with suction electrodes. Transient stretch was induced by inflating a fluid-filled intra-atrial latex balloon catheter. RESULTS: Increase in atrial volume produced several significant changes in the epicardial monophasic action potentials. It produced (i) decreases in the amplitude; (ii) a decrease in duration from 62.55 to 51.95 ms measured at 50% repolarisation (10.6 +/- 3.6 ms, P < 0.05, n = 6); (iii) an increase in duration from 122.45 to 140 ms measured at 90% repolarisation (17.55 +/- 4.5 ms, P < 0.05, n = 6) --due to the presence of early afterdepolarisations. (iv) These load-induced electrophysiological changes coincided with the occurrence of arrhythmia or premature atrial beats. CONCLUSIONS: Load changes in the atrium can produce electrophysiological changes of a kind that may be relevant to clinical atrial arrhythmia.

Regional workload induced changes in electrophysiology and immediate early gene expression in intact in situ porcine heart.

Cardiac remodelling and hypertrophy induced by chronic haemodynamic overload (stretch) eventually leads to a decrease in cardiac function, an increased incidence of ventricular arrhythmia and mortality. The mechanisms by which myocytes sense haemodynamic stress and activate growth signals are largely unknown. Nuclear immediate early genes may act as third messengers, converting the stretch stimulus into long-term changes of gene expression via cytoplasmic signal transduction. However, previous studies have used cell cultures and isolated hearts, neither of which are ideal models. We have developed a new in situ porcine heart model where local strain (stretch) can be applied, for several hours if required, thus allowing the comparison of changes in electrophysiology and gene expression with unstrained myocardium in the same preparation. A pneumatically controlled stretch-device was attached to a portion of the right ventricle of an anaesthetized animal using suction. Chronic stretch was applied for 30 min or 1 h. Regional loading produced (i) a transient decrease in monophasic action potential duration (3.5+/-0.8%; P<0.05), followed by (ii) an elongation by 15 min, despite maintained stretch (3.4+/-1.5%; P<0.05 compared to the pre-stretch situation). A control segment of the right ventricle did not show these changes. Northern blot analysis showed that both c-fos and c-myc were induced in the areas sampled, but they were 12-fold and three-fold higher, respectively, in stretched compared with control tissue after 30 min. Thus, prolonged regional stretch can produce complex changes in cardiac electrophysiology and increase expression of some immediate early genes. Our model may be useful for studying the cascade of events that lead to remodelling, hypertrophy, and arrhythmia.