An unusual cause of hypoxia: getting to the heart of the matter

A 63-year-old female presented to hospital with progressive exertional dyspnoea over a 6-month period. In the year preceding her admission, she reported an intercurrent history of abdominal pain, diarrhoea and weight loss. She was found to be hypoxic, the cause for which was initially unclear. A ventilation–perfusion scan identified a right-to-left shunt. Transoesophageal echocardiography (TOE) demonstrated a significant right-to-left intracardiac shunt through a patent foramen ovale (PFO); additionally severe tricuspid regurgitation was noted through a highly abnormal tricuspid valve. The findings were consistent with carcinoid heart disease with a haemodynamically significant shunt, resulting in profound systemic hypoxia. 24-h urinary 5-hydroxyindoleacetic acid (5-HIAA) and imaging were consistent with a terminal ileal primary carcinoid cancer with hepatic metastasis. Liver biopsy confirmed a tissue diagnosis. The patient was commenced on medical therapy for carcinoid syndrome. She subsequently passed away while undergoing anaesthetic induction for valvular surgery to treat her carcinoid heart disease and PFO

The longitude problem from the 1700s to today: An international and general education physics course

For instructors wishing to use physics as part of an international or general education course, the framework for a course based on the “longitude problem” from the 1700s is described. The longitude problem is teeming with basic principles of physics and astronomy, which makes it ideal for a non-science-major-based college-level course. This paper summarizes the longitude problem in the context of conceptual physics and astronomy and outlines an appropriate curriculum. Specifics on teaching such a course in London, as part of an international studies program, are discussed

THE EFFECT OF SUBSTRATE LOAD AND BLOOD-GLUCOSE MANAGEMENT ON CEREBRAL-DYSFUNCTION FOLLOWING CARDIOPULMONARY BYPASS

Seventy patients undergoing elective coronary artery bypass grafting were prospectively randomized into either of two primes: 5% dextrose or Hartmann's solution. The groups were comparable. Neuropsychological assessment was performed before and eight weeks after surgery. During bypass blood glucose concentrations rose to a mean of 26 mmol/L in the 5% dextrose group and 6 mmol/L in the Hartmann's group. No deaths occurred in either group; 2 clinically evident neurological events were noted, both taking place in the hyperglycemic group. Detailed analysis of the results showed differences between the groups. When score changes between tests were assessed it was found that in 17 of the 18 versions of the tests more patients in the hyperglycemic group deteriorated than the norinoglycemic controls. With a two-tailed binomial statistic this difference was significant at the 5% level. Learning ability was likewise found to worsen in the hyperglycemic group after surgery.Hyperglycemia may be a detrimental factor in the development of postcardiac surgical intellectual dysfunction. The authors would advocate the avoidance of glucose-containing bypass primes and the close monitoring of blood glucose during cardiopulmonary bypass