Heat loss during thoracotomy.

Abstract

This has been evolved with a modified pulse duplicator and the use of a hot film probe for measuring velocity, direction, and turbulence. Many of the commercially available mitral valve prostheses are being investigated for their flow characteristics. In addition, efficiency is being examined and some unusual findings point to the possibility of a hydraulic ram effect in the normal mitral valve that allows opening to commence before the end of ventricular systole.TRIAL OF A NEW ANTI-MYXOVIRUS COMPOUND J. E. STARK Two hundred and sixty-four male students living in a hall of residence volunteered to take part in the trial and were randomly allocated into two groups. One group received a synthetic isoquinoline derivative (UK. 2371) daily in divided doses and the other group received identical placebo tablets.During the five weeks of the trial tablets were distributed daily and volunteers were asked to return any tablets which had not been taken. As an additional guide to tablet acceptance a small quantity of isoniazid was incorporated into some active and placebo tablets and urine samples collected at appropriate times were tested for isoniazid derivatives.Volunteers were questioned each week about their health and were asked to report all respiratory and other illnesses. All respiratory illnesses were fully investigated for virus and mycoplasma infections. Full toxicity studies were carried out.The preliminary findings are reported with particular reference to (1) protection against acute respiratory illness provided by the drug; (2) assessment of the novel isoniazid marker system; and (3) the factors affecting acceptance of medication by volunteers.MYCOPLASMA PNEUMONIAE M. C. JONES A retrospective study was made of 100 cases of infection with Mycoplav.n nneumoniae notified through the Public Health Laboratory four-weekly review during 1967-68, and diagnosed by isolation or complement fixation studies. The mode of presentation, physical, radiological and haematological findings, complications, treatment, and progress are reported.The results are also presented of an investigation into the isolation rate of Mycoplasma species (including pneumoniae, hominis, orale, and salivarium) from the nasopharynx of patients admitted to hospital with acute exacerbations of asthma, bronchitis or bronchiectasis and from the nasopharynx and bronchial tree of patients submitted to bronchoscopy. We measured the heat debt incurred during thoracotomy, first with no particular measures taken to prevent heat loss and, secondly, using a heat-reflecting aluminium foil blanket wrapped around the lower half of the patient.Our method of measuring heat loss was adapted from that of Burton and Benzinger. Deep body, calf, forearm, and abdominal skin temperatures were measured. From these readings the average body temperature and the change in heat content were calculated.Our results are of interest for several reasons: 1. The average heat debt without precautions against heat loss was 20 Kals per hour. This involves a doubling of the metabolic ...

Peripheral vasoconstriction after open-heart surgery

“…Loss of total body heat has been shown by various workers (Pembrey and Shipway, 1918;Dyde and Lunn, 1969;Lunn, 1969) to occur during many forms of surgery, and postoperative vasoconstriction could be explained on the basis that it protects against further heat loss until muscle and metabolic activity have made good the debt. If all patients developed an approximately similar debt then all would require an approximately similar time to rewarm (as seen here) provided the circulation was adequate.…”

Metallized Plastic Sheeting in the Prevention of Hypothermia During Neurosurgery

“…pre-warmed gel-filled mattresses (Winder and Vale, 1970), blankets with circulating warm liquid (Newman, 1971;Morris and Kumar, 1972), suits with circulating warm liquid (Goldblatt and Miller, 1972), humidification of inspired gases (Newton, 1975), and metallized plastic sheeting (m.p.s.) (Dyde and Lunn, 1970).…”

“…Each blanket consists of two layers of m.p.s. separated by an artificial fibre layer and measures 2.11 m by 1.42 m. Dyde and Lunn (1970) had used m.p.s. previously in thoracic surgery but, although several neurosurgical centres in this country use m.p.s.…”

Humidification and Loss of Body Heat During Anaesthesia: Ii: Effects in Surgical Patients

“…Large heat losses during operation have been reported (Lunn, 1969;Vale and Lunn, 1969;Dyde and Lunn, 1970), where control groups had mean losses of some 21 kcal per hour during thoracotomy. In those series, it would appear that the fluids administered intravenously were not warmed.…”