Rate-responsive pacemakers and anaesthesia A consideration of possible implications

A new generation of pacemakers has been developed in recent years which adjust the pacing rate according to changes in physiological variables. The selected parameters are affected during physical activity that involves an increased heart rate in healthy humans. The variables include body movements, QT interval, breathing, temperature, myocardial contractility, oxygen saturation and changes in blood pH which may be influenced during general anaesthesia, and can lead to unphysiological, high, pacing rates. It is important to be familiar with the pacemaker and its functions before administration of anaesthesia in order to prevent complications. Rate-responsive pacemakers in such situations should be programmed to exclude the rate-responsive function.     

Central Clinical Research Issues in Electrophysiology: Report of the NASPE Committee

DOMANSKI, M.J., et al. : Central Clinical Research Issues in Electrophysiology: Report of the NASPE Committee. This article contains the results of an attempt by appointed members of the North American Society of Pacing and Electrophysiology to define the research frontier in electrophysiology and suggest areas of study as an aid in setting the research agenda.     

Plasma aldosterone during extracellular fluid volume expansion in patients on regular haemodialysis

The influence of extracellular fluid volume expansion on the plasma aldosterone concentration (PAC) was investigated in five anephric and six non-nephrectomized patients on regular haemodialysis, and compared to a control group of four anephric and four non-nephrectomized patients. Plasma-renin activity, cortisol, Na+, and K+ were measured together with the PAC during the investigation. In anephric patients the PAC remained constant during the control period as well as during extracellular fluid volume expansion by infusion of 350 mmol of 20% mannitol. In the non-nephrectomized patients PAC diminished after mannitol infusion. The decline in PAC was correlated with the basal levels of PAC and the plasma renin activity. It is concluded that 5% extracellular fluid volume expansion has no direct influence on the regulation of PAC in patients without the renal renin-angiotensin system and that the regulation of PAC in anephric patients in the present investigation is probably mediated by changes in potassium and ACTH.     

Effect of chlorhexidine mouthrinse and periodontal treatment upon bacteremia produced by oral hygiene procedures

ABSTRACT – Toothbrushing for 2¹/₂ min and the use of toothpicks for 2¹/2 min produced bacteremia with streptococci in seven out of 13 patirnts with destructive periodontitis and in dontitis group and the "gingivitis" group was not significant, but there scemed to be more frequent bacteremia in the periodontal group. No correlation could be established between plaque-index, gingival-index and positive bacteremia. Barteremia seemed to be due primarily to pockets and interdental ulcerations. The use of chlorhexidine as a mouthriuse for 7 d did not reduce the bacteremia caused by the oral hygiene procedures in either of the two groups. After periodontal treatment no bacteremia was detected in the periodontitis group, whereas no reduction was obtained in the gingivitis group.