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Håkan Elmqvist

Publications and source records attributed to Håkan Elmqvist.

3 recordsLinked to original sources

Improved capacity of exercise electrocardiography in the detection of coronary artery disease by focusing on diagnostic variables during the early recovery phase.

The temporal distribution of the diagnostic information for the detection of coronary artery disease (CAD) provided by exercise-induced electrocardiographic (ECG) ST-segment amplitude changes in different ECG leads in men and women has not been fully investigated. To shed further light in this area, 1877 electrocardiograms selected from 8322 patients undergoing a routine exercise test on a bicycle ergometer were evaluated. ST-segment amplitude and the difference between heart rate-matched recovery and exercise ST-segment amplitudes (ST/HR difference) were measured. Coronary artery disease was verified angiographically in 669 patients and excluded in 1208 patients by angiography (n = 119), by myocardial scintigraphy (n = 250), or on clinical grounds (n = 839). The diagnostic performance of the 2 ECG methods used was assessed by constructing receiver operating characteristic curves for each sampling point every 12 seconds during 10 minutes of recovery as well as the last 4 minutes of exercise for the ST-segment amplitude. ST-segment amplitude performed better after exercise than during exercise and best within the first 2 minutes of recovery. Its diagnostic ability did not differ from the ST-amplitude hysteresis assessed by the difference between recovery ST-segment amplitude and exercise ST-segment amplitude at matched heart rate. Both methods performed better in men and the diagnostic information appeared mainly in leads I, -aVR, II, V 4 , V 5 , and V 6 . The best discrimination of CAD is provided by analysis of ST-segment amplitude changes in 6 specific leads early during the recovery phase. This information should be targeted by exercise ECG diagnostic methods.

Coronary Angiography↗

Topical humidified carbon dioxide to keep the open surgical wound warm: the greenhouse effect revisited.

BACKGROUND: Perioperative hypothermia is common in open surgery and is associated with increased rates of wound infection. This is a result of decreased wound tissue oxygenation, which can be normalized by local warming. Recently, a technique has been developed to establish a carbon dioxide atmosphere in an open surgical wound. Therefore, the authors studied the possible "greenhouse effect" of carbon dioxide insufflation and operation lamps on wound temperature. METHODS: In a fully ventilated operating room surface temperature was measured at steady state in a model of an open surgical wound containing blood agar. The wound model was randomized to either no insufflation or insufflation of dry and humidified carbon dioxide or air, respectively, at a flow of 5 l/min via a gas diffuser. The surface temperature was measured with operation lamps switched on and off, respectively. Evaporation rates were also measured. RESULTS: With the operation light off, the surface temperature in the control was 31.8 degrees C, and with the operation light on, the temperature increased by 1.5 degrees C (P < 0.001). Additional insufflation of dry carbon dioxide increased the surface temperature another 1.9 degrees C (P < 0.001). When the carbon dioxide was humidified, the evaporation rate was lowest and the surface temperature increased further to 35.6 degrees C (P = 0.002). In contrast, insufflation of dry and humidified air did not have a significant effect on the evaporation rate and only marginally increased the wound temperature in comparison with the control. CONCLUSIONS: Insufflation of humidified carbon dioxide in combination with light from the operation lamps may help to keep the open wound warm during surgery.

Body Temperature↗