Key result
Halothane anesthesia reduces LV percentage shortening by ~40% and increases diastolic minor axis vs control.
Why the study?
The effects of halothane anesthesia on left ventricular volume and cardiac performance in normal subjects were not fully characterized using echocardiography.
Does halothane anesthesia alter left ventricular volume and cardiac performance in normal subjects?
Does halothane anesthesia alter left ventricular volume and cardiac performance in normal subjects?
Halothane anesthesia causes dose-dependent cardiac dilation and depressed left ventricular performance, which can be effectively monitored using echocardiography.
May prompt echocardiographic monitoring of halothane effects; leaves open relevance to patients with cardiac disease or clinical outcomes.
Using M-mode echocardiography we found that 0.5, 1.0, and 1.5% end-tidal halothane induced dose-related increases in left ventricular volume and decreases in left ventricular performance in seven normal unpremedicated subjects. During controlled respiration with normocarbia, the diastolic minor axis of the heart, which is related to the cube root of left ventricular volume, increased to a maximum of 107. 7 +/- 1.9 (% +/- SE of control) at 1.5% end-tidal halothane from a control value of 43.5 +/- 1.3 (mm +/- SE). Two ejection-phase performance variables, percentage shortening and mean velocity of circumferential shortening decreased to 60.1 +/- 6.1 (% +/- SE of control) and 62.4 +/- 6.5, (% +/- SE of control) at 1.5% halothane from respective control values of 29.7 +/- 2.61 (% +/- SE) and 0.94 +/- 0.08 (circumferences/second +/- SE). Surgical stimulation did not significantly affect these changes. Under these experimental conditions, we conclude that halothane dilates the heart, and that echocardiography can be used to monitor the depressant effect of halothane on the heart.
No takes yet. Share an insight, caveat, or question.
Gerson et al. (1979) studied Healthy subjects (n=7). Halothane vs. Baseline (control) was evaluated on Left ventricular volume and performance (diastolic minor axis, percentage shortening, mean velocity of circumferential shortening). Halothane anesthesia at 1.5% end-tidal concentration increased the diastolic minor axis to 107.7% of control and decreased percentage shortening to 60.1% of control in normal subjects.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: