Reversible attenuation of voltage of QRS complexes and P waves and shortening of QRS duration and QTc interval consequent to large perioperative intravenous fluid infusions.

A 39-year-old woman with a gangrenous pyelonephritis and septic shock underwent a nephrectomy, in preparation for which, she received large preoperative fluid resuscitation. Quantitative evaluation of her serial standard electrocardiograms (ECGs) revealed reversible attenuation of voltage in association with peripheral edema (PERE), with the latter being eventually completely abolished. The transient low-voltage ECG (LVECG) (attenuated amplitudes of QRS complexes) was associated with parallel transient attenuation of the amplitude of P waves and shortening of the QRS duration and QTc, whereas the P-wave duration increased. Awareness of these ECG changes with PERE of varying pathophysiologic mechanisms is useful, ensuring avoidance of improper procedural and laboratory testing and correct measurement of wave amplitudes and ECG time intervals for proper ECG diagnosis. In addition, these ECG associations can be used as indices of the presence and course of PERE postoperatively, as well as in a large variety of medical settings.