Korean J Anesthesiol.  1999 Nov;37(5):739-744. 10.4097/kjae.1999.37.5.739.

Correlation between the Degree of Bradycardia in Strabismus Surgery with Linear and Nonlinear Analysis of Preoperative Electrocardiogram

• Kim HS
• Seo KS
• Jung YB
• Kim CS
• Yum MK

• KMID: 2239002
• DOI: http://doi.org/10.4097/kjae.1999.37.5.739

Abstract

BACKGROUND: Severe bradycardia occurring in strabismus surgery is unpredictable and may lead to cardiac arrest. If we identify patients who have risk of severe bradycardia during strabismus surgery, it is helpful to provide a more meticulous anesthesia. In this study, we investigated the correlation between the degree of bradycardia and indices of power spectral analysis and nonlinear dynamic data analysis of preoperative ECG.
METHODS
ECG was collected for twenty minutes from strabismus patients (n = 93). No premedicants were administered. After administration of anesthesia and traction of extraocular muscle, the lowest heart rate was recorded. We calculated the correlation coefficient between the power spectral density, approximate entropy and correlation dimension of preoperative ECG and the difference between preoperative and lowest HR.
RESULTS
As the difference between the preoperative heart rate and the intraoperative bradycardia increased, the preoperative ECG showed a low total power (r = 0.27, P = 0.016), low low-frequency power (r = 0.31, P = 0.049), low high-frequency power (r = 0.30, P = 0.007) and high ratio of low to high-frequency power (r = 28, P = 0.03). There was no correlation between bradycardia and approximate entropy and correlation dimension, respectively.
CONCLUSIONS
There was a correlation between indices of power spectral analysis of preoperative ECG and degree of bradycardia during strabismus surgery. Therefore we take into consideration preoperative ECG and its analytic indices in order to provide careful preparation for high risk patients who exhibit a tendency to severe bradycardia.

Keyword

Anesthesia, pediatric; Heart, heart rate variability; Reflex, oculocardiac

MeSH Terms

Anesthesia
Bradycardia*
Electrocardiography*
Entropy
Heart Arrest
Heart Rate
Humans
Nonlinear Dynamics
Reflex, Oculocardiac
Statistics as Topic
Strabismus*
Traction