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A single-blinded case controlled study on effects of cardiopulmonary circulation on hearing during coronary artery
A J Donne1, P Waterman, L Crawford
1Department of Otolaryngology, Blackpool Victoria Hospital, Whinney Heys Road, Blackpool, Lancashire, UK. ajdonne@doctors.org.uk
Insights
This study found no significant hearing loss in patients undergoing coronary artery bypass grafting (CABG) with or without cardiopulmonary bypass. Hearing outcomes were similar for both on-pump and off-pump procedures.
Area of Science:
- Cardiology
- Otolaryngology
- Surgical Outcomes
Background:
- Coronary artery bypass grafting (CABG) is a common surgical procedure.
- The use of cardiopulmonary bypass (CPB) during CABG raises concerns about potential auditory system effects.
- Understanding the impact of CPB on hearing is crucial for patient care.
Purpose of the Study:
- To investigate the effect of extra-corporeal (cardiopulmonary) bypass on hearing in patients undergoing coronary artery bypass grafting.
- To compare hearing outcomes between patients undergoing on-pump versus off-pump CABG.
Main Methods:
- A prospective, single-blinded, controlled study was conducted.
- Fifty-two patients undergoing CABG were included, with 38 on-pump and 14 off-pump.
- Pure tone audiograms were performed pre- and post-operatively to assess hearing changes.
Main Results:
- No statistically significant difference was found in hearing between pre- and post-operative audiograms for all patients.
- No significant differences in hearing were observed when comparing on-pump versus off-pump CABG patients.
- Hearing outcomes were not significantly affected by the number of bypass vessels or duration on CPB.
Conclusions:
- Extra-corporeal (cardiopulmonary) bypass does not appear to have a statistically significant deleterious effect on hearing during coronary artery bypass grafting.
- The findings suggest that CPB is safe concerning hearing function in CABG patients.
- Further research may explore long-term auditory effects or specific patient populations.
Objectives:
To evaluate the effect of extra-corporeal (cardiopulmonary) bypass on hearing during coronary artery bypass grafting.
Design:
Prospective (single-blinded) controlled study.
Setting:
District General Hospital.
Participants:
Fifty-two patients undergoing coronary artery bypass grafting completed this study. Comparison was made between 14 control patients undergoing off-pump coronary artery bypass grafting and 38 study patients undergoing on-pump coronary artery bypass grafting. The age range of patients was 48-81 years, with 50% between 64 and 66 years.
Main Outcome Measures:
Pure tone audiograms were performed in all patients before and after coronary artery bypass grafting. Data were analysed for any significant difference between pre- and post-operative pure tone audiograms.
Results:
Mann-Whitney U-test demonstrated no difference between the area generated between mean pre- and post-operative audiograms (P = 0.754). No significant difference between off versus on pump was demonstrated for average differences at 250-500 Hz, 4 kHz, 4-8 kHz and 8 kHz. Wilcoxon matched-pairs signed-rank test demonstrated no difference between right and left ears for each individual frequency. Spearman's test to analyse the effect on vessel number or minutes on bypass pump revealed no significant difference at 4-8 kHz (P = 0.550 for number of vessels and P = 0.276 for minutes on pump.)
Conclusion:
In this study, it was not possible to demonstrate any statistically significant deleterious effect of extra-corporeal (cardiopulmonary) bypass on hearing during coronary artery bypass grafting.
