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Published on: May 19, 2021
Impact of isoproterenol infusion on BIS and metabolic values in pediatric patients undergoing electrophysiology
Nischal K Gautam1, Muhammad B Rafique1, Mohammed T Numan2
1Department of Anesthesiology, Division of Pediatric Cardiac Anesthesia, The University of Texas Medical School at Houston, Houston, TX 770025, USA.
Insights
Isoproterenol infusion in pediatric patients undergoing anesthesia increases Bispectral Index (BIS) values, end-tidal CO2 (ETCO2), and lactate levels. Careful anesthetic titration and BIS monitoring are recommended during these procedures.
Area of Science:
- Anesthesiology
- Pediatric Critical Care
- Clinical Pharmacology
Background:
- Isoproterenol is used in pediatric electrophysiology procedures.
- Understanding its effects on anesthetic depth and metabolism is crucial.
Purpose of the Study:
- To investigate changes in Bispectral Index (BIS) and metabolic parameters during isoproterenol infusion in pediatric patients.
Main Methods:
- Retrospective analysis of pediatric patients undergoing general anesthesia for electrophysiology procedures.
- Collected data included BIS, anesthetics, hemodynamics, respiratory parameters (ETCO2), and blood gases.
- Parameters were compared before and during isoproterenol infusion.
Main Results:
- BIS values significantly increased (P < 0.001) during isoproterenol infusion.
- Significant increases in end-tidal CO2 (ETCO2), PaCO2, and lactate were observed (P < 0.01).
- Ventilation strategies adapted, with increased ETCO2 in mechanically ventilated patients and increased minute ventilation in spontaneously breathing patients.
Conclusions:
- Isoproterenol increases metabolic, respiratory, and BIS values in pediatric patients under general anesthesia.
- Recommend BIS monitoring, close ETCO2 surveillance, and careful anesthetic titration during isoproterenol infusions for pediatric electrophysiologic procedures.
Study Objective:
To study changes in BIS values and metabolic parameters during an infusion of isoproterenol in pediatric patients.
Design:
Retrospective study approved By Committee For The Protection Of Human Subjects at University Of Texas Medical School at Houston.
Setting:
University-affiliated children's hospital.
Measurements:
The records of pediatric patients undergoing general anesthesia for electrophysiology procedures were analyzed. Electronic data collected included Bispectral Index (BIS) values, anesthetics (eg, opioids, expired concentration of inhaled anesthetics, muscle relaxants), hemodynamic values (ie, heart rate, invasive blood pressure), respiratory parameters [ie, tidal volume, respiratory rate, end-tidal CO2 (ETCO2)], and routine arterial blood gases. These parameters were analyzed 10 minutes prior to the start of the isoproterenol infusion (T-pre) and 10 minutes after isoproterenol had reduced the cardiac cycle length by 20% (T-infusion).
Main Results:
Of the 29 records that were screened, 22 met the above criteria (mean age 13 ± 5 yrs). BIS values increased by an average of 8 (33 ± 8 to 41 ± 10; P < 0.001) during the isoproterenol infusion. Statistically significant increases in ETCO2 (median 33 - 36 mmHg; P = 0.01), PaCO2 (35 - 38 mmHg; P = 0.002), and lactate (1.1 -1.5 mg/dL; P < 0.001) occurred with infusion of isoproterenol. Patients undergoing controlled mechanical ventilation showed an increase in ETCO2 (mean 34 ± 6 mmHg to 37 ± 5 mmHg; P = 0.001) whereas those breathing spontaneously had an increase in minute ventilation (average increase 111 ± 30 mL/kg).
Conclusions:
Isoproterenol increases metabolic, respiratory, and BIS values in pediatric patients during general anesthesia. We recommend the use of BIS, close monitoring of ETCO2, and careful titration of anesthetics during isoproterenol infusion, especially when lighter planes of general anesthesia are requested for pediatric electrophysiologic procedures.

