TY - JOUR
T1 - Effects of Ketamine Infusion on Breathing and Encephalography in Spontaneously Breathing ICU Patients
AU - Suleiman, Aiman
AU - Santer, Peter
AU - Munoz-Acuna, Ronny
AU - Hammer, Maximilian
AU - Schaefer, Maximilian S.
AU - Wachtendorf, Luca J.
AU - Rumyantsev, Sandra
AU - Berra, Lorenzo
AU - Chamadia, Shubham
AU - Johnson-Akeju, Oluwaseun
AU - Baedorf-Kassis, Elias N.
AU - Eikermann, Matthias
N1 - Publisher Copyright:
© The Author(s) 2022.
PY - 2023/3
Y1 - 2023/3
N2 - Background: Preclinical studies suggest that ketamine stimulates breathing. We investigated whether adding a ketamine infusion at low and high doses to propofol sedation improves inspiratory flow and enhances sedation in spontaneously breathing critically ill patients. Methods: In this prospective interventional study, twelve intubated, spontaneously breathing patients received ketamine infusions at 5 mcg/kg/min, followed by 10 mcg/kg/min for 1 h each. Airway flow, pressure, and esophageal pressure were recorded during a spontaneous breathing trial (SBT) at baseline, and during the SBT conducted at the end of each ketamine infusion regimen. SBT consisted of one-minute breathing with zero end-expiratory pressure and no pressure support. Changes in inspiratory flow at the pre-specified time points were assessed as the primary outcome. Ketamine-induced change in beta-gamma electroencephalogram power was the key secondary endpoint. We also analyzed changes in other ventilatory parameters respiratory timing, and resistive and elastic inspiratory work of breathing. Results: Ketamine infusion of 5 and 10 mcg/kg/min increased inspiratory flow (median, IQR) from 0.36 (0.29-0.46) L/s at baseline to 0.47 (0.32-0.57) L/s and 0.44 (0.33-0.58) L/s, respectively (p =.013). Resistive work of breathing decreased from 0.4 (0.1-0.6) J/l at baseline to 0.2 (0.1-0.3) J/l after ketamine 10 mcg/kg/min (p =.042), while elastic work of breathing remained unchanged. Electroencephalogram beta-gamma power (19-44 Hz) increased compared to baseline (p <.01). Conclusions: In intubated, spontaneously breathing patients receiving a constant rate of propofol, ketamine increased inspiratory flow, reduced inspiratory work of breathing, and was associated with an “activated” electroencephalographic pattern. These characteristics might facilitate weaning from mechanical ventilation.
AB - Background: Preclinical studies suggest that ketamine stimulates breathing. We investigated whether adding a ketamine infusion at low and high doses to propofol sedation improves inspiratory flow and enhances sedation in spontaneously breathing critically ill patients. Methods: In this prospective interventional study, twelve intubated, spontaneously breathing patients received ketamine infusions at 5 mcg/kg/min, followed by 10 mcg/kg/min for 1 h each. Airway flow, pressure, and esophageal pressure were recorded during a spontaneous breathing trial (SBT) at baseline, and during the SBT conducted at the end of each ketamine infusion regimen. SBT consisted of one-minute breathing with zero end-expiratory pressure and no pressure support. Changes in inspiratory flow at the pre-specified time points were assessed as the primary outcome. Ketamine-induced change in beta-gamma electroencephalogram power was the key secondary endpoint. We also analyzed changes in other ventilatory parameters respiratory timing, and resistive and elastic inspiratory work of breathing. Results: Ketamine infusion of 5 and 10 mcg/kg/min increased inspiratory flow (median, IQR) from 0.36 (0.29-0.46) L/s at baseline to 0.47 (0.32-0.57) L/s and 0.44 (0.33-0.58) L/s, respectively (p =.013). Resistive work of breathing decreased from 0.4 (0.1-0.6) J/l at baseline to 0.2 (0.1-0.3) J/l after ketamine 10 mcg/kg/min (p =.042), while elastic work of breathing remained unchanged. Electroencephalogram beta-gamma power (19-44 Hz) increased compared to baseline (p <.01). Conclusions: In intubated, spontaneously breathing patients receiving a constant rate of propofol, ketamine increased inspiratory flow, reduced inspiratory work of breathing, and was associated with an “activated” electroencephalographic pattern. These characteristics might facilitate weaning from mechanical ventilation.
KW - ICU sedation
KW - Ketamine infusion
KW - brain activity
KW - critical care ventilation
KW - inspiratory flow
KW - mechanical ventilation
KW - spontaneous breathing trial
KW - weaning from ventilator
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U2 - 10.1177/08850666221119716
DO - 10.1177/08850666221119716
M3 - Article
C2 - 35934953
AN - SCOPUS:85135738024
SN - 0885-0666
VL - 38
SP - 299
EP - 306
JO - Journal of Intensive Care Medicine
JF - Journal of Intensive Care Medicine
IS - 3
ER -