Serna-Muñoz R, Jaramillo-Magaña JJ

Language: Spanish
References: 87
Page: 176-186
PDF size: 2204.69 Kb.

ABSTRACT

Minimum alveolar concentration (MAC) is a useful population metric of inhaled anesthetic potency, yet it primarily predicts immobility and does not ensure unconsciousness. Real intraoperative physiology challenges end-tidal assumptions: ventilation-perfusion heterogeneity, shunt, dead space, and hemodynamic variability can decouple end-tidal concentration from arterial and brain partial pressures, leading to under- or overestimation of cortical effect. In balanced anesthesia, opioids and neuromuscular blockade further dissociate immobility from hypnosis, increasing the risk of inadequate cortical suppression despite apparent clinical stability. Electroencephalography (EEG), both raw and processed, offers continuous monitoring of cortical dynamics and supports effect-guided titration. Avoiding iatrogenic burst suppression is clinically relevant given its association with adverse outcomes. This manuscript argues for reframing anesthetic goals beyond MAC by integrating MAC-based context, lung–blood–brain pharmacokinetics, and EEG-derived indices and spectral metrics to individualize dosing, minimize extremes of exposure, and improve patient safety across heterogeneous surgical populations.

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