Influence of different classes of anesthetics on burst‐to‐burst variability of basal phrenic nerve discharge in adult in vivo rat

Abstract

The respiratory control system is highly dynamic, allowing for breath‐to‐breath adjustments to both physiological and pathological conditions. Ongoing work in our laboratory in the adult in vivo rat focuses on exploring the influence of different classes of anesthetics on various respiratory behaviors, including basal respiratory burst patterns. In the current study, we expand on this work by examining the influence of different classes of anesthetics on burst‐to‐burst variability of basal phrenic nerve discharge. Poincaré plot and coefficient of variation analyses were performed on 300 consecutive phrenic bursts obtained from urethane (U), inactin used alone (IN) or in combination with ketamine (IN‐K) or xylazine (IN‐X), sodium pentobarbital (P), ketamine in combination with xylazine (K‐X), propofol (PRO), and isoflurane (ISO) anesthetized rats; decerebrate rats were also studied. Our analyses suggest that different classes of anesthetics differentially influence the short‐term and long‐term variability of phrenic burst frequency and timing, and that typically used measures of variability may not fully capture long‐term patterns of variability. Supported by HL63175