Figure 3. Two consecutive periods of atracurium infusion (shaded areas) and recovery after neuromuscular blockade in one dog. Changes in peak-to-peak amplitude (V1) of the first evoked compound muscle action potentials, the relative shortening of the costal diaphragm from resting length (Delta L) during the supramaximal stimulation of the phrenic nerve, and the mean diaphragm action potential conduction velocity determined using the dip method (APCV^DIP) are expressed as a function of time. The segments of missing dip values represent the period of NMB when the animal was receiving ventilatory support.