Respiratory system mechanics in guinea pigs after acute hemorrhage: Role of adrenergic stimulation

We evaluated the effects of acute blood loss on the respiratory mechanics of guinea pigs. We measured respiratory system elastance (Ers) and resistance (Rrsmax) using the end-inflation occlusion method. RrSmax was partitioned into its homogeneous component (Rrsmin) and that due to the unevenness within the respiratory system (Rrsu). Respiratory mechanics were studied both before and immediately after bleeding in eight animals. Another eight guinea pigs had received propranolol previously and were also submitted to hemorrhage. Propranolol-treated animals showed higher control values of Rrsmax (p