Respiratory mechanics after chronic diethylcarbamazine

Abstract

This study was performed to evaluate the role of diethylcarbamazine (DEC), the drug of choice for treating Lymphatic Filariasis and Tropical Pulmonary Eosinophilia, on respiratory mechanics of higid rats. Thus, during 30 days two groups of six rats each received intraperitoneally either isotonic saline solution, or 12 mg/kg per day of DEC. Thereafter, they were sedated, anesthetized, paralysed and mechanical ventilation followed. After airway occlusion at end inspiration, respiratory system, pulmonary and chest wall resistive pressures (ΔP 1,rs, ΔP 1,L, and ΔP 1,w, respectively) and viscoelastic/inhomogeneous pressures (ΔP 2,rs, ΔP 2,L and ΔP 2,w, respectively) were determined in each group. Total Δ pressures (ΔPtot) were calculated as the sum of ΔP 1 and ΔP 2, yielding the values of ΔP tot,rs, ΔP tot,L, and ΔP tot,w, respectively. Respiratory system, lung and chest wall static (E st,rs, E st,L, and E st,w, respectively) and dynamic elastances (E dyn,rs, E dyn,L, and E dyn,w, respectively), and the corresponding Δ elastances (calculated as E dyn−E st) were also obtained. DEC therapy significantly decreased ΔP tot,rs, ΔP tot,L, ΔP 2,rs, ΔP 2,L, E st,rs, E st,L, ΔE rs and ΔE L in relation to the respective control values. It can be concluded that DEC decreases respiratory system impedance, being potentially useful for allowing airway dilation at the lung periphery.