[A significance of measurement of breathing nervous regulation, respiratory resistance and spirometry in clinical toxicology - retrospective review].

UNLABELLED: The exogenous central nervous system depressants such opioides, alcohol and carbon monoxide may affect nervous respiratory regulation and lead to disturbances in respiratory system efficiency. The aim of this study was to evaluate the breathing nervous regulation and ventilatory efficiency in patients treated in Clinical Toxicology, UJCM in Krakow in the period 1994- 2000.

METHODS

There were 385 persons under examination: 144 alcohol abusers and 70 opiate abusers (group I), 91 persons treated because of acute carbon monoxide poisoning (group II) and 80 healthy persons - control group. The examinations performed before and after treatment included measurements of respiratory pattern parameters, occlusion pressure and evaluation of ventilatory efficiency determined on the basis of “flow-volume” loop results, spirometry and the measurements of respiratory tract resistance.

RESULTS

The central respiratory drive (VT/T(in) index) and the parasympathetic control of breathing cycle (T(in)/ T(tot) index) were similar in alcohol and opiate abusers in the initial examination but in abusers classified to methadone maintenance treatment programme the VT/T(in) index was elevated. After treatment the values of both indices were similar. In the group of acute CO poisoned patients the disturbances in breathing regulation were connected with increased value of the VT/Tin parameter and the diminished of T(in)/T(tot) value. After treatment in the slightly CO poisoned patients the both respiratory pattern components were comparable to the healthy control group but in the moderately and severely poisoned group the VT/T(in) index was elevated and the T(in)/T(tot) index was lessened compared to the controls. The values of respiratory resistance were higher than upper level of normal values (except participants of methadone programme). The bronchial obturation was most often stated disturbance in respiratory system efficiency, especially in alcohol abusers. Ventilatory parameters in moderate and severe CO poisoned were significantly lower than in the slightly poisoned patients.

CONCLUSION

Presented methods of evaluation of respiratory system efficiency and nervous breathing regulation are of special value and should be implemented in clinical toxicology as essential to diagnosis and monitoring, especially in case of alcohol and drug dependent patients and in patients poisoned with central nervous system depressants.