[The relationship between mouth pressure or tracheal pressure and esophagus pressure and diaphragmatic pressure].
OBJECTIVE
To investigate the relationship between mouth pressure (Pmo) or tracheal pressure (Ptr) and esophagus pressure (Pes) or transdiaphragmatic pressure.


METHODS
Seventeen patients were involved in the study. Maximal inspiratory pressure (MIP), maximal transdiaphragmatic pressure (Pdi(max)), maximal esophagus pressure (Pes(max)), twitch mouth pressure (TwPmo), twitch transdiaphragmatic pressure (TwPdi) and twitch esophagus pressure (TwPes) were measured before narcotization as a normal procedure for the abdominal operation and twitch tracheal pressure (TwPtr(nar)), twitch esophagus pressure (TwPes(nar)) and twitch transdiaphragmatic pressure (TwPdi(nar)) were dynamically monitored during narcotization.


RESULTS
(1) The correlation coefficient (r) values between Pdi(max) and MIP, TwPdi and TwPmo, TwPdi(nar) and TwPtr(nar), Pes(max) and MIP, TwPes and TwPmo, TwPes(nar) and TwPtr(nar) were 0.976 +/- 0.030, 0.816 +/- 0.155, 0.923 +/- 0.446, 0.981 +/- 0.185, 0.829 +/- 0.168 and 0.955 +/- 0.292, respectively. (2) The coefficient variation (CV) of MIP, Pes(max), Pdi(max), TwPmo, TwPes and TwPdi were (14.2 +/- 4.7)%, (15.2 +/- 4.3)%, (15.5 +/- 4.1)%, (30.4 +/- 15.9)%, (10.8 +/- 5.1)% and (9.9 +/- 4.0)%, respectively. The CV of TwPmo was the highest (compare with others, all P < 0.05) and that of TwPes and TwPdi was the lowest (compare with others, all P < 0.05). There was no significant difference among MIP, Pes(max) and Pdi(max) (P > 0.05). (3) The r value between the changing values of TwPtr(nar) and TwPdi(nar) or TwPes(nar) during narcotization were 0.839 or 0.894 (P = 0.000, respectively).


CONCLUSIONS
The measurement of MIP and TwPmo should be repeated and the highest value should be chosen in order to reduce the possibility of underestimating the function of diaphragm, which could be dynamically monitored by TwPtr(nar).
Zheng
Ze-guang
ZG
Guangzhou Institute of Respiratory Diseases, First Affiliated Hospital, Guangzhou Medical College, Guangzhou 510120, China.
Chen
Rong-chang
RC
Yu
Ge
G
Yang
Feng-quan
FQ
Zhang
Xing-jie
XJ
Li
Yi-min
YM
Zheng
Jing-ping
JP
Zhong
Nan-shan
NS