Improved determination of static compliance by automated single volume steps in ventilated patients

A new method for determination the static compliance of the respiratory system is described ("static compliance by automated single steps"--SCASS). In 12 ventilated patients pressure/volume (P/V) curves were determined by automated repetitive occlusion (6 s) at single volume steps and comp...

Full description

Saved in:
Bibliographic Details
Published in:Intensive care medicine 1991-01, Vol.17 (2), p.108-114
Main Authors: SYDOW, M, BURCHARDI, H, ZINSERLING, J, ISCHE, H, CROZIER, T. A, WEYLAND, W
Format: Article
Language:English
Subjects:
Adult
Aged
Aged, 80 and over
Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy
Biological and medical sciences
Emergency and intensive respiratory care
Female
Humans
Humidity
Intensive care medicine
Lung Compliance
Male
Medical sciences
Middle Aged
Pressure
Pulmonary Gas Exchange
Respiration, Artificial - methods
Respiratory Insufficiency - physiopathology
Respiratory Mechanics
Syringes
Temperature
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A new method for determination the static compliance of the respiratory system is described ("static compliance by automated single steps"--SCASS). In 12 ventilated patients pressure/volume (P/V) curves were determined by automated repetitive occlusion (6 s) at single volume steps and compared to the conventional syringe method (SM). All measurements were corrected for effects of temperature, humidity and pressure (THP). SM was found to be significantly influenced by intrapulmonary gas exchange causing an effective mean volume deficit of 217.4 +/- 65.7 ml (BTPS) at the end of the deflation. In contrast to that, the short duration of occlusion in SCASS minimize the gas exchange effects. The methodical differences between both methods result in overestimation of the inflation compliance in the uncorrected SM (SMuncorr: 83.4 +/- 12.6; SCASS: 76.0 +/- 11.9 ml/cmH2O. p less than 0.01) and underestimation of the deflation compliance resp. (SMuncorr: 58.3 +/- 7.5; SCASS: 79.1 +/- 15.0 ml/cmH2O. p less than 0.005). In contrast to the P/V curves by SM no significant hysteresis was found by SCASS. Gas exchange seems to be the main reason for the hysteresis. Even after correcting gas exchange and THP effects a significant hysteresis remained. The SCASS method avoids these problems and allows furthermore an accurate checking of leaks.
ISSN:0342-4642
1432-1238
DOI:10.1007/BF01691433