Conti G, De Blasi R A, Lappa A, Ferretti A, Antonelli M, Bufi M, Gasparetto A
Istituto di Anestesiologia e Rianizmazione, University of Rome La Sapienza, Italy.
Intensive Care Med. 1994 Jul;20(6):421-4. doi: 10.1007/BF01710652.
To investigate the role played by the endotracheal tube (ETT) in the correct evaluation of respiratory system mechanics with the end inflation occlusion method during constant flow controlled mechanical ventilation.
General ICU, university of Rome "La Sapienza".
12 consecutive patients undergoing controlled mechanical ventilation.
We compared the values of minimal resistance of the respiratory system (i.e. airway resistance) (RRS min) obtained: i) subtracting the theoretical value of ETT resistance from the difference between P max and P1, measured on airway pressure tracings obtained from the distal end of the ETT; ii) directly measuring airway pressure 2 cm below the ETT, thus automatically excluding ETT resistance from the data. RESULTS. The values of RRS min obtained by measuring airway pressure below the ETT were significantly lower than those obtained by measuring airway pressure at the distal end of the ETT and subtracting the theoretical ETT resistance (4.5 +/- 2.8 versus 2.5 +/- 1.6 cm H2O/l/s, p < 0.01).
When precise measurements of ohmic resistances are required in mechanically ventilated patients, the measurements must be obtained from airways pressure data obtained at tracheal level. The "in vivo" positioning of ETT significantly increases the airflow resistance of the ETT.
探讨在恒流控制机械通气期间，气管内导管（ETT）在采用终末充气阻断法正确评估呼吸系统力学中所起的作用。
罗马“La Sapienza”大学综合重症监护病房。
12例接受控制机械通气的连续患者。
我们比较了通过以下方式获得的呼吸系统最小阻力值（即气道阻力）（RRS min）：i）从在ETT远端获得的气道压力描记图上测量的P max与P1之差中减去ETT阻力的理论值；ii）在ETT下方2 cm处直接测量气道压力，从而在数据中自动排除ETT阻力。结果。通过在ETT下方测量气道压力获得的RRS min值显著低于通过在ETT远端测量气道压力并减去理论ETT阻力获得的值（4.5±2.8与2.5±1.6 cm H2O/l/s，p<0.01）。
当需要对机械通气患者的欧姆阻力进行精确测量时，必须从气管水平获得的气道压力数据中进行测量。ETT的“体内”定位显著增加了ETT 的气流阻力。
