Thyrault M, Teboul J L, Richard C, Coirault C, Lecarpentier Y, Chemla D
Service de Réanimation Médicale and Service de Physiologie Cardio-Respiratoire, Université de Paris XI, Hôpital de Bicêtre, Le Kremlin-Bicêtre, France.
Intensive Care Med. 1998 Jan;24(1):77-80. doi: 10.1007/s001340050519.
It has been recently shown that there is a match between dicrotic notch and mean pulmonary artery (PA) pressures in spontaneously breathing patients studied by means of high-fidelity pressure catheters. The aim of the study was to analyze the relation between mean PA pressure and PA pressure at the incisura by using a Swan-Ganz catheter in critically ill, mechanically ventilated patients.
Fluid-filled PA pressures were obtained over four ventilatory cycles in 32 consecutive, mechanically ventilated patients in the intensive care unit. We measured mean PA pressure and dicrotic notch pressure. We also calculated the widely used approximation of mean PA pressure (mean PAPapprox = diastolic + 1/3 pulse pressure). Cardiac output was measured in triplicate by using the thermodilution technique. Dicrotic notch was clearly identified in 30 of 32 patients. Mean PA pressure (32.1 +/- 10.2 mm Hg) and PA dicrotic notch pressure (31.8 +/- 10.4 mm Hg) were linearly related (r = 0.989, p < 0.001). Agreement between dicrotic notch and mean PA pressures was suggested (mean difference +/- SD = -0.3 +/- 1.5 mm Hg). Similar agreement was found between mean PAPapprox and mean PA pressure (mean difference +/- SD = -0.7 +/- 0.8 mm Hg; p = 0.20).
By using a Swan-Ganz catheter we found that dicrotic notch pressure equalled mean PA pressure in the critically ill, mechanically ventilated patients studied. This indicated that right-sided ejection was completed at a PA pressure equal to mean PA pressure in these patients.
最近有研究表明，通过高保真压力导管对自主呼吸患者进行研究时，重搏波切迹与平均肺动脉（PA）压之间存在匹配关系。本研究的目的是在危重症机械通气患者中使用Swan - Ganz导管分析平均PA压与切迹处PA压之间的关系。
在重症监护病房对32例连续的机械通气患者进行了四个通气周期的充液式PA压测量。我们测量了平均PA压和重搏波切迹压。我们还计算了广泛使用的平均PA压近似值（平均PAPapprox = 舒张压 + 1/3脉压）。采用热稀释技术对心输出量进行了三次测量。32例患者中有30例可清晰识别出重搏波切迹。平均PA压（32.1±10.2 mmHg）与PA重搏波切迹压（31.8±10.4 mmHg）呈线性相关（r = 0.989，p < 0.001）。提示重搏波切迹与平均PA压之间具有一致性（平均差值±标准差 = -0.3±1.5 mmHg）。平均PAPapprox与平均PA压之间也发现了类似的一致性（平均差值±标准差 = -0.7±0.8 mmHg；p = 0.20）。
通过使用Swan - Ganz导管，我们发现在所研究的危重症机械通气患者中，重搏波切迹压等于平均PA压。这表明在这些患者中，右心室射血在PA压等于平均PA压时完成。
