Seghaye M C, Duchateau J, Bruniaux J, Demontoux S, Détruit H, Bosson C, Lecronier G, Mokhfi E, Serraf A, Planché C
Department of Pediatric Intensive Care, Centre Chirurgical Marie-Lannelongue, Paris, France.
Crit Care Med. 1997 Jun;25(6):1063-70. doi: 10.1097/00003246-199706000-00026.
To examine whether preoperative heart failure and cardiac surgery influence nitric oxide production and atrial natriuretic peptide (ANP) biological activity in infants and whether nitric oxide and ANP participate in the control of postoperative pulmonary vascular tone.
Prospective, clinical study.
Tertiary pediatric cardiac intensive care unit in a referral cardiosurgical center.
Nineteen infants (median age 4 months) undergoing cardiac surgery: 13 infants with ventricular or atrioventricular septal defect associated with heart failure and pulmonary hypertension (group 1); and six infants with tetralogy of Fallot, without heart failure (group 2).
Blood samples obtained from indwelling catheters or bypass circuit outlets.
Nitrite and nitrate blood concentrations (as a marker for nitric oxide synthesis) and the molar ratio of cyclic guanosine 3',5'-monophosphate (cGMP) to ANP (as a marker for ANP biological activity) were determined before, during, and up to 24 hrs after cardiopulmonary bypass (CPB). In group 1 patients, these biological parameters were related to postoperative pulmonary arterial pressure. Preoperative nitrite and nitrate concentrations were higher in group 1 patients than in group 2 patients (p < .02), and this difference persisted during CPB. Nitrite and nitrate concentrations 24 hrs postoperatively were lower than preoperative values in group 1 patients (p < .05) and were unchanged in group 2 patients. An inverse correlation was observed postoperatively between nitrite and nitrate concentrations and systolic pulmonary arterial pressure (r2 = 0.4, p < .05). Group 1 patients had a lower preoperative cGMP/ANP ratio than group 2 patients (p < .05), despite higher ANP levels (p < .005). The cGMP/ANP ratio decreased during CPB in both groups (p < .0001), and in group 2 patients, cGMP and ANP values remained below preoperative values < or = 24 hrs postoperatively. A correlation was observed between ANP levels and systolic pulmonary arterial pressure 2 and 4 hrs postoperatively (r2 = .4, p < .05, respectively), but no correlation was observed between ANP biological activity and postoperative pulmonary arterial pressure.
Infants with heart failure and pulmonary hypertension have increased nitric oxide synthesis and decreased ANP biological activity; both phenomena may be involved in the pathophysiology of this clinical condition. CPB has no detectable effect on nitric oxide production but does decrease ANP biological activity. In patients with preoperative heart failure and pulmonary hypertension, endogenous nitric oxide appears to play a role in the control of postoperative pulmonary vascular tone.
探讨术前心力衰竭和心脏手术对婴儿一氧化氮生成及心钠素（ANP）生物活性的影响，以及一氧化氮和ANP是否参与术后肺血管张力的调控。
前瞻性临床研究。
一家转诊心脏外科中心的三级儿科心脏重症监护病房。
19例接受心脏手术的婴儿（中位年龄4个月）：13例患有室间隔或房室间隔缺损并伴有心力衰竭和肺动脉高压的婴儿（第1组）；6例法洛四联症且无心力衰竭的婴儿（第2组）。
从留置导管或体外循环出口采集血样。
测定体外循环（CPB）前、期间及术后24小时内亚硝酸盐和硝酸盐血浓度（作为一氧化氮合成的标志物）以及环磷酸鸟苷（cGMP）与ANP的摩尔比（作为ANP生物活性的标志物）。在第1组患者中，这些生物学参数与术后肺动脉压相关。第1组患者术前亚硝酸盐和硝酸盐浓度高于第2组患者（p <.02），且在CPB期间这种差异持续存在。第1组患者术后24小时亚硝酸盐和硝酸盐浓度低于术前值（p <.05），而第2组患者则无变化。术后亚硝酸盐和硝酸盐浓度与收缩期肺动脉压呈负相关（r2 = 0.4，p <.05）。第1组患者术前cGMP/ANP比值低于第2组患者（p <.05），尽管其ANP水平较高（p <.005）。两组患者在CPB期间cGMP/ANP比值均下降（p <.0001），且在第2组患者中，术后≤24小时cGMP和ANP值仍低于术前值。术后2小时和4小时ANP水平与收缩期肺动脉压之间存在相关性（r2分别为.4，p <.05），但ANP生物活性与术后肺动脉压之间未观察到相关性。
患有心力衰竭和肺动脉高压的婴儿一氧化氮合成增加且ANP生物活性降低；这两种现象可能均参与了该临床病症的病理生理过程。CPB对一氧化氮生成无明显影响，但会降低ANP生物活性。在术前患有心力衰竭和肺动脉高压的患者中，内源性一氧化氮似乎在术后肺血管张力的调控中发挥作用。
