[Clinical monitoring of myocardial injury in neonates with intrauterine distress].

Objective: To investigate whether no asphyxia neonates with intrauterine distress are complicated with myocardial injury and determine the sensitive biochemical diagnostic parameters.

Methods: A total of 89 neonates born in the First Affiliated Hospital of Sun Yat-sen University from July 2009 to December 2009 were enrolled. Fifty-three fetal distress cases with Apgar score > 7 at 1 and 5 minutes were enrolled in the study group; while the rest 36 healthy neonates, whose Apgar score = 10 at 1 and 5 minutes, were the control group. Umbilical artery blood samples of all cases were collected for blood gas analysis and biochemical measurement.

Results: (1) pH (7.23 ± 0.07) and BE [(-4.8 ± 3.0) mmol/L] in the study group were significantly lower than pH (7.31 ± 0.03) and BE [(-2.1 ± 1.5) mmol/L ] in the control group(P < 0.05). The lactic acid of study group [(5.2 ± 2.3) mmol/L] was higher than that of the control group [(2.3 ± 1.1) mmol/L], and the difference was significant (P < 0.01). However, there was no significant difference between the two groups in PaO2 [(16.2 ± 7.9) mm Hg (1 mm Hg = 0.133 kPa) vs. (17.5 ± 6.7) mm Hg] and PaCO2 [(54.0 ± 11.2) mm Hg vs. (48.5 ± 5.4) mm Hg; P > 0.05]. (2) The level of CK-MB in neonates with fetal distress[ (48 ± 59) U/L] was significantly higher than that of healthy neonates [(36 ± 27) U/L]. However, no significant difference was found in CK [(194 ± 73) U/L vs. (162 ± 95) U/L] and BNP levels [(519 ± 309) ng/L vs. (481 ± 216) ng/L; P > 0.05]. (3) Spearman rank correlation analysis showed that CK-MB level was negatively correlated with pH (r = -0.296, P < 0.05) and BE (r = -0.318, P < 0.05) of umbilical artery blood, while BNP level was positively correlated with umbilical lactic acid (r = 0.278, P < 0.05). No correlation was found between other parameters (P > 0.05).

Conclusions: Intrauterine distress without neonatal asphyxia had effect on fetal myocardial injury. CK-MB can be used as a sensitive parameter for monitoring the development of myocardial injury. The severity of myocardial injury was related to fetal acidosis.