[Effects of fluid resuscitation on myocardial injury in patients with severe sepsis and septic shock].

OBJECTIVE: To observe the influence of fluid resuscitation on patients suffered from myocardial injury with severe sepsis and septic shock, and to evaluate the markers of myocardial injury during fluid resuscitation.

METHODS: Acute physiology and chronic health evaluation II (APACHE II) score of 78 patients with severe sepsis and septic shock induced by combined injuries was 18-35. Serum cardiac troponin I (cTnI), N-terminal-ventricular natriuretic peptide precursor (NT-proBNP) and the hemodynamic parameters were recorded before, 3 days, and 5 days after treatment, and correlative analysis was conducted.

RESULTS: Serum cTnI was increased in 62.8% (49/78) patients with severe sepsis and septic shock, and in 73.5% of patients (36/49) the increase was greater than 2-fold of the borderline value, and in 30.6% of patients (15/49) was greater than 4-fold of the borderline value. The patients with elevated serum NT-proBNP at admission accounted for 46.2% (36/78), and after fluid resuscitation treatment, patients with continuously rising value accounted for 74.4% (58/78). The serum cTnI, NT-proBNP, pulmonary arterial wedge pressure (PAWP) and cardiac index (CI) after treatment in survival group (55 cases) were obviously improved, and changes in them in non-survival group (23 cases) was not obvious. The serum cTnI (μg/L) and NT-proBNP (ng/L) levels in the non-survival group were distinctly higher than those of the survival group (cTnI 3 days: 2.09 ± 1.00 vs. 1.57 ± 0.93, 5 days: 1.78 ± 0.67 vs. 0.72 ± 0.51; NT-proBNP 3 days: 3.52 ± 0.73 vs. 3.16 ± 0.65, 5 days: 3.21 ± 0.66 vs. 2.66 ± 0.58), and CI [ml·s(-1)·m(-2)] was obviously lower than that of the survival group (3 days: 57.6 ± 6.2 vs. 68.3 ± 5.6, 5 days: 40.5 ± 4.7 vs. 80.7 ± 6.8, all P < 0.05). The cTnI level (μg/L) of 46 patients whose fluid resuscitation achieved the target was lower than that of the 32 cases without achieving the target (1.16 ± 0.62 vs. 1.97 ± 0.76, P < 0.05), and the CI [ml·s(-1)·m(-2)] was obviously increased (61.2 ± 6.4 vs. 49.3 ± 6.1, P < 0.05). The results suggested that whether the fluid resuscitation achieved the target or not was not related to changes in serum NT-proBNP and PAWP. A positive correlation was found between serum cTnI and NT-proBNP (r = 0.865, Y = 2.069 + 0.695X, P < 0.01), also between NT-proBNP and PAWP (r = 0.762, Y = 1.125 + 4.929X, P < 0.01), and a negative correlation was found between cTnI and CI (r = -0.891, Y = 50.623 - 6.114X, P < 0.01).

CONCLUSIONS: There is an obvious myocardial injury in the patient with severe sepsis and septic shock, and fluid resuscitation can improve the myocardial injury; the serum levels of cTnI and NT-proBNP are related to the prognosis of patients, but the significance of NT-proBNP guiding the fluid resuscitation can not be ascertained.