Blood pH and gases in fetuses in preterm labor with and without systemic inflammatory response syndrome

Figures & data

Table I.  Clinical and demographic characteristics of the study population.

	Delivery < 72 hours	Delivery > 72 hours	p
	n = 30	n = 60
Maternal age (years)	22 (18.7–26)	23 (20–27)	0.5
Gestational age at cordocentesis/amniocentesis (weeks)	28 (25–31.5)	31.7 (29–33)	0.01
Gestational age at delivery (weeks)	28.4 (25.1–32.2)	38.1 (37–39)	<0.001
Birthweight (g)	1100 (763.7–1685)	2973 (2615.2–3281.7)^a	<0.001

Values expressed as median (Inter quartile range) or number (percent).

Statistically significant, p < 0.05.

^an = 59.

Figure 1.  Fetal pH in patients who delivered within 72 hours after the cordocentesis and those who delivered more than 72 hours after the cordocentesis. There was no difference in the median fetal blood ΔpH between those who delivered within 72 hours after the cordocentesis and those who delivered 72 hours after the cordocentesis [median: −0.026, (IQR −0.4–−0.005) vs. median: −0.16, (IQR −0.042–−0.0005); p > 0.05].

Table II.  pH, gas analysis and IL-6 concentrations in the study population.

	Delivery < 72 hours	Delivery > 72 hours	p
	n = 30	n = 60
Fetal pH	7.38 (7.35–7.40)	7.38 (7.36–7.40)	0.7
ΔFetal pH	−0.026 (−0.400 to −0.005)	−0.016 (−0.042 to −0.0005)	0.8
PaO2 (mmHg)	40.3 (27.3–49.1)	44.5 (33.4–52.9)	0.2
ΔPaO2 (mmHg)	0.25 (−9.57–9.12)	5.97 (−3.21–16.2)	0.06
Base excess (mEq/L)	−2.4 (−3.3 to −1)	−2.6 (−4.2 to −1.3)^a	0.7
Fetal IL-6 (pg/mL)	26.7 (4.6–160.5)^b	5.6 (4–8.2)^c	0.01
Amniotic fluid IL-6 (pg/mL)	35,700 (9724.5–61,400)^d	725.8 (353.3–1300)^e	<0.001

Values expressed as median (Inter quartile range) or number (percent).

Statistically significant, p < 0.05.

^an = 58.

^bn = 18.

^cn = 39.

^dn = 14.

^en = 35.

Figure 2.  Fetal PaO₂ in patients who delivered within 72 hours after the cordocentesis and those who delivered more than 72 hours after the cordocentesis. There was no difference in the median ΔPaO₂ between those who delivered within 72 hours after the cordocentesis and those who delivered 72 hours after the cordocentesis [median: 0.25 mmHg, (IQR −9.57 to –9.12) vs. median: 5.9 mmHg, (IQR −3.21 to –16.2); p > 0.05].

Figure 3.  Fetal base excess in patients who delivered before 72 hours after the cordocentesis and those who delivered more than 72 hours after the cordocentesis. There was no difference in the median fetal base excess between those who delivered before 72 hours of the cordocentesis and those who delivered after 72 hours of the cordocentesis [median: −2.4 mEq/L, (IQR −3.3–−1) vs. median: −2.6 mEq/L, (IQR −4.2–−1.3); p > 0.05].

Table III.  Clinical and demographic characteristics of the study population of fetuses with and without FIRS.

	Fetuses with FIRS	Fetuses without FIRS	p
	n = 16	n = 41
Maternal age (years)	23 (19–25)	22 (20–27)	0.5
Gestational age at cordocentesis/amniocentesis (weeks)	26.5 (25–30.9)	32.1 (29.5–33.1)	<0.001
Gestational age at delivery (weeks)	27.2 (24.5–35.2)	37.5 (34.7–39)	<0.001
Interval to delivery (days)	2 (1–29)	41 (22–57.5)	0.002
Birthweight (g)	1058 (720–2629.7)	2807 (2240–3105)	0.002

Values expressed as median (Inter quartile range) or number (percent).

Statistically significant, p < 0.05.

Figure 4.  Fetal pH in fetuses with and without FIRS. There was no difference in the median fetal blood pH between fetuses with and without FIRS [median: 7.38, (IQR 7.36–7.39) vs. median: 7.39, (IQR 7.35–7.40); p > 0.05].

Figure 5.  Fetal PaO₂ in fetuses with and without FIRS. There was no difference in the median fetal PaO₂ between fetuses with FIRS and without FIRS [median: 48.4 mmHg, (IQR 39.7–56.8) vs. median: 43 mmHg, (IQR 32.1–50.6); p > 0.05].

Figure 6.  Fetal base excess in fetuses with and without FIRS. There was no difference in the median fetal base excess between fetuses with and without FIRS [median: −3.3 mEq/L, (IQR −5.3–−1.8) vs. median: −2.3 mEq/L, (IQR −4.1–−1.4); p > 0.05].

Table IV.  pH, PaO₂, base excess and IL-6 concentrations in the study population of fetuses with and without FIRS.

	Fetuses with FIRS	Fetuses without FIRS	p
	n = 16	n = 41
Fetal pH	7.38 (7.36–7.39)	7.39 (7.35–7.40)	0.6
ΔFetal pH	−0.028 (−0.033–−0.020)	−0.012 (−0.040–0.0008)	0.3
PaO2 (mmHg)	48.4 (39.7–56.8)	43 (32.1–50.6)	0.8
ΔPaO2 (mmHg)	5.2 (−1.2–18)	7.8 (−5.5–14.2)	0.5
Base excess (mEq/L)	−3.3 (−5.3–−1.8)	−2.3 (−4.1–−1.4)^a	0.2
Fetal IL-6 (pg/mL)	114.8 (18.1–190.8)	5 (3.2–6.3)	<0.001
Amniotic fluid IL-6 (pg/mL)	22,030 (659.9–61,400)	841.1 (394.3–1810.8)	0.009

Values expressed as median (Inter quartile range) or number (percent).

Statistically significant, p < 0.05.

^an = 39.