Comparison of haemodynamic and respiratory variables at each of the four scans between babies with low and those with normal superior vena cava (SVC) flow
| 5 hour study | 12 hour study | 24 hour study | 48 hour study | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Low flow (n = 19) | Normal flow (n = 105) | p Value | Low flow (n = 22) | Normal flow (n = 100) | p Value | Low flow (n = 17) | Normal flow (n = 101) | p Value | Low flow (n = 6) | Normal flow (n = 109) | p Value | ||||
| Age at scan (hours) | 5.0 (1.0) | 5.0 (1.5) | 0.5 | 12.8 (2.3) | 12.9 (2.4) | 0.9 | 24 (1.1) | 24 (2.0) | 0.87 | 49 (3) | 48 (3) | 0.44 | |||
| SVC flow (ml/kg/min) | 23 (10–29) | 55 (31–143) | 27 (16–34) | 63 (34–134) | 30 (10–42) | 73 (42–150) | 42 (17–46) | 82 (47–158) | |||||||
| SVC velocity time integral (mm/s) | 55 (24–98) | 79 (31–98) | 61 (33–88) | 81 (40–160) | 62 (39–105) | 94 (42–176) | 51 (27–90) | 100 (48–226) | |||||||
| Mean SVC diameter (mm) | 2.0 (1.3–3.1) | 2.55 (1.6–4.1) | 1.8 (1.05–2.4) | 2.6 (1.7–3.7) | 1.85 (1.4–2.5) | 2.65 (1.8–3.8) | 2.1 (1.7–2.7) | 2.7 (1.5–3.7) | |||||||
| Ductal diameter (mm) | 2.1 (0.9–3) | 1.6 (0–3.5) | 0.0007 | 1.35 (0–2.8) | 1.1 (0–2.8) | 0.08 | 0.9 (0–2.2) | 0.8 (0–3.1) | 0.65 | 0 (0–2) | 0.4 (0–3) | 0.5 | |||
| Heart rate | 142 (125-192) | 144 (121–181) | 0.9 | 148 (130–170) | 144 (80–179) | 0.28 | 144 (129–163) | 144 (107–188) | 0.8 | 159 (153–170) | 148 (121–192) | 0.03 | |||
| Pco 2 | 38 (21–65) | 37.5 (18–62) | 0.9 | 35 (28–68) | 36.4 (23–64) | 0.98 | 34 (27–46) | 38 (27–67) | 0.008 | 40 (33–51) | 43 (31–64) | 0.6 | |||
| Fio 2 | 0.28 (0.21–1) | 0.25 (0.21–1) | 0.9 | 0.3 (0.21–0.5) | 0.25 (0.21–0.9) | 0.18 | 0.25 (0.21–1) | 0.24 (0.21–0.7) | 0.13 | 0.22 (0.21–0.3) | 0.24 (0.21–1) | 0.44 | |||
| Mean airway pressure (cm H2O) | 11 (8–19) | 9.4 (0–21) | 0.005 | 9.25 (6–13) | 7.8 (0–13) | 0.01 | 8.6 (6–11) | 7.3 (0–14) | 0.02 | 8.1 (6–10.5) | 7.7 (0–19) | 0.8 | |||
| Mean blood pressure (mm Hg) | 29 (20–39) | 31 (15–46) | 0.19 | 33 (22–47) | 33 (20–51) | 0.57 | 35 (23–42) | 36 (23–50) | 0.5 | 39 (30–42) | 38 (24–54) | 0.7 | |||
| Vascular resistance | 1.2 (0.9–3.1) | 0.54 (0.2–1) | 0.0001 | 1.15 (0.8–4.5) | 0.53 (0.2–1) | 0.0001 | 1.13 (0.7–2.9) | 0.5 (0.26–1.0) | 0.0001 | 0.99 (0.87–2.0) | 0.46 (0.2–0.98) | 0.0002 | |||
| % on dopamine | 0 | 0 | 13 | 3 | 0.07 | 18 | 2 | .02 | 0 | 2 | 0.12 | ||||
| % on dobutamine | 0 | 0 | 36 | 24 | 0.35 | 64 | 26 | .002 | 50 | 12 | 0.03 | ||||
Figures are given as median and range with the exception of age at scan, which is mean (SD).
Because SVC flow was the basis of the groupings, p values are not given for SVC parameters.