Summary of changes in blood pressure, nasal temperature, haemoglobin concentration, cerebral FOE, and oxidised cytochrome oxidase concentration in the different groups. FOE is expressed as mean (SD), other variables are expressed as median (range)
| Profound hypothermia | Moderate hypothermia | Mild hypothermia | |||||
|---|---|---|---|---|---|---|---|
|
Continuous flow (n = 7) |
Circulatory arrest (n = 8) |
Continuous flow (n = 8) |
Circulatory arrest (n = 1) |
Continuous flow (n = 6) | |||
| Cerebral FOE | |||||||
| Before bypass | 0.371 (0.18) | 0.384 (0.09) | 0.362 (0.15) | 0.29 | 0.340 (0.05) | ||
| Cooling | 0.412 (0.17) | 0.400 (0.13) | 0.368 (0.10) | 0.44 | 0.440 (0.08) | ||
| Cold bypass | 0.350 (0.02) | 0.415 (0.10) | 0.367 (0.14) | 0.25 | 0.390 (0.03) | ||
| Rewarming | 0.463 (0.10) | 0.356 (0.08) | 0.455 (0.09) | 0.32 | 0.440 (0.08) | ||
| After bypass | 0.417 (0.16) | 0.353 (0.13) | 0.388 (0.15) | 0.42 | 0.380 (0.06) | ||
| Systolic blood pressure (mm Hg) | |||||||
| Before bypass | 89 (76–95) | 79.5 (54–89) | 96 (85–112) | 110 | 85 (79–103) | ||
| Cooling | 39 (33–102) | 47 (37–140) | 51 (36–103) | 51 | 61 (43–123) | ||
| Cold bypass | 49.5 (20–71) | 70 (66–72) | 45 (13–86) | 33 | 87 (80–151) | ||
| Rewarming | 55 (46–63) | 60 (45–118) | 66 (48–98) | 56 | 73 (49–134) | ||
| After bypass | 68 (64–92) | 77 (66–97) | 98 (74–116) | 70 | 99 (85–108) | ||
| Haemoglobin (g/dl) | |||||||
| Before bypass | 11.4 (10.3–18.7) | 12.6 (10.3–17.4) | 12.9 (10.5–14.6) | 16.3 | 12.9 (11.7–13.4) | ||
| Cooling | 7.5 (6.8–13) | 8.9 (5.6–10.7) | 9.3 (6.3–11.7) | 10.7 | 9.9 (8.1–12.2) | ||
| Cold bypass | 10.5 (8.9–12) | 10 (8.6–13.5) | 9.8 (5.7–11.7) | 10.0 | 9.7 (8.1–12.2) | ||
| Rewarming | 10.5 (8.9–12) | 10 (8.6–13.5) | 9.8 (5.7–11.7) | 10.0 | 9.7 (8.1–12.2) | ||
| After bypass | 11.7 (10–12.7) | 11.8 (10.5–15.9) | 10 (5.9–11.4) | 12.0 | 10.9 (8.7–12.2) | ||
| Nasal temperature (°C) | |||||||
| Before bypass | 36.6 (35.3–37.0) | 36.2 (35.3–36.6) | 36.3 (35.9–37.0) | 36.1 | 36.4 (35.4–36.7) | ||
| Cooling | 27.0 (25.0–31.4) | 24.2 (21.8–28.0) | 30.2 (27.0–33.2) | 29.3 | 32.1 (30.1–33.8) | ||
| Cold bypass | 21.6 (20.4–22.5) | 17.6 (16.3–23.8) | 25.9 (22.7–26.9) | 25.4 | 30.7 (30.2–31.7) | ||
| Rewarming | 31.4 (28.5–32.4) | 29.3 (27.4–36.1) | 33.1 (30.6–35.2) | 32.3 | 35.2 (33.4–37.9) | ||
| After bypass | 35.5 (35.1–37.0) | 36.0 (35.5–37.4) | 36.2 (35.0–37.2) | 35.6 | 36.4 (35.7–37.4) | ||
| Change in oxidised cytochrome oxidase (μmol/l) | |||||||
| Before bypass | 0 | 0 | 0 | 0 | 0 | ||
| Cooling | −0.3 (−2.1 to 4.0) | −1.0 (−2.5 to 1.5) | −0.3 (−0.8 to 0.2) | −1.1 | −0.97 (−3.1 to −0.1) | ||
| Cold bypass | −0.3 (−2.1 to 5.1) | −0.8 (−2.9 to 1.9) | −0.5 (−0.8 to 1.3) | −1.57 | −2.4 (−2.9 to −0.9) | ||
| Rewarming | 0.0 (−2.5 to 5.7) | −1.1 (−3.6 to 2.3) | −0.1 (−0.8 to 1.1) | −1.96 | −1.8 (−2.9 to −0.2) | ||
| After bypass | 0.7 (−2.4 to 1.7) | 0.4 (−4.3 to 3.3) | −0.2 (−0.6 to 1.5) | −1.44 | −1.2 (−2.7 to 0.7) | ||