Introduction
Materials and methods
CRRT circuit
Patient inclusion
Statistics
Results
Patient characteristics
Number | Age | Gender | Height (cm) | Weight (kg) | BMI | pO2/FiO2 | Apache II | Days on ventilation before LARRS | Diagnosis | Outcome | Comment |
---|---|---|---|---|---|---|---|---|---|---|---|
1 | 51 | M | 180 | 90 | 35 | 95 | 31 | 11 | H1N1- pneumonia | Died on ICU day 3 | ECMO contraindication |
2 | 47 | M | 178 | 75 | 23 | 91 | 34 | 1 | H1N1- pneumonia | Died on ICU day 4 | ECMO contraindication |
3 | 57 | F | 160 | 55 | 17 | 141 | 28 | 13 | Pneumonia | Weaning and recovery | |
4 | 67 | M | 175 | 80 | 25 | 265 | 32 | 3 | COPD | Weaning and recovery | |
5 | 47 | M | 180 | 80 | 25 | 58 | 22 | 4 | Pneumonia, COPD | Bridging to ECMO | Died on multiple organ failure 12 days later |
6 | 74 | M | 170 | 90 | 31 | 93 | 35 | 1 | Pneumonia | Weaning and recovery | |
7 | 73 | F | 155 | 88 | 37 | 267 | 32 | 3 | COPD | Weaning and recovery | |
8 | 73 | F | 148 | 115 | 53 | 130 | 33 | 6 | Pneumonia | Weaning | Died 25 days later – mesenteric ischemia |
9 | 55 | M | 172 | 86 | 29 | 100 | 25 | 18 | H1N1 – pneumonia | Weaning and recovery | |
10 | 54 | M | 180 | 98 | 30 | 200 | 24 | 1 | Pneumonia | Weaning and recovery |
CO2elimination in the CRRT circuit
No. | Double-lumen catheter | Blood flow (ml/min) | Dialysate flow (L/h) | Ultrafiltration (ml/h) | Volume (ml) | Gas flow (L/min) | Oxy FiO2(vol. %) | Treatment time (hours) | |||
---|---|---|---|---|---|---|---|---|---|---|---|
t = 4 h | t = 24 h | t = 4 h | t = 24 h | t = 4 h | t = 24 h | t = 24 h | |||||
1 | 1 | 250 | 300 | 4.0 | 4.0 | 100 | 200 | −645 | 6 | 1.00 | 30 |
2 | 1 | 330 | 400 | 2.0 | 2.0 | 200 | 0 | −705 | 4 | 1.00 | 84 |
3 | 1 | 400 | 400 | 2.0 | 2.0 | 0 | 150 | 605 | 4 | 0.50 | 45 |
4 | 1 | 400 | 400 | 2.0 | 2.0 | 0 | 100 | 1,715 | 6 | 0.40 | 215 |
5 | 2 | 300a | n.a. | 2.0 a | n.a. | 100 a | n.a. | n.a. | 6 | 0.21 | 2.5 |
6 | 1 | 500 | 450 | 3.0 | 3.0 | 0 | 100 | 1,340 | 6 | 0.21 | 191 |
7 | 1 | 320 | 250 | 2.0 | 2.0 | 100 | 150 | −3,345 | 4 | 0.21 | 83 |
8 | 2 | 400 | 450 | 2.0 | 1.5 | 40 | 100 | −2,055 | 6 | 0.21 | 71 |
9 | 1 | 400 | 500 | 2.0 | 2.0 | 0 | 0 | 180 | 6 | 0.21 | 92 |
10 | 1 | 250 | 250 | 2.0 | 2.0 | 50 | 0 | 2,945 | 4 | 0.21 | 134 |
Blood-gas changes during the course of therapy
No. | Art. pH | Art. pCO2 | Art. HCO3 | ||||||
---|---|---|---|---|---|---|---|---|---|
t = 0 | t = 4 hours | ΔpH | t = 0 | t = 4 hours | ΔpCO2 | t = 0 | t = 4 hours | ΔHCO3 | |
1 | 7.17 | 7.25 | 0.08 | 58 | 47 | −11 | 20 | 20 | 0 |
2 | 7.24 | 7.28 | 0.04 | 56 | 51 | −5 | 22 | 24 | 2 |
3 | 7.10 | 7.29 | 0.19 | 77 | 49 | −28 | 23 | 23 | 0 |
4 | 7.18 | 7.34 | 0.16 | 69 | 52 | −17 | 25 | 27 | 2 |
5 | 7.24 | 7.21a | −0.03 | 88 | 90a | 2 | 37 | 34a | −3 |
6 | 7.07 | 7.18 | 0.11 | 77 | 57 | −20 | 20 | 19 | −1 |
7 | 7.37 | 7.44 | 0.07 | 55 | 44 | −11 | 31 | 30 | −1 |
8 | 7.16 | 7.24 | 0.09 | 66 | 55 | −11 | 23 | 23 | 0 |
9 | 7.18 | 7.31 | 0.13 | 79 | 55 | −24 | 29 | 27 | −2 |
10 | 7.18 | 7.37 | 0.19 | 65 | 36 | −29 | 23 | 21 | −2 |
Mean
|
7.18
|
7.30
|
0.12
|
69.00
|
49.56
|
−17.3
|
25.3
|
23.78
|
−0.22
|
Number | FiO2(%) | PEEP (mm Hg) | Tidal volume (ml/pbw) | Pmean(mm Hg) | Pmax(mm Hg) | Breathing rate | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
t = 0 h | t = 4 h | t = 24 h | t = 0 h | t = 4 h | t = 24 h | t = 0 h | t = 4 h | t = 24 h | t = 0 h | t = 4 h | t = 24 h | t = 0 h | t = 4 h | t = 24 h | t = 0 h | t = 4 h | t = 24 h | |
1 | 0.85 | 0.95 | 1.00 | 14 | 14 | 14 | 8.6 | 8.0 | 8.6 | 22 | 22 | 23 | 32 | 32 | 32 | 25 | 23 | 20 |
2 | 1.00 | 0.95 | 1.00 | 14 | 16 | 20 | 7.5 | 5.8 | 5.1 | 22 | 22 | 23 | 32 | 32 | 30 | 22 | 22 | 30 |
3 | 0.55 | 0.55 | 0.50 | 10 | 10 | 10 | 8.3 | 8.2 | 7.6 | 19 | 18 | 19 | 35 | 32 | 34 | 30 | 28 | 28 |
4 | 0.40 | 0.40 | 0.35 | 8 | 8 | 8 | 8.2 | 8.2 | 7.2 | 17 | 17 | 15 | 32 | 31 | 27 | 20 | 20 | 20 |
5 | 1.00 | 1.00a | n.a. | 13 | 13 a | n.a. | 8.6 | 6.5 a | n.a. | 23 | 23 a | n.a. | 40 | 40 a | n.a. | 20 | 24 a | n.a. |
6 | 1.00 | 0.95 | 0.60 | 12 | 12 | 12 | 9.0 | 8.8 | 8.0 | 20 | 19 | 19 | 34 | 33 | 31 | 20 | 20 | 20 |
7 | 0.37 | 0.37 | 0.37 | 12 | 12 | 10 | 9.6 | 9.5 | 8.1 | 16 | 14 | 13 | 27 | 23 | 21 | 12 | 12 | 14 |
8 | 0.50 | 0.50 | 0.50 | 15 | 15 | 15 | 9.8 | 8.4 | 6.7 | 21 | 21 | 21 | 33 | 33 | 30 | 20 | 20 | 26 |
9 | 0.80 | 0.70 | 0.60 | 12 | 12 | 14 | 7.9 | 9.6 | 7.7 | 19 | 19 | 18 | 28 | 28 | 25 | 28 | 28 | 24 |
10 | 0.40 | 0.40 | 0.50 | 12 | 12 | 12 | 6.6 | 8.6 | 7.1 | 19 | 19 | 18 | 32 | 32 | 28 | 26 | 26 | 26 |
Mean
|
0.69
|
0.64
|
0.60
|
12.20
|
12.33
|
12.78
|
8.41
|
8.34
|
7.34
|
19.80
|
19.00
|
18.78
|
32.50
|
30.67
|
28.67
|
22.30
|
22.11
|
23.11
|
Hemodynamic stability
Number | MAP (mm Hg) | Heart rate | Norepinephrine (mg/h) | Norepinephrine (μg/kg/min) | Lactate (mg/dl) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
t = 0 h | t = 4 h | t = 24 h | t = 0 h | t = 4 h | t = 24 h | t = 0 h | t = 4 h | t = 24 h | t = 0 h | t = 4 h | t = 24 h | t = 0 h | t = 4 h | t = 24 h | |
1 | 83 | 73 | 66 | 120 | 110 | 100 | 2.6 | 3.2 | 5.2 | 0.48 | 0.59 | 0.96 | 49 | 59 | 124 |
2 | 57 | 73 | 80 | 120 | 110 | 125 | 0.2 | 0.2 | 0.4 | 0.04 | 0.04 | 0.08 | 12 | 12 | 4.2 |
3 | 80 | 87 | 73 | 80 | 85 | 90 | 0.2 | 0.0 | 0.0 | 0.06 | 0.00 | 0.00 | 7 | 9 | 6 |
4 | 80 | 80 | 87 | 110 | 105 | 100 | 0.6 | 0.5 | 0.3 | 0.13 | 0.10 | 0.06 | 14 | 16 | 18 |
5 | 73 | 76a | n.a. | 110 | 100 a | n.a. | 0.2 | 0.3 a | n.a. | 0.04 | 0.06 a | n.a. | 11 | 9 a | n.a. |
6 | 70 | 77 | 93 | 110 | 90 | 90 | 5.0 | 2.0 | 1.0 | 0.93 | 0.37 | 0.18 | 43 | 47 | 12 |
7 | 70 | 73 | 90 | 70 | 65 | 95 | 0.1 | 0.0 | 0.0 | 0.02 | 0.00 | 0.00 | 6 | 7 | 9 |
8 | 66 | 63 | 73 | 110 | 90 | 90 | 1.2 | 1.2 | 0.9 | 0.17 | 0.17 | 0.13 | 12 | 13 | 14 |
9 | 80 | 82 | 73 | 105 | 110 | 110 | 0.0 | 0.0 | 0.0 | 0.00 | 0.00 | 0.00 | 7 | 7 | 8 |
10 | 73 | 87 | 93 | 100 | 85 | 80 | 1.9 | 0.9 | 0.0 | 0.32 | 0.15 | 0.00 | 10 | 12 | 9 |
Mean
|
73.20
|
77.22
|
80.89
|
103.50
|
94.44
|
97.78
|
n.a.
|
n.a.
|
n.a.
|
0.22
|
0.16
|
0.16
|
17.10
|
20.22
|
22.69
|
Patients’ outcome
Discussion
Conclusions
Key messages
-
Implementation of a hollow-fiber gas exchanger in a low-flow CRRT circuit was feasible and safe
-
Low-flow CO2 removal in a CRRT circuit significantly removed CO2 and allowed rapid correction of arterial pH in critically ill patients with acute renal and respiratory failure
-
Correction of arterial pH contributed to hemodynamic stabilization of the patient
-
Low-flow CO2 did not significantly contribute to systemic oxygenation
-
Low-flow CO2 removal complements but did not substitute ECMO or PECLA therapy, when ECMO/PECLA was indicated