Background
Methods
Participants
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Patient ≥ 18 year old who gave his (her) informed consent (or his (her) relative) or delayed
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Patient with septic shock according to the Surviving Sepsis Campaign criteria [15]
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Patient on mechanical ventilation without spontaneous breathing
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Patients in whom a fluid challenge was required for the following reasons, according to physician decision:
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Persistent hypotension despite fluid resuscitation of 20 to 40 mL/kg and requiring vasopressors as indicated in 2012 Surviving Sepsis Campaign criteria [15]
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ScVO2 < 70% or SvO2 < 65%.
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Urine output < 0.5 mL h−1 during two consecutive hours
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Skin mottles
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Arterial lactate concentration > 2 mMol L−1
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Informed consent not obtained
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Prisoner
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Patient under legal guardianship
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Parturient
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Severe mitral or aortic regurgitation
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Patients with cardiac arrhythmia
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Poor echogenicity
Study protocol
Intervention, fluid responsiveness definition (Fig. 1)
Measured parameters and time of measurement
Statistical analysis
Results
Patient characteristics and flow chart
Variables | |
---|---|
Female | 50 (35%) |
Age (years) | 64 ± 14 |
Weight (kg) | 75 ± 20 |
Height (cm) | 168 ± 9 |
BMI (kg m−2) | 26.8 ± 7.1 |
SAPS II score at admission | 53 [43–63] |
SOFA score at inclusion | 10 [8–12] |
Comorbidities (n, %)
| |
Hypertension | 53 (37%) |
Coronary artery disease | 24 (17%) |
Cardiac heart failure | 5 (4%) |
Diabetes mellitus | 17 (12%) |
COPD | 17 (12%) |
Creatinine clearance < 30 ml min−1 | 8 (6%) |
Origin of sepsis (n, %) | |
Pulmonary | 62 (43%) |
Intra-abdominal | 58 (41%) |
Urinary tract | 12 (8%) |
Bacteremia | 7 (5%) |
Miscellaneous | 15 (11%) |
Variables | |
---|---|
Heart rate (bpm) (MD = 0) | 94 ± 24 |
Mean arterial pressure (mmHg) (MD = 0) | 74 ± 12 |
Tidal volume (mL/Kg) (MD = 0) | 6.0 ± 1.0 |
Respiratory rate (cycle min−1) (MD = 0) | 22 [18–25] |
PEEP (cm H2O) (MD = 0) | 6 [5–8] |
Pplateau (cm H2O) (MD = 9) | 19 [17–23] |
Norepinephrine infusion rate (μg kg min−1) | 0.41 [0.22–0.95] |
Arterial blood lactate (mMol L−1) (MD = 5) | 1.95 [1.3–3.55] |
ScvO2 (MD = 58) | 77 [68–83] |
pH (MD = 2) | 7.34 [7.25–7.40] |
PaO2 (mmHg) (MD = 2) | 99 [79–128] |
PaCO2 (mmHg) (MD = 3) | 40 [35–46] |
Hemoglobin (g dL−1) (MD = 2) | 10.7 [9.4–12.1] |
Estimated ejection fraction (MD = 7) | |
< 40% | 16 (11%) |
≥ 40% | 120 (84%) |
VTI (cm) (MD = 0) | 16.6 ± 5 |
E wave (m s−1) (MD = 1) | 0.69 ± 0.20 |
A wave (m s−1) (MD = 3) | 0.74 ± 0.23 |
E′ wave (m s−1) (MD = 2) | 0.1 [0.07–0.13] |
S wave (cm s−1) (MD = 13) | 11.7 ± 5.1 |
E/A ratio (MD = 3) | 1.03 ± 0.55 |
E/E′ ratio (MD = 3) | 7.0 ± 3.7 |
Fluid challenge assessment
Variables | NR (n = 67) | PR (n = 39) | TR (n = 37) | p value for all groups | p value NR vs. PR | p value NR vs. TR | p value PR vs. TR |
---|---|---|---|---|---|---|---|
Age (years) | 62.6 ± 13.7 | 67.7 ± 14.1 | 64.5 ± 14.1 | 0.19 | 0.07 | 0.50 | 0.33 |
SAPS II at admission | 48.5 [42.3–57.8] | 58 [48–73.5] | 55 [45–62] | 0.053 | 0.017 | 0.23 | 0.29 |
SOFA at inclusion | 9 [8–11.8] | 10 [9–13] | 10 [7–11] | 0.34 | 0.14 | 0.86 | 0.33 |
Arterial lactate at baseline (mMol/l) | 1.8 [1.3–3.1] | 2.55 [1.33–5.43] | 1.9 [1.1–3.45] | 0.16 | 0.10 | 0.78 | 0.08 |
ICU mortality rate | 25.4% | 46.2% | 37.8% | 0.08 | 0.048 | 0.27 | 0.62 |
Norepinephrine ≥ 0.5 μg kg−1 min−1 | 0.34 [0.22–0.67] | 0.64 [0.32–1.29] | 0.39 [0.20–0.95] | 0.07 | 0.02 | 0.84 | 0.13 |
LVEF | 0.88 | 1.00 | 0.76 | 0.73 | |||
< 40% | 7 (11.1%) | 4 (10.5%) | 5 (14.3%) | ||||
≥ 40% | 56 (88.9%) | 34 (89.5%) | 30 (85.7%) |
Variables | T0 (baseline) | T10 | T20 | T30 | |
---|---|---|---|---|---|
MAP (mmHg) | NR | 73 ± 9.9 | 77.7 ± 11.3 | 76.5 ± 11.1 | 76 ± 11.7 |
PR | 75 ± 15.2 | 81.7 ± 15.6 | 82.6 ± 14.8 | 80.8 ± 14.6 | |
TR | 73.1 ± 10.7 | 81.4 ± 13.2 | 76.7 ± 14.4 | 75.9 ± 12.6 | |
SAP (mmHg) | NR | 114.7 ± 19.5 | 123.8 ± 22.2 | 122.4 ± 21.5 | 120.3 ± 21.7 |
PR | 112.2 ± 22.8 | 126.2 ± 22.4 | 125 ± 21.4 | 121.3 ± 22 | |
TR | 111.9 ± 18.5 | 127.3 ± 21.6 | 120.4 ± 21.3 | 118.9 ± 20.8 | |
DAP (mmHg) | NR | 54.6 ± 8.9 | 57.3 ± 9.8 | 56.4 ± 9.8 | 56.1 ± 9.8 |
PR | 59.4 ± 13 | 62.1 ± 12.2 | 61.6 ± 13.1 | 60.7 ± 12.2 | |
TR | 55.2 ± 8.8 | 59 ± 10.7 | 56.6 ± 11.5 | 56.5 ± 10.7 | |
HR (bpm) | NR | 93.5 ± 22.1 | 91.3 ± 21.4 | 90.3 ± 22.8 | 91.7 ± 21.9 |
PR | 92 ± 25.9 | 90.8 ± 23.5 | 91.7 ± 24.6 | 91.8 ± 24.6 | |
TR | 96.4 ± 24.3 | 93.3 ± 22.3 | 93.6 ± 23.1 | 94.5 ± 23.6 | |
EtCO2 (mmHg) | NR | 32.2 ± 6.2 | 31.7 ± 5.6 | 31.6 ± 5.7 | 31.7 ± 5.8 |
PR | 29.9 ± 5.6 | 29.8 ± 5.4 | 30.3 ± 5.6 | 29.9 ± 5.4 | |
TR | 31 ± 6.6 | 31.9 ± 6.6 | 32.1 ± 7 | 32 ± 7.4 | |
VTI (cm) | NR | 18.2 ± 5.3 | 19 ± 5.8 | 18.8 ± 5.9 | 18.6 ± 5.9 |
PR | 14.3 ± 3.6 | 19.5 ± 4.9 | 18.6 ± 5.2 | 18.9 ± 5.3 | |
TR | 16.2 ± 4.9 | 20.4 ± 5.5 | 18.1 ± 5.4 | 17.3 ± 5.4 | |
E wave (m s−1) | NR | 0.7 ± 0.2 | 0.9 ± 0.2 | 0.8 ± 0.2 | 0.8 ± 0.2 |
PR | 0.6 ± 0.2 | 0.8 ± 0.2 | 0.7 ± 0.2 | 0.7 ± 0.2 | |
TR | 0.7 ± 0.2 | 0.8 ± 0.2 | 0.7 ± 0.2 | 0.7 ± 0.2 | |
A wave (m s−1) | NR | 0.7 ± 0.2 | 0.8 ± 0.2 | 0.8 ± 0.2 | 0.8 ± 0.2 |
PR | 0.8 ± 0.2 | 0.8 ± 0.2 | 0.8 ± 0.2 | 0.8 ± 0.2 | |
TR | 0.7 ± 0.3 | 0.8 ± 0.3 | 0.8 ± 0.2 | 0.8 ± 0.3 | |
E/A ratio | NR | 1.1 ± 0.4 | 1.2 ± 0.4 | 1.1 ± 0.4 | 1.1 ± 0.4 |
PR | 0.9 ± 0.4 | 1 ± 0.4 | 1 ± 0.5 | 1 ± 0.5 | |
TR | 1.1 ± 0.8 | 1.2 ± 1.2 | 1 ± 0.3 | 0.9 ± 0.3 | |
E′ wave (m s−1) | NR | 0.1 ± 0.1 | 0.2 ± 0.2 | 0.2 ± 0.3 | 0.1 ± 0.2 |
PR | 0.2 ± 0.3 | 0.3 ± 0.4 | 0.3 ± 0.4 | 0.2 ± 0.4 | |
TR | 0.2 ± 0.2 | 0.1 ± 0.1 | 0.1 ± 0.2 | 0.1 ± 0.2 | |
E/E′ ratio | NR | 7.9 ± 4 | 8 ± 4.2 | 7.8 ± 3.7 | 8.3 ± 3.9 |
PR | 5.7 ± 3.4 | 6.5 ± 3.6 | 6 ± 3.6 | 6.4 ± 3.4 | |
TR | 6.6 ± 3.2 | 8 ± 3 | 7.7 ± 3.3 | 7.4 ± 3.5 | |
ScVO2 (%) | NR | 74 ± 12.1 | 74.4 ± 11.7 | NA | 74 ± 12.1 |
PR | 76.1 ± 11.3 | 76.4 ± 8.2 | NA | 76.1 ± 11.3 | |
TR | 78.5 ± 8.5 | 79.1 ± 9.2 | NA | 78.5 ± 8.5 | |
Arterial lactate (mmol L−1) | NR | 2.7 ± 2.4 | 2.7 ± 2.8 | NA | 2.6 ± 2.8 |
PR | 3.4 ± 2.6 | 3.0 ± 2.0 | NA | 3.2 ± 2.1 | |
TR | 2.6 ± 2.1 | 2.3 ± 1.9 | NA | 2.5 ± 2.1 |
Discussion
Key findings
Relationship with previous papers
Implications of study findings
Study limitations
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First, the present study does not report any outcome endpoints.
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Second, one could argue that MAP and ScvO2 were in normal ranges at baseline, suggesting adequate blood volume and cardiac output, and ruling out indication of fluid infusion. However, during sepsis, SvO2 can be elevated due to microcirculatory alterations and may not reflect adequate tissue oxygenation explaining that fluid challenge has been performed despite normal SvO2 value in the present study. Similarly, fluid challenge has also been performed despite a mean 74 mmHg MAP value at baseline as normal MAP does not rule out potential excess of norepinephrine associated with occult hypovolemia.