Table 1.
Baseline characteristics of the study cohort
| Entire cohort (n=243) | Serial Lactate Group (SL, n=132) | No Serial Lactate Group (NL, n=111) | p | |
|---|---|---|---|---|
|
| ||||
| Baseline characteristics | ||||
|
| ||||
| Age, yr | 61.1 (16.7) | 61.6 (15.8) | 60.5 (17.8) | 0.59 |
|
| ||||
| Female, n (%) | 106 (43.6) | 58 (44) | 48 (43) | 0.91 |
|
| ||||
| Race, n (%) | 0.89 | |||
| - Caucasian | 102 (42.0) | 55 (42) | 47 (42) | |
| - Other | 141 (58.0) | 77 (58) | 64 (58) | |
|
| ||||
| Weight (kg) | 77.1 (63.5–90.7) | 77.9 (63.7–81.6) | 77.1 (63.5–95.3) | 0.44 |
|
| ||||
| Height (in) | 67.0 (63.0–70.0) | 67.0 (63.0–70.0) | 66.0 (63.0–70.0) | 0.65 |
|
| ||||
| PBW (kg) | 62.6 (54.7–73.0) | 61.6 (54.7–73.0) | 62.6 (52.4–73.0) | 0.65 |
|
| ||||
| BMI | 26.1 (21.3–31.3) | 25.7 (21.1–29.7) | 27.2 (21.9–32.9) | 0.11 |
|
| ||||
| Comorbidities, n (%) | ||||
|
| ||||
| CHF | 34 (14.0) | 15 (11) | 19 (17) | 0.20 |
|
| ||||
| Diabetes Mellitus | 79 (32.5) | 37 (28) | 42 (38) | 0.10 |
|
| ||||
| COPD | 37 (15.2) | 12 (9) | 25 (22) | <0.01 |
|
| ||||
| ESRD | 18 (7.4) | 8 (6) | 10 (9) | 0.38 |
|
| ||||
| Liver Disease | 32 (13.2) | 17 (13) | 15 (13) | 0.88 |
|
| ||||
| Malignancy | 43 (17.7) | 25 (19) | 18 (16) | 0.58 |
|
| ||||
| Immunosuppression | 24 (9.9) | 13 (9.8) | 11 (9.9) | 0.99 |
|
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| Alcohol | 21 (8.6) | 15 (11.4) | 6 (5.4) | 0.10 |
|
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| Temperature, C | 36.7 (1.6) | 36.7 (1.6) | 36.7 (1.5) | 1.0 |
|
| ||||
| SBP | 83.2 (25.2) | 81.5 (23.6) | 85.2 (27.0) | 0.26 |
|
| ||||
| HR | 123.6 (24.5) | 122.4 (24.5) | 125.1 (24.5) | 0.39 |
|
| ||||
| SpO2, (%) | 95.0 (93.0–98.0) | 95.0 (93.0–98.0) | 94.0 (93.0–98.0) | 0.39 |
|
| ||||
| WBC | 14.2 (9.9–19.6) | 14.0 (9.2–18.9) | 14.5 (10.7–20.0) | 0.24 |
|
| ||||
| Hemoglobin | 11.5 (3.0) | 11.6 (2.9) | 11.5 (3.1) | 0.92 |
|
| ||||
| Platelet | 203.0 (137.0–301.0) | 193.0 (125.0–296.0) | 213.0 (146.0–302.0) | 0.49 |
|
| ||||
| Bilirubin | 0.7 (0.4–1.6) | 0.8 (0.4–1.4) | 0.6 (0.3–1.7) | 0.85 |
|
| ||||
| Creatinine | 1.3 (0.9–2.4) | 1.4 (1.0–2.8) | 1.3 (0.9–1.7) | 0.09 |
|
| ||||
| INR | 1.4 (1.2–1.7) | 1.4 (1.2–1.7) | 1.4 (1.1–1.7) | 0.49 |
|
| ||||
| pH | 7.28 (0.14) | 7.28 (0.13) | 7.28 (0.15) | 0.73 |
|
| ||||
| Albumin | 3.1 (0.8) | 3.1 (0.8) | 3.1 (0.7) | 0.81 |
|
| ||||
| Lactate, (mmol/L) | 5.7 (4.6–8.1) | 5.8 (4.6–8.3) | 5.6 (4.7–7.0) | 0.51 |
|
| ||||
| SOFA* | 4.0 (2.0–7.0) | 4.0 (2.0–7.0) | 4.0 (2.0–8.0) | 0.79 |
|
| ||||
| Source of infection, n (%) | ||||
|
| ||||
| Pulmonary | 44 (18.1) | 18 (13.6) | 26 (23.4) | 0.05 |
|
| ||||
| Urinary | 47 (19.3) | 28 (21.2) | 19 (17.1) | 0.42 |
|
| ||||
| Intra-abdominal | 17 (7.0) | 11 (8.3) | 6 (5.4) | 0.37 |
|
| ||||
| Skin/soft tissue | 13 (5.3) | 5 (3.8) | 8 (7.2) | 0.24 |
|
| ||||
| Blood | 22 (9.0) | 13 (9.8) | 9 (8.1) | 0.64 |
|
| ||||
| ED LOS (min) | 407 (298.0–570.0) | 458 (332.0–660.5) | 359 (240.0–472.0) | <0.01 |
|
| ||||
| Process-of-care variables | ||||
|
| ||||
| Time to antibiotics, min** | 145.0 (91.0–247.0) | 135.0 (87.0–258.5) | 150.0 (100.0–243.0) | 0.44 |
|
| ||||
| Intravenous crystalloid, L | 3.1 (1.8) | 3.6 (1.7) | 2.5 (1.8) | <0.01 |
|
| ||||
| Vasopressor use, n (%) | 85 (34.5) | 44 (33) | 41 (37) | 0.77 |
|
| ||||
| pRBC transfusion, n(%) | 44(18.1) | 24 (18) | 20 (18) | 0.97 |
|
| ||||
| Corticosteroids, n (%) | 25 (10.3) | 17 (13) | 8 (7.4) | 0.15 |
|
| ||||
| Mechanical ventilation, n (%) | 97 (39.9) | 42 (31.8) | 55 (49.5) | <0.01 |
|
| ||||
| Tidal volume, mL | 500 (450–550) | 500 (450–500) | 500 (450–562.5) | 0.10 |
|
| ||||
| Tidal volume, mL/kg PBW | 7.9 (7.1–9.1) | 7.7 (7.0–8.9) | 8.4 (7.1–9.4) | 0.14 |
|
| ||||
| Peak pressure, cmH2O (n=81) | 25.0 (22.0–33.5) | 25.0 (22.0–32.5) | 26.5 (21.0–33.5) | 0.80 |
|
| ||||
| Plateau pressure, cm H20 (n=74) | 18.5 (16.0–24.0) | 17.5 (15.0–22.5) | 19.0 (16.0–24.0) | 0.22 |
Continuous variables are reported as mean (standard deviation), and median (interquartile range). PBW: predicted body weight; BMI: body mass index; CHF: congestive heart failure; COPD: chronic obstructive pulmonary disease; ESRD: end stage renal disease; SBP: systolic blood pressure; HR: heart rate; SpO2: peripheral oxygen saturation; WBC: white blood count; INR: international normalized ratio; SOFA: sequential organ failure assessment; ED: emergency department; LOS: length of stay, pRBC: packed red blood cell
*
Modified score, which excludes Glasgow Coma Score
**
All patients in the study received antimicrobial therapy.