Isotonic maintenance solutions cause an importantly more positive cumulative fluid balance and substantial hyperchloremia revealing them as an independent cause of potentially detrimental fluid sodium and chloride overload, problems which have mainly been accredited to resuscitation fluids to date. In adult patients undergoing major surgery, hyponatremia is encountered more frequently under maintenance therapy containing 54 mmol per liter of sodium but it is mostly mild and asymptomatic. |
Introduction
Materials and methods
Trial design and patients
Randomization and masking
Procedures
Outcomes
Sample size and statistical analysis
Results
Na54 (n = 34) | Na154 (n = 35) | p value | |
---|---|---|---|
Patient characteristics | |||
Age (years) | 62.7 (9.0) | 62.2 (7.2) | 0.80 |
Sex (% female) | 12 (35.3) | 7 (20.0) | 0.16 |
Body weight (kg) | 75.6 (13.1) | 77.7 (14.9) | 0.53 |
Body mass index (kg/m2) | 25.7 (4.7) | 25.8 (4.3) | 0.95 |
Baseline creatinine (mg/dL) | 0.76 (0.16) | 0.78 (0.14) | 0.62 |
Estimated glomerular filtration rate (eGFR) (mL/min/1.73 m2) | 104 (20.9) | 107 (26.3) | 0.60 |
Characteristics of surgeries | |||
Type of surgery | |||
(Bi)lobectomy | 24 (70.6) | 26 (74.3) | 0.75 |
Wedge resection/segmentectomy | 9 (26.5) | 7 (20.0) | 0.75 |
Other | 1 (2.9) | 2 (5.7) | 0.75 |
Surgical approach | |||
Thoracotomy | 19 (55.9) | 21 (60.0) | 0.93 |
Robot-assisted thoracic surgery (RATS) | 10 (29.4) | 9 (25.7) | 0.93 |
Video-assisted thoracic surgery (VATS) | 5 (14.7) | 5 (14.3) | 0.93 |
Lung cancer as the reason for surgery | 33 (97)a | 34 (97)b | 1.00 |
Use of patient-controlled epidural analgesia (PCEA) | 33 (97.1) | 29 (82.9) | 0.11 |
Duration of surgery (hours) | 3.1 (2.4–3.6) | 3.8 (2.7–4.3) | 0.04 |
Duration of mechanical ventilation (hours)c | 4.1 (3.6–4.8) | 4.8 (4.0–5.4) | 0.07 |
Volume of intraoperative resuscitation fluids (mL) | 1500 (1000–2000) | 1500 (1000–2250) | 0.74 |
Dose of intraoperative noradrenaline (mcg) | 491 (162–906) | 778 (184–1949) | 0.09 |
Study period characteristics | |||
Mean duration of study treatment (hours) | 39.3 (15.5) | 38.5 (16.7) | 0.44 |
Median duration of study treatment (hours) | 29.5 (26.7–50.3) | 29.3 (25.3–48.1) | 0.44 |
Cumulative volume of blood loss and drain outputs (mL) | 795 (450–1060) | 890 (450–1940) | 0.24 |
Cumulative urine output (mL) | 2178 (1460–3100) | 1945 (1290–3890) | 0.33 |
Cumulative volume of administered study fluid (mL) | 2772 (2159–4252) | 2619 (2048–4286) | 0.76 |
Cumulative volume of postoperative resuscitation fluids (mL) | 0 (0–1000) | 0 (0–500) | 0.49 |
Cumulative volume of oral fluid intake (mL) | 400 (5–925) | 600 (200–1325) | 0.11 |
Cumulative off-study fluid balance (mL) | 1508 (890–2175) | 1425 (1020–2200) | 0.93 |
Primary outcome
Secondary outcomes (electrolyte disturbances) and effect on electrolyte levels over time
Na54 (n = 34) | Na154 (n = 35) | p value | |
---|---|---|---|
Secondary outcomes: electrolyte disturbances | |||
Sodium | |||
Hyponatremia (< 135 mmol/L) | 4 (11.8) | 0 (0) | 0.04 |
Hyponatremia (< 130 mmol/L) | 1 (2.94) | 0 (0) | 0.31 |
Hypernatremia (> 145 mmol/L) | 0 (0) | 3 (8.6) | 0.08 |
Hypernatremia (> 150 mmol/L) | 0 (0) | 0 (0) | |
Chloride | |||
Hypochloremia (< 101 mmol/L) | 6 (17.6) | 0 (0) | 0.01 |
Hyperchloremia (> 109 mmol/L) | 4 (11.8) | 24 (68.6) | < 0.001 |
Safety outcomes | |||
Clinical outcomes | |||
Acute kidney injury (AKIN stage 1 or higher) | 1 (2.9) | 1 (2.9) | 0.98 |
Need for renal replacement therapy | 0 (0) | 0 (0) | |
Lowest paO2/FiO2 ratio after ICU admission | 356 (269–390) | 334 (255–383) | 0.55 |
New-onset atrial fibrillation | 1 (2.9) | 4 (11.4) | 0.17 |
Predefined (serious) adverse events leading to the termination of study period by the treating clinicians | |||
Clinical or radiographic fluid overload | 1 (2.9) | 6 (17.1) | 0.05 |
Evolving or symptomatic hyponatremia | 0 (0) | 0 (0) | |
Hyperkalemia | 0 (0) | 1 (2.9) | 0.32 |
Other (serious) adverse events | 1 (2.9)a | 0 (0) | 0.31 |
Hospital mortality | 1 (2.9) | 0 (0) | 0.31 |