Comparing the effect of hydroxyethyl starch 130/0.4 with balanced crystalloid solution on mortality and kidney failure in patients with severe sepsis (6S--Scandinavian Starch for Severe Sepsis/Septic Shock trial): study protocol, design and rationale for a double-blinded, randomised clinical trial

Background

By tradition colloid solutions have been used to obtain fast circulatory stabilisation in shock, but high molecular weight hydroxyethyl starch (HES) may cause acute kidney failure in patients with severe sepsis. Now lower molecular weight HES 130/0.4 is the preferred colloid in Scandinavian intensive care units (ICUs) and 1^st choice fluid for patients with severe sepsis. However, HES 130/0.4 is largely unstudied in patients with severe sepsis.

Methods/Design

The 6S trial will randomise 800 patients with severe sepsis in 30 Scandinavian ICUs to masked fluid resuscitation using either 6% HES 130/0.4 in Ringer's acetate or Ringer's acetate alone. The composite endpoint of 90-day mortality or end-stage kidney failure is the primary outcome measure. The secondary outcome measures are severe bleeding or allergic reactions, organ failure, acute kidney failure, days alive without renal replacement therapy or ventilator support and 28-day and 1/2- and one-year mortality. The sample size will allow the detection of a 10% absolute difference between the two groups in the composite endpoint with a power of 80%.

Discussion

The 6S trial will provide important safety and efficacy data on the use of HES 130/0.4 in patients with severe sepsis. The effects on mortality, dialysis-dependency, time on ventilator, bleeding and markers of resuscitation, metabolism, kidney failure, and coagulation will be assessed.

Trial Registration

ClinicalTrials.gov: NCT00962156

Ionized calcium and acid-base status in arterial and venous whole blood during general anaesthesia

Ionized calcium, pH, pCO2 and base excess (BE) have been measured in paired samples of anaerobically collected arterial (aB) and venous whole blood (vB) from patients under general anaesthesia and during recovery. A statistically significant decrease was found in the concentration of ionized calcium in anaerobic arterial and venous blood during induction of anaesthesia and during surgery partly due to variations in pH. Statistically significant correlations were found between logcCa2+ and pH (r = -0.67, p less than 0.001), and between cCa2+ and pCO2 (r = 0.66, p less than 0.001) in anaerobic arterial blood. The in vivo slope (dlogcCa2+/dpH) was found to be -0.15 +/- 0.08 and -0.14 +/- 0.06 for arterial and venous blood, respectively (mean +/- SE). The in vitro slope estimated by equilibrating arterial and venous serum at two pCO2 values was -0.22 +/- 0.03, and -0.21 +/- 0.03, respectively (mean +/- SE). Because of a considerable variability in slope we believe that the best clinical evaluation of ionized calcium is achieved by taking measurements from anaerobically collected whole blood. Interpolating or extrapolating ionized calcium to a standard pH of 7.40 on the basis of a standard slope may introduce unnecessary errors.

Complex biochemical syndrome of hypocalcemia and hypoparathyroidism during cytotoxic treatment of an infant with leukemia

Patients with cancer are especially vulnerable to the development of hyper- and hypocalcemia. These disorders may be the basic clinical manifestation of cancer or may result from vigorous cancer treatment. During cytotoxic treatment of a child with leukemia we describe the longitudinal course of ionized calcium in a complex syndrome of hypocalcemia and hypoparathyroidism. The results suggest that the development of severe hypocalcemia can be explained on the basis of hypoparathyroidism in relation to hyperphosphatemia, hypomagnesemia, and acute renal failure. The low ionized calcium was unsuccessfully treated with several doses of calcium levulinate but successfully treated with 1 alpha-hydroxycholecalciferol.

The concentration of free calcium ions in capillary blood from neonates on a routine basis using the ICA 1

The concentration of free calcium ions (cCa2+), and pH was measured in 200 full-term infants aged 5-130 h and in 50 healthy adults aged 18-60 years with a new semi-automatic electrode system (ICA 1 Radiometer, Copenhagen) in 110 microliter capillary whole blood. The blood was obtained anaerobically by heel puncture of the infants and from the earlobe of the adults. No bias was found for the erythrocyte effect on the liquid junction potential with a haematocrit below 0.60 but for a haematocrit between 0.60 and 0.80 there was an increasing negative bias of 1-5% for this instrument. The special heparinized glass capillaries (Radiometer, Copenhagen) used for blood sampling were studied in serum pools at different levels of cCa2+ and the anticoagulant used was shown to give a bias of less than +/- 1% on the measurement of cCa2+ in the range 0.86-2.02 mmol/l. In full-term infants aged 5-48 h cCa2+ was 1.27 +/- 0.098 mmol/l (+/- 2 SD) and pH 7.42 +/- 0.07 (+/- 2 SD). In infants aged 49-96 h, cCa2+ was 1.334 +/- 0.136 mmol/l (+/- 2 SD) and pH 7.42 +/- 0.07 (+/- 2 SD). In infants, aged 97-130 h cCa2+ was 1.383 +/- 0.140 mmol/l (+/- 2 SD) and pH 7.40 +/- 0.076 (+/- 2 SD). In capillary blood from healthy adults, aged 18-60 years cCa2+ was 1.28 +/- 0.07 mmol/l (+/- 2 SD) and pH 7.42 +/- 0.03 (+/- 2 SD).(ABSTRACT TRUNCATED AT 250 WORDS)