[Adequate fluid resuscitation in septic shock with high catecholamine doses].

BACKGROUND: Appropriate fluid resuscitation is a fundamental aspect for the hemodynamic management of septic shock patients and should ideally be achieved before vasopressors and positive inotropic substances are administered. The development of hemodynamic monitoring has revealed that in some cases patients had been improperly treated with high-dose catecholamines for initially insufficient fluid resuscitation. The aim of this study was to show that in some cases it is possible to actively reduce catecholamines by a volume challenge adapted according to the individual patient needs.
MATERIAL AND METHODS: In this retrospective observational study 29 patients with septic shock in a surgical intensive care unit (ICU) at a university hospital (17 male, 12 female, mean age 71 ± 10 years) on high-dose catecholamines (median values norepinephrine 0.204 µg/kg body weight/min, dobutamine 3.876 µg/kg/min and epinephrine 0.025 µg/kg/min, ranging up to 0.810 µg/kg/min, 22.222 µg/kg/min and 0.407 µg/kg/min in 28, 20 and 17 patients, respectively) were analyzed. The extremities of the patients were initially cold with a mottled marbled appearance whereas the mean arterial pressure (MAP) was ≥ 65 mmHg. The median central venous pressure (CVP) was 17 mmHg (range 55-34 mmHg) and the mean lactate concentration was 2.78 mmol/l (range 0.93-10.67 mmol/l). The standard therapy concept consisted of a forced volume challenge combined with active reduction of catecholamines to achieve an adequate fluid loading status, guided by the passive leg raising test (PLR), clinical signs and in 19 cases by hemodynamic monitoring (pulmonary artery catheter Vigilance II(™) n = 10, FloTrac(™), Vigileo(™) n = 9 and PreSep(™) n = 5; Edwards Life Sciences). The forced volume challenge was stopped after clinical improvement with rewarmed extremities, increasing diuresis volumes and lack of improvement by PLR.
RESULTS: Catecholamine doses could be significantly reduced in all patients: norepinephrine to 0 µg/kg/min, dobutamine to 1.852 µg/kg/min and epinephrine to 0 µg/kg/min (up to 0.133 µg/kg/min, 6.289 µg/kg/min and 0.091 µg/kg/min, respectively, p < 0.05 Wilcoxon signed rank test). Volume challenge test: + 4,500 ml Ringer solution (range 0-24,000 ml) and 1,000 ml hydroxyethyl starch (range 0-2,500 ml) and mean fluid balance + 6,465 ml (range + 2,040 ml to + 27,255 ml). The median weaning time from catecholamines was 12 h (range 4-43 h). After treatment all patients showed rewarmed extremities and a decrease in mean lactate levels from 2.78 mmol/l (range 0.93-10.67 mmol/l) to 2.05 mmol/l (range 0.7-5.4 mmol/l). The measured hemodynamic constellations showed clear interindividual differences but no cardiac deterioration occurred. The median oxygenation index (paO2/FiO2) showed a statistically insignificant change from 264 mmHg (range 75-418 mmHg) to 250 mmHg (range 120-467 mmHg). Of the patients 20 survived and 9 died.
CONCLUSION: It is possible to wean a substantial proportion of septic shock patients from high-dose catecholamines in combination with a needs-adapted forced volume challenge test. The importance of appropriate fluid loading prior to the use of high catecholamine doses should be a main subject of discussion in patients with severe septic shock and was confirmed in this study. This should be oriented to clinical and if possible, hemodynamic parameters and should not be underestimated.