Dopexamine Test in septic shock with hyperlactatemia.

OBJECTIVE: To evaluate the 6 hours haemodynamic effects of dopexamine (DPX) infusion in septic shock patients with persistent hyperlactatemia treated with high dose of norepinephrine (NE). STUDY DESIGN: Preliminary, prospective, uncontrolled study. PATIENTS: Twenty-one septic shock with NE>0.5 µg/kg/min, venous mixed oxygen saturation (ScvO(2)/SvO(2))>70%, cardiac index (CI)>3.5 l/min/m(2) and lactate>3 mmol/l. INTERVENTIONS: Infusion of DPX at 0.5 µg/kg/min. After 6 hours, patients were classified as DPX-responders or DPX-non-responders according to the presence or not of a decrease ≥20% in lactatemia. MEASUREMENT: DPX-responders and DPX-non-responders were compared with MAP, CI, central venous pressure (CVP), heart rate (HR) before infusion of DPX (h0), 30 minutes (h0.5) and 6 hours later (h6); and with NE infusion rate at h0 and h6. RESULTS: Eleven (52%) patients were DPX-responders and 10 (48%) DPX-non-responders. At H0.5, DPX-responders increased MAP more than DPX-non-responders (+21% versus +7%, P=0.01) with no change in CI, CVP and HR in both groups. At h0.5, an increase in MAP higher than 14%, compared to h0, could predict lactate clearance at h6 (sensitivity 91%, specificity 90%). From h0 to h6, increase in MAP (80±7 versus 70±8 mmHg, P<0.01) in DPX-responders allowed reduction in NE infusion (from 1.6±0.3 to 0.4±0.3 µg/kg/min, P<0.01); 28-day mortality was lower in DPX-responders than in DPX-non-responders (7 versus 90%, P<0.01). CONCLUSION: This study suggests that DPX did induce a decrease in lactatemia in 52% of septic shock, that could be predict by an increase in MAP (>14% within 30 minutes). Controlled studies are needed to confirm those preliminary results.

[Practical means of temperature control]. / Contrôle de la température : les moyens d'action en pratique.

Mild therapeutic hypothermia can provide neuroprotection in some clinical situations (postanoxic cardiac arrest, neonatal anoxia). Techniques to induce hypothermia are based on thermal exchanges, in particular conduction and convection. There are several external cooling techniques: application of ice packs, cold moistened towel, ice-cold devices, ventilation of cooled air, water- or air-cooled circulating mattresses or devices. These techniques are frequently used because of their reduced cost. Internal cooling techniques are more limited and more expensive: ice-cold perfusion, endovascular catheters, extracorporeal circulation, but they offer more efficiency (high speed to reach and to maintain the temperature target). Drugs can also induce hypothermia, either by decreasing body temperature, e.g. paracetamol and aspirin, or by blocking shivering, e.g. neuromuscular blocking agents, opioids and alpha2-agonist.