Large-pore hemodialysis in acute endotoxin shock.
OBJECTIVE
This study was undertaken to test the hypothesis that hemodialysis with a large-pore membrane would improve heart function during acute endotoxin shock.


METHODS
Large animal laboratory.


METHODS
Eighteen mongrel dogs were instrumented to measure left ventricular maximum end-systolic elastance (left ventricular maximum elastance at end systole), cardiac output, circumflex artery blood flow, and myocardial mechanical efficiency (CO x MAP/MVO2, where CO is cardiac output, MAP is mean arterial pressure, and MVO2 is myocardial oxygen consumption). Plasma catecholamine concentrations were determined by high-performance liquid chromatography. Endotoxin shock was induced by infusing 5.0 microg/kg/min of Escherichia col 0127:B8 endotoxin in the portal vein for 60 mins, followed by 2.0 microg/kg/min of constant infusion. Control dogs (n = 6) received 4.0 mL/kg/min of saline; hemodialysis dogs (n = 6) underwent venovenous hemodialysis in 50-min intervals using a polysulfone filter (1.2 m2; mean pore size, 0.50 nm; blood flow rate, 400 mL/min; ultrafiltrate, "zero-balanced"); shams (n = 5) were treated identically to hemodialysis dogs, except that no convective dialysis was performed. A fourth group (n = 6) was treated with dopamine (5.0-7.0 microg/kg/min, optimal dose for contractile increase based on dose-response studies).


RESULTS
After 2 hrs of treatment, left ventricular maximum elastance at end systole increased and was unchanged in controls (30 +/- 5 mm Hg/mm) and shams (24 +/- 6 mm Hg/mm) compared with basal control. Hemodialysis treatment increased contractility (53 +/- 4 mm Hg/mm), as did dopamine treatment (54 +/- 7 mm Hg/mm). Endotoxin shock reduced mechanical efficiency to 45% of basal control; with hemodialysis treatment, left ventricular efficiency returned to 64% of basal control measurement, compared with 49% with dopamine treatment. During treatment, myocardial glucose uptake was increased with hemodialysis compared with other groups. No difference was observed among groups for left ventricular end-diastolic pressures or dimensions, or catecholamine concentrations.


CONCLUSIONS
Large-pore hemodialysis increased left ventricular contractility to a similar degree as dopamine and provided a marginal improvement in myocardial glucose uptake and mechanical efficiency.
Kline
J A
JA
Department Emergency Medicine Research, Cannon Research Center, Carolinas Medical Center, Charlotte, NC 28232, USA.
Gordon
B E
BE
Williams
C
C
Blumenthal
S
S
Watts
J A
JA
Diaz-Buxo
J
J
D000208:Acute Disease; D000818:Animals; D001786:Blood Glucose; D002316:Cardiotonic Agents / Q000627:therapeutic use; D004285:Dogs; D004298:Dopamine / Q000097:blood / Q000627:therapeutic use; D004731:Endotoxins / Q000009:adverse effects; D004837:Epinephrine / Q000097:blood; D004927:Escherichia coli Infections / Q000503:physiopathology / Q000628:therapy*; D005260:Female; D006439:Hemodynamics; D008297:Male; D008567:Membranes, Artificial; D009638:Norepinephrine / Q000097:blood; D006435:Renal Dialysis / Q000295:instrumentation / Q000379:methods*; D012772:Shock, Septic / Q000382:microbiology / Q000503:physiopathology / Q000628:therapy*; D016277:Ventricular Function, Left
D001786:Blood Glucose; D002316:Cardiotonic Agents; D004731:Endotoxins; D008567:Membranes, Artificial; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine