Sepsis hemodynamic effects

The hallmark of the hemodynamic effect of sepsis is the hyperdynamic state characterized by high cardiac output and an abnormally low systemic vascular resistance. 

Equine Veterinary Education 8 8-12 Ecke P, Hodgson D R, Rose R J 1998 Induced diarrhoea in horses. Part 2 Response to administration of an oral rehydration solution. Veterinary Journal 155 161-170 Fanconi S, Burger R, Ghelfi D et al 1993 Hemodynamic effects of sodium bicarbonate in critically III neonates. Intensive Care Medicine 19 65-69 Fink M 1997 Cytopathic hypoxia in sepsis. Acta Anaesthesiologic Scandinavica Supplementum 110 87-95... 

Tumor Necrosis Factor Alpha Tumor necrosis factor alpha (TNFa) is an inflammatory cytokine and interleukin that is involved in the genesis of sepsis, arthritis, and a variety of other inflammatory states (see Chapter 22). It also has hemodynamic effects and reduces ventricular performance. It is also a common signaling molecule. Assays for it or its receptor have been developed, but the failure of recent therapeutic trials has led to concern about how to properly interpret the high levels seen in patients with CHF and coronary heart disease. At present, there are no standardized assays and no reference interval studies or consistent assay validations. 

Dopamine often is recommended as the initial catecholamine in sepsis because it increases blood pressure by increasing myocardial contractility and vasoconstriction. Dopamine has been described to have dose-related receptor activity at DAj-, DA2-, fi -, and i-receptors. Unfortunately, this dose-response relationship has not been confirmed in critically ill patients. In patients with septic shock, there is a great overlap of hemodynamic effects even at doses as low as 3 mcg/kg per minute. Tachydysrhythmias are common owing to the release of endogenous norepinephrine by dopamine entering the sympathetic nerve terminal. Dopamine may increase the PAOP through pulmonary vasoconstriction. This drug also may depress ventilation and worsen hypoxemia in patients dependent on the hypoxic ventilatory drive. 

The hallmark of the hemodynamic effect of sepsis is the hyperdynamic state characterized by high cardiac output and an abnormally low systemic vascular resistance (SVR). TNF-a and endotoxin directly depress cardiovascular function. Endotoxin depresses left ventricular function independent of changes in left ventricular volume or vascular resistance. 

P. Rademiacher. B. Santak. H. Slrobaeh, K. Sehrdr. and J. Tamow. Pal emulsions containing medium chain triglycerides in patients with sepsis syndrome effects on pulmonary hemodynamics and gas exchange. Intensive Care Med. 18 231-234, 1992. 

It has been concluded that hemosorption with Polymyxin hemosorbent Lyposorb is an effective method of treatment of abdominal sepsis caused by gram-negative flora. HS eliminates endotoxins and stabilizes hemodynamics. The use of Polymyxin hemosorbent Lyposorb for hemosorption in the integrated therapy of patients with abdominal sepsis significantly improves results of treatment. 

Holbeck S, Grande P-0 2000 Effects on capillary fluid permeability and fluid exchange of albumin, dextran, gelatin, and hydroxyethyl starch In cat skeletal muscle. Critical Care Medicine 28 1089-1095 Hollenberg S M, Ahrens T S, Astiz M E 1999 Practice parameters for hemodynamic support of sepsis in adult patients in sepsis. Critical Care Medicine 27 639-660... 

Day NP, Phu NH, Mai NT, et al. Effects of dopamine and epinephrine infusions on renal hemodynamics in severe malaria and severe sepsis. Crit Care Med 2000 28 1353-1362. 

Dopexamine (Dopacard) is a synthetic analog related to dopamine with intrinsic activity at dopamine Dj and D2 receptors as well as at P2 receptors it may have other effects such as inhibition of catecholamine uptake. It appears to have favorable hemodynamic actions in patients with severe CHF, sepsis, and shock. In patients with low cardiac output, dopexamine infusion significantly increases stroke volume with a decrease in systemic vascnlar resistance Tachycardia and hypotension can occnr, bnt nsnally only at high infusion rates. 

A common cause of death in Western Europe is chronic heart failure. Measures for its severity are hemodynamic parameters, including stroke volume (SV). Until now, the gold standard for measuring these parameters is the thermodilution technique using pulmonary artery catheters. However, the risks of estimating cardiac output via catheters include infections, sepsis and arrhythmias, as well as increased morbidity and mortality. An alternative technique to assess SV easily and cost-effectively is the use of impedance cardiography (ICG). 

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