Clinical Controversy

Enterococcus species are normal inhabitants of the GI tract, but should empiric treatment of intra-abdominal infections have activity against Enterococcus species? Empiric treatment that covered Enterococcus species in intra-abdominal infections was equivalent to empiric treatment that lacked enterococcal coverage. Routine coverage for Enterococcus is not necessary for patients with community-acquired intra-abdominal infections. However, in patients with nosocomial or high-severity infections, en-terococcal coverage may be warranted.36

Norepinephrine is a potent a-adrenergic agent with less pronounced ^-adrenergic activity. Doses of 0.01 to 3 mcg/kg/min can reliably increase blood pressure with small changes in heart rate or cardiac index. Norepinephrine is a more potent agent


than dopamine in refractory septic shock.

Dopamine is a a- and ^-adrenergic agent with dopa-minergic activity. Low doses of dopamine (1-5 mcg/kg/min) maintain renal perfusion, higher doses (greater than 5

mcg/kg/min) exhibit and ^-adrenergic activity and are frequently utilized to support blood pressure and to improve cardiac function. Low doses of dopamine should not

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be used for renal protection as part of the treatment of severe sepsis. ' '

Dobutamine is a ^-adrenergic inotropic agent that can be utilized for improvement of cardiac output and oxygen delivery. Doses of 2 to 20 mcg/kg/min increase cardiac index; however, heart rate increases significantly. Dobutamine should be considered in septic patients with adequate filling pressure and blood pressure, but low cardiac index. If used in hypotensive patients, dobutamine should be combined with vasopressor therapy.2 , 7,28

Phenylephrine is a fast-acting, short-duration a1 agonist. Phenylephrine has primarily vascular effects, and does not impair cardiac or renal function. Phenyleph-

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rine is useful when tachycardia limits the use of other vasopressors. '

Epinephrine is a nonspecific a and P-adrenergic agonist. Epinephrine can increase cardiac index and produce significant peripheral vasoconstriction. However, it can also increase lactate levels and impair blood flow to the splanchnic system. Because of these undesirable effects, epinephrine should be reserved for patients who fail to respond to traditional therapies.24,27,28

Vasopressin levels are increased during hypotension to maintain blood pressure by vasoconstriction. However, there is a vasopressin deficiency in septic shock. Low doses of vasopressin increase MAP, leading to the discontinuation of vasopressors. However, routine use of vasopressin is not recommended because of lack of evidence of efficacy. Vasopressin is a direct vasoconstrictor without inotropic or chronotropic effects and may result in decreased cardiac output and hepatosplanchnic flow. Vaso-pressin use may be considered in patients with refractory shock despite adequate fluid resuscitation and high-dose vasopressors.24,27,28

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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