ECG-guided central venous catheter positioning: does it detect the pericardial reflection rather than the right atrium?

BACKGROUND AND OBJECTIVE: Although electrocardiography (ECG) guidance of central venous catheters (CVCs) is traditionally thought to detect the entrance into the right atrium (RA), there is little evidence in the literature to confirm this. We previously observed a high incidence of left-sided CVCs abutting the wall of the superior vena cava (SVC), even when the catheters were advanced past the point of increased P-wave amplitude. Our hypothesis was that this ECG amplitude signal is actually detecting the pericardial reflection rather than the RA. The goal of the study was to position catheter tips under ECG guidance outside the RA. METHODS: One-hundred central venous triple-lumen catheters inserted either via the right or the left internal jugular veins, respectively, were analysed in cardiac surgical patients. The position of the catheter tip was ascertained by ECG. METHOD A: A Seldinger guide-wire in the distal lumen served as exploring electrode, the respective insertion depth was recorded. METHOD B: The middle lumen (port opening 2.5 cm from the catheter tip, thus the catheter was advanced more towards the atrium) filled with a saline 10% fluid column served as the exploring electrode, and the insertion depth was recorded again. Descriptive data are given as mean+/-standard deviation. RESULTS: On average, the catheters were advanced by the expected 2+/-0.3 cm using Method B beyond the initial insertion by Method A. All 100 CVCs were finally correctly positioned in the SVC and confirmed by transoesophageal echocardiography. When chest radiography was performed after surgery not a single catheter abutted the lateral wall of the SVC. CONCLUSION: Since both methods detected the same structure, and catheters placed by Method B did not result in intra-atrial CVC tip position, the first increase in P-wave amplitude does correspond to a structure in the SVC, most likely the pericardial reflection.

Post-operative hypoalbuminaemia and procalcitonin elevation for prediction of outcome in cardiopulmonary bypass surgery.

BACKGROUND: Because few studies have addressed postoperative hypoalbuminaemia in relation to hospital mortality, we evaluated this association and the prognostic value of increased procalcitonin (PCT) after cardiopulmonary bypass (CPB) surgery. METHODS: In 454 consecutive patients undergoing CPB, minimal serum albumin, colloid osmotic pressure (COP) and maximal PCT were retrospectively obtained from the 2nd to 10th postoperative day. Receiver operating characteristic (ROC) and multiple regression analyses determined independent predictive strength for 28-day mortality from preoperative albumin, Euroscore, postoperative minimal albumin and COP, and maximal PCT. Cut-off points for the four strongest predictors were calculated by the area under the curve (AUC) in the ROC for the 28-day mortality. RESULTS: Maximal PCT showed the largest AUC (0.85; 95% CI 0.79-0.90) and the highest relative risk (RR 12.17; 95%CI 5.26-28.16; P < 0.001), compared with postoperative albumin (AUC 0.72; 95% CI 0.62-0.81; RR 5.35; 95%CI 2.99-9.56; P < 0.001) and EuroSCORE (AUC 0.73; 95%CI 0.63-0.83; RR 4.48; 95%CI: 1.78-11.28; P < 0.01). By logistic regression, postoperative albumin was the strongest predictor of mortality (odds ratio 0.86; 95% CI 0.84-0.89). Cut-off values for predicting 28-day mortality were found for postoperative albumin and PCT at 17.8 g l(-1) and 2.5 ng l(-1), respectively. A slight but significant inverse correlation between PCT and albumin was found. Patients with albumin less than the cut-off showed significantly higher median values for PCT levels (2.5 vs. 1.0 g l-1), a higher 28-day mortality rate (20.8% vs. 4.5%), and a longer ICU stay (6 vs. 3 days) in comparison with patients with minimal albumin greater than 18 g l(-1). CONCLUSIONS: Post-operative serum albumin <18 g l(-1) and PCT >2.5 ng l(-1) are predictive for a higher 28-day mortality rate in cardiosurgical patients. Both peak PCT and minimal albumin were better outcome predictors than the Euroscore, which better represents the preoperative condition of the patient.

Pretreatment with sufentanil reduces myoclonus after etomidate.

BACKGROUND: Myoclonic movements are a common problem during the induction of general anesthesia with etomidate. We investigated the influence of pretreatment with the opioid sufentanil on the incidence of etomidate-induced myoclonus. METHODS: Forty female patients (ASA physical status I-III) were randomly assigned to receive double-blinded either 0.3 micro g kg-1 of sufentanil or placebo 150 s before the induction of sleep with 0.3 mg kg-1 of etomidate. The patients were observed for any myoclonic movement. Grade of dizziness, breathing frequency, non-invasive blood pressure and heart rate were measured during the study period. RESULTS: None of the 20 patients receiving sufentanil had myoclonic movements after the administration of etomidate, whereas 16 patients in the placebo group (80%) experienced such movements (P<0.01). No cases of apnoea before induction of sleep were seen in the sufentanil group. CONCLUSION: Sufentanil 0.3 micro g kg-1 is an effective and safe drug to reduce myoclonus after etomidate without causing any harmful side-effect.

Early increase of procalcitonin after cardiovascular surgery in patients with postoperative complications.

OBJECTIVE: Type and frequency of postoperative abnormalities were registered after cardiovascular surgery to evaluate the aetiology and diagnostic value of increased concentrations of procalcitonin (PCT) and C-reactive protein (CRP) during the early postoperative period. DESIGN: Prospective, observational study. PATIENTS: Two hundred and eight patients undergoing coronary artery bypass grafting or valve replacement requiring cardiopulmonary bypass were monitored for 7 days postoperatively for various types of infectious or non-infectious complications. Plasma PCT and CRP levels were measured on day 1 and day 2 after surgery and, when increased, until day 7. RESULTS: More patients with PCT above 2 ng/ml on day 1 or 2 (n=55) had postoperative abnormalities (95%) than patients with lower PCT (59%). Specifically, the incidence of three or more criteria of the "systemic inflammatory response syndrome" was 45% versus 4% (area under the curve of the receiver operating characteristic 0.866); positive inotropic support was needed in 65% versus 9% (0.870); respiratory insufficiency (PaO(2)/FIO(2)<200) 38% versus 12% (0.704); proven and suspected bacterial infection 9% versus 1% (0.900) and 24% versus 1% (0.897), respectively. For CRP, the respective areas under the curve were all below 0.63, while all patients had elevated CRP levels, whether they had a complication or not. CONCLUSIONS: Elevated PCT, but not CRP, correlates with evidence of systemic inflammation and other complications early postoperatively after cardiac surgery. Although the PCT levels do not rise as quickly as the criteria of the systemic inflammatory response syndrome appear, they do reflect systemic inflammation. Early identification and quantification of a systemic inflammatory response may help reduce postoperative complications.

Therapeutic options for the treatment of impaired gut function.

Tissue hypoxia, especially in the splanchnic area, is still considered to be an important cofactor in the pathogenesis of multiple organ failure. Therefore, the specific effects of the various therapeutic interventions on splanchnic perfusion and oxygenation are of particular interest. Restoring and maintaining oxygen transport and tissue oxygenation is the most important step in the supportive treatment of patients with sepsis and impaired gut perfusion. Therefore, supportive treatment should be focused on an adequate volume resuscitation and appropriate use of vasoactive drugs. Adequate volume loading may be the most important step in the treatment of patients with septic shock. An elevated oxygen delivery may be beneficial in some patients, but the increase of oxygen delivery should be guided by the measurement of parameters assessing global and regional oxygenation. Forcing an elevation in oxygen delivery by the use of very high dosages of catecholamines can be harmful. Vasopressors should be used for achieving an adequate perfusion pressure. For norepinephrine, no negative effects on gut perfusion have been demonstrated. Epinephrine and dopamine should be avoided because they seem to redistribute blood flow away from the splanchnic region. There are no convincing data yet to support the routine use of low-dose dopamine or dopexamine to improve an impaired gut perfusion. There is even evidence that low-dose dopamine may reduce the mucosal perfusion in the gut in some patients. It has been suggested that dopexamine can improve splanchnic perfusion, but because these effects remain somewhat controversial, a general recommendation for dopexamine to improve gut perfusion is not justified.

Discriminative power of inflammatory markers for prediction of tumor necrosis factor-alpha and interleukin-6 in ICU patients with systemic inflammatory response syndrome (SIRS) or sepsis at arbitrary time points.

OBJECTIVES: To determine the correlations and predictive strength of surrogate markers (body temperature, leukocyte count, C-reactive protein (CRP) and procalcitonin (PCT)) with elevated levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in septic patients on randomly chosen days. DESIGN: Prospective consecutive case series. SETTING: Surgical intensive care unit (ICU) of a university hospital. PATIENTS: Two hundred forty-three patients experiencing ICU stays of longer than 48 h categorized for sepsis according to ACCP/SCCM Consensus Conference criteria. MEASUREMENTS AND MAIN RESULTS: CRP and PCT were both significantly correlated with TNF-alpha and IL-6. Based on the area under the curve (AUC) of the receiver operating characteristic (ROC) curves, predictive capability was highest for PCT (0.846 for TNF-alpha>40 pg/ml and 0.837 for IL-6>500 pg/ml), moderate with CRP (0.744 and 0.748, respectively), and lowest for leukocyte count (0.562 and 0.534, respectively) and body temperature (0.570 and 0.623, respectively). Sensitivity, specificity, positive and negative predictive values and test effectiveness all followed this same pattern of being highest for PCT followed by CRP, with leukocyte count and body temperature being lowest. CONCLUSION: PCT may be an early and better marker of elevated cytokines than the more classic criteria of inflammation.

Dopexamine increases splanchnic blood flow but decreases gastric mucosal pH in severe septic patients treated with dobutamine.

OBJECTIVE: To assess the effects of dopexamine on splanchnic blood flow and splanchnic oxygen uptake in septic patients. DESIGN: A prospective, controlled trial. SETTING: A ten-bed intensive care unit (ICU) in a university hospital. PATIENTS: Twelve patients with severe sepsis (according to the criteria of the 1992 American College of Chest Physicians/Society of Critical Care Medicine consensus conference) being stabilized by volume loading and treated to an elevated oxygen delivery by dobutamine infusion. INTERVENTIONS: Infusion of increasing dosages of dopexamine (0.5, 1.0, 2.0, and 4.0 microg/kg/min). MEASUREMENTS AND MAIN RESULTS: Systemic and splanchnic hemodynamic and oxygen transport parameters as well as gastric mucosal pH (pHi) were measured. A hepatic venous catheter technique with indocyanine green dye dilution was used to determine splanchnic blood flow. Dopexamine increased global and splanchnic oxygen delivery without affecting oxygen consumption (VO2). Splanchnic blood flow increased proportionally to cardiac output, indicating that there was no selective effect of dopexamine on the splanchnic flow. Dopexamine decreased pHi in a dose-dependent fashion in all 12 patients. CONCLUSIONS: In hemodynamically stable, hyperdynamic septic patients being treated with dobutamine, dopexamine has no selective effect on splanchnic blood flow. In fact, a decreased pHi suggests a harmful effect on gastric mucosal perfusion.

Comparison between intrathoracic blood volume and cardiac filling pressures in the early phase of hemodynamic instability of patients with sepsis or septic shock.

PURPOSE: The purpose of this study was to analyze three different variables of cardiac preload; central venous pressure (CVP), pulmonary artery occlusion pressure (PAOP), and intrathoracic blood volume index (ITBVI) that served as the best indicator of cardiac function, that is, cardiac index (C1) or stroke index (SI). MATERIALS AND METHODS: This was a prospective study in 57 critically ill patients with sepsis or septic shock in whom 581 hemodynamic profiles were analyzed. One patient was included a second time after a period of 6 weeks. All patients were sedated and mechanically ventilated. Each patient had a 7.5-Frfive-lumen pulmonary artery catheter (PAC) and a 4-Fr catheter with an integrated thermistor and fiberoptic that was advanced into the descending aorta via a femoral artery sheath. The study was performed in the surgical intensive care unit of a university hospital. RESULTS: Linear regression analysis of the first profile for each case (n = 58) revealed a significant correlation between ITBVI and SI (r = 0.66). For comparison, correlations for PAOP/SI (r = 0.06) and CVP/SI (r = 0.10) were poor. The analysis of all second profiles showed that only the change in ITBVI reflected the change in SI (r = 0.67), whereas PAOP (r = 0.07) and CVP (r = 0.05) failed. Furthermore, a positive change in SI (n = 265) was most often associated with an increase in ITBVI (n = 189, 71.3%), less for PAOP (n = 122, 46.0%) and CVP (n = 137, 51.7%). A reduction in SI (n = 256) was accompanied by a decrease in ITBVI (n = 176, 68.8%), PAOP (n = 119, 46.5%), and CVP (n = 118, 46.1%). An increase in ITBVI (n = 269) was accompanied by an increase in SI in 189 cases (70.3%). In these, PAOP increased only in 91 (48.1%) and CVP in 101 cases (53.4%), respectively. Accordingly, a positive change in PAOP (n = 218) was associated with an increase in SI in 122 cases (56.0%). ITBVI increased in 91 (74.6%) and CVP in 84 (68.9%) of these cases. A decrease in ITBVI (n = 250) was associated with a decrease in SI in 176 cases (70.4%). Decreases in PAOP (n = 89, 50.6%) and CVP (n = 91, 51.7%) did not reflect these changes. However, when PAOP (n = 229) and SI decreased (n = 119, 52.0%), ITBVI decreased in 89 (74.8%) and CVP in 73 cases (61.3%). CONCLUSIONS: In comparison with cardiac filling pressures, ITBVI seems to be the more reliable indicator of cardiac preload in patients with sepsis or septic shock.

Total plasma antioxidant capacity is not always decreased in sepsis.

OBJECTIVE: To compare total plasma antioxidant capacity and selected individual antioxidants in patients with varying degrees of severity of sepsis. DESIGN: A prospective, observational, consecutive case study. SETTING: A 16-bed intensive care unit (ICU) in a university teaching hospital. INTERVENTIONS: None. PATIENTS: Forty-six healthy controls, ten ICU patients, nine patients with systemic inflammatory response syndrome (SIRS), 11 septic patients, and 14 septic shock patients. Plasma was obtained in healthy patients scheduled for minor surgery immediately before anesthesia and in ICU patients within 24 hrs of admittance to the unit or diagnosis of SIRS, sepsis, or septic shock. MEASUREMENTS AND MAIN RESULTS: Using the total peroxyl radical trapping method, we found plasma antioxidant capacity to be lower in septic patients but higher in septic shock patients, as compared with controls. Bilirubin was the greatest contributor to the increase with shock, followed by uric acid. Neopterin also correlated with the peroxyl radical trapping antioxidant parameter values. CONCLUSION: Although total plasma antioxidant capacity is decreased from normal levels in septic patients, an increase in some oxidants contributes to an increased total antioxidant capacity in septic shock patients.

Effect of plasma and LPS on respiratory burst of neutrophils in septic patients.

OBJECTIVE: To compare the respiratory burst of neutrophils in sepsis and control patients using lipopolysaccharide (LPS), autologous plasma, and a combination of the two. DESIGN: Prospective, consecutive case study. SETTING: A 16-bed intensive care unit (ICU) in a university teaching hospital. INTERVENTIONS: None. PATIENTS: Plasma was obtained from 23 healthy patients scheduled for minor surgery immediately prior to induction of anesthesia (controls) and from 23 ICU patients within 24 h of diagnosis of sepsis or septic shock. MEASUREMENTS AND MAIN RESULTS: Respiratory burst was determined by lucigenin chemiluminescence expressed as mean +/- SEM of peak values of relative light units per neutrophil. There were no significant differences between neutrophils of septic patients and controls for the stimuli saline, phorbol myristate acetate, formyl-methionyl-leucyl-phenylalanine, and LPS alone. Septic patients showed a lower respiratory burst than controls (p < 0.05) under the following stimuli: plasma alone (5911 +/- 803 vs 15,397 +/- 3038) and LPS and plasma combined (13,857 +/- 1537 vs 23,026 +/- 2640). However, when stimulated with plasma after priming with LPS, septic patients elicited a higher value than control subjects (11,373 +/- 1758 vs 5987 +/- 1234, p < 0.05). CONCLUSIONS: (1) Some components of the plasma of septic patients may have a profound effect on neutrophil response; (2) plasma as a respiratory burst stimulus differentiates between sepsis and non-sepsis samples better than other common stimuli; (3) precautions must be taken when using plasma together with LPS because of the different response depending on whether LPS-priming precedes the plasma stimulus or both are introduced simultaneously and whether septic or nonseptic plasma is used.

Relevance of routine admission electrocardiograms for psychiatric patients.

OBJECTIVE: To make clinically relevant recommendations for electrocardiogram (ECG) testing among psychiatric patients, the study examined the practice of ordering ECGs for this population. METHODS: The records of 4,045 patients consecutively admitted for psychiatric care to seven community teaching hospitals over one year were examined. The frequency of ECG orders was documented, and abnormal ECG results were grouped into two categories: relevant to psychiatric treatment (ischemia or conduction defects) and incidental to treatment (minor abnormalities and screening abnormalities). For those with abnormalities, additional cardiac follow-up data were recorded. Associations between ECG results and patients' characteristics were analyzed. RESULTS: ECGs were performed for 2,857 (71 percent) of first admissions, of which 2,225 (78 percent) showed neither relevant nor screening abnormalities. Eighteen percent of those tested had relevant abnormalities, most commonly a first-degree atrioventricular block or some evidence of a myocardial infarction. ECG screening abnormalities were found for another 4 percent, primarily left ventricular hypertrophy (3 percent), but no follow-up occurred for 46 percent of these patients. Among patients under 40 years of age, 8 percent had relevant abnormalities, and 3 percent had screening abnormalities. Among patients without apparent cardiac risk, 10 percent had relevant and 3 percent had screening abnormalities. More than half the patients who had a second or third admission during the year had a repeat ECG, even when previous ECGs were normal. CONCLUSIONS: Routine ECG is not an effective treatment or screening tool in this population, and substantial cost savings could result from more selective testing, particularly among young patients, those at low risk, and those with repeat admissions.

A controlled study of leukocyte activation in septic patients.

OBJECTIVE: Qualitative and quantitative evaluation of leukocyte activation in septic patients in comparison to two control groups. DESIGN: A prospective clinical study in which the leukocyte oxidative output of whole blood was measured in three groups of patients. Two chemiluminescence markers (luminol or lucigenin), indicative of either total oxidant output or superoxide production, and three stimuli (opsonized zymosan, formyl-methionyl-leucyl-phenylalanine (fMLP), phorbol myristate acetate) (PMA), representing different pathways of leukocyte activation, were used. Tumor necrosis factor, interleukin-6 and C-reactive protein (TNF, IL-6, and CRP) were determined to evaluate the severity of the inflammatory process. SETTING: Intensive care and surgical units of a university hospital. PATIENTS: Seventy-four healthy patients, ten ICU patients without signs of sepsis or systemic inflammatory response syndrome and 19 septic patients were studied. MEASUREMENT AND MAIN RESULTS: With all three stimuli, whole blood total oxidative output and superoxide production were generally increased in septic patients. This was most likely due to the increased leukocyte numbers in these patients. When the chemiluminescence values were normalized per phagocyte (granulocytes and monocytes), the total oxidative output of septic phagocytes decreased with opsonin and fMLP but increased with PMA, while superoxide output decreased regardless of the stimuli used. TNF, IL-6 and CRP, although increased in septic patients as compared to ICU controls, correlated weakly with oxidant output. CONCLUSIONS: The oxidative output of whole blood was increased in septic patients compared to controls because of elevated leukocyte numbers. However, oxidant output normalized for phagocyte numbers generally decreases during sepsis for most stimuli. Cytokines and CRP do not appear to be associated with the extent of oxidant output during sepsis.

Prescription errors. Legibility and drug name confusion.

Inadvertent drug substitution occurred in several instances in our practices due to the combination of the physician's illegible handwriting on prescriptions and the pharmacist's misinterpretation of subtle clues, which might have prevented the errors. The literature on the legibility of physician handwriting is reviewed. Our specific recommendations include using preprinted prescription pads, training staff assistants who write prescriptions, printing complete directions on each prescription, and aggressively educating each patient about the name and purpose of all drugs being prescribed. Patients are encouraged to bring their medications to each office visit to identify potential errors.

Oral contraceptive failure rates and oral antibiotics.

BACKGROUND: Despite anecdotal evidence of a possibility of decreased effectiveness of oral contraceptives (OCs) with some antibiotics, it is not known whether antibiotic use in dermatologic practices engenders any increased risk of accidental pregnancy. OBJECTIVE: Our purpose was to examine the effect of commonly prescribed oral antibiotics (tetracyclines, penicillins, cephalosporins) on the failure rate of OCs. METHODS: The records from three dermatology practices were reviewed, and 356 patients with a history of combined oral antibiotic/OC use were surveyed retrospectively. Of these patients, 263 also provided "control" data (during the times they used OCs alone). An additional 162 patients provided control data only. RESULTS: Five pregnancies occurred in 311 woman-years of combined antibiotic/OC exposure (1.6% per year failure rate) compared with 12 pregnancies in 1245 woman-years of exposure (0.96% per year) for the 425 control patients. This difference was not significant (p = 0.4), and the 95% confidence interval on the difference (-0.81, 2.1) ruled out a substantial difference (> 2.1% per year). There was also no significant difference between OC failure rates for the women who provided data under both conditions, nor between the two control groups. All our data groups had failure rates below the 3% or higher per year, which are typically found in the United States. CONCLUSION: The difference in failure rates of OCs when taken concurrently with antibiotics commonly used in dermatology versus OC use alone suggests that these antibiotics do not increase the risk of pregnancy. Physicians and patients need to recognize that the expected OC failure rate, regardless of antibiotic use, is at least 1% per year and it is not yet possible to predict in whom OCs may fail.

PIP: Although some antibiotics are assumed to compromise the effectiveness of oral contraceptives (OCs), it is unknown whether the antibiotics used in dermatologic practice are associated with such a risk. To address this issue, a review was conducted in three US dermatologic practices of the records of 356 patients with a history of combined oral antibiotic/OC use in 1990-95 who responded to a follow-up questionnaire. 263 of these patients provided control data during the times they used OCs alone and an additional 162 patients were controls only. There were five pregnancies in 311 woman-years of combined antibiotic/OC exposure (1.6% annual failure rate) compared with 12 pregnancies in 1245 woman-years of exposure among controls (0.96% annual failure rate)--a nonsignificant difference. In addition, there were no significant differences between OC failure rates among women who served as both cases and controls or between the two control groups. All five cases who became pregnant had been taking an antibiotic (microcycline or a cephalosporin) for at least 3 months. Side effects potentially linked to reduced OC effectiveness (e.g., diarrhea, breakthrough menstrual bleeding) were not reported by the women who became pregnant. It is presumed that inter-individual differences in steroid plasma levels are a more important cause of OC failure than concomitant antibiotic therapy.

Epinephrine impairs splanchnic perfusion in septic shock.

OBJECTIVE: To assess the effects of epinephrine on splanchnic perfusion and splanchnic oxygen uptake in patients with septic shock. DESIGN: Prospective, controlled trial. SETTING: University hospital intensive care unit (ICU). PATIENTS: Eight patients with septic shock, according to the criteria of the 1992 American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference, requiring treatment with vasopressors. INTERVENTIONS: We compared in crossover design a 2-hr infusion of epinephrine with dobutamine plus norepinephrine in eight ICU patients with septic shock. Systemic and splanchnic hemodynamics and oxygen transport were measured before and during treatment with epinephrine. MEASUREMENTS AND MAIN RESULTS: There was essentially no effect of epinephrine on the global parameters, except for increased lactate concentrations. There were marked effects on the regional variables; epinephrine caused lower splanchnic flow and oxygen uptake, lower mucosal pH, and higher hepatic vein lactate. CONCLUSION: We conclude that undesirable splanchnic effects on patients in whom that region is particularly fragile should be considered when using epinephrine for septic shock treatment.

The effects of low-dose dopamine on splanchnic blood flow and oxygen uptake in patients with septic shock.

OBJECTIVE: To assess the effects of low-dose dopamine on splanchnic blood flow and splanchnic oxygen uptake in patients with septic shock. DESIGN: Prospective, controlled trial. SETTING: University hospital intensive care unit. PATIENTS: 11 patients with septic shock, diagnosed according the criteria of the 1992 American College of Chest Physicians/Society of Critical Care Medicine consensus conference, who required treatment with norepinephrine. MEASUREMENTS AND MAIN RESULTS: Systemic and splanchnic hemodynamics and oxygen transport were measured before and during addition of low-dose dopamine (3 micrograms/kg per min). Low-dose dopamine and a marked effect on total body hemodynamics and oxygen transport. The fractional splanchnic flow at baseline ranged from 0.15 to 0.57. In 7 patients with a fractional splanchnic flow less than 0.30, low-dose dopamine increased splanchnic flow and splanchnic oxygen delivery and oxygen consumption. In 4 patients with a fractional splanchnic flow above 0.30, low-dose dopamine did not appear to change splanchnic blood flow. CONCLUSION: Low-dose dopamine has a potential beneficial effect on splanchnic blood flow and oxygen consumption in patients with septic shock, provided the fractional splanchnic flow is not already high before treatment.