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E Ruokonen

Publications and source records attributed to E Ruokonen.

At least 55 records · Page 3Linked to original sources
PubMed1997

The effect of dobutamine infusion on splanchnic blood flow and oxygen transport in patients with acute pancreatitis.

OBJECTIVES: To measure the blood flow distribution and oxygen transport in pancreatitis and to evaluate the regional effects of increased systemic blood flow. DESIGN: Nonrandomized controlled trial. SETTING: A general intensive care unit in a tertiary care center. PATIENTS: 10 patients with pancreatitis requiring mechanical ventilation were studied after fluid resuscitation, and for the response to dobutamine, the patients served as their own controls. For the baseline, 11 patients scheduled for elective abdominal surgery served as a control group. INTERVENTIONS: Systemic and regional hemodynamics were measured after fluid resuscitation to predefined hemodynamic endpoints. In patients with pancreatitis, the measurement was repeated after cardiac output had been increased by at least 25% by dobutamine. MEASUREMENTS AND RESULTS: Hepatosplanchnic blood flow was estimated using regional catheterization and the dye dilution method. In patients with pancreatitis, the cardiac index did not differ from that of the control group (3.9 +/- 0.8 vs 4.1 +/- 0.71.min-1.m-2;NS). Accordingly, there was no difference in the splanchnic blood flow (1.1 +/- 0.4 vs 1.2 +/- 0.51.min-1.m-2;NS). Systemic and splanchnic oxygen consumption was increased in patients with pancreatitis (179 +/- 25 vs 147 +/- 27 ml.min-1.m-2, p < 0.05 and 68 +/- 15 vs 49 +/- 19 ml.min-1.m-2, p < 0.05), and systemic and splanchnic oxygen extraction was higher (0.34 +/- 0.08 vs 23 +/- 0.05, p < 0.01 and 0.46 +/- 0.18 vs 0.28 +/- 0.08, p < 0.05, respectively). Dobutamine had inconsistent effects on splanchnic blood flow: in individual patients, splanchnic blood flow even decreased substantially. CONCLUSIONS: In severe pancreatitis, oxygen consumption is increased in the splanchnic region; increased splanchnic oxygen demand is not always met by adequately increased blood flow. Increasing the systemic blood flow with dobutamine does not improve perfusion in the splanchnic bed.

Acute Disease↗
PubMed1997

Preoperative glutamine loading does not prevent endotoxemia in cardiac surgery.

BACKGROUND: The presence of endotoxemia is relatively common in cardiac surgery patients and it may modify the metabolic and hemodynamic responses peri- and postoperatively. Impaired gut fuel metabolism may contribute to the disturbed function and deterioration of the intestinal mucosal barrier and the development of bacterial translocation and endotoxemia. Glutamine may protect the gut mucosal barrier during marginal or insufficient perfusion. METHODS: We studied the effects of glutamine supplementation on endotoxemia and blood levels of tumor necrosis factor (TNF) during and after extracorporeal circulation (ECC) and the effects of endotoxemia on systemic and regional (splanchnic and leg) hemodynamics and metabolism after cardiac surgery. Nineteen elective coronary bypass patients were randomly assigned to receive preoperatively for 12 h either an infusion of glucose and a balanced amino acid solution (AA-group) or a solution containing 1/5 of total nitrogen as alanyl-glutamine (ALAGLN-group). RESULTS: Glutamine and amino acid loading before ECC did not protect from peri- or postoperative endotoxemia. Endotoxemia was detected in 5 vs. 7 of patients during ECC and 6 vs. 5 of patients postoperatively in the ALAGLN-group vs. AA-group, respectively. More than half of the patients at every measurement had an increased level of TNF. There was no consistent difference between the arterial and hepatic vein endotoxin- or TNF-concentrations. Endotoxemia did not modify systemic or regional hemodynamics and metabolism after cardiac operation. CONCLUSION: Glutamine did not prevent endotoxemia during or after cardiac surgery. An increased level of TNF was common and observed also in some patients without endotoxemia. Endotoxemia did not modify regional or whole-body metabolic patterns or hemodynamics.

Amino Acids↗
PubMed1997

Relationship between intra- and postoperative oxygen transport and prolonged intensive care after cardiac surgery: a prospective study.

BACKGROUND: Prolonged intensive care is a rare but serious complication of cardiac surgery. It is required in less than 10% of operated patients but they use more than 30% of all the intensive care resources needed for cardiac surgery. The aim of our study was to describe the clinical course of the patients who need prolonged intensive care following cardiac surgery and to assess whether the intra- and postoperative oxygen transport variables are different in these patients as compared to patients with an uncomplicated course. METHODS: The study patients were divided into two groups according to the length of stay in the intensive care unit (ICU) after the operation: Group I, n = 241, ICU-stay < 5 days and Group II, n 20, ICU-stay > or = 5 days. Hemodynamic and oxygen transport data were prospectively obtained intra- and postoperatively and postoperative organ dysfunctions were recorded. RESULTS: The patients in the prolonged intensive care group tended to be older, have lower ejection fraction and longer cardiopulmonary bypass time. Postoperatively, this group had significantly increased oxygen extraction rate (P = 0.035, repeated measures for ANOVA). In the logistic regression analysis, increased oxygen extraction (31% in Group I vs. 36% in Group II, P < 0.005) at 6 hours after arrival at the intensive care unit had the strongest independent association with the need for prolonged intensive care. CONCLUSIONS: There was no significant relationship between the factors conventionally assumed to be risk factors for prolonged intensive care. Instead, an increase in whole body oxygen extraction, reflecting a mismatch between the whole body oxygen demand and supply, was associated with the need for prolonged intensive care. Oxygen extraction increased to compensate for the reduced oxygen delivery, which in turn was caused by a lower arterial oxygen content.

Adult↗
PubMed1997

Venoarterial CO2 gradient after cardiac surgery: relation to systemic and regional perfusion and oxygen transport.

The difference in CO2 tension between venous and arterial blood (delta PCO2) increases in low-flow states. Therefore, delta PCO2 has been suggested as an additional variable in the monitoring of perfusion. We measured CO2 tensions in arterial, mixed venous, hepatic venous, and femoral venous blood in 42 postoperative cardiac surgery patients. Splanchnic and leg blood flow was measured with dye dilution. Forty-three preoperative abdominal surgery patients served as controls. Systemic and femoral delta PCO2 was increased in cardiac patients, whereas there was no difference in splanchnic delta PCO2 between the groups. In cardiac patients, systemic delta PCO2 correlated well with both splanchnic and femoral delta PCO2 (r2 = .74 and r2 = .56, respectively). Femoral delta PCO2 was higher than splanchnic delta PCO2 (1.27 +/- .44 kPa versus .66 +/- .41; p < .001) after cardiac surgery, but not in the control group. The correlation between delta PCO2 and respective blood flow was weak in the whole body, the splanchnic region, and the leg. When splanchnic blood flow was low, systemic and splanchnic delta PCO2 varied widely. In the cardiac patients with an increased systemic delta PCO2 (> .93 kPa), systemic and regional blood flow was low, but there were no differences in systemic or regional oxygen consumption or lactate levels. After cardiac surgery, high systemic delta PCO2 is associated with marginal systemic and regional perfusion. The adequacy of regional blood flow cannot be assessed on the basis of the systemic delta PCO2.

Arteries↗
PubMed1996

Effect of nasogastric suction and ranitidine on the calculated gastric intramucosal pH.

OBJECTIVE: To study the effect of nasogastric suction and ranitidine on the determination of gastric intramucosal pH (pHi). DESIGN: Prospective study. SETTING: Clinical research unit at a university hospital intensive care department. SUBJECTS: 12 healthy volunteers. INTERVENTIONS: After a 2-h measurement control period a tonometer was connected to nasogastric suction for 2 h, and thereafter ranitidine was given intravenously and gastric pHi measured. MEASUREMENTS AND RESULTS: During each 2-h measurement period gastric PCO2, gastric pHi, and pH gap were determined every 30 min. Luminal pH was measured after insertion of tonometer and at the end of each study period. Neither nasogastric suction nor ranitidine had an effect on the coefficient of variation for either gastric PCO2 or pHi. Compared to control and nasogastric suction periods, after ranitidine mean gastric pHi was higher (control 7.22 +/- 0.08; nasogastric suction 7.23 +/- 0.07; after ranitidine 7.31 +/- 0.06, p < 0.001) mean gastric PCO2 lower (control 6.4 +/- 1.3; nasogastric suction 6.5 +/- 1.3; after ranitidine 5.3 +/- 0.9, p < 0.001) and pH gap lower (control 0.18 +/- 0.08; nasogastric suction 0.17 +/- 0.05; after ranitidine 0.09 +/- 0.06, p < 0.01). Luminal pH increased after ranitidine in each subject. CONCLUSIONS: H2 blockers have no effect on the reproducibility of gastric pHi measurements, but the use of H2 blockers modifies the normal values for gastric pHi in healthy subjects.

Adult↗
PubMed1996

Splanchnic oxygen transport after cardiac surgery: evidence for inadequate tissue perfusion after stabilization of hemodynamics.

OBJECTIVE: To evaluate the adequacy of visceral oxygen transport and gastric pHi after open heart surgery in patients with stable hemodynamics. DESIGN: Nonrandomized control trial. SETTING: A general intensive care unit in a tertiary care center. PATIENTS: Sixteen postoperative cardiac surgery patients were studied after stabilization of systemic hemodynamics. INTERVENTIONS: The effect of dobutamine infusion (6 mu g kg-1 min-1) on systemic and regional oxygen transport was studied in ten patients, with six patients serving as controls. Systemic oxygen consumption was measured by indirect calorimetry and splanchnic and femoral blood flow, by continuous infusion of indocyanine green using regional catheters and gastric mucosal pHi by gastric tonometer. MEASUREMENTS AND RESULTS: Gastric mucosal acidosis was observed in half of the patients. Dobutamine increased cardiac output (3.2 +/- 0.6 vs 4.4 +/- 0.7 l x min-1 x min-2; P <0.05), splanchnic blood flow (0.68 +/- 0.28 vs 0.91 +/- 0.28 l x min-1 x m-2; p <0.05) and femoral blood flow (0.25 +/- 0.08 vs 0.32 +/- 0.11 l x min-1 x m-2; p <0.05). Changes in splanchnic oxygen delivery and consumption were parallel in the two study groups. In response to dobutamine, gastric pHi did not change (7.30 +/- 0.08 vs 7.31 +/- 0.06; NS), while in the control group, gastric pHi tended to decrease (7.32 +/- 0.04 vs 7.28 +/- 0.06; NS). Systemic oxygen consumption increased in response to dobutamine (141 +/- 11 vs 149 +/- 11 ml x min-1 x m-2; P <0.05) but did not change in the control group. CONCLUSIONS: We conclude that a mismatch between splanchnic oxygen delivery and demand may be present despite stabilization of systemic hemodynamics after cardiac surgery. This is suggested by the parallel changes in splanchnic oxygen delivery and consumption. Dobutamine is likely to improve splanchnic tissue perfusion at this phase.

Acidosis↗
PubMed1996

Sodium nitroprusside after cardiac surgery: systemic and splanchnic blood flow and oxygen transport.

BACKGROUND: Vasoactive drugs may interfere with splanchnic blood flow and tissue oxygenation. Sodium nitroprusside (SNP) is widely used in the treatment of postoperative hypertension after cardiac surgery, but the effects of SNP and other vasodilators on splanchnic blood flow have not been well documented. METHODS: The effects of SNP on systemic blood flow, oxygen transport and gastric intramucosal pH (pHi) were studied in 12 patients with arterial hypertension after coronary artery bypass grafting. In 9 of these patients, the effect on regional (splanchnic and leg) blood flow and oxygen transport was also measured. Hemodynamic and regional blood flow responses were measured before and during SNP infusion (mean 2.8 +/- 1.7 micrograms/kg/min, range 0.6-6.3 micrograms/kg/min), when the goal of the vasodilator treatment, mean arterial pressure 70-80 mmHg, had been reached. RESULTS: SNP increased splanchnic (0.65 +/- 0.22 vs. 0.87 +/- 0.37 L.min-1.m-2, P < 0.01) and femoral blood flow (0.15 +/- 0.04 vs. 0.21 +/- 0.06 L.min-1.m-2, P < 0.05) in parallel with cardiac index (2.6 +/- 0.6 vs. 3.3 +/- 0.7 L.min-1.m-2, P < 0.01). Fractional regional blood flows did not change. Mean gastric intramucosal pH decreased slightly (7.40 +/- 0.07 vs. 7.37 +/- 0.06, P < 0.05). Both systemic (420 +/- 85 vs. 495 +/- 90 mL.min-1.m-2, P < 0.05) and femoral oxygen delivery (25 +/- 5 vs. 32 +/- 10 mL.min-1.m-2, P < 0.05) increased, but neither systemic nor regional oxygen consumption changed. CONCLUSIONS: These results suggest that vasoregulation is well preserved during treatment of early postoperative hypertension with SNP, and that SNP has no adverse effects on splanchnic tissue oxygenation.

Antihypertensive Agents↗
PubMed1996

Lactate metabolism and regional lactate exchange after cardiac surgery.

Tissue perfusion is at risk during cardiac surgery and in the immediate postoperative period. The association of low blood flow with metabolic acidosis and accumulation of lactate perioperatively has been well established. With the improvements in cardiopulmonary bypass and overall hemodynamic management, severe peri- and postoperative hypoperfusion has become rare. Despite the rarity of severe postoperative complications, several lines of evidence suggest that episodes of less severe hypoperfusion and borderline tissue oxygenation are relatively common, although generally well tolerated. Measurement of blood lactate levels is widely used to assess the adequacy of tissue perfusion. The interpretation of elevated blood lactate levels is limited by several confounding variables. Acute changes in acid-base balance, interorgan substrate flux, peripheral and visceral tissue perfusion, and hepatic lactate uptake will all influence blood lactate levels and may occur during and after cardiac surgery. Peri- and postoperative hyperlactatemia are rare occurrences and their presence may indicate inadequate tissue perfusion. Based on regional blood flow and lactate exchange measurements, we suggest that hyperlactatemia after cardiac surgery is a sign of inadequate or marginal tissue perfusion of the hepatosplanchnic region, as well as other tissues. In this article we briefly review: a) the normal physiology of lactate metabolism and the various causes of hyperlactatemia; b) studies on lactate levels during and after cardiac surgery; c) the evidence of insufficient or marginal tissue perfusion peri- and postoperatively; and d) the pathophysiology of postoperative increases in blood lactate based on regional lactate kinetics.

Blood Circulation↗
PubMed1995

Estimation of splanchnic blood flow by the Fick principle in man and problems in the use of indocyanine green.

OBJECTIVES: Measurement of splanchnic blood flow is necessary to evaluate the effect of therapeutic interventions on splanchnic tissue perfusion. Systemic indocyanine green (ICG) clearance has been used to estimate splanchnic blood flow, but the results may be compromised by altered hepatic dye extraction. We evaluated the applicability of simultaneous estimation of splanchnic and femoral blood flow by dye dilution and regional blood sampling in intensive care patients. METHODS: 240 simultaneous determinations of regional blood flow were conducted in different patient groups (cardiac surgery, ARDS, pancreatitis, septic shock, preoperative controls). The measurement protocol consists of catheterizations of hepatic vein, femoral artery and vein and primed constant infusion of two different ICG preparations. RESULTS: The method was used successfully in a wide variety of patients. Steady-state dye concentration and sufficient dye extraction was achieved in each group of patients. The coefficient of variation of splanchnic blood flow estimation was 7 +/- 1% and of femoral blood flow estimation 6 +/- 0%. There was a great intra- and interindividual variation of ICG extraction. Use of dobutamine modified the extraction in most patients but did not lessen the performance of the method. ICG extraction was markedly lower and the coefficient of variation of both femoral and splanchnic blood flow markedly higher with propylene glycol-dissolved ICG preparation as compared with the freeze-dried. CONCLUSIONS: The prerequisites for the method of primed, constant infusion of indocyanine green with hepatic vein catheterization are achieved in intensive care patients. The results of splanchnic blood flow estimations based on techniques with peripheral blood sampling should be interpreted with caution, and the use of ICG clearance as a flow-related indicator without the measurement of ICG extraction cannot be justified because of the great variability of dye extraction. Certain indocyanine green preparations may greatly modify the results of the regional blood flow determinations.

Aged↗
PubMed1995

Gastric mucosal pH does not reflect changes in splanchnic blood flow after cardiac surgery.

Despite the widespread use of gastric tonometry to assess splanchnic oxygen transport, no human data are available on the relationship between splanchnic blood flow, splanchnic oxygen delivery and gastric mucosal pH. We have studied the effect of splanchnic blood flow and oxygen delivery on gastric mucosal pHi after cardiac surgery. During the first postoperative hours of intensive care, dopexamine was infused to increase cardiac output in eight patients, while six patients served as controls. Gastric mucosal pH (gastric tonometry), splanchnic blood flow and splanchnic oxygen delivery and consumption (dye dilution) were measured. Dopexamine administration significantly increased splanchnic blood flow (0.72 vs 1.02 litre min-1 m-2) (P < 0.05) and oxygen delivery (117 vs 161 ml min-1 m-2) (P < 0.05) compared with baseline values. However, splanchnic oxygen consumption remained unchanged and gastric mucosal pH levels decreased (7.30 vs 7.25) (P < 0.05). The proportion of splanchnic blood flow of cardiac output did not change in response to infusion of dopexamine, that is dopexamine did not favour blood flow distribution to the splanchnic region. In the control group there were no changes in splanchnic blood flow and oxygen delivery, while splanchnic oxygen consumption increased (36 vs 39 ml min-1 m-2) (P < 0.05) and gastric mucosal pH tended to decrease (7.33 vs 7.29) (ns). We conclude that after cardiac surgery gastric mucosal pH did not reflect changes in splanchnic blood flow and oxygen delivery suggesting heterogeneous or inadequate blood flow distribution within the splanchnic region.

Aged↗
PubMed1995

Dobutamine-induced dissociation between changes in splanchnic blood flow and gastric intramucosal pH after cardiac surgery.

Gastric intramucosal acidosis, a sign of splanchnic tissue hypoxia, is common after cardiac surgery. We tested the hypothesis that an increase in splanchnic blood flow induced by dobutamine improves splanchnic tissue oxygenation after cardiac surgery. We measured changes in gastric intramucosal pH, splanchnic blood flow and oxygen transport in response to increased systemic flow induced by dobutamine (mean 4.4 (range 3.0-7.0) micrograms kg-1 min-1) after coronary artery bypass. We studied 22 stable postoperative patients who were allocated randomly to receive dobutamine (n = 11) or to serve as controls (n = 11). Dobutamine was given also to a separate group with a low cardiac index after operation (n = 6). The end-point was to increase cardiac index by at least 25% and to exceed 2 litre min-1 m-2. Dobutamine consistently increased mean splanchnic blood flow (control 0.6 (SD 0.2) vs 0.7 (0.2) litre min-1 m-2 (P < 0.05); normal cardiac output and dobutamine 0.7 (0.2) vs 1.1 (0.4) litre min-1 m-2 (P < 0.01); low cardiac output and dobutamine 0.4 (0.1) vs 0.7 (0.1) litre min-1 m-2 (P < 0.05)) and oxygen delivery (control 102 (29) vs 111 (28) ml min-1 m-2 (ns); normal cardiac output and dobutamine 106 (27) vs 156 (47) ml min-1 m-2 (P < 0.01); low cardiac output and dobutamine 75 (21) vs 110 (26) ml min-1 m-2 (P < 0.05)) but had no effect on splanchnic oxygen consumption (control 44 (10) vs 49 (10) ml min-1 m-2 (ns); normal cardiac output and dobutamine 45 (12) vs 51 (17) ml min-1 m-2 (ns); low cardiac output and dobutamine 37 (9) vs 40 (9) ml min-1 m-2 (ns)).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Saline PCO2 is an important source of error in the assessment of gastric intramucosal pH.

OBJECTIVE: To determine whether the measurement error of saline PCO2, using blood gas analyzers, is relevant for the interpretation and clinical use of the gastric intramucosal pH measurement. DESIGN: A comparison of four different blood gas analyzers (ABL-520, Ciba Corning, IL-1302, and Nova), using tonometered saline as the reference. SETTING: Clinical laboratory of a university hospital intensive care unit. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The bias and the precision of each blood gas analyzer was determined for measurements of PCO2 in saline samples. These samples had been balanced to PCO2 levels of 30, 45, and 68 torr (4, 6, and 9 kPa, respectively). In addition, the effect of buffering the saline was evaluated. The bias of the PCO2 measurement increased (p < .001) at the higher PCO2 levels. The bias ranged from -5.2 to -25.9 torr (-0.69 to -3.45 kPa) at a PCO2 of 45 torr (6 kPa) and from -5.2 to -33.1 torr (-0.69 to -4.41 kPa) at a PCO2 of 68 torr (9 kPa), and there was a significant (p < .001) analyzer-PCO2 level interaction. The type of the analyzer also influenced the bias (p < .001). The Nova analyzer underestimated the PCO2 by 50% to 60%. The other analyzers underestimated the PCO2 by 5% to 19%. The use of the buffer reduced the bias of all analyzers (p < .001). Based on the precision of the saline PCO2 measurement, a difference in gastric intramucosal pH of 0.06 pH units can be reliably detected at a PCO2 of 45 torr (6 kPa) by all analyzers, with the exception of the Nova analyzer. CONCLUSIONS: Measurement of saline PCO2 is an important source of error in the assessment of gastric intramucosal pH, and the error depends on both the analyzer used and the actual PCO2 level. Direct comparison of pH values obtained by different analyzers is not valid. Changes in gastric intramucosal pH of 0.06 pH units can be detected by most analyzers in the clinically relevant PCO2 level.

Analysis of Variance↗
PubMed1993

Regional blood flow and oxygen transport in septic shock.

OBJECTIVE: To measure the blood flow distribution and regional oxygen transport in hyperdynamic septic shock during hypotension and after correction by vasopressor doses of dopamine or norepinephrine. DESIGN: Prospective, randomized, controlled trial. SETTING: Tertiary care center. PATIENTS: Ten patients with hyperdynamic septic shock (ages ranging from 45.1 +/- 16.6 yrs) and a control group of 11 postoperative cardiac surgery patients (ages ranging from 54.8 +/- 7.9 yrs). INTERVENTIONS: Systemic and regional hemodynamics and oxygen transport were measured in ten patients with hyperdynamic septic shock during hypotension and after vasopressor therapy (norepinephrine or dopamine). Oxygen consumption (VO2) was measured by indirect calorimetry and splanchnic and leg blood flow with indocyanine green infusion. MEASUREMENTS AND MAIN RESULTS: Splanchnic blood flow and VO2 (p < .05) were increased in septic shock during hypotension and during vasopressor therapy. Both dopamine and norepinephrine increased systemic blood flow and VO2 independently of the arterial lactate level. Despite the relatively small changes in systemic oxygen transport, major regional changes occurred in oxygen delivery and VO2, and these changes were unpredictable from systemic changes. CONCLUSIONS: Regional changes in oxygen transport in septic shock cannot be predicted from the changes in the whole body. The increased oxygen demand in the splanchnic region is the main risk factor for splanchnic tissue hypoxia in septic shock.

Adolescent↗
PubMed1993

Regional blood flow and oxygen transport in patients with the low cardiac output syndrome after cardiac surgery.

OBJECTIVE: To assess systemic and regional oxygen transport after open heart surgery in patients with the low cardiac output syndrome who are receiving vasoactive drugs and in patients with normal hemodynamics during spontaneous rewarming. DESIGN: Prospective, nonrandomized controlled trial. SETTING: Tertiary care center. PATIENTS: Sixteen patients aged 53.1 +/- 8.4 yrs were studied after coronary artery bypass operations: ten patients with a cardiac index of < 1.75 L/min/m2 and six control patients with a cardiac index of > 1.75 L/min/m2. INTERVENTIONS: The patients with a cardiac index of < 1.75 L/min/m2 received either dobutamine alone (n = 5) or in combination with nitroprusside (n = 5). The control patients with a cardiac index of > 1.75 L/min/m2 did not receive vasoactive treatment. The systemic oxygen consumption was measured by indirect calorimetry and the regional blood flow was measured by primed continuous infusion of indocyanine green. MEASUREMENTS AND MAIN RESULTS: Both splanchnic and femoral blood flows increased (p < .05) in parallel with cardiac output during vasoactive drug therapy. High splanchnic oxygen extraction in patients with low cardiac index and flow-dependent splanchnic oxygen consumption in some patients indicated marginal splanchnic oxygen delivery. In addition, femoral blood flow was low and oxygen consumption changed in parallel with oxygen delivery in patients with the low cardiac output syndrome. CONCLUSIONS: In low cardiac output syndrome after cardiac surgery, splanchnic oxygen delivery was marginal and was maintained at the expense of peripheral oxygen delivery. Dobutamine, both alone and in combination with sodium nitroprusside, improved splanchnic oxygen delivery.

Body Temperature↗
PubMed1992

Oxygen transport in septic shock.

Septic shock is an acute impairment of tissue perfusion, characterized by hypotension, low systemic vascular resistance and increased blood levels of lactate. Myocardial dysfunction is common despite hyperdynamic circulation, and may limit the patient's ability to respond to increased tissue oxygen demand. The treatment of hypotension necessitates the use of sympathomimetic drugs, which may compromise regional tissue perfusion despite overall stabilization of hemodynamics. The disproportionately high splanchnic oxygen demand in sepsis makes the splanchnic region susceptible to tissue hypoxia, which may contribute to the development of multiple organ failure in septic shock. Since the changes in regional oxygen transport do not necessarily parallel changes in systemic oxygen transport, the effects of vasoactive drugs on regional blood flow in sepsis should be studied in more detail.

Hemodynamics↗
PubMed1991

Septic shock and multiple organ failure.

OBJECTIVE: To assess the frequency and mortality rates of septic shock in ICU patients and the clinical course of multiple organ failure associated with septic shock. DESIGN: Retrospective case survey. SETTING: Tertiary care center. PATIENTS: During a 2-yr period, 2,469 consecutive intensive care patients were studied regarding the frequency and hospital mortality rates of septic shock. A subset of 1,311 patients was further analyzed for the occurrence of organ system failures within 48 hrs of the onset of septic shock and again 4 to 7 days later. MEASUREMENTS AND MAIN RESULTS: The frequency rate of septic shock was 1.9% (n = 48), with a mortality rate of 72.9% (n = 35) in patients with septic shock. Deaths due to septic shock represented 14.6% of all deaths in the ICU during the study period. Eighteen patients died within 72 hrs of the onset of septic shock. Refractory hypotension was the cause of death in 15 of these 18 patients. Beyond 72 hrs, multiple organ failure accounted for eight of 17 deaths. The mean +/- SD number of organ systems failing at 48 hrs was 3.3 +/- 1.3 in survivors and 4.0 +/- 1.1 in nonsurvivors, and at 4 to 7 days was 2.1 +/- 1.5 in survivors and 4.0 +/- 1.5 in nonsurvivors (p less than .05). None of the specific organ system failures had prognostic value. The number of organ system failures was not related to the duration of hypotension, but had a weak correlation (r2 = .26, p less than .05) with the duration of vasoactive treatment at 4 to 7 days. The prolonged need for norepinephrine therapy was associated with an increased occurrence of renal failure. Thirty (62.5%) patients had positive blood cultures and a mortality rate similar to the mortality rate of patients with negative blood cultures. Patients with negative blood cultures died more often with hypotension (p less than .02). CONCLUSIONS: Septic shock is a major cause of death in intensive care patients. Refractory hypotension is a main cause of early deaths. Later on, multiple organ failure becomes the primary clinical problem and cause of mortality.

Adult↗