Lipid emulsions - Guidelines on Parenteral Nutrition, Chapter 6.

The infusion of lipid emulsions allows a high energy supply, facilitates the prevention of high glucose infusion rates and is indispensable for the supply with essential fatty acids. The administration of lipid emulsions is recommended within < or =7 days after starting PN (parenteral nutrition) to avoid deficiency of essential fatty acids. Low-fat PN with a high glucose intake increases the risk of hyperglycaemia. In parenterally fed patients with a tendency to hyperglycaemia, an increase in the lipid-glucose ratio should be considered. In critically ill patients the glucose infusion should not exceed 50% of energy intake. The use of lipid emulsions with a low phospholipid/triglyceride ratio is recommended and should be provided with the usual PN to prevent depletion of essential fatty acids, lower the risk of hyperglycaemia, and prevent hepatic steatosis. Biologically active vitamin E (alpha-tocopherol) should continuously be administered along with lipid emulsions to reduce lipid peroxidation. Parenteral lipids should provide about 25-40% of the parenteral non-protein energy supply. In certain situations (i.e. critically ill, respiratory insufficiency) a lipid intake of up to 50 or 60% of non-protein energy may be reasonable. The recommended daily dose for parenteral lipids in adults is 0.7-1.3 g triglycerides/kg body weight. Serum triglyceride concentrations should be monitored regularly with dosage reduction at levels >400 mg/dl (>4.6 mmol/l) and interruption of lipid infusion at levels >1000 mg/dl (>11.4 mmol/l). There is little evidence at this time that the choice of different available lipid emulsions affects clinical endpoints.

Access technique and its problems in parenteral nutrition - Guidelines on Parenteral Nutrition, Chapter 9.

Catheter type, access technique, and the catheter position should be selected considering to the anticipated duration of PN aiming at the lowest complication risks (infectious and non-infectious). Long-term (>7-10 days) parenteral nutrition (PN) requires central venous access whereas for PN <3 weeks percutaneously inserted catheters and for PN >3 weeks subcutaneous tunnelled catheters or port systems are appropriate. CVC (central venous catheter) should be flushed with isotonic NaCl solution before and after PN application and during CVC occlusions. Strict indications are required for central venous access placement and the catheter should be removed as soon as possible if not required any more. Blood samples should not to be taken from the CVC. If catheter infection is suspected, peripheral blood-culture samples and culture samples from each catheter lumen should be taken simultaneously. Removal of the CVC should be carried out immediately if there are pronounced signs of local infection at the insertion site and/or clinical suspicion of catheter-induced sepsis. In case PN is indicated for a short period (max. 7-10 days), a peripheral venous access can be used if no hyperosmolar solutions (>800 mosm/L) or solutions with a high titration acidity or alkalinity are used. A peripheral venous catheter (PVC) can remain in situ for as long as it is clinically required unless there are signs of inflammation at the insertion site.

[Coagulation monitoring of lung embolism using thrombelastography. Resuscitation--Thrombolysis--Massive haemorrhaging]. / Gerinnungsmonitoring mithilfe der Thrombelastographie bei Lungenembolie. Reanimation--Lyse--Massivblutung.

Thrombelastography (TEG) is a bedside method used to determine coagulation parameters such as clot formation, stabilization and lysis. This report describes a case of cardiopulmonary arrest due to fulminant pulmonary embolism in a 42-year-old postpartum patient. We discuss the dynamics of coagulation parameters during CPR and thrombolysis complicated by bleeding, as assessed by TEG.

Surveillance of nosocomial transmission of Candida albicans in an intensive care unit by DNA fingerprinting.

The frequency of nosocomial transmission of the opportunistic fungal pathogen Candida albicans in an intensive care unit was tested by DNA fingerprinting of 91 isolates from 32 hospitalized patients with the mid-repetitive Ca3 DNA probe. This showed that serial isolates of C. albicans from individual patients belonged to genetically distinct strains. In comparison with nosocomial bacterial pathogens, the transmission of C. albicans in an intensive care unit occurred at a much lower frequency. In conclusion, the threat of C. albicans infection does not lie within the hospital, but in commensal isolates. These findings are relevant for infection control practices.

Fish oil-supplemented parenteral diets normalize splanchnic blood flow and improve killing of translocated bacteria in a low-dose endotoxin rat model.

OBJECTIVE: Intestinal ischemia decreases barrier function of the gut and enhances translocation of bacteria and toxins. Several studies indicate that fish oil can modulate prostaglandin formation and thus, regional blood flow and immune function. This study was performed to determine the effects of parenteral diets with omega-3 fatty acids on microcirculation and barrier function of the gut.0 DESIGN: Prospective, randomized, controlled animal study. SETTING: University laboratory. SUBJECTS: A total of 64 male Sprague-Dawley CD rats. INTERVENTIONS AND MEASUREMENTS: For 48 hrs, eight groups of eight rats each received total parenteral nutrition with four different types of lipids. The source of fat in group L was soybean oil only and in group L-M a mixture of soybean oil and medium-chain triglycerides. In groups FO-20 and FO-40, 20% or 40%, respectively, of the soybean oil in group L-M was replaced by fish oil. The other four groups received an additional continuous infusion of endotoxin (0.1 mg/100 g body weight per day) for the last 24 hrs. Blood flow was measured with microspheres, and translocation was determined by microbiological methods and instillation of radioactive-marked bacteria into the gut. MAIN RESULTS: In the animals without fish oil, the endotoxin application reduced the blood flow to the intestine approximately 25%. Animals with fish oil in their diets showed normal values. Translocation of gut bacteria was increased significantly in all endotoxin groups. However, less-viable bacteria could be detected in the animals with fish oil diets in their mesenteric lymph nodes and livers. CONCLUSIONS: In this model, diets enriched with fish oil abolish the endotoxin-induced decrease of nutritive blood flow to the gut and ameliorate the bactericidal defense of the splanchnic region. The lower count of viable bacteria in the fish oil groups is more related to an improved killing of translocated bacteria than a reduction of the translocation rate.

Changes in circulating blood volume after cardiac surgery measured by a novel method using hydroxyethyl starch.

OBJECTIVE: To determine the incidence and extent of postoperative blood volume (BV) changes in patients after elective cardiac surgery using a new method based on dilution of hydroxyethyl-starch. DESIGN: Prospective, clinical, and laboratory investigation. SETTING: University hospital intensive care unit. PATIENTS: A total of thirty-five patients undergoing cardiac surgery requiring cardiopulmonary bypass (CPB). INTERVENTIONS: Perioperative measurements of circulating BV, systemic hemodynamics, lactate, and collection of clinical data. MEASUREMENTS AND MAIN RESULTS: Measurements were made before and 1 to 72 hrs after CPB. The majority of patients undergoing cardiac surgery showed postoperative BV deficits compared with preoperative BV despite marked positive fluid balances after CPB. At 1 hr and 5 hrs after CPB, 18% and 33% of the patients, respectively, had BV deficits in the range of 0.5 L and 1.5 L, and in 3% to 10% of the cases, postoperative BV deficits exceeded 1.5 L. Concomitantly, at 5 hrs after CPB, mean arterial pressure was maximally reduced, and heart rate and lactate levels were maximally elevated. Thereafter, BV began to normalize, and at 24 hrs after CPB, pre- and postoperative mean BV were no longer significantly different. At 48 hrs and 72 hrs, even a BV surplus of more than 1 L could be observed in 6% and 14% of the patients, respectively. CONCLUSIONS: During the first hours after CPB, a high percentage of patients had significantly reduced BV and, concomitantly, showed cardiovascular dysfunction and hyperlactemia. Because hypovolemia is associated with increases of perioperative morbidity and mortality, rapid determination of BV is warranted to guide fluid therapy and optimize treatment in patients undergoing cardiac surgery.

[Prothrombin time and thromboplastin time. On-site measurement of the prothrombin time and activated partial thromboplastin time of surgical patients with laser photometry]. / Prothrombinzeit und Thromboplastinzeit. On-site Messung der Prothrombinzeit und der Aktivierten Partiellen Thromboplastinzeit bei operativen Eingriffen mittels Laserphotometrie.

UNLABELLED: Turnaround time for analysis of prothrombin time (PT) and activated partial thromboplastin time (APTT) by standard laboratory methods ranges between 40 min and several hours. The delay in obtaining the test results limits their clinical utility for treatment of perioperative coagulation disorders and adequate anti-coagulation therapy. In this study, we compared on-site coagulation testing (OCT) of whole blood, which takes about 3 min, with standard laboratory plasma coagulation tests by our institutional laboratory (LAB) to assess the accuracy of the OCT in a clinical setting (abdominal and postcardiac surgery). METHODS: PT of 62 patients with abdominal surgery was measured intra- and postoperatively using both LAB (KC 40, Thromborel S, Centeon) and OCT (CoaguChek Plus, Boehringer Mannheim) systems. APTT was determined by LAB-(KC 40, Pathromtin, Centeon) and OCT-methods in 53 patients who underwent cardiac surgery requiring cardiopulmonary bypass. RESULTS: Linear regression demonstrated a strong and significant (p = 0.0001) correlation of OCT- and LAB-determinations both for PT (r = 0.92) and APTT (r = 0.91). For PT testing, bias analyses showed an agreement between OCT- and LAB-International Normalized Ratio (INR) (bias = 0.24; relative error = 14.6%) that was considered clinically acceptable, with 95% of the INR-differences lying between -0,26 and +0,74 (mean +/- 2 SD). Although commercial APTT-reagents usually differ in their sensitivity to heparin, we also found an acceptable agreement between OCT- and LAB-APTT values (bias = 6.7 s +/- 22 s; mean +/- 2 SD; relative error = 12%). CONCLUSION: On-site coagulation monitoring provides a rapid, convenient, and accurate assessment of coagulation that can both guide specific anti-coagulation therapy and optimize therapy control of coagulation disorders after cardiac and abdominal operations. As a consequence, OCT offers a valuable tool to reduce the inappropriate use of fresh frozen plasma and to improve cost-effectiveness.

Effects of chemically defined structured lipid emulsions on reticuloendothelial system function and morphology of liver and lung in a continuous low-dose endotoxin rat model.

BACKGROUND: This study was undertaken to determine the effect of chemically defined structured lipids on nonspecific host defense and on histologic patterns of liver and lungs compared with a physical mixture of long-chain triglycerides and medium-chain triglycerides in a continuous low-dose endotoxin rat model. METHODS: Forty male Sprague-Dawley rats, divided into four feeding groups (structured lipids, structured lipids+endotoxin, physical mixture, physical mixture+endotoxin), received total parenteral nutrition for 48 hours. During the first part of the study, 24 animals were given an injection of live Escherichia coli labeled with radioactive iron (59Fe) to investigate the function of the reticuloendothelial system. During the second part of the study, the liver and lungs of 16 animals were histologically examined using light and electron microscopy. RESULTS: Despite the similar values in the control groups, the animals receiving structured lipids+endotoxin sequestered a significantly greater percentage of bacteria in the liver and spleen (p < or = .01) and a significantly lesser percentage in the lung (p < or = .05) compared with the animals given physical mixture+endotoxin as part of their diet. Moreover, rats in the physical mixture+endotoxin group showed a microscopically evaluated higher fatty infiltration in the liver than did the structured lipids+endotoxin group. CONCLUSIONS: The results of this study indicate that chemically defined structured lipids reduce fatty infiltration of the liver compared with a physical mixture of the same compounds in an animal model of metabolic stress. They were accompanied by a better function of the reticuloendothelial system and a lesser bacterial sequestration in the lungs.

Chemically defined structured lipids with omega-3 fatty acids maintain splanchnic blood flow in a low-dose continuous endotoxin model.

BACKGROUND: Disturbances of microcirculation and accompanying alterations of oxygen supply are central pathophysiological events in trauma and sepsis. There is evidence that omega-3 fatty acids can modulate prostaglandin formation and thereby regional blood flow. The aim of the study was to determine the effects of chemically defined structured lipids (SL) with omega-3 fatty acids in position sn-2 (MFM) compared to SL with omega-6 fatty acids in position sn-2 (MLM) on cardiac output (CO) and splanchnic blood flow in a low-dose endotoxin (E, 1 mg.kgBW-1.day-1) rat model. MATERIALS AND METHODS: 24 male Sprague Dawley rats, divided in 4 groups (n = 6; MLM, MLM+E, MFM, MFM+E) received for 48 h a total parenteral nutrition. CO and regional blood flow were measured with 85strontium-labelled microspheres (16.5 +/- 0.1 microns). RESULTS: There was a slight rise in CO in the E groups compared to the control groups. Application of E resulted in a marked decrease of intestinal perfusion in the MLM-fed animals, whereas the MFM-fed animals showed only a minimal reduction. This decrease of portal blood flow to the liver was accompanied by an elevation of arterial blood flow to the liver. This compensatory increase in arterial liver blood flow was more pronounced in the MFM-fed animals, resulting in a total liver blood flow which was not different from the control group. CONCLUSIONS: The results of this study implicate that 48 h of intravenous feeding with chemically defined SL with an omega-3 fatty acid in position sn-2 can significantly influence splanchnic bed perfusion in a low-dose endotoxin rat model. The better splanchnic perfusion may be mediated by a shift in prostaglandin production.

[Measuring cardiac output in infants with the Fick principle via oxygen consumption: animal experiment and clinical results]. / Ermittlung des Herzzeitvolumens bei Kleinkindern mittels des Fickschen Prinzipes über den Sauerstoffverbrauch: Tierexperimentelle und klinische Ergebnisse.

UNLABELLED: The aim of this investigation was the validation of cardiac output measurement in children using the method of Fick with the help of a new equipment for the determination of oxygen uptake. METHODS: We compared the cardiac output measured with thermodilution with the calculated cardiac output using the method described by Fick in an animal model (11 dogs, mean weight 20 kg). For determining the cardiac output on Fick's principle oxygen uptake and oxygen content of the arterial and pulmonary-arterial blood was measured in the ventilated dogs. To examine the method of Fick in clinical routine we also determined oxygen uptake and arterial and central venous oxygen content in 5 children in the postoperative period after cardiac surgery with a mean weight of 8.5 kg. Cardiac output in the patients was calculated with the central venous and the pulmonary-arterial oxygen content. The two results were compared. RESULTS: The animal model showed a good correlation of cardiac output measurement on thermodilution and on Fick's method (alpha = 0.001, t-test of significance of correlation). With the method of Fick we found also reliable results at follow up in the clinical routine in the 5 children. The comparison of cardiac output calculated with the central venous oxygen content versus the pulmonary-arterial oxygen content shows a good correlation over all (r = 0.92). In some cases however we found profound differences.

Influence of omega-3 fatty acids on splanchnic blood flow and lactate metabolism in an endotoxemic rat model.

Alteration in regional blood flow is important in the pathogenesis of organ failure during endotoxemia and sepsis. In particular, intestinal ischemia is thought to enhance the translocation of bacteria into the systemic circulation. We used radioactive microspheres to measure the influence of two intravenous (IV) dietary fats (vegetable oil containing high levels of omega-6 fatty acids, and fish oil containing high levels of omega-3 fatty acids) on regional blood flow during low-dose Escherichia coli endotoxin infusion (0.1 mg/100 g body weight [BW]) in a rat model. Despite absence of changes in the cardiac output, blood flow rates to the small and large intestines, stomach, and pancreas, and also to the skin and skeletal muscle were significantly reduced after 18 hours of endotoxin infusion in the rats fed standard vegetable oil. Short-term IV feeding during a period of 40 hours with an isonitrogenous, isocaloric nutrient solution containing fish oil as the only lipid source normalized intestinal perfusion and increased blood flow to the liver and spleen. Low-dose endotoxin infusion also resulted in significant increases in glucose, lactate, and pyruvate concentrations. In comparison to standard vegetable fat emulsion, fish oil significantly reduced these parameters. A second experiment was conducted to measure lactate kinetics. Based on the dilution of U-14C-lactate, fish oil feeding was associated with higher lactate clearance than standard vegetable oil feeding during the endotoxin infusion. We conclude that short-term IV feeding with fish oil improves intestinal perfusion and portal blood flow, improves glucose tolerance, and increases lactate clearance in a low-dose endotoxin rat model.

Mechanisms of protein conservation during xylitol infusion after burn injury in rats: isotope kinetics and indirect calorimetry.

In order to study the mechanisms by which nutrients influence post-trauma metabolism, Sprague-Dawley rats received a 25% full-thickness burn and were randomly assigned to receive 12.5 g kg-1 bodyweight (BW) per day amino acids (AA) only, AA and 14.7 g hydrous glucose kg-1 BW per day or AA and 14.7 g hydrous xylitol kg-1 BW per day. After 4 days of hypocaloric feeding, rats receiving xylitol had a cumulative nitrogen balance of +213 +/- 82 mg N, which was significantly (P less than 0.001) better compared with either the AA with only -493 +/- 61 mg N or the AA and glucose group (P less than 0.01) with -160 +/- 101 mg N. During glucose infusion reduction of insulin-mediated fat oxidation was partially compensated by an increase in glucose oxidation. Xylitol infusions resulted in increased glucose oxidation compared with the amino acid only group without simultaneously reduced fat oxidation. Although glucose and xylitol are calorically similar, their protein sparing properties and metabolic action after injury cannot be based entirely upon their caloric equivalent.

[Artificial feeding]. / Künstliche Ernährung.

An infusion rate above 3 g/kg BW per day glucose leads to a reduction of oxidative metabolism of the energy sources glucose, free fatty acids, and exogenous triglycerides. Simultaneously splanchnic lipogenesis is stimulated and visceral protein utilization inhibited. During the 1st to 4th day after trauma Xylitol (3 g/kg BW per day) is superior to glucose with regard to oxidative metabolism of energy sources and stimulation of visceral protein synthesis. A comparable metabolic effect can be achieved by a glucose/xylitol mixture (1:1); (6 g/kg BW per day) during long-term nutrition.

Phospholipase A--a parameter of sepsis? A comparison of PLA and Stevens' Sepsis Severity Score.

Phospholipase A (PLA) and Sepsis Severity Score (SSS) were measured regularly in 28 patients with sepsis (n = 11), pancreatic operations (n = 7), or multitrauma combined with contused abdominal trauma (n = 10). No linear correlation was found between these two parameters. A statistical correlation could be shown for the paired values PLAmax/SSS or PLA/SSSmax. They lie together above or below their "critical value" of 20 points SSS or 30 U/l PLA (alpha less than 0.05). The evaluation of mortality shows a distinctly higher significance for the SSS (P less than 0.01) in comparison with the PLA (P less than 0.05). In certain cases PLA was the first parameter which could have shown the beginning of a septic process.

Biochemical and hormonal parameters in patients with multiple trauma.

We measured amount, course and duration of different parameters in order to assess metabolic-endocrine changes in patients with multiple trauma and the final outcome. Injures were initially quantified according to the Injury Severity Score. Serum levels of lactate, creatinine, bilirubin, somatomedin and thyroid hormons were measured in 51 patients (39 survivors, 12 deceased patients) for six days following the injury. In addition, neopterin levels were measured in 26 patients (19 survivors, 7 deceased patients). The patients were devided into two groups (survivors vs non-survivors). Global Index Scores and Septic Severity Scores were significantly different at the 1% and 5% level (p less than 0.05 to p less than 0.01). The same statistical differences were shown for lactate, somatomedin, neopterin and thyroid hormones.

Can the outcome after trauma or sepsis be predicted from biochemical or hormonal parameters?

The severity of shock of 36 surgical ICU patients was classified using the Injury Severity Score (N = 20) and the Sepsis Score (N = 16). A great number of laboratory parameters were repeatedly determined on 5 days following the trauma or the onset of septic symptoms. Blood lactate, C-peptide, BUN, osmolality, and thyroid hormones were most closely related to the severity of the disease. This correlation was, however, less pronounced in the trauma than in the septic patients. Lactate and thyroid hormones showed a typical course in the non-survivors and may therefore be valuable as prognostic indices.