Body composition and muscle strength at the end of ICU stay are associated with 1-year mortality, a prospective multicenter observational study

BACKGROUND & AIMS

After a prolonged intensive care unit (ICU) stay patients experience increased mortality and morbidity. The primary aim of this study was to assess the prognostic value of nutritional status, body mass composition and muscle strength, as assessed by body mass index (BMI), bioelectrical impedance analysis (BIA), handgrip (HG) test, and that of the biological features to predict one-year survival at the end of a prolonged ICU stay.

METHODS

This was a multicenter prospective observational study. Survivor patients older than 18 years with ICU length of stay >72 h were eligible for inclusion. BIA and HG were performed at the end of the ICU stay. Malnutrition was defined by BMI and fat-free mass index (FFMI). The primary endpoint was one-year mortality. Multivariable logistic regression was performed to determine parameters associated with mortality.

RESULTS

572 patients were included with a median age of 63 years [53.5; 71.1], BMI of 26.6 kg/m2 [22.8; 31.3], SAPS II score of 43 [31; 58], and ICU length of stay of 9 days [6; 15]. Malnutrition was observed in 142 (24.9%) patients. During the 1-year follow-up after discharge, 96 (18.5%) patients died. After adjustment, a low HG test score (aOR = 1.44 [1.11; 1.89], p = 0.01) was associated with 1-year mortality. Patients with low HG score, malnutrition, and Albuminemia <30 g/L had a one-year death rate of 41.4%. Conversely, patients with none of these parameters had a 1-year death rate of 4.1%.

CONCLUSION

BIA to assess FFMI, HG and albuminemia at the end of ICU stay could be used to predict 1-year mortality. Their ability to identify patients eligible for a structured recovery program could be studied.

A randomized trial of supplemental parenteral nutrition in underweight and overweight critically ill patients: the TOP-UP pilot trial

Background

Nutrition guidelines recommendations differ on the use of parenteral nutrition (PN), and existing clinical trial data are inconclusive. Our recent observational data show that amounts of energy/protein received early in the intensive care unit (ICU) affect patient mortality, particularly for inadequate nutrition intake in patients with body mass indices (BMIs) of <25 or >35. Thus, we hypothesized increased nutrition delivery via supplemental PN (SPN) + enteral nutrition (EN) to underweight and obese ICU patients would improve 60-day survival and quality of life (QoL) versus usual care (EN alone).

Methods

In this multicenter, randomized, controlled pilot trial completed in 11 centers across four countries, adult ICU patients with acute respiratory failure expected to require mechanical ventilation for >72 hours and with a BMI of <25 or ≥35 were randomized to receive EN alone or SPN + EN to reach 100% of their prescribed nutrition goal for 7 days after randomization. The primary aim of this pilot trial was to achieve a 30% improvement in nutrition delivery.

Results

In total, 125 patients were enrolled. Over the first 7 post-randomization ICU days, patients in the SPN + EN arm had a 26% increase in delivered calories and protein, whereas patients in the EN-alone arm had a 22% increase (both p < 0.001). Surgical ICU patients received poorer EN nutrition delivery and had a significantly greater increase in calorie and protein delivery when receiving SPN versus medical ICU patients. SPN proved feasible to deliver with our prescribed protocol. In this pilot trial, no significant outcome differences were observed between groups, including no difference in infection risk. Potential, although statistically insignificant, trends of reduced hospital mortality and improved discharge functional outcomes and QoL outcomes in the SPN + EN group versus the EN-alone group were observed.

Conclusions

Provision of SPN + EN significantly increased calorie/protein delivery over the first week of ICU residence versus EN alone. This was achieved with no increased infection risk. Given feasibility and consistent encouraging trends in hospital mortality, QoL, and functional endpoints, a full-scale trial of SPN powered to assess these clinical outcome endpoints in high-nutritional-risk ICU patients is indicated—potentially focusing on the more poorly EN-fed surgical ICU setting.

Trial registration

NCT01206166

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-017-1736-8) contains supplementary material, which is available to authorized users.

Lipid emulsions for parenteral nutrition in critical illness

Critical illness is a life-threatening multisystem process that can result in significant morbidity and mortality. In most patients, critical illness is preceded by a physiological deterioration, characterized by a catabolic state and intense metabolic changes, resulting in malnutrition and impaired immune functions. In this context, parenteral lipid emulsions may modulate inflammatory and immune reactions, depending on their fatty acid composition. These effects appear to be based on complex modifications in the composition and structure of cell membranes, through eicosanoid and cytokine synthesis and by modulation of gene expression. The pathophysiological mechanisms underlying these fatty acid-induced immune function alterations in critical ill patients are however complex and partially understood. Indeed, despite a very abundant literature, experimental and clinical data remain contradictory. The optimization of lipid emulsion composition thus represents a major challenge for clinical medicine, to adequately modulate the inflammatory pathways. In the present review, we first address the metabolic response to aggression, the effects of parenteral lipid emulsions on inflammation and immunity, and finally the controversial place of these lipid emulsions during critical illness. The analysis furthermore highlights the pathophysiological mechanisms underlying the differential effects of lipid emulsions and their potential for improving the handling of critically ill patients.

Similar but not the same: insights into the evolutionary history of paralogous sex-determining genes of the dwarf honey bee Apis florea

Studying the fate of duplicated genes provides informative insight into the evolutionary plasticity of biological pathways to which they belong. In the paralogous sex-determining genes complementary sex determiner (csd) and feminizer (fem) of honey bee species (genus Apis), only heterozygous csd initiates female development. Here, the full-length coding sequences of the genes csd and fem of the phylogenetically basal dwarf honey bee Apis florea are characterized. Compared with other Apis species, remarkable evolutionary changes in the formation and localization of a protein-interacting (coiled-coil) motif and in the amino acids coding for the csd characteristic hypervariable region (HVR) are observed. Furthermore, functionally different csd alleles were isolated as genomic fragments from a random population sample. In the predicted potential specifying domain (PSD), a high ratio of πN/πS=1.6 indicated positive selection, whereas signs of balancing selection, commonly found in other Apis species, are missing. Low nucleotide diversity on synonymous and genome-wide, non-coding sites as well as site frequency analyses indicated a strong impact of genetic drift in A. florea, likely linked to its biology. Along the evolutionary trajectory of ~30 million years of csd evolution, episodic diversifying selection seems to have acted differently among distinct Apis branches. Consistently low amino-acid differences within the PSD among pairs of functional heterozygous csd alleles indicate that the HVR is the most important region for determining allele specificity. We propose that in the early history of the lineage-specific fem duplication giving rise to csd in Apis, A. florea csd stands as a remarkable example for the plasticity of initial sex-determining signals.

Assessment of hemodynamic efficacy and safety of 6% hydroxyethylstarch 130/0.4 vs. 0.9% NaCl fluid replacement in patients with severe sepsis: the CRYSTMAS study

Introduction

Inadequate initial treatment and delayed hemodynamic stabilization (HDS) may be associated with increased risk of death in severe sepsis patients.

Methods

In order to compare the hemodynamic efficacy and safety of 6% HES 130/0.4 and NaCl 0.9% for HDS in patients with severe sepsis, we designed a prospective, multicenter, active-controlled, double-blind, randomized study in intensive care units.

Results

174 out of 196 patients reached HDS (88 and 86 patients for HES and NaCl, respectively). Significantly less HES was used to reach HDS vs. NaCl (1,379 ±886 ml in the HES group and 1,709 ±1,164 ml in the NaCl group (mean difference = -331± 1,033, 95% CI -640 to -21, P = 0.0185). Time to reach HDS was 11.8 10.1 hours vs. 14.3 ±11.1 hours for HES and NaCl, respectively. Total quantity of study drug infused over four consecutive days, ICU and hospital LOS, and area under the curve of SOFA score were comparable. Acute renal failure occurred in 24 (24.5%) and 19 (20%) patients for HES and NaCl, respectively (P = 0.454). There was no difference between AKIN and RIFLE criteria among groups and no difference in mortality, coagulation, or pruritus up to 90 days after treatment initiation.

Conclusion

Significantly less volume was required to achieve HDS for HES vs. NaCl in the initial phase of fluid resuscitation in severe sepsis patients without any difference for adverse events in both groups.

ClinicalTrials.gov

NCT00464204

Continuous glucose monitoring in cystic fibrosis patients according to the glucose tolerance

Cystic fibrosis (CF) is associated with a long preclinical state of abnormal glucose tolerance. The aim of this study was (i) to evaluate the profile of glucose tolerance in young adults with CF and (ii) to compare these results with those obtained by a continuous subcutaneous glucose monitoring (CGMS). CF subjects with fasting glycemia inferior to 126 mg/dl were included in the study. An oral glucose tolerance test (OGTT) identified the subjects either with a normal glucose tolerance (NGT), or impaired glucose tolerance (IGT), or diabetes. CGMS (Medtronic) was performed during 3 days to analyze mean glucose level, high glucose excursions, and glucose area under the curve (AUC). Forty-nine patients were included in the study. NGT (n=22), IGT (n=17), and diabetes groups (n=10) were comparable except with regard to age and BMI (p<0.001). HbA1c values in diabetes group were significantly higher (p<0.001) than in NGT and IGT groups. CGMS revealed peaks of glucose values superior to 200 mg/dl at least once after a meal in 8 patients (36%) with NGT, in 9 patients (52%) with IGT, and in all patients with diabetes (p<0.01). Mean CGMS glucose and glucose AUC values increased in patients with diabetes compared to patients with NGT and IGT (p<0.05). Peak of CGMS glucose reached 182+/-60 mg/dl in NGT group despite the normal glucose profile at OGTT. In conclusion, CGMS revealed pathological glucose excursions not only in patients with impaired glucose tolerance at OGTT but also in patients with a normal glycemic profile. CGMS could be a useful tool for the early detection of hyperglycemia in patients with CF.

L-alanyl-L-glutamine dipeptide-supplemented total parenteral nutrition reduces infectious complications and glucose intolerance in critically ill patients: the French controlled, randomized, double-blind, multicenter study

OBJECTIVE

Glutamine (Gln)-supplemented total parenteral nutrition (TPN) improves clinical outcome after planned surgery, but the benefits of Gln-TPN for critically ill (intensive care unit; ICU) patients are still debated.

DESIGN

Prospective, double-blind, controlled, randomized trial.

SETTING

ICUs in 16 hospitals in France.

PATIENTS

One-hundred fourteen ICU patients admitted for multiple trauma (38), complicated surgery (65), or pancreatitis (11).

INTERVENTIONS

Patients were randomized to receive isocaloric isonitrogenous TPN via a central venous catheter providing 37.5 kcal and 1.5 g amino acids.kg-1.day-1 supplemented with either L-alanyl-L-glutamine dipeptide (0.5 g.kg-1.day-1; Ala-Gln group, n=58) or L-alanine+L-proline (control group, n=56) over at least 5 days.

MEASUREMENTS AND MAIN RESULTS

Complicated clinical outcome was defined a priori by the occurrence of infectious complications (according to the criteria of the Centers for Disease Control and Prevention), wound complication, or death. The two groups were compared by chi-square test on an intention-to-treat basis. The two groups did not differ at inclusion for type and severity of injury (mean simplified acute physiology score II, 30 vs. 30.5; mean injury severity score, 44.9 vs. 42.3). Similar volumes of TPN were administered in both groups. Ala-Gln-supplemented TPN was associated with a lower incidence of complicated outcome (41% vs. 61%; p<.05), which was mainly due to a reduced infection rate per patient (mean, 0.45 vs. 0.71; p<.05) and incidence of pneumonia (10 vs. 19; p<.05). Early death rate during treatment and 6-month survival were not different. Hyperglycemia was less frequent (20 vs. 30 patients; p<.05) and there were fewer insulin-requiring patients (14 vs. 22; p<.05) in the Ala-Gln group.

CONCLUSIONS

TPN supplemented with Ala-Gln dipeptide in ICU patients is associated with a reduced rate of infectious complications and better metabolic tolerance.

Lipids in the nutritional support of the critically ill patients

PURPOSE OF REVIEW

This review reports recent findings on lipid use in artificial nutrition in patients with acute respiratory failure or severe sepsis or undergoing major surgery. It examines current knowledge of fatty acid safety, biologic effects, and the impact on patients' morbidity and mortality. The newly emerging area of genotypic influence and timing of immunonutrition is also discussed.

RECENT FINDINGS

In acute respiratory distress syndrome, the debate concerning the use of long-chain fatty acids as opposed to physical mixtures of medium- and long-chain fatty acids, specifically regarding their effects on gas exchange and pulmonary hemodynamics, still remains unresolved. By contrast, providing fish oil fatty acids (mainly eicosapentaenoic and docosahexaenoic acids) and/or gamma-linolenic acid, seems to decrease harmful excessive inflammatory/immune activation and to improve clinical outcome. Similar effects, although not conclusively demonstrated, have been reported for n-3 fatty acid-enriched lipid emulsions in patients with sepsis. Few recent studies examined the impact of n-3 fatty acid-enriched enteral formulas on patients undergoing major surgery. Most studies focused on intravenous fish oil and suggest beneficial effects both on inflammatory/immune parameters and patient outcome. Studies suggest that lipid use in critically ill patients may be improved by increased knowledge of genetic determinants of severity of injury and response to therapeutic agents as well as by the development of tools that allow better timing of immunonutritional intervention.

SUMMARY

Overall, lipids, in particular n-3 fatty acids, emerge as powerful nutrients with pharmacologic properties potentially improving prognosis in critically ill patients. However, heterogeneity in study design makes the interpretation of available studies difficult. Consequently, larger prospective, randomized, double-blind trials with comparable methodologies are necessary for detailed evaluation of the pharmacologic impact of lipids. In addition, a better knowledge of the influence of genotypic variation and postinjury inflammatory/immune temporal patterns may improve our current therapeutic use of various fatty acids.

[Treatment of malnutrition: parenteral nutrition]

Malnutrition affects a high number of hospitalized patients and worsen their outcome. Nutritional support is then essential and the appropriate way is in the most cases represented by dietary supplementation or enteral feeding. Parenteral nutrition may be required in some cases of particularly severe malnutrition. Its efficiency is widely proved and parenteral nutrition provides an adequate nutritional support when oral or enteral nutrition is impossible or insufficient. The energy supply by a mixture of nutrients in multicompartiment bags is now routinely accepted and all-in-one mixtures facilitate home parenteral nutrition. The strict respect for indications and for procedures during use should reduce the parenteral nutrition-induced complications. The benefits of this therapy are obtained with a carefully trained team but the most undernourished patients should not be deprived of its advantages.

The prognostic value of nutritional and inflammatory indices in critically ill patients with acute respiratory failure

In critically ill patients suffering from acute respiratory failure, weaning from ventilatory assistance is a key survival factor in intensive care units (ICU). The aim of this study was to provide deeper insight into laboratory methods allowing improved monitoring of that critical period. Eighty-three ICU patients (mean age 63.9 years), classified according to the Second Acute Physiology and Chronic Health Evaluation criteria, were submitted to mechanical ventilation, antibiotherapy and nutritional support. Weaning attempts required degressive pressure support ventilation. The biological status of the patients was assessed by the serial measurement of inflammatory (C-reactive protein and alpha1-acid glycoprotein) and of nutritional (albumin and transthyretin) indicators whose aggregation yields a prognostic inflammatory and nutritional index (PINI). Statistical analyses compared ventilatory and biological data recorded on admission and at the time of extubation. Results showed that vital capacity and plasma concentrations of albumin and transthyretin rose, whereas rapid shallow breathing index, C-reactive protein and PINI values declined during the tested period. Persistent low transthyretin concentrations were predictive of lethality while increased values were associated with improved ventilatory performances. The PINI scoring formula worked as an independent predictor of the weaning trial outcome. The study underlined the value of the PINI system for the successful management of the weaning procedure.

Specific developmental gene silencing in the honey bee using a homeobox motif

Manipulating the expression of genes in species that are not currently used as genetic models will provide comparative insights into the evolution of gene functions. However the experimental tools in doing so are limited in species that have not served as models for genetic studies. We have examined the effects of double stranded RNA (dsRNA) in the honey bee, an insect with considerably basic scientific interest. dsRNA derived from a 300 bp stretch of the E30 homeobox motif was injected into honey bee embryos at the anterior pole in the preblastoderm stage. We found that the dsRNA fragment successfully disrupted the protein expression of the target gene throughout the whole embryo. The disruption caused deficient phenotypes similar to known loss of function mutants of Drosophila engrailed, whereas embryos injected with nonsense dsRNA showed no abnormalities. We show that the large size of the honey bee egg (D: 0.3 mm, L: 1.6 mm) and the long preblastoderm stage (11-12 h) can be exploited to generate embryos with partial disruption of gene function, which may provide an elegant alternative to classical chimeric analyses. This is the first report of targeted disruption of gene function in the honey bee, and the results prove that the chosen target gene is a functional ortholog to engrailed in Drosophila.

Fine scale mapping in the sex locus region of the honey bee (Apis mellifera)

Isolating an unknown gene with fine-scale mapping is possible in a "non-model" organism. Sex determination in honey bees consists of a single locus (sex locus) with several complementary alleles. Diploid females are heterozygous at the sex locus, whereas haploid males arise from unfertilized eggs and are hemizygous. The construction of specific inbred crosses facilitates fine scale mapping in the sex locus region of the honey bee. The high recombination rate in the honey bee reduces the physical distance between markers compared with model organisms and facilitates a novel gene isolation strategy based on step-wise creation of new markers within small physical distances. We show that distances less than 25 kb can be efficiently mapped with a mapping population of only 1000 individuals. The procedure described here will accelerate the mapping, analysis and isolation of honey bee genes.

Blood polyamine levels after oral ornithine load, a diagnostic marker of hyperproliferative premalignant and malignant stages in a model of colon carcinogenesis

This study was performed to determine whether a single oral dose of ornithine (Orn), the substrate of ornithine decarboxylase (ODC), increases blood concentrations of polyamines premalignant stage, and whether blood polyamine levels could be used as predictive markers of cancer development. Male Wistar rats were divided into two groups, control and 1,2-dimethylhydrazine (DMH)-treated rats. DMH (20 mg/kg body weight) was injected intraperitoneally once weekly for 10 weeks. Five, 7, and 10 weeks after the last injection when premalignant aberrant crypt foci have developed in the colon, blood levels of putrescine (PUT), spermidine (SPD), and spermine (SPM) were estimated before and after an oral load of ORN. The results showed that after a single oral load of Orn, blood PUT, but not SPD and SPM, concentrations were significantly higher in DMH-treated rats compared with control rats, indicating enhancement of ODC activity. These results support the view that the increased blood concentration of PUT after administration of Orn may be a useful marker to detect hyperproliferative premalignant and malignant stages of cancer development.

Promotion of intestinal carcinogenesis by dietary methionine

The metabolism of the polyamines spermidine and spermine is known to be enhanced in rapidly proliferating cells. Methionine is a precursor of the aminopropyl moieties of these amines. Therefore, it was of interest to study the effects of a methionine supplemented diet on polyamine metabolism and preneoplastic changes occurring in the intestinal tract of rats treated with the chemical carcinogen azoxymethane (AOM). Adult Wistar rats received 15 mg AOM/kg body wt (i.p.) once each week for 2 weeks. Thereafter, the rats were randomly divided into two groups and received controlled isoenergetic diets containing the same amount of folate, choline and vitamin B12 during 12 weeks: one group was kept on a standard diet; the other was fed the same diet, except that 1% L-methionine was added at the expense of carbohydrates. After 12 weeks, the administration of the methionine-supplemented diet stimulated the turnover rate of ileal epithelial cells, indicating enhanced crypt cell proliferation. Furthermore, in this group, a 2-fold increase in the number of aberrant hyperproliferative crypts and the appearance of tumors was observed in the colon. These effects were accompanied by the increased formation of spermidine and spermine due to the enhancement of S-adenosylmethionine decarboxylase activity and by the upregulation of Cdx-1, a homeobox gene with oncogenic potentials. The experimental data do not support the view of a chemopreventive effect of dietary methionine supplementation on intestinal carcinogenesis in rats, even at an early phase of preneoplastic development, but rather suggest that methionine promotes intestinal carcinogenesis.

Functional and metabolic changes in intestinal mucosa of rats after enteral administration of ornithine alpha-ketoglutarate salt

BACKGROUND

Ornithine alpha-ketoglutarate salt efficiently improves the nutritional status of protein-depleted patients. Our aim was to explore the effects of ornithine alpha-ketoglutarate supplementation on intestinal physiology in healthy animals.

METHODS

Rats were given a nutritive mixture supplemented with ornithine alpha-ketoglutarate (1 g.kg-1 per day) by enteral route for 7 days. Controls received the diet supplemented with casein acid hydrolysate under isoenergetic and isonitrogenous conditions.

RESULTS

An adaptive hyperplasia of the villi and an increase in the brush-border hydrolase activities were observed in rats receiving ornithine alpha-ketoglutarate. Because of the high ornithine aminotransferase activity, ornithine alpha-ketoglutarate-derived ornithine was extensively transaminated with a concomitant enhancement of ornithine decarboxylation. Surprisingly, with glutamate and putrescine, the products of ornithine transamination and decarboxylation, gamma-aminobutyric acid accumulated (10-fold to 16-fold) dramatically in the intestinal mucosa of rats treated with ornithine alpha-ketoglutarate. Because gamma-aminobutyric acid formation was completely prevented by the diamine oxidase inhibitor aminoguanidine but was not modified after inactivation of ornithine aminotransferase by 5-fluoromethylornithine, it is evident that gamma-aminobutyric acid is formed in the mucosa from ornithine via putrescine as an intermediate.

CONCLUSIONS

It is assumed that enhanced gamma-aminobutyric acid formation in the intestinal mucosa by ornithine alpha-ketoglutarate treatment might be of physiologic importance in the regulatory processes of cell growth and differentiation.

Beneficial effects of L-arginine on intestinal epithelial restitution after ischemic damage in rats

The polyamines are involved in repair processes after intestinal ischemia. Arginine and ornithine, both precursors of polyamines were therefore expected to exert beneficial effects on mucosal barrier dysfunction. Arginine may also generate NO and there is support for the view that NO may be beneficial after an ischemic insult. Male Wistar rats were given, by gavage, isonitrogenous solutions of L-arginine (0.5 g/kg) or L-ornithine (0.7 g/kg) 17 and 2 h before ischemia. Controls received an isonitrogenous solution of casein hydrolysate (1 g/kg). Transient intestinal ischemia was produced in anesthetized rats by occluding the superior mesenteric artery for 90 min. Intestinal morphology, hydrolase activities, polyamine and cGMP contents, and cell proliferation rates were determined 4 h after reperfusion. Administration of arginine or ornithine did not prevent ischemic damage but accelerated morphological repair, enhanced cell proliferation, and polyamine content was observed. Arginine was significantly more effective than ornithine. Formation of cGMP was enhanced after arginine administration. NG-nitroarginine methylester, an inhibitor of NO synthase, prevented the arginine effects on mucosal repair. We conclude that arginine-derived NO is an important mediator in the restitution of intestinal mucosa by minimizing cell injury during reperfusion.

Polyamines and the recovery of intestinal morphology and function after ischemic damage in rats

We have followed the time-course of the morphological and functional recovery of intestinal mucosa after 90 min of mesenteric vascular occlusion. At the end of the ischemic period the villi were smashed, but crypts were preserved. Microvillous hydrolase activities showed a dramatic drop when compared with sham-operated controls. Reperfusion was followed by an immediate upsurge of ornithine decarboxylase activity and a significant (p < 0.01) enhancement of putrescine and N1-acetyl-spermidine concentrations, while spermidine and spermine concentrations in mucosal cells decreased. This indicated that, both, de novo synthesis and degradation rates of the polyamines were increased. Treatment with alpha-difluoromethyl-ornithine, a selective inactivator of ornithine decarboxylase prevented the accumulation of active enzyme, but did not prevent morphological healing. It delayed however the recovery of sucrase and aminopeptidase-specific activities. Our results suggest that in addition to de novo synthesis, other sources of polyamines are mobilized to an extent that growth at a normal rate is supported. This indicates that the presence of active ornithine decarboxylase enzyme is not a prerequisite for the restitution of intestinal integrity after ischemia. We suggest that in a situation of inadequate polyamine supply the restoration of vital processes (mucosal regeneration) has priority over the restoration of specific functions.

Soybean oil, blackcurrant seed oil, medium-chain triglycerides, and plasma phospholipid fatty acids of stressed patients

Thirty-six adult severe head injury and cerebral stroke patients in four intensive-care units were randomized to receive one of three enteral diets for 21 days. These diets, which supplied 45% of calories from fat, differed only in lipid composition. Diet A was comprised of 100% soybean oil, diet B contained a 50:50 (wt/wt) mixture of soybean oil and medium-chain triglycerides (MCTs), and diet C contained 42.5% MCT, 50% soybean oil, and 7.5% blackcurrant seed oils. Plasma phosphatidylcholine and fatty acid composition of plasma total phospholipids were determined before initiating treatment (day 0) and weekly throughout the study. Results indicated that at the start of the study, all patients had low linoleic acid (18:2 omega 6) levels compared with healthy subjects. Emulsion A disturbed the balance between several fatty acids of the omega 6 series, as exemplified by the significant increase in 18:2 omega 6 proportions. In contrast, both emulsions B and C introduced a less-pronounced rise in 18:2 omega 6 associated for emulsion C with a significant increase in dihomo-gamma-linolenic acid (20:3 omega 6) and docosapentaenoic acid (22:5 omega 3) in plasma phospholipids. Furthermore, 18:3 omega 6 change was significantly different between groups A and C and that of 20:3 omega 6 between group A and both groups B and C. Throughout the study, arachidonic acid (20:4 omega 6) exhibited remarkable steady-state levels regardless of the diet. This study shows that providing the injured body with high amounts of 18:2 omega 6 does not lead to high levels of its upper derivatives in plasma phospholipids.(ABSTRACT TRUNCATED AT 250 WORDS)