Fish oil after abdominal aorta aneurysm surgery.

OBJECTIVE: Fish oil (FO) may attenuate the inflammatory response after major surgery such as abdominal aortic aneurysm (AAA) surgery. We aimed at evaluating the clinical impact and safety aspects of a FO containing parenteral nutrition (PN) after AAA surgery. METHODS: Intervention consisted in 4 days of either standard (STD: Lipofundin medium-chain triglyceride (MCT): long-chain triglyceride (LCT)50%-MCT50%) or FO containing PN (FO: Lipoplus: LCT40%-MCT50%-FO10%). Energy target were set at 1.3 times the preoperative resting energy expenditure by indirect calorimetry. Blood sampling on days 0, 2, 3 and 4. Glucose turnover by the (2)H(2)-glucose method. Muscle microdialysis. CLINICAL DATA: maximal daily T degrees, intensive care unit (ICU) and hospital stay. RESULTS: Both solutions were clinically well tolerated, without any differences in laboratory safety parameters, inflammatory, metabolic data, or in organ failures. Plasma tocopherol increased similarly; with FO, docosahexaenoic and eicosapentaenoic acid increased significantly by day 4 versus baseline or STD. To increased postoperatively, with a trend to lower values in FO group (P=0.09). After FO, a trend toward shorter ICU stay (1.6+/-0.4 versus 2.3+/-0.4), and hospital stay (9.9+/-2.4 versus 11.3+/-2.7 days: P=0.19) was observed. CONCLUSIONS: Both lipid emulsions were well tolerated. FO-PN enhanced the plasma n-3 polyunsaturated fatty acid content, and was associated with trends to lower body temperature and shorter length of stay.

Safety and intestinal tolerance of high-dose enteral antioxidants and glutamine peptides after upper gastrointestinal surgery.

OBJECTIVE: Safety and intestinal tolerance of an early high-dose enteral administration of antioxidative vitamins, trace elements, and glutamine dipeptides. DESIGN: open intervention trial. SETTING: Two university teaching hospitals. PATIENTS: A total of 14 patients requiring jejunal feeding (64+/-14 y). INTERVENTION: A measure of 500 ml/day Intestamin (FreseniusKabi: 250 kcal/1.050 kJ, 300 microg selenium, 20 mg zinc, 400 mug chromium, 1500 mg vitamin C, 500 mg vitamin E, 10 mg beta-carotene, 30 g glutamine) for 5 days beginning 6 h after surgery. Parenteral/enteral nutrition was provided to achieve energy target (25 kcal/kg/day). ASSESSMENTS: Intestinal complaints, plasma nutrients, and glutathione. RESULTS: Only minor signs of nausea, hiccups, flatulence (3/14). Plasma micronutrients (except beta-carotene) postoperatively decreased and increased to normal on day 5. Extracellular glutamine remained low (preop: 520+/-94; d1: 357+/-67; d5: 389+/-79 micromol/l); total glutathione decreased (d1: 9.4+/-3.8; d5: 3.6+/-2.5 micromol/l). CONCLUSION: Study feed is well tolerated and metabolically safe representing a valuable tool for targeted pharmaconutrient supply.

Exudative mineral losses after serious burns: a clue to the alterations of magnesium and phosphate metabolism.

Hypomagnesemia and hypophosphatemia are frequent after severe burns; however, increased urinary excretion does not sufficiently explain the magnitude of the mineral depletion. We measured the mineral content of cutaneous exudates during the first week after injury. Sixteen patients aged 34 +/- 9 y (mean +/- SD) with thermal burns were studied prospectively and divided in 3 groups according to the extent of their burn injury and the presence or absence of mineral supplements: group 1 (n = 5), burns covering 26 +/- 5% of body surface; group 2 (n = 6), burns covering 41 +/- 10%; and group 3 (n = 5), burns covering 42 +/- 6% with prescription of magnesium and phosphate supplements. Cutaneous exudates were extracted from the textiles (surgical drapes, dressings, sheets, etc) surrounding the patients from day 1 to day 7 after injury. Mean magnesium serum concentrations decreased below reference ranges in 12 patients between days 1 and 4 and normalized thereafter. Phosphate, normal on day 0, was low during the first week. Albumin concentrations, normal on day 0, decreased and remained low. Urinary magnesium and phosphate excretion were within reference ranges and not larger in group 3. Mean daily cutaneous losses were 16 mmol Mg/d and 11 mmol P/d (largest in group 2). Exudative magnesium losses were correlated with burn severity (r = 0.709, P = 0.003). Cutaneous magnesium losses were nearly four times larger than urinary losses whereas cutaneous phosphate losses were smaller than urinary phosphate losses. Mean daily losses of both magnesium and phosphate were more than the recommended dietary allowances. Exudative losses combined with urinary losses largely explained the increased mineral requirements after burn injury.

Trace element supplementation modulates pulmonary infection rates after major burns: a double-blind, placebo-controlled trial.

Infections remain the leading cause of death after major burns. Trace elements are involved in immunity and burn patients suffer acute trace element depletion after injury. In a previous nonrandomized study, trace element supplementation was associated with increased leukocyte counts and shortened hospital stays. This randomized, placebo-controlled trial studied clinical and immune effects of trace element supplements. Twenty patients, aged 40 +/- 16 y (mean +/- SD), burned on 48 +/- 17% of their body surfaces, were studied for 30 d after injury. They consumed either standard trace element intakes plus supplements (40.4 micromol Cu, 2.9 micromol Se, and 406 micromol Zn; group TE) or standard trace element intakes plus placebo (20 micromol Cu, 0.4 micromol Se, and 100 micromol Zn; group C) for 8 d. Demographic data were similar for both groups. Mean plasma copper and zinc concentrations were below normal until days 20 and 15, respectively (NS). Plasma selenium remained normal for group TE but decreased for group C (P < 0.05 on days 1 and 5). Total leukocyte counts tended to be higher in group TE because of higher neutrophil counts. Proliferation to mitogens was depressed compared with healthy control subjects (NS). The number of infections per patient was significantly (P < 0.05) lower in group TE (1.9 +/- 0.9) than in group C (3.1 +/- 1.1) because of fewer pulmonary infections. Early trace element supplementation appears beneficial after major burns; it was associated with a significant decrease in the number of bronchopneumonia infections and with a shorter hospital stay when data were normalized for burn size.

The effects of midazolam reversal by RO 15-1788 on cerebral perfusion pressure in patients with severe head injury.

In patients with severe head injury, midazolam is a convenient agent for sedation during mechanical ventilation, although its sedative effect can be prolonged. We investigated the effects of acute midazolam reversal by RO 15-1788 (RO), a benzodiazepine antagonist, on intracranial pressure (ICP), cerebral perfusion pressure (CPP) and on recovery in 18 studies performed on 15 patients with severe head injury (Glasgow coma score less than 8). ICP increased significantly from 16.3 mmHg +/- 2 (mean +/- SEM) to 24.1 mmHg +/- 4.2 (p less than 0.02) and to 25.2 mmHg +/- 4 (p less than 0.01), 5 and 10 min respectively after RO administration. Analysis of the results showed 2 patterns of response in ICP. In patients with good control of ICP before RO administration, there was no change in ICP and CPP, whereas in patients with abnormal ICP, RO injection induced severe increase in ICP and concomitant decrease in CPP. Arousal after midazolam reversal was obvious in 5 patients who were quickly extubated. Midazolam reversal by RO should not be attempted in patients with severe head injury and unstable ICP.

Assessment of changes in body water by bioimpedance in acutely ill surgical patients.

OBJECTIVE: To evaluate the relationship between changes in body bioelectrical impedance (BI) at 0.5, 50 and kHz and the changes in body weight, as an index of total body water changes, in acutely ill surgical patients during the rapid infusion of isotonic saline solution. DESIGN: Prospective clinical study. SETTING: Multidisciplinary surgical ICU in a university hospital. PATIENTS: Twelve male patients treated for acute surgical illness (multiple trauma n = 5, major surgery n = 7). SELECTION CRITERIA: stable cardiovascular parameters, normal cardiac function, signs of hypovolemia (CVP < or = 5 mmHg, urine output < 1 ml/kg x h). INTERVENTIONS: After baseline measurements, a 60 min fluid challenge test was performed with normal saline solution, 0.25 ml/kg/min [corrected]. MEASUREMENTS AND RESULTS: Body weight (platform digital scale), total body impedance (four-surface electrode technique; measurements at 0.5, 50 and 100 kHz) and urine output. Fluid retention induced a progressive decrease in BI at 0.5, 50 and 100 kHz, but the changes were significant for BI 0.5 and BI 100 only, from 40 min after the beginning of the fluid therapy onwards. There was a significant negative correlation between changes in water retention and BI 0.5, with individual correlation coefficients ranging from -0.72 to 0.95 (p < 0.01-0.0001). The slopes of the regression lines indicated that for each kg of water change, there was a mean decrease in BI of 18 ohm, but a substantial inter-individual variability was noted. CONCLUSION: BI measured at low frequency can represent a valuable index of acute changes in body water in a group of surgical patients but not in a given individual.

Impact of a bicarbonated saline solution on early resuscitation after major burns.

OBJECTIVE: The study aimed at assessing the impact of the introduction of a bicarbonated saline solution on total fluid load, weight gain and acid base status during acute burn resuscitation. DESIGN: Based on a retrospective patient record review. SETTING: Burn care centre of a surgical ICU in a tertiary university hospital. PATIENTS: Two groups of adult patients (20/20), with thermal burns of 25% or more body surface area were studied. INTERVENTION: Modification of the resuscitation fluid composition from lactated Ringer's solution (LR: Na 132 mmol/l, Cl 112 mmol/l, 263 mosm/l), to bicarbonated 0.9% saline (BS: Na 180 mmol/l, Cl 154 mmol/l, 340 mosm/l) METHODS: Age, weight, burn size and depth, inhalation injury, fluid intakes over 48 h post-injury, plasma sodium, chloride, creatinine, albumin levels, blood gases and ventilation support were recorded. RESULTS: The demographic characteristics of the patients (41 +/- 16 years) in the two groups were not different, with severe burns involving 44 +/- 17% body surface area. While the total fluid volumes administered did not differ, BS was associated with lower plasma pH, base excess and bicarbonate levels for 24 h and with hyperchloraemia. Clinical evolution did not differ. CONCLUSIONS: Using bicarbonated saline solution for resuscitation causes a transient hyperchloraemic dilutional acidosis compared with LR, and has no other detectable clinical impact over the first 10 days after severe burn injury.

Influence of selenium supplements on the post-traumatic alterations of the thyroid axis: a placebo-controlled trial.

OBJECTIVE: To investigate whether early selenium (Se) supplementation can modify the post-traumatic alterations of thyroid hormone metabolism, since the first week after trauma is characterised by low plasma Se and negative Se balances. DESIGN: Prospective, placebo-controlled randomised supplementation trial. SETTING: Surgical ICU in a tertiary university hospital. PATIENTS: Thirty-one critically ill trauma patients aged 42 +/- 16 years (mean +/- SD), with severe multiple injury (Injury Severity Score 30 +/- 7). INTERVENTION: Supplementation during the first 5 days after injury with either Se or placebo. The selenium group was further randomised to receive daily 500 microg Se, with or without 150 mg alpha-tocopherol (AT) and 13 mg zinc supplements. The placebo group received the vehicle. Circulating Se, AT, zinc, and thyroid hormones were determined on D0 (= day 0, admission), D1, D2, D5, D10, and D20. RESULTS: Plasma Se, low on D0, normalised from D1 in the selenium group; total T4 and T3 increased more and faster after D2 (P = 0.04 and 0.08), reverse T3 rising less between D0 and D2 (P = 0.05). CONCLUSIONS: Selenium supplements increased the circulating Se levels. Supplementation was associated with modest changes in thyroid hormones, with an earlier normalisation of T4 and reverse T3 plasma levels. The addition of AT and zinc did not produce any additional change.

Segmental body composition assessed by bioelectrical impedance analysis and DEXA in humans.

The present study assessed the relative contribution of each body segment to whole body fat-free mass (FFM) and impedance and explored the use of segmental bioelectrical impedance analysis to estimate segmental tissue composition. Multiple frequencies of whole body and segmental impedances were measured in 51 normal and overweight women. Segmental tissue composition was independently assessed by dual-energy X-ray absorptiometry. The sum of the segmental impedance values corresponded to the whole body value (100.5 +/- 1.9% at 50 kHz). The arms and legs contributed to 47.6 and 43.0%, respectively, of whole body impedance at 50 kHz, whereas they represented only 10.6 and 34.8% of total FFM, as determined by dual-energy X-ray absorptiometry. The trunk averaged 10.0% of total impedance but represented 48.2% of FFM. For each segment, there was an excellent correlation between the specific impedance index (length2/impedance) and FFM (r = 0.55, 0.62, and 0.64 for arm, trunk, and leg, respectively). The specific resistivity was in a similar range for the limbs (159 +/- 23 cm for the arm and 193 +/- 39 cm for the leg at 50 kHz) but was higher for the trunk (457 +/- 71 cm). This study shows the potential interest of segmental body composition by bioelectrical impedance analysis and provides specific segmental body composition equations for use in normal and overweight women.

A 10-year survey of nutritional support in a surgical ICU: 1986-1995.

Total parenteral nutrition (TPN) has long been considered the optimal nutrition technique in critically ill patients, but recently the use of enteral nutrition (EN) has increased. This study describes the evolution of the different nutritional support techniques in a surgical intensive care unit (ICU) in a university hospital, through (1) a global survey over 10 y assessing the evolution of the use of EN and TPN, and (2) a prospective study performed over 6 mo. Severity of illness and diagnostic categories were stable (n = 11,539 patients). From 1986 to 1990, the proportion of TPN administered increased from 10-25% of ICU days, decreasing to 10% thereafter. EN was used in about 5% of ICU days in 1986, and had increased to 30% of total ICU treatment days in 1995. The proportion of nutrients actually delivered to the patients was 75% with EN and 88% with TPN. Major changes in nutritional support have been observed since 1986. The frequency of nutritional support provided in general has increased to 40% of ICU treatment days. TPN has been largely overtaken by EN, with the risk of insufficient energy delivery, related to the difficulties of EN in the critically ill. These results reinforce the importance of continuous quality control by daily assessment of nutrient supply.

Effects of beta-blockade on energy metabolism following burns.

The purpose of this study was to compare the effects of propranolol administered either by i.v. infusion or by prolonged oral administration (4 days) during the first 3 weeks following burns. The resting metabolic rate (RMR) of 10 non-infected fasting burned patients (TBSA: 28 per cent, range 18-37 per cent) was determined four times consecutively by indirect calorimetry (open circuit hood system) following: (1) i.v. physiological saline; (2) i.v. propranolol infusion (2 micrograms/kg/min following a bolus of 80 micrograms/kg); (3) oral propranolol (40 mg q.i.d. during 4 +/- 1 days); and (4) in control patients. All patients showed large increases in both RMR (144 +/- 2 per cent of reference values) and in urinary catecholamine excretion (three to four times as compared to control values). The infusion of propranolol induced a significant decrease in RMR to 135 +/- 2 per cent and oral propranolol to 129 +/- 3 per cent of reference values. A decrease in lipid oxidation but no change in carbohydrate and protein oxidation were observed during propranolol administration. It is concluded that the decrease in RMR induced by propranolol was not influenced by the route of administration. The magnitude of the decrease in energy expenditure suggests that beta-adrenergic hyperactivity represents only one of the mediators of the hypermetabolic response to burn injury.

[Sedation interruption in neurointensive care]. / Arrêt de la sédation en neuroréanimation.

The reasons for sedation in neurointensive care can be divided into two main groups: (i) general indications, as for other intensive care patients, such as to allow the necessary treatments (therapeutic facilitation), controlling the states of agitations em leader; (ii) specific indications due to the neuro-physiologic effect of the sedatives: facilitation of the control of the intracranial pressure and lowering of the cortical excitability during the epileptic fits and thereby helping the recovery of the cerebral tissue and diminishing the secondary brain insults. It is important to remember that sedation is usually combined with the administration of opioids, which can potentiate the effect of the sedative drugs. The interruption of the sedation can be long- or short-termed. The definitive interruption is possible once the clinical and cerebral state of the patient does not justify any sedation, whereas the brief interruption allows a neurological reassessment. The amount of literature on sedation in intensive care is opposed to the few studies on neurointensive care: in January 2003, the American Society of Intensive Care has published recommendations for this topic without mentioning the interruption of sedation in neurointensive care patients. The aim of this article is to review the literature about the effects of the interruption of the sedation in neurointensive care patients.

[Use of flumazenil (RO 15-1788) after prolonged infusion of midazolam in anesthesia for intracranial surgery]. / Utilisation du flumazénil (Ro 15-1788) après perfusion prolongée de midazolam en anesthésie pour chirurgie intracrânienne.

Midazolam, with a half-life of about 1.5-3.5 h, is inappropriate for the maintenance of anaesthesia during long procedures, especially when rapid recovery is necessary. The efficacy of flumazenil, a specific benzodiazepine antagonist, in the treatment of patients with benzodiazepine overdose suggests that rapid recovery from anaesthesia induced and maintained with midazolam might be obtained in patients needing immediate assessment. The rate of recovery, the side-effects and the feasibility of an early and accurate neurological assessment were studied in 18 ASA III patients after craniotomy in whom the prolonged effects of midazolam had been antagonized by flumazenil. Surgery lasted 5.5 +/- 1.3 h (means +/- SD). The induction dose of midazolam was 0.32 +/- 0.08 mg.kg-1 and the infusion rate was 0.2 +/- 0.08 mg.kg-1.h-1. Fentanyl was added at a dose and rate of 5.0 +/- 3.6 micrograms.kg-1 and 2.0 +/- 0.9 micrograms.kg-1.h-1 respectively. At the end of the dressing, 0.5 mg of flumazenil (t0) was injected, followed by 0.1 mg every minute up to a total of 1 mg. After 2 min, 14 patients (78%) opened their eyes (p less than 0.05) and 13 (72%) obeyed orders (p less than 0.05). After 10 min, 16 patients (89%) were extubated and speaking. During the first 10 min, the Glasgow score and the sedation score used for this study showed the same progression, with 13 patients (72%) having a Glasgow score of 14-15 (p less than 0.05). Thereafter, both scores decreased progressively till t60, then increased again, reaching their t10 level at t120. Three patients required another dose of antagonist.(ABSTRACT TRUNCATED AT 250 WORDS)

[Energy metabolism and craniocerebral injury]. / Métabolisme énergétique et traumatisme crâniocérébral.

Severe head injury induces major hormonal, humoral and metabolic changes, characterized by increases in stress hormone secretion, lymphokines production, associated with high lipid and protein catabolism as well as changes in energy expenditure (EE). Numerous factors influence EE in head-injured patients, particularly anthropometric data, body temperature, nutritional support, level of consciousness, muscular tone and activity. Resting EE is usually increased following brain trauma; however, normal or decreased metabolic rates can be observed in curarized patients on mechanical ventilation or in patients receiving high doses of barbiturates.

[Principles of the use of indirect calorimetry in intensive care]. / Principes d'utilisation de la calorimétrie indirecte en médecine intensive.

Energy expenditure measurements in critically ill patients using indirect calorimetry is complex and often very inaccurate. Analysis of the data should first question their validity. The components of energy expenditure should be carefully separated to assess the effects of illness, drugs and supportive treatments.

Anaesthesia for procedures in the intensive care unit.

Taking in charge severely ill patients in the intensive care environment to manage complex procedures is a performance requiring highly specific knowledge. Close collaboration between anaesthetists and intensive care specialists is likely to improve the safety and quality of medical care. Three forms of anaesthetic care should be considered in clinical practice: sedation and analgesia; monitored anaesthetic care; and general anaesthesia or conduction block anaesthesia. Even in the field of sedation and analgesia, the anaesthesiologist can offer expertise on new anaesthetic techniques like: the most recent concepts of balanced anaesthesia in terms of pharmacokinetics and dynamics, favouring the use of short-acting agents and of sedative-opioid combinations. New modes of administration and monitoring intravenous anaesthesia have been developed, with potential application in the intensive care unit. These include the use of target-controlled administration of intravenous drugs, and of electroencephalographic signals to monitor the level of sedation.

Sedatives and antagonists in the management of severely head-injured patients.

Continuous intravenous sedation is often prescribed during the intensive treatment of severe head injury. It is known that intravenous hypnotics may prevent or treat the brief intracranial hypertension episodes associated with nociceptive stimuli, like tracheal intubation. However there is yet no clear evidence in the literature showing beneficial effects of sedation in severely head-injured patients on intracranial pressure control or outcome. Sedation should be primarily administered in neurotraumatology to allow good conditions for intensive treatment, while avoiding any depressive cardiovascular action. The abrupt reversal of sedation by means of specific antagonists may induce significant elevation of both cerebral blood flow and intracranial pressure and should be avoided.