Association of hyperglycemia with increased mortality after severe burn injury.

BACKGROUND: Hyperglycemia is commonly associated with the hypermetabolic stress response. However, persistent hyperglycemia may adversely affect wound healing and immunity. The purpose of this study was to assess any relationship between hyperglycemia and clinical outcome after severe burn injury. METHODS: Survey of the medical records from January 1996 to July 1999 identified 58 pediatric patients with burns > or = 60% body surface. Patients were categorized as having poor glucose control (n = 33) if > or = 40% of all plasma glucose determinations were > or = 7.8 mmol/L (140 mg/dL) and compared with patients deemed to have adequate glucose control (n = 25) in whom > or = 40% of all glucose values were > or = 7.8 mmol/L. RESULTS: Despite similar age, burn size, caloric intake, and frequency of wound infection, patients categorized with poor glucose control had a significantly greater incidence of positive blood cultures (positive blood cultures/length of stay days, 0.42 +/- 0.04 for hyperglycemia patients vs. 0.30 +/- 0.03 for normoglycemia patients; mean +/- SEM, p > or = 0.05). This finding was especially prominent for blood cultures positive for yeast. Hyperglycemia patients had significantly less percentage of skin graft take than did the normoglycemic patients (percent take/operative procedure, 64 +/- 9 for hyperglycemia patients vs. 88 +/- 5 for normoglycemia patients; p < 0.05). Nine patients (27%) with persistent hyperglycemia died compared with only one death (4%) in patients with adequate glucose control (p > or = 0.05). CONCLUSION: This association between poor glucose control, bacteremia/fungemia, reduced skin graft take, and subsequent mortality in severely burned children may be related to a hyperglycemia-induced detriment in antimicrobial defense. Although this report fails to establish cause and effect, these findings suggest that aggressive maneuvers to normalize plasma glucose in critically injured patients may be warranted.

Measurement of hemoglobin synthesis rate in vivo using a stable isotope method.

We developed a method to measure hemoglobin synthesis rate (SynHb) in humans, assuming that free glycine in the red blood cell (RBC) represents free glycine in bone marrow for hemoglobin synthesis. The present rat study examines this assumption of the method and quantifies SynHb in rats. Sprague-Dawley rats (n = 9) were studied, [2-(13)C]glycine was intravenously infused over 24 h (2.5 mg kg(-1) h(-1)), blood was drawn for glycine and heme isolation, and bone marrow was harvested for glycine isolation. Isotopic enrichments of glycine and heme were measured, fractional hemoglobin synthesis rate (fSynHb% day(-1)) was calculated, and from this a value for SynHb (mg g(-1) day(-1)) was derived. Mean body weight was 446 +/- 10 g (mean +/- SE) and hemoglobin concentration was 14 +/- 0.5 g dl(-1). At 24 h, the mean isotopic enrichment, atom percentage excess (APE), of the RBC free glycine (1.56 +/- 0.18 APE) was similar to the bone marrow (1.68 +/- 0.15 APE). The rate of incorporation of (13)C into heme increased over time from 0.0004 APE/h between 6 and 12 h, to 0.0014 APE/h between 12 and 18 h, and 0.0024 APE/h between 18 and 24 h. Consequently, fSynHb (1.19 +/- 0.32, 2.92 +/- 0.66, and 4.22 +/- 0.56% day(-1), respectively) and SynHb (0.11 +/- 0.03, 0.28 +/- 0.05, and 0.42 +/- 0.05 mg g(-1) day(-1), respectively) showed similar patterns over the 24-h study period. We conclude that (1) enrichment of free glycine in the circulating RBC approximates enrichment of bone marrow free glycine for heme formation and (2) this pattern of hemoglobin synthesis rate is reflecting the characteristic release and gradual maturation of reticulocytes in the circulation.

Influence of glucose kinetics on plasma lactate concentration and energy expenditure in severely burned patients.

BACKGROUND: In critically ill patients, elevation in the plasma lactate concentration has traditionally been interpreted as indicating a deficiency in oxygen availability and is often an impetus to increase oxygen delivery clinically. However, another possible basis for increased lactate concentrations may be simply a mass effect from increased pyruvate availability (i.e., accelerated glycolysis). METHODS: In six hypermetabolic burned patients, the rates of glucose production and oxidation were quantified using a tracer infusion of 6,6 d2 glucose combined with indirect calorimetry. Measurements were obtained after a 9-hour fast and after a 3-hour infusion of unlabeled glucose at 30 micromol/kg/min. No patient was overtly septic, hypoxic, or hypovolemic. RESULTS: The infusion of glucose significantly increased the arterial glucose concentration and rate of glucose oxidation, with a corresponding increase in the arterial plasma concentration of lactate and pyruvate. Resting energy expenditure and oxygen consumption were not affected by the infusion of glucose. CONCLUSIONS: These findings show that elevations in plasma lactate in severely injured patients may, in part, be related to increases in glucose flux and not entirely a reflection of any deficit in oxygen availability. Such findings highlight a potential pitfall for interpreting plasma lactate concentrations as an index of tissue oxygen availability in hypermetabolic patients.

Determinants of skeletal muscle catabolism after severe burn.

OBJECTIVE: To determine which patient factors affect the degree of catabolism after severe burn. SUMMARY BACKGROUND DATA: Catabolism is associated with severe burn and leads to erosion of lean mass, impaired wound healing, and delayed rehabilitation. METHODS: From 1996 to 1999, 151 stable-isotope protein kinetic studies were performed in 102 pediatric and 21 adult subjects burned over 20-99. 5% of their total body surface area (TBSA). Patient demographics, burn characteristics, and hospital course variables were correlated with the net balance of skeletal muscle protein synthesis and breakdown across the leg. Data were analyzed sequentially and cumulatively through univariate and cross-sectional multiple regression. RESULTS: Increasing age, weight, and delay in definitive surgical treatment predict increased catabolism (P < .05). Body surface area burned increased catabolism until 40% TBSA was reached; catabolism did not consistently increase thereafter. Resting energy expenditure and sepsis were also strong predictors of net protein catabolism. Among factors that did not significantly correlate were burn type, pneumonia, wound contamination, and time after burn. From these results, the authors also infer that gross muscle mass correlates independently with protein wasting after burn. CONCLUSIONS: Heavier, more muscular subjects, and subjects whose definitive surgical treatment is delayed are at the greatest risk for excess catabolism after burn. Sepsis and excessive hypermetabolism are also associated with protein catabolism.

Both dermal matrix and epidermis contribute to an inhibition of wound contraction.

Contracture is a major detriment to functional recovery from large wounds. To determine the relative value of dermal replacement and epidermal coverage in inhibiting wound contraction, five full-thickness wounds (all 5 x 5 cm2) were placed on the back of 8 swine and treated in the following manner: (1) open wound, (2) porcine acellular dermis (analogous to AlloDerm for human use), (3) porcine acellular dermis with epidermal autograft placed 7 days postwounding, (4) porcine acellular dermis with immediate epidermal autograft, and (5) conventional-thickness autograft. Scar dimensions and punch biopsies were taken at days 14 and 30 postwounding. The planimetry results demonstrated that wound contraction was significantly greater with the open wounds (group 1) than all other wounds with a dermal substitute. Furthermore, wounds with initial epidermal coverage had significantly less contraction than unepithelialized wounds (14.8 +/- 1.1 cm2 at day 14 in wound group 2 vs. 20.4 +/- 0.6 cm2 in wound group 4; p < 0.05). Biopsy results revealed that wounds with initial epithelial coverage had the least amount of inflammation. These findings suggest that both dermal matrix and epidermal coverage contribute to an inhibition of wound contraction and that prompt epithelial coverage appears to impede contraction by reducing inflammation.

Gut gavage with antiendotoxin antibodies reduces the liberation of tumor necrosis factor-alpha after hemorrhage/resuscitation.

OBJECTIVE: To evaluate the effect of gut gavage both alone and with enteral administration of monoclonal antibodies to endotoxin on the liberation of tumor necrosis factor (TNF)-alpha and subsequent hemodynamics after hemorrhage/resuscitation. DESIGN: Dose response intervention, sham-controlled animal study. SETTING: Research laboratory at a university medical center. ANIMALS: Instrumented rats (250-325 g body weight) underwent standardized hemorrhage/resuscitation. INTERVENTIONS: Animal groups received 4 hrs before hemorrhage/resuscitation: gastric gavage with Colyte alone (group 1), combined with E5 antiendotoxin at either 0.2 mg/100 g (group 2) or 2 mg/100 g body weight (group 3), or sham controls (group 4). There were six animals studied in each of the four groups. MEASUREMENTS AND MAIN RESULTS: For animals receiving gut gavage and high-dose E5 antiendotoxin, plasma concentrations of TNF-alpha (pg/mL) at 120 mins after hemorrhage/resuscitation were significantly lower compared with sham controls (16+/-4 group 3; 65+/-36 group 4; mean +/- SD, p < .05). At 300 mins, this same treatment group had a significantly higher mean blood pressure (mm Hg) (110+/-6 group 3; 86+/-7 group 4: p < .05). Also at 300 mins after hemorrhage/resuscitation, plasma lactate concentrations (mmol/L) were significantly lower for all gut gavage treatment groups compared with sham control animals (1.9+/-0.2 group 1; 2.0+/-0.2 group 2; 1.8+/-0.2 group 3; 4.8+/-2.8 group 4, p < .05). CONCLUSIONS: Prior treatment with gut gavage and enterally administered antiendotoxin antibodies reduces TNF-alpha liberation after hemorrhage/resuscitation and confers a subsequent improvement in hemodynamics and decreased plasma lactate concentrations. Such therapy may be efficacious in patients undergoing elective procedures where major hemorrhage is likely or in severely injured patients with continued or recurrent hemorrhage.

Complementary roles of laparoscopic abdominal exploration and diagnostic peritoneal lavage for evaluating abdominal stab wounds: a prospective study.

PURPOSE: To determine the roles of laparoscopic abdominal exploration (LE) and diagnostic peritoneal lavage (DPL) in the evaluation of abdominal stab wounds, we prospectively compared LE with mandatory celiotomy (MC) in 76 patients having anterior abdominal stab wounds penetrating the fascia over a 22-month period. PATIENTS AND METHODS: Twenty-two patients underwent emergency celiotomy. The remaining patients were subjected to DPL and assigned to treatment by either celiotomy or initial LE with subsequent conversion to open exploration at the discretion of the attending surgeon. RESULTS: Laparotomy was avoided in 55% of the 31 patients undergoing initial laparoscopy, and this group demonstrated a significant decrease in the incidence of nontherapeutic celiotomy, from 19% to 57% (P < 0.05), as well as decreased length of hospital stay (4 +/- 0.6 v 5.9 +/- 0.4 days; P < 0.05), and total hospital cost ($6119 +/- 756 v $8312 +/- 627; P < 0.05). There were no missed intraabdominal injuries or morbidity from laparoscopy identified in follow-up. The DPL (N = 36) was positive in 11 of the 12 patients with injury requiring surgical repair and was negative in 16 of the 25 patients not requiring repair. The sensitivity and specificity of DPL were 0.91 and 0.64 compared with 1.0 and 0.74 for laparoscopy. CONCLUSIONS: An algorithm to evaluate stable patients with anterior abdominal stab wounds and minimize overall costs of care, incidence of nontherapeutic celiotomy, and rate of missed injuries is suggested consisting of DPL followed by observation in patients with negative DPL and by laparoscopy in patients with positive DPL. Wounds to the thoracoabdominal region may be best evaluated by initial LE, as diaphragmatic wounds may result in a false-negative DPL.

Combined effects of hyperaminoacidemia and oxandrolone on skeletal muscle protein synthesis.

We investigated whether the normal anabolic effects of acute hyperaminoacidemia were maintained after 5 days of oxandrolone (Oxandrin, Ox)-induced anabolism. Five healthy men [22 +/- 3 (SD) yr] were studied before and after 5 days of oral Ox (15 mg/day). In each study, a 5-h basal period was followed by a 3-h primed-continuous infusion of a commercial amino acid mixture (10% Travasol). Stable isotopic data from blood and muscle sampling were analyzed using a three-compartment model to calculate muscle protein synthesis and breakdown. Model-derived muscle protein synthesis increased after amino acid infusion in both the control [basal control (BC) vs. control + amino acids (C+AA); P < 0.001] and Ox study [basal Ox (BOx) vs. Ox + amino acids (Ox+AA); P < 0.01], whereas protein breakdown was unchanged. Fractional synthetic rates of muscle protein increased 94% (BC vs. C+AA; P = 0.01) and 53% (BOx vs. Ox+AA; P < 0.01), respectively. We conclude that the normal anabolic effects of acute hyperaminoacidemia are maintained in skeletal muscle undergoing oxandrolone-induced anabolism.

Androstenedione does not stimulate muscle protein anabolism in young healthy men.

Androstenedione is the immediate precursor of testosterone. Androstenedione intake has been speculated to increase plasma testosterone levels and muscle anabolism. Thus, androstenedione supplements have become widely popular in the sport community to improve performance. This study was designed to determine whether 5 days of oral androstenedione (100 mg/day) supplementation increases skeletal muscle anabolism. Six healthy young men were studied before the treatment period and after 5 days of oral androstenedione supplementation. Muscle protein turnover parameters were compared to those of a control group studied twice as well and receiving no treatment. We measured muscle protein kinetics using a three-compartment model involving infusion of L-[ring-2H5]phenylalanine, blood sampling from femoral artery and vein, and muscle biopsies. Plasma testosterone, androstenedione, LH, and estradiol concentrations were determined by RIA. After ingestion of oral androstenedione, plasma testosterone and LH concentrations did not change from basal, whereas plasma androstenedione and estradiol concentrations were significantly increased (P<0.05). Compared to a control group, androstenedione did not affect muscle protein synthesis and breakdown, or phenylalanine net balance across the leg. We conclude that oral androstenedione does not increase plasma testosterone concentrations and has no anabolic effect on muscle protein metabolism in young eugonadal men.

Deficiency in peripheral glutamine production in pediatric patients with burns.

Plasma glutamine levels decrease in association with severe injury, which suggests that the consumption of glutamine exceeds the production of glutamine or possibly represents a deficit in the release of glutamine from skeletal muscle. The goal of this study was to assess the peripheral glutamine kinetic response to prolonged stress in children with critical injuries. To accomplish this purpose, we quantitated peripheral glutamine kinetics in vivo with the use of 5N15 glutamine in 5 children with severe burns (total body surface area, 74%+/-14%; mean +/- SEM) and 3 children who underwent elective scar reconstruction. In the children with severe burns, leg blood flow was significantly elevated (16.2+/-2.1 vs 7.5 +/-0.3 mL/min/100 mL leg volume, P < .02) and the arterial concentration of glutamine was significantly reduced (0.31+/-0.04 vs 0.84+/-0.05 mmol/L, P < .001). The rate of glutamine turnover within the leg was significantly reduced in the patients with acute burns, whereas the net efflux of glutamine was similar between the 2 groups. These findings suggest that plasma glutamine concentrations decrease during severe stress as a result of a deficit in peripheral glutamine release in conjunction with an increased central consumption. This preliminary study supports the notion that exogenous glutamine supplementation in pediatric patients with severe injuries may be needed because of this inadequate skeletal muscle response.

Accelerated glutamine synthesis in critically ill patients cannot maintain normal intramuscular free glutamine concentration.

BACKGROUND: Muscle glutamine is severely depleted in critically ill patients (by approximately 50% to 80% of normal). Because muscle protein breakdown, and thus the release of glutamine from muscle protein, is enhanced in response to metabolic stress, the depletion of intramuscular glutamine could be due to its impaired synthesis or accelerated outward transport or both. METHODS: To distinguish these possibilities, we measured skeletal muscle glutamine metabolism in five critically ill patients by means of primed, continuous infusions of 5-15N-glutamine and ring-2H5-phenylalanine and compared them to values we previously reported for healthy volunteers. RESULTS: The intramuscular free glutamine concentration in patients was approximately 70% of that in healthy volunteers (5.8 +/- 0.6 mmol/L intracellular free water vs 21.5 +/- 2.8 mmol/L). Whole-body glutamine rate of appearance was 5.8 +/- 1.0 micromol x kg (-1) body wt x min (-1), and whole-body clearance was 19.3 +/- 3.3 mL x kg(-1) x min (-1). Despite the low intramuscular glutamine concentration in the patients, the rate of unidirectional outward transport from skeletal muscle into venous blood (1.1. +/- 0.2 micromol x 100 mL x leg(-1) x min(-1)) was similar to that observed in healthy volunteers (1.6 +/- 0.2 mol x 100 mL x leg(-1) x min(-1)); intramuscular synthesis was 2.7 +/- 0.9 micromol x 100 mL x leg(-1) x min(-1) compared with a normal value of 0.6 +/- 0.06 micromol x 100 mL x leg(-1) x min(-1). Net balance across the leg was normal. CONCLUSIONS: The depletion of intramuscular glutamine in critically ill patients is not due to an impairment of the rate of synthesis. In fact, accelerated glutamine production cannot maintain normal intramuscular glutamine levels because of accelerated outward transport.

Bronchoscopic lavage with perfluorocarbon decreases postprocedure hypoxemia in an ovine model of smoke inhalation.

OBJECTIVE: Bronchoscopy and lavage are used to confirm diagnosis and can be therapeutic in patients suffering inhalation injury. Lavage is traditionally performed using saline, which is unfortunately associated with profound transient hypoxemia. Perfluorocarbons, having a high gas solubility for oxygen and carbon dioxide, increase oxygenation when instilled into the airway. We hypothesized that the use of perfluorocarbons for bronchoscopic lavage would attenuate this transient hypoxemia. METHODS: Sheep were prepared for chronic study. They were insufflated with cotton smoke and then randomized to receive a lavage with 200 mL of perfluorocarbon or saline at 2, 6, 12, and 24 hours after injury. RESULTS: All animals had a steady and significant decline in their pre- to post-PaO2/FiO2 (P/F) ratio. At 2, 6, and 12 hours, the saline lavage group had a significant decrease in their P/F ratio (485+/-32 to 212+/-37 mm Hg, 439+/-22 to 170+/-40 mm Hg, and 381+/-48 to 184+/-59 mm Hg). This decrease in P/F ratio was not observed in the perfluorocarbon group (474+/-19 to 459+/-29 mm Hg, 424+/-32 to 387+/-43 mm Hg, and 366+/-50 to 357+/-67 mm Hg). CONCLUSION: These findings indicate that perfluorocarbons attenuate the transient hypoxemia associated with saline bronchoscopic lavage and thus may be considered safer for patients with acute lung injury.

Hemodynamic and ventilatory effects associated with increasing inverse inspiratory-expiratory ventilation.

BACKGROUND: Increasing the percentage of inspiratory time during mechanical ventilation (i.e., inverse inspiratory-expiratory (I:E) ventilation) is frequently used to improve oxygenation in patients with acute respiratory distress syndrome; however, an optimal I:E ratio is unknown. METHODS: To assess for an optimal I:E ratio, hemodynamic, ventilatory, and oxygenation parameters were determined in eight adult trauma patients with acute respiratory distress syndrome supported with pressure-control ventilation. An indwelling pulmonary artery catheter facilitated the extensive measurements as I:E ratios were randomly changed between 1:1 and 3:1. Measurements were determined 30 minutes after each change in the I:E ratio. RESULTS: Increasing the percentage of inspiratory time resulted in a progressive increase in arterial oxygenation (p < 0.05) in conjunction with elevations in mean airway pressure (p < 0.05) and a decrease in alveolar-arterial oxygen difference (p < 0.05). Furthermore, progressive reversal of the I:E ratio significantly diminished alveolar ventilation (p < 0.01), with worsening dynamic compliance (p < 0.01). There were no demonstrable changes in hemodynamics. CONCLUSION: These findings demonstrate the effectiveness of increasing inspiratory time to improve oxygenation, yet to the detriment of ventilation. This suggests that within the parameter confines of this study, the preferential I:E ratio is a balance between oxygen demands and ventilatory requirements.

Outcome and cost analysis for outpatient skin grafting.

BACKGROUND: To reduce cost, outpatient surgery is advocated when feasible; however, the potential of compromising outcome is a concern. The purpose of this review is to assess patient outcome and cost for managing operative burn injuries without hospitalization. METHODS: During the past 18 months, 54 patients were identified with burns amenable to operative debridement and skin grafting without hospitalization. Twenty patients chose to be hospitalized and underwent prompt skin grafting. Operative skin grafting as an outpatient was chosen by the remaining 34 patients. Of these, four patients were subsequently hospitalized postoperatively (two for pain, one for cellulitis, and one for vomiting). RESULTS: Hospitalized patients and outpatients were similar in age and extent of burn; however, those hospitalized underwent skin grafting sooner after injury (2.1 +/- 0.4 days for inpatients vs. 11.5 +/- 0.8 days for outpatients; mean +/- SEM). Inpatients also had a significantly larger area skin-grafted (286 +/- 24 cm2 for inpatients vs. 178 +/- 14 cm2 for outpatients). Graft take was very good in each group. Cost, as indexed by patient charge, was substantially less for outpatients ($2,397 +/- $222) than for inpatients ($17,220 +/- $410). CONCLUSION: These results demonstrate a significant cost reduction with nonhospitalized operative care of burn injuries without any overt detriment in outcome, thus endorsing outpatient skin grafting when amenable. This review also illustrates that delaying operative intervention reduces the burn area required for grafting.

Assessment of human colon cancer protein kinetics in vivo.

BACKGROUND: Malignancies enlarge because protein synthesis exceeds the rate of breakdown; however, the specific protein kinetic pattern remains unknown. Determining in vivo protein kinetic rates for a tumor may be useful for quantifying individual responses to a specific therapy. The aim of this study was to assess whether the growth of tumors is related to an increase in protein synthesis or an inhibition of protein breakdown. METHODS: Five patients (age, 59 +/- 3 years) with adenocarcinoma of the colon undergoing colonoscopy were studied. Tissue protein synthesis and breakdown rates were measured in vivo for both segments of colon cancer and adjacent normal-appearing colonic mucosa by using a primed, continuous infusion of 1(13)C leucine with tissue biopsy and quantitation of regional blood flow by laser Doppler flowmetry. RESULTS: Segments of colon cancer had a significantly (p < 0.05) greater rate of protein synthesis as quantitated by both the fractional rate of protein synthesis (Ca 45.4% +/- 5.0%/day versus nl mucosa 35.7% +/- 3.1%/day; mean +/- SEM) and by the tissue synthesis rate (Ca 69.4 +/- 9.0 versus nl mucosa 51.6 +/- 5.2 mumol/L leucine/day/100 gm tissue). Regional blood flow was significantly elevated in the cancer (Ca 110.9 +/- 5.8 versus nl mucosa 91.2 +/- 2.9 ml/min/100 gm), which contributed to commensurate rates of tissue breakdown (Ca 28.6 +/- 2.0 versus nl mucosa 28.2 +/- 2.4 mumol/L leucine/day/100 gm). CONCLUSIONS: These results illustrate that human colon cancers grow in vivo as a result of increases in protein synthesis. Furthermore, increases in regional blood flow limit the rate of tissue protein breakdown of colon cancer, thereby contributing to growth of the malignancy. These findings support the contention that therapeutic strategies aimed at negating this inherent increase in protein synthesis or limiting blood flow may effectively limit the growth of malignancies. This methodology may also provide an index for evaluating the effectiveness of future therapies aimed at reducing tumor growth for individual patients.

Infusion of hot crystalloid during operative burn wound debridement.

BACKGROUND: Hypothermia exacerbates coagulopathy and is thus a potentially devastating morbidity during operative debridement of burn wounds. Current techniques for maintaining body temperature include warming intravenous fluids at 38 degrees C. The purpose of this study was to assess the safety of infusing saline heated to 55-60 degrees C. METHODS: Using a modified fluid warmer, saline heated to 60 degrees C was infused through central venous access in eight adult patients undergoing debridement of burn wounds. The temperature of the saline actually entering the patient was measured by a thermocouple attached at the connection to the central line catheter. RESULTS: The actual infusate temperature was 54.0 +/- 1.2 degrees C. Over the first hour, 1,100 mL of hot saline was given, thus delivering 17.6 kcal more heat than fluid warmed to the traditional 38 degrees C. Core temperature measured via esophageal and Foley catheters had an insignificant trend toward increase during the operative procedure. There was no evidence of intravascular hemolysis or coagulopathy. CONCLUSION: This pilot study suggests that infusion of hot crystalloids given via central venous access is safe and may be an acceptable adjuvant in attenuating hypothermia during operative procedures.

Lactic acidosis during sepsis is related to increased pyruvate production, not deficits in tissue oxygen availability.

OBJECTIVE: The purpose of this study was to quantitate the derangements in intermediary carbohydrate metabolism and oxygen use in severely septic patients in comparison with healthy volunteers. SUMMARY BACKGROUND DATA: It commonly has been assumed that the development of lactic acidosis during sepsis results from a deficit in tissue oxygen availability. Dichloroacetate (DCA), which is known to increase pyruvate oxidation but only when tissue oxygen is available, provides a means to assess the role of hypoxia in lactate production. METHODS: Stable isotope tracer methodology and indirect calorimetry was used to determine the rates of intermediary carbohydrate metabolism and oxygen use in five severely septic patients with lactic acidosis and six healthy volunteers before and after administration of DCA. RESULTS: Oxygen consumption and the rates of glucose and pyruvate production and oxidation were substantially greater (p < 0.05) in the septic patient compared with healthy volunteers. Administration of DCA resulted in a further increase in oxygen consumption and the percentage of glucose and pyruvate directed toward oxidation. Dichloroacetate also decreased glucose and pyruvate production, with a corresponding decrease in plasma lactate concentration. CONCLUSIONS: These findings clearly indicate that the accumulation of lactate during sepsis is not the result of limitations in tissue oxygenation, but is a sequelae to the markedly increased rate of pyruvate production. Furthermore, the substantially higher rate of pyruvate oxidation in the septic patients refutes the notion of a sepsis-induced impairment in pyruvate dehydrogenase activity.

Surgically placed gastro-jejunostomy tubes have fewer complications compared to feeding jejunostomy tubes.

OBJECTIVE: During laparotomy, jejunostomy tubes (J tubes) are often placed to provide access for enteral nutrition in the immediate postoperative period. However, the placement of such tubes may be associated with potentially devastating intra-abdominal complications possibly related to the tenuous security of a tube through the small bowel wall. An alternative method for enteral nutrition access is to surgically place a "PEG-J" tube (i.e., surgical G/J tube) thus providing for jejunal feedings via a gastrotomy without a jejunotomy. The purpose of this study is to assess whether surgically placed G/J tubes reduce the postoperative complications in comparison to feeding J tubes. METHODS: Over the past 18 months, 92 J tubes and 56 G/J tubes were placed during laparotomy at a single institution and the method chosen by surgeons' preference. The frequency of complications associated with each tube was determined by review of the postoperative medical records. RESULTS: There was no enteric leakage in those patient given G/J tubes (p < 0.05). Furthermore 10% of the patients receiving J tubes required operative repair of a J tube complication while no patient with an access complication following G/J tube placement required surgical repair (p < 0.05). CONCLUSIONS: These results demonstrate that operative positioning of a jejunal feeding tube through a gastrostomy tube (surgical G/J tube) provides a safer route for enteral nutrition than does direct tube placement via the jejunal wall, by significantly reducing both the incidence of enteric leakage and the requirement for operative repair.