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J L Mullen

Publications and source records attributed to J L Mullen.

153 records · Page 9Linked to original sources
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Pentobarbital improves nitrogen retention in sepsis.

Pentobarbital therapy has been associated with decreased urinary nitrogen excretion and resting energy expenditure in stressed patients. The metabolic effects of pentobarbital in sepsis were investigated in 29 well-nourished rats who underwent superior vena caval cannulation, cecal ligation, and puncture. Animals were randomly assigned to receive either a continuous infusion of 20 mg/kg/day of pentobarbital combined with parenteral nutrition (n = 13) or parenteral nutrition alone (n = 16). Both groups received isocaloric, isonitrogenous parenteral nutrition postoperatively for 24 hr. Mean nitrogen balance (+/- SEM) was better in the pentobarbital group (+169 +/- 76 mg/kg/day vs -190 +/- 66 mg/kg/day, p less than 0.01). No significant differences between the pentobarbital and control groups were noted for urinary 3-methylhistidine excretion (9 +/- 0.7 micrograms/kg/day vs 11 +/- 0.6 micrograms/kg/day, respectively) or 24 hr survival (77% vs 69%, respectively). Pentobarbital improves nitrogen retention without decreasing urinary 3-methylhistidine excretion in septic rats.

Animals↗
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Effects of nonglucose substrates (xylitol, medium-chain triglycerides, long-chain triglycerides) and carnitine on nitrogen metabolism in stressed rats.

To evaluate the efficacy of nonglucose energy substrates in promoting nitrogen retention and survival in stressed states, two series of studies were done. In study 1, 50 rats underwent cecal ligation/perforation and subsequent infusion for 24 hr with one of four isocaloric (220 kcal/kg/day), isonitrogenous (1.4 g/N/kg/day), isovolemic regimens which differed in caloric source: Glucose (GLU) + long-chain triglycerides (LCT) (50%:50%), GLU + LCT + medium-chain triglycerides (MCT) (50%:32%:18%), GLU + LCT/Carnitine (10 mg/dl) or GLU + LCT + Xylitol (XYL) (33%:33%:33%). The nitrogen-sparing effect of GLU + LCT was not enhanced by the addition of carnitine to facilitate LCT mitochondrial uptake or by MCT to bypass carnitine-dependent transport. In contrast, relative to GLU + LCT GLU + LCT + XYL decreased urinary 3-methylhistidine (3MH) excretion (p less than 0.01), and enhanced nitrogen retention (p less than 0.01 vs GLU + LCT). For study 2, 24 male rats were anesthetized, cannulated for TPN, and given a 25% burn. They were then randomized into three dietary groups. The diets were isocaloric (103 kcal/kg/day) and isonitrogenous (2.0 g N/kg/day) but differed in nonprotein calorie source: GLU + LCT (51%:49%), GLU + Glycerol (51%:49%) and XYL + LCT (51%:49%). As in the septic animals, N balance was best with the xylitol regimen (p less than 0.01). The polyol, xylitol, appears to have a significant nitrogen sparing effect in stressed animals.

Animals↗
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Antibiotic therapy of catheter infections in patients receiving home parenteral nutrition.

Fifty-eight episodes of catheter-related sepsis in 21 patients receiving home parenteral nutrition were retrospectively studied. Of 81 organisms isolated from the blood, 59% were Gram-positive cocci, 25% were Gram-negative bacilli, and 16% were yeast. Attempts to treat bacterial infections at home with antibiotic therapy while the catheter remained in place were made; fungal isolation resulted in immediate hospitalization and catheter removal. Gram-negative infections more often resulted in eventual hospitalization (92%) and catheter removal (50%) than Gram-positive infections (57% hospitalization and 23% catheter removal). Empiric therapy with 1 g of cefazolin intravenously every 12 hr was successful in only 33% of episodes caused by coagulase-negative staphylococci, whereas vancomycin was successful in 62%. Sensitivity testing was not a reliable guide for antibiotic choice for treatment of these infections. Cefazolin, 1 g, intravenously every 12 hr was successful in only 25% of Gram-negative episodes treated empirically with this regimen. We conclude that our home parenteral nutrition patients should be hospitalized for a few days upon presentation with a catheter infection for clinical evaluation and aggressive antibiotic therapy. Vancomycin is the preferred drug for treatment of catheter-related infections caused by coagulase-negative staphylococcus.

Bacterial Infections↗
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Efficacy of thrombolytic therapy for occlusion of long-term catheters.

Nineteen ambulatory outpatients requiring a tunneled central venous access device with catheter occlusion were studied. Mean catheter life was 7.9 +/- 8.2 months (range, from 1-36 months) at the time of the occlusion. Urokinase (5000 units/ml) was injected in sufficient amount to fill the internal volume of the catheter and allowed to stay for 5 to 10 min before attempting to aspirate. Repeated aspiration attempts were performed every 5 to 10 min for a maximum of 30 to 60 min or patency. In the event catheter patency was not restored, the thrombolytic solution was aspirated from the catheter and a maximum of two additional trials were instituted. Results included clearance of four out of 15 withdrawal occlusions (27%) and two out of four resistance to infusion occlusions (50%). Overall, successful catheter clearance occurred in six out of 19 occlusions (32%). The efficacy rate of thrombolytic therapy for successfully clearing occluded catheters at our institution using conventional low-dose thrombolytic therapy is markedly lower than previously reported rates of 57 to 100%. The reasons for this discrepancy may reflect differences in dosage of thrombolytic agent, method of administration, frequency of monitoring of catheter patency, and catheter life.

Catheterization, Central Venous↗
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The button jejunostomy for long-term jejunal feeding: results of a prospective randomized trial.

Low profile, self-retaining feeding conduits ("buttons") inserted percutaneously through a mature gastrostomy stoma are ideal for prepyloric feeding. We tested the efficacy of a surgically inserted button (Button, C.R. Bard, Inc) in the jejunum for long-term postpyloric feeding. Forty-two aspiration risk patients were prospectively randomized to receive a standard No. 14 French red rubber catheter (n = 21, mean age 68 +/- 17 years) or the button (n = 21, mean age 68 +/- 18 years). Common indications for jejunal feeding were aphagia due to obtundation (41%) and esophageal dysmotility (41%). All feeding devices were inserted 20 cm distal to the ligament of Treitz via a serosal tunnel (catheter) or double pursestring (button) technique. No patient required reoperation, and cardiopulmonary failure was the most frequent cause of death, occurring in 11 patients (26%). Goal feedings were obtained in 91% of the catheter patients and 100% of the button patients by postoperative day 4.7 +/- 1.9 and 4.2 +/- 2.2, respectively. At a follow-up of 43 +/- 13 days, 12 (92.3%) of 13 catheter patients and 9 (81.8%) of 11 button patients were receiving goal feedings. Three patients in the catheter group and four patients in the button group had resumed an oral diet. Device-related complications (dislodgment, occlusion, peritubular leak, or bowel obstruction) and total number of patients with complications were significantly lower in the button group (one [5%] vs eight [38%] for device-related complications and one [5%] vs six [29%] for incidence of complications for the button and catheter groups, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
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Long-term enteral access in aspiration-prone patients.

Aspiration pneumonia is a serious complication of enteral feeding. Many critically ill patients are particularly at risk for aspiration. Few studies have rigorously compared various access devices. Risk factors for aspiration and studies examining aspiration associated with enteral feeding devices are reviewed. We recommend a surgical jejunostomy for all patients at high risk for aspiration who require more than 3 weeks of enteral nutrition support.

Comorbidity↗