Is there a role for albumin administration in nutrition support?

OBJECTIVE: To review the administration of exogenous albumin in patients receiving nutritional support and determine if the use of albumin is supported by controlled trials. DATA SOURCES: MEDLINE search of English-language literature using the key terms albumin, parenteral nutrition, and enteral nutrition. The references of articles identified were also searched. STUDY SELECTION: Studies examining the administration of exogenous albumin to hypoalbuminemic patients receiving nutrition support. DATA EXTRACTION: Results from prospective randomized trials are presented in detail. Data from noncontrolled and animal studies are presented in areas where human controlled trials are limited. DATA SYNTHESIS: Albumin is a marker of malnutrition and numerous studies have demonstrated that a low serum albumin concentration is associated with increased morbidity and mortality. Investigators have attempted to improve outcome through the administration of exogenous albumin. The results of controlled trials examining exogenous albumin administration have been equivocal. One study demonstrated a significant decrease in overall complications, pneumonia, and sepsis. In two other controlled trials, albumin administration failed to decrease complications. None of the studies demonstrated a significant decrease in mortality or length of stay. A low serum albumin concentration has also been linked to intolerance to enteral feedings. Although case reports and one study support the administration of albumin, two prospective controlled trials have failed to demonstrate improved tolerance to enteral feeding in hypoalbuminemic patients receiving exogenous albumin. CONCLUSIONS: Evidence to date is insufficient to support the routine administration of exogenous albumin to hypoalbuminemic patients receiving nutrition support.

Criteria for use of total parenteral nutrition administered by a central venous catheter in adults. Presbyterian Hospital, Albuquerque, New Mexico.

Criteria for a utilization review of total parenteral nutrition administered by a central venous catheter are presented. Areas covered include: indications and contraindications for use, appropriate monitoring criteria, complications related to parenteral nutrition, dosing, and outcome of therapy.

Effect of the mode of lipid administration on parenteral nutrition-related infections.

OBJECTIVE: To determine if total nutrient admixtures (TNAs) influence the rate of infection in clinical practice. DESIGN: Prospective, randomized trial. SETTING: Department of Veterans Affairs Medical Center. PATIENTS: All patients were administered parenteral nutrition (PN) via a central venous catheter and received daily lipids. INTERVENTION: Patients were randomized as to the mode of administration of lipids. Lipids were either administered with other PN components in a TNA or were piggybacked (PB) into the PN solution. MAIN OUTCOME MEASURES: Treatment groups were compared for the rate of occurrence of PN-related infections. Infections were classified as catheter infections or catheter sepsis. RESULTS: Ninety-eight patients were entered into the trial. Data from 96 patients (44 TNA, 52 PB) were available for analysis. Treatment groups were well matched for age, baseline albumin, days of PN, predicted basal metabolic rate, and calorie and protein requirements. TNA patients received a significantly greater percentage of nonprotein calories as lipid. The incidence of infection was 12.6 and 10.3 per 1000 days of PN in the TNA and PB groups, respectively (p = 0.89). The microorganisms responsible for infection and the type of infections that developed were similar in both groups. CONCLUSIONS: Use of TNAs does not influence the rate of infection in patients receiving PN.

The effect of doxycycline on serum levels of ethinyl estradiol, norethindrone, and endogenous progesterone.

Doxycycline and other antibiotics have been implicated in oral contraceptive (OC) failure, but information is sparse and studies of a doxycycline-OC interaction are nonexistent. Because an interaction between doxycycline and OCs, especially those containing low-dose estrogen, could result in an unplanned and unwanted pregnancy, a controlled clinical trial of the effects of doxycycline on OC hormone concentrations was performed. Twenty-four women aged 18-35 years were recruited as volunteers from among the patients seen in a University-based family planning clinic. While they were on a steady dose of the OC Ortho-Novum 1/35, serum concentrations of ethinyl estradiol, norethindrone, and endogenous progesterone were measured on days 18, 19, and 20 of the menstrual cycle (control phase). These measurements were repeated on days 18, 19, and 20 of the following menstrual cycle while the patient was taking doxycycline, 100 mg twice daily (treatment phase). No statistically significant differences in serum levels of ethinyl estradiol, norethindrone, or endogenous progesterone were seen between the control and treatment phases. However, there was large inter-patient and intra-patient variability in ethinyl estradiol and norethindrone levels. No elevations of endogenous progesterone occurred to suggest ovulation during antibiotic administration in either phase. It is not known what effects longer or earlier administration of doxycycline during the OC cycle would have on serum hormone concentrations or ovulation. Pregnancies attributed to failure of OCs because of tetracycline use could in fact be due to other causes or could represent a true interaction that only manifests itself in a small proportion of women at risk.

Therapeutic drug monitoring: improved performance through educational intervention.

A pilot study done at our institution and previous studies in the literature indicate that therapeutic drug monitoring (TDM) is frequently performed without a proper indication. In addition, samples are often improperly collected or interpreted by physicians. The purpose of this study was to determine if a pharmacy-based educational intervention could positively influence the performance of TDM in a teaching institution. A cost-savings analysis on the reduction of drug levels not indicated or improperly sampled was also performed. The study consisted of a preliminary data collection period, an educational intervention, and a postintervention data collection period. The pre- and posteducational intervention periods consisted of a 1-month concurrent review of aminoglycosides, digoxin, and theophylline serum levels. The educational intervention consisted of in-service programs and newsletter. There were 188 and 211 serum drug levels analyzed during the pre- and postintervention periods, respectively. Overall, the educational intervention significantly increased the number of drug levels obtained for rational indications, correctly sampled and appropriately interpreted by physicians (p less than 0.001, chi 2 analysis). Cost savings associated with this program was +2,788 in patient charges (+559 in hospital costs) per month. This study demonstrated that TDM may be significantly improved through education.

Time to steady state following a change in dosing rate.

Drugs administered at fixed intervals or by continuous infusion will accumulate in the body until steady state is achieved. The time to a given percentage of the eventual steady-state concentration has previously been considered to be dependent only on the elimination half-life. This is incorrect. Although the rate of drug accumulation in the body is dependent only on the elimination half-life, the time to a given percentage of steady state is dependent on both the elimination half-life of the drug and the initial concentration. This paper presents the mathematical proof of this concept, computer simulations demonstrating the use of these equations, and nomograms for use in clinical practice. The use of this method allows serum drug concentrations to be evaluated earlier than previously predicted after changes in the dosing rate.

Nonsteroidal antiinflammatory drug-induced renal dysfunction related to inhibition of renal prostaglandins.

This article reviews the role of prostaglandins (PG) in maintaining renal function in the face of vasoconstrictive substances and decreased renal blood flow. Inhibition of the synthesis of renal PG by nonsteroidal antiinflammatory drugs (NSAID) may lead to the development of hemodynamically induced renal dysfunction in patients with a decreased effective plasma volume or chronic renal insufficiency. The importance of stimulation of renal PG activity to the action of diuretics and a pharmacodynamic mechanism for NSAID-induced diuretic resistance are presented. Evidence for the relative selectivity of sulindac in inhibiting systemic PG without inhibiting renal PG is also reviewed. Inhibition of renal PG synthesis has been postulated to be a contributing factor for other forms of NSAID-induced renal dysfunction (interstitial nephritis, analgesic-associated nephropathy). The relationship between renal PG inhibition by NSAID and these syndromes is briefly discussed. Considering the frequent use of NSAID, it is important that practitioners are aware of the mechanisms whereby patients may develop NSAID-induced renal dysfunction and that they are able to identify patients at risk.

Management considerations in treating metabolic abnormalities associated with theophylline overdose.

We treated a patient who intentionally overdosed with theophylline complicated by metabolic disturbances. Management of the patient's hypokalemia with moderate doses of potassium chloride resulted in hyperkalemia with associated electrocardiographic changes. The rapid clearance of theophylline due to the administration of oral activated charcoal was believed to be a contributing factor. It is likely that theophylline-induced hypokalemia is due to intracellular sequestration of potassium and that as the theophylline level decreases potassium will reequilibrate out of the cell. The case provides support for the conservative management of metabolite abnormalities associated with theophylline overdose.

The growth of microorganisms in total parenteral nutrition admixtures.

Total nutrient admixtures (TNAs) containing glucose, amino acids, and lipid emulsion in one container and amino acid/dextrose solutions [conventional total parenteral nutrition (TPN) formulations] were studied in a controlled laboratory experiment for their ability to support the growth of microorganisms. Both TNA and conventional TPN formulations for peripheral and central venous administration with standard additives were inoculated with microorganisms to provide 10(1)-10(2) colony-forming units/ml (CFU/ml) of Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Candida albicans. The admixtures were stored at room temperature and samples for quantitative microbiology were taken at time 0, 6, 12, 24, 48, 72, and 96 hr. K. pneumoniae, E. coli, and P. aeruginosa were able to proliferate in central TNAs, but the growth of these organisms was retarded in conventional TPN solutions. In the peripheral formulations, K. pneumoniae and E. coli proliferated in both the TNA and conventional TPN systems, whereas P. aeruginosa grew well only in the peripheral TNA. S. epidermidis was not able to grow in any admixtures tested; however, C. albicans grew well in all admixtures, but growth was slower in the conventional central TPN. In conclusion, peripheral and central TNAs supported the growth of microorganisms significantly better than conventional TPN solutions.

Cimetidine absorption in humans during sucralfate coadministration.

Cimetidine absorption after a single 300 mg oral dose was evaluated in six normal subjects in the absence or presence of sucralfate. Sucralfate was ingested four times a day for 2 days prior to and for two additional doses on the day of cimetidine ingestion. Sucralfate coadministration had no statistically significant influence on the rate or extent of cimetidine absorption.