Analysis of the practice of nutrition support pharmacy specialists.

In 1988 the Board of Pharmaceutical Specialities (BPS) recognized nutrition support pharmacy practice (NSPP) as one of four specialty areas in pharmacy. The BPS appointed a specialty council to develop and manage the process for board certification of qualified specialists. One step was to identify and validate activities performed by the specialists. This was accomplished by conducting a study that delineated the role of these practitioners and also provided information for developing a blueprint for a certification examination. The results revealed the types of practice settings, education, and training for specialists, and the distribution of professional time devoted to nutrition support activities.

Nutrition support for lung transplant patients.

Lung transplantation has emerged as an established and accepted therapy for patients with endstage pulmonary disease. Very little information has been published about the nutrition management of these patients during the period after transplantation. We conducted a retrospective review of the nutrition support records of 52 adult patients who had undergone lung transplantation at our institution. In addition to patient demographics, data were collected on baseline nutritional status, energy and protein goals, type of specialized nutrition support therapy, length of therapy, and incidence of metabolic complications. More than 50% of the patients receiving lung transplants had a diagnosis of cystic fibrosis. Compared with patients having other diagnoses, this group of patients had a greater incidence of malnutrition. The mean energy goal was 127 +/- 0.07% of basal energy expenditure, and the protein goal was 1.37% +/- 0.25 g/kg/d. All patients received parenteral nutrition therapy, which was begun by postoperative day 2 for more than 70% of the patients. Therapy was short-term (mean, 9 days), and patients then received oral diet. The most common metabolic complications were azotemia, hyperglycemia, and hypomagnesemia. Our experience should provide assistance to other health care professionals who are involved in the nutrition and metabolic management of patients undergoing lung transplantation.

Drug-lab interactions: implications for nutrition support. Acetylcysteine interference with urine ketone test.

It is important that health care professionals be aware of the potential for medications to interfere with clinical laboratory tests. Medications can cause in vivo effects when the concentration or activity of the analyte is altered before the analysis and therefore the assay result is true and accurate. An in vitro effect occurs when the medication interferes with the assay, and the result is erroneous and cannot be interpreted. This report describes a recently identified case of interference of acetylcysteine with the urine test for ketones and demonstrates the importance of a thorough medication review in evaluating abnormal laboratory tests.

Restoring patency of long-term central venous access devices.

More patients are receiving extended and complex infusion therapies, so there is an increased need for long-term central venous access and the placement of "permanent" central venous access devices (CVADs). CVADs may be necessary for home parenteral nutrition and chronic intravenous antibiotics, chemotherapy, analgesia, and hydration therapies. The use of these catheters for multiple therapies increases the potential for catheter occlusion. Occlusions may be secondary to thrombosis, lipid deposits, or the precipitation of medications or minerals and electrolytes. Various pharmacologic agents have been used to restore patency of occluded CVADs. These agents include thrombolytics, ethyl alcohol, hydrochloric acid, and sodium bicarbonate. A thorough evaluation of the CVAD and the therapies administered via this catheter is necessary to select the most appropriate pharmacologic agent to restore catheter patency.

Effect of retrograde aminophylline administration on calcium and phosphate solubility in neonatal total parenteral nutrient solutions.

The effect of retrograde administration of aminophylline injection on calcium and phosphate solubility in neonatal total parenteral nutrient (TPN) solutions was studied. Neonatal TPN solutions containing two amino acids solutions in three concentrations (Travasol 1% and 2% and TrophAmine 2%) were formulated. Calcium and phosphate salts were added to achieve calcium concentrations of 10, 15, 20, 25, 30, or 40 meq/L and phosphorus concentrations of 10, 15, 20, 25, 30, or 40 mmol/L. Samples were inspected visually after 18-24 hours; solutions free of precipitation were then infused through two parallel syringe-pump systems designed to simulate clinical conditions for TPN solution administration to a 1-kg neonate. To one system, a 7.5-mg aminophylline dose was added as a manual retrograde injection; sterile water for injection was added as a manual retrograde injection to the other system. The solutions were inspected throughout a one-hour infusion period for precipitate formation in the i.v. apparatus, and the pH of the effluents was determined. Concurrent aminophylline administration resulted in visible precipitate in all but a few of the solutions tested. The solution containing Travasol 2%, calcium 10 meq/L, and phosphorus 10 mmol/L remained clear, as did the solutions containing TrophAmine 2% and the following concentrations of calcium and phosphorus: calcium 10 meq/L and phosphorus 10, 15, or 20 mmol/L; calcium 15 meq/L and phosphorus 10 or 15 mmol/L; and calcium 20 meq/L and phosphorus 10 or 15 mmol/L. An average increase in pH of 0.63 unit was noted in all solutions.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy of tube feeding in supplying energy requirements of hospitalized patients.

During a 6-week period, all adult patients in a university hospital receiving ready-to-feed nasoenteric tube feeding formula were prospectively studied. The study objective was to determine each patient's caloric intake from tube feeding relative to their energy needs and to identify factors causing decreased feeding intake. Each of 35 patients was visited at least once daily to determine their volumetric intake of tube feeding formula. Daily review of patient care records and nursing interviews were used to identify interruptions in therapy. Patient's basal energy expenditures (BEE) were calculated using the Harris-Benedict equation. Calorie goals were set by members of the Nutrition Support Service or clinical dietitians. Intakes averaged 1095 +/- 41 Kcal (SEM) per day or 61% of their mean calorie goal of 1791 +/- 41 Kcal. Mean daily calorie intake was statistically different (p less than 0.05) from mean energy goal on patient study days 1 through 5, 7, and 8. Only 16 of the 35 patients achieved an intake of 100% of their energy goal on any day of therapy. Calorie goals averaged 1.4 times BEE. Mean daily calorie intake did not exceed BEE until study day 10. Eighteen % of potential feeding time was lost due to temporary feeding interruptions; primarily inadvertent extubation (4.6%), gastrointestinal intolerance (4.7%), medical procedures requiring discontinuation of feeding (2.8%), and feeding tube positioning difficulties (1.5%). In addition, physicians ordered only 75% of calculated energy goals. These data indicate that tube feeding therapy, when provided under usual hospital conditions, does not meet patient's energy requirements.

Effects of enteral tube feeding on the absorption and pharmacokinetic profile of carbamazepine suspension.

In a randomized, two-period crossover clinical study, eight normal male volunteers received two separate 500-mg doses of carbamazepine (CBZ) suspension 1 week apart. One dose was administered orally after an overnight fast, and the other was administered by nasogastric feeding tube during a continuous enteral feeding infusion. Serial serum CBZ concentrations were determined by high-performance liquid chromatography (HPLC) to assess the effects of the enteral feeding on CBZ absorption. Noncompartmental methods were used to estimate pharmacokinetic data. One volunteer experienced a mild hypersensitivity reaction after his first CBZ dose and was withdrawn from the study. The other subjects tolerated both doses very well, although most experienced mild drowsiness or lightheadedness. Serum CBZ concentrations were lower during enteral feeding administration, but the differences were statistically significant only at 8 h (p = 0.044). Changes in pharmacokinetic data were not significant, although the decrease in maximum serum concentration approached significance (p = 0.052). The relative bioavailability of CBZ suspension with enteral feeding administration was 90.1% of that during fasting. There was a strong correlation between CBZ dose (mg/kg) and Cmax after oral administration (r = 0.97, Y = 1.88X - 4.49, p less than 0.001) but not during enteral feeding administration. Although absorption of CBZ suspension was generally slower and slightly diminished during nasogastric feeding, this interaction may lessen unwanted side effects.

Nonlinear ethotoin kinetics.

Five healthy subjects were given single 500-, 1500-, and 2500-mg doses of ethotoin as 250-mg tablets at 7-day intervals. Plasma samples were collected for 49 hr after dosing and were assayed by HPLC for ethotoin. The drug was more slowly absorbed after the two higher doses. There was a disproportionate increase in AUC in all subjects with the escalating doses. Individual subject data were fitted to a first-order model and one incorporating Michaelis-Menten elimination kinetics. Eleven of the 15 data sets were best described by the nonlinear model. All subjects reported visual disturbances with the two higher doses, and four of five experienced dyscoordination of gait with the 2500-mg dose. These effects did not appear to be related to plasma ethotoin concentration.