The in vivo availability of gentamicin when admixed with total nutrient solutions: a comparative study.

The relative in vivo availability of gentamicin when administered by two different intravenous methods was evaluated in patients treated in a surgical intensive care unit in a randomized, prospective, crossover study. Each patient received gentamicin therapy via intravenous piggyback (IVPB) and in-line burette (ILB) methods. In the IVPB method, the drug was mixed in 5% dextrose in water (D5W) and infused intermittently. In the ILB method, the drug was mixed using the patient's total nutrient admixture (TNA) solution as the diluent in an ILB, which was inserted between the TNA bottle and its administration set and infused intermittently. A serial sampling of four sets of serum concentrations of the gentamicin was obtained. Pharmacokinetic parameters (Kel, Vd, and a maximum serum concentration) were calculated from the four sets of concentrations collected per patient. The IVPB method yielded mean values of Kel, Vd, and C1.5mg/kg of 0.13 hr-1, 0.39 liter/kg, and 5.1 micrograms/ml, respectively. The ILB method yielded mean values of Kel, Vd, and C1.5mg/kg of 0.14 hr-1, 0.34 liter/kg, and 5.6 micrograms/ml, respectively. A t-test for paired samples was applied to these mean values. Significant difference was not found (p greater than 0.05). The intermittent infusion of gentamicin, using TNA as the diluent and an ILB, produced equivalent serum concentrations when compared with D5W as the diluent.

Growth of microorganisms in total nutrient admixtures.

It has been reported that intravenous fat emulsions, because of their isotonicity and neutral pH, support microbial growth, but traditional parenteral nutrition solutions, being hypertonic and more acidic, are not as supportive. To date, few studies have documented microbial growth in total nutrient admixtures (TNA) containing dextrose, amino acids, fat, electrolytes, vitamins, and trace elements. This study was undertaken to analyze the growth of Staphylococcus aureus, Candida albicans and four gram-negative enteric bacilli in three different nutrient admixtures, with and without the inclusion of 5% fat emulsion. The composition of the admixtures was either 5, 10, or 25% dextrose; either 0 or 5% fat; and 3% amino acids, electrolytes, vitamins, and trace elements. All admixtures were innoculated with 100 colony-forming units per milliliter, incubated at room (25 degrees C) or refrigerated (4 degrees C) temperature, with samples withdrawn at 0, 3, 6, 12, 24, and 48 hours and plated in triplicate. Only C. albicans demonstrated any significant growth regardless of fat content. The pH of the admixtures was similar (acidic), and all solutions were hypertonic and found to inhibit bacterial growth. Conclusions suggest that TNA, when formulated with normal concentrations of additives, is no more likely to support growth of contaminant organisms than the traditional solutions. This contradicts the notion that the addition of fat to total parenteral nutrition will enhance the ability of these admixtures to support microbial growth.

Effect of die spacer on the seating of complete cast gold crowns with grooves.

Fifty crowns were constructed with an indirect technique for a standardized Ivorine tooth preparation to determine whether casting relief would improve the seating of complete cast crowns with zinc phosphate cement. The variables were two grooves in the preparations and die spacer casting relief of approximately 20 to 40 micron. The tooth preparations of two groups had no grooves, but castings were made with internal relief for only one group. Three groups had buccal and lingual grooves in the preparation. One group had no relief, a second group had complete relief, and a third group had relief but not in the grooves. The discrepancies noted before and after cementation of the castings were measured. The average discrepancy for each group and the significance between groups was determined. Results of this study demonstrated the following. Die relief significantly improved the seating of complete cast-gold crowns with or without grooves. Omitting die spacer from grooves did not reduce the benefits of relieving the remainder of the die. Partial internal relief was better than no relief. The grooves did not disrupt seating when die spacer application was complete or specifically omitted from the grooves alone.

Pharmacist-directed heparin therapy using a standard dosing and monitoring protocol.

Use of a protocol for pharmacist determination of heparin sodium dosages administered by continuous i.v. infusion was evaluated by retrospective chart review in a California hospital. Charts of adult medical-surgical patients who received heparin infusions between June 1982 and December 1983 were reviewed for the following information: patient sex, age, and reason for receiving heparin; times, dates, numbers, and values of coagulation tests before and during heparin therapy; times, dates, and values of prothrombin time determinations during conversion to warfarin therapy; and times, number, and costs of heparin infusions. Charts were divided into two groups: those of patients for whom physicians prescribed heparin doses empirically and those of patients for whom physicians requested heparin dosing by the pharmacy department. Data were evaluated for 62 patients in the physician-dosed group and 26 patients in the pharmacy protocol group. Pulmonary embolism was the reason for heparin therapy in 34% of the physician-dosed patients and only 15% of the pharmacist-dosed patients. Pharmacists using the protocol ordered fewer anticoagulation tests and fewer heparin infusions per patient. Time from the start of heparin therapy to therapeutic anticoagulation was shorter in patients whose heparin dose was determined by the protocol, and values in the therapeutic range were achieved in a greater percentage of these patients than in the empirically dosed patients. Pharmacists using a standard dosing protocol effectively initiated and maintained heparin therapy that compared favorably with physician-dosed empiric therapy.

Comparison of the multiphasic dysfunction profile with lateral transcranial radiographs.

Lateral transcranial radiographs of 926 patients were analyzed for condylar position, TMJ space, and obvious condylar morphologic changes. Differences in condylar position and joint space variations were noted between men and women. An increase in nonconcentric condylar position, joint space variations, and condylar morphologic changes were found with advancing age. There was a significant correlation of condylar position, joint space variations, and condylar morphology with mandibular dysfunction profile scores. Mandibular dysfunction is manifested by a wide range of signs and symptoms, none of which is always present with the disorder. Although TRs are limited in their total diagnostic value, their use in discerning major TMJ changes serves as an important adjunct in the examination and diagnosis of mandibular dysfunction.

Long-term follow up of transoral rib grafts for mandibular atrophy.

Nineteen patients who had autologous rib grafts for mandibular augmentation were monitored for six to 13 years to evaluate the rate of resorption as a function of time. Data were collected from panoramic radiographs that were corrected for distortion. The findings indicated that rapid resorption occurs during the first two years after grafting and decreases markedly thereafter. Although some prolonged benefits resulted from the procedure, it was concluded that it is not an ideal solution to the problem of ridge augmentation.

Clinically significant factors in dowel design.

When a method of intracoronal reinforcement is selected, many factors must be weighed. The hazards include (1) the induced stresses and the risk of fracture during placement of the dowel, (2) the probability of root perforation during post space preparation, (3) the wedging action of tapered dowels, and (4) the incidence of fracture with self-threading pins in devitalized teeth. The amount of tooth structure that remains after endodontic therapy and post space preparation is paramount. Endodontic and restorative treatment must be aimed at preserving tooth structure to provide strength and resistance to fracture of the pulpless tooth. To fabricate a large-diameter dowel with a strength that greatly exceeds that of the endodontically treated root decreases the prognosis for clinical success.

The prevalence of mandibular dysfunction. Part II: A multiphasic dysfunction profile.

The frequency of occurrence of 20 signs and symptoms commonly associated with mandibular dysfunction was used to numerically rate the clinical severity of mandibular dysfunction. Some signs and symptoms had a clearly direct relationship whereas other signs demonstrated a diminished direct relationship, no relationship, or an inverse relationship in advanced dysfunction stages. Further study is needed to determine if there exists an exact relationship of some clinical signs to mandibular dysfunction.

The prevalence of mandibular dysfunction. Part I: Sex and age distribution of related signs and symptoms.

This study concludes the following: 1. Mandibular dysfunction is extensive. 2. Age and sex differences are apparent with various signs and symptoms. 3. Women and younger patients tend to respond positively more often than men and older patients to questions relating to subjective TMJ and muscle symptoms. 4. Objective TMJ and occlusal signs show little age or sex differentiation. 5. Positive responses to questions regarding bruxism were more common in men. 6. Age and sex differences in the prevalence of mandibular dysfunction may be influenced by the method of investigation (anamnestic versus clinical examination) and by the signs and symptoms selected to be representative of this disorder. When compared with the findings of earlier investigations, the conclusions suggest that social, cultural, psychologic, sex, and age differences contribute to the responses to questions pertaining to mandibular dysfunction. However, this may not be an accurate reflection of the prevalence of mandibular dysfunction since the objective signs do not show the age and sex differences that the subjective symptoms indicate. Therefore, additional studies are needed to correlate all data to establish a more reliable profile of both signs and symptoms of mandibular dysfunction.

A comparison of gingival inflammation related to retraction cords.

Potassium aluminum sulfate, aluminum chloride, and 8% racemic epinephrine did not demonstrate practical differences, although potassium aluminum sulfate produced fewer inflammatory changes than the other agents. 2. It appears that factors other than the chemical agent (e.g., physiologic differences in patients) may play a role in the amount of gingival inflammation induced. 3. Additional studies using a larger sample size and an untreated control site should be undertaken.

An 18-month clinical evaluation of semiprecious and nonprecious alloy restorations.

SEM studies indicate that the control alloy, Minigold, WLW, and Litecast metals presented similar results in relation to marginal fit when proper techniques are followed. Clinical evaluation based on the criteria of gingival irritation, patient sensitivity, and abrasion demonstrated no statistically significant differences between the casting alloys tested and the control. The control alloy had significantly fewer restorations with tarnish and corrosion than either WLW or Litecast. There was no significant difference between the control alloy and Minigold in terms of tarnish and corrosion.

Clinical research in dental institutions as reported in selected dental journals.

This study provided data on the amount of research reported by dental institutions to dental journals between 1960 and 1979 in the areas of oral surgery, pathology, endodontics, periodontics, prosthodontics, and pedodontics.