A controlled comparison of traditional feeding tube verification methods to a bedside, electromagnetic technique.

BACKGROUND: Benefits of enteral feeding are diminished by aspiration pneumonia and mechanical complications of misplaced feeding tubes. To avoid complications, clinicians determine the location of the tip before feeding. This study compares diagnostic test characteristics of 4 techniques for tip localization. METHODS: A prospective, blinded trial was conducted on the wards and critical care units of four acute-care hospitals. Patients requiring at least 3 days of enteral feeding were studied. Four observers at each institution used a randomly assigned technique to determine a tube's tip location. Methods included auscultation, aspiration with inspection or pH determination of aspirated material, and a recently developed electromagnetic technique. Results were compared with radiographic determination. Success rates were compared using sensitivity, specificity, and likelihood ratios. RESULTS: The 4 methods agreed with the radiograph in (mean, 95% confidence interval): 84 (80 to 88)%, 50 (45 to 55)%, 56 (51 to 61)%, and 76 (72 to 81)% of observations, respectively. Only the electromagnetic method and aspiration identified all tubes located above the diaphragm (negative likelihood ratio 0 and sensitivity 100%). Aspiration was unsuccessful in making a determination in 53% of the observations, whereas the electromagnetic method was successful 90% of the time.

Hospital care by hospital-based and clinic-based faculty: a prospective, controlled trial.

BACKGROUND: The hospital length of stay decreases and clinical outcomes are maintained when teaching hospitals involve hospital-based attending physicians in comparison with traditional attending physicians. The attending physician's time commitment, including the number of hours per day and months per year, required to achieve this result is unknown. This study compared the clinical outcomes and cost of care for patients treated by hospital-based and clinic-based attending physicians devoting dramatically different amounts of time to supervising residents on the medical wards of a suburban county hospital. METHODS: Patients were alternately admitted to 2 groups of ward teams. Faculty who attended 10 months of the year supervised one group. The comparison group's attending physicians were on service for 2 months or less and maintained clinic responsibilities while on service. The cost of patient care was compared by means of the length of stay, total hospital costs, and costs for ancillary services. Hospital mortality and readmission rates compared clinical outcomes. RESULTS: There were 4456 patients hospitalized on the medical wards of a teaching service. No differences were detected in the length of stay (4.37 +/- 0.1 days for hospital-based and 4.39 +/- 0.1 days for clinic-based attending physicians). Hospital cost was observed to be similar (average cost, $5989 and $5977 per patient, respectively). The clinical outcomes were equivalent, with adjusted mortality rates for hospital-based attending physicians of 3.2% vs 3.9% for clinic-based attending physicians (P =.28). CONCLUSION: An increase of faculty time and involvement for supervision of resident-managed hospital care did not improve clinical outcomes or decrease costs during the 1-year study period.

The incidence of ventilator-associated pneumonia and success in nutrient delivery with gastric versus small intestinal feeding: a randomized clinical trial.

BACKGROUND: Enteral feeding provides nutrients for patients who require endotracheal tubes and mechanical ventilation. There is a presumed increase in the risk of ventilator-associated pneumonia (VAP) with tube feeding. This has stimulated the development of procedures for duodenal intubation and small intestinal (SI) feeding as primary prophylaxes to prevent VAP. OBJECTIVE: To investigate the rate of VAP and adequacy of nutrient delivery with gastric (G) vs. SI feeding. DESIGN: A prospective, randomized, controlled trial. SETTING: A medical intensive care unit of a county hospital. PATIENTS: A total of 44 endotracheally intubated, mechanically ventilated patients requiring enteral nutrition. INTERVENTION: Subjects were randomized to receive enteral nutrition via G or SI feeding. Protocols directed the placement of the feeding tube and the infusion of enteral nutrition and defined the radiographic and clinical criteria for a diagnosis of VAP. MEASUREMENTS AND OUTCOMES: The incidence of VAP and the adequacy of nutritional supplementation were prospectively followed. The relative risk of VAP with SI was 1.1 (95% confidence interval 0.96-2.44) compared with G. The SI group received a greater percentage of their caloric requirements (SI 69 +/- 7% vs. G 47 +/- 7%, mean +/- SEM, p < .05). Mortality did not differ between G (26 +/- 9%) and SI (24 +/- 10, p = .86). CONCLUSIONS: There is no clear difference in the incidence of VAP in SI compared with G enteral nutrition. Patients given feeding into the SI do receive higher calorie and protein intakes.

The reliability of muscle function analysis using different methods of stimulation.

BACKGROUND: The purpose of our study was to determine the reliability of nonvolitional muscle function analysis (MFA) by determining the day-to-day and within-day reliability of conventional electrical stimulation and a newer, magneto-electrical stimulation method, using standard laboratory methodology. METHODS: Ten healthy, human immunodeficiency virus-negative adult men volunteered as subjects. MFA consisted of measuring the maximal relaxation rate, for magneto-electrical stimulation at 1 Hz and conventional electrical stimulation at 20 Hz, and force-frequency ratios using conventional electrical stimulation at 10 Hz:20 Hz and 10 Hz:50 Hz. Within-day and day-to-day reliability were determined by calculating the coefficient of variation (CV) for all subjects. RESULTS: Maximal relaxation rate using magneto-electrical stimulation had a significantly lower CV compared with the other nonvolitional MFA methods (p = .002). CONCLUSIONS: Maximal relaxation rate using magneto-electrical stimulation was more reliable and technically easier than the other muscle function parameters examined. However, the day-to-day CV of muscle function parameters is larger than traditional nutrition assessment techniques. Development within the field should strive to improve testing techniques so that the reliability of MFA will allow definition of a range of normal values against which an individual's value can be compared. Until this is available, the precision and reliability of MFA restrict its use to research and population studies.

Prospective evaluation of anticoagulant reversal with oral vitamin K1 while continuing warfarin therapy unchanged.

STUDY OBJECTIVES: To study the efficacy and safety of partially correcting therapeutic anticoagulation by administering oral vitamin K1. DESIGN: Prospective interventional trial. SETTING: Outpatient anticoagulation clinic. PATIENTS: Patients who required reversal of their normal or excessive therapy with oral anticoagulant drugs were recruited. INTERVENTIONS: All patients received a single oral dose of vitamin K1. The dose was calculated using a regression formula and was intended to decrease the international normalized ratio (INR) to a predetermined value. Patient follow-up continued for 8 weeks. We compared the actual change of the INR to the predicted change. RESULTS: Sixty-five reversals of anticoagulant therapy were initiated in the study group. Sixty-four of the 65 reversals were successful. The mean (+/-SEM) initial INR was 2.6+/-0.1 for the preprocedure patients and 8.4+/-0.5 for the excessively anticoagulated patients. The predicted change in the INR correlated with the actual change (r = 0.92, p < 0.0001). There were no thromboembolic events and only one hemorrhagic complication. The mean (+/-SEM) dose of oral vitamin K1 was 5.0+/-0.3 mg for the preprocedure patients and 10.0+/-1.0 mg for the excessively anticoagulated patients. CONCLUSIONS: The administration of a single oral dose of vitamin K1 is a safe and effective method for partially reversing anticoagulant therapy without disrupting the daily maintenance dose of warfarin. A reliable regression formula was developed to predict the dose of vitamin K1 needed to achieve the desired INR.

Group I: choosing the appropriate method of placement of an enteral feeding tube in the high-risk population.

The traditional nasogastric/nasoenteric feeding tube is the preferred access device for short-term feeding (< 30 days), with delivery into the stomach suggested unless aspiration or motility abnormalities are present. Preference for a long-term access device is operator- and facility-dependent. Endoscopic or fluoroscopic placement is preferred as first choices over laparoscopic placement because of considerations of cost, need for general anesthesia, and need for operating room time. Gastrostomy is preferred over intestinal placement for long-term access unless problems with aspiration or motility abnormalities exist.

Complications of long arm-catheters: a randomized trial of central vs peripheral tip location.

BACKGROUND: This two-part study initially evaluated complications associated with catheters inserted via upper extremity veins. The second prospective phase compared thrombotic risk of peripheral catheter tips vs a central vein terminus. METHODS: Patients from public institutions with infectious diseases were observed throughout their inpatient and outpatient use of IV catheters. Seventy-two and 39 patients enrolled in phase 1 and phase 2, respectively. Phase 1 consisted of prospective observations and analysis of complications and associated risk factors. Phase 2 randomized patients to a catheter tip location in the superior vena cava or the axillosubclavian-innominate vein and compared the incidence of thrombosis, phlebitis, and infection. RESULTS: In phase 1, there was an increased risk of thrombosis with peripheral tip localization (61% vs 16%, p < .05). Phase 2 confirmed increased thrombosis with tips in the axillosubclavian-innominate vein compared with the superior vena cava (60% vs 21%, p < .05) with an improved survival for central tip catheters (p < .02). Catheters associated with thrombosis were more likely to become infected (r = 0.48, p < .02). CONCLUSIONS: The experience supports use of the long arm catheter as an effective device for parenteral therapy. A novel method for placing these catheters makes most patients candidates for this approach. Placing a long arm-catheter's tip in the central venous circulation reduces the risk of thrombosis. A high incidence of tip misdirection indicates a need for radiographic confirmation before use.

Accelerated improvement of alcoholic liver disease with enteral nutrition.

This prospective study compared the effects of tube-fed nutrition with those of a regular diet in alcoholic liver disease. The high prevalence of malnutrition in patients with alcoholic liver disease requires clarification of the benefits of aggressive nutritional support. Patients were randomly assigned a regular diet without or with tube-fed supplementation, delivering 1.5 g/kg protein and 167 kJ/kg daily. Comparisons of encephalopathy, antipyrine clearance, metabolic rate, and biochemical parameters were performed weekly for 4 weeks. Sixteen patients receiving enteral supplementation had antipyrine half-life (50% vs. 3% reduction), serum bilirubin (25% vs. 0% reduction), and median encephalopathy scores that improved more rapidly than those of controls. Initially, 15 controls did not consume adequate calories to meet measured resting energy expenditure. Aggressive nutritional intervention accelerated improvement in alcoholic liver disease. Adverse effects did not offset the demonstrated benefits of a 2-cal/mL, casein-based tube-fed supplement. These findings support the use of standard, casein-based solutions in the treatment of alcoholic liver disease and as the control condition for future studies.

Nutritional and metabolic response to acute spinal-cord injury.

The metabolic response to complete spinal cord injury was prospectively studied in 10 patients with Frankel class A spinal cord injury. Weekly excretory and balance studies profile the changes in nitrogen, calcium, and 3-methylhistidine excretion in relation to body weight and metabolic rate. The initial resting energy expenditures were 10% below what was predicted, and body weight decreased by 10%. Nitrogen excretion paralleled the changes in body weight. Calcium excretion increased for 3 weeks and reached a plateau 150% above baseline. Our results chronicle the magnitude of metabolic response to spinal shock. Comparison with reported values shows this response exceeds that seen in immobilized patients. Nitrogen excretion rose to levels seen in highly stressed patients and must be considered in the management of patients with acute spinal-cord injury.

Streptococcus bovis catheter infection and the short bowel syndrome.

Streptococcus bovis bacteremia has been associated with several gastrointestinal disorders, most notably carcinoma of the colon. This report describes a 57-year-old woman with short bowel syndrome in whom S. bovis bacteremia and an infection of an indwelling parenteral nutrition catheter developed. A barium enema revealed diverticula and a foreshortened small intestine. This case implicates the short bowel syndrome in the pathogenesis of S. bovis bacteremia and supports empiric antibiotic coverage for both skin flora and enteric pathogens in patients with Hickman catheter sepsis and known gastrointestinal pathologic conditions.

Bioavailability of warfarin in a patient with severe short bowel syndrome.

Acquired warfarin resistance has resulted from altered drug metabolism and excessive vitamin K. A third possible mechanism, decreased gastrointestinal absorption of the drug, was examined in a patient with short bowel syndrome and severe malabsorption who demonstrated transient warfarin resistance. Despite the resistance, bioavailability studies demonstrated normal drug absorption and a prolonged half-life. The parenteral administration of vitamin K proved to be the cause of the prolonged warfarin resistance.

Hepatorenal syndrome managed with hemodialysis, then reversed by peritoneovenous shunting.

A patient with acute decompensated chronic liver disease developed acute tubular necrosis after an episode of hypotension. Renal failure was managed by hemodialysis for 11 weeks during which period hepatic function improved. Despite persistently severe oliguria, tubular function recovered as judged by a fall in urine sodium content and a rise in specific gravity, suggesting the development of the hepato-renal syndrome. Therefore, a peritoneovenous shunt was inserted. This was followed by a prompt diuresis; further dialysis was not required. This case suggests potential roles for hemodialysis and peritoneovenous shunting in patients with advanced, but potentially reversible hepatic and renal failure and draws attention to the need for formal evaluation of such a possibility.