feb_march05.html

University of Virginia Nutrition E-Journal Club
February/March 2005

We have combined the February and March E-Journal Club reports, so our introduction will be brief.  We hosted three trainees in March, who hailed from Cincinnati, Chicago, and Newport News.  The picture below is from rounds with the Surgical Nutrition Support Team.

 

In February we reviewed an article from the European Journal of Clinical Nutrition and in March we discussed an article from Critical Care Medicine.

February Citation: 

Luis DA, Izaola O, Cuellar L, et al.  Randomized clinical trial with an enteral arginine-enhanced formula in early postsurgical head and neck cancer patients.   Eur J Clin Nutr 2004;58:1505-1508.

Study Question:

Does an arginine-enhanced enteral feeding improve nutritional variables and outcome (systemic infection, fistula occurrence, wound infection, length of stay) compared with an isonitrogenous, isocaloric enteral feeding in a population of postoperative head and neck cancer patients.

Summary: 

Prospective, randomized trial of 90 head and neck cancer patients who received enteral feeding postoperatively for at least 10 days.  Patients actually received an average of 21 days of enteral nutrition.  The enteral feedings were similar in macronutrient content with the exception of supplemental arginine in the experimental formula.  No breakdown of the micronutrient content of the formulas was included.  “Nutritional parameters” that were measured included albumin, prealbumin, transferrin, lymphocytes, and weight.

Results:

There were no significant differences in nutrition parameters, systemic infection (pneumonia or UTI), or wound infection between the two groups.  The researches reported that the arginine-supplemented group had significantly less fistula development postoperatively (5% versus 11%, p = < 0.05) and a significantly decreased length of stay (25.8 +/- 15 versus 35 +/- 24 days, p= < 0.05) compared to the control group.  The arginine-supplemented group had a significantly greater incidence of diarrhea compared to the control group (40% versus 13% in control, p = < 0.05).

Evaluation:

This is an interesting study, but it does have several limitations.  One obvious consideration is that it is not a double-blind study, which is especially important whenever outcomes may be influenced by subjective assessment (length of stay).  In addition, although the percent of patients with fistula development was statistically different (5% vs 11%), when you look at the actual numerical difference of patients with fistula development it is 2 patients in the arginine-supplemented and 5 patients in the control group.  Our concern was that in relatively small groups this type of difference could be due to random chance. 

Some other observations were that there was no mention of possible differences in micronutrient content of the two formulas – it would be valuable to know if these formulas had a similar content of vitamin C, vitamin A, and zinc for instance.  There is also no mention of the actual amount of formula that was received by the patients (a factor that can vary in any enterally fed population) and if this was similar between the two groups.

Take home message: 

This is an intriguing study, but it should be repeated in a larger population, and in a double-blind protocol before we can advocate routine use of specialty products in this population.

March Citation:

McClave SA, Lukan JK, Stefater JA, et al.  Poor validity of residual volumes as a marker for risk of aspiration in critically ill patients.  Crit Care Med 2005;33:(2):324-330.

Study Question

  1. Whether residual volume (RV) accurately predicts the risk for aspiration.
  2. The most appropriate designated level of RV at which ETF should be withheld, and
  3. To determine whether certain clinical factors and physical findings correlate with aspiration risk.

Summary: 

  • Medical, coronary, or surgical critically ill patients > 18 yrs of age requiring mechanical ventilation were fed via 8 or 12 Fr NG or PEG.  Patients were randomized to one of two groups:
    • Study group, feedings were withheld for RV > 400 mL
    • Control group, feedings were withheld for RV > 200 mL
  • Patients were rechecked every 2 hrs thereafter.  Throughout the 3 days of the study (and then following peripherally until discharged from the ICU), patients were evaluated for the development of nosocomial aspiration pneumonia. 
  • Goal TF was based on either measured REE or 25 kcal/kg. 
  • An aspiration risk score and a bowel function score were calculated for each pt
  • Daily percent of calories provided/required was calculated
  • Yellow microscopic colorimetric microspheres and 4.5 mL of blue food coloring were added to the feeding.
  • Bedside evaluations were performed every 4 hrs throughout the 3 days of the study to measure:
    • RV
    • Check patient position
    • Collect secretions from the oropharynx and trachea.
  • All samples were visually inspected for the presence of blue food coloring.

Results:

  • 1,118 total samples obtained (531 oral, 587 tracheal).  Mean frequency of regurgitation per patient was 31.3%.  Mean RV for all regurgitation events of 35.1 mL (0–700 mL). 
  • Blue food coloring was detected on only three of the 1,118 (0.27%) samples.
  • RV was <50 mL on 84.1% and > 400 mL on 1.4% of bedside evaluations.
  • Low RV did not assure the absence of events, because the frequency of aspiration was 23.0% when RV was <150 mL.
  • Raising the designated RV for cessation of enteral tube feeding from 200 mL to 400 mL did not increase the risk, because the frequency of aspiration was no different between controls (21.6%) and study patients (22.6%).
  • The frequency of regurgitation was significantly less for patients with PEGs compared with those with NG tubes (20.3% vs. 40.7%, respectively).
  • There was no correlation between the incidence of pneumonia and the frequency of regurgitation or aspiration.

Evaluation:

The impact of this study is limited by the small number of participants (only 40 overall) and the fact that 19 patients were fed via PEG while 21 were fed via NG.  It is important to note that patients who had a PEG had significantly less regurgitation, and a trend towards less aspiration (18.4% vs 27.6%) so the effect of any possible difference between the two residual protocols could be obscured by the different type of  feeding tube.  The details of the patients are not provided in the study, and any possible uneven distribution between the two groups in terms of age, diagnosis, or type of feeding tube is unknown.  In the setting of small groups, different feeding methods, such a small number of residual checks over 400 mL (1.4%), and > 84% of all residual checks were less than 50 mL, the group did not feel that this study provided adequate evidence to justify raising the threshold for a residual “cut-off” to 400 mL.  The study does confirm that blue food color is not a valid marker for aspiration.

Other News:

  • The UVAHS Tyco Kendall Healthcare Nutrition Support Traineeship Scholarship is now available!  There was a technical problem with the website survey process in the first weeks; if you know anyone who had filled out a survey via the link below, PLEASE ask them to go to their website and fill out another before April 15, 2005 so we can be sure they are in the drawing.
  • Here is the link:
    http://www.healthsystem.virginia.edudh/traineeship.html
  • Check out the latest Practical Gastroenterology articles available at:http://www.healthsystem.virginia.edu/pub/digestive-health/nutrition.html
    • Jeejeebhoy KN.   Management of PN-induced Cholestasis. Practical Gastroenterology  2005; XXIX(2):62.
    • Fessler TA.  Trace Element Monitoring and Therapy For Adult Patients Receiving Long Term Total Parenteral Nutrition.  Practical Gastroenterology  2005; XXIX(3):44.

  • There is a job opening at UVA Health System for a Neonatal Dietitian. See below for details:

    The University of Virginia Health System, a progressive medical center located in historic Charlottesville, is seeking a full-time RD for the NICU and the transitional nursery. A minimum of 3 years pediatric experience is required and a Masters degree and CNSD or CSP is preferred. Responsibilities will include providing medical nutrition therapy to high risk neonates including entering of enteral and parenteral nutrition regimens using the medical information system, education of patients and families in the outpatient setting, education of NICU healthcare staff and active participation in hospital QI committees. Position offers a competitive salary and excellent benefits. For more information contact Lynda Fanning at (434) 982-2522 or e-mail her at lef5h@virginia.edu. Please send resume’ and cover letter to: Lynda Fanning, MPH, RD, University of Virginia Health System, Dept. of Nutrition Services, Box 800673, Charlottesville, VA 22908.

  • We have been informed by one of our former team members (Emily Gasser – who is now part of their service) that there is a nutrition support job opportunity available at the Cleveland Clinic.  Here are the particulars:

    Metabolic Support Clinician
    Manage all facets of administering total parenteral nutrition (TPN) to Cleveland Clinic Foundation (CCF) adult patients.  CNSD certification must be obtained within 1 year from date of hire. Three or more years of experience in nutrition support is strongly preferred.  Contact: Cindy Roth rothc@ccf.org

  • Humor Carol – this is one of her favorites when Spring rolls around…

    Daffodils
    By:William Wordsworth

    Daffodils
    I Wander’d lonely as a Cloud
    That floats on high o’er Vales and Hills,
    When all at once I saw a crowd,
    A host, of golden Daffodils,
    Beside the Lake, beneath the trees,
    Fluttering and dancing in the breeze.
    Continuous as the stars that shine
    And twinkle on the Milky Way,
    They stretch’d in never-ending line,
    Along the margin of a bay:
    Ten thousand saw I at a glance,
    Tossing their heads in sprightly dance.
    The waves beside them danced, but they
    Outdid the sparkling waves in glee:--
    A poet could not but be gay
    In such a jocund company:
    I gazed—and gazed—but little thought
    What wealth the show to me had brought:
    For oft, when on my couch I lie
    In vacant or in pensive mood,
    They flash upon that inward eye,
    Which is the bliss of solitude,
    And then my heart with pleasure fills,
    And dances with the Daffodils.

Joe Krenitsky MS, RD
Carol Parrish RD, MS

PS – Please feel free to send this on to friends and colleagues.