Answering your questions

Nov. 20, 2014

Q

Is it appropriate/legal to have plants in the clinical laboratory? Our lab manager requested the removal of our plants a number of years ago, as an “infection control” issue. I inquired during both a New York State Department of Health and JCAHO inspection if there is documentation to support the “infection control” claim. Both surveyors expressed that this was not a policy known to them. Our manager is now retired and we would like to bring plants back into our work area, if appropriate. I would like to know if there is any rule, law, or policy anywhere that addresses this issue.

A

Hospitals often have rules that may limit or prohibit the placement of flowers and/or plants in certain patient-care areas. Studies have shown that bacteria, such as Aspergillus spp., or fungi (Fusarium spp.) may be sources of infection, especially with immunocompromised patients. Fresh flower vase water can also breed significant levels of bacteria. However, in most cases, the difference in the level of aerosol contamination was no different than that found in homes or restaurants. In light of all this, the CDC recommends that flowers and plants should be restricted from patient-care areas where immunocompromised patients are located.1,2

I am not aware of any regulatory guideline that specifically prohibits having plants in a clinical laboratory area, as was confirmed by the New York Department of Health and the Joint Commission inspectors. However, it may be prudent to limit placement of plants and flowers to those areas of the lab where there would be little or no opportunity for specimen contamination. I would think microbiology lab areas and areas where DNA technology is used would be of particular concern. 

References

  1. Practices Advisory Committee (HICPAC), U.S. Department of Health and Human Services, Centers for Disease Control and Prevention (CDC). Guidelines for Environmental Infection Control in Health-Care Facilities. Recommendations of CDC and the Healthcare Infection Control. Atlanta, GA. 2003. www.cdc.gov/hicpac/pdf/guidelines/eic_in_HCF_03.pdf. Accessed October 8, 2014.
  2. World Health Organization. Practical guidelines for infection control in health care facilities. SEARO Regional Publication No. 41. 2004. http://www.wpro.who.int/publications/docs/practical_guidelines_infection_control.pdf. Accessed October 8, 2014.

Q

When placing pipettes in a pipette washer/dryer, should the tips be up or down?

A

Interestingly, some pipette washing protocols suggest placing the pipette tips down,1-5 while others suggest tips up.6-8 In reviewing these protocols, no explanation is offered in support of preference position and its potential efficacy in cleaning pipettes. 

However, it would seem that the interior of the tip, being of smaller dimension than the rest of the pipette, would be the most difficult area to clean. In following this logic, the pipette should be placed in such a position as to maximize the amount of wash solution passing through it. Thus, completely submerging a pipette (in a pre-soak bucket) with the tip up and the larger bore of the pipette facing down would appear to provide greater internal access to the cleaning fluid when placed in the bucket. 

Likewise, when placed in an automatic washer with the jet stream above the pipette, tips should be facing down, thus again making the larger opening of the pipette more accessible. In addition, the jetted wash fluid streaming through the pipette from a larger opening to a smaller one (similar to a garden hose) would place greater force on the fluid at the tip, thus ensuring maximum cleansing pressure.

References

  1. Bellco. Cleaning of pipettes. http://www.bellcoglass.com/sites/default/files/kcfinder/files/Cleaning%20Glass%20Pipettes.pdf. Accessed October 8, 2014.
  2. Sigma-Aldrich. Suggestive cleaning of glassware. https://www.sigmaaldrich.com/content/dam/sigma-aldrich/docs/Aldrich/Bulletin/al_techbull_al228.pdf. Accessed October 8, 2014.
  3. Miele. Effective cleaning of pipettes. www.labmanager.com/news/2012/12/effective-cleaning-of-pipettes?fw1pk=2#.U7AIM7EcwvA. Accessed October 8, 2014.
  4. Corning. Care and safe handling of laboratory glassware. http://osum.ucr.ac.cr/sites/default/files/documentos/CUIDADO%20Y%20SEGURIDAD%20PARA%20MANEJO%20%20DE%20CRISTALERIA.pdf .Accessed October 8, 2014.
  5. Gate I. Caring and cleaning lab glassware. June 2011. http://labprotocolsonline.blogspot.com/2011/06/caring-and-cleaning-lab-glassware.html. Accessed October 8, 2014.
  6. United Clinical Laboratories, Iowa. http://webserver.pa-ucl.com/wwwdocs/instrv/MFV.htm. Accessed October 8, 2014.
  7. UCLA. Pipette washing instructions. http://www.chem.ucla.edu/dept/Faculty/merchant/pdf/Pipettewashinginstructions.pdf. Accessed October 8, 2014.
  8. Exova. Glassware cleaning. SOP No. 2800, Rev6.   http://www.wcaslab.com/qa/sop/2800v6%20-%20Glassware%20Cleaning.pdf. Accessed October 8, 2014.

Q

Is it more acceptable to perform a Free T3 rather than a Total T3?

A

Approximately 12% of the U.S. population will develop a thyroid problem within their lifetime.1 Subsequently, thyroid testing has become prevalent among many practices, from pediatrics, to OB-GYN, to cardiology.2 Patients suspected of a thyroid problem are often tested for changes in TSH (thyroid stimulating hormone) and/or FT4 (free thyroxine). If the result is  abnormal, a total T3 (triidothyronine) or FT3 (free T3) may be ordered. 

One of the first tests that may be ordered is a TSH, and if it is elevated that would suggest hypothyroidism, while a low TSH would suggest hyperthyroidism. Conversely, an elevated T3 or T4 would be more consistent with hyperthyroidism and a low T3 or T4 with hypothyroidism. Decreased levels for all three analytes are not uncommon in hospitalized patients.3

Approximately 99.7% of T3 is bound to protein (TBG; thyroxine-binding globulin), with the remaining circulating as free T3.3 However, abnormal protein levels or protein binding capabilities may interfere with the total T3. In addition, certain medications, such as aspirin or birth control pills, may affect total T3 results, but have less of an impact on FT3.3 Therefore, measuring FT3 in patients with abnormal TBG levels, hypoalbuminemia, or other abnormal thyroid-binding proteins may be a better choice than just a total T3.4,5 The final decision in selecting appropriate testing should rest with the pathologist and the ordering healthcare provider, who has a more detailed patient history.

References

  1. American Thyroid Association. http://www.thyroid.org/media-main/about-hypothyroidism/. Accessed October 8, 2014.
  2. Cooper DS, Ladenson PW. Chapter 7. The Thyroid Gland. In: Gardner DG, Shoback D. eds. Greenspan’s Basic & Clinical Endocrinology, 9e. New York, NY: McGraw-Hill; 2011.
  3. T3. www.labtestsonline.org. Accessed October 8, 2014.
  4. Aziz DC. Thyroid disorders, in Use and Interpretation of Tests in Endocrinology. Chapter 12, pp139-155 (1997).
  5. Woliner K. The Free T3 (FT3) Test. Understanding Thyroid Lab Tests. http://thyroid.about.com/cs/testsforthyroid/a/freet3.htm. Accessed October 8, 2014.