You are resuscitating a hypotensive patient with severe sepsis and have just hung your 4th liter of crystalloid. On the fluid bags, you wrote the numbers 1 through 4 in permanent marker to help keep track of your resuscitation. As you finish placing your central line the charge nurse enters the room. He informs you that according to the Institute for Safe Medical Practices (ISMP), writing directly on IV bags with permanent marker is not recommended due to concerns that the ink will leach into the bag and potentially cause harm to your patient.1–4
This situation raises several questions:
- Should we write on IV bags in permanent marker?
- Is there a possibility of ink diffusing through polyvinylchloride (PVC) bags?
- If so, is there potential harm to the patient?
These are valid questions, but unfortunately the answers may be unclear, contradictory, or even non-existent. Are there theoretical concerns with writing on IV preparations? What do the manufacturers say?
According to IV bag manufacturers Baxter, Hospira, and B Braun the absence of ink leaching from permanent markers cannot be guaranteed and writing on bags with permanent marker is not recommended, especially since there are many different ink, marker, and pen manufacturers with varying types and styles of ink.5–9
If we cannot get a definitive answer from the manufacturers, let’s take a look at some literature that has attempted to identify possible ink contamination in IV bags. A PubMed search was done with search criteria including “PVC and ink”, “IV bag and ink”, “IV bag and marker”, “PVC and marker”, “ink and leaching”.
Gas chromatography was used to detect ink solvents from a Markette No. 590 felt-tip marker. A Baxter ViaflexTM IV bag completely covered with ink was compared to a control Baxter ViaflexTM IV bag without ink. The ink was in contact with the bag for 30 minutes before samples were drawn. The results from the gas chromatography showed no significant difference in the marked bag compared to the control bag. This study was designed to detect the volatile solvents in the marker and not all components of the ink. However, this study only looked at one type of PVC bag, fluid, and marker.
Story and colleagues had previously found biologically active contaminants in PVC bags containing 0.9% sodium chloride. In this study they wanted to determine if the contaminants varied by manufactured country of origin. They tested manufacture printed vs. non-printed bags for contaminants using high-resolution capillary gas chromatography-mass spectrometry. The authors concluded that printing ink on the bags was most likely the source of t-butyl cyclohexanol and t-butyl cyclohexanone contamination. The potential health concerns of these contaminants are unclear.
Multiple IV bag brands were studied including Baxter polyvinyl chloride laminate #146, Hospira VisIV® and Freeflex®, B. Braun Excel® system, Baxters’s VIAFLEX® and VIAFLEX.Plus® via visible and ultraviolet spectrophotometric scans. The solutions in the bags included 0.9% sodium chloride, Lactated Ringers, dobutamine in 5% dextrose, 6% hetastarch in 0.9% sodium chloride, and Plasma-Lyte A®. The manufacturer of Sharpie® provided the known wavelengths to detect black ink used in their products. Filter paper was inserted into empty Sharpie® marked bags and placed under approximately 20 pounds of pressure. The filter paper was visually inspected after a 24-hour time period to identify possible bag leaching from a fine-tip Sharpie®. The results of this study showed no visible or spectrophotometric evidence of leaching. Other components of Sharpie® ink, such as solvents, were not specifically tested. The authors also demonstrated that silk surgical tape is permeable to Sharpie® pens.
Eight Baxter PVC bags were divided into two groups — one group was marked with a 3×3 inch square using a soft-tip Sharpie® and the other group was used as a control. The bags were kept at room temperature for the duration of the study. They then employed gas chromatography/mass spectrophotometer with samples tested at 6, 12, and 24 hours. There were no ink molecules detected at any time. Additionally samples were cultured to evaluate possible microbial contaminates and all samples had no growth.
The methods used to test for potential contamination vary greatly. Mass spectroscopy is commonly used to detect ink whereas the volatile components, such as solvents, are best detected using gas chromatography. In addition, Story and colleagues point out that additional contaminants may be detected depending on the specific ink selected.
According to Sharpie® permanent fine point marker material safety data sheet (most commonly used marker at our institution) the ink can be an irritant and is the only side effect listed.12
With no definitive information from the manufacturers and limited literature on bag leaching, what are the answers to our earlier questions?
The ISMP recommends the use of labels that have appropriate information written on them. Implementing strategies such as standardized labels with required fields in all patient rooms for emergent situations could be beneficial. In the absence of labels, during emergent situations such as the resuscitation of a hypotensive patient, writing directly on the bags could be the best way to satisfy ISMP’s recommendation and preventing errors. Although there are many different manufacturers of both pens and bags which make extrapolation of data for all combinations difficult, there is limited evidence of ink leaching and no evidence to this date of patient harm from this practice. If the contents of the bags are infused within 30 minutes of writing, the possibility of leaching is not likely. One additional strategy would be to write near the top of the bag where there is less potential exposure to the contents of the bag.
This is an interesting topic without a lot of data either way. This information will be helpful for those who utilize the marker technique to keep track of fluid volume during resuscitations. I have a few comments to help streamline the information for the readers of ALiEM:
- Do you have a link to the ISMP report that the charge nurse cites in the clinical scenario? If so, please include it. If it doesn\'t exist, it would be good to make that point to close the loop.
- What was the search strategy to ensure no articles were missed? The bigger question is if infused ink is a problem. Are there any data on that?
- Given that many are choosing to use LR or Plasma-Lyte in place of large volumes of sodium chloride 0.9%, it would be good to comment if these other solutions also primarily come in PVC bags. Also, please include which fluids were used in each of the studies.
- Since not all of the readers will be familiar with gas chromatography\'s role in this type of testing, I recommend expanding on the methods for the Bickler study. Is what they did a good model for clinical practice? What specifically were they looking for with GC? Is GC the correct test to say whether or not there was any leaching?
- Similarly, for the Langston study, please discuss the testing techniques in more detail. How exactly was the filter paper used as the surrogate for leaching.
- Same comment about the Clark study, please include more methodology information. Are the tests used accurate in picking up small quantities of ink?
- Since resuscitations are fraught with errors (Resuscitation 2012;83(4):482-7), I recommend a strong conclusion to follow appropriate labeling practices whenever necessary. Also, you might offer alternatives for those uncomfortable with the possibility of leaching ink (however small the risk), such as writing the bag number on medical tape and placing it on the bag or the tubing.
Great topic! I\'ve never considered this as a potential problem...
Re: question 3: The potential harm to the patient is not well described. Despite the lack of convincing evidence either way, as a practicing clinician, I\'d like to know the potential risks so I can make my own decisions regarding risk/benefits for my patients. Please expand on the potential risks to the patient.
Re: Dr Hayes: question #4- What are the potential toxins not assessed by GC?
In general, I agree with the prior reviewers that expanding on the methodology in each of the cited references would be beneficial to the reader.
Thank you for your interesting post!
Expert Peer Review
The practice of writing on IV fluids has been discouraged for many years due to the fear of ink and other solvents leaching, contaminating the fluid, and potentially harming the patient. It is well documented that errors occur when products are not labeled appropriately. In order to eliminate the practice of writing on bags when labels are not available, evidence must demonstrate that leaching occurs and describe the potential harm to the patient as the risks associated with not labeling are well understood among health care professionals.
Binkler 1989 should be changed to Bickler 1989. Although the study checked for leaching at only one time point of 30 minutes, the surface area of the bag covered with marker is substantially greater than that which would be found in clinical practice. Gas chromatography was used to demonstrate that several solvents did not penetrate the IV bag and contaminate the 0.9% sodium chloride. Include the limitations of the study such as the testing was conducted at one time point, with one type of PVC bag, fluid, and marker.
Story and colleagues refers to biologically active contaminants in PVC bags containing 0.9% sodium chloride. It would be helpful to understand why they consider the contaminants biologically active. In addition, it must be clear to the reader that the contaminants were likely from the ink used by the manufacturer to print on the bag. This study did not evaluate writing on IV bags with markers.
It is important to mention that Langston and colleagues conducted a recent study to determine if the black ink of a permanent Sharpie® felt tipped fine point marker could leach from five different types of the IV bags available on the market today and contaminate a variety of solutions. Recommend mentioning that the IV bags on the market today differ from those tested in 1989 by Bickler. Provide the names of the five different bag types tested so that reader will have enough information to determine if the
conclusion applies to their practice setting. “The manufacture of Sharpie®” needs to be changed to “The manufacturer of Sharpie®.” Expand on the methods used in this study. Include information on the strengths of this study such as the variety of bag types, solutions, marker lot numbers, time points, and methods used.
With the Clark study, expand on the methodology, limitations, and strengths.
The conclusion and answers to earlier questions are a bit repetitive consider combining.
ISMP recommends the use of labels that have appropriate information written on them and employing strategies to stock blank labels in all patient rooms for emergent situations would be helpful. Although this evaluation was conducted with fluid resuscitation in mind, we should anticipate that the information will be used in other clinical scenarios. Therefore, it would be beneficial to have labels available that include appropriate prompts (patient name, drug name, dose, date, time, etc.) so that the handwritten labels are complete and the labeling practice is standardized.
In the absence of labels, writing directly on the bag with a permanent marker is best way to label the intravenous fluid, satisfy the ISMP recommendation, and prevent errors. Although there are many different manufacturers of both pens and bags which makes extrapolation of the data for all combinations difficult, there is limited evidence of ink leaching and less evidence of patient harm from this practice. If clinical risks have been identified, please include supporting information or state that clinical risks have not been identified. In the event that the bag will hang for more than 30 minutes, it could be suggested that the writing should be near the top of the bag (where the bag is hung) to limit the contact time of the fluid with the part of the bag that has been written on.