We recently learned about the unfortunate death of a patient whose IV tubing had been connected to his tracheostomy tube cuff inflation port. The patient had both a Shiley low-pressure tracheostomy tube and a triple lumen central IV line catheter in place. Someone accidentally attached an IV fluid line to the tracheostomy cuff pilot line (used to inflate the balloon and regulate pressure), instead of the intended port on the triple lumen catheter. Once the IV infusion pump was turned on, the cuff continued to inflate with fluid causing the tracheostomy tube to become obstructed. A roommate called a nurse to alert her to the patient’s respiratory distress, but the patient eventually arrested. The obstruction was noticed when the code team was unable to inflate the lungs. The line was disconnected and fluid and air were removed from the cuff, but the patient did not survive.
It may be hard to understand how one could mistake a tracheostomy cuff tube for a triple lumen catheter, but several underlying factors allowed this error to happen. The patient had just been transferred from critical care to a medical unit where tracheostomy tubes were infrequently encountered and patients were not routinely monitored with pulse oximetry or capnography to quickly detect problems. Dim lighting also played a role. It is likely that the infusion was connected without additional light to avoid waking the patient or his roommate. The risk of error was heightened because the patient’s triple lumen catheter was not secured, so the tubing hung down at the same level as the tracheostomy cuff tubing. Although the size of the tracheostomy pilot line is distinctly thinner than regular IV tubing, triple lumen lines also are thin. Furthermore, the connection ports on needleless tubing can appear very similar to the tracheostomy pilot line—an interesting example of how an apparent “win-win” safety innovation (a needleless system) can lead to new, unsuspected problems.
It is also important to mention that the IV tubing fit into the pilot line. The port on the pilot line is compatible with slip tip and Luer lock syringes (and therefore IV tubing) for easy inflation or deflation. Because high-volume, low-pressure cuffs are used to lower the long-term risk of tracheal injury, they are compliant enough to accept a massive volume of air—or fluid in this case. Unfortunately, the infusion pump provided sufficient pressure to overinflate the cuff, but it did not alarm or stop.
We have received a similar report of accidental injection of drugs into an endotracheal tube cuff during resuscitation efforts. We have also heard of other unusual cases such as attaching oxygen to a total joint drainage system, which resulted in a patient’s death from a gas embolism. These rare occurrences are not easily prevented by simply encouraging staff to be careful. They are symptomatic of a larger class of errors that we’ve heard labeled as, “Wrong tube, wrong hole, wrong connector.” When viewed in this light, there’s much that should be done to prevent this type of error. Healthcare providers should:
- Identify error potential through failure mode and effects analysis when introducing new tubes, catheters, and connectors into a healthcare system.
- Provide training to nurses, pharmacists, physicians, and respiratory therapists before using new tubes, catheters, and connectors. Include discussion about possible sources of error identified during failure mode and effects analysis and steps to avoid these errors.
- Affix labels on lines near insertion sites when the patient has more than one potential connection to a port of entry into the body (IV, arterial, umbilical, enteral, bladder, tracheostomy, drainage tubes, etc.).
- Trace all lines from the source (and infusion pump if used) to the connection port to verify attachments before administration of drugs, solutions, or other products.
- Independently double-check all line attachments with two practitioners if infusing high alert medications or solutions, or if administering products to high-risk patient populations.
- Monitor patients (e.g., vital signs, frequent observation, pulse oximetry, capnography, cardiac monitoring, etc.) appropriately to assess the effects of medications, detect an error quickly, and minimize the consequences of an error.
Healthcare regulators and manufacturers also must play a role in solving this problem. Standard-setting groups must gain consensus on issues surrounding Luer lock connectors. Although careful testing of possible new error pathways is necessary, manufacturers must find ways to make problematic connectors incompatible with each other. Some testing and redesign of IV infusion pumps might be in order so that a high-pressure alarm would alert staff if a similar incident happened. The FDA must also take action. Perhaps tracheostomy tube manufacturers should be required to adopt a universal method of differentiating cuff inflation ports (to look/feel different) from IV ports, especially since compatibility with existing syringes is necessary for safe use. Practitioners can help spur action by reporting events to the USP-ISMP Medication Errors Reporting Program (800-233-7767 or www.ismp.org). Experience has shown that the more evidence we have to show manufacturers, the greater the likelihood of design changes.
Dr. Cohen and Ms. Smetzer are with the Institute for Safe Medication Practices, 1800 Byberry Rd, Suite 810, Huntingdon Valley, Pennsylvania, www.ismp.org.
Editor’s Note: We duplicated this scenario by attaching a tracheostomy pilot balloon connector to a typical infusion pump equipped with a syringe containing saline. The pump continued to operate, filling the cuff to approximately a 70 cc volume before the tracheostomy cuff ruptured.