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We’ve previously discussed cases of dialysis patients suffering massive blood loss after their dialysis catheters became dislodged (see our Patient Safety Tips of the Week for March 26, 2007 “Alarms Should Point to the Problem” and April 25, 2017 “Dialysis and Alarm Fatigue”).
Last year, The Renal Association (UK) was made aware of three cases over a period of several months of disconnections during hemodialysis treatment with consequent significant blood loss and/or suspected air embolism (The Renal Association 2018a).
We first discussed a dialysis catheter disconnection incident in our March 26, 2007 Patient Safety Tip of the Week “Alarms Should Point to the Problem”. An ESRD patient was having his regularly scheduled dialysis session. Since he would be in the dialysis center for several hours, he was in a comfortable lounge chair that tipped back. Also, since it was somewhat cool, he was offered a blanket to keep warm. Midway through the dialysis session, the low-pressure alarm rang. The nurse turned off the alarm and eyeballed the patient and saw no blood. Nothing further was done. Soon thereafter the low pressure alarm triggered again. This time it was recognized that the dialysis catheter had become dislodged and the patient had, in fact, had considerable blood loss. It had not been appreciated immediately because the blanket had been covering up the catheter site and the blood, rather than being visible on the floor, had been pooling in the webbing of the lounge chair.
The thrust of our March 26, 2007 Patient Safety Tip of the Week “Alarms Should Point to the Problem” was that alarm system setups should focus visual attention to that part of the system where the problem originates. Anyone who has ever spent time in an ICU or other high tech medical environment knows that the usual first response to an alarm is to turn the alarm off. Proper design of medical equipment therefore should force the responder to focus on the source of the problem. In the case at hand, the equipment and alarm were on the side of the patient opposite from the involved limb so that the visual attention of the responder was not directed immediately to the site the alarm was drawing attention to.
A second consideration is the complexity of the alarm screen. That complexity may lead to responders simply taking the easy way out and clearing the alarm, particularly if they anticipate the alarm will be re-triggered if something serious is really going on. The most reliable patient safety interventions are forcing functions. We’ve, therefore, suggested that these alarm systems program in a “hard” stop for this particular alarm that requires the responder to verify that he/she has inspected the access site. That verification should then become part of the medical record.
In our April 25, 2017 Patient Safety Tip of the Week “Dialysis and Alarm Fatigue” we discussed a case with striking similarities to that in our previous column (CDPH 2017). A patient admitted with an MI suffered deterioration of his chronic renal disease and was begun on continuous renal replacement therapy (CRRT) with a femoral catheter for dialysis access (technically, it was continuous veno-venous hemofiltration or CVVH). For comfort, the patient was covered with a blanket, which obscured the catheter access site. Unfortunately, at some point the return line became loose and disconnected from the femoral catheter which caused massive blood loss and cardiac arrest. He received CPR and blood transfusions and was resuscitated but died several days later. That case had a cascade of errors that all contributed to the fatal incident (see the prior column for details) but, once again, failure to heed the alarm was a major one.
In both the cases described in our prior columns, blankets had obscured the access sites. In another case of a dislodged dialysis needle (Fields 2010), a blanket also covered the access site. So, that is a recurrent theme. Use of the blankets is a well-intentioned effort to keep the patients comfortable. But it obviously subverts the recommendation to maintain visualization of the access site at all times. We’ve previously recommended that, if a blanket is necessary, it should be one that has a substantial cut-out section that allows adequate visualization of the access site.
In their review of hemodialysis emergencies, Saha and Allon (Saha 2017) discuss venous needle dislodgement (VND) as a rare but life threatening complication of hemodialysis, noting that at a typical dialysis blood flow of 300–500 ml/min, hemorrhagic shock ensues within minutes (after loss of 30%–40% of total blood volume). They note the following major factors leading to needle dislodgement:
- Issues related to access care (improper taping of access tubing to the skin, loose luer lock tubing connection, bloodlines not being looped loosely, or access site not being visible)
- Patient factors (eg. a confused patient pulling the needle out of the access)
They describe the role of the venous alarm monitor but note that multiple factors aside from venous pressure can affect the alarm. Plus, there are differences in venous pressure between grafts and fistulas. As a result of wide variation in venous pressures, staff often set the alarm thresholds at levels below that at which a dislodgement should have triggered an alarm.
They then discuss various sensors that can detect blood leaks during VND. They note the tradeoff between safety and cost. Although blood sensors add substantially to the cost (one of the more popular sensors adds about $550), they suggest that such might be considered in high-risk patients and patients on home hemodialysis They caution, however, against overreliance on such sensors and note there is no substitute for adherence to good practices, such as those outlined by the American Nephrology Nurses’ Association (ANNA).
Axley et al. (Axley 2012) described the work of the American Nephrology Nurses’ Association (ANNA) Venous Needle Dislodgement Special Project Workgroup, which reviewed recommendations of care for venous needle dislodgement prevention and detection. They developed a set of easy-to-use tools outlining their recommendations. These focused especially on the procedures for taping and positioning of needles and lines. But they stressed that vascular access and needles should be visible at all times during hemodialysis. Checking the vascular access should be part of the monitoring routine. And, most importantly, “When the venous pressure alarm is activated, the vascular access, needle sites, and blood line positions should always be inspected prior to resetting the alarm and/or the alarm limits.” They also discussed the importance of patient and staff education about needle dislodgement, including caution that alarm systems are not infallible. They also included a risk assessment tool to help identify patients at high risk for venous needle displacement. When such high risk patients are identified, they suggest interventions such as stabilizing the access limb, using one-on-one monitoring, and consideration of a blood leak detection device.
Likewise, The Renal Association (The Renal Association 2018a) recommends that connections and lines are kept in full view of dialysis staff during dialysis, secured with tape if necessary, and that any alarm should prompt visual inspection of these. It is customary in most units to place the dialysis machine on the same side as patient access, a practice we have recommended since our first column. They recommend local dialysis nursing supervision guidelines should be adhered to, though these vary from unit to unit. Some units have double-checking of line connections by 2 nurses included in their protocols for starting dialysis.
The exact incidence of dialysis needle dislodgement is unknown but the Fields article (Fields 2010) quotes a patient survey that found 5% of dialysis patients had a needle dislodge mid-treatment within the previous three months. Saha and Allon (Saha 2017) gave estimates of the incidence of venous needle dislodgement at 1 in 60,00 to 70,000 dialysis sessions, though it occurred in 1 in 11,000 sessions in Canadian studies of home hemodialysis. Though these statistics might make the issue seem rare, the fact that so many of these cases are fatal belies the seriousness of the problem.
Hemorrhage from dislodged venous access is not the only problem. In that original alert (The Renal Association 2018a), The Renal Association noted it had also been made aware of a patient death after femoral dialysis catheter removal, due to haemorrhage. In a subsequent alert (The Renal Association 2018b), it noted that the National Reporting and Learning System of NHS Improvement provided an analysis of reports of harm from late bleeding following femoral line removal in the last 3 years. Six incidents were reported. Of these, 3 resulted in patient deaths (including the incident reported above) and 2 others resulted in the major blood loss of over 1 liter of blood.
The Renal Association recommends the following precautions and patient monitoring when the removal of a femoral dialysis catheter is planned:
- Appropriate timing of procedure. This is a semi-elective procedure: as such the responsible clinical team should ensure adequate staffing levels and appropriate competency exist to monitor the removal site and patient during and after the procedure and ensure patient comfort. The patient’s ability to comply with instruction should be considered in relation to post-procedural monitoring.
- Possibility of coagulopathy: basic coagulation studies and platelet count should be available in advance of catheter removal. Absence of high-level anticoagulation should be confirmed.
- Need to apply pressure for defined period of time, we suggest for no less than 15 minutes. Ensure complete cessation of bleeding prior to removing pressure completely and applying dressing.
- Appropriate dressing.
- Duration of bedrest; positioning in bed; subsequent level of activity. Practice varies. We suggest bedrest of at least 1 hour after the procedure.
- Level of supervision post-procedure including timing and frequency of observations. This was highlighted as a key issue by the Coroner in the most recent case.
- Appropriate patient observation post-procedure. This is particularly important for isolated and confused patients.
- Procedure should only be carried out by an appropriately trained and competent health care professional.
- Patient education and information in relation to procedure and subsequent risks should be provided verbally
- In the case of significant bleeding, Trust’s local major hemorrhage procedure should be activated
- Actions should be documented comprehensively and clearly in the clinical record, including timing of femoral catheter removal, coagulation results and length of local pressure and dressing and required observations in the notes.
- Recent removal of line should be taken into account in determining timing of safe discharge from hospital
Subsequently, a national guideline was developed in the UK. The Renal Association, The British Renal Society, and The Intensive Care Society developed a “Recommendation for the safe removal of a temporary femoral dialysis line.” (BRS 2019).
Fatal hemorrhage in dialysis patients is not confined to those actually undergoing a dialysis treatment. Jose and colleagues (Jose 2017) reviewed reports on episodes of death due to vascular access bleeding in Australia and New Zealand over a 14-year period, together with individual dialysis units’ root cause analyses on each event. They note that data from Australia and New Zealand and from the US show that the majority of fatal bleeds occur from spontaneous access rupture away from the dialysis facility (most often at home, assisted living, or a nursing home), and it is therefore likely that the family and caregivers are confronting these large bleeds rather than dialysis unit staff. Hence, the importance of educating patients and their families or caregivers on what to do in case of such bleeding.
They identified 3 broad groups of causal factors for fatal vascular access hemorrhage (FVAH), noting these may operate independently or in combination:
- Specific complications associated with the vascular access (eg. aneurysmal formation or bacterial infection leading to weakening of the vessel wall)
- Patient related factors (eg. multiple comorbid conditions and medications contributing to increased bleeding risk, reduced cognitive function and inability to self-manage an initial bleed)
- Dialysis procedure–related factors (eg. disconnection at the patient-machine interface, failed detection of needle dislodgement or catheter misconnection)
Risk factors they identified included access with a central vascular catheter (CVC) or a synthetic AV graft (AVG). (Note that the hemorrhage risk with CVC’s may relate more to catheter disconnection than to needle displacement). Physical location of the vascular access may also be important, with thigh vascular access overrepresented. Infection at the access site is also a risk factor. Finally, where the person is when the bleed occurs
may be an important risk for death. Lack of readily available expertise to manage the bleeding may explain why fatal bleeding is more common when patients were in the community (home or nursing home), rather than during a dialysis session.
Due to several reported incidents of life-threatening bleeding (LTB) or life-threatening hemorrhages (LTH) from arteriovenous fistulae (AVF) and grafts (AVG), the British Renal Society Vascular Access Special Interest Group has compiled recommendations for managing life-threatening bleeds from AV fistula /grafts (BRS 2018). Patients, carers, transport staff and emergency care staff should be educated about the action to take in the event of a LTB from an AVF/AVG.
.·Patients should dial 999 (911 in the US) immediately,for any bleeding which soaks through a dressing despite direct pressure.
oThe priority for patients in this situation is to get help
oThis should not be delayed whilst trying to stop the bleeding, as loss of consciousness can occur quickly in a life-threatening bleed
oThe priority is to stop the bleeding, not preserve AVF or AVG function
·Once help from the emergency services has been initiated, patients should continue to apply direct pressure to the bleed.
·All patients experiencing a spontaneous bleed from their AVF/AVG or felt at immediate risk of a bleed should be seen urgently by a surgeon who specializes in vascular access before they leave hospital.
Their “Do’s and Don’ts” are also very informative:
·If easily available, a small, rigid object (e.g. large bottle top, hollow side down) can be used to apply pressure over the bleeding site. This ensures pressure is localized to the area of the bleed. (Their Information for Patients brochure states “Apply firm pressure over the bleeding site, use gauze and two fingers, or a bottle top or similar can help localize pressure over the bleeding site” and provides pictures)
·Patients should be advised not to use a large absorbent item, such as a towel, as this disperses pressure reducing its effectiveness
·They do not recommend the supply of tourniquets to patients to manage LTB
The Renal Association (UK). Severe blood loss in haemodialysis patients from dialysis line disconnection and femoral catheter removal. July 23, 2018
CDPH (California Department of Public Health). Complaint Intake Number: CA00471877; posted 4/20/2017
Fields R. When Needles Dislodge, Dialysis Can Turn Deadly ProPublica 2010; Nov. 10, 2010
Saha M, Allon M. Diagnosis, Treatment, and Prevention of Hemodialysis Emergencies. Clinical Journal of the American Society of Nephrology 2017; 12(2): 357-369
Axley B, Speranza-Reid J, Williams H. Venous needle dislodgement inpatients on hemodialysis. Nephrology Nursing Journal 2012; 39(6): 435-445
The Renal Association (UK). Patient Safety Alert: response to reported death from blood loss following removal of a temporary femoral dialysis catheter. November 29, 2018
The Renal Association, The British Renal Society, The Intensive Care Society. Recommendation for the safe removal of a temporary femoral dialysis line. Accessed December 7, 2019
Jose MD, Marshall MR, Read G, et al. Fatal Dialysis Vascular Access Hemorrhage. Am J Kidney Dis 2017; 70(4): 570-575
British Renal Society. Recommendations for Managing Life-Threatening Bleeds from AV Fistulae/Grafts. Accessed December 7, 2019
British Renal Society. Information for Patients. Arteriovenous fistula (AVF) or graft
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