Air embolism during insertion and replacement of tunneled dialysis catheters: a retrospective investigation of the effect of aerostatic sheaths and over-the-wire exchange

Central venoplasty followed by 'double guidewire railroad technique' as a bailout strategy in difficult tunnelled dialysis catheter insertion

End-stage renal disease (ESRD) patients frequently encounter challenges at the time of dialysis catheter insertion from concomitantly associated with thoracic central venous obstruction (TCVO). TCVO complicates the placement of tunnelled dialysis catheters (TDCs). In cases where TCVO is unexpectedly encountered and TDC insertion becomes difficult, central venoplasty followed by catheter reinsertion is required. This report details a novel technique to salvage a TDC that was trapped at the TCVO site after removal of the peel-away sheath. We describe the case of a 67-year-old diabetic male ESRD patient on haemodialysis since 2017, with history of multiple prior accesses, who presented with acute thrombosis of his arteriovenous fistula. TDC placement was attempted via the left internal jugular vein (IJV). Angiography revealed severe stenosis at the left brachiocephalic vein-superior vena cava confluence, necessitating venoplasty. Post-venoplasty, the TDC could not be advanced past the IJV venous entry site due to unfavourable catheter tip profile. Utilising a double guidewire railroad technique, the TDC was successfully reinserted, ensuring functional dialysis. The technique carries potential risks, which mandates careful hemodynamic monitoring and prophylactic measures. In conclusion, percutaneous placement of a TDC following a central venoplasty is at times life-saving in patients with exhausted peripheral vascular access and concomitant TCVO. In the absence of a peel-away sheath, TDC reinsertion using a double guidewire railroad technique is a helpful technique for salvaging the catheter, especially in financially-constrained settings.

Evaluation of the Catheter Clamp over Hydrophilic Guide Wire Central Venous Catheter Exchange Technique for Air Embolism Prophylaxis in an In Vitro Model

PURPOSE

To develop a reproducible in vitro model simulating central venous catheter (CVC) exchange with high potential for air embolization and test the hypothesis that a closed catheter clamp over hydrophilic guide wire exchange technique will significantly reduce the volume of air introduced during CVC exchange.

MATERIALS AND METHODS

The model consisted of a 16-F valved sheath, 240-mL container, and pressure transducer submerged in water in a 1,200-mL suction canister system. Continuous wall suction was applied to the canister to maintain negative pressure at -7 mm Hg or -11 mm Hg. Each trial consisted of 0.035-inch hydrophilic guide wire introduction, over-the-wire catheter exchange, and wire removal following clinical protocol. A total of 256 trials were performed, 128 trials at each pressure with the catheter clamp open (n = 64) or closed (n = 64) around the hydrophilic guide wire.

RESULTS

There was a statistically significant lower volume of air introduced with closed clamp over-the-wire exchanges than with open clamp exchanges at both pressures (2-tailed t-test, P < .001). At -7 mm Hg, a mean of 48.0 mL (SD ± 9.3) of air was introduced with open clamp and 20.6 mL (SD ± 4.7) of air was introduced with closed clamp. At -11 mm Hg, 97.8 mL (SD ± 11.9) of air was introduced with open clamp and 37.8 mL (SD ± 6.3) of air was introduced with closed clamp.

CONCLUSIONS

This study demonstrated the use of a reproducible in vitro model mimicking conditions causing air embolism during CVC exchange. Results showed that CVC exchange using closed catheter clamp over hydrophilic guide wire exchange technique significantly reduced the volume of air introduced per exchange.

Central Line Catheters and Associated Complications: A Review

The use of a central line or central venous catheterization was brought to attention in 1929 when Dr. Werner Forssmann self-inserted a ureteric catheter through his cubital vein and into the right side of his heart. Since that time the central line technique has developed further and has become essential for the treatment of decompensating patients. Central lines are widely used for anything from rapid fluid resuscitation, to drug administration, to parenteral nutrition, and even for administering hemodialysis. Central lines come in different sizes, types, and sites of administration. Sometimes their use can be associated with complications as well. The following review article addresses these parameters of central lines and goes into detail regarding their complications.

Exchange over the guidewire from non-tunneled to tunneled hemodialysis catheters can be performed without patency loss

PURPOSE

The exchange from a non-tunneled hemodialysis catheter to a tunneled one over a guidewire using a previous venotomy has been reported to be safe. However, some concerns that it may increase infection risk prevent its clinical application. This approach seems particularly useful for acute kidney injury patients requiring initial renal replacement therapy, in whom we frequently worry about the choice of non-tunneled versus tunneled catheters.

MATERIALS AND METHODS

From March 2012 to February 2016, 88 cases to receive the over-the-guidewire exchange method from a non-tunneled to a tunneled catheter and 521 cases to receive de novo tunneled catheter placement from the hemodialysis vascular access cohort were compared retrospectively.

RESULTS

The immediate complication, later catheter dysfunction requiring replacement, and infection rates were comparable between the two groups. Newly placed tunneled catheter survival in the over-the-guidewire exchange group was comparable with survival in the de novo tunneled catheter group (p = 0.24). In addition, when we compared the same two methods among only intensive care unit patients; they remained similar (p = 0.19).

CONCLUSION

An exchange with the over-the-guidewire method from a non-tunneled to a tunneled catheter was comparable to a de novo catheter placement technique. Therefore, this method should be viewed more favorably and should especially be considered for acute kidney injury patients.

Air embolism: diagnosis and management

Air embolism is an uncommon, but potentially life-threatening event for which prompt diagnosis and management can result in significantly improved patient outcomes. Most air emboli are iatrogenic. Arterial air emboli may occur as a complication from lung biopsy, arterial catheterization or cardiopulmonary bypass. Immediate management includes placing the patient on high-flow oxygen and in the right lateral decubitus position. Venous air emboli may occur during pressurized venous infusions, or catheter manipulation. Immediate management includes placement of the patient on high-flow oxygen and in the left lateral decubitus and/or Trendelenburg position. Hyperbaric oxygen therapy is the definitive treatment which may decrease the size of air emboli by facilitating gas reabsorption, while also improving tissue oxygenation and reducing ischemic reperfusion injury.

Central line complications

Central venous access is a common procedure performed in many clinical settings for a variety of indications. Central lines are not without risk, and there are a multitude of complications that are associated with their placement. Complications can present in an immediate or delayed fashion and vary based on type of central venous access. Significant morbidity and mortality can result from complications related to central venous access. These complications can cause a significant healthcare burden in cost, hospital days, and patient quality of life. Advances in imaging, access technique, and medical devices have reduced and altered the types of complications encountered in clinical practice; but most complications still center around vascular injury, infection, and misplacement. Recognition and management of central line complications is important when caring for patients with vascular access, but prevention is the ultimate goal. This article discusses common and rare complications associated with central venous access, as well as techniques to recognize, manage, and prevent complications.