Anchoring strain relief member

A method comprising

• providing an outer catheter that comprises:
• an outer catheter hub and an outer catheter shaft comprising an outer catheter lumen, an outer catheter inner surface, and an outer catheter outer surface, with the outer catheter hub being connected to the outer catheter shaft to provide fluid communication between the outer catheter hub and the outer catheter lumen;
• providing an inner catheter that comprises:
• an inner catheter hub, an anchoring strain relief member, and an inner catheter shaft comprising an inner catheter lumen with a central axis, an inner catheter inner surface, and an inner catheter outer surface, with the inner catheter hub being connected to the inner catheter shaft to provide fluid communication between the inner catheter hub and the inner catheter lumen, with the anchoring strain relief member being sealingly joined to the inner catheter outer surface;
• providing a connector that comprises a body with a connector lumen, a first opening into the connector lumen with an elastomeric sealing member, the sealing member providing a seal across the first opening, a hemostatic valve at a second opening into the connector lumen and a side port providing fluid communication with the connector lumen;
• attaching the connector to the outer catheter hub in fluid communication with the outer catheter lumen;
• passing the inner catheter shaft through the first opening and the sealing member and into the outer catheter lumen, with the connector being in fluid communication through the second opening with an annulus formed between the inner catheter outer surface and the outer catheter inner surface;
• positioning a sealing portion of the strain relief member within the sealing member, with the sealing member pressing against the sealing portion of the strain relief member to establish a seal and to resist movement of the inner catheter relative to the outer catheter forming nested catheters;
• and
• delivering a first fluid through the inner catheter lumen and a second fluid through the side port of the connector to the outer catheter lumen, wherein the first fluid and the second fluid combine at a distal end of the inner catheter and a distal end of the outer catheter within a patient.