16.1 Medical Devices: Venous Access, Pumps, Shunts, and Tubes

CPHON Test Content Outline (TCO) IV.C.1 tests medical devices as supportive-care hardware: venous access, pumps, shunts, and tubes. It is not the surgical-placement chapter restated, and it is not the vesicant-extravasation emergency algorithm. A 4-year-old with B-lymphoblastic leukemia and an implanted port, a 9-month-old with a tunneled Broviac for infant acute lymphoblastic leukemia (ALL), a 16-year-old with a peripherally inserted central catheter (PICC) after osteosarcoma resection, and a 7-year-old with a ventriculoperitoneal (VP) shunt after medulloblastoma surgery are the same domain at different ages.

Venous access: match the device to the child and the drug

Implanted ports combine a subcutaneous reservoir with a catheter that ends in a central vein. Intact skin covers the device when it is not accessed, which is why school-age children on months of intermittent chemotherapy often receive ports: they can bathe without a dangling lumen, wear a backpack, and—once the incision is healed and the port is not accessed—often swim if the institution allows it. Access is with a noncoring Huber needle of the correct length and gauge. A standard hypodermic cores the septum, leaks, and is the wrong tool. Confirm blood return before any vesicant (vincristine, doxorubicin, daunorubicin). No blood return means you do not hang the vesicant. Reposition, have the child cough or raise the ipsilateral arm, attempt a protocolized saline flush without force, and obtain a dye study if ordered. Clinic running late is not an indication to push through.

Tunneled cuffed catheters (Broviac, Hickman) exit the chest wall after a subcutaneous tunnel; a Dacron cuff scars into the tunnel and anchors the line. Infants and toddlers who need frequent blood draws, parenteral nutrition, or continuous infusions commonly receive a Broviac because daily Huber sticks on a tiny chest are unreliable and cruel. External lumens need clamps, needleless caps, and a caregiver who can recognize a break. A snapped Broviac in a grocery-store parking lot is clamp-the-line, cover the break, and call—not wait until Monday.

PICCs enter a peripheral vein and terminate centrally. They are useful for weeks of antibiotics, nutrition, or a defined chemotherapy block when a port is not yet placed or is infected. A PICC is still a central line for central-line–associated bloodstream infection (CLABSI) counting. Toddlers pull them; securement and a wrap the child cannot unwind are nursing interventions, not decoration. Measure and document external length so a silent migration is visible.

Peripheral intravenous catheters are for short, non-vesicant, non-irritant infusions and for emergency access. Do not infuse a known vesicant into a “good” hand vein because the port looked hard. If a peripheral is the only option in a true emergency, stay at the bedside, verify blood return throughout, and convert to central access as soon as it is safe.

Access technique, chlorhexidine, dressings, occlusion, and CLABSI

CLABSI prevention bundles are the exam product: hand hygiene before every access, chlorhexidine skin antisepsis (age-appropriate—follow the unit’s infant or neonate exception rather than painting a premature infant with adult chlorhexidine against policy), sterile port access, scrub-the-hub, a transparent dressing changed on a schedule and whenever it is soiled or loose, and a daily question of whether the line is still needed. Do not invent a single ONCC dressing-day interval. Institutional bundles exist because every extra day of an unused Broviac is infection risk.

Occlusion is mechanical (kink, pinch-off, malposition), thrombotic, or chemical precipitate. Never force a flush. Alteplase (tPA) dwell for occluded central catheters is per protocol after you have excluded a kink you can see. Lipid or drug precipitate may need a different restoration agent from pharmacy—not more tPA as a reflex. A 4-year-old whose port has no blood return on a vincristine day does not get the vesicant. A 9-month-old whose Broviac dressing is peeling after a feverish night needs a sterile dressing change and an exit-site look, not tape over dirt.

Pumps, shunts, tubes, epidurals, and home policies

Infusion pumps deliver chemotherapy at locked rates (agents such as blinatumomab or high-dose methotrexate must not be bolused to “catch up”), patient-controlled analgesia (PCA) (no PCA-by-proxy unless a protocolized authorized-agent pathway exists), and enteral feeding. Alarms are clinical data: occlusion, air-in-line, and empty cassette are not “just pump noise.” Teach families the difference between a keep-vein-open saline pump and a cytotoxic infusion.

VP shunts after brain-tumor resection divert cerebrospinal fluid into the peritoneum. Malfunction presents as headache, vomiting, lethargy, irritability, or a bulging fontanelle in an infant—rising intracranial pressure until proven otherwise. Infection presents as fever, redness along the shunt tract, or peritonitis. Do not send a 7-year-old with morning vomiting after medulloblastoma home as “chemo nausea” until you have thought about the shunt.

Nasogastric (NG), nasojejunal (NJ), and gastrostomy (G-tube) tubes keep calories moving through mucositis, abdominal radiation, or neurologic injury. Confirm placement per policy before feeding; auscultation alone is not a national gold standard. A G-tube that is leaking, buried, or accidentally pulled is a same-day surgical or interventional conversation in a neutropenic child. Chest tubes after thoracotomy or for malignant effusion: watch output character and air leak, keep the drainage system below the chest, and never clamp a bubbling tube so the child can “take a walk.” Nephrostomy tubes after renal or pelvic obstruction: bag below the kidney, no kinks, and cloudy output plus fever is infection until proven otherwise. Epidural catheters for postoperative or tumor pain: keep the site clean, watch motor block and urinary retention, and never inject a chemotherapy syringe into an epidural hub.

Home-care teaching is return demonstration: flush, clamp, dressing, fever number, and what a line break looks like. Swimming with a healed, unaccessed port is often allowed; swimming with an accessed port, a PICC, or an external Broviac is institutional. Do not invent a national ONCC swim rule. Teach the family’s actual policy.

The CPHON product is a vesicant that never leaves the bag without blood return, a Huber needle instead of a coring needle, a CLABSI bundle that includes chlorhexidine and a dressing that is actually intact, a pump alarm that is treated as data, a shunt headache that is not labeled nausea, and a parent who can clamp a broken Broviac at 02:00.