6.3 Oxygen Administration, Topical and Local Anesthetics, and Ancillary Equipment Monitoring
Key Takeaways
- Oxygen is administered by the technician only per physician order or an established standing protocol, most often 2 to 4 L/min by nasal cannula or 10 to 15 L/min by non-rebreather mask during an emergency, with immediate notification of the registered nurse.
- Topical anesthetics such as lidocaine-prilocaine cream require 30 to 60 minutes under an occlusive dressing before cannulation and can cause blanching, vasoconstriction that makes the vessel harder to enter, and rare methemoglobinemia with prilocaine.
- Intradermal lidocaine must be injected without epinephrine, in a small volume, without obscuring the vessel path, and never through the site the needle will enter; intravascular injection and needle-track contamination are the principal hazards.
- Ancillary equipment brought to the station, including intravenous pumps, oxygen concentrators, feeding pumps, and warming devices, must be monitored during treatment and inspected for damage, current preventive maintenance, and safe electrical condition.
- All patient-contact equipment shares the dialysis station clean-and-dirty boundary, so a stethoscope, blood pressure cuff, or glucose meter carried between stations must be disinfected between patients or dedicated to a single station.
6.3 Oxygen Administration, Topical and Local Anesthetics, and Ancillary Equipment Monitoring
Quick Summary: Three blueprint activities converge at the treatment station: administer oxygen per order/protocol, understand the purpose and recognize complications of topical/local anesthetics, and monitor the dialysis machine and ancillary equipment (e.g., IV pump, oxygen concentrator) during treatment. Each is a small procedure with a disproportionate capacity for harm.
Oxygen Administration
Scope. Oxygen is a drug. A technician administers it per physician order or an established standing protocol, not on independent judgment, and notifies the registered nurse immediately whenever it is started. In a witnessed emergency - air embolism, cardiac arrest, acute respiratory distress - facility emergency protocols authorize immediate application while help is summoned.
Delivery devices:
| Device | Typical flow | Approximate FiO2 | Dialysis-unit use |
|---|---|---|---|
| Nasal cannula | 1-6 L/min | 24-44% | Chronic supplemental need; mild dyspnea per protocol |
| Simple face mask | 6-10 L/min | 40-60% | Moderate distress; requires a minimum 6 L/min to flush CO2 |
| Non-rebreather mask with reservoir | 10-15 L/min | 80-95% | Air embolism, shock, cardiac or respiratory emergency |
| Bag-valve-mask | 15 L/min | up to 100% | Apnea or arrest, with trained rescuers |
Rules that generate exam items:
- A simple mask must run at 6 L/min or higher. Below that, exhaled carbon dioxide accumulates in the mask and is rebreathed.
- A non-rebreather reservoir bag must be inflated before the mask is applied and must not fully collapse on inspiration; if it does, increase the flow.
- For suspected air embolism, the response is to clamp the venous line, stop the blood pump, place the patient left lateral decubitus in Trendelenburg, administer 100% oxygen by non-rebreather, and call for emergency help.
- Oxygen supports combustion. Cylinders are secured upright in a rack or cart and never left free-standing, kept away from heat sources, and no petroleum-based products or ignition sources are permitted near them. This is a Life Safety Code issue as well as a clinical one.
- Document the indication, device, flow rate, start and stop time, the patient's response, and the notification made.
Pulse oximetry accompanies oxygen use where available, with awareness that readings are unreliable in poor perfusion, cold extremities, motion, and dark nail polish - all common at a dialysis chair.
Topical and Local Anesthetics
The purpose of anesthesia at cannulation is straightforward: pain is the most common reason patients refuse buttonhole conversion, request catheters, or shorten treatments. Effective site preparation improves both experience and access outcomes.
Topical anesthetic cream (lidocaine-prilocaine or comparable):
- Applied as a thick layer under an occlusive dressing 30 to 60 minutes before cannulation. A thin smear rubbed in does not work; the drug must sit under occlusion.
- Removed and the site then cleansed with the standard antiseptic - chlorhexidine-alcohol or povidone-iodine - and allowed to dry before the needle enters. The cream is not sterile and its presence does not replace skin antisepsis.
- Complications: local blanching and vasoconstriction that can make a vessel harder to palpate and enter, contact dermatitis, and - with prilocaine, particularly in infants, in patients with glucose-6-phosphate dehydrogenase deficiency, or with excessive application - methemoglobinemia, presenting as cyanosis with a normal arterial oxygen tension and chocolate-brown blood that does not improve with oxygen.
Intradermal or subcutaneous lidocaine:
- Use lidocaine without epinephrine. Epinephrine causes vasoconstriction that impairs access perfusion.
- Inject a small volume (commonly 0.1-0.3 mL) intradermally to raise a wheal beside, not over, the intended puncture path. A large bleb distorts landmarks and obliterates the vessel you were about to cannulate.
- Aspirate before injecting if facility protocol requires, and never inject directly into the fistula or graft. Intravascular lidocaine causes perioral numbness, tinnitus, metallic taste, dizziness, seizures, and cardiac depression.
- Do not inject through the exact spot the dialysis needle will enter; that pushes a skin plug and surface flora along the needle track.
- Watch for true allergy (rare with amide anesthetics) versus the far more common vasovagal reaction to the injection itself.
Buttonhole caution: anesthetic creams and repeated injections at a buttonhole site can macerate skin and contribute to the higher infection rate buttonhole cannulation already carries. Site care discipline matters more here than anywhere else.
Ancillary Equipment at the Station
The blueprint explicitly names monitoring the dialysis machine and ancillary equipment during treatment. Common devices:
| Device | Monitoring focus |
|---|---|
| Intravenous infusion pump | Correct rate and volume; the infused volume is added to the ultrafiltration goal; alarms audible and not silenced |
| Oxygen concentrator or cylinder | Flow setting matches the order; cylinder content adequate and secured upright; tubing not kinked or under the chair |
| Enteral feeding pump | Rate, head-of-bed position, tolerance |
| Patient-owned devices (CPAP, insulin pump, ventricular assist device) | Report presence to the nurse; never adjust settings |
| Blood warmer or patient warming device | Temperature setting, skin integrity under the device |
| Chairside monitor, glucose meter, blood pressure cuff, stethoscope | Quality control in date; disinfection between patients or dedication to one station |
Electrical and physical safety. Inspect each device before use for a current preventive-maintenance sticker, an intact three-prong plug and undamaged cord, and no cracked housing or fluid intrusion. Extension cords and power strips are not permitted for patient-care equipment in most facility policies and are a recurring survey citation. Any device that is damaged, out of maintenance date, or behaving abnormally is tagged, removed from service, and reported - it is not left plugged in with a note.
Cord and tubing management. Every added device brings a cord or line. Route them so nothing crosses a walkway, no cord runs under a chair wheel, and no line is under tension. This is where the ancillary-equipment activity meets the Environment practice area's falls and unobstructed-pathway requirements.
Infection control. All of this equipment lives inside the dialysis station and is therefore subject to the same clean-and-dirty discipline as the machine. Anything carried from station to station is disinfected between patients with an approved product at the correct contact time, or it is dedicated to a single station.
A patient is suspected of having sustained an air embolism during treatment. In addition to clamping the venous line and stopping the blood pump, which oxygen delivery approach is indicated?
A technician applies a lidocaine-prilocaine cream to a patient's fistula site 45 minutes before cannulation. Which complication of topical anesthetic use should the technician anticipate and plan for?
During rounds, a technician notices that an intravenous infusion pump at a treatment station has a frayed power cord and a preventive maintenance sticker that expired four months ago. What is the correct action?