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NCCT NCET practice questions

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Question 1ECG Technician Responsibilities and Scope of Practice

An ECG technician is asked by a patient's family member to explain what the abnormal rhythm on the tracing means. What is the technician's most appropriate action?

  1. Provide the family a copy of the tracing to review with a cardiologist
  2. Explain the rhythm in simple terms so the family is reassured
  3. Interpret the tracing and suggest a likely diagnosis
  4. Decline to interpret and refer the question to the interpreting physician Correct answer.

Explanation

ECG technicians are trained to acquire and technically prepare tracings, not to render diagnostic interpretations. Interpretation belongs to the licensed clinician responsible for the patient. Redirecting the question protects both the patient and the technician's scope of practice.

Question 2ECG Technician Responsibilities and Scope of Practice

Which task falls within the standard responsibilities of an ECG technician?

  1. Deciding whether to discontinue a patient's antiarrhythmic drug
  2. Adjusting electrode placement to obtain a clean diagnostic tracing Correct answer.
  3. Ordering a repeat ECG when the first tracing looks abnormal
  4. Signing the final interpretation of the ECG report

Explanation

Technicians are accountable for acquisition quality, including correct lead placement, skin preparation, and artifact reduction. Ordering tests, altering medications, and signing interpretations are clinician responsibilities. This division keeps technical and diagnostic duties distinct.

Question 3ECG Technician Responsibilities and Scope of Practice

A technician notices the ECG machine's paper supply is nearly empty before a scheduled stress test. What is the best action?

  1. Cancel the test and send the patient to another department
  2. Ask the patient to bring paper from home
  3. Proceed and hope the paper lasts through the test
  4. Restock or replace the paper before the patient arrives Correct answer.

Explanation

Equipment readiness is a core technician responsibility, and running out of paper mid-test can lose critical tracings. Restocking before the patient arrives prevents an avoidable interruption. Canceling or shifting responsibility to the patient is unnecessary when the issue is easily corrected.

Question 4ECG Technician Responsibilities and Scope of Practice

Under what circumstance may an ECG technician disclose a patient's tracing to someone outside the care team?

  1. When the technician removes the patient's name first
  2. When the patient has authorized the release Correct answer.
  3. When the tracing looks unusual and discussion may help
  4. When the requester states they are a relative

Explanation

ECG tracings are protected health information, and disclosure requires patient authorization or another lawful basis such as treatment, payment, or operations. Family relationship alone does not create permission. Removing identifiers reduces but does not eliminate privacy obligations.

Question 5ECG Technician Responsibilities and Scope of Practice

Before attaching electrodes for a resting 12-lead ECG, the technician should first do which of the following?

  1. Ask the patient to hold their breath
  2. Confirm patient identity using two identifiers Correct answer.
  3. Set the paper speed to 50 mm/s
  4. Apply lotion to improve conduction

Explanation

Verifying identity with two identifiers is the required first step before any diagnostic procedure. It prevents tracings from being filed under the wrong patient. Breath-holding, paper speed, and skin products are addressed later or are inappropriate.

Question 6ECG Technician Responsibilities and Scope of Practice

An ECG technician is unsure whether a physician's order permits a specific additional lead view. What is the appropriate response?

  1. Clarify the order with the ordering or supervising clinician Correct answer.
  2. Skip the view and note it as unnecessary
  3. Perform the view and document it as routine
  4. Ask a coworker to sign off on the decision

Explanation

When an order is ambiguous, the technician should seek clarification rather than guess. Performing unauthorized views or omitting ordered ones both create documentation and quality problems. Clarification keeps practice within scope and protects the patient.

Question 7ECG Technician Responsibilities and Scope of Practice

Which documentation entry is most appropriate for an ECG technician to record after completing a tracing?

  1. Recommend cardiology follow-up within one week
  2. Rhythm appears to be atrial fibrillation
  3. Tracing obtained at 25 mm/s with proper lead placement; patient tolerated well Correct answer.
  4. Patient likely has left ventricular hypertrophy

Explanation

Technician documentation should describe what was done and observed technically, not diagnostic conclusions or care recommendations. Recording acquisition parameters and patient tolerance supports quality assurance. Diagnostic statements belong in the clinician's report.

Question 8ECG Technician Responsibilities and Scope of Practice

A patient asks the ECG technician whether they should stop taking a beta blocker before the test. What is the correct response?

  1. Refer the question to the prescribing clinician Correct answer.
  2. Advise taking an extra dose that morning
  3. Tell the patient it does not matter either way
  4. Advise stopping it the night before the test

Explanation

Medication decisions require prescriber knowledge of the patient's condition and the purpose of the test. The technician should not advise starting, stopping, or changing doses. Directing the question to the prescriber keeps the patient safe and the technician within scope.

Question 9ECG Technician Responsibilities and Scope of Practice

During a 12-lead ECG, the patient reports chest pressure and becomes pale and sweaty. What should the technician do first?

  1. Document the symptoms and schedule a repeat ECG next visit
  2. Ask the patient to relax and continue recording
  3. Stop and immediately notify the supervising clinician or emergency response Correct answer.
  4. Finish the tracing quickly, then notify staff

Explanation

New chest pressure with diaphoresis is a potential emergency that takes priority over completing a routine tracing. The technician should stop and activate the appropriate clinical response promptly. Delaying notification to finish the recording risks patient harm.

Question 10ECG Technician Responsibilities and Scope of Practice

An ECG technician is preparing to perform a tracing on a patient with a recent skin graft on the chest. What is the most appropriate action?

  1. Cancel the ECG permanently
  2. Place electrodes directly over the graft for accurate signal
  3. Apply extra abrasive gel over the graft to improve contact
  4. Avoid the grafted area and select alternative sites per policy Correct answer.

Explanation

Electrode sites should avoid compromised skin, including grafts and wounds, to prevent injury and infection. Alternative placements or clinician guidance should be used according to policy. Abrading or pressing on a graft can cause harm.

Question 11ECG Technician Responsibilities and Scope of Practice

Which action best demonstrates the technician's responsibility for artifact control during a resting ECG?

  1. Increasing gain to make small waveforms visible
  2. Asking the patient to breathe rapidly
  3. Cleaning and drying the skin and checking electrode adhesion Correct answer.
  4. Recording with the patient standing

Explanation

Most artifact arises from poor skin-electrode contact, movement, or interference. Proper skin preparation and secure electrodes address the root cause. Adjusting gain or changing patient position masks rather than solves the problem.

Question 12ECG Technician Responsibilities and Scope of Practice

A technician is asked to train a new hire on electrode placement. Which approach best reflects professional responsibility?

  1. Show only the limb leads and skip the precordial leads
  2. Let the new hire learn by trial and error on patients
  3. Use the facility's standardized placement protocol and verify understanding Correct answer.
  4. Teach the new hire to place leads quickly without measuring

Explanation

Consistent, standardized placement is essential because misplacement alters waveforms and can mimic pathology. Training should follow facility protocol and confirm competence. Trial-and-error learning on patients risks inaccurate tracings and patient harm.

Question 13ECG Technician Responsibilities and Scope of Practice

Which situation requires the technician to escalate to a supervisor rather than resolve independently?

  1. A patient requests a blanket during the tracing
  2. The patient's arm needs repositioning for comfort
  3. The ECG machine repeatedly produces a flat line on all leads despite troubleshooting Correct answer.
  4. A patient asks how long the test will take

Explanation

Persistent equipment failure after standard troubleshooting is a technical problem that may require biomedical service or supervisor authorization. Routine comfort measures and simple patient questions are within normal technician practice. Escalation should match the level of the problem.

Question 14ECG Technician Responsibilities and Scope of Practice

An ECG technician is asked to perform a tracing on a patient who does not speak the technician's language and has no interpreter present. What is the best course of action?

  1. Use a qualified interpreter service before proceeding Correct answer.
  2. Ask another patient who speaks the language to interpret
  3. Rely on hand gestures only and skip consent discussion
  4. Proceed without explanation to save time

Explanation

Effective communication is required for informed participation and accurate history. Qualified interpreter services support privacy and accuracy. Using another patient or skipping explanation compromises confidentiality and understanding.

Question 15ECG Technician Responsibilities and Scope of Practice

Which of the following best describes the technician's role regarding a tracing that appears technically inadequate?

  1. Interpret the tracing as normal to avoid alarming the patient
  2. Forward it as final without comment
  3. Repeat or correct the acquisition and document the technical issue Correct answer.
  4. Discard the tracing without documentation

Explanation

Technical adequacy is the technician's responsibility, so the tracing should be corrected or repeated and the issue documented. Interpretation and final clinical judgment remain with the clinician. Discarding without documentation loses important quality information.

Question 16ECG Technician Responsibilities and Scope of Practice

A physician asks the technician to initial the interpretation section of an ECG report because the physician is busy. How should the technician respond?

  1. Initial it since the physician requested it
  2. Ask another technician to initial it instead
  3. Decline and explain that interpretation sign-off requires the clinician Correct answer.
  4. Initial it only if the tracing looks normal

Explanation

Signing an interpretation certifies clinical judgment that technicians are not licensed to provide, even at a physician's request. Declining politely and clarifying the boundary protects the patient and the technician. Delegating the signature to another technician does not resolve the problem.

Question 17ECG Technician Responsibilities and Scope of Practice

Which practice best protects patient privacy during an ECG performed in a shared room?

  1. Discussing the patient's history loudly so staff can hear
  2. Leaving the tracing visible on the machine screen
  3. Posting the appointment schedule at the front desk with diagnoses
  4. Using privacy curtains or screens and speaking quietly Correct answer.

Explanation

Privacy protections extend to the physical environment, including visual and auditory exposure. Screens, curtains, and quiet conversation limit incidental disclosure. Visible tracings and public schedules with diagnoses expose protected information.

Question 18ECG Technician Responsibilities and Scope of Practice

An ECG technician notices a colleague routinely placing V1 and V2 in the wrong intercostal spaces. What is the most professional first step?

  1. Address the observation directly and notify a supervisor per policy Correct answer.
  2. Report the colleague to licensing authorities immediately
  3. Correct the tracings later without mentioning it
  4. Ignore it because placement differences are minor

Explanation

Incorrect precordial placement produces misleading waveforms and can mimic or hide pathology. The professional response is to raise the concern through appropriate channels so it can be corrected. Ignoring or silently altering tracings does not protect future patients.

Question 19ECG Technician Responsibilities and Scope of Practice

Which of the following tasks may an ECG technician perform without additional clinical authorization?

  1. Deciding to convert a resting ECG into a stress test
  2. Changing the patient's scheduled medication time
  3. Replacing worn electrodes and cleaning the equipment per policy Correct answer.
  4. Interpreting an arrhythmia for the medical record

Explanation

Routine equipment maintenance and supply replacement are standard technician duties that support quality acquisition. Medication timing, test conversion, and interpretation require clinical authorization. These boundaries define the technical scope.

Question 20ECG Technician Responsibilities and Scope of Practice

A patient refuses to have electrodes placed and becomes agitated. What is the most appropriate technician response?

  1. Document that the patient was uncooperative and leave
  2. Explain the procedure calmly and respect the refusal, notifying the clinician Correct answer.
  3. Proceed quickly while the patient is distracted
  4. Hold the patient's arm to complete the test

Explanation

Patients may refuse care, and technicians should respond with calm explanation and respect for autonomy. Physical coercion or distraction violates patient rights. Notification allows the clinician to address concerns or document the refusal appropriately.

Question 21ECG Technician Responsibilities and Scope of Practice

An ECG technician receives a verbal order to add right-sided leads for a patient with suspected right ventricular involvement. What is the correct professional action?

  1. Perform the leads, then document the order and confirm per facility policy Correct answer.
  2. Refuse because verbal orders are never acceptable
  3. Perform the leads and omit documentation to save time
  4. Wait until the next scheduled ECG to add the leads

Explanation

Verbal orders may be permitted under facility policy when properly documented and verified. The technician should follow the read-back or confirmation process and record the order accurately. Refusing outright or omitting documentation both create compliance problems.

Question 22ECG Technician Responsibilities and Scope of Practice

A technician is asked to perform an ECG on a patient enrolled in a research study that requires extra lead placements. What should the technician verify before proceeding?

  1. That the extra leads will not delay the next patient
  2. That the study protocol and consent are documented and the order is authorized Correct answer.
  3. That the technician personally agrees with the study design
  4. That the patient's family approves the extra leads

Explanation

Research-related procedures require documented consent and an authorized protocol order. The technician's role is to confirm these prerequisites and follow the approved procedure. Personal opinion or family approval does not substitute for proper authorization.

Question 23ECG Technician Responsibilities and Scope of Practice

A technician discovers that a tracing was filed under the wrong patient's name in the record. What is the most appropriate action?

  1. Ask the other patient to confirm the tracing is not theirs
  2. Delete the tracing quietly to avoid attention
  3. Report the error promptly so the record can be corrected and the event documented Correct answer.
  4. Leave it because the clinical content is unchanged

Explanation

Mislabeled records can lead to wrong clinical decisions and must be corrected through the facility's error-reporting process. Prompt reporting preserves an accurate audit trail. Quiet deletion or contacting patients directly does not correct the record properly.

Question 24ECG Technician Responsibilities and Scope of Practice

During a tracing, the technician observes a pattern suggesting a dangerous arrhythmia but is not authorized to interpret. What is the best action?

  1. Document a specific arrhythmia diagnosis in the record
  2. Stop, ensure patient safety, and urgently notify the responsible clinician Correct answer.
  3. Ask the patient whether they feel their heart is beating abnormally
  4. Complete the tracing and file it for the next routine review

Explanation

The technician must recognize when urgent clinical attention is needed without issuing a diagnosis. Ensuring safety and promptly notifying the responsible clinician balances scope with patient protection. Self-interpretation or routine filing risks dangerous delay.

Question 25ECG Technician Responsibilities and Scope of Practice

Which action by an ECG technician best reflects the principle of maintaining competence within scope?

  1. Avoiding all new equipment to reduce risk
  2. Completing facility-approved continuing education and competency checks Correct answer.
  3. Relying on memory of past protocols instead of current policy
  4. Performing procedures learned informally from a colleague without verification

Explanation

Scope of practice is supported by documented, facility-approved training and ongoing competency assessment. Informal learning without verification and reliance on outdated memory increase error risk. Avoiding new equipment does not demonstrate competence.

Question 26ECG Technician Responsibilities and Scope of Practice

Which task falls within the routine scope of practice of an ECG technician working under a physician's order?

  1. Interpreting the rhythm and writing a diagnostic impression
  2. Ordering a repeat ECG when the first one looks abnormal
  3. Applying electrodes and acquiring the standard 12-lead tracing Correct answer.
  4. Adjusting the patient's cardiac medications before the test

Explanation

The ECG technician's core function is to prepare the patient, place electrodes correctly, and acquire a technically adequate tracing. Interpretation, clinical decision-making, and medication management belong to licensed practitioners. The technician supports diagnosis by producing quality data, not by diagnosing.

Question 27ECG Technician Responsibilities and Scope of Practice

An ECG technician has completed a tracing but the physician is unavailable to review it, and the patient is stable and ready to leave. What is the appropriate action?

  1. Discard the tracing because no one reviewed it
  2. Tell the patient the results are normal so they can go
  3. Interpret the tracing and document the findings yourself
  4. File the tracing in the record for later physician review and document completion Correct answer.

Explanation

Completed tracings become part of the medical record and must be routed for physician review per facility policy. The technician documents that the test was performed and any relevant observations. Interpreting results or reassuring the patient about normality exceeds the technician's role.

Question 28ECG Technician Responsibilities and Scope of Practice

Which action reflects the technician's duty to maintain competence within the ECG scope of practice?

  1. Skipping competency checks after several years of experience
  2. Performing advanced rhythm interpretation once trained informally by a coworker
  3. Completing continuing education and following current facility protocols for ECG acquisition Correct answer.
  4. Learning new lead-placement techniques from unverified online videos only

Explanation

Staying current through approved education and adhering to facility protocols keeps skills reliable and within scope. Informal training in tasks reserved for licensed staff does not expand the technician's role. Experience alone does not substitute for ongoing competency verification.

Question 29ECG Technician Responsibilities and Scope of Practice

During a resting ECG, the patient asks the technician to explain what the squiggly lines mean and whether their heart is healthy. What is the most appropriate response?

  1. Explain the tracing in detail and give your opinion on the rhythm
  2. Refuse to speak to the patient and continue silently
  3. Acknowledge the question, explain you cannot interpret results, and refer them to the physician Correct answer.
  4. Point out the waves and tell the patient the rhythm looks fine

Explanation

Interpretation and clinical reassurance are outside the technician's scope, so the appropriate response is a courteous referral to the ordering provider. This protects the patient from incomplete or incorrect information. The technician can still explain the procedure itself in plain language.

Question 30ECG Technician Responsibilities and Scope of Practice

A technician is asked to perform an ECG on a patient who has an implanted pacemaker. Which action is most consistent with the technician's scope and responsibilities?

  1. Reprogram the pacemaker settings to a lower output
  2. Interpret the paced rhythm and document the pacing mode
  3. Disable the pacemaker temporarily to obtain a cleaner tracing
  4. Perform the tracing per protocol, note the pacemaker on the record, and alert the physician Correct answer.

Explanation

The technician acquires the tracing, records relevant device information, and communicates it so the physician can interpret the paced rhythm correctly. Device interrogation and reprogramming require specialized authorization. Interpreting pacing mode is a physician function.

Question 31ECG Technician Responsibilities and Scope of Practice

A physician verbally asks the technician to add posterior leads for a patient with suspected posterior infarction. How should the technician proceed?

  1. Perform the extra leads, document who ordered them, and label them clearly Correct answer.
  2. Refuse because additional leads are never a technician task
  3. Add the leads but leave them unlabeled to save time
  4. Interpret the extra leads and write the findings in the report

Explanation

Additional lead views are within the technician's technical skill when properly ordered, and clear labeling plus documentation of the ordering provider preserves traceability. Interpretation of the added leads remains the physician's responsibility. Refusing outright would ignore a legitimate order.

Question 32ECG Technician Responsibilities and Scope of Practice

While placing electrodes, the technician notices a small area of broken skin with slight drainage on the chest. What is the most appropriate action?

  1. Cancel the test permanently and send the patient home
  2. Avoid the affected site, choose an alternative site per protocol, and document the modification Correct answer.
  3. Place the electrode directly over the area to keep the pattern consistent
  4. Ignore the area and continue with the standard placement

Explanation

Skin integrity problems require the technician to avoid the affected area, select a protocol-approved alternative, and document the change so the physician understands the modified placement. Placing electrodes over broken skin risks contamination and poor signal. Cancelling outright is unnecessary when a safe alternative exists.

Question 33ECG Technician Responsibilities and Scope of Practice

A technician is asked to perform an ECG on a patient in contact precautions for a resistant infection. Which practice best reflects the technician's infection-control responsibility?

  1. Follow facility isolation precautions and use dedicated or properly cleaned equipment Correct answer.
  2. Reuse electrodes between patients to reduce waste
  3. Skip hand hygiene because gloves are worn
  4. Perform the ECG without informing the nursing staff of the visit

Explanation

Isolation precautions and equipment cleaning are core responsibilities that protect both patients and staff. Hand hygiene remains essential even with gloves, and single-use supplies must not be shared. Coordinating with nursing staff ensures precautions are followed correctly.

Question 34ECG Technician Responsibilities and Scope of Practice

An ECG technician is asked to perform a tracing on a patient who is confused and keeps removing the electrodes. What is the most appropriate action?

  1. Explain calmly, involve the caregiver or nurse, and attempt the tracing when the patient is cooperative Correct answer.
  2. Document that the patient was uncooperative and leave without attempting the ECG
  3. Proceed forcefully and hold the patient's arms down
  4. Apply restraints without an order to complete the test quickly

Explanation

Confused patients require calm explanation and assistance from caregivers or nursing staff to gain cooperation. Restraint or force without authorization is never acceptable and raises safety and legal concerns. Abandoning the attempt without trying reasonable measures fails the technician's responsibility to obtain the tracing.

Question 35ECG Technician Responsibilities and Scope of Practice

A technician notices that a tracing shows a very low-amplitude signal across all leads. Which action best reflects the technician's responsibility for technical quality before the patient leaves?

  1. Interpret the low amplitude as a cardiac condition in the report
  2. Check electrode contact and cable connections, correct the problem, and repeat the tracing Correct answer.
  3. Send the tracing as-is because quality control is the physician's job
  4. Increase the machine gain and label the tracing as a valid standard record

Explanation

Technical quality control is a technician responsibility, and low amplitude often reflects poor electrode contact or cable issues that can be corrected on the spot. Repeating after correction produces a valid record. Interpreting the finding or disguising it with altered gain misrepresents the data.

Question 36ECG Technician Responsibilities and Scope of Practice

A patient scheduled for an ECG mentions they are wearing a continuous glucose monitor and asks whether the ECG will damage it. What is the most appropriate technician response?

  1. Promise the ECG cannot affect any device and proceed
  2. Remove the glucose monitor yourself before the tracing
  3. Cancel the ECG indefinitely until the device is removed by the patient
  4. Explain that you cannot guarantee device effects and consult the care team or device instructions before proceeding Correct answer.

Explanation

The technician should not make assurances about device safety beyond their knowledge and should consult the care team or manufacturer guidance. Removing a patient's medical device is not a technician task. Cancelling indefinitely is unnecessary when the question can be resolved through consultation.

Question 37ECG Technician Responsibilities and Scope of Practice

A technician is asked to perform an ECG on a patient who has just finished exercising and is still sweating heavily. Which approach best reflects proper technique and responsibility?

  1. Apply electrodes immediately over wet skin to save time
  2. Interpret the tracing as showing exercise-related changes
  3. Dry the skin, prepare the sites, and proceed so the tracing is not degraded by poor contact Correct answer.
  4. Refuse the ECG until the patient is completely dry hours later

Explanation

Moisture degrades electrode contact and creates artifact, so drying and preparing the skin is a basic technical responsibility. The technician acquires a clean tracing but does not interpret exercise-related findings. Immediate placement over wet skin or indefinite delay are both poor practice.

Question 38ECG Technician Responsibilities and Scope of Practice

A technician is asked to sign a physician's name on an ECG report because the physician is off-site and the report is due. How should the technician respond?

  1. Sign the physician's name since the physician gave verbal permission
  2. Leave the interpretation blank and sign the physician's name in a different font
  3. Sign your own name in the interpretation section to complete the report
  4. Decline, because signing another person's name constitutes falsification Correct answer.

Explanation

Signing another person's name on a clinical document is falsification regardless of verbal permission and violates legal and ethical standards. The technician may document only their own actions, such as performing the tracing. The report must wait for the responsible physician's actual signature.

Question 39ECG Technician Responsibilities and Scope of Practice

A technician observes a coworker routinely documenting tracings as completed before actually performing them to save time at shift end. What is the most appropriate professional response?

  1. Report the practice through the appropriate supervisory or compliance channel Correct answer.
  2. Follow the same practice to keep the workload fair
  3. Confront the coworker publicly in front of patients
  4. Ignore it because it does not affect patient care

Explanation

Pre-documenting tests that have not been performed is falsification and creates a false medical record, so it must be reported through proper channels. Public confrontation or imitation is unprofessional, and ignoring it allows a serious integrity problem to continue. Reporting protects patients and the integrity of the record.

Question 40ECG Technician Responsibilities and Scope of Practice

An ECG technician is asked by a nurse to relay the physician's interpretation of a tracing to the patient because the physician is busy. What is the most appropriate action?

  1. Give the patient a general summary of the interpretation to be helpful
  2. Read the physician's note aloud to the patient from the chart
  3. Relay the interpretation accurately as the nurse requested
  4. Decline to relay the interpretation and ensure the physician or authorized staff communicates it Correct answer.

Explanation

Communicating a diagnosis or interpretation to a patient is the responsibility of the physician or authorized clinical staff. The technician should decline and route the communication appropriately. Paraphrasing or reading clinical notes aloud risks miscommunication and breaches the boundaries of the technician's role.

Question 41Patient Preparation, Positioning, and Electrode Placement

Before applying EEG electrodes, the tech gently abrades the scalp with a mild abrasive to lower skin impedance. What is the primary purpose of achieving low electrode impedance?

  1. To improve the signal-to-noise ratio of recorded brain activity Correct answer.
  2. To eliminate the need for a reference electrode
  3. To shorten the total recording time
  4. To increase the amplitude of the 60 Hz artifact

Explanation

Low impedance between electrode and skin improves the fidelity of the recorded signal by reducing noise and artifact contamination. A well-prepared scalp allows cerebral activity to be recorded with fewer extraneous signals. High impedance degrades signal quality and increases susceptibility to artifact.

Question 42Patient Preparation, Positioning, and Electrode Placement

According to the international 10-20 system, which electrode is placed at the midline of the scalp at the back of the head?

  1. Oz Correct answer.
  2. Cz
  3. Fpz
  4. Fz

Explanation

In the 10-20 system, the letter O designates the occipital region and z indicates the midline. Oz is therefore the midline occipital electrode at the posterior of the head. Cz is the midline central electrode and Fpz is midline frontopolar.

Question 43Patient Preparation, Positioning, and Electrode Placement

A tech is applying electrodes to a patient with thick hair. Which action best ensures consistent impedance across all electrode sites?

  1. Applying extra conductive paste only to the occipital electrodes
  2. Placing all electrodes on the side of the head with less hair
  3. Parting the hair and cleaning each site individually before applying the electrode Correct answer.
  4. Skipping the abrasive step on sites where hair is dense

Explanation

Consistent site-by-site preparation, including parting hair and cleaning the scalp, produces uniform impedance. Uneven preparation leads to variable signal quality and artifacts. Every electrode site should receive the same preparation technique.

Question 44Patient Preparation, Positioning, and Electrode Placement

Which measurement is used to verify the distance between the nasion and inion when laying out the 10-20 system?

  1. The total midline distance used to locate the frontal and parietal midline electrodes Correct answer.
  2. The circumference of the head at the level of the eyebrows
  3. The width of the patient's forehead
  4. The distance between the two preauricular points only

Explanation

The nasion-to-inion distance establishes the midline reference used to place Fz, Cz, and Pz at proportional intervals. This measurement is fundamental to accurate 10-20 layout. Other measurements address different dimensions of the head.

Question 45Patient Preparation, Positioning, and Electrode Placement

When the tech measures from the preauricular point to the vertex on each side, which electrode location is being verified?

  1. T3
  2. Fp1
  3. O1
  4. Cz Correct answer.

Explanation

The preauricular points on each side are used to establish the coronal plane through the vertex, where Cz is placed. Measuring from each preauricular point to the vertex confirms the central midline position. The temporal, occipital, and frontopolar electrodes are located by other reference points.

Question 46Patient Preparation, Positioning, and Electrode Placement

Which electrode serves as the most common reference for referential montages in routine EEG?

  1. Linked ears or a single ear electrode Correct answer.
  2. Cz at the vertex
  3. Fpz at the midline forehead
  4. Oz at the midline occipital region

Explanation

Ear electrodes, often linked, are widely used as a reference in referential montages because they are relatively inactive. Using an active scalp site such as Cz as reference would introduce cerebral activity into every channel. Reference selection affects how the montage displays the signal.

Question 47Patient Preparation, Positioning, and Electrode Placement

A patient arrives for an EEG with hair that is heavily oiled and styled with gel. What is the most appropriate action before electrode placement?

  1. Postpone the study indefinitely until the patient's hair is cut
  2. Cleanse and dry the scalp sites to remove oils and product residue Correct answer.
  3. Increase the amplifier sensitivity to compensate for poor contact
  4. Apply electrodes directly over the product to save time

Explanation

Oils and styling products increase impedance and degrade signal quality, so the scalp must be cleansed before electrodes are applied. Proper cleansing restores reliable contact at each site. Amplifier settings cannot substitute for good electrode preparation.

Question 48Patient Preparation, Positioning, and Electrode Placement

During electrode application, the tech notices one electrode has markedly higher impedance than the others. What is the best first step?

  1. Re-prepare the site and reapply the electrode Correct answer.
  2. Lower the impedance threshold for the entire study
  3. Exclude that channel from the montage
  4. Double the amount of paste on the adjacent electrodes

Explanation

A single high-impedance electrode usually reflects inadequate site preparation or poor contact, so re-preparing and reapplying is the appropriate corrective action. Addressing the individual site restores uniform impedance. Altering thresholds or adjacent sites does not fix the underlying problem.

Question 49Patient Preparation, Positioning, and Electrode Placement

Which patient instruction is most important to give before beginning an EEG recording?

  1. Remain still and relax with eyes closed as directed Correct answer.
  2. Chew gum continuously throughout the study
  3. Keep the eyes open and blink frequently
  4. Talk softly to the tech during the recording

Explanation

Stillness and relaxation reduce muscle and movement artifact, and eye closure is part of standard activation procedures. Chewing, frequent blinking, and talking all introduce artifact. Clear instructions before recording improve data quality.

Question 50Patient Preparation, Positioning, and Electrode Placement

A tech is preparing a patient for hyperventilation as an activation procedure. Which instruction is correct?

  1. Hyperventilate only if the patient feels dizzy
  2. Hold the breath for as long as possible
  3. Breathe normally but with the eyes tightly closed
  4. Breathe deeply and rapidly for the specified duration while the tech observes Correct answer.

Explanation

Hyperventilation activation requires deep, rapid breathing for a set period while the tech monitors the patient. Breath-holding is a different maneuver and is not hyperventilation. The tech observes for changes and patient tolerance throughout.