CHBT flashcards

31 cards. Read the term and the definition here. The deck at the top of this page is optional.

Countercurrent dialysate flow

Dialysate flows opposite to blood flow across the membrane, maintaining a concentration gradient along the full dialyzer length and maximizing diffusive solute clearance.

Transmembrane pressure

The pressure difference across the dialyzer membrane that drives ultrafiltration of plasma water; ultrafiltration rate equals the membrane coefficient multiplied by this pressure.

Kt/V adequacy measure

A dimensionless index of dialysis dose in which K is urea clearance, t is treatment time, and V is urea distribution volume; higher values indicate greater delivered clearance.

Dialysis disequilibrium syndrome

A complication of overly rapid solute removal causing cerebral edema, with headache, nausea, confusion, and possibly seizures; prevented by slower initial treatments.

Residual renal function

Remaining native kidney clearance in a dialysis patient; it contributes to solute and fluid removal and is associated with better survival and quality of life.

Dry weight concept

The post-dialysis body weight at which the patient is normotensive and free of excess fluid; it is reassessed over time as nutrition and clinical status change.

Hyperkalemia risk

Elevated serum potassium impairs cardiac conduction and can cause fatal arrhythmia; dialysis patients have reduced excretion and are especially vulnerable between treatments.

Operant conditioning model

Biofeedback works by reinforcing a physiological response through immediate feedback of the signal, strengthening the patient's ability to reproduce that response voluntarily.

Three-phase skill acquisition

Training progresses from awareness of the physiological signal, to voluntary control with the instrument present, to transfer of control into daily life without feedback.

Respiratory sinus arrhythmia

Beat-to-beat variation in heart rate across the breathing cycle; it reflects vagally mediated parasympathetic activity and rises with slow paced breathing.

Skin conductance response

A rise in electrical conductance of the skin caused by sympathetic cholinergic activation of sweat glands, used as a sensitive but nonspecific index of arousal.

Thermal biofeedback mechanism

Sympathetic arousal constricts peripheral vessels and cools the fingertips; training aims to increase finger temperature through vasodilation and reduced sympathetic tone.

Surface EMG principle

Electrodes on the skin detect electrical activity of underlying muscle; lower microvolt readings reflect reduced contraction and are used as a relaxation target.

Electrode triad placement

Surface EMG uses an active, a reference, and a ground electrode; consistent placement and skin preparation reduce artifact and improve comparability across sessions.

Skin conductance units

Electrodermal activity is measured by applying a small constant voltage across palmar electrodes and is reported in microsiemens, reflecting sweat gland activity.

Heart rate variability indices

Beat-to-beat interval data from ECG or photoplethysmography yield time-domain and frequency-domain measures that estimate autonomic balance and training response.

Biofeedback artifact sources

Movement, electrical interference, poor electrode contact, and loose leads distort signals; recognizing these prevents mistaking artifact for genuine physiological change.

Thermistor sensor lag

Finger temperature changes slowly relative to neural events, so thermal readings lag the physiological response and require patience before interpreting trends.

Session timing in dialysis

Training is typically scheduled in the first or second hour, avoiding the period when intradialytic hypotension and post-treatment fatigue are most likely.

Vascular access protection

Sensors, cuffs, and pressure devices are kept off the fistula or graft arm because compression or obstruction can compromise or thrombose the access.

Intradialytic event handling

When hypotension, cramping, or nausea occurs, training pauses while the dialysis team manages the event and resumes only when the patient is stable.

Practice block duration

Short blocks of roughly ten to twenty minutes fit within a treatment session, limiting fatigue and allowing repeated rehearsal across multiple dialysis visits.

Distraction management

Unit noise, alarms, and staff activity interfere with attention; headphones, guided scripts, and consistent cueing help the patient stay focused on feedback.

Baseline symptom assessment

Before training, the practitioner records the target symptom, its frequency and intensity, prior coping strategies, medical history, medications, and sensory limitations.

Paced breathing training

Slow breathing near six breaths per minute increases heart rate variability and parasympathetic tone; it is often the first relaxation skill taught.

Progressive muscle relaxation

Muscle groups are briefly contracted and then released, teaching the patient to discriminate tension from relaxation and to generalize the release response.

Standardized symptom scales

Repeatable instruments such as zero-to-ten ratings or validated anxiety inventories quantify symptom severity and allow progress to be tracked across sessions.

Home practice log

Brief daily practice between sessions consolidates the skill; a written log records frequency and response and supplies material for review at the next visit.

Informed consent elements

Consent discloses purpose, procedures, risks, alternatives, expected benefits, confidentiality limits, and the patient's right to withdraw at any time.

Scope of practice limits

Practitioners provide only services covered by their licensure and certification and refer patients whose needs exceed their training or legal authority.

Protected health information

Physiological recordings and session notes are identifiable health data protected under privacy law and professional codes, requiring secure storage and limited disclosure.