Haemodialysis Procedures, Complications, and Patient Care Vocabulary

Comprehensive vocabulary flashcards covering cannulation, extracorporeal complications, patient-related and dialysate-related conditions, anticoagulation, equipment monitoring, and psychological aspects of ESRD.

Thrill

A constant purring or vibration felt upon palpation of a vascular access (AV fistula or graft) using clean hands or gloves.

Bruit

The acoustic sound generated by blood flow through a vascular access, audible using a stethoscope along the length of the fistula or graft.

Blue Thumb Graft

A vascular graft configuration where the arterial flow enters on the limb of the graft located medial to the body midline or heart, representing regular flow.

Red Thumb Graft

A vascular graft configuration where the arterial inflow is located on the limb distal to the body midline or heart.

Rope Ladder Technique

A cannulation method where new needle insertion sites are chosen at each treatment session, creating a distributed pattern along the access vessel.

Buttonhole Technique

A cannulation method where specialized needles repeatedly reuse the exact same two sites until permanent scar tissue tracts form.

Dry Cannulation

The standard cannulation technique where needles are inserted into the access dry, allowed to fill with flashback blood, and aspirated prior to line connection.

Wet Cannulation

A cannulation technique where a needle is attached to a syringe filled with saline and flushed to expel all air prior to insertion, used for new fistulas, difficult placements, or quick-clotting patients.

Exsanguination

Severe and potentially fatal blood loss occurring in dialysis due to bloodline separation, needle dislodgement, dialyzer membrane rupture, or access site rupture.

Access Recirculation

The re-entry of dialyzed blood returning from the venous needle directly back into the arterial suction needle without circulating through the systemic circulation.

Air Embolism

A life-threatening complication where air enters the vascular system, often due to a disarmed or defective air-in-blood detector while air is present in the extracorporeal circuit.

Dialysis Disequilibrium Syndrome

A neurological condition caused by the rapid removal of blood urea nitrogen ($\text{BUN}$) relative to urea in brain tissue and cerebrospinal fluid, leading to osmotic fluid movement into the brain.

First-Use Syndrome

A symptom complex (chest/back pain, shortness of breath, hypersensitivity) occurring when a patient is exposed to a new dialyzer, commonly linked to complement activation by cellulosic membranes or residual ethylene oxide.

Steal Syndrome

Ischemia of the distal extremity occurring when blood supply is shunted through a vascular access away from the distal limb, leading to coldness, pain, and potential tissue necrosis.

Aneurysm

A localized dilation of the vessel wall occurring most commonly at the arterial anastomosis of an AV fistula due to vessel wall weakness or repeated cannulation at the same site.

Pseudoaneurysm

A false aneurysm occurring in synthetic AV grafts where blood pools outside the graft structure with no communication with the main vessel flow, caused by unsealed puncture sites or poor haemostasis.

Haemolysis

The destruction of red blood cells during dialysis, recognizable by a cherry red appearance of blood, caused by hypotonic dialysate, overheated dialysate ($>43^\circ\text{C}$), excessive negative arterial pressure ($<-250\,\text{mmHg}$), or chemical toxins.

Crenation

The shrinkage and deformation of red blood cells caused by exposure to hypertonic dialysate or rapid administration of hypertonic saline.

Pre-blood Pump Arterial Pressure

The negative suction pressure generated by the blood pump pulling blood from the vascular access, which should not drop below $-250\,\text{mmHg}$ to prevent haemolysis.

Pre-dialyzer Arterial Pressure

The positive pressure measured after the blood pump and before the dialyzer inlet, reflecting resistance and potential clotting within the dialyzer or downstream tubing.

Venous Pressure

The positive pressure downstream of the dialyzer indicating resistance to returning blood flow through the venous drip chamber, venous tubing, and vascular access.

Mean Dialyzer Pressure

The mathematical average pressure within the dialyzer blood compartment, calculated as the sum of pre-dialyzer arterial pressure and venous pressure divided by $2$.

Clearance

The volume of blood completely cleared of a specific solute (such as urea) per unit of time, typically measured in $\text{mL/min}$.

Heparin

An anionic mucopolysaccharide anticoagulant extracted from pork intestinal mucosa or beef lung that binds antithrombin III to inactivate thrombin and coagulation factors.

Regional Citrate Dialysis

An anticoagulation method where trisodium citrate is infused pre-dialyzer to chelate ionized calcium in the circuit, combined with a zero-calcium dialysate and post-dialyzer calcium chloride infusion.

Dialysis Encephalopathy

A progressive neurological disorder characterized by speech disturbances, myoclonic jerks, and dementia, caused by aluminum accumulation from dialysate water or aluminum-based phosphate binders.

Pruritus

Severe generalized itching experienced by ESRD patients due to uremia, skin dryness, elevated calcium-phosphate product, hyperparathyroidism, or sensitivity to dialyzer sterilants.

Trendelenburg Position

A body position where the patient is laid supine with the head lowered below the feet, utilized as immediate treatment for acute hypotension or air embolism.

Depression

The most prevalent psychological complication among chronic dialysis patients, impacting physical, mental, and social functioning.

Certified Dialysis Technician

A healthcare professional formally trained in an approved dialysis program, certified to perform haemodialysis procedures under the supervision of a registered nurse in charge.