Urinary Catheterization and Enemas - Study Notes

Bladder Scanning and Post-Void Residual

  • Purpose of bladder scanning: non-invasive ultrasound-like device to estimate how much urine remains in the bladder (post-void residual, PVR) when a patient hasn’t voided adequately (e.g., “it’s been eight hours… assess your bladder to see if it’s still full”).
  • When to use: to investigate urinary retention and guide management after a patient hasn’t voided for an extended period.
  • How a bladder scanner works (generic): applies gel to a probe head, places the probe on the abdomen a few centimeters above the pubic bone, and scans to measure bladder fluid in milliliters (mL).
  • Probe positioning and technique:
    • Draw an imaginary line from the navel to the pubic bone; place the probe about 3–5 cm above the top of the pubic bone.
    • Hold the probe along the body diagram on the device; press the scan button to start.
    • Move the probe from the target location toward the bladder and slowly raise until you find the largest bladder area.
    • Do not lift the probe more than 90° from the abdomen.
    • During pre-scan, the latter point and a green light help ensure accuracy.
    • After optimal position, press scan again and hold steady until the scan completes.
  • Interpreting results:
    • Readings should place the bladder image near the center for best accuracy.
    • You may take multiple measurements (slight repositioning) and use the highest reliable reading.
    • Proper anatomical location and central alignment improve accuracy; multiple attempts may be needed.
  • Practical notes:
    • Do not tilt the scan head beyond 90°.
    • If unsure, repeat in the same general location and choose the best reading.
    • Use bladder scan to determine post-void residual and guide interventions (e.g., further evaluation or catheterization).
  • Clinical rationale: if a patient has been in the hospital for an extended period without voiding, scanning helps identify whether urinary retention is the cause of symptoms and informs next steps (e.g., voiding trials, catheterization).
  • Distinctions:
    • “Plain” bladder scan vs. post-void residual measurement: the scan can estimate residual volume after voiding or indicate an ongoing retention problem.

Post-void Residual (PVR) and Retention

  • Definition: residual means what is left in the bladder after the patient voids.
  • Use of PVR: to assess who has retention and to quantify how much urine remains after voiding.
  • Context for use: when symptoms or clinical history suggest urinary retention (e.g., long duration without voiding, abdominal distension, or recurrent UTIs).

Urinary Catheter Types and Indications

  • Coude catheter:
    • Has a curved tip to bypass obstructions in the urethra, such as an enlarged prostate in males.
    • Helpful when there is suspected prostatic obstruction or scar tissue that makes passage through the urethra harder.
    • Policy note from a hospital example: some facilities automatically use a Coude catheter for males above a certain age (e.g., age ~50–55) to accommodate potential prostatic enlargement; even if the patient doesn’t have a known prostate problem, it’s commonly used to reduce resistance.
  • Foley catheter (indwelling/continuous):
    • Most common indwelling catheter; contains a balloon to hold the catheter in the bladder.
    • Variants shown: D, E, F (E has a Coude tip).
    • Balloon and lumen configurations discussed below.
  • Suprapubic catheter:
    • Inserted surgically through the abdominal wall directly into the bladder (vesicostomy).
    • Bypasses the urethra when urethral access is blocked or not feasible.
  • External catheters (non-invasive):
    • Condom catheter for males: placed externally over the penis; important to secure securely (not too loose to fall off, not too tight to restrict blood flow).
    • Female external catheter (PureWick): adhesive wings, placed externally around the genitalia, connected to suction canister; urine is collected by suction;
    • External devices require continuous monitoring for skin integrity and proper suction function.
  • Other catheter types mentioned (less common but relevant):
    • Male cut or dehepizier/mushroom catheters (used to drain the renal pelvis under cystoscopy).
    • Robinson catheter (a type of straight catheter; red color; may be latex, so latex allergy is a consideration).
    • Ureteral catheters (long, slender, passed into the ureters; typically inserted by physicians with specialized equipment; not routine nursing insertion).
    • Whistle tip catheters (end with a larger orifice to allow drainage of blood clots and debris).
  • Self-catheterization: patients may self-catheterize using a straight catheter if neuro conditions or muscle weakness impair normal urination.
  • Catheterization in practice notes: certain advanced catheters or procedures (e.g., catheterization requiring cystoscopy or ureteral access) are performed by physicians or specially trained providers.

Catheter Components and Lumens

  • Lumen concept:
    • Single lumen: a single channel in the catheter, used for drainage only.
    • Double lumen: two channels — one for urine drainage, one to inflate the balloon with saline.
    • Triple lumen: three channels — urine drainage, balloon inflation, and irrigation (or another dedicated channel).
    • Lumens are separated inside the tube by a wall.
  • Balloons and inflation:
    • Balloons are inflated with sterile saline via a syringe connected to the balloon port.
  • Examples of lumen configurations:
    • D and E: both are Foley-style catheters; E has a Coude tip.
    • F: another indwelling variant with multiple lumens.
  • External catheters lack internal lumens for drainage; they rely on the collection system outside the body.

Catheter Sizing and Balloon Volumes

  • Catheter sizing: French system (F). Larger numbers indicate a larger outer diameter.
    • Typical adult ranges: about
    • female: 14–16 French (
      F o ext{diameter}
      ),
    • male: 16–18 French.
    • Pediatric sizes: roughly 3–10 French.
    • Range overall: approximately 3–34 French depending on patient size and purpose.
  • Balloon sizes:
    • Common indwelling Foley balloons are 5–10 mL (
      V_{ ext{balloon}}
      ).
    • Pediatric catheters may use as low as 3 mL.
    • Larger balloons (up to around 75 mL) may be used postoperatively to apply pressure and aid hemostasis.
  • Balloon filling specifics:
    • In practice, a kit often includes a 5–10 mL syringe to inflate the balloon; the exact volume is specified by the kit and order.
  • Additional notes:
    • Balloon volume is chosen to securely anchor the catheter without causing urethral injury.
    • Inflation volume is the amount of sterile saline used; the nurse documents the exact amount used.

Insertion and Removal Procedures (Overview)

  • Prerequisites for any catheter insertion:
    • Obtain and review orders; ensure the correct size and type as ordered.
    • Gather supplies and ensure a sterile field; check patient allergies (latex, Betadine/iodine, etc.).
    • Identify patient and provide privacy; greet the patient.
    • If needed, prepare a second sterile glove set (backup in case of contamination or breakage).
  • General approach to both genders:
    • Male: typically two steps (preparation, then insertion along the urethra); often easier due to a single urethral opening.
    • Female: more challenging due to anatomy; labia separation and careful cleansing of the urethral meatus are required; ensure insertion is into the urethra, not the vagina (if mistakenly placed in the vagina, remove and use a new sterile catheter).
  • Insertion steps (high level):
    • Position patient appropriately (supine for males; dorsal recumbent for females).
    • Maintain sterile technique; prepare and drape; lubricate the catheter tip; avoid contaminating the sterile field.
    • For males: insert with patient bearing down; advance to the bifurcation of the urethra until urine flow; then advance 2–3 inches more as needed to reach the bladder.
    • For females: separate labia with nondominant hand; insert into the urethral opening after cleansing; advance 2–3 inches past the meatus once urine appears.
    • Inflate balloon with the prescribed saline volume (typically 5–10 mL for basic polycatheters; confirm exact volume on kit).
    • Gently tug the catheter to seat the balloon at the bladder neck; secure the catheter to the patient’s leg (or abdomen for males) and connect to the drainage bag positioned below the bladder.
  • After insertion: ensure proper securement and patient comfort; document details (time, size, balloon volume inflated, urine characteristics).
  • Removal (non-sterile removal):
    • Deflate the balloon with a 10 mL syringe by attaching to the balloon port and aspirating the saline.
    • Detach from securing device and drainage bag; gently withdraw the catheter.
    • Perform peri care and position patient comfortably after removal.
  • Special cautions during insertion/removal:
    • Insertion should be performed with sterile technique; removal is not a sterile procedure.
    • If resistance is met during insertion, reassess; contact physician if unable to advance.
    • If pain occurs during inflation, stop, deflate, and attempt again.
    • If blood is seen, suspect misplacement (e.g., vagina) and stop, remove, and reattempt with a new catheter.
  • Documentation after catheterization:
    • Time of insertion, catheter type and size, balloon volume used, urine output at insertion, and any observations.
    • For specimens: do not sample from collection bag; clamp tubing to collect urine from the port, then withdraw 5–10 mL through a sterile syringe, and label accordingly.

Catheter Care and Maintenance

  • Routine care: perform peri-care every 8 hours; clean the first two inches of the external catheter with each care cycle; avoid powders/lotions in the peri area.
  • Skin assessment: inspect around the meatus and perineum for irritation or skin breakdown; monitor for pressure injuries near the securing device.
  • Tubing and bag management: keep the drainage bag below bladder level to ensure gravity-assisted drainage; prevent kinks or disconnections; change tubing or bag if there is leakage, odor, or sediment buildup.
  • Output monitoring: record intake and output to track urinary function; typical goals include intake around
    ext{Intake}_{ ext{day}} \approx 2000 \,\text{mL}
    and output around
    \text{Output rate} \approx 30 \,\text{mL/hour}.
  • Patency checks: routinely assess catheter patency; if the bag is empty, troubleshoot for kinks or disconnections before removing the catheter.
  • Specimen collection from catheter:
    • Do not obtain specimens from the drainage bag.
    • Clamp the tubing for about 20–30 minutes to allow urine to accumulate near the port.
    • Clean the port with an antiseptic wipe, then withdraw urine through a sterile syringe (typically 5–10 mL) for culture or other tests; reconnect and unclamp to resume drainage.
  • Patient education and discharge planning:
    • Teach hydration and catheter care basics; emphasize keeping the bag below the bladder when ambulating;
    • instruct signs of infection or complications (fever, foul odor, sudden color changes, flank pain);
    • provide guidance on how to manage the catheter at home if discharged with a catheter.

Female vs Male Catheterization Differences

  • Anatomical considerations:
    • Males have a single urethral opening; females have a shorter urethra and a different anatomy (labia, vaginal opening nearby).
    • In females, cleansing requires spreading the labia and thoroughly cleansing around the urethral opening.
  • Specific precautions:
    • If catheterization occurs in a woman and enters the vagina by mistake, do not reuse that catheter; start with a new sterile catheter.
    • In a male, circumcision status changes cleansing technique; prep area to avoid contamination.
  • OB and anatomy considerations:
    • In obstetric/gynecologic contexts, catheterization can be more challenging due to swollen tissues; first opportunities in OB may be easier due to dilation, but seek experienced practice when available.

Catheter-Associated Complications and Troubleshooting

  • Potential issues and responses:
    • Resistance during insertion: hold catheter against resistance, have patient bear down, consider consulting physician or using a specialized catheter (e.g., Coude);
    • Pain during inflation: stop, deflate, and reinsert or reposition; ensure you are in the bladder, not the urethra or vagina.
    • Blood in urine: may indicate misplacement; remove catheter and start again with a new sterile catheter.
    • Catheter dislodgment or leakage: secure tubing, reassess positioning; ensure the balloon is seated at the bladder neck.
  • Routine care reminders:
    • Secure catheter tubing to prevent tugging or pulling that could injure the urethra.
    • Ensure collection bag remains below bladder level at all times to prevent backflow.
    • Track urine color, odor, and presence of sediment; note any signs of infection (hematuria or pyuria).

Specimen Collection from Catheters

  • Do not draw samples from the collection bag.
  • Method to obtain urine sample from catheter port:
    • Clamp tubing for 20–30 minutes to allow urine to collect near the access port.
    • Clean the port with an antiseptic.
    • Use a sterile syringe (e.g., 10 mL) to withdraw the required volume (commonly 5–10 mL).
    • Label and send specimen to the lab as ordered.
    • Unclamp the tubing to resume drainage.

Enemas: Types, Indications, and Administration

  • Indications for enemas:
    • Promote defecation in constipation, bowel prep before surgery or diagnostic procedures, cleanse bowel for impaction relief, or administer medications.
  • Types of enemas:
    • Cleansing enema: typically normal saline (isotonic) to stimulate defecation; large-volume (roughly 500–1000 mL) for bowel prep.
    • Small-volume enema: less than 500 mL; targets lower bowel segments.
    • Fleet enema (prepackaged): hypertonic solution; draws water into the bowel to stimulate stool passage; may contain castile soap for irritation to increase peristalsis.
    • Soap-suds enema (Castile soap): adds soap suds to irritate the bowel to promote peristalsis.
    • Oil retention enema: lubricates and softens stool to ease passage.
    • Potassium-lowering enema (e.g., Kayexalate sodium polystyrene sulfonate): used in certain hyperkalemia scenarios.
  • Tonicity and safety notes:
    • Isotonic solutions (e.g., normal saline) are generally safest because they do not cause shifts in body fluids.
    • Tap water enemas are hypotonic and can lead to circulatory overload or electrolyte shifts if repeated; do not repeat after the first installation.
    • Hypertonic solutions draw fluid into the bowel; can cause dehydration in fluid-overloaded or dehydrated patients.
    • The amount and type of solution depend on orders; follow specific prescriptions.
  • Contraindications and cautions:
    • Contraindications include paralytic ileus, chronic obstruction, circulatory overload, perforation, or recent GI surgery with risk of suture disruption.
    • Do not perform enemas multiple times in a row beyond orders (maximum often three times); avoid electrolyte imbalance.
  • Administration procedure (general):
    • Use left lateral Sims position with the left side down and the right leg flexed; gravity assists flow from bag positioned above the patient.
    • Elevate the enema bag to control flow; higher positioning increases flow rate (30–45 cm/12–18 inches for high enema).
    • Check temperature: solution should be body temperature (not hot or cold) to minimize mucosal irritation and cramping; test by placing on the inner wrist.
    • For administration, insert the rectal tube with lubricated tip, angle toward the umbilicus, and administer slowly with the clamp open until the desired amount enters.
    • Monitor patient comfort; if cramping occurs, lower the bag to slow flow.
    • After instillation, clamp the tube; assist patient to evacuate as appropriate, and advise retention time (often about ten minutes, per orders).
  • Depth of insertion by age (rectal tube):
    • Infants: approximately 1–1.5 inches.
    • Children: approximately 2–3 inches.
    • Adults: approximately 3–4 inches.
  • Documentation and patient education:
    • Record the type and volume of enema used, clinical condition, abdominal distension, bowel sounds, and intake/output if relevant.
    • Instruct patient on retention time and safety (e.g., bathroom proximity, bedpan, or commode readiness).
  • Practical notes and tips:
    • Elevation of the solution (bag height) drives flow rate via gravity; adjust if cramping occurs.
    • Adequate retention time improves effectiveness, especially when medications are infused.

Patient Care, Privacy, and Documentation

  • Privacy and consent: always provide privacy and explain the procedure; verify identity and order; check allergies (latex, Betadine, etc.).
  • Equipment readiness: ensure all supplies are ready and within reach; confirm kit contents and compatibility with patient needs.
  • Documentation essentials:
    • For catheter insertion: time, size, type, balloon volume; initial urine output; any anomalies or patient tolerance.
    • For catheter removal: time and notes on deflation, removal process, and post-removal urine characteristics.
    • For specimens: source, volume, container type, and lab orders; record any deviations from standard procedure.
  • Ethical and practical implications:
    • Respect patient dignity and privacy during intimate procedures; ensure consent and explain each step.
    • Ensure sterile technique when required, but recognize that some steps (e.g., removal) are non-sterile.
    • Be mindful of potential risks (infection, urethral trauma, skin breakdown) and monitor accordingly.

Quick Reference Numbers and Formulas

  • Bladder scan measurements:
    • Measure bladder fluid in milliliters (mL); align the bladder image to the center for accuracy.
    • No fixed universal threshold here; interpret in context with patient symptoms and history.
  • Catheter sizing and volumes:
    • Catheter sizes:
      3 \le F \le 34 \quad \text{(French size)}
    • Typical adult sizes: female $14$–$16$ French; male $16$–$18$ French.
    • Balloon volume:
      V_{balloon} \approx 5\text{--}10 \text{ mL (standard)}, with pediatric around $3 \text{ mL}$ and some cases up to $75 \text{ mL}$ for postoperative hemostasis.
  • Enema heights (gravity-driven flow):
    • High enema: h \approx 30\text{--}45 \text{ cm} \; (12\text{--}18\;\text{inches})
    • Regular enema: h \approx 30 \text{ cm}
    • Low enema: h \approx 7.5 \text{ cm}
  • Fluid guidelines (daily and hourly):
    • Daily intake target: \text{Intake}_{\text{day}} \approx 2000\;\text{mL}
    • Output target: \text{Output}_{\text{hour}} \approx 30\;\text{mL/hour}
  • Insertion depths by age for rectal enema tubes (approximate):
    • Infants: d \approx 1\text{--}1.5\text{ inches}
    • Children: d \approx 2\text{--}3\text{ inches}
    • Adults: d \approx 3\text{--}4\text{ inches}
  • Maximum enema repetitions: up to 3 times unless otherwise ordered.
  • Sample collection from catheter port: typically 5\text{--}10\;\text{mL} drawn with a sterile syringe after clamping for 20–30 minutes.

Glossary of Key Terms

  • Post-void residual (PVR): amount of urine remaining in the bladder after voiding.
  • Hematuria: blood in urine.
  • Pyuria: pus in urine.
  • Lumens: pathways inside a catheter; single, double, or triple lumen definitions.
  • Vesicostomy: surgical opening into the bladder from the abdomen.
  • Foley catheter: indwelling catheter with a balloon for retention.
  • Coude catheter: catheter with a curved tip designed to bypass urethral obstruction.
  • Ureteral catheter: catheter advanced into the ureters for specialized procedures.
  • Whistle tip: catheter tip designed to allow debris and clots to pass.
  • Kayexalate: a potassium-binding enema or other potassium-lowering enema formulation used in select clinical situations.
  • Peri care: perineal care; maintaining cleanliness around the urethral opening and surrounding skin.
  • Fenestrated drape: sterile drape with a hole to isolate the genital area while preserving a sterile field.
  • Sims position: left lateral decubitus position used for enemas and certain rectal procedures.
  • OB considerations: vaginal or cervical anatomy can influence catheter insertion; special considerations in obstetric contexts.

Ethical and Practical Implications

  • Patient dignity and consent: uphold privacy and explain each step; verify identity and allergy status.
  • Invasive vs non-invasive: reserve indwelling catheter use for retention, procedures, or where non-invasive methods would be unsafe or ineffective.
  • Documentation: accurate and comprehensive charting of procedures, measurements, and observations to support safety and continuity of care.
  • Education: empower patients and families with knowledge about catheter care, signs of infection, and when to seek care after discharge.
  • Lab training vs clinical practice: lab mannequins may not utilize all real-life solutions (e.g., Betadine); adjust for educational settings while maintaining safety in real patients.

Summary of Practical Workflow (Integrated View)

  • Assess need for bladder scan if a patient hasn’t voided for an extended period to check for retention and plan management.
  • If catheterization is indicated, choose the appropriate catheter type based on anatomy, obstruction risk, and physician order (e.g., Coude for suspected prostatic obstruction in males).
  • Prepare sterile field and equipment; perform insertion with strict asepsis for the patient’s safety and comfort; confirm placement with urine flow and appropriate balloon inflation.
  • Secure catheter and connect to gravity-driven drainage bag below the bladder level; document critical details.
  • Implement ongoing catheter care every 8 hours and with any necessary peri-care; monitor skin integrity and infection signs.
  • Obtain any required urine samples via port, not from the drainage bag, using sterile technique.
  • Educate the patient and family on catheter care, hydration, recognition of complications, and proper home management if discharge with a catheter.
  • When delivering enemas, follow strict safety steps, consider contraindications, control flow with bag height, monitor patient comfort, and limit repetitions as ordered.
  • Always document thoroughly: timing, volumes, patient tolerance, urine characteristics, and any deviations from standard procedure.