What are the guidelines for combining catherization and spinal anesthesia in patients?

Catheterization and Spinal Anesthesia

Routine indwelling urinary catheterization is not necessary for most patients undergoing procedures with spinal anesthesia, and selective catheterization based on bladder volume monitoring reduces urinary tract infections while maintaining safety. 1, 2

Evidence-Based Approach to Catheterization Decision

When to Avoid Routine Catheterization

• Patients undergoing procedures under spinal anesthesia with anticipated duration <4 hours do not require routine indwelling catheters, as urinary retention rates are low (approximately 30%) and can be managed with intermittent catheterization if needed 1, 3, 4

• Routine indwelling catheterization increases urinary tract infection risk (1.4% vs 0.0% without catheter) without reducing major postoperative urinary retention 2

• Younger patients (18-40 years) undergoing minor surgery with long-acting spinal anesthetics and receiving <800 mL intraoperative fluids have very low retention rates (2.5%), making routine catheterization unnecessary 4

Bladder Volume Monitoring Protocol

Use ultrasound bladder scanning (Bladderscan) instead of routine catheterization to guide selective intervention: 3

• Measure bladder volume preoperatively and at end of surgery 3
• If postoperative bladder volume >300 mL, perform catheterization in the operating room (6.5-fold increased risk of retention) 3
• If bladder volume <300 mL at surgery end, transfer to recovery and monitor every 60 minutes for maximum 3 hours or until spontaneous voiding occurs 3
• Catheterize if bladder volume exceeds 500 mL or after two failed attempts at spontaneous voiding 3, 2

Procedure-Specific Considerations

For total hip arthroplasty under spinal anesthesia: 1, 2

• No routine catheter needed—only 4.5% develop major retention requiring indwelling catheter 1
• Allow up to two straight catheterizations before placing indwelling catheter 1, 2
• Minor retention (5-10%) resolves with 1-2 straight catheterizations 2

For arthroscopic knee surgery with low-dose spinal (1.4 mL 0.5% bupivacaine): 3

• 70% void spontaneously without intervention 3
• Bladder volume monitoring superior to routine catheterization 3

For complex pediatric urological procedures: 5

• Combined spinal/caudal catheter technique allows extended procedures (average 109 minutes, range 63-172 minutes) without general anesthesia or routine urinary catheterization 5

Spinal Anesthesia Technique Considerations

Neuraxial Catheter Placement Timing

Consider early insertion of neuraxial catheters (epidural or combined spinal-epidural) for high-risk patients to avoid general anesthesia if emergent procedures become necessary: 6

• Obstetric indications: twin gestation, preeclampsia 6
• Anesthetic indications: anticipated difficult airway, obesity 6
• Catheter insertion may precede labor onset or analgesia request 6

Combined Spinal-Epidural (CSE) Advantages

CSE provides faster onset than epidural alone (approximately 7 minutes faster) with superior reliability because successful spinal flow confirms correct epidural placement: 7

• Use pencil-point (atraumatic) needles instead of cutting-bevel needles to minimize post-dural puncture headache risk 6, 7
• Combine low-dose local anesthetic with opioid for both components to minimize motor block 6, 7
• Use dilute local anesthetic concentrations (bupivacaine 0.1-0.125%) with opioids for epidural maintenance 6, 7

Single-Shot Spinal Limitations

If labor or procedure duration exceeds anticipated analgesic effects of spinal drugs, or if operative delivery is reasonably possible, use catheter technique instead of single-injection: 6

• Single-injection spinal provides time-limited analgesia only 6
• Adding local anesthetic to spinal opioid increases duration and quality 6

Critical Pitfalls to Avoid

• Do not routinely catheterize all spinal anesthesia patients—this increases infection risk without benefit 2, 4
• Do not ignore bladder volume >300 mL postoperatively—this significantly increases retention risk requiring intervention 3
• Do not delay spinal anesthesia to administer fixed IV fluid volumes—fluid preloading/coloading may reduce hypotension but should not delay procedure 6
• Do not use cutting-bevel spinal needles—pencil-point needles significantly reduce post-dural puncture headache 6, 7

Monitoring Requirements

Equipment, facilities, and support personnel must be immediately available to treat complications including hypotension, respiratory depression, and local anesthetic systemic toxicity: 6, 7

• Have vasopressors (phenylephrine or ephedrine) ready for hypotension management 6
• Monitor temperature to prevent hypothermia (occurs in 50-80% of spinal anesthesia patients) 6
• Use forced air warming, IV fluid warming, and increased operating room temperature 6