It is common for a urinary catheter to be inserted during back surgery procedures that involve the lower spine. A catheter provides a way to drain urine from the bladder and monitor urine output during and after surgery. This helps avoid bladder distention and urinary retention, which could impede healing or cause complications. The catheter is usually removed within a day or two after surgery once the patient can walk to the bathroom.
Why a Catheter is Used
There are a few key reasons a urinary catheter may be placed for back surgery:
- To monitor urine output: After surgery, it’s important to monitor how much urine the patient is producing as it indicates kidney function. Low urine output could signal dehydration or other problems. The catheter provides an easy way to measure this.
- To prevent bladder over-distention: Anesthesia, pain medication, and prolonged immobility during and after surgery can slow signals that trigger urination. The catheter provides passive drainage to keep the bladder from overfilling.
- To bypass urinary retention: Spinal anesthesia and surgery effects may make it difficult or impossible to urinate normally for a period of time. The catheter provides a temporary way to empty the bladder until normal urination returns.
Without a catheter, the bladder may become distended, risking permanent injury and upstream kidney damage. Catheter use avoids this scenario.
When a Catheter May Be Used
For upper back procedures like cervical spinal fusion, a urinary catheter is not always necessary since there is minimal impact on urinary function.
However for middle to lower back surgeries, including:
- Lumbar spinal fusion
- Spinal stenosis surgery
Surgeons will often make the decision to insert a urinary catheter as a precautionary measure. This is because the spine controls the nerve signals involved in urination. Interrupting these pathways can make urinating normally difficult, at least temporarily.
Some specific scenarios where a catheter is more likely to be used include:
- Long surgeries over several hours in length
- Surgeries where severe nerve compression is being corrected
- Cases where spinal cord monitoring electrodes are placed
- When epidural anesthesia is being administered
The catheter may be avoided for shorter, minimally invasive back procedures where urinary function is less likely to be significantly impaired.
The Catheter Insertion Process
The urinary catheter is inserted after the patient is under anesthesia, just prior to the start of the back surgery. The process involves these general steps:
- The patient is positioned on their back and the genital region is cleaned with an antiseptic solution.
- Using sterile gloves, the catheter tube is advanced through the urethral opening and into the bladder.
- Once urine flow begins through the catheter, it is connected to a drainage bag to collect urine.
- The catheter bag is situated below the level of the bladder to facilitate gravity drainage.
- Urine output will be monitored by recording the amount that accumulates in the drainage bag.
An anesthesiologist, urologist, or surgical nurse handles catheter insertion and setup, taking care to use sterile technique. This minimizes the risk of introducing bacteria that could lead to a urinary tract infection.
Lubricant gel is always used to allow smooth catheter insertion. For men, the penis may be held perpendicular to the body to straighten the urethra and allow easier insertion.
Catheter Care After Surgery
Once surgery is completed, the urinary catheter will remain in place until bladder and urinary function recover enough to remove it. This is typically 24-48 hours but may be longer if there are complications.
While the catheter is dwelling, care steps include:
- Keeping the catheter secured to prevent dislodgment
- Keeping the system closed and sterile to prevent infection
- Observing urine output
- Routine catheter irrigation if needed to prevent obstruction
The patient may have some bladder cramping or discomfort as long as the catheter is inserted. Skin irritation can also occur.
The drainage bag will need to be emptied periodically according to the urine output. A night bag system may be set up to allow continuous drainage at night.
Once the bladder recovers and any urine retention resolves, the catheter can be removed. This involves gently pulling the catheter out through the urethral opening. A small amount of discomfort or stinging may be felt.
While catheter use prevents complications from bladder distention and overflow, the catheter itself does introduce some risks including:
- Urinary tract infections: Bacteria can be introduced into the urinary tract during catheter insertion or dwell time, leading to infection.
- Urethral injury: Improper catheter insertion technique can cause damage to the delicate urethral tissues.
- Catheter blockage: Blood clots or sediment can obstruct the catheter drainage leading to leakage.
- Bladder spasms: Some patients experience painful bladder cramping and spasms from catheter irritation.
To minimize complications, catheters are used only when needed and removed as soon as appropriate. Proper catheter care is provided throughout dwell time. Patients are monitored for signs of infection.
In summary, urinary catheter insertion is performed routinely for many lumbar and lower spinal surgeries to facilitate monitoring of urine output and prevent bladder overdistention. The catheter is placed once anesthesia is administered and typically removed 1-2 days post-op once bladder function recovers. While catheters have associated risks, the benefits often outweigh these in major back surgery where urination may be impaired. With proper precautions and care, catheters can be used safely to optimize surgical outcomes. Patients should discuss any concerns about catheter use with their surgical team prior to the procedure.