What is the recommended post-removal care for a Lumen-Apposing Metal Stent (LAMS) with Endoscopic Ultrasonography (EUS)-guided cystogastrostomy, including duration of Nil Per Os (NPO) and need for prophylactic antibiotics?

Post-LAMS Removal Management After EUS-Guided Cystogastrostomy

After LAMS removal following EUS-guided cystogastrostomy, prophylactic antibiotics should be continued post-procedurally, though specific NPO duration is not well-defined in guidelines; however, based on standard endoscopic practice, patients can typically resume oral intake within hours if no complications occur, with simultaneous exchange to double pigtail plastic stents at the time of LAMS removal to maintain fistula patency. 1, 2

Prophylactic Antibiotic Management

Antibiotics should be continued after LAMS removal. 1 The Asian EUS Group consensus guidelines explicitly state that prophylactic antibiotics are recommended and should be continued post-procedurally, though no specific duration is provided. 1 The rationale is that by creating a cystogastrostomy, you are converting a clean system to a clean-contaminated environment. 1

• Continue prophylactic antibiotics covering enteric gram-negative organisms and enterococci during the post-removal period. 2
• While the exact duration is not specified in guidelines, standard practice suggests continuing antibiotics for 24-48 hours post-procedure based on similar interventional endoscopic procedures. 3

NPO Duration Post-LAMS Removal

The guidelines do not provide specific NPO duration after LAMS removal. However, based on the nature of the procedure:

• Since LAMS removal is typically performed during routine follow-up endoscopy at 4-6 weeks with simultaneous stent exchange (not initial placement), this is a less traumatic intervention than the original drainage procedure. 2
• Standard endoscopic practice would suggest NPO for 2-4 hours post-procedure if no complications occur, then advance diet as tolerated. 3
• If there are concerns about the fistula tract integrity or if significant manipulation occurred, extending NPO to 6-8 hours would be prudent.

Timing of LAMS Removal

Remove the LAMS within 4-6 weeks after initial placement once the collection has resolved. 2 This timing allows adequate fistula tract maturation while minimizing stent-related complications including food impaction, buried stent syndrome, and delayed bleeding. 1, 2

Critical Step: Simultaneous Stent Exchange

At the time of LAMS removal, simultaneously exchange to double pigtail plastic stents to maintain the cystogastrostomy tract. 2 This is the most important aspect of post-LAMS management:

• Place one or two 7 Fr double pigtail plastic stents through the established fistula tract at the time of LAMS removal. 2
• This prevents fistula closure and reduces recurrent collection formation from 20% (without stent maintenance) to 2.6% (with proper stent maintenance). 2
• Technical success rate of this exchange approach is 93.1%. 1, 2

Follow-Up Protocol

Perform routine follow-up endoscopy at 4-6 weeks after initial drainage to assess for: 2

• Complete clearance of any residual necrotic debris (spontaneous passage occurs in approximately 56% of cases). 1, 2
• Patency of the fistula tract
• Need for additional interventions or debridement using stone-retrieval baskets if residual solid material persists. 2

Plastic Stent Maintenance

Maintain plastic stents with routine exchanges every 2-4 weeks until the cavity has contracted to <2 cm in size. 2 This ensures sustained drainage and prevents premature fistula closure.

Alternative Approach for High-Risk Patients

In frail patients or those refusing a second procedure, the LAMS may be left in place permanently with acceptable outcomes: 1, 2

• 3-year stent patency of 86%
• Delayed adverse events occurring in only 7.1% of cases
• This avoids the need for stent exchange but requires acceptance of long-term LAMS presence

Common Pitfalls to Avoid

Removing LAMS without simultaneous plastic stent placement leads to fistula closure and recurrent collection in 20% of cases. 2

Leaving LAMS in place beyond 4-6 weeks increases risk of: 1, 2

• Food impaction
• Buried stent syndrome
• Delayed bleeding from pseudoaneurysm formation (rare but potentially fatal complication). 4

Inadequate antibiotic coverage during the post-removal period when the tract remains a clean-contaminated environment. 1, 2