A ten-year, single institution experience with percutaneous nephrostomy during pregnancy

Comparison of Radiation Exposure for Pregnant Patients Requiring Intervention for Suspected Obstructing Nephrolithiasis

OBJECTIVE

To identify the differences in radiation exposure per suspected stone episode between percutaneous nephrostomy tube (PCN), stent, and primary ureteroscopy (URS).The incidence of nephrolithiasis in pregnancy is low; however, repercussions for both mother and fetus can be significant. In cases of suspected obstructing nephrolithiasis, intervention may be required, including ureteral stent, PCN, or URS, with the potential for multiple subsequent procedures that often utilize fluoroscopy.

METHODS

Pregnant patients who required an intervention (stent, PCN, or URS) for suspected obstructing nephrolithiasis were retrospectively reviewed. The primary outcome was total fluoroscopy exposure per suspected stone episode. Secondary outcomes included fluoroscopic exposure per procedure and number of procedures required.

RESULTS

After excluding patients with renal anomalies and incomplete radiation data, 78 out of 100 patients were included in the analysis. Forty patients (51.3%) underwent initial stent placement, 22 (28.2%) underwent initial PCN placement, and 16 (20.5%) underwent primary URS. Total mean radiation exposure per stone episode was significantly higher in patients who underwent PCN, (286.9 mGy vs 3.7 mGy (stent) and 0.2 mGy (URS), P <.001). In addition, patients who underwent initial PCN placement had significantly more procedures (P <.001) and mean radiation exposure per procedure was higher (P <.001). More than 40% of PCNs experienced dysfunction, and mean duration between PCN exchanges was 16.5 days.

CONCLUSION

In pregnant patients with suspected obstructing nephrolithiasis requiring intervention, initial PCN placement was associated with a significantly higher number of procedures, radiation exposure per procedure, and total radiation exposure per suspected stone episode compared to stent and URS.

Interventional Radiology and Pregnancy: From Conception through Delivery and Beyond

Interventional radiology (IR) plays a unique and often invaluable role in the care of pregnant patients. Special considerations regarding radiation exposure and medication choice must be taken into account when evaluating a pregnant patient for an interventional procedure. In addition, the physiologic changes that occur during pregnancy can pose special challenges for an interventionalist when treating this patient population and should be appropriately recognized. Still, the majority of standard IR procedures can be safely performed in the pregnant population, often with additional precautions and proper patient education about the risks, benefits, and alternatives. In many cases, interventional radiologists can provide lifesaving and fertility-preserving alternatives to more invasive surgical intervention. The authors summarize radiation exposure effects and guidelines and medication choice during pregnancy. The physiologic changes that occur during pregnancy are discussed, with specific interest in the pathologic consequences that can be treated with IR. The authors also describe a wide variety of minimally invasive image-guided procedures offered by IR in pregnant, peripartum, or postpartum patients. The areas where IR can help in the treatment of pregnant patients include venous access, biopsies, genitourinary and biliary interventions, venous thromboembolism treatments, ectopic pregnancy management, aneurysm intervention, and management of trauma patients. IR is also involved in management during the peripartum or postpartum periods, with roles in treatment of invasive placenta spectrum, postpartum hemorrhage after vaginal delivery, and postcesarean delivery complications. ©RSNA, 2023 Supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

Management of urolithiasis in pregnancy

Urolithiasis is the most common cause of nonobstetric abdominal pain, resulting in 1.7 admissions per 1000 deliveries. Urolithiasis most commonly occurs in the second and third trimesters, with an incidence between 1:125 and 1:2000. Acute urinary system obstructions are challenging to manage in obstetric patients because they contribute to physiological and anatomical changes that result in pathological outcomes. The restricted use of computed tomography in diagnosing and managing urolithiasis is particularly challenging. In addition, a prompt diagnosis is required because the presence of renal calculi during pregnancy increases the risk of fulminating sepsis and preterm delivery. Affected pregnancies are conservatively managed; however, 1 in 4 requires surgical intervention. Indications for surgical interventions are complex and range from nephrostomy insertion to empirical stent placement or ureteroscopy. Therefore, a multidisciplinary approach is required to optimize patient care. The diagnosis and management of urolithiasis in pregnancy are complex. We reviewed the role, safety, advantages and disadvantages of diagnostic tests and treatment used to manage acute urinary obstructions in pregnancy.

New clinic workflow improves compliance for routine PCN exchanges

PURPOSE

To examine the effect of a clinic workflow intervention on follow-up for routine ercutaneous nephrostomy tube (PCN) exchanges.

METHODS

An intervention consisting of automated electronic tracking for all PCN placements and exchanges followed by phone call reminders to schedule a follow-up exchange 60 days post-procedure was introduced on March 19, 2019. All PCN exchanges performed from March 19, 2018 to September 18, 2019 were identified through a local electronic database search to assess the impact of intervention as a quality improvement project. Basic demographic information and procedure details were collected. Routine follow-up at our institution is recommended every 90 days. The exchange rates within 90 days were compared between groups using a Chi-squared test.

RESULTS

A total of 160 PCN placements or exchanges were performed pre-intervention and 69 PCN exchanges were performed post-intervention. Pre-intervention, 75/160 (46.3%) were exchanged within 90 days compared to 47/69 (68.1%) exchanged within 90 days post-intervention. The remainder had delayed follow-up due to loss to follow-up or scheduling delays. Post-intervention, there was a significantly improved rate of compliance for PCN exchanges within the recommended 90 days at our institution (p-value = 0.002).

CONCLUSION

Automated tracking and phone call follow-up at 60 days post-procedure is a simple and effective intervention that can improve compliance for routine PCN exchanges and reduce the number of patients that are lost to follow-up.

Rethinking Time-to-Exchange: Outcomes of Nephrostomy Tube Placement in Pregnancy

This study evaluated outcomes for percutaneous nephrostomy tube placement in pregnant patients, including potential complications that required early, unplanned tube exchange. A retrospective review was conducted for 51 pregnant patients and a nonpregnant cohort matched 1:1 who received percutaneous nephrostomy tube placement between 2012 and 2020. Factors potentially contributing to unplanned tube exchanges were analyzed, including gestational age, prevalence and severity of hydronephrosis, presence of renal calculi, and serum calcium level. The mean tube exchange interval was significantly shorter in the pregnant group (3.4 weeks ± 1.8 [standard deviation] vs 5.7 weeks ± 0.7, P < .0001), and pregnant subjects were significantly more likely to require reintervention before the 6-week scheduled exchange (80.4% vs 21.6%, P < .0001). The serum calcium level was lower in pregnant subjects (8.4 mg/dL ± 0.4 vs 8.9 mg/dL ± 0.7, P = .002). A shorter interval schedule (every 3 weeks) of routine percutaneous nephrostomy tube exchange in pregnant patients may be necessary to avoid complications.