Stone Disease During Pregnancy: A Panel Discussion

Educational Objectives

The goals of this program are to improve treatment of stone disease during pregnancy. After hearing and assimilating this program, the clinician will be better able to manage a patient with a urinary tract stone during pregnancy while minimizing radiation exposure to the fetus.

Summary

Dr. Monga: patient with pain at 28 wk has hydronephrosis, distal stone, and right posterior acoustic shadowing; after 4 days of treatment in hospital, still has severe right flank pain, unrelenting nausea and vomiting, and no relief with narcotics; serum creatinine and white blood cell (WBC) count normal; urine shows stone fragments; urine culture negative; management depends on trimester; in this patient, first step conservative management; would α–blocker or nonsteroidal anti-inflammatory drug (NSAID) help?

Dr. Knudsen: α–blocker not usually prescribed in pregnancy

Dr. Monga: α–blockers not well-studied in pregnancy but sometimes used for eclampsia; inform patient that tamsulosin (Flomax) not approved during pregnancy; avoid NSAIDs due to detrimental effects on fetus; what imaging recommended if iterative reconstruction not available?

Dr. Eisner: repeat US; patients may experience bout of pain while expelling stone; no other imaging necessary; if presence of stone not clear on US but hydronephrosis present, do film of kidneys, ureters, and bladder (KUB); radiation from KUB equivalent to airplane flight; low-dose computed tomography (CT) acceptable if likely to change clinical management

Dr. Donovan: next step placement of stent; no radiographic studies needed before placing stent; limited retrograde urography can identify level of obstruction; do second urography after placement to verify position of stent

Dr. Monga: manage based on patient’s symptoms; most stones pass spontaneously without intervention, but this patient needs treatment; more imaging may not change management; having definitive diagnosis before surgery ideal, but must balance risks from radiation with risks of surgical intervention

Dr. Donovan: for this patient, forgo scout film; inject 5 mL contrast to determine level of stone and verify position of wire and stent; in third trimester, may change stent postpartum; length of stent based on height of patient

Dr. Knudsen: for documented stone, treat ureteroscopically; if stone suspected, perform KUB; if stone removed, can forgo stent; if no stone identified ureteroscopically, place stent; can place Sensor wire with little or no fluoroscopy; if imaging needed, use low-dose, pulsed beam, coned down over kidney; ensure coil of stent in kidney; may use US to guide procedures; if no stone found, need not check kidney with flexible ureteroscope unless US suggests renal stone; conflicting evidence on shielding uterus; shielding with automatic brightness control (ABC) might increase dose of radiation

Dr. Eisner: stent in second or third trimester may produce intolerable frequency; ureteroscopy safe; to minimize radiation, place nephrostomy tube under ultrasonic guidance; to treat stone, do ureteroscopy

Dr. Knudsen: no absolute size limit on stones approached by ureteroscopy unless staghorn morphometry

Dr. Donovan: in first trimester, do percutaneous nephrostomy under ultrasonic guidance; change tube every 6 to 8 wk

Dr Eisner: important to change tubes to avoid encrustation; change stents every 6 wk

Follow-up: patient underwent ureteroscopy with fluoroscopy and pelvic shielding; pulse mode and fixed settings used to decrease radiation; <3 seconds of fluoroscopy time needed to verify wire and stent coil; stent removed in 72 hr with dangler; patient had normal delivery at 40 wk

Physiology: most renal colic occurs in later trimesters; incidence not increased during pregnancy; most stones ureteral; sequelae of renal colic include infection, obstruction, and premature labor; during pregnancy, 90% of patients develop hydronephrosis, but most asymptomatic; pregnancy associated with increases in glomerular filtration rate and urine volume

Imaging: MRI safer than radiation but not helpful in pregnancy; low-dose CT not typically used; per American Congress of Obstetricians and Gynecologists, exposure to radiation primarily important in first trimester; <5 rad not associated with pregnancy loss or fetal anomalies; exposure from pelvic CT ≈3.5 rad, and concern for radiation should not prevent necessary diagnostic procedures; CT — low-dose protocols and adjustments to pitch and other parameters can decrease exposure to 700 mrad; most stone disease requires no intervention; waiting longer may result in fewer scans

Ureteroscopy: in meta-analysis of 116 procedures, stone removed with basket in one-half and lithotripsy in others; complete clearance of stones achieved in 86%; counsel patients about risk for premature labor

Shielding: if ABC catches edge of lead apron, scanner increases amount of exposure in response; use of ABC also results in increased exposure during retrograde pyelography, cystography or other procedure that uses contrast; use fixed settings during pregnancy

Conclusions: ureteroscopy more invasive than stent, but sometimes more effective; must individualize approach and consider morbidity associated with nephrostomy tubes and ureteral stents, eg, risk for encrustation; longer stent often required in pregnancy; multilength stent often preferable to sized stent; leave dangler when placing stent

Readings

Altman D et al: Anterior colporrhaphy versus transvaginal mesh for pelvic-organ prolapse. N Engl J Med 2011;364(19):1826-36; Barber MD et al: Accuracy of clinical assessment of paravaginal defects in women with anterior vaginal wall prolapse. Am J Obstet Gynecol 1999;181(1):87-90; Bot-Robin V et al: Use of vaginal mesh for pelvic organ prolapse repair: a literature review. Gynecol Surg 2012;9(1):3-15; Gandhi S et al: A prospective randomized trial using solvent dehydrated fascia lata for the prevention of recurrent anterior vaginal wall prolapse. Am J Obstet Gynecol 2005;192(5):1649-54; Grgic O et al: Outcome and efficacy of a transobturator polypropylene mesh kit in the treatment of anterior pelvic organ prolapse. Int J Gynaecol Obstet 2012;116(1):72-5; Guerette NL et al: Anterior repair with or without collagen matrix reinforcement: a randomized controlled trial. Obstet Gynecol 2009;114(1):59-65; Hefni M et al: Long-term quality of life and patient satisfaction following anterior vaginal mesh repair for cystocele. Arch Gynecol Obstet 2013;287(3):441-6; Herz D et al: Dysfunctional elimination syndrome as an etiology of idiopathic urethritis in childhood. J Urol 2005;173(6):2132-7; Hoşcan MB et al: Management of symptomatic ureteral calculi complicating pregnancy. Urology 2012;80(5):1011-4; Iglesia CB et al: Vaginal mesh for prolapse: a randomized controlled trial. Obstet Gynecol 2010;116(2 Pt 1):293-303; Johnson EB et al: Obstetric complications of ureteroscopy during pregnancy. J Urol 2012;188(1):151-4; Laing KA et al: Outcomes of ureteroscopy for stone disease in pregnancy: results from a systematic review of the literature. Urol Int 2012;89(4):380-6; Liang R et al: Vaginal degeneration following implantation of synthetic mesh with increased stiffness. BJOG 2013;120(2):233-43; Maher C et al: Surgical management of pelvic organ prolapse in women. Cochrane Database Syst Rev 2013;4:CD004014; Masselli G et al: Imaging of stone disease in pregnancy. Abdom Imaging 2013 Jun 16 [Epub ahead of print]; Petrou SP et al: Dorsal vaginal graft urethroplasty for female urethral stricture disease. BJU Int 2012;110(11 Pt C):E1090-5; Singla P et al: Imaging of the female urethral diverticulum. Clin Radiol 2013;68(7):e418-25; Vollebregt A et al: Primary surgical repair of anterior vaginal prolapse: a randomised trial comparing anatomical and functional outcome between anterior colporrhaphy and trocar-guided transobturator anterior mesh. BJOG 2011;118(12):1518-27; White WM et al: Low-dose computed tomography for the evaluation of flank pain in the pregnant population. J Endourol 2007;21(11):1255-60; Whiteside JL et al: Clinical evaluation of anterior vaginal wall support defects: interexaminer and intraexaminer reliability. Am J Obstet Gynecol 2004;191(1):100-4; Withagen MI et al: Trocar-guided mesh compared with conventional vaginal repair in recurrent prolapse: a randomized controlled trial. Obstet Gynecol 2011;117(2 Pt 1):242-50.

Disclosures

In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the planning committee to disclose relevant financial relationships within the past 12 months that might create any personal conflicts of interest. Any identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business or commercial interest. For this program, the following has been disclosed: Dr. Eisner is a consultant for Boston Scientific, Olympus/Gyrus ACMI, and PerSys Medical; and receives financial support (the nature of which is unspecified) from Ravine Group. Dr. Knudsen is a consultant for Boston Scientific. Drs. Monga and Donovan and the planning committee reported nothing to disclose.

Acknowledgements

p> Drs. Manoj, Donovan, Eisner, and Knudsen were recorded at the 2013 Annual Spring Meeting of the Ohio Urological Society, held March 15-16, 2013, in Sandusky, OH.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0 CE contact hours.

Lecture ID:

UR361702

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.

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