Safety and feasibility of percutaneous nephrolithotomy (PCNL) during pregnancy: A review of literature

Does type of anesthesia during procedural management of suspected renal colic during pregnancy have an impact on preterm birth?

INTRODUCTION

Anesthesia choice during the procedural management of suspected renal colic during pregnancy may vary based on available resources and patient or provider preferences, as there are no specific recommendations. Our objective was to evaluate whether preterm birth (<37 weeks) was associated with anesthesia type, anesthesia timing by trimester, or procedure type.

METHODS

We retrospectively identified pregnant patients who required procedural management with ureteral stent, percutaneous nephrostomy (PCN), or ureteroscopy (URS) for suspected renal colic based on laboratory and imaging findings from 2009-2021 at our center. Analyzed data included anesthesia type (local analgesia only, monitored anesthesia care [MAC], spinal anesthesia, or general anesthesia), trimester of procedure, procedure type, and obstetric outcomes, including preterm birth.

RESULTS

The study cohort included 96 patients who underwent 231 total procedures, including primary URS, PCN, and stent, as well as PCN and stent change. The median gestational age was 38.7 weeks (37.1-39.5), and preterm birth rate was 15.8%. The most common anesthetic used across all procedures and trimesters was MAC. PCN was associated with the use of less invasive analgesia or anesthesia, whereas endoscopic procedures were more commonly performed with spinal or general anesthesia. Using multivariable logistic regression, procedure type was associated with preterm birth, but not anesthesia type or timing by trimester.

CONCLUSIONS

Anesthesia type and timing were not associated with preterm birth, and selection may be influenced by resources, clinical scenario, or patient and provider preferences.

Conventional ultrasonography enabled with augmented reality needle guidance for percutaneous kidney access: an innovative methodologies randomized controlled trial

IMPORTANCE

Successful needle puncture of the renal collecting system is a critical but difficult procedure in percutaneous nephrolithotomy (PCNL). Although fluoroscopy and ultrasound are the standard imaging techniques to guide puncture during PCNL, both have known limitations.

OBJECTIVE

To assess the feasibility and safety of a new navigation system for needle puncture in ultrasound-guided PCNL.

DESIGN

This study employed a single-center randomized controlled trial (RCT) design to assess the feasibility and safety of a new navigation system for needle puncture in ultrasound-guided PCNL. Conducted between May 2021 and November 2021, the trial utilized computer-generated random numbers for participant allocation to control for selection bias.

SETTING

The trial was executed at Department of Urology, Peking University First Hospital in Beijing, China, which serves as an academic medical center.

PARTICIPANTS

All patients who met the inclusion criteria were randomly divided into two groups, with 29 patients in each group. One group underwent PCNL procedures using the new navigation system, while the control group underwent standard ultrasound-guided PCNL procedures. Included patients had renal pelvis or caliceal calculi larger than 2.0 cm in diameter or had multiple or staghorn stones. The puncture procedure was performed with the support of real-time ultrasound imaging and visual guidance displayed on the screen.

MAIN OUTCOMES AND MEASURES

The primary outcome was system feasibility and puncture success rate. Secondary outcomes included puncture time, total surgical time, number of attempts, postprocedure complications, and 1-year and 3-year stone recurrence rates. Stone clearance was defined by postoperative CT. Descriptive statistics summarized patient demographics, stone size, and location. Independent samples t -tests analyzed puncture time and total surgical time. χ2 or Fisher's exact tests compared stone clearance, complications, socioeconomic status, renal hydronephrosis, stone location, race, and medical history. Linear regression examined the correlation between BMI and puncture time. Significance was set at P <0.05.

RESULTS

For all 58 patients undergoing PCNL, needle punctures of the renal collecting system were completed with a success rate of 100%. The average time from planning the puncture protocol to successful puncture was significantly shorter in the AcuSee guidance system group (3.12 min, range 0.2-6.88 min) compared to the standard ultrasound-guided group (7.58 min, range 5.41-10.68 min), representing a reduction of ~59%. The total surgical time was also shorter in the AcuSee group for patients with no and mild hydronephrosis ( P <0.05). Complication rates were lower in the AcuSee group, with no major complications observed. However, three patients in the standard ultrasound-guided group have adverse effects after the PCNL procedure. The 1-year stone recurrence rate was significantly lower in the AcuSee group (3.4%) compared to the standard group (24.1%), and the 3-year recurrence rate was also lower (6.9% vs. 41.4%). Patient-specific factors such as BMI, renal morphology, and prior surgical history did not significantly affect the performance of the AcuSee system.

CONCLUSIONS AND RELEVANCE

The authors report the first clinical application of a new navigation system for needle puncture in ultrasound-guided PCNL. It has been demonstrated that it is feasible and safe compared to the standard ultrasound-guided group in percutaneous renal puncture. This technology provides intuitive and easy-to-use visual guidance, which may facilitate safe, accurate, and fast needle puncture of the kidney.

Navigating the Complexities of Symptomatic Hydronephrosis in Pregnancy

The management of symptomatic hydronephrosis presents substantial challenges due to the absence of consensus within clinical guidelines concerning pain management, diagnostic approaches, therapeutic interventions, and follow-up protocols. This literature review focuses on complexities involving diagnostic challenges that arise from the difficulty in distinguishing physiological from pathological obstruction and treatment complexities that involve deciding on the most appropriate pain management medications and safe interventions while minimizing risks to both the mother and foetus. To address these challenges, a comprehensive search of electronic databases, including PubMed, Embase, and Google Scholar, was conducted for the terms "hydronephrosis", "hydronephrosis in pregnancy", "ionising radiation in pregnancy", and "safe analgesia in pregnancy". Moreover, Mendeley software was used to collect and organize the references. Diagnostic complexities involve selecting the appropriate imaging modality that balances accurate diagnosis with minimal radiation to the foetus. Ultrasound remains the first-line option. However, it has limitations in delineating the underlying aetiology. MRI avoids ionizing radiation but has restricted utility due to foetal movement artifacts. CT provides the highest diagnostic accuracy but raises foetal radiation exposure concerns, though ultra-low dose protocols (<1 mGy) are deemed acceptable by most guidelines. Management includes either a conservative approach, which is a safe option in the majority of cases, or intervention with a percutaneous nephrostomy or ureteric stent insertion, both with comparable symptom control. However, there is no consensus on the optimal frequency for drain changes to prevent rapid encrustation. Definitive procedures like ureteroscopy and percutaneous nephrolithotomies remain controversial. Most guidelines suggest limiting these interventions to specialist centres during the second trimester if required.

Management of Kidney Stone Disease in Pregnancy: A Practical and Evidence-Based Approach

PURPOSE OF REVIEW

Suspected kidney stone disease during pregnancy is a difficult condition for health professionals to manage. This is partly due to the more limited range of diagnostic and therapeutic strategies, which can be safely applied. A comprehensive review of literature was performed to identify evidence to develop a practical guide to aid clinicians.

RECENT FINDINGS

Ultrasound remains the recommended first line option for imaging. Complicated cases, such as suspected infected obstructed system, require urgent decompression such as in the form of percutaneous nephrostomy. This article highlights the pharmacotherapeutic agents, which are considered safe for use in pregnancy. Where surgical intervention is indicated, evidence supports ureteroscopy to be a safe option as long as infection has been treated. Ureteroscopy can offer definitive clearance of the stone(s) and can be less burdensome regarding bothersome symptoms compared to indwelling ureteral stent or nephrostomy, which also require regular exchange due to the high propensity for encrustation in pregnancy. A multidisciplinary approach is fundamental to safely manage suspected kidney stone disease in pregnancy. Adoption of a locally agreed pathway as suggested in this article supports improved patient care.