Is postoperative Doppler ultrasonography useful for the early detection of asymptomatic pseudoaneurysm and prevention of haemorrhagic complications after partial nephrectomy?

Natural history of asymptomatic renal artery pseudoaneurysm after robot-assisted partial nephrectomy

Background

We assessed the natural history of renal artery pseudoaneurysm (RAP) after robot-assisted partial nephrectomy (RAPN).

Methods

From May 2016 to September 2020, 106 patients underwent RAPN for renal tumors at our institution. Among 100 patients, excluding 6 who were ineligible for contrast-enhanced computed tomography (CE-CT), 4 underwent renal artery selective embolization (RAE), of which 2 cases were emergency RAE within 7 days after RAPN and the other 2 were prophylactic RAE 8 or more days after RAPN. In 98 patients examined for the clinical course of asymptomatic RAP managed by surveillance, excluding the 2 who underwent emergency RAE, routine CE-CT was performed at 7 days, 1 month and 3 months after RAPN. Factors influencing the occurrence of RAP among these 98 patients, including the 2 who underwent emergency RAE and excluding the 2 who underwent prophylactic RAE, were analyzed by logistic regression analysis.

Results

Median [interquartile range (IOR), range] observation period, age, radiographic tumor size, and maximum diameter of RAP were 20.8 (23.9, 3.0–57.6) months, 63 (18, 22–84) years, 23 (11, 9–48) mm, and 6.6 (5.2, 3.0–16.0) mm, respectively. CE-CT detected 28 RAPs in 23 (23.0%) of 100 patients by 7 days after RAPN and routine CE-CT detected 25 RAPs in 21 (21.4%) of 98 patients excluding 2 who underwent emergency RAE at 7 days after RAPN. RAP was diagnosed by routine CE-CT in 21 (21.4%), 1 (1.0%), and 0 (0%) patients at 7 days, 1 month, and 3 months after RAPN, respectively. In univariate analysis, age [odds ratio (OR) 0.144: 69–84 vs. 22–56 years old, P=0.0179], R.E.N.A.L [radius (tumor size as maximal diameter), exophytic/endophytic properties of tumor, nearness of tumor deepest portion to collecting system or sinus, anterior/posterior descriptor and location relative to polar line] nephrometry score (OR 1.374, P=0.0382), warm ischemic time (OR 1.085, P=0.0393), and renorrhaphy time (OR 1.055, P=0.0408) were significantly associated with the occurrence of RAP. In multivariate analysis, only age (OR 0.124, P=0.0148) was a significant factor.

Conclusions

Asymptomatic RAP up to 15 mm in diameter resolved spontaneously 3 months after RAPN. Young age (under 56 years) may be a factor in the development of RAP.

Open partial nephrectomy: current review

Partial nephrectomy (PN) is increasingly considered the gold standard treatment for localized renal cell carcinomas (RCCs) where technically feasible. The advantage of nephron-sparing surgery lies in preservation of parenchyma and hence renal function. However, this advantage is counterbalanced with increased surgical risk. In recent years with the popularization of minimally invasive partial nephrectomy (laparoscopic and robotic), the contemporary role of open PN (OPN) has changed. OPN has several advantages, particularly in complex patients such as those with a solitary kidney, multi-focal tumors, and significant surgical history, as well as providing improved application of renoprotective measures. As such, it is a technique that remains relevant in current urology practice. In this article we discuss the evidence, indications, operative considerations and surgical technique, along with the role of OPN in contemporary nephron-sparing surgery.

Natural History of Asymptomatic Pseudoaneurysm Soon After Robot-assisted Partial Nephrectomy: Single-center Prospective Study

OBJECTIVE

To prospectively investigate the natural history of asymptomatic pseudoaneurysm after robotic-assisted partial nephrectomy.

METHODS

Robotic-assisted partial nephrectomy was undertaken for 67 patients between July 2014 and July 2018. Patients who could not undergo enhanced CT were excluded, so 60 patients were finally included in the present study. We prospectively investigated the presence of pseudoaneurysm based on early enhanced CT scan on postoperative day 7. According to our treatment policy, patients with symptomatic pseudoaneurysm underwent selective transarterial embolization. Meanwhile, patients with asymptomatic pseudoaneurysm were observed with follow-up CT imaging, regardless of the size of the aneurysm.

RESULTS

Overall incidence of pseudoaneurysm on postoperative day 7 was 18% (11/60 cases). The median size of the pseudoaneurysm was 9 mm (quartile: 6-12 mm). Two patients with symptomatic pseudoaneurysm underwent selective transarterial embolization. Nine patients had asymptomatic pseudoaneurysm; in 8 of these it disappeared without therapeutic intervention. The median period from surgery to confirmed disappearance of the aneurysm was 19 days (quartile 14-32 days). In the remaining 1 patient, small asymptomatic pseudoaneurysm (2 mm) could still be observed even 1 year after surgery.

CONCLUSION

Our study showed high incidence of pseudoaneurysm 1 week after robotic-assisted partial nephrectomy that mostly disappeared without therapeutic intervention. Routine enhanced CT screening and pre-emptive embolization may not be necessary for asymptomatic renal artery pseudoaneurysm.

Lessons learned from clinical outcome and tumor features of patients underwent selective artery embolization due to postoperative bleeding following 2076 partial nephrectomies: propensity scoring matched study

PURPOSE

To evaluate the clinical and tumor characteristics in patients undergoing selective artery embolization (SAE) for bleeding after partial nephrectomy (PN).

METHODS

We retrospectively evaluated patients who underwent SAE from 2076 patients who underwent PN. The clinical and tumor characteristics of these patients were analyzed using entire data and propensity score matching (PSM). 76 patients who underwent PN (control, n = 38 patients; SAE, n = 38) were enrolled in PSM.

RESULTS

SAE was performed in 41 patients who underwent open (19/1171), laparoscopic (4/60), and robot-assisted PN (18/845). The median period from PN to SAE was 12 days (interquartile range 8-24 day). The most common symptom of 31 (75.61%) patients was gross hematuria, followed by flank pain (3/41). Follow-up imaging revealed large pseudoaneurysm in 7 asymptomatic patients. The main reason for SAE on angiography was pseudoaneurysm (32/41), followed by arteriovenous fistula (5/41). Technical and clinical success was achieved in all patients. There was no statistical difference in the estimated glomerular filtration rate after 1 year, surgical methods, or baseline characteristics between the two groups. Conversely, there was statistically significant difference in ischemic time in the entire data and PSM. In the embolization group, renal masses showed statistically significant endophytic (p = 0.006) and posterior (p = 0.028) characteristics.

CONCLUSIONS

SAE is an effective method for controlling postoperative bleeding while preserving renal function after PN. And, we suggest more attentive postoperative surveillance about vascular complications in patients with longer ischemia time or renal masses with endophytic and posterior locations.