Complications and salvage options after laser lithotripsy for a vesical calculus in a tetraplegic patient: a case report

Safe Hb Concentration Measurement during Bladder Irrigation Using Artificial Intelligence

We have developed a sensor for monitoring the hemoglobin (Hb) concentration in the effluent of a continuous bladder irrigation. The Hb concentration measurement is based on light absorption within a fixed measuring distance. The light frequency used is selected so that both arterial and venous Hb are equally detected. The sensor allows the measurement of the Hb concentration up to a maximum value of 3.2 g/dL (equivalent to ≈20% blood concentration). Since bubble formation in the outflow tract cannot be avoided with current irrigation systems, a neural network is implemented that can robustly detect air bubbles within the measurement section. The network considers both optical and temporal features and is able to effectively safeguard the measurement process. The sensor supports the use of different irrigants (salt and electrolyte-free solutions) as well as measurement through glass shielding. The sensor can be used in a non-invasive way with current irrigation systems. The sensor is positively tested in a clinical study.

Endoscopic intact removal of medium-size- or multiple bladder stones with the use of transvesical laparoendoscopic single-site surgery

Objectives

To determine the feasibility and safety of performing transvesical laparoendoscopic single-site surgery (T-LESS) in patients with medium-size, hard stones or multiple stones with high burden.

Methods

In this case series study, 12 patients (11 males and one female) with a mean age of 66.8 years were operated on from February 2016 to May 2017 due to bladder calculi, using the T-LESS approach with a single-port device (Tri-Port + , Olympus, Germany). Indications for this procedure were hard, medium-size, solitary stones after previous unsuccessful endoscopic lithotripsy or the presence of multiple high-burden stones. In two patients, additional procedures (diverticulectomy or a ureterocele incision) were performed simultaneously.

Results

All stones were removed intact. No serious complications were observed. The mean operative time was 46 min and the postoperative hospital stay was 22 h. The mean diameter of the largest stone and the mean stone volume of each case were 24 mm and 11 cm³, respectively. At the mean follow-up time of 15 months, there was significant improvement of the symptoms.

Conclusions

The T-LESS technique is an efficient, safe and minimally invasive procedure for intact bladder stone removal in selected patients. The method avoids the risk of urethral injury. Nevertheless, further investigation is needed to assess the wider applicability of the procedure.