Pediatric Robotic Pyeloplasty

Fig. 29.1

Operating room setup for right robotic pyeloplasty demonstrating standard configuration of operating room personnel and equipment

Fig. 29.2

Operating room setup for left robotic pyeloplasty demonstrating standard configuration of operating room personnel and equipment

Patient Positioning and Preparation

Initially, place the patient in lithotomy or frog-legged position for retrograde ureteral stent (if planned) and urethral catheter placement. Next, place the patient in modified flank with a 30° wedge under the ipsilateral side where the pyeloplasty will be performed with padding and tape across chest and thighs. Folded towels and tape are placed over the patient’s arms but under the abdomen (Fig. 29.3). If an antegrade stent placement is planned, we will prep in the penis in males and prep in a pre-placed council catheter in females. Flexible cystoscopy with a pediatric flexible cystoscope or ureteroscope can then be performed to confirm stent position, in females using a wire to gain access to bladder can make the process faster. Rotate the table so that the patient’s abdomen is flat while obtaining trocar access, then rotate to 60° (30° wedge plus 30° table rotation) just prior to docking the robot. The anesthesia team should place an NG or OG tube before access.

Fig. 29.3

Patient positioning shown for a left pyeloplasty. (a) Inferior view. (b) Side view

Trocar Configuration

The trocar configuration for a left versus right pyeloplasty is basically a mirror image of itself (Figs. 29.4 and 29.5). One notable difference is the possibility of needing an extra trocar for liver retraction during a right pyeloplasty, although the renal pelvis can be accessed adequately in most cases without this extra trocar. We typically use the 5 mm trocars for robotic arm access when the patient is younger than 8–10 years, otherwise the 8 mm trocars are used.

Fig. 29.4

Trocar configuration for left robotic pyeloplasty. Yellow port is for the camera and the orange ports are for the working instruments. In smaller children, very large renal pelvis or a lower renal pelvis, the inferior working port should be moved inferior and medial as indicated by the yellow arrow

Fig. 29.5

Trocar configuration for right robotic pyeloplasty. Yellow port is for the camera and the orange ports are for the working instruments. In smaller children, very large renal pelvis or a lower renal pelvis, the inferior working port should be moved inferior and medial as indicated by the yellow arrow

Alternatively, the trocar configuration can be shifted caudally so that the camera port is a couple finger breadths above the pubic bone and the working ports placed at umbilicus and in ipsilateral lower quadrant. This would eliminate the scar in the midline of upper abdomen in place of a scar in low midline presumably under the underwear line (Fig. 29.6) [1].

Fig. 29.6

Trocar configuration for concealed ports (HIDES) technique. Yellow port is for the camera and the orange ports are for the working instruments

We have found that an assistant port is not needed in most cases. If an assistant port is needed, we typically place this lateral to the contralateral rectus muscle between the upper working port and camera port.

Instrumentation and Equipment List

Equipment

da Vinci^® Surgical System (3-arm system; Intuitive Surgical, Inc., Sunnyvale, CA)
EndoWrist^® Monopolar Hook, 5 or 8 mm (Intuitive Surgical, Inc., Sunnyvale, CA)
EndoWrist^® Maryland Dissector, 5 or 8 mm (Intuitive Surgical, Inc., Sunnyvale, CA)
EndoWrist^® DeBakey Forceps, 5 or 8 mm (Intuitive Surgical, Inc., Sunnyvale, CA)
EndoWrist^® Curved Monopolar Scissors, 8 mm (Intuitive Surgical, Inc., Sunnyvale, CA)
EndoWrist^® Round Tip Scissors, 5 or 8 mm (Intuitive Surgical, Inc., Sunnyvale, CA)
EndoWrist^® Needle Driver , 5 or 8 mm (Intuitive Surgical, Inc., Sunnyvale, CA)
InSite^® Vision System with 30° lens (Intuitive Surgical, Inc., Sunnyvale, CA)

Trocars

10 mm trocar
8 mm robotic trocars (2, if child is older than 6 years)
5 mm robotic trocar (option for smaller patients, although the 5 mm instruments are not as precise or dexterous as the 8 mm instrument) (usually 2; if you need liver retraction during a right pyeloplasty then you will need 3, or a 3.5 mm cannula)
Recommended sutures:
Preplaced fascial box stitch: 2-0 or 3-0 polyglactin suture
Hitch stitch: 2-0 or 3-0 PDS on SH needle
Pyeloplasty anastomosis : Monocryl or polyglactin suture, size depending upon age (we use: neonate to 6 months 6–0, 6 months to teen years 5–0; Length of suture approximately 12–14 cm).
Skin Closure: 4-0 or 5-0 monocryl suture

Recommended Ureteral Stent

Ages 0–6 years: 3.7 Fr double J and 0.028 in. wire; length: age plus 10 cm
Ages over 6: 4.8 Fr double J and 0.035 in. wire
Alternatively can use 4.8 Fr double J stent in all ureters that accommodate this size and only use smaller size stent in ureters that will not.

Instruments Used by the Surgical Assistant

Maryland grasper
Suction irrigator device
Cold scissors for cutting sutures

Step-by-Step Technique (Video 29.1)

Step 1: Ureteral Stent Placement

With the patient in lithotomy or frog-legged position, perform a retrograde pyelogram and place ureteral stent on the affected side up to the area of obstruction. Leave a string attached to the ureteral stent and tape string to inside of leg. This permits removal in clinic at a later date without cystoscopy.

Alternatively, ureteral stent placement can be done antegrade later in the operation (see below). This allows possible improved ease of dissection of renal pelvis and UPJ with pelvis still full and not drained by ureteral stent.

We do not perform a retrograde pyelogram for typical cases of UPJ obstruction with classic imaging findings in which an antegrade stent is planned. However, we have a low threshold to obtain a retrograde pyelogram and will always obtain one if history is unusual or if anatomy is atypical (fusion or malrotation, concern for ureteral polyp, etc.).

Step 2: Abdominal Access and Trocar Placement

For a left UPJO , reposition the patient in a left modified flank position as noted above; then, for trocar placement, rotate the table so the patient’s abdomen is 0°. The 10 mm camera trocar is placed in the area of the umbilicus, using the Hasson open technique with 2-0 polyglactin suture on a UR-6 needle or a 3-0 polyglactin suture on a CT-2 needle bent accordingly. These are pre-placed fascial box stitches (used later for closure). Working trocars are then placed sharply under direct vision after pre-placing the fascial box stitches. Rotate the patient to approximately 60° (30° from table rotation and 30° from the wedge placed earlier) and dock the robot.

Step 3: Access to Ureteropelvic Junction (Table 29.1)

Table 29.1

Access to ureteropelvic junction : surgeon and assistant instrumentation

Surgeon instrumentation		Assistant instrumentation
Right arm	Left arm	• Suction-irrigator
• Monopolar hook tip cautery (5 or 8 mm)	• Maryland dissector (5 mm cold; 8 mm bipolar)
• Monopolar scissors (8 mm)	• Maryland dissector (5 mm cold; 8 mm bipolar)
Endoscope lens: 30° down

Displace small bowel away from the surgical field and toward the midline. At this point, if the UPJO is obvious through the mesentery, then a transmesenteric approach may be followed to gain access to the ureteropelvic junction (UPJ) (Fig. 29.7). Otherwise, continue as below. Retract the colon medially and identify the white line of Toldt. Pick up the parietal peritoneum and make an incision extending from above the likely area of the renal pedicle to the aortic bifurcation using the hook electrocautery (5 mm or 8 mm) or hot scissors (8 mm) (Fig. 29.8). Expose the ureter distal to the UPJ being careful not to jeopardize the segmental blood supply in the area. Also, be aware of the gonadal vessels running parallel to the ureter in this area. Dissect proximally along the ureter. As the kidney is approached, look for lower pole vessels that are common with this anomaly (Fig. 29.9). Isolate and dissect around these vessels. Do not ligate them as this could lead to segmental renal ischemia. Before excessive mobilization, determine whether the vessels appear to be contributing to the obstruction if possible. This will determine whether ureteral transposition anterior (usually) to the vessels is needed.