The first step to preventing complications in pediatric robotic surgery is proper patient positioning with adequate padding. Although positioning varies between surgeons and procedures, several universal measures for the prevention of nerve injury are noted below. In the supine position, maintaining upper extremity abduction to less than 90° reduces the risk of brachial plexus injury. Furthermore, ensuring a supinated or neutral position of the forearm prevents ulnar nerve compression [4]. The use of Trendelenburg position should be avoided for prolonged periods as this can place the pediatric patient at risk for both positional migration and cardiopulmonary changes. After a patient is secured to the operating room table, communication with the anesthesiologist is vital to ensure that respiratory excursion is not compromised. Rehearsal positioning of the bed prior to docking of the robot can confirm proper secure positioning since the patient position should not migrate once the robotic is docked. With lithotomy positioning, care must be taken to limit pressure of the fibular head on the peroneal nerve. And during flank positioning, an axillary roll placed between the chest walls caudal to the dependent axilla and the bed prevents compression of the brachial plexus.

Although limited data exists regarding peripheral nerve injury during robotic procedures in the pediatric population, the adult experience has shown that upper extremity ulnar and brachial plexus injuries are the most common [4]. Review of a multicenter database of 880 pediatric robotic urologic surgeries identified one patient with knee numbness and another with facial swelling that resulted from positioning [5]. These complications were self-limited and resolved spontaneously similar to the majority of positioning-related injuries. However, if prolonged sensory or motor deficits are persistent, referral to pediatric neurologic specialists for further evaluation may be indicated.

There are two classic techniques for intra-abdominal access: Veress (closed) and Hasson (open). The closed technique consists of a Veress needle (blunt-tipped, spring-loaded, inner stylet surrounded by a sharp needle) that is inserted into the abdominal cavity without visualization. The blunt tip extends forward to protect the abdominal viscera and vasculature from the sharp needle after lower resistance is encountered upon entry into the peritoneal cavity. The needle is often passed at a 45 ° angle in nonobese patients and adjusted to 90 ° in obese patients to avoid visceral and vascular injuries. Once the needle is placed, aspiration and/or injection of fluid prior to insufflation is recommended to confirm proper placement [6, 7].

The open Hasson technique can be used in all patients and is especially preferable for patients with obesity, prior abdominal surgery (with possible intra-abdominal adhesions), or failed Veress needle access. After the initial skin incision, a pair of stay sutures at the fascia level can assist with the fascial opening and allow for peritoneal entry under direct vision and therefore without the need for confirmation of intraperitoneal placement as with the closed technique [6]. Once the trocar is placed, the stay sutures can be used to secure the port in place.

Regarding the prevention of access complications, the open technique is often utilized since the anteroposterior diameter of the pediatric abdomen is relatively narrow. Other recommendations include decompression of the stomach with a nasogastric tube and of the bladder with Foley drainage to avoid injury to a distended intra-abdominal organ . Subsequent port placement should always be performed under direct visualization and with blunt-tipped trocars and especially for accessory ports that may be placed outside of the visual field (behind the camera). In patients with previous abdominal surgeries, ventriculoperitoneal shunts, and/or previous bladder reconstruction surgery, access superior to the umbilicus may facilitate safe entry.

Intra-abdominal access injuries are often recognized immediately and can involve vasculature, intestine, or nerves, with an incidence as high as 5.4% with the Veress technique [7]. Passerotti et al. and others noted that the best predictor for avoiding complications was the surgeon’s previous experience with laparoscopic procedures [8–10]. The treatment of access complications will be addressed below.

Vessel injury is the most common type of intraoperative complication with minimally invasive surgery . A large multi-institutional analysis showed a complication rate for vascular injury of 0.4% in 880 pediatric robotic urologic procedures [5]. Vascular injuries can occur during intra-abdominal access, port placement, instrument insertion, cauterization of surrounding structures, excessive traction, and careless handling of needles. Common preventive measures include the introduction of ports and instruments with care under direct visualization, dissection with caution to surrounding tissues and vessels, and the avoidance of excessive traction. A set of vascular open instruments should always be available in case rapid conversion to an open procedure is needed. Any vessel injury should be identified and addressed immediately to avoid major blood loss and deterioration of hemodynamic status. If the bleeding source is venous, direct pressure or cauterization can often help to control this bleeding [9, 10]. If a major vessel is injured, the trocar should be left in place and rapid conversion to open exploration is warranted. For minor vessels, if the bleeding cannot be controlled laparoscopically, conversion to open surgery is also recommended [5, 11, 12]. If vascular entry of CO2 during insufflation is suspected, the patient should be placed in the left lateral decubitus position to trap the embolus in the right atrium. Treatment of this potentially catastrophic complication can often be accomplished with central line aspiration and transesophageal ultrasonography [6].

Intestinal injury can occur during intra-abdominal access, port placement, and instrument insertion, as well as with electrocautery. The extent of these injuries can vary from simple serosal tears to full-thickness enterotomies. Often, the careful handling of instruments and needles in the abdominal cavity can help to prevent these injuries. In addition, the appropriate placement of insulation tip covers can prevent unintentional cauterization of adjacent tissues. However, for patients with a history of previous abdominal surgeries and/or ventriculoperitoneal shunt placements, a higher risk of bowel injury may be present due to the presence of intra-abdominal adhesions.

For serosal tears, the repair should include imbricating seromuscular sutures. If a full-thickness enterotomy is seen, repair with one or two layers of braided absorbable suture is needed. If multiple tears are present in a bowel segment, bowel resection and primary anastomosis, or intestinal diversion, may be required. If a bowel injury is not immediately identified at the time of surgery, patients can present a few days later with signs and symptoms of peritonitis (i.e., abdominal pain, ileus, leukocytosis, fever with tachycardia, and hypotension) that can progress to sepsis and shock in some cases. Early identification of these injuries in the postoperative period is critical and usually leads to immediate surgical intervention. Laparotomy with intestinal repair or diversion as well as evacuation of debris, secretions, and pus is necessary along with copious irrigation of the peritoneal cavity with antibiotics and saline. An intra-abdominal drain is left in place to prevent re-accumulation of a closed fluid collection [5, 6, 12]. Consultation with the general surgery service is usually recommended for these cases.

Lost needles during a robotic procedure should be avoided at all costs as they can lead to potential injury as well as additional operative time during the search for the lost needle. Maintaining strict and accurate needle counts during surgery is essential to prevent misplacement of a needle. In addition, the use of a single needle at a time and the verbal reporting by the bedside assistant of the introduction and removal of needles are critical for maintaining accurate counts. If a needle is lost during surgery, it is recommended to avoid movement of the instruments or intestines since movement can alter the original position of the needle and lead to increased difficulty of the search. Undocking of the camera as well as an intraoperative X-ray can assist with locating the needle if initial visual inspection is not successful. Once a lost needle is found, assessment of the bowel and surrounding structures should be performed to evaluate for injury and assess whether repair is warranted [12].