Fig. 11.1
Right epigastric vessels bleeding after a trocar insertion
Bipolar coagulation and clipping are often effective in controlling any bleeding. If the bleeding is persistent, suturing through the abdominal wall with the aid of a straight needle, encaging the bleeding vessel, is very useful. The suture should be released 2 days after the initial operative procedure [11]. Remember to inspect all trocar sites after removal because bleeding may not be apparent until trocar removal and lowering the pneumoperitoneal pressure [11].
Careful inspection of the abdominal wall via the laparoscope before trocar insertion is useful. It is also useful to prepuncture and visualize the site of planned trocar insertion [11]. The first robotic instrument has to be inserted under direct vision because it has no memory and can go further than desired. Inserting the instrument under direct vision is also required because touching the clutch of the robotic arm causes it to lose its memory.
During the course of a laparoscopic procedure, bleeding at any trocar site should not be overlooked. Bleeding might be a harbinger of vascular injury. In this situation, open suture ligation via the “cut-down” technique, or fascial closure with the Carter–Thomason device, can be used to achieve vascular control [12].
Large abdominal or scrotal hematomas have been described due to small amounts of bleeding that were not seen during surgery. Care must be taken with the position and movement of the robotic arms during surgery, especially when one of the arms is placed outside the field of view, because the pressure of the instrument on vascular structures could cause delayed injuries due to intramural hematomas or thrombosis due to blood stasis [13].
Subcutaneous Emphysema
Although insufflation with carbon dioxide (CO2) for laparoscopic procedures is considered to be relatively safe, there exists a small but important risk of developing complications, including massive subcutaneous emphysema (SE), hypercarbia, pneumothorax, pneuomomediastinum, and even CO2 embolism [14].
The incidence of SE varies from isolated and confined in a small space to extravasation outside of the abdominal cavity extending into the labia, scrotum, legs, chest, head, and neck. The literature range is 0.43–2.3% for grossly detectable SE. It has been shown in postoperative computed tomography scans (Fig. 11.2) from laparoscopic cholecystectomy patients that there was a 56% rate of grossly undetectable or clinical subcutaneous emphysema 24 h after the procedure [15].
Fig. 11.2
Large SE over the right costal margin seen on a CT scan
SE, in its mild form, is not uncommon after laparoscopic MIS. It generally resolves within 1–2 days, but its true incidence is underreported [16, 17].
The clinical significance of SE is development of hypercarbia and acidosis. The increased risk of hypercarbia is caused by the large peritoneal surface tissue area exposed to CO2 [18, 19]. A combination of factors contribute to increased arterial partial pressure of CO2 in arterial blood: rapid absorption of CO2, reduced diaphragmatic movement, a decrease in residual functional capacity, and decreased pulmonary CO2 excretion, leading to ventilation-perfusion mismatch [20, 21]. Cardiovascular compromise can be caused by mechanical factors from increased intraabdominal pressure, affecting ventilation and venous return and with accumulation of CO2 in the circulation, leading to acidosis and cardiopulmonary system compromise [22]. Hypercarbia increases heart rate, systemic blood pressure, central venous pressure, cardiac output, and stroke volume, and it decreases peripheral vascular resistance because of the release of epinephrine and norepinephrine [23–28].
The CO2 may also track along the pre-fascial planes and cause life-threatening conditions such as pneumothorax, pneumomediastium, pneumopericardium, and the most devastating complication: gas embolism [14].
Factors associated with SE during MIS pneumoperitoneum are methods of laparoscopy MIS (video assisted or robotic) [29], insufflator settings for pressure and flow, actual IAP, actual flow rate, number of abdominal entry sites, size and geometry of fascial incision to trocar size of entry site, snugness of fit between trocar and fascia, number of times the entry site is entered, amount of torquing and pressure on entry sites, vectoring of the laparoscope, fulcrum effect between laparoscope and fascia, length of procedure, volume of gas used, patient age, patient BMI, coexisting metabolic diseases, tissue integrity, type of trocar used, and purposeful extraperitoneal dissection. The total amount of gas used may or may not be related to the length of time of the procedure and may be more important than the length of time of the procedure. Insufflator settings for pressure and flow rate influence insufflation dynamics, the amount of gas absorption or extraperitoneal extravasation with higher pressures, and flow rates contributing to the increased incidence of gas extravasation.
Peritoneal separation can occur because of multiple repetitive movements of the laparoscope acting through a cannula. The cannula acts as a fulcrum for the laparoscope (lever arm) to act as a class-one lever and force multiplier. The pivot point is the fascial entry site. The resulting mechanical advantage can extend the original peritoneal penetration site, allowing gas extravasation into planes outside of the abdomen. During robotic surgery, instrument manipulation occurs without the surgeon’s ability to sense or appreciate these forces because of lack of haptic feedback and the inability to see the relationship of the length of the laparoscope to the abdominal entry point. Separation of the surgeon at a console from the patient removes the ability to see the results of their hand movements and how this affects trocar angle and amount of stress and torquing of the peritoneal entry site, because there is little to no haptic feedback (tactile) to alert the surgeon of overstressing the port entry sites. Attention of the assistant at the operating table is important for monitoring not only the robotic instruments but also the entry sites and robotic movements that may compromise the port sites.
Torque is the force causing an object to rotate about an axis, fulcrum, or pivot. The laparoscope rotates about an axis or pivot point as it passes through the cannula, penetrating the abdominal wall. The distance from the pivot point to the point where the force acts is the moment arm, creating a vector that can increase the size of the peritoneal entry defect. Torque pressure sensation can be appreciated during traditional straight laparoscopic procedures but is not felt during robotic procedures, because there is a loss of force feedback and haptic awareness. During robotic procedures, force feedback related to angulation of instruments and trocars and lack of direct visualization of the cannula by the operating surgeon increases the potential for overstressing tissues and loss of tissue layer integrity, which leads to gas extravasation tissue dissection and SE [30].
To reduce the likelihood of subcutaneous emphysema, the following are recommended: awareness of its potential; physician vigilance; attention to detail regarding abdominal entry; monitoring insufflator settings for pressure, flow rate, and volume of gas with alarm settings; quickness, but not rushing, to complete the procedure (length of procedure and gas consumption relate to the condition); reduce the number of attempts to enter the abdomen; have a snug trocar skin condition; test for correct placement by initial IAP assessment; and monitor end tidal CO2 [30].
Postoperative Complications
Pain
There are several types of pain associated with robotic surgery: incisional port site pain, pain from the peritoneum being distended with carbon dioxide, visceral pain, and shoulder tip pain. The most severe pain occurs immediately after operation and decreases with time [31, 32]. If the pain is not treated effectively, readmission for pain makes the previous benefit of laparoscopic surgery for a shorter hospital stay redundant.
The initial concept of preemptive analgesia was formulated by Crile [33] in 1913 when he described the use of regional techniques to prevent postoperative pain; it is thought to prevent central sensitization and hyper-excitability, which decreases postoperative pain by preventing wind-up and is thought to decrease the incidence of chronic pain [34]. Pre-emptive analgesia is defined as any treatment that prevents establishment of central sensitization caused by incisional and inflammatory injuries and should start before incision, covering the surgical period and the initial postoperative period [34–36]. There remains controversy over the effectiveness and timing of preemptive analgesia, there is only one study that looks at preemptive analgesia in a urological laparoscopic procedures and one systematic review and meta-analysis from nonurological studies that looks at the impact of local analgesia timing and postoperative pain. Coughlin et al. [37] analyzed 26 studies and showed that surgeons should use local analgesia in laparoscopic surgery to decrease postoperative pain (infiltration at port sites or intraperitoneally), but the timing of administration is significant only for intraperitoneal infiltration but not for port infiltration with local anesthetic. Pre-incisional use of bupivacaine has been recommended (Grade A evidence) in another systematic review of interventions in laparoscopic cholecystectomy [38].
Surgical Site Infection (SSI)
SSIs are infections consequent to the surgery, which are present within a month of the operative procedure. According to the definitions developed by the United States Centre for Disease Control (CDC), SSIs were categorized into [39]: (1) superficial SSIs which involve skin and subcutaneous tissue; (2) deep SSIs, which involve fascia and muscle layers; and (3) organ/space SSIs. Wounds are classified as (as per CDC criteria for SSI 2015) [39]: (1) clean: A surgical wound that is neither exposed to any inflamed tissue nor has breached the gastrointestinal, respiratory, genital, or uninfected urinary tract; (2) clean-contaminated: Surgical wounds where there is controlled entry into the gastrointestinal, respiratory, genital, or uninfected urinary tract with minimal contamination; (3) contaminated: Fresh wounds related to trauma, surgical wounds with major breach in sterile technique or gross contamination from the gastrointestinal tract, and incisions through nonpurulent inflammatory tissues; and (4) dirty or infected: Old wounds following trauma having devitalized tissue and surgical procedure performed in the presence of active infection or visceral perforation.
Most of the surgical procedures done by MIS belong to classes 1 and 2 wounds. The human body hosts a variety of microbes that can cause infections. When the host systemic immunity is suppressed due to any disease, medications, or disruptions of the integrity of the skin or mucous membranes secondary to surgical insult, patients’ own commensal microbial flora may cause infection. The SSI in MIS manifest in the form of seropurulent discharge from the port sites with surrounding skin inflammation or symptoms related to the organ/space infection (Fig. 11.3).
Fig. 11.3
Purulent discharge from umbilical incision
Several authors have found that SSI rate is much higher in conventional surgical procedures than in MIS [40–42]. Besides the smaller incisions, the immune functions are less affected in LS as compared with open surgery [43].
SSI soon erodes the advantages of MIS, with the patient becoming worried with the indolent and nagging infection and losing confidence on the operating surgeon. There occurs a significant increase in the morbidity, hospital stay, and financial loss to the patient. The whole purpose of MIS to achieve utmost cosmesis is turned into an unsightly wound, and the quality of life of patients is seriously affected [44].
The active surveillance for SSIs in MIS remains a challenge, due to the early discharge and day care setting [40, 42]. In the absence of postdischarge surveillance, it is estimated that a third of all SSIs will be missed [45].
A number of contributing factors are somewhat responsible for the emergence of postoperative PSIs. Antibiotics always may not be the answer to this problem. Thus, using them irrationally, as is often done will only result in the emergence of multidrug resistant microbes. The majority of the reports of postoperative wound infection are of superficial SSIs [42]. The risk factors for SSIs are preoperative stay longer than 2 days [40], duration of operation longer than 2 h [40], emergency/multiprocedure surgery and surgery in acutely inflamed organs [46, 47], history of nicotine or steroid usage, diabetes, malnutrition, long preoperative hospital stay, preoperative colonization of nares with Staphylococcus aureus, or perioperative blood transfusion [48, 49]. Obesity, prophylactic antibiotics, and drains have no effect on the rate of SSIs following laparoscopic cholecystectomy [50]. SSIs are also more common in the umbilical port [42]; the infection rate may depend upon the port through which the specimen is extracted. The infected specimen should be removed in an endobag to prevent wound infection and accidental spillage of contents or occult malignant cells.
Specifically about after radical prostatectomy, there was reported a higher incidence of SSI when comparing patients submitted to open radical prostatectomy (ORP) and robotic-assisted radical prostatectomy (24.5% vs 0.6%). Furthermore, SSIs in patients undergoing RARP resolved more quickly (median, 7 vs 16 days) and were less likely to require wound incision and/or drainage (1 vs 84 patients), hospital readmission (0 vs 11 patients), or return to the operating room for debridement (0 vs 6 patients) [51].
SSIs are of two broad varieties based on the timing when they are present. The more common type manifests early, within a week of the surgical procedure. Gram-positive or Gram-negative bacteria are the usual offending organisms which are contracted from the native skin or infected surgical site. They usually respond well to the commonly used antimicrobial agents. The other variety is caused by rapid growing atypical mycobacterium species, which has an incubation period of 3–4 weeks. They show a poor response to the usual antimicrobial agents [52].
Wound discharge and erythema around the port site are the most common presentation of nonmycobacterial infection usually occurring within a week of the surgery. They are usually limited to the skin and subcutaneous tissue [42, 53]. There may be surrounding tissue inflammation with pain or tenderness and low-grade fever [54]. Gram stains and culture sensitivity of the pus from port site wounds are to be taken. The swabs obtained are processed aerobically and anaerobically by standard methods to find the nonmycobacterial isolates. Staphylococcus aureus strains are usually isolated from clean wounds. Daily dressing, cleaning of the wound, and a course of empirical antibiotic are started. Specific antibiotics as per the culture and sensitivity report are to be given subsequently. Drainage and debridement may sometimes be required for assisting in wound healing.
The delayed type of presentation commonly caused by mycobacteria manifests nearly a month after surgery, in the form of persistent multiple discharging sinuses or lumps/nodules, not responding to antibiotics. There may be pigmentation and induration at the port site starting in a single port and spreading to others [44].
Trocar Site Herniation
Since the introduction of MIS , trocar port site herniation has become a well-recognized complication. Available estimates of the incidence of laparoscopic trocar site herniation across all surgical subspecialties, based on the largest available studies, range from 0.2% to 1.3% [55–59].
Three types of trocar site herniations have been described: (1) fascial and peritoneal separation (associated with early presentation), (2) fascial separation with intact peritoneum (associated with a later presentation), and (3) herniation of the entire abdominal wall (seen at the time of trocar removal or shortly after surgery) [60]. Early-onset hernias are the most commonly described and typically become apparent within 2–12 days after surgery. Patients with early-onset hernias most often present with small bowel obstruction (Fig. 11.4), which can be a surgical emergency, often necessitating reoperation [57]. It has been reported that approximately 16% of trocar site herniations must be emergently repaired [55].
Fig. 11.4
Small bowel obstruction after early-onset trocar site hernia
Patients with late-onset hernias generally present with a bulge several months after surgery, ranging from 0.7 to 27 months [57]. The rate of reoperation in these patients is low, as late-onset hernias can often be managed conservatively, as incisional hernias.
Incisional hernia represents a potentially serious complication to minimally invasive surgery because most require further surgical intervention [57]. In general, incisional hernias represent a technical issue.
Multiple risk factors for trocar site herniation have previously been identified. The most commonly cited risk factor is trocar size, with trocars larger than 12 mm being associated with significantly increased risk [56, 58], but there is a report of a single-case report of herniation at an 8-mm trocar site following robotic prostate surgery [60] and another previously published study on trocar site herniation after robotic surgery is a report in the urologic literature, in which two herniations were seen at 10-mm and larger trocar sites and no herniations were seen at robotic trocar sites [61].
Other previously identified risk factors for trocar site herniation include pyramidal trocars, a long duration of surgery, manipulation of the trocar for specimen retrieval, larger prostate weight, history of prior laparoscopic cholecystectomy, closure of the fascia at the time of surgery, umbilical location (Fig. 11.5), older age, and a higher body mass index [56, 58, 62].
Fig. 11.5
CT scan of an incisional periumbilical hernia (white arrow)
Special attention has been taken to the extraction site of the specimen during RARP. Studies have shown that the extraction site at midline of the abdomen in longitudinal incisions have a higher chance of becoming hernias and suggestions of preferential extraction sites to minimize incisional hernia rates should be incisions off the midline [63, 64]. Most of the extractions site used for robotic urology is the camera port located usually at the midline of the abdomen.
In one single-surgeon MIRP series, incisional hernias occurred more often after a vertical than after a transverse incision [65], corroborating a Cochrane review of seven trials of abdominal surgery, in which a significant difference was seen in favor of the transverse incision over the midline [66].
A large Danish review of more than 7,000 laparoscopic procedures showed that emergent reoperation was needed in 16% (15/95) of patients with trocar site herniation [55]. No patients in this large study or our study required bowel resection. The need for bowel resection due to incarcerated hernia has been reported [60, 67]. A review of 30 case reports of trocar site herniation reported a 17% (5/30) incidence of need for bowel resection when emergent reoperation was performed [57].
Inguinal Hernia
Inguinal hernia (IH) after ORP using the retropubic approach is well described [68]. Recent reports suggest that the frequency of inguinal hernia within 4 years after surgery is 12–21% after ORP [69, 70] and 6% after MIRP [71].
It has been reported a lower incidence of postoperative IH after robotic-assisted radical prostatectomy (RAPL) than ORP. The two procedures differ concerning the incision through the abdominal wall [71]. When ORP is performed through a 10–15 cm long incision in the midline between the symphysis pubis and the umbilicus, the RALP is performed through five or six shorter incisions spread out on the lower part of the abdomen, suggesting that the length of the incision is of great importance for the development of IH. They reported a postoperative IH incidence as high as 38.7% after RRP, but only 2.9% in a group of 272 patients in whom the procedure was performed through a so called “mini-laparotomy” incision of only 6 cm [72].
It has been also reported an IH incidence of 1.8% after radical perineal prostatectomy, in which the whole procedure is performed through a perineal incision, and consequently, there is no abdominal incision at all [73].
Reinforcing the idea that the length, and possibly the placing, of the abdominal incision seems to affect the development of postoperative IH, it was published a study with 5478 men treated by RRP for the outcome of IH repair rates, with an incidence of IH of 17.1% at 10-years follow-up [74]. The corresponding rate after transurethral resection of the prostate was 9.2%.
Although it is not known who is destined to develop IH after RARP, the risk factors of increased age, lower BMI, and previous inguinal hernia repair for post-RP inguinal hernia might define a subset of patients that should undergo careful preoperative and intraoperative evaluation for subclinical inguinal hernia so that concurrent inguinal hernia repair can be undertaken at RARP [75]. Defining the role of prophylactic inguinal hernia repair in those without a subclinical inguinal hernia would require evaluation.
Our experience and observation is that after the dissection is performed for the robotic prostatectomy and the internal ring of the inguinal canal is altered and the fatty tissue removed there is a change of the patients that had a nonclinical inguinal hernia become symptomatic after the surgery.
Port-Site Metastasis
Postlaparoscopic occurrence of port-site metastasis (Fig. 11.6) refers to tumor foci either localized at single or multiple locations under the skin or in the scar tissue of the abdominal wall adjacent to the port [76]. Port-site metastasis is a rare complication that may occur following laparoscopic surgery for malignant tumors of the urinary system, with an incidence of 0.09–0.73% of all patients who undergo laparoscopic surgery for urological malignancies [77, 78]. Previous studies have reported ~50 cases of abdominal wall implantation metastasis following surgical resection of malignant tumors of the urinary system [79], of which, 9 cases occurred following surgical resection of renal carcinoma [80–93]. Thus, this indicates that the occurrence of port-site metastasis subsequent to laparoscopic radical resection of renal carcinoma and nephron-sparing surgery is relatively rare.
