Robotic Inguinal Hernia Repair for Incarcerated Hernias

Introduction

Since inguinal hernias comprise ∼75% of abdominal wall hernias, it is imperative to explore options for their surgical management to improve patient outcomes. The safety and feasibility of robotic inguinal hernia repair (rIHR) have been shown in several studies.^1,2 When faced with emergent situations, however, the most common approach to incarcerated IHR is open surgery. However, as minimally invasive surgery advanced, scientific literature also expanded to demonstrate promising outcomes after emergent laparoscopic IHR.^3,4

Robotic technology is a relatively recent addition to the field of hernia surgery, necessitating further investigation into its utility in various settings. Barriers to adopting robotic technology, particularly in the emergency setting, include longer operative times, a lack of adequate robotic coverage and staff training, and a steep learning curve for surgeons.

In this study, we aim to provide the first investigation of postoperative outcomes after robotic emergency inguinal hernia repair (rEIHR). Based on the amassed experience of both the surgeon and staff, including a variety of emergent robotic procedures, we hypothesize that rEIHR is a feasible option for these hernias.

Materials and Methods

The data for this study were obtained from a prospectively collected database of cases performed between February 2013 and May 2020. From this case series, patients who presented with incarcerated inguinal hernias to the emergency department, and who underwent subsequent robotic inguinal hernia repair within 24 hours of presentation, were included in this study. Elective hernia repairs and concomitant nonabdominal wall procedures were excluded. Unless contraindicated due to septic shock or severe cardiopulmonary disease, the surgeon's preferred approach for these hernias is rIHR. The variables included patient characteristics (age, gender, body mass index, comorbidities, American Society Anesthesiology score, and Acute Physiology and Chronic Health Evaluation II score), hernia characteristics (etiology, side, and hernia contents), operative variables (the type of mesh, mesh dimensions, console and skin-to-skin times, estimated blood loss in milliliters, intraoperative complications, and conversion to open or laparoscopic approach), and postoperative variables (postoperative pain scores, the hospital length of stay [LOS], emergency readmission within 30 days after discharge, and complications).

Hernias were classified according to the European Hernia Society classification. ⁵ Postoperative pain scores were documented by an anesthesiologist using a 0–10 numeric rating scale system (0, no pain; 10, the worst pain). The pain score was recorded just before the patient left the postanesthesia care unit (PACU). The total amount of narcotic-analgesic received while in the PACU was also calculated. The LOS, in days, was defined as the difference in time between the date of the operation and the date of hospital discharge.

Postoperative complications were reviewed as documented in the surgeon's follow-up visit notes, as well as the medical records and clinical charts of the patients. All complications were categorized according to the Clavien–Dindo classification system. ⁶ The Comprehensive Complication Index (CCI^®, University of Zurich, Zurich, Switzerland) was used to assess the morbidity. ⁷

Surgical technique

The patient was placed in the supine position, and a Foley catheter was inserted (Fig. 1). After appropriate preparation, a Veress needle was inserted into the left upper quadrant to insufflate the abdomen, and a total of three 8.5 mm trocars were inserted 8 cm apart and 4 cm above the level of the umbilicus and off-midline. The patient-side cart of the da Vinci surgical robotic system (Intuitive Surgical, Sunnyvale, CA) was docked. Each procedure involves an average of three instruments, including a 0° scope. After docking, the inguinal hernia is identified, and peritoneal dissection is initiated 8–10 cm above the internal inguinal ring, starting at the median umbilical fold and proceeding laterally toward the anterior superior iliac spine. The dissection was extended inferiorly toward the deep inguinal ring and medially at least 2 cm between Cooper's ligament and the bladder to allow adequate mesh overlap in the space of Retzius. Inferior epigastric vessels were preserved, and cord structures were separated, and the hernia contents were then reduced. Indocyanine green was used to assess bowel viability if needed. In the case of a direct hernia, the plication of the transversalis fascia was performed in cases with a large defect, to obliterate the direct space. For indirect hernias, the hernia sac was carefully dissected from its attachments to avoid injury to structures in the triangle of doom. If present, lipomas were either reduced or excised. The recommendations of the International Hernia Collaboration's critical view of the myopectineal orifice (MPO) were followed. ⁸ After the evaluation of the MPO for any hidden hernias and visualization of all anatomical elements, a minimum mesh size of 15 × 10 cm was introduced to cover the MPO. The peritoneal flap was then closed using absorbable barbed suture. Any fascial incisions >10 mm, if present, as well as skin incisions, were closed using absorbable sutures after administration of local anesthetic (1% bupivacaine hydrochloride) at the trocar sites.

OPEN IN VIEWER

FIG. 1.

(a) Reduction of an incarcerated right direct hernia (Richter's hernia); (b) preperitoneal dissection and exposure of the hernia defect; (c) mesh placement covering the entirety of the MPO; (d) peritoneal flap closure using absorbable suture. MPO, myopectineal orifice.

Results

From 616 patients who underwent rIHR in the aforementioned timeframe, a total of 19 patients were included. Patient characteristics are presented in Table 1.

Twenty-three rEIHRs were performed in 19 patients. In 2/19 patients, robotic transversus abdominis release (TAR) for incisional hernias was performed simultaneously with rEIHR. The majority of the hernias were indirect (lateral) hernias and located on the right side. One patient (5.3%) required a repair due to the recurrence of a hernia, which had been previously performed using an anterior approach. All hernias were incarcerated; however, hernia reduction was not needed in one patient due to spontaneous reduction during pneumoperitoneum. The enlargement of the hernia defect was not required in any of the patients. Although intracorporeal gentle traction was used in 10 patients, a combination of external manual pressure and gentle traction was used in 7 patients. In one patient, reduction en masse of the hernia sac and its contents was needed. The details of the hernia characteristics are presented in Table 2.

In 3 (15.8%) patients with a direct hernia, the imbrication of the hernia sac was performed. ProGrip™ (Medtronic, Minneapolis, MN) mesh was used in 18/23 hernia repairs, whereas 3DMax™ Mesh (Bard Davol, Inc., Warwick, RI) was used in 5/23 hernia repairs. None of the repairs involved suture or tacker fixation. There were no intraoperative complications, and no drains were placed. None of the procedures were converted to open or conventional laparoscopy. Operative variables are listed in Table 3.

The median (IQR) pain score was 3 (0.5–5). During the PACU recovery period, 26.3% of patients did not require any pain medication. The median (IQR) morphine milligram equivalent (MME) was 10 (2.5–15). The mean hospital LOS was 1.4 days (min–max: 0–8). One (5.3%) patient was readmitted to the hospital within 30 days postoperatively due to ileus, which was managed conservatively. This patient initially presented with an incarcerated scrotal hernia and small bowel obstruction, which could cause prolonged ileus due to edematous and congested bowel.

No hernia recurrence was seen in the mean postoperative follow-up period of 31.7 (min–max = 0.6–66.1) months. One patient experienced SBO (Clavien–Dindo grade-2). One patient required an ICU follow-up immediately after surgery due to hypercarbia (Clavien–Dindo grade-4A) and also experienced postoperative urinary retention (Clavien–Dindo grade-I). The median CCI score was 0 (max = 43.3). There were no surgical site complications.

Discussion

Although elective repair of groin hernias through a minimally invasive surgical approach has been well documented in the literature, it is still controversial when it comes to incarcerated or strangulated groin hernias. For these hernias, in general, open approaches are preferred by many surgeons, likely due to concerns over possible iatrogenic injuries, which may occur while reducing the hernia sac contents. ¹⁰ In laparoscopic IHR, many different hernia reduction techniques have been described to reduce the conversion rate to an open approach. In a study comparing surgical outcomes between open and laparoscopic procedures for incarcerated/strangulated inguinal hernias by Chihara et al., ¹¹ it was concluded that laparoscopic reduction and herniorrhaphy is effective, safe, and feasible. In their series, 46/52 laparoscopic repairs were performed through a laparoscopic TAPP approach, using following reduction techniques: manual extracorporeal pressure in 10 (21.7%) patients, gentle intracorporeal traction in 9 (19.6%) patients, a combination of these two in 10 (21.7%) patients, and water pressure in 6 (13%) patients. Spontaneous reduction was noted in 10 (21.7%) patients, whereas conversion to an open approach was required in one patient. No enlargement of the hernia orifice was required in any of the patients who underwent laparoscopic TAPP repair, versus in one patient who underwent laparoscopic TEP. Taking into account the lack of haptic feedback in the robotic system, the surgical step involving hernia reduction is critical in avoiding iatrogenic injuries. In our study, we used manual pressure and/or gentle traction techniques in 17 patients and a “reduction en masse” technique in one patient, which is defined as the reduction of the hernia sac together with its intestinal contents so that the bowel still remains incarcerated.

In a study investigating whether prosthetic repair of incarcerated inguinal hernias is a reliable method, Derici et al. ¹² reported that the use of mesh is preferred because a significantly lower recurrence rate was observed after Lichtenstein repair compared with suture repair. The mean operative time for Lichtenstein repair was 70.4 minutes, whereas the mean operative time for primary repair was 70 minutes. In Chihara et al.'s study, ¹¹ the operative time of the laparoscopic group was significantly longer than that of the open group (126.4 minutes vs. 104.6 minutes). The necessity of bowel resection in both groups (29.6% in the open group vs. 13.5% in the laparoscopic group) may have resulted in prolonged operative times. Rebuffat et al. ⁴ analyzed the results of emergent laparoscopic repair of strangulated hernias and reported that the mean operating time was longer in cases requiring bowel resection (103 minutes vs. 55 minutes). In a recent study conducted by Mancini et al., ¹³ the median operative time was 81.3 minutes for 20 patients who underwent laparoscopic TAPP repair for incarcerated inguinal hernias over a 14-year period, ranging from 55 minutes to 137 minutes. Median operative time of 49 minutes was found for unilateral repairs, whereas a median time of 88 minutes was found for bilateral repairs. In this study, the mean console time was 62.8 (median = 39) minutes, and the mean skin-to-skin time was 75.9 (median = 52) minutes. Although there were no bowel resections, concomitant TAR repair for a recurrent incisional hernia was performed in 2 patients. When these 2 patients were excluded, the mean console time was 42.9 (median = 33) minutes, and skin-to-skin time was 55.6 (median = 45) minutes, which was similar to that of Rebuffat et al.'s study ⁴ group without bowel resections. Furthermore, the mean skin-to-skin time of unilateral and bilateral hernia repairs in our study was 47.7 minutes (median = 39.5 minutes) and 92.6 minutes (median = 107 minutes), respectively.

Regarding postoperative pain, Mancini et al. ¹³ reported that the evaluation of acute pain at 48 hours. after surgery, by a visual analog scale score, showed that the median value was 3, ranging from 1 to 5. They also noted that the most common postoperative symptom was shoulder pain, which easily resolved with a median of 1 ketorolac vial (30 mg/mL). Moreover, none of the patients in their series complained of pain 30 days after their surgery. In this study, the median pain score was 3 (IQR = 0.5–5), and the median MME dose was found as 10. None of our patients experienced chronic pain.

In terms of the hospital LOS, minimally invasive approaches to inguinal hernias show advantages over open approaches in the elective setting. ¹⁴ Similarly, a shorter hospital LOS was reported in favor of laparoscopic repair compared with open repair in the emergent setting. ¹¹ In a systematic review, including seven studies, with a total of 328 patients who underwent laparoscopically (TAPP/TEP) repair of incarcerated/strangulated hernias, an average hospital LOS of 3.8 (SD ±1.2) days was reported, keeping in mind that bowel resection or conversion were observed in some cases. ¹⁰ Fortunately, no patients required bowel resection in our series, and the mean hospital LOS was 1.4 days, ranging from 0 to 8 days.

Up to a 20% surgical site infection (SSI) rate has been reported in published outcomes of open mesh repair for incarcerated/strangulated inguinal hernias, none of which are mesh infections. ¹⁵ SSI rate increase as the rate of nonviable bowel resection increases. In a study with 73 patients who underwent laparoscopic TAPP for incarcerated inguinal hernias, only 1 (1.4%) patient experienced an SSI. ¹⁶ We did not observe any SSIs among our patients. This may be attributed to the fact that there was no breach in the sterility of the procedures. According to a systematic review/metanalysis by Aiolfi et al., ¹⁷ the estimated pooled prevalence of seromas/hematomas across 13 studies (1645 patients) was 4.1%. However, only 1.9% of patients were operated on for incarcerated hernias. No SSOs were observed in this study despite six inguinoscrotal repairs and an increased necessity for extensive dissection with incarcerated hernias, which has been associated with seroma formation. ¹⁸ This may be attributed to the precise dissection afforded by the robot and to the thorough and careful dissection of the hernia sac, along with sparing use of electrocautery.

There are a few limitations to the study. First, the retrospective nature of the study introduces some selective bias. Notably, these procedures were performed by a single surgeon at a center with around-the-clock robotic coverage. A team of nurses, OR technicians, and other staff members have acquired extensive training and experience to be able to handle these difficult cases. Owing to the challenges with setting up an efficient robotics program, the results of this study may not be generalizable to newly founded programs or inexperienced surgeons. It is essential to ensure communication between administrations, surgeons, and staff as well as adequate coverage to reproduce similar results. Multicenter studies, representing a more diverse surgeon population, are needed. Other study limitations include the lack of patient-reported outcomes and the lack of long-term follow-up outcomes determining definitive recurrence rates.

In conclusion, rEIHR is a feasible option for experienced surgeons within a capable robotics program. Patient selection is imperative to maximize this technique's utility.