Single port laparoscopic layered processing technique for large hysterectomy

Introduction

Background

Transumbilical single port laparoscopic hysterectomy is a cutting-edge minimally invasive surgical technique (1) performed through a 2–2.5 cm incision at the patient’s navel. This surgery belongs to a type of natural endoscopic surgery, which uses the navel, the “natural scar” of the human body, for surgery. There are almost no visible scars left after surgery, and it has outstanding minimally invasive and aesthetic features.

In terms of classification, this surgery belongs to a type of laparoscopic surgery, which is divided into transumbilical single port laparoscopic surgery (TU-LESS) and transvaginal single port laparoscopic surgery (V-NOTES). This surgical method aims to minimize incisions, minimize trauma, and achieve postoperative scarless outcomes.

In terms of clinical manifestations, multiple uterine fibroids or adenomyosis often cause uterine enlargement, leading to anemia or compression symptoms, and require uterine resection. Usually, uterine enlargement at 16 weeks or more is considered a large uterus (2). Traditional laparoscopic surgery significantly increases the difficulty of large hysterectomy and the incidence of complications (3). Open surgery is more traumatic, while umbilical single port laparoscopic technology provides a more flexible and minimally invasive solution.

Epidemiological characteristics show that a large number of women need to have their uterus removed each year due to gynecological diseases, and laparoscopic total hysterectomy has become one of the common surgical methods in gynecology (4). With the continuous advancement of surgical techniques and the improvement of instruments, transumbilical single port laparoscopic hysterectomy has been proven to be safe and feasible (5), and has the advantages of short postoperative intestinal function recovery time and mild pain.

In terms of natural history, the development of surgical techniques has gone through the evolution from laparotomy to laparoscopy, and then from porous to single pore, aiming to continuously optimize surgical outcomes, reduce patient pain, and meet the needs of female patients for more minimally invasive and aesthetically pleasing surgery.

Rationale

As a common gynecological surgery, hysterectomy is widely used to treat various uterine related diseases. The treatment methods mainly include single port laparoscopy, traditional laparoscopy, and open surgery.

Single port laparoscopic surgery has the advantages of minimal trauma, fast recovery, good aesthetics, and fewer complications (6). Due to having only one small hole, postoperative pain is mild, recovery time is short, and scars are not obvious. However, the surgeon’s field of view is limited, instruments conflict, and the difficulty of surgical operations is usually higher than that of traditional laparoscopy, especially for difficult and high-precision operations such as suturing, separation, and knotting. The learning curve is longer (7), which is its main disadvantage and requires the assistance of high-definition camera systems for operation, with higher technical requirements.

Traditional laparoscopic surgery also has the advantages of minimal trauma, fast recovery, and fewer complications, and has a wide range of indications. It can be used to treat diseases such as uterine fibroids and endometriosis. However, for large hysterectomy, traditional porous laparoscopic treatment of parametrial tissue is difficult. There are also relevant literature reports that single port laparoscopy has more advantages than porous laparoscopy for large hysterectomy with uterine volume greater than 20 weeks of pregnancy or weight greater than 500 g (8).

Open surgery has advantages in terms of treatment scope, efficacy, and safety, especially suitable for large uterine fibroids and complex pelvic diseases. However, the surgical trauma is significant, there is more bleeding, the recovery time is longer, and there will be longer surgical scars left in the abdomen, which affects aesthetics. In addition, open surgery may also increase the occurrence of complications such as infection, bleeding, intestinal obstruction, etc.

Layered technology provides a new solution for single port laparoscopic hysterectomy. Under single port laparoscopy, performing precise and difficult surgical operations in parallel or at small angles is more challenging than traditional multi-port laparoscopy, which demands higher surgical skills from the surgeon. It is necessary to constantly explore new methods and techniques different from multi-port laparoscopy, and gradually accumulate surgical experience in order to successfully complete precise and difficult operations such as suturing, knotting, and peeling. Therefore, this technology includes various new methods and surgical techniques different from porous laparoscopy. This technology involves opening the adjacent tissues of the uterus in layers, accurately identifying blood vessels, effectively stopping bleeding, and reducing bleeding; The flexible use of intrauterine devices and control rods in the intraoperative layering method can solve the problem of limited space, while the use of the cross method can reduce surgical interference and improve accuracy.

Objective

The single port laparoscopic layering technique aims to address multiple key goals and challenges in minimally invasive surgery. Its primary goal is to reduce surgical trauma, ensure surgical safety, reduce surgical difficulty, enter the human body through a single puncture hole, reduce postoperative pain and recovery time for patients, and improve cosmetic effects. This technology is particularly suitable for gynecological surgeries such as uterine fibroids and adenomyosis, as well as various surgeries in general surgery and urology.

During the surgical process, the main challenges faced by single port laparoscopic layering technology include cross interference between operating instruments, fine surgery in parallel or small angle states, limited surgical field due to large uterus, and difficulty in pulling and exposing the surgical site. To solve these problems, surgeons need to use disposable incision tension fixators (sets) produced by Beijing Aerospace Cardi Technology Development and Research Institute to ensure the sealing of the pneumoperitoneum and the smooth entry and exit of operating instruments. At the same time, the key to solving precise surgery is for the surgeon to use both surgical instruments and mirrors to create an operating triangle. The flexible use of the lifting cup and rod core can effectively solve the problem of space limitation and exposure difficulties caused by a large uterus during surgery. Layered technology is beneficial for exposing the parametrial blood vessels and ureters, protecting important tissues, reducing surgical complications, and solving the problems of reducing surgical difficulty and ensuring surgical safety.

The surgical technique diagram and video will cover the following content: firstly, display the incision position of single port laparoscopic surgery and the incision of the umbilical hole; secondly, describe the surgical steps in detail, including establishing pneumoperitoneum, exploring the abdominal cavity, separating tissues, removing the lesion site, and suturing the incision; finally, through high-definition videos, viewers can intuitively see the operational details during the surgery, such as how to use layering techniques to avoid tissue damage, how to accurately remove diseased tissue, and how to effectively stop bleeding.

Case presentation

The case is a 44-year-old female who complained of “continuous worsening of dysmenorrhea for 4 years and increased menstrual flow for 3 months”. Gynecological examination: The uterus has a spherical enlargement, such as that of a four-month-old pregnant woman, with a hard texture. Magnetic resonance imaging shows an increase in uterine volume, indicating adenomyosis with a hemoglobin level of 68 g/L. Diagnosed with adenomyosis and moderate anemia, the patient underwent a “single port laparoscopic total hysterectomy with bilateral salpingectomy and pelvic adhesiolysis adhesion separation surgery” under general anesthesia in a laminar flow thousand level operating room of a tertiary hospital. The surgery went smoothly, took 60 minutes, had a bleeding volume of about 20 milliliters, and removed a uterus weighing 1,690 g. After 8 hours post-surgery, the urinary catheter was removed, and the patient was able to move out of bed and exhale smoothly. The recovery was good, and on the first day post-surgery, the hemoglobin level increased to 90 grams per liter. The patient recovered and was discharged 4 days after surgery.

• Surgical approach: minimally invasive(laparoscope).
• Treatment goal: curative.

We present this article in accordance with the SUPER reporting checklist (available at https://gpm.amegroups.com/article/view/10.21037/gpm-24-27/rc).

Preoperative preparations and requirements

Patient preparation

• Improve preoperative examinations, such as blood routine, coagulation function, liver and kidney function, infectious diseases, electrocardiogram, ultrasound, and magnetic resonance imaging, to exclude surgical contraindications.
• Fully informed prior to surgery, as well as promoting and guiding the concept of accelerated rehabilitation surgery, informing patients and their families of relevant matters that require cooperation.
• Fasting for 6 hours before surgery, oral administration of 250 mL of 5% glucose injection 2–3 hours before surgery, and unconventional enema before surgery.
• Prophylactic antibiotics are administered intravenously 30 minutes before skin incision, usually after anesthesia induction.

Equipment preparation

One Olympus 30° electronic all-in-one mirror, one Tianjin Ruiqi Surgical Instruments Co., Ltd. ultrasonic knife, bipolar electrocoagulation forceps, unipolar electric hook, separation forceps, needle holder, tissue cutter, wire cutter, irrigator, surgical knife and handle, and one disposable incision tension fixator (set) produced by Beijing Aerospace Cardi Technology Development and Research Institute.

Surgical team

A highly experienced lead surgeon (standing on the left side of the patient), two assistants [one mirror operator (standing on the right side of the patient) and one uterus lifting operator], one equipment nurse, one mobile nurse, and two anesthesiologists proficient in general anesthesia performed the procedure in the Class 1000 operating room (required condition) of Urumqi Maternity and Child Health Hospital (a tertiary Grade A hospital).

Ethical statement

All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Written informed consent was obtained from the patient for the publication of this article and accompanying images and video. A copy of the written consent is available for review by the editorial office of this journal.

Step-by-step description

Step 1: routine preparation

The patient underwent general anesthesia, tracheal intubation, bladder lithotomy, and iodine disinfection of the umbilical incision. Two tissue clamps were used to clamp both sides of the umbilical area, and the umbilical area was lifted to make a longitudinal incision of about 2.5 cm in the middle of the umbilical area. The umbilical fossa was cut vertically into the skin, and subcutaneous tissue was cut layer by layer until the peritoneal layer was reached. A single hole PORT was inserted, the inner and outer rings were fixed, CO₂ gas was injected, and the pneumoperitoneum pressure was maintained at 10–12 mmHg. A 30° Olympus endoscope was then placed.

Step 2: place the palace cup

Before placement, rinse the vagina with 0.125% iodine solution, select the appropriate cup body according to the size of the cervix, screw the thread of the lifting cup into the cervical canal for fixation, and place it in the middle of the uterine cavity using a central guide rod.

Step 3: remove the fallopian tube and ovarian intrinsic ligament

Due to the large size of the uterus, when removing the fallopian tubes and ovarian ligaments, the uterus will be pulled down to make more surgical space available; Removing the fallopian tubes to 2 cm beside the uterus and cutting the circular ligament (Figure 1) and ovarian intrinsic ligament 2–3 cm away from the uterine angle can avoid unnecessary bleeding.

Figure 1 Remove the left round ligament at a distance of 2 cm from the parametrial to avoid damaging the parametrial blood vessels.

Step 4: open the broad ligament and ovarian intrinsic ligament

Layered incision of the anterior lobe of the ligament to make the parametrial tissue thinner, facilitating the recognition of the ureter and blood vessels, avoiding damage to the ureter and fully coagulating the blood vessels, and coagulating the ovarian intrinsic ligament in the direction close to the ovary (Figure 2) to avoid damage to the ascending uterine spiral blood vessels adjacent to the uterus and reduce bleeding.

Figure 2 Open the anterior lobe of the left broad ligament.

Step 5: push down the bladder

Adjust the uterine lifting device to position the uterus in the center of the pelvic cavity (if the enlarged uterus affects the operation, the core of the lifting device can be retracted into the cervical canal), push down the bladder, find the gap, separate the bladder cervical ligament, and push down the bladder to about 2 cm below the edge of the lifting cup (Figure 3).

Figure 3 Open the peritoneal reflection.

Step 6: nake the blood vessels adjacent to the uterus

Layered along the severed circular ligament, open the anterior lobe of the broad ligament to the cervical isthmus, and then open the posterior lobe of the broad ligament to reach the sacral ligament, exposing the parametrial blood vessels (Figure 4).

Figure 4 Open the left broad ligament layer by layer to identify the structure and avoid damaging the ureter.

Step 7: electrocoagulation closure of uterine blood vessels

Above the rim of the uterine cup, bipolar electrocoagulation of uterine blood vessels is performed in the uterine isthmus to avoid the risk of thermal damage to the ureter (Figure 5). The main and sacral ligaments are cut along the rim of the uterine cup.

Figure 5 Exposed left uterine blood vessels.

Step 8: hysterectomy

The monopolar electric hook is used to cut the vaginal vault along the rim of the lifting cup to remove the uterus (Figure 6) and place the uterus into the surgical band and use a surgical blade to “peel an apple”. Cut three sides and leave one side. Cut the uterus into strips with a diameter of about 2 cm and remove them.

Figure 6 Circumcision of vaginal fornix.

Step 9: suture the vaginal stump

Rinse the pelvic cavity with 0.125% iodine solution, block the vaginal opening with sterile gauze, establish pneumoperitoneum, and continuously suture the vaginal stump with 2-0 absorbable suture, with a suture spacing of about 1 cm, in 2 layers (Figure 7).

Figure 7 Suture vaginal stumps with 2-0 absorbable thread.

Step 10: umbilical shaping surgery

Take out a single port, suture the fascia layer continuously with a 2-0 absorbable suture, then suture the fat layer continuously, and finally use a 3-0 absorbable suture to invert and suture the skin layer in three layers to restore the anatomical shape of the navel (Figure 8) and avoid the occurrence of umbilical hernia.

Figure 8 The umbilical region of the patient one month after surgery.

Postoperative considerations and tasks

Prophylactic antibiotics should be administered within 24 hours after surgery, and patients should be encouraged to get out of bed and remove the catheter 8 hours later; Postoperative pain is mild and analgesics may not be used; Starting from 4 hours after surgery, it is recommended to replenish water appropriately. If there is no discomfort, a liquid diet can be consumed 6–8 hours after surgery, and a regular diet should be maintained 24 hours later. Perform postoperative rehabilitation exercises and be discharged as soon as possible. Recheck the healing of vaginal stump and navel once a week and once a month after discharge.

Compared with traditional open surgery, the postoperative recovery time of single port laparoscopic giant hysterectomy is similar, but the advantages are obvious. Traditional open surgery requires a significant amount of trauma, and it takes 24–48 hours for intestinal peristalsis to return to normal after surgery. Patients can only eat after this time, which not only prolongs their fasting time and increases physical consumption, but also causes severe postoperative incision pain due to the larger surgical incision, affecting the patient’s rehabilitation experience and the development of postoperative activities.

Tips and pearls

• Surgical area treatment: preoperative and postoperative flushing of the surgical area and pelvic cavity with 0.125% iodine solution can reduce the probability of infection.
• Fine operation guarantee: using mirrors with both hands to operate in a triangular area to assist in fine surgery.
• Application of layering technology: when removing fallopian tubes and ovaries, the uterus is pulled and the broad ligaments are layered to facilitate the operation, protect tissues, and expose blood vessels and ureters.
• Application of lifting cup and core: place the lifting cup and screw it into the cervical canal. During operation, remove the core as needed to increase uterine mobility.
• Uterine vascular treatment and uterine removal method: during hysterectomy, electrocoagulation of uterine blood vessels on the inner edge of the cup is used to prevent ureteral thermal injury; take the uterus with a large retrieval bag and cut it through the vagina or navel in a “peeling apple” manner.
• Stitching and knotting techniques: single port laparoscopic vaginal stump suturing and knotting have techniques, and the cross method and bending forceps auxiliary techniques are practical and efficient, overcoming the problem of limited instrument operation and achieving the effect of multi-port laparoscopic surgery.

Discussion

In the practice of single port laparoscopic hysterectomy, multiple key operational steps play a decisive role in the success of the surgery.

• Surgical area treatment: before surgery and after hysterectomy, thoroughly rinse the surgical area and pelvic cavity with a 0.125% concentration of iodine solution. Practice has shown that this measure can significantly reduce the probability of postoperative infection and have a positive effect on ensuring surgical prognosis.
• Fine operation guarantee: surgical operators use both hands to control instruments and use mirrors as support points to construct a small operation triangle area, which enables precise completion of various fine operations and lays a solid foundation for the smooth progress of surgery, helping to improve surgical quality and efficiency.
• The application of layered technology: when removing fallopian tubes and ovaries, the uterus is pulled down, and after removing the round ligament, the uterus is horizontally pushed up, which can expand the surgical operator’s field of view and provide sufficient operating space. At the same time, using layered techniques to treat broad ligaments can not only effectively avoid damage to important tissues, but also facilitate the exposure of parametrial blood vessels and ureters, further enhancing the safety of surgery.
• The application of lifting cups and core rods: lifting cups and core rods have flexible and important application methods in surgery. When placing the uterine cup, it needs to be rotated into the cervical canal to provide a fixing effect and can be used to pull down and push up the uterus. When pushing down the bladder and rotating the fornix, the core of the lifting cup should be withdrawn into the cervical canal, which can increase the mobility of the uterus and avoid adverse effects on surgical operations due to the large volume of the uterus.
• Uterine vascular treatment and uterine removal method: during the process of hysterectomy, electrocoagulation of uterine blood vessels on the inner side of the cup edge is adopted, which can effectively prevent thermal damage to the ureter and is of great significance in protecting the normal function of the urinary system. In addition, when removing the uterus, first place it in a large retrieval bag, and then use the “apple cutting” method through the vagina or navel to remove three sides while keeping one side. During the removal process, rotate while cutting, and finally cut the uterus into a long strip with a diameter of about 2 cm for removal. During this process, care should be taken to avoid cutting and ensure the complete removal of the uterus.
• Suture knotting technique: suture knotting is the difficulty in single port laparoscopic surgery. The video related to this study demonstrates a smooth process of suturing and knotting the vaginal stump, achieving the effect of porous laparoscopic surgery, fully demonstrating practical suturing and knotting techniques (Video 1). Specifically, when sewing knots, the cross method is used, such as using the left hand to apply force to the lower right and the right hand to apply force to the upper left. This operation method can avoid mutual interference between the two hands and is more labor-saving. Moreover, cleverly utilizing the curvature of the pliers during knotting, the thread is clamped at the tip of the pliers, combined with a reasonable pulling direction, to form a natural coil after the thread returns, which helps to smoothly complete the suturing and knotting operation and improve the overall quality of the surgery.

This surgical technique has significant advantages. Firstly, it combines minimally invasive and aesthetic features. Compared to traditional open surgery, single port laparoscopic surgery has less trauma, less pain, faster recovery, and a concealed incision, which is beneficial for improving patients’ psychological and quality of life. Secondly, precise operation ensures safety. The comprehensive application of multiple technologies ensures precise operation, reduces the incidence of complications, and improves surgical safety. Thirdly, improve visibility and space. The layered treatment of uterine push-pull and broad ligament creates better surgical conditions in the limited space of single port laparoscopy.

However, this technology also has limitations. The technical difficulty is high, the learning curve is long, and the skill requirements for surgeons are high, which limits the promotion and application. The instrument enters the abdominal cavity through a single hole, resulting in crowded space and poor flexibility, making it difficult to handle complex situations and increasing surgical risks. In addition, the surgery time may be longer, and the cost of special instruments may increase, affecting their popularity at the grassroots level.

To improve this technology, training can be conducted on a simulation trainer to shorten the learning curve. Develop finer, more flexible, and multifunctional instruments, optimize the design of the lifting cup and shaft core. Detailed preoperative planning to improve surgical efficiency.

Looking ahead to the future, single port laparoscopic hysterectomy is expected to usher in new developments. By leveraging technologies such as 5G, remote surgery and medical resource sharing can be achieved, promoting the development and improvement of this technology globally and bringing more innovation and change to the field of gynecological surgery.

Conclusions

We have successfully performed single port laparoscopic hysterectomy using layered techniques, ensuring precision and safety. The use of layered techniques in handling adhesions, exposing the field of view, and treating blood vessels effectively avoids bleeding and injury. The postoperative patient recovered well without any complications. The successful application of layered technique in this case demonstrates its feasibility and superiority in single port laparoscopic hysterectomy, improves surgical accuracy, reduces time and patient pain, and has significant clinical value. In summary, this surgical method is safe, effective, and feasible, providing valuable experience for clinical work. Further exploration and research will be conducted to improve surgical quality and patient satisfaction.

Acknowledgments

The video was awarded the second prize in the Fourth International Elite Gynecologic Surgery Competition (2024 Masters of Gynecologic Surgery).

Footnote

Provenance and Peer Review: This article was commissioned by the editorial office, Gynecology and Pelvic Medicine for the series “Award-Winning Videos from the Fourth International Elite Gynecologic Surgery Competition (2024 Masters of Gynecologic Surgery)”. The article has undergone external peer review.

Reporting Checklist: The authors have completed the SUPER reporting checklist. Available at https://gpm.amegroups.com/article/view/10.21037/gpm-24-27/rc

Peer Review File: Available at https://gpm.amegroups.com/article/view/10.21037/gpm-24-27/prf

Funding: None.

Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://gpm.amegroups.com/article/view/10.21037/gpm-24-27/coif). The series “Award-Winning Videos from the Fourth International Elite Gynecologic Surgery Competition (2024 Masters of Gynecologic Surgery)” was commissioned by the editorial office without any funding or sponsorship. P.C. reports support for attending the Final of the 10th China Obsterics and Gynecology Network Surgery Video and the 2024 West China International Symposium on Gynecological Tumors and Female Pelvic Floor Dysfunction Disorders, and patents of an adjustable inflatable position pad for gynecological tumor surgery under laparoscopy, a single port laparoscopic myomectomy device and a self-made simple single port laparoscopic channel system. P.C. is also the member of the Chinese Anti Cancer Association, the Obstetrics and Gynecology Branch of the China Association for the Promotion of International Exchange in Healthcare, the Gynecological Endocrinology Professional Committee of the Chinese Association for the Promotion of Traditional Chinese Medicine Research on the Integration of Traditional Chinese and Western Medicine, and the Executive Director of the Integrated Chinese and Western Medicine Branch of the Chinese Society of Traditional Chinese Medicine Information. M.K. reports patents of a laparoscopic surgical peeler with attractive function, and serving as member of the Gynecological Endocrinology Professional Committee of the Chinese Association for the Promotion of Traditional Chinese Medicine Research on the Integration of Traditional Chinese and Western Medicine and Director of the Distance Education Branch of the Chinese Society of Ethnic Medicine. J.W. reports patens of a uniform mixing device for medicinal liquids with temperature control function, a leak proof medication delivery device for obstetrics and gynecology and a user-friendly gynecological vaginal irrigator. J.W. also serves as Director of the Distance Education Branch of the Chinese Society of Ethnic Medicine. The authors have no other conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. All procedures performed in this study were in accordance with the ethical standards of the institutional and/or national research committee(s) and with the Helsinki Declaration (as revised in 2013). Written informed consent was obtained from the patient for the publication of this study and accompanying images and video. A copy of the written consent is available for review by the editorial office of this journal.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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