Splenic trauma is the most common abdominal organ injury in abdominal trauma, accounting for about 40-50%. As early as 1911, the famous surgeon Kocher clearly stated in the textbook of surgical surgery that “splenectomy is not harmful to the body and that this organ should be removed when the spleen is injured”. Therefore, for a long time, splenectomy was performed when splenic trauma was diagnosed. It was not until 1952 that King and Shumaker reported five cases of fatal postoperative infection in 100 children who had splenectomies, three of whom died; in 1969 Whitaker reported the first fatal infection after splenectomy in an adult. Since then, the problem of post-splenectomy infections has gradually gained attention and various types of splenoprotective surgery have emerged. In the last 20 years, with the continuous research on the morphology and function of the spleen, the development of diagnostic techniques, the advancement of monitoring tools, and the improvement of treatment, the management of splenic trauma has evolved from total splenectomy to the deliberate pursuit of splenic preservation to the current stage of selective splenic preservation.
Grading of splenic trauma
The development of a reasonable clinical grading method for splenic trauma is an important guide to the selection of the correct surgical treatment plan. The clinical grading of splenic trauma has not yet been satisfactorily standardized at home and abroad; Shackford first graded splenic injury in 1981, and Call and Scheele divided splenic injury into 4 grades on this basis in 1986. The American Association for the Surgery of Trauma (AAST) developed the following grading of splenic injury in 1994.
Domestic scholars, mostly based on Call and Scheele grading, have proposed their own grading method since the 1990s [1, 2]. The Sixth National Splenic Surgery Symposium held in Tianjin in September 2000, the Splenic Surgery Group of the Chinese Society of Surgery formulated the criteria for grading the degree of splenic injury, specifically: Grade I: subperitoneal rupture of the spleen or mild injury to the peritoneum and parenchyma, with the length of splenic laceration ≤ 5.0 cm and depth ≤ 1.0 cm as seen by surgery. Grade II: Splenic laceration with total length >5.0cm and depth >1.0cm, but the splenic hilum is not involved, or the splenic segment is vascularly damaged. Grade III: Splenic rupture with injury to the splenic hilum or partial severance of the spleen and damage to the blood vessels of the splenic lobe. Grade IV: extensive rupture of the spleen, or damage to the splenic hilum and splenic arteriovenous trunk [3]. We believe that the above criteria are simple, practical, and include the entire structural damage of the spleen from the peritoneum to the parenchyma and from the vascular branches to the trunk, which is in line with our national conditions and is a guide for clinicians, especially primary care physicians, in the standardization of treatment and the selection of surgical procedures.
Treatment selection of splenic trauma
In general, the diagnosis of splenic trauma is not difficult based on history, symptoms and signs, supplemented by abdominal puncture, ultrasound, CT and other examinations, but attention should be paid to misdiagnosis and omission due to unknown injury history, multiple trauma and unconsciousness. Once the diagnosis is clear, how to choose the correct management plan is the central part of clinical work.
As mentioned earlier, splenectomy has been the only option for treating various types of splenic rupture for a long time due to the one-sided belief that “the spleen is not a vital organ” and that it has a rich blood supply, fragile tissue and is difficult to stop bleeding. However, modern splenic research has proved that the spleen has various functions such as blood storage, hematopoiesis, blood filtration, blood destruction, immune regulation, synthesis of coagulation factors, phagocytosis of malaria parasites, anti-tumor, etc. Especially, the recognition of the risk of aggressive infection after splenectomy has led surgeons to gradually develop the concept of “spleen preservation” and to establish the principles of splenic trauma management: (1) save life first and preserve the spleen second [4]; (2) the younger the patient, the more spleen-preserving surgery is preferred; (3) the quality and quantity of the preserved spleen must have adequate splenic function; (4) choose the appropriate spleen-preserving procedure or combine several procedures according to the type and degree of injury.
1.Conservative treatment of splenic trauma
For some patients with subperitoneal or superficial splenic rupture, if there is not much bleeding, stable vital signs, and no combined injuries, conservative treatment can be performed under close dynamic observation. Specific indications are: ① Grade I according to AAST classification (or our splenic surgery group grade); ② age less than 50 years; ③ no combined injuries of other intra-abdominal organs; ④ except pathological splenic rupture, no coagulation abnormalities; ⑤ hemodynamic stability, blood transfusion volume not more than 400-800ml, ⑥ imaging (ultrasound, CT) dynamic monitoring of the hematoma does not expand, blood accumulation does not increase, or splenic artery (6) no or minimal contrast spillage on imaging; (7) conditions for intermediate surgery and intensive care are available. Among the above indications, hemodynamic stability is the most important element and is a prerequisite for deciding whether to perform conservative treatment. If hemodynamic stability can be maintained after a small amount of blood and fluid transfusion, other indications can be relaxed appropriately. In recent years, with the accumulation of experience, it has been found that some AAST grade II splenic injuries can also be cured non-operatively, and the age can be relaxed to 55 years or even higher. However, most scholars believe that it is still necessary to take a cautious approach to conservative treatment of splenic trauma, especially in small and medium-sized hospitals where monitoring means and resuscitation measures are not complete, and should not be overly advocated, and even in large hospitals where conditions are available, the indications should be strictly controlled because, in terms of saving lives, surgical treatment of splenic trauma is more certain and less risky than conservative treatment. The main measures of conservative treatment include: absolute bed rest, fasting, water, gastrointestinal decompression, blood and fluid transfusion, application of hemostatic drugs and antibiotics, etc. After about 2-3 weeks, the patient can get out of bed for light activities, and should avoid strenuous activities for 3 months after recovery.
2.Splenic preservation surgery
There are many methods of splenic preservation surgery, and the operator needs to make a specific choice according to the condition of the splenic trauma, the condition of the hospital, and the experience of the operator himself. In order to effectively maintain the normal function of the spleen, it is necessary to preserve no less than 1/3 of the normal spleen volume and good blood flow.
(1) Local physical or bioadhesive hemostatic techniques.
For those grade I splenic trauma with small and shallow fissures, gelatin sponge can be used to fill the rupture and compress the hemostasis after opening, and bio-gel adhesion hemostasis, microwave or argon coagulation hemostasis, splenic rupture bundling, mesh hemostasis, etc., which are reliable, simple and feasible treatment methods if the indications are properly selected.
(2) Suture repair.
Suture repair can be performed for grade I and II splenic ruptures with small ruptures that do not injure large blood vessels. The reason is that the splenic rupture is mostly transverse in shape and in the same direction as the large blood vessels in the spleen, not injuring the interlobar vascular trunk but the trabecular vessels. Therefore, suture repair is a safe and effective technique for hemostasis in patients with small splenic ruptures, where local physical or biologic adhesive hemostatic techniques are ineffective, and where there are no hemodynamic changes. However, this procedure depends on the patient’s intraoperative bleeding, the presence of other combined injuries and emergency surgical conditions. For patients in critical condition, with poor suture hemostasis and poor surgical technique, suture repair is not emphasized; otherwise, the patient’s life may be endangered by excessive blood loss.
(3) Ligation or intraoperative embolization of the spleen artery.
There are few clinical reports on the use of splenic artery ligation to treat splenic rupture. Some animal experimental studies have found that splenic artery ligation reduces bleeding from the splenic rupture wound, and bleeding stops after about 6-10 minutes. Postoperative biochemistry, immunology, scans, and arteriography showed no abnormalities or only temporary changes. Splenic artery ligation can decrease the pressure of splenic artery by 50 mmHg -60 mmHg, and the spleen becomes smaller and more resilient, which facilitates suturing and achieves more effective hemostasis. Ligation of the splenic artery does not usually cause splenic infarction because its blood flow can be compensated by the vessels of the surrounding ligaments. However, some studies have found that after ligation of the splenic artery trunk, the spleen is unable to remove pneumococci from the bloodstream and the patient is still at risk of developing a fatal infection. Intraoperative splenic artery embolization is rarely used in clinical practice because the extent of embolization is not easily controlled and there is a possibility of ectopic embolism with splenic infarction and infection. Although some successful experiences have been accumulated in the treatment of splenic trauma in recent years, the incidence of complications such as bleeding and infection is still high, and it is necessary to embolize the main trunk of the splenic artery to effectively stop bleeding, so its therapeutic value is still controversial.
(4) Partial splenectomy.
It is suitable for grade II or partial grade III splenic rupture with good blood flow to the spleen. The human spleen has 2-3 main lobes of the internal splenic artery branches, which are segmentally and terminally distributed, and there are relatively avascular zones between each lobe, marking the plane of splenic parenchyma resection. The splenic artery is the main scaffolding structure of the splenic parenchyma, suggesting that splenic rupture due to blunt trauma occurs most often between the two segmental arteries. The procedures for partial splenectomy include partial (partial), subtotal, or segmental splenectomy. It is mainly suitable for those who have severe rupture of a part of the spleen that is difficult to preserve. After opening the abdomen, the blood vessels of the injured part of the spleen are free ligated according to the distribution of the splenic segments, so that a clear demarcation line between normal and tissue becomes visible, and interrupted or interlocking sutures are ligated with a large needle and absorbable sutures through the edge of the normal splenic tissue at the demarcation point. Finally, a piece of large omental tissue is used to cover the cut surface. In recent years, we have used microwave tissue coagulation technique to form a coagulation zone at the intended resection line of the spleen, and then used a scalpel to separate and remove the traumatized or diseased part of the spleen, which is a simple method with precise hemostasis and satisfactory results, and has a popular application. Some studies have shown that the residual spleen tissue from most partial splenectomies can complete the immune function of the spleen [6].
(5) Laparoscopic splenoprotection.
Laparoscopy can not only clarify the diagnosis, but also facilitate the determination of the degree of injury. A conventional carbon dioxide continuous pneumoperitoneum with pressure maintained at 12-14 mmHg is used to first understand the extent of splenic injury and lesions of other intra-abdominal organs, and then the blood around the spleen is aspirated to reveal the spleen. For grade I and II ruptures, hemostasis can be achieved by bio-gel spraying, electrocoagulation and hemostatic sponge filling; for grade III splenic rupture, a comprehensive hemostasis method should be used, which can be done by filling the rupture with vascularized omentum and then suturing. If there is no bleeding, a drainage tube can be placed around the spleen to end the operation [7]. In our opinion, laparoscopic splenoprotection is mainly suitable for patients with closed abdominal injuries who are young in age, have mild splenic injury as determined by clinical manifestations and relevant examinations, are hemodynamically stable, and have no compound or multiple organ injuries. It should be emphasized that it is unwise to use laparoscopic splenic preservation to stop bleeding in grade IV or higher splenic rupture with severe injury and large bleeding volume, and the success rate of the operation is extremely low.
(6) Autologous splenic tissue transplantation.
Not all splenic trauma can be successfully treated by splenoprotective means, and splenectomy is still necessary to control bleeding and save lives in about 60% of splenic trauma. In cases of simple splenic injury where the whole spleen cannot be preserved, splenic comminution, splenic portal lacerations, splenic portal clots and failed splenic repair, combined with less contaminated intra-abdominal parenchymal and cavernous organ injuries, grade III and IV non-pathological splenic rupture, autologous splenic transplantation can be performed to compensate for splenic function [8]. Splenic tissue transplantation can be divided into various types such as intra-retinal capsule, intra-splenial bed, intra-peritoneal folds, intra-rectus abdominis, and even splenocyte portal vein or intrahepatic injection. Among them, intra-retinal capsule transplantation is the most commonly used method, in which the excised spleen is cut into thin slices of a certain size, usually about 2.0′2.0′0.5 cm in size, fixed in the omental vascular rich area, and then the free edge of the omentum is folded to make an omental capsule with several stitches around it. It is important to note that splenic tissue transplantation, although it can perform some immune function, is much less functional than a normal spleen. Therefore, in patients with ruptured spleen trauma, the spleen should be preserved as much as possible under the premise of preserving life, and autologous splenic tissue transplantation should be considered only for patients who must undergo splenectomy.
3.Total splenectomy
Compared with splenectomy, splenectomy is relatively complicated and there is a possibility of postoperative rebleeding. Under the principle of “save life first, save spleen later”, total splenectomy is a safer surgical option.
The indications for total splenectomy are
①Type IV or higher splenic rupture.
②Elderly patients.
③Critical injury and need to finish the operation as soon as possible.
④Splenoprotection still cannot effectively stop the bleeding.
⑤ The operator is not skilled or inexperienced in splenoprotective surgery and is not sure.
In conclusion, splenic trauma is more common in clinical practice. I believe that in addition to the above classification scheme, the treatment should be based on the degree and extent of injury, the presence of combined injuries, the age, physical condition and financial ability of the injured person, the experience of the operator and the medical environment, etc., and must follow the basic principle of “saving life first”. We must follow the basic principle of “saving life first” and choose the most appropriate treatment for the patient.