Medical Therapy
The trend in management of splenic injury continues to favor nonoperative or conservative management. This varies from institution to institution but usually includes patients with stable hemodynamic signs, stable hemoglobin levels over 12-48 hours, minimal transfusion requirements (2 U or less), CT scan injury scale grade of 1 or 2 without a blush, and patients younger than 55 years. For instances in which patients have significant injury to other systems, surgical intervention may be considered even in the presence of the previously noted findings. Patients on anticoagulants, such as warfarin, and antiplatelet drugs, such as clopidogrel, are clinically considered to be at an increased risk for delayed bleeding, but this has not yet been confirmed in the surgical literature.
Recombinant factor VIIa has been used to avoid surgery in a pediatric patient, but in light of both the cost of the drug and the lack of randomized clinical trials, it should be used only in extreme circumstances where the risk of surgery outweighs the risk of massive thrombosis. [14]
A retrospective analysis by Scarborough et al compared the effectiveness of nonoperative management with immediate splenectomy for adult patients with grade IV or V blunt splenic injury. The study found that both approaches had similar rates of in-hospital mortality (11.5% in the splenectomy group vs 10.0%); however, there was a higher incidence of infectious complications in the immediate splenectomy group. The rate of failure in the nonoperative management was 20.1% and symptoms of a bleeding disorder, the need for an early blood transfusion, and grade V injury were all early predictors of nonoperative management failure. [15]
Interventional radiology
Splenic angioembolization is increasingly being used in both stable responders and transient responders for fluid resuscitation under constant supervision by a surgeon with an operating room on standby. Femoral artery access with embolization of the splenic artery or its branches can be accomplished with gel foam or metal coils. Such treatment requires intimate cooperation between the trauma surgeon and the interventional radiologist. Not all hospitals will have the proper facilities for such treatment, and any surgeon contemplating splenic angioembolization for a patient should first make sure the hospital interventional radiology suite and personnel are set up for rapid response at any hour of the day.
Surgical Therapy
Surgical therapy is usually reserved for patients with signs of ongoing bleeding or hemodynamic instability. In some institutions, CT scan–assessed grade V splenic injuries with stable vitals may be observed closely without operative intervention, but most patients with these injuries will undergo an exploratory laparotomy for more precise staging, repair, or removal. Adult surgeons may be more likely to operate in cases of splenic injury but less likely to transfuse than their pediatric surgical colleagues. [16]
Emergency celiotomy for hemoperitoneum with suspected splenic injury is performed through a midline abdominal incision. Subcostal or chevron incisions do not provide the opportunity to easily explore the lower abdomen for a hemorrhage site and cannot be performed as rapidly as a midline incision under emergency circumstances. Intestinal and mesenteric injuries may be missed, or they may be difficult to repair appropriately with subcostal incisions.
The splenic ligamentous attachments are taken down sharply or bluntly to allow for rotation of the spleen and the vasculature to the center of the abdominal wound and to identify the splenic artery and vein for ligation. Medial rotation also makes exposure of the hilum of the spleen easier and allows for possible identification of the splenic artery bifurcation. Once the splenic artery and vein are identified and controlled by ligation, the short gastric vessels are identified and ligated in similar fashion.
Ligating the splenic artery first, followed by the splenic vein, has the theoretical advantage of allowing some conservation of intrasplenic blood. In an emergency life-threatening situation, the amount of blood conserved is not worth the extra time it may take to isolate the vessels. Drains are typically unnecessary unless concern exists over injury to the tail of the pancreas during operation.
In less emergent situations, splenorrhaphy is the preferred method of surgical care. Multiple techniques are described in the literature, but they all attempt to tamponade active bleeding either by partial resection and selective vessel ligation or by putting external pressure on the spleen via an absorbable mesh bag or sutures. Both "make it yourself" and commercial products are available for this purpose. In patients with capsular injury, the electrocautery or argon beam coagulator device may provide adequate hemostasis and allow for splenic preservation.
A retrospective analysis by Wu et al compared the use of radiofrequency ablation (RFA) plus suture repair for splenic preservation with traditional splenic preservation surgery in 129 patients with traumatic splenic rupture. For the 35 patients receiving RFA plus suture repair, the mean time of operation was shorter (79 min ± 22 min vs 119 min ± 26 min); there was less bleeding during surgery (115 mL ± 67 mL vs 235 mL ± 155 mL); and there was less need for intraoperative transfusion (14% vs 36%). The RFA group also had significantly less postoperative bleeding and shorter hospital stays (7.1 days ± 1.4 vs 11.7 days ± 2.8). [17]
Preoperative Details
As most operations for splenic injury are a result of patient instability, standard emergency protocols are instituted, including obtaining 2 wide-bore (16F or larger) IVs for vascular access, 4-6 units of blood for surgery, nasogastric or orogastric tubes for decompression, and a Foley catheter to monitor urine output. Extensive blood work or coagulation profiles are rarely helpful in the emergent setting.
Intraoperative Details
Good communication with the anesthesiologist minimizes the chances for iatrogenically induced problems. Opening the midline fascia on entry into the belly often results in decreasing pressure on the damaged spleen and increased bleeding with hypotension. Keeping the anesthesiologist informed of surgical progress and actions can minimize potential complications of this nature. In most trauma situations, all 4 quadrants of the abdomen are packed with laparotomy pads, which are removed as the search for the bleeding site commences. Presence of a splenic injury on CT scan does not preclude the potential of a bleeding mesenteric tear, consequently, all patients should have a thorough examination of the abdomen—even if preoperative studies show an isolated splenic injury.
Postoperative Details
The postoperative course is usually 5-14 days, depending on associated injuries. Recurrent bleeding in the case of splenorrhaphy or new bleeding from missed or inadequately ligated vascular structures should be considered in the first 24-48 hours. The author's practice is to maintain a nasogastric tube on low intermittent suction for 48 hours to minimize the risk of a ligature failure on short gastrics with a distended stomach. Other authors prefer to suture ligate the short gastric vessels and to keep a nasogastric tube on low continuous suction to avoid this problem.
Patients should also be evaluated for immunizations against Pneumococcus species as a routine of postoperative management. Some authors and some centers also routinely vaccinate for Haemophilus and Meningococcus species. Various authors suggest immunization should be administered anywhere from 24 hours after injury to 2 weeks, citing studies of the improved physiologic response from vaccination after the immediate postoperative period. This must be weighed against the possibility of loss of follow-up care and missing the vaccination entirely. The author's practice is to immunize all patients prior to discharge.
Follow-up
The US Centers for Disease Control and Prevention (CDC) recommends revaccination with pneumococcal vaccine after 4-5 years one time only. A third booster is not recommended because there is no proof it improves protection from postsplenectomy sepsis, but there is proof that it may cause serious adverse effects. Splenic function is difficult and expensive to measure. Unfortunately, little current data exist regarding the efficacy of surgical treatment, whether operative or conservative.
Patients should be warned about the increased risk of postsplenectomy sepsis and should consider lifelong antibiotic prophylaxis for invasive medical procedures and dental work. Although the lifelong incidence of postsplenectomy sepsis has been estimated to be 0.03-0.8%, the mortality rate of those developing the complication approaches 70%. Adequate education of the signs and symptoms of pneumococcal infection should be stressed.
Complications
Complications of nonoperative care include delayed bleeding, splenic cyst formation, and splenic necrosis. Complications of splenorrhaphy include rebleeding and thrombosis of the residual spleen as well as complications related solely to the laparotomy.
Complications of splenectomy include bleeding from short gastrics or splenic vessels and the most feared but most rare complication, infection by encapsulated organisms such as Pneumococcus.
Material used for compression wrap of the spleen in splenorrhaphy is often woven and may mimic bubbles in an abscess on postoperative CT scans. Gel foam used for angioembolization may also falsely mimic an abscess on CT scans. Communication with the radiologist about the presence of splenic wrapping material on any postoperative CT scans will decrease the chance of this false-positive result.
Accessory splenic tissue and reimplantation of splenic tissue have never been reliably proven to minimize the risk of postsplenectomy sepsis. Once the spleen has been removed, patients should be considered to be at risk for encapsulated organism infections for the rest of their lives. Shatz et al noted improved postoperative response to immunization at day 14, with subsequent studies showing no further improvement at day 28. [18, 19]
Angioembolization of the spleen can result in noninfectious-related febrile events, sympathetic pleural effusions, and left upper quadrant abscesses. Femoral arteriovenous fistulas and iliofemoral pseudoaneurysms have also been reported. [20, 21]
Posttraumatic splenic pseudocysts are being reported more frequently now that nonoperative management has become the norm. [22] Optimal management is still unknown but probably requires partial or complete splenectomy to minimize morbidity and mortality.
Splenic abscesses and pancreatitis with sterile abscesses are being reported more frequently with Gelfoam embolization and with more proximal embolization procedures. [23, 24]
Thrombocytosis with platelet counts above 1 million/mm3 have been linked to thrombotic vascular events such as deep vein thrombosis, pulmonary embolus, or occlusive stroke. Although very little good data exist, many surgeons treat persistent thrombocytosis with a daily baby aspirin.
Pancreatic injury, pancreatitis, subphrenic abscess, gastric distension, and focal gastric necrosis have also been reported after both angioembolization and splenectomy for trauma.
Outcome and Prognosis
Recent multi-institutional studies by the Eastern Association for the Surgery of Trauma demonstrate that mortality from splenic injury still occurs, even in Level 1 trauma centers. Overall, outcome from grade 1-2 splenic injuries remains excellent but not perfect, and outcome worsens as the injury grade increases.
Prognosis is usually excellent, but those patients left asplenic by their injuries and surgery increase the risk of fatal and debilitating infection for the remainder of their lives.
Numerous papers have recently emerged in the literature comparing the practice and the outcome in different levels of trauma centers and comparing trauma and nontrauma centers. [25, 26, 27]
The risk of complications or failure of nonoperative management appears to be worse in patients older than 55 years, and women older than 55 years are significantly more likely to fail nonoperative management with an increased mortality.
Multisystem injury or concomitant liver, pancreas, or bowel injury increases the likelihood of splenectomy. Improved splenic trauma care and salvage rates can be shown in both trauma centers and nontrauma centers, though treatment pattern differences are evolving. Operative treatment with isolated injury is more likely at low-volume centers, but overall salvage rates for nonoperative management are similar between low- and high-volume centers.
Isolated splenic injury is more likely to have nonoperative or interventional radiologic management in a trauma center, but observant management is also more costly in these centers. Patients with multisystem injury in informal and formal trauma systems are more likely to be transferred to a trauma center, and splenic salvage rates in these patients are less than with isolated injury.
Future and Controversies
Improvements in diagnostic technology, such as helical CT scanners and portable ultrasound, will go far to diagnose and stratify risk in patients with splenic injury. Future multi-institutional trials and data collection may make it possible to better identify those patients at risk for persistent bleeding and to minimize the need for operative intervention and splenectomy in all but a few patients. Improvements in knowledge of immunology may lead to more effective immunizations for patients who are asplenic and further minimize their risk of deadly infection.
Increased availability and ease of access to interventional radiologic equipment and personnel, especially in rural hospitals, may salvage splenic injuries that previously required operative intervention and splenectomy.
The controversy over when to operate, when to embolize and when to observe will likely continue for the next millennium, but the debate will spur the continued development of diagnostic and evaluative tools, further minimizing morbidity and mortality caused by splenic injury.
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Hemisplenectomy (splenorrhaphy) with preservation of greater than 50% of splenic parenchyma.
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Intra-parenchymal blush observed on helical CT scan.
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Physical findings in postsplenectomy sepsis with peripheral thrombosis and disseminated intravascular coagulation (DIC).
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Grade 4-5 splenic laceration on helical CT scan.