In the present study, splenic injuries were found to be most common in the third decade of life and tended to affect more males than females. Similar demographic observation was also reported by other authors [2, 7, 11, 13, 15, 16]. This group represents the economically active age and portrays an economic lost both to the family and the nation and the reason for their high incidence of splenic injuries reflects their high activity levels and participation in high-risk activities. The fact that the economically productive age-group were mostly involved demands an urgent public policy response. Male predominance in the present study is due to their increased participation in high-risk activities. Identification of risk taking behavior among trauma patients has potential significance for the prevention of injuries.
Most patients in this study sustained blunt splenic injuries, which is comparable with other studies [7, 13, 15] but in contrast with other studies [9, 20] in which penetrating splenic injuries was the most common mechanism of injury. The high incidence of blunt splenic injuries in this study can be explained by the fact that those patients who had blunt splenic injuries were mostly involved in road traffic crash, a common feature of increased motorization in this environment. Road traffic accidents have been reported to be the commonest cause of blunt splenic injuries in most studies as supported by the present study [7, 11, 13, 15, 17]. In contrast to our findings, one study reported fall from height as the most common cause of splenic injuries . High incidence of road traffic accidents in our study may be attributed to recklessness and negligence of the driver, poor maintenance of vehicles, driving under the influence of alcohol or drugs and complete disregard of traffic laws. Improvement in road conditions, prevention of overloading of commuter vehicles, maintenance of vehicles and encouraging enforcement of traffic laws will decrease the frequency and extent of these injuries.
Despite the fact that injury-arrival time did not significantly affect the outcome of our patients in term of length of hospital stay and mortality, the author of the present study still believe that prolonged injury-arrival time contributes significantly to high morbidity and mortality among patients. Early presentation to hospitals and definitive treatment of these injuries has been reported to reduce mortality and morbidity associated with the disease [7, 11, 13].
In the present study, none of our patients had received any pre-hospital care at the site of injury and majority of them were brought in by relatives, friends, Good Samaritan or by police who are not trained to care for trauma patients. Only 2 patients were brought in by ambulance. Similar observations have been noted in other studies in developing countries [13, 15, 17]. The lack of advanced pre-hospital care in our environment coupled with ineffective ambulance system for transportation of patients to hospitals are a major challenges in providing care for trauma patients and have contributed significantly to poor outcome of these patients due to delay in definitive management.
The pattern of associated injuries in this study is in agreement with findings from other studies done elsewhere [13, 22]. The presence of associated injuries is an important determinant of the outcome of splenic injury patients . In the present study, the presence of associated injuries was found to be significantly associated with both mortality and length of hospital stay (morbidity). Early recognition and treatment of associated injuries is important in order to reduce mortality and morbidity associated with splenic injuries.
In the present study, more than 75% of patients had grade III and above splenic injuries which is agreement with other studies in developing countries [2, 11, 13, 15]. Carlin et al  found that the need for splenectomy was most significantly correlated with higher grades of splenic injury as supported by the present study.
The prevalence of HIV infection in the present study was 9.3% that is higher than that in the general population in Tanzania (6.5%) . However, failure to detect HIV infection during window period may have underestimated the prevalence of HIV infection among these patients. The high prevalence of HIV infection in our patients may be attributed to high percentage of the risk factors for HIV infection reported in the present study population. This implies that health care workers who care for these patients are at high risk of HIV transmission due to frequent contact with body fluids starting from the Accident and Emergency department to wards and in operating theatres. Thus, all trauma health care workers in this region need to practice universal barrier precautions in order to reduce the risk of exposure to HIV infection.
In recent years the policy of spleen's conservation at operation has been established due to its important role in cellular and humoral immunity and the danger of overwhelming sepsis in asplenic patients [10–14].
The recognition that patients without a spleen have an increased risk of death from overwhelming infection, led surgeons to consider methods of splenic preservation and with the introduction of the CT scan, non-operative management became popular and then predominant . Today, 90% of blunt pediatric splenic injuries and about 60-70% of adult ones are managed non-operatively in the West and other developed countries [15, 17, 23]. Criteria used to select patients for non-operative management of splenic injuries described in the literature include hemodynamic stability on admission, grade of splenic injury, amount of haemoperitoneum seen on CT scan, age less than 55 years, ability to elicit reliable physical signs on serial physical examination, limited blood transfusion requirements, and exclusion of other injuries that may require laparotomy . However, non-operative treatment of splenic injury patients remains a challenge for Africa. It is clear that as long as non-operative management is dependent on the availability of CT scanning, it cannot be offered to most injured Africans as only a tiny minority of injured Africans have access to CT scanning. Splenorrhaphy appears a better alternative. However, its success depends on operator experience and most African surgeons are unlikely to have at their disposal the technical material, like fibrin glue or dexon mesh, which makes splenorrhaphy more successful [27, 28]. In the present study, more than 80% of patients were treated operatively and the majority of patients underwent splenectomy. Similar treatment pattern was observed in other studies [2, 13, 17, 22]. High incidence of splenectomy in our study is attributed to the large number of patients with higher grades of splenic injury and low rate of splenorrhaphy in our study may be attributed to the lack of technical material, like fibrin glue or dexon mesh, which makes splenorrhaphy more successful. Also, unlike in western countries where patients present within few hours of injury and in relatively stable clinical state [15, 17, 23, 26], most of our patients presented to the A & E department in poor clinical state necessitating emergency laparotomy. The developing nature of our health system and haemodynamic instability of these patients on presentation makes operative management inevitable. We also noted that the time of operative intervention in our review showed an increase in the night-time splenectomy rate and the fact that most of the emergency surgery at night is performed by junior surgeons who may be unfamiliar with splenic salvage techniques may have also contributed to increased rate of splenectomy. On the other hand, in the patients with lower grades of splenic injury that had operative intervention it was due to other visceral injuries. Adequate clinical assessment, vigorous resuscitation, committed monitoring and co-operation between nursing staff and patients give good results when non-operative treatment is adopted using clinical parameters as a guide .
Lack of dedicated trauma centres for caring of trauma patients is a major problem in our community and the intensive care unit (ICU) at our hospital is unable to cope up with a large number of trauma patients as a result majority of patients are still admitted and managed in general surgical wards which are not well equipped in managing trauma patients. In the present study, ICU admission was influenced by injury grade, amount of haemoperitoneum, transfusion requirements, presence of coagulopathy, associated injuries or presence of co-morbidity.
The presence of complications has an impact on the final outcome of patients presenting with splenic injuries as supported by the present study. Splenic injuries are commonly associated with other injuries and these may complicate the management and affect the outcome . The pattern of complications in the present study is similar to what was reported by others [13, 17]. Early recognition and management of complications following splenic injury is of paramount in reducing the morbidity and mortality resulting from these injuries.
The length of hospital stay has been reported to be an important measure of morbidity among trauma patients. Prolonged hospitalization is associated with an unacceptable burden on resources for health and undermines the productive capacity of the population through time lost during hospitalization and disability . The overall length of hospitalization for both survivors and non-survivors in our study were found to be higher than that reported by other authors [17, 22]. This can be explained by the presence of severe trauma patients and large number of patients with associated injuries.
The overall mortality rate in this study was higher than that reported elsewhere [13, 22]. Factors responsible for high mortality in our study included advanced patient's age, associated injuries, trauma scores, grade of splenic injuries, admission systolic blood pressure ≤ 90 mmHg, estimated blood loss > 2000 mls, HIV infection with CD4 ≤ 200 cells/μl and presence of postoperative complications. Addressing these factors responsible for high mortality in our patients is mandatory to be able to reduce mortality associated with these injuries.
Post-splenectomy vaccination against encapsulated organisms is highly recommended for all splenectomised patients for trauma before their discharge from hospital, with re-vaccination every 5-10 years and additional antibiotic prophylaxis to compensate for the documented occasional vaccination failure [30, 31]. However, in our environment, the majority of patients post splenectomy fail to attend the follow-up clinic, making further management in those patients problematic. For these reasons, every attempt must be made for splenic salvage. This observation calls for training of junior surgical staff in methods of splenic salvage (splenorrhaphy). In the present study, none of our patient received post-splenectomy vaccination probably due to lack of availability of vaccines. This makes prevention of overwhelming post-splenectomy infection in our setting more problematic. Post-vaccination health education should therefore be given to all splenectomised patients regarding the risk, the importance of prompt diagnosis and treatment of infection, and the need for strong compliance with anti-malarial prophylaxis.
Self discharge by patient against medical advice is a recognized problem in our setting and this is rampant, especially amongst trauma patients . Similarly, poor follow up visits after discharge from hospitals remain a cause for concern. These issues are often the results of poverty, long distance from the hospitals and ignorance. Delayed presentation, lack of Focused Assessment using Sonography in Trauma (FAST) and irregular availability of CT scan (due to breakdown or inability of patients to afford), unavailability of interventional radiology, inadequate ICUs, limited vaccination, discharge against medical advice, and the large number of loss to follow up were the major limitations of this study. Also, since our duration of follow up was relatively short, we could not estimate the long term outcome of both surgical and non-surgical management of splenic injuries. However, despite these limitations, the study has provided local data that can be utilized by health care providers to plan for preventive strategies as well as establishment of management guidelines for patients with traumatic splenic injuries. The challenges identified in the management of patients with splenic injuries in our setting need to be addressed, in order to deliver optimal trauma care for the victims of splenic injuries.