Chest trauma is one of the major contributors of morbidity and mortality among trauma patients. Accordingly, out of the total of admitted chest trauma patients, the magnitude of chest trauma mortality was 7.2% (95% CI: 4.8%, 10%). This finding is consistent with the studies done in united Arab Emirate (7.2%)(15), Iran 7.1% (27), Yemen (5.5%)(18) western UP (6.4%)(3), and Nigeria (5.4%)(11).
However, the finding of the present study is higher than the studies done in Syria (1.8%)(24), Chit wan Nepal (3%)(28), Tanzania (4.7%)(10), Nigeria (2.56%)(26) and Sudan (2%)(20).
The possible justification for being higher might be due to discrepancy in sample size, difference in study population as the above populations; ; difference in early arrival of the patient in the Hospital (97% arrived within 24 hours in Nepal study while 82.8% in this study); disparity in associated injury (36% in Syria while 53.5% in this study); divergence in development of complication (10.7% in Sudan while 17.3% in this study); difference in prehospital care (21.3%,in Tanzania,whereas15% in this study) even though presence of pre-hospital care did not significantly associate with mortality in this study. Difference in the study setting and health care system as the above countries (Syria is developed countries).
On the other hand the finding of this study is lower than the studies done in England (35.6%)(2), India(20.84%)(21) and Tanzania (24.4%)(8). The possible justification for being lower might be due to difference in sample size (large sample size) in the above studies. Study in India and Tanzania showed that 95% and 61.3% of the study participants have associated injury respectively while 53.5% in this study; difference in study design (unlike this study cohort follow up in Tanzania); difference in study time, study setting Unlike in this (four years) study the above studies undergone chart review for many years (11 years in England).
In this study age, associated injury, complication and time of arrival were significantly associated with chest trauma mortality.
The current study revealed that there was a positive relationship between being old age and mortality of chest trauma patients. This is supported by the study done in Germany, Turkey, Massachusetts and England(29–31).As the age increase the patient comes with preexisting medical condition and diminished physiologic reserve (immunity) that inability to compensate for trauma and susceptible to pulmonary deterioration and often affected by other complications such as pneumonia(32).As age increase the thoracic cage is more prone to costal and sternal fractures resulting in severe injuries to internal organs, which may be lethal(33).
Associated injury and mortality of the study participants were found to be positively associated. This is similar with the studies done in Uganda(34), Nigeria(11), Tanzania(10), and Qatar(35) stated as the presence of associated injuries were significantly associated with mortality in chest trauma patients. This might be due to the reason that associated injuries may increase the risk of complications like hemorrhage, infection and others.
The result of this study also showed that there was a positive relationship between having complication after chest trauma (pneumonia, wound sepsis, atelectasis and hypovolumic shock) and mortality of study participants. This is similar with studies done in Tanzania(10) and Uganda(34)stated as presence of complications due to chest injury was significantly associated with mortality in chest trauma patient. This might be due to the reason that patients having complications after chest trauma might relatively have poor prognosis than others who did not have complications.
Being late arrival in the Hospital after injury and death of chest trauma patients were positively associated. This is supported by studies done in Nigeria stated that delayed presentation with injury beyond 24hrs was significantly associated with mortality in chest trauma victim (11). This might be due to the reason that as chest trauma patient delayed for presentation at Heath institutions after an event, the patient might be exposed for Hemorrhage, complications (sepsis) and others may lead the patient for death.
Limitation
Shortage of similar studies carried out in Ethiopia makes the comparison and discussion difficult.
Since the data was secondary /chart review/, there was missing of variable in the chart. (religion, marital status, occupation, time of treatment started, alcoholic behavior, smoking habit)