Traumatic right diaphragmatic rupture with hepatothorax in Ghana: two rare cases

A rare case series of traumatic right diaphragmatic rupture with hepatothorax in Ghana is reported. The first case involved a middle-aged man who sustained a penetrating chest injury following an unprovoked attack by a wild bull. The second case was a young woman who sustained a blunt chest injury after being knocked down by a moving vehicle whiles crossing the road. Both presented with ruptured right diaphgramatic rupture and had to undergo repair through thoracotomy after stabilization and the two had been well one year after surgery without any complications or sequelae.


Introduction
Traumatic injuries of the diaphragm remain an entity of difficult diagnosis despite having been recognised early in the history of surgery. Traumatic diaphragmatic injury may result from a penetrating injury or blunt thoracoabdominal injury and results in communication between the pleural and peritoneal cavities. The injury can occur either on the right or on the left hemidiaphragm, however the left diaphragm is more commonly involved, as its weakest point is located on the left posterolateral aspect of the pleuroperitoneal membrane. On the other hand, the right diaphragm is able to withstand greater intra-abdominal pressure gradients due to the shock absorptive protection by the liver, therefore traumatic right diaphragmatic injury is a rare entity. The organs that most commonly herniate into the thorax include the stomach, spleen, colon, small bowel and liver. Their presentation can be immediate or delayed and they are often in combination with other more severe injuries especially the right side injuries. The diagnosis is missed among those admissions in up to two thirds of cases. Various modalities of imaging studies such as X-ray, sonography, multislice computerized tomography scan, magnetic resonance, thoracoscopy, laparoscopy and fluoroscopy are available for diagnosing diaphragmatic injury but the diagnostic image of choice is multislice computerized tomography.
Delay in presentation can lead to complications and increased mortality.

Case 1
History: a 44 year old male cattle farm help and an alcohol abuser but a non-smoker with no significant past medical or surgical, chest or abdominal trauma history, was referred to the Accident and Emergency Centre of the Komfo Anokye Teaching Hospital from a peripheral hospital, two days after having been attacked by a bull in the chest. Patient was swang about in air three times while still attached to the bull, dropped onto the floor and stomped on in the right hemithorax and right upper abdomen before the bull was chased off by fellow workers. He presented to a peripheral hospital soon after the incident with a complaint of chest pain and was given analgesics, antibiotics and tetanus prophylaxis after evaluation and had his chest wounds dressed. Imaging could not be done at the facility. He is said to have momentarily improved, but continued to have right chest and abdominal pains and was thus referred to the Komfo Anokye Teaching Hospital on the third day of injury. On arrival he was conscious and alert and well oriented with SPO2 of 96% on room air, respiratory rate of 26 breaths/minute, heart rate of 124 beats/minute with a blood pressure of 137/57mmHg. His random blood sugar (RBS) was 8.6mmol/l, haemoglobin level of 10.9g/dl and had a temperature of 360°C. Systemic review was significant for shortness of breath, chest pain, cough (non-productive) and abdominal pain. He was talking clearly and there were no concerns for the airway and cervical spine.
Chest expansion was limited on the right hemithorax with extensive subcutaneous emphysema from the jugular notch to the umbilicus and reduced breaths sound. There was a 2x2cm deep wound on the right anterolateral chest wall which was not communicating with the right pleural space. He had right upper abdominal guarding and tenderness.
There were no significant pelvic and musculoskeletal findings except a clean 5x2cm laceration on the posterolateral aspect of the left thigh.
He had warm peripheries with normal capillary refill time.

Discussion
Diaphragmatic ruptures can occur with both blunt and penetrating trauma which can be associated with intrathoracic herniation of abdominal viscera [1]. Following blunt thoracoabdominal trauma, diaphragmatic rupture is reported in 0.8-3.6% of patients [2].
Right-sided diaphragmatic rupture occurs in approximately 5-20% of all diaphragmatic injuries [2]. Left diaphgramatic ruptures are more common than the right because the right hemidiaphragm is mechanically stronger than the left and is also partially protected by the energy-absorbing liver. It therefore requires a greater force for injury [3,4]. The mechanisms of rupture include a sudden increase in intra-abdominal pressure throughout the abdomen with the relatively weak unprotected left diaphragm tearing from the force or avulsion of the diaphragm from the chest wall, rib fracture fragments directly penetrating the diaphragm and direct injuries from impalement, stab or gunshot wounds [3,4]. The physiopathological consequences of ruptured diaphragm affect mainly the cardiopulmonary system due to reduced function of the diaphragm, lung compression, mediastinal shift leading to impaired venous return to the heart and subsequently low cardiac output. Thoracic signs include decreased breath sounds, fractured ribs, flail chest, and signs of haemothorax or pneumothorax.
Auscultation of bowel sounds in the chest is pathognomonic, especially in left-diaphgramatic ruptures due to thoracic intestinal herniation [1].
Abdominal signs include abdominal swelling, guarding, tenderness and absence of bowel sounds depending on the extent of injury.
Occasionally physical examination can be relatively normal [5]. If diagnosis is delayed to months or years after the injury, symptoms are generally less severe, and are due to the space occupying lesion from the thoracic intestinal herniation (dyspnoea, orthopnoea, respiratory distress), and partial or complete obstruction of herniated abdominal contents (nausea, vomiting, abdominal, and chest pain).
Our first patient sustained a penetrating injury to the chest from the horn of the bull leading to the rupture whereas the second patient Page number not for citation purposes 4 sustained the injury form a blunt chest injury from the knocked down, however both presented with more chest signs than abdominal signs.
The preoperative diagnosis of traumatic diaphragmatic rupture is difficult especially from penetrating injury [2,3]. This was the situation with our first patient who was diagnosed on the third day of injury.  Figure 3 whereas only chest x-ray was used in the second patient as shown in Figure 4. Chest x-ray has a relatively low sensitivity for diagnosing diaphragmatic ruptures with only about 17-40% of the patients having suggestive signs [1]. The chest x-ray signs include abdominal gas patterns in the chest, nasogastric tube in the chest, blurring and elevation of the hemidiaphragm, mediastinal shift and compression atelectasis of the lower lung lobe [3]. There may also be pleural effusion (haemothorax), obliteration of the costophrenic angle and diaphragmatic contour distortion. These signs were shown in the chest x-ray of the two patients as shown in Figure 1 and Figure 4. The published diagnostic CT sensitivity and specificity of right hemidiaphragm rupture is 50-90% and 90-100% respectively [1][2][3].
MRI offers identical information to that of helical CT but with better direct coronal and sagittal images, however, restricted patient access, cost and unsuitability for emergency patients make MRI less preferable [1]. is extensive loss of tissue [1,7]. The mortality associated with the right traumatic diaphragmatic rupture within the first 24hours is reported to be 0-31 % [1,7].

Conclusion
Traumatic right diaphragmatic rupture is an extremely rare entity, given the protection afforded by the liver and therefore the diagnosis of right diaphragmatic rupture requires a high index of suspicion.
Although, chest X-ray is the most common initial imaging tool, CT scan is the preferred imaging modality. Immediate surgical repair via a thoracotomy approach to repair the diaphragm after reduction of the herniated abdominal contents constitutes the recommended acute surgical management.