Rib fractures are a major traumatic injury. They can result in significant complications for patients and so require careful assessment and management to minimise this.
Rib fractures are usually the result of fairly significant blunt thoracic trauma. This is a fairly common feature of major trauma, thus rib fractures are found in around 10% of these patients. Problems arise from:
Underlying lung injury
Mechanical alteration to breathing
Sequelae of above
Rib fractures are notoriously painful. The requirement for ongoing breathing prevents the injury being rested, but the pain response can commonly limit the extent of breathing that a patient can do. Deep breathing and coughing are frequently challenging. The result of this, especially when combined with underlying lung contusion, is atelectasis and impaired sputum clearance. This increases the risk of subsequent pneumonia, as well as their own impairment of gas exchange.
The force required to break ribs is generally adequate to result in significant underlying lung injury as well. This is particularly true of extensive fractures and flail segments. This contused lung will experience an inflammatory response, as well as localised haemorrhage and potentially necrosis. All of these processes impair gas exchange.
These changes all contribute to impaired gas exchange and increased risk of infective complications. The gas exchange is primarily one of V/Q matching, and so hypoxia predominates, with an increased respiratory rate usually compensating to maintain normocapnia. However, this may not be the case in extensive injury.
A flail segment is defined as a fracture of 2 or more contiguous ribs in 2 or more locations. This creates a portion of the thoracic wall that is essentially free-floating. This can move paradoxically with inspiration and further impair respiratory mechanics. Rib fractures on either side of the sternum have the potential to create a situation where the sternum is free floating. The rib cage also provides some stabilising effect on the thoracic spine, and loss of this can make a potentially stable spinal fracture more unstable.
This will be part of a major trauma approach and only the specifics relating to the rib fractures will be described here. The presence of rib fractures may be felt likely through the mechanism of injury, and thus special attention in the examination directed towards them. Pain on inspiration, as well as general localised pain may be reported by awake patients.
Examination may find:
Crepitation on palpation
Paradoxical chest movement in flail segment
This may include:
A CXR may be performed in some scenarios, but may not identify all rib fractures. Other major injuries may also be detectable this way.
Most patients with the mechanism of injury to break ribs will have a CT scan as part of their investigations. This can provide more detailed information on the nature of the injuries.
Assessment of the severity of the rib fractures is an important guide to subsequent management . Key factors which have been shown to correlate with the severity are:
Number of fractures (not just number of ribs fractured)
Bilateral > unilateral
A Rib Fracture Score has been described to provide a composite representation of this: Rib Fracture Score = (Breaks x Sides) + Age factor
An increasing score denotes increasing severity and may be used to guide management e.g. analgesic choices. However, it hasn’t been shown to have a strong predictive validity and local sites may have varying guidance for management.
Fractures of the 1st and 2nd ribs or scapula have required significant energy, and extra caution should be maintained if these injuries are identified.
As noted, these injuries are commonly part of a major trauma picture, and so need consideration alongside other injuries. The components of rib fracture management specifically can generally be considered as:
As noted, these are notoriously painful injuries. Obtaining effective analgesia is important to allow more effective coughing and deep breathing and thus reducing the risk of the vicious circle of pathophysiological effects. As with other forms of pain, a ladder of analgesic options can be envisaged:
Surgical fixation may also be a component of care that has an important role in analgesia in some cases.
Simple analgesia options are generally straightforward and well understood. Paracetamol is a very benign starting part, and NSAIDs can be considered in the absence of contraindications because of their effectiveness. A gabapentinoid may be added at a later stage to assist with reducing opioid requirements.
Opioids will often be required in addition to simple analgesia. These will also be of a scale, ranging from weak opioids, through to oral opioids (regular and breakthrough, through to an opioid PCA. Side effects should be anticipated and managed appropriately (antiemetics, laxatives).
Regional anaesthetic options may be considered in cases of severe fractures with significant symptoms or who are struggling with other analgesic options. Techniques that have been employed include:
Serratus anterior block
This is probably the standard of care for severe rib fractures when other analgesia options are inadequate. They are particularly useful in patients with fractures that are:
Resulting in resp compromise
There is good evidence of improved respiratory and, more importantly, clinical patient outcomes:
Better tidal volumes
Reduced pneumonia rates
They need appropriate patient selection however, as some of the other features of multisystem trauma may make their insertion challenging or even contraindicated.
The level of insertion should aim to be that of the middle fractured rib. The volume of local anaesthetic will be somewhat dependent on the extent of rib fractures, as this the distance that it needs to spread. The choice of local anaesthetic agent (concentration and use of opioid) will be more dependent on local practices. Close monitoring is required for the duration of the time that it is being used to assess for complications.
These are an alternative to thoracic epidural analgesia. A single catheter is able to provide unilateral cover for around 6 ribs. Additional catheters can be sited, with caution needing to be given regarding the safe amount of local anaesthetic. This reduced effect area may make them a less desirable option for some patients. However, there is evidence demonstrating comparable results compared with epidurals, whilst avoiding some of the adverse features. The limited epidural spread should reduce the risk of both sympathetic blockade, and the motor blockade associated with epidurals. A large volume of LA is recommended to aid the appropriate spread (bearing in mind toxic doses) with 40ml of 0.25% levobupivacaine being an example described for a unilateral block. Infusions via a catheter can then be continued for up to 7 days, with the patients able to mobilise with the catheter in.
This is another regional technique that has a few advantages over the others described. Injection of local anaesthesia into this plane can block the intercostal nerve innervation of the anterior hemithorax of levels T2-9. There are very few contraindications, compared to the other techniques above, making this an option in some of the cases where an epidural or paravertebral may not be possible e.g. vertebral fractures. Bilateral blocks can be performed and catheters may be inserted and used for up to 7 days. It is also a technically easier block than the others.
Intercostal blocks can provide effective analgesia for up to 24 hours, but are limited by their locality. This means that multiple injections are needed to help with multiple fractures, each being associated with the risk of bleeding, infection and pneumothorax.
Intrapleural blocks are no longer usually employed due to their relative ineffectiveness (positioning nature, LA coming out of drain) and high systemic uptake of LA.
The surgical fixation of ribs has come in and out of fashion over the years. The challenges compared to the fixation of other bony injured include:
The challenging shape (conical and twisting)
Repeated stress of ventilation
Surgical access - can require painful incisions
However, it is increasingly recognised that some patient groups may benefit from surgical fixation, including:
Intubated patients with
Deteriorating respiratory status with flail segment (non-intubated)
Thoracotomy for other indications
The evidence is relatively light, but suggests that appropriate fixation results in:
Lower rates of pneumonia
Reduced critical care admissions/fewer ventilator days