12.3 Orthopaedic approach to the multiply injured patient

Injury is a leading cause of morbidity and premature death in the young. The initial treatment of seriously injured patients has improved with advances which include: minimizing the time at the accident scene; a more structured training for those involved in front-line trauma management; designated trauma centres with appropriate and adequate support from allied specialities. These improvements, combined with the early initiation of resuscitation protocols and early emergency interventions, have been attributed to improved patient survival after serious injury.

Orthopaedic trauma produces a systemic stress response, which is related to the degree of initial injury. Clinical outcome is determined by the magnitude of response both to the initial injury and its subsequent surgical management. The term ‘second hit’ has been applied to the process whereby an injured and physiologically vulnerable patient is exposed to further trauma as a result of the surgical management of his injuries. Therefore, the initial orthopaedic management of a seriously injured patient must balance between limited physiological tolerance and the optimal volume of fracture stabilization surgery initially required.

A number of physiological processes should be considered in managing the multiply injured patient. Hypoxia, hypovolaemia, electrolyte imbalance, pulmonary and systemic embolization, coagulopathy, and inflammation all evolve over the initial hours and days after injury. The processes overlap and can operate in synergy to produce indirect end-organ hypoxia and subsequent tissue damage. The pathophysiology is also affected by the injury severity with direct associated injuries (for example, blunt trauma to the chest), which can render the patient more vulnerable to the effects of initial fracture management. A patient’s individual response to injury can also vary considerably, with acute respiratory distress and major organ dysfunction being the most serious sequelae.

The stabilization of pelvic fractures which are causing haemodynamic instability is an obvious priority. Isolated adult femoral shaft fractures can also result in a range of blood loss from 300–1300mL and transfusion rates of up to 40% with a direct correlation to the degree of preoperative haemorrhage. Blood loss and transfusion requirements are higher after multiple lower extremity fractures and there is an increased frequency of acute respiratory distress.

The direct effects of hypovolaemia are to reduce end-organ tissue perfusion and oxygen delivery. This results in impaired aerobic metabolism and subsequent tissue damage. Indirect effects include the activation of platelets and the production of a hypercoagulable state. Proinflammatory cytokines are also upregulated during the early phase after injury as a direct result of hypovolaemia with overproduction being related to increased rates of acute respiratory distress, multiple organ failure, and mortality. Cytokines are acute-phase proteins implicated in the activation of the complement cascade and the expression of fibrinogen. Interleukin-6 (IL-6) is a predominantly proinflammatory cytokine secreted by macrophages and T lymphocytes. It has a relatively long half-life with a peak concentration that occurs 4–6h after injury and persists for several days. This makes it a potentially useful prognostic marker after injury where levels have been shown to correlate with mortality rate. In addition, excessive proinflammatory cytokine production stimulates the breakdown of muscle proteins and further contributes towards tissue damage after hypovolaemic shock.

The correction of hypovolaemic shock is paramount to any trauma resuscitation protocol. However, standard measurements of heart rate and blood pressure do not always accurately indicate adequate tissue and end-organ perfusion. ‘Oxygen debt’ and ‘occult hypoperfusion’ are terms which have been applied to the haemodynamically stable patient, who has persistently elevated lactate levels and a deficit in tissue oxygenation after trauma. This type of patient is inadequately resuscitated and has uncorrected metabolic acidosis. A twofold increase has been demonstrated in postoperative complications in patients undergoing early (<24h) femoral fracture fixation with elevated lactate levels (i.e. >2.5 mmol/L) that were not corrected prior to surgery. The complications involve a range of systems including respiratory (acute respiratory distress syndrome, ARDS), as well as an increased incidence of infection. Higher rates of multiple organ failure and respiratory complications have been demonstrated after major trauma in patients with persistent (>24h) and uncorrected metabolic acidosis. Such patients are more susceptible to the ‘second hit’ phenomenon caused by emergency surgery. Adequate haemodynamic and acid–base resuscitation is essential prior to surgery in order to optimize outcome and improve mortality after serious injury.

Fat embolus is defined as fat within the circulation and can occur with or without clinical sequelae. Most long-bone fractures produce a mild, asymptomatic, and transient hypoxaemia detectable on pulse oximetry. The severity of hypoxaemia is correlated to pulmonary fat embolic load and tends to be greater after high-energy trauma or multiple long-bone fractures. Subsequent episodes of hypoxaemia can occur after manipulative or operative procedures on the fractured extremity.

The clinical manifestations of fat emboli are usually explained on the basis of mechanical effects. Fat globules are forced into the venous circulation as a consequence of pressure changes within the medullary canal. They are then transported in the venous system to the right side of the heart and thereafter enter the pulmonary circulation where they obstruct small arterioles and capillaries. Systemic fat embolization can occur due to arteriovenous shunting of emboli through the pulmonary circulation. In addition, a patent foramen ovale can also predispose to systemic effects by allowing emboli to enter the left atrium directly and bypass the pulmonary filtration process.

However, fat emboli also produce ‘biochemical’ effects after trauma. Lipase enzyme stimulation and catecholamine production stimulate the conversion of benign fat to toxic free fatty acids which can potentially damage end-organ endothelial lining. These toxic products contribute to the stimulation of coagulative and inflammatory processes (systemic inflammatory response syndrome, SIRS), which form part of a patient’s systemic stress response after trauma.

Surgical procedures that instrument the medullary cavity are associated with increased intramedullary pressure and fat embolus production. Instrument design and surgical techniques have concentrated on reducing this fat embolic load. The use of unreamed nails, reamer aspiration irrigation systems, and intramedullary canal venting are all surgical techniques available to reduce the pulmonary and systemic fat embolic load during intramedullary long-bone fracture fixation.

Fat and bone emboli can enter the systemic circulation via a patent foramen ovale. Paradoxical embolization can also occur through arterial–venous shunts in the pulmonary circulation. Transcranial Doppler ultrasound has correlated shunt size to the volume of embolic material detected in the cerebral circulation. Chest injury is commonly associated; an altered pattern of pulmonary circulation caused by the chest injury may increase the degree of blood shunting within the pulmonary.

Trauma and subsequent surgery activates thrombogenic and fibrinolytic pathways within the pulmonary and systemic circulations. Increased perioperative levels of prothrombin fragments 1 and 2 and fibrin degradation products have been demonstrated in isolated femoral fractures treated with intramedullary fixation.

This activation and possible loss of coagulation control has been linked to the development of acute lung injury and other systemic complications after major trauma. Therefore a synergistic embolic and coagulative response can occur after trauma which can affect pulmonary function. The more severe clinical responses can produce a clinical picture similar to disseminated intravascular coagulation. Localized disseminated intravascular coagulation within the lung has been attributed to acute lung injury due to the production of microthrombi.

In the minutes that follow a traumatic event, the direct tissue damage and change in haemostasis produce an inflammatory response. This involves the activation of monocytes and granulocytes that produce pro- and anti-inflammatory mediators. The term systemic inflammatory response syndrome (SIRS) has been applied to the generalized inflammatory response to trauma. This initial proinflammatory response is produced predominantly from macrophages and is primarily involved in removing damaged tissue and beginning repair processes. This initial stress response is relatively short lived and the monocytes soon become deactivated and unable to respond to fresh stimuli. A compensatory anti-inflammatory response (CARS) is then activated with mediators directly linked to the development of immunosuppression after trauma.

Therefore this imbalance can result in a period of compromised immunity after serious injury. A more pronounced immunodepression is seen with increasing levels of haemorrhage and tissue damage. The clinical effects of this immune imbalance are an exacerbation of shock, increased fluid transudation into end-organ interstitial spaces, coagulative activation and a predisposition to infection. These processes are apparent in the days after injury and correspond to the scheduling time for many surgical procedures, which will involve further tissue trauma.

A recent development has been the use of pro- and anti-inflammatory markers in the prediction of patient outcome after serious injury. Elevated IL-6 levels have been demonstrated in the polytraumatized patient with further increases measured after intramedullary femoral fracture fixation.

Excessive release of proinflammatory cytokines appears to be central in the pathogenesis of complications such as acute respiratory distress. Amplified levels of proinflammatory cytokines IL-1β and IL-8 have been demonstrated from bronchoalveolar lavage samples in patients with high injury severity scores. However, there was no corresponding rise in systemic (serum) concentrations.

The accumulation of neutrophils and proinflammatory mediators has been demonstrated in the alveolar space during early acute respiratory distress. The alveolar space appears to be converted into an area of intense localized inflammation. Inflammatory cytokines can act as chemoattractants to draw neutrophils from the plasma into the interstitial space. This was demonstrated in a prospective clinical study, where neutrophils were isolated and examined from peripheral blood samples taken from healthy volunteers and from patients after major musculoskeletal trauma. The chemoattractant properties of IL-8 were demonstrated with enhanced neutrophil migration across porous tissue culture inserts in the injured group. The coupling of enhanced neutrophil migration with elevated IL-8 levels may be central to the development of pulmonary and other end-organ inflammation.

Care of patients who have sustained multiple injuries requires a team approach. During the initial phase in the Emergency Department this is usually coordinated by an accident and emergency consultant, with other specialties intervening in a coordinated and timely fashion, following ATLS protocol. The role of the orthopaedic team is to firstly assess for any musculoskeletal injuries that require urgent intervention. The haemodynamically unstable pelvis is an obvious example. Open fractures require antibiotic and tetanus prophylaxis with the application of a sterile dressing. Obvious skeletal deformity such as that caused by a dislocated ankle or long-bone fracture can also be reduced and temporarily splinted.

A careful secondary survey performed at this stage will often identify other orthopaedic injuries not identified during the initial Emergency Department assessment. Appropriate plain x-rays can be ordered to assess these areas, but in a timely fashion to minimize treatment delay. At this stage a list of injuries should be complied and effective communication with allied specialties will allow a hierarchy of injuries to be established. The most urgent life- or limb-threatening injuries should be dealt with first.

It is important to identify any logistical problems that may impede the surgical treatment plan. The optimal department for the patient’s continued care should be established with intensive care specialists involved at an early stage if required. The availability of theatre and the relative orthopaedic trauma experience of the available theatre staff should be ascertained. Good communication with regards to the type and availability of the appropriate surgical hardware required will save time and allow adequate theatre preparation time. Inform the theatre staff of the likely sequence of surgical procedures and whether simultaneous management of different injuries is being considered. The availability of a radiolucent table greatly eases simultaneous fixation of long-bone and pelvic injuries. The intramedullary stabilization of long-bone fractures without the need for skeletal traction in the multiply injured can also reduce operative time, but requires adequate experience and good surgical assistance.

The physiological status of the patient throughout surgery should be monitored with the help of the anaesthetist. Appropriate invasive monitoring should be instigated with the insertion of a central venous and arterial lines and use of a Swan–Ganz catheter. These give vital information regarding the true haemodynamic and metabolic status of the patient with pulmonary arterial pressure measurements being proportional to the degree of arterial hypoxaemia. The most urgent surgical procedures, such as the external fixation of an unstable pelvic fracture or the adequate tissue debridement of an open fracture, should be performed initially. Extremity injuries often require being redraped in order to ensure sterility. A few minutes of discussion before surgery in order to formulate a surgical plan can minimize the operative time. The management of contralateral upper and lower extremity injuries can be facilitated by a team approach with simultaneous fracture fixation, but requires adequate staff numbers. The floating knee can be stabilized with femoral and tibial intramedullary nails inserted through the same small incision in a retrograde and antegrade fashion respectively. Priority should also be given to injury types where bone, cartilage, and soft tissue damage is likely to progress with time. The dislocated shoulder or ankle may have been already reduced in the emergency department; however, a femoral head fracture/hip dislocation or displaced femoral neck or talar fracture are examples of injuries where a delay in treatment affects prognosis.

The Gustilo and Anderson classification system for open fractures is most commonly used and effectively describes the degree of soft tissue injury, periosteal stripping, and vascular injury. The vascularity and perfusion of damaged tissue should be assessed and allied specialties such as plastic surgery involved early. The wound should be minimally re-exposed and inspected as this may increase the contamination risk. Antibiotic prophylaxis reduces the incidence of infection and is usually prescribed for 3 days. The regimen can be altered depending upon the likely degree of contamination. Cephalosporins are most commonly administered with the addition of an aminoglycoside and penicillin (to cover Clostridium) in more contaminated wounds. Double antibiotic therapy is more effective specifically after type 3 open fractures.

A soft tissue debridement is only effective if it removes all necrotic and contaminated material. Serial debridement removes only tissue which is clearly necrotic on each operative visit. An immediate and more extensive ‘en bloc’ excision into viable tissue allows removal of all affected material and minimizes the infection risk of subsequent bone stabilization and reconstructive procedures.

An adequate excision of skin, subcutaneous fat, fascia, and muscle must be performed. Bone fragments contaminated or free from soft tissue attachments should also be removed. There is debate about the best type of lavage to use. Pulsatile lavage will not compensate for an inadequate tissue debridement and may obscure the tissue planes and cause secondary tissue damage. The use of normal saline or Ringer’s lactate with low pressure lavage should suffice after an adequate debridement.

The initial soft tissue and bone excision should not be compromised by concerns about subsequent tissue defects and wounds should not be closed under tension. Skeletal stabilization should then be performed after the initial debridement. If the initial soft tissue debridement was considered inadequate then a second debridement should be considered within 48h. Early plastic surgery input with regards to soft tissue reconstruction is vital. The reconstructive ladder describes the available soft tissue options which range from primary closure or a simple split skin graft, to pedicled or free flap transfers. Immediate reconstruction is recommended and has been shown to reduce complication rates and speed patient rehabilitation. Delayed reconstruction (>72h) after extremity trauma increases the incidence of flap failure, delays bone healing, prolongs hospital stay, and increases the number of subsequent operative procedures required.

The management of a haemodynamically unstable pelvis is a priority after serious injury. The mechanism of injury and accident details will often give an accurate guide to the most likely pattern of injury sustained. For example a rollover car vehicle accident is associated with a lateral compression (LC) pattern; a fall from a height would more likely produce a vertical shear (VS) fracture; forceful leg abduction and external rotation of the hemipelvis, (common after a motorcycle accident) can produce an anterior–posterior compression (APC) injury. Physical examination includes one gentle pelvic manipulation to assess stability and a careful secondary survey to exclude associated injuries with particular attention given to the spine and lower limbs. Urethral injuries occur in 15% of patients. The initial radiographs taken will include an anteroposterior radiograph of the pelvis which is useful in determining the type of pelvic injury. The pattern of fracture can predict the most likely associated injuries. APC patterns are associated with pelvic bleeding and damage to hollow viscera. LC injuries have a higher incidence of head and thoracic injury. Vertical shear fractures often damage the sacral plexus and have a higher incidence of neurological problems. A trauma computed tomography (CT) scan can be arranged in the haemodynamically stabile patient and gives useful additional information especially with regards to posterior ring integrity and the presence of blood in the pelvis. The primary ATLS survey establishes resuscitation and whether the patient is responding well, transiently or poorly to intravenous fluids. Haemorrhage into the thorax, abdomen, retroperitoneum, or from extremity injuries should be identified. An increased pelvic volume with the presence of hypovolaemia is an indication to apply a pelvic binder in the Emergency Department. External pelvic fixation should be applied prior to a laparotomy due to the tamponade effect provided by an intact abdominal wall. The open pelvic fracture should be assessed as to whether it involves the rectum and therefore risks faecal contamination. Haemorrhage from an open pelvic wound can be temporized by wound packing with skeletal stabilization of the pelvic injury. Wound management forms part of a secondary procedure with an adequate debridement and a temporary colostomy for faecal diversion.

If there is continued haemodynamic instability after pelvic skeletal stabilization then either pelvic angiography with embolization or pelvic packing is indicated. Controversy exists with regards to the optimal treatment method. Delayed embolization later than 3h after injury is associated with increased mortality rates. Good indications for arterial embolization in patients who have not responded to resuscitation and skeletal stabilization are: vascular ‘blush’ visualized on CT scan and an expanding retroperitoneal haematoma. Pelvic packing is a technique advocated for the exsanguinating and unresponsive patient and can form part of a damage control operative protocol.

Definitive pelvic fixation involves anterior symphyseal plating for displacements greater than 2cm. A vertically unstable posterior ring injury requires closed reduction and percutaneous screw fixation or direct open reduction with plates and screws.

The age, hand dominance, profession, previous injuries sustained, associated medial problems (e.g. diabetes), and drug history are all important factors to obtain once the life-threatening injuries have been stabilized. The time from injury allows an estimation of the ischaemic duration and likely tissue viability, whilst the mechanism and nature of the injury are indicators of the degree of tissue damage and contamination. Whilst circulation can be adequately assessed under an anaesthetic, motor and sensory function to the upper limb extremity should be assessed in the emergency department. This vital information should be obtained quickly and calmly with minimal distress or discomfort to the patient with adequate analgesia given prior to assessment. Plain radiographs should be obtained, with other useful diagnostic adjuvant being Doppler ultrasound and compartment pressure monitors. Preoperative planning should involve an estimation of the likely surgical time. This has implications with regard to the type of anaesthetic used (regional or general) and the application of a tourniquet.

After serious skeletal injury, limb revascularization is the first priority before soft tissue debridement and skeletal stabilization. Early intervention with vascular surgery aims to restore both arterial and venous blood supplies. Important considerations are:

Reconstructive options include: primary closure (immediate or delayed); skin grafts; local, regional, pedicle, and free flaps. Amputation can be considered if functional reconstruction is not possible. This decision may be subjective, but is best made after the combined good judgement of the surgical team rather than any one individual. Scoring systems such as the mangled extremity severity score (MESS) are less applicable to the upper limb.

Early skeletal stabilization of upper limb injuries allows early rehabilitation, facilitates nursing, and reduces patient discomfort and morbidity. Open reduction and internal fixation of long-bone diaphyseal fractures after polytrauma with dynamic compression plates and screws is standard. External fixation or intramedullary long-bone stabilization is less successful than in the lower limb with higher iatrogenic and soft tissue complication rates. Concerns with regards to increased infection and non-union rates after open fractures or operations through contused soft tissues should not alter the method of fracture fixation. Acceptable (<15%) rates of non-union and infection after fixation of open forearm fractures with good functional results have been demonstrated in the majority of patients. Bone shortening is a useful technique which can achieve a stable construct following extensive bone and soft tissue loss. This is well tolerated in the upper limb. Intra-articular fractures of the shoulder, elbow, and wrist require reduction and stabilization. Options include: splint immobilization; open reduction and internal fixation; arthroplasty and arthrodesis.

Tendon and nerve injuries are best managed by early reconstruction. The location of the injury (e.g. zone 2 flexor tendons), the extent of the surrounding soft tissue damage, and the patient’s associated injuries all influence outcome. Primary tendon repair restores anatomy with the ipsilateral palmaris longus tendon or long toe extensors being the most commonly used donor grafts if tendon substance has been lost. Although early reconstruction improves outcome, tendon transfer procedures are usually performed at a later stage once the patient has recovered and an accurate assessment of any functional deficits has been made. The key to successful rehabilitation is dynamic splinting whilst adequately protecting the tendon repair. Nerve reconstruction generally produces less satisfactory results even after direct repair in a clean and well vascularized environment. Nerves should be sutured without tension and if this cannot be achieved due to soft tissue damage, then nerve transposition or free non-vascularized grafts (e.g. sural nerve) for more extensive defects are commonly used options.

The initial patient assessment should determine patient age, pre-injury level of function, mechanism of injury, time from injury, and haemodynamic status. Associated injuries to the head, chest, abdomen, and pelvis should be documented. Peripheral nerve function and the vascular status of the lower limb are assessed, with specific injuries more likely to compromise neurovascular function. Examples include the dislocated hip which can affect sciatic nerve function and medial tibial plateau fractures which are associated with a higher incidence of popliteal vessel and common peroneal nerve injury. Sensation over the plantar aspect of the foot and the presence of pedal pulses (use Doppler ultrasound if required) should be determined in the severely traumatized lower limb as they affect likely limb prognosis. Open wounds are assessed with an estimation of tissue loss and contamination, with the application of sterile dressings and administration of antibiotic and tetanus prophylaxis. Obvious lower limb deformity can be corrected under adequate analgesia, prior to appropriate radiographs being obtained and splints or plaster being applied to ease patient discomfort.

There has been much recent debate with regard to the merits of limb salvage versus amputation. The MESS is one tool available to help assess the need for amputation. The measured parameters include: patient age, haemodynamic status, tissue ischaemic time, and the degree of soft tissue injury and contamination. Such scoring systems cannot substitute for sound clinical judgement, experience, and a team approach.

The main principles in the treatment of lower limb injuries are: adequate reduction and stabilization of long bone fractures; reduction and restoration of joint surfaces; and the maintenance of a viable soft tissue envelope. Reamed intramedullary stabilization of closed and open femoral and tibial diaphyseal fractures in the polytraumatized is standard with the main indications for external fixation being: severe soft tissue injury; poor patient physiological status; skeletally immature bone; and a narrow intramedullary canal. Intramedullary fixation is preferred for all other types of open fracture. Unreamed intramedullary nailing theoretically reduces the pulmonary fat embolic release from the fracture site. However, the stimulation of the periosteal blood supply and generation of autogenic bone grafting produced by reaming are thought to be reasons for the higher rates of non-union and implant failure associated with unreamed intramedullary fixation of both open and closed fractures.

The use of a radiolucent table can reduce operative time in the polytraumatized patient. It allows easier access to multiple injuries. Antegrade nailing is predominantly performed, with the main indications for retrograde femoral nailing being: the obese patient; distal femoral fractures; ipsilateral femoral and tibial shaft fractures (i.e. the ‘floating knee’); ipsilateral femoral neck and shaft fractures; and the pregnant patient.

The joint disruption and associated soft tissue swelling that can accompany pilon or tibial plateau fractures can be initially treated with a spanning external fixator. This stabilizes the injury, restores limb length, and allows the soft tissues to recover, whilst ligamentaxis aids articular surface reduction. Definitive internal fixation using minimally invasive incisions can then be performed initially if the soft tissues and patient’s physiological status allow. However, a staged procedure with initial external fixation and definitive stabilization performed 1–2 weeks after injury is a reasonable alternative with low risks of infection and complications. Displaced intracapsular hip fractures, hip dislocations, and acetabular fractures with radiological evidence of incarcerated bone fragments are the more common examples of proximal lower limb injuries that require urgent surgical intervention in order to reduce the incidence of bone necrosis and articular cartilage damage.

Direct pulmonary injury can occur due to aspiration, pneumonia, pulmonary contusion, and toxic inhalation. Indirect end-organ damage can also occur as a result of sepsis, multiple transfusions, over-aggressive fluid management, and disseminated intravascular coagulation. Severe chest injury is relevant to orthopaedic trauma patients as there is much debate regarding the optimal method of long-bone fracture fixation in order to minimize secondary pulmonary damage. A higher Injury Severity Score (ISS) increases the likelihood of developing systemic complications after injury. This has been confirmed in a retrospective review of 1278 trauma patients. A correlation was established between: ISS, the systemic inflammatory response to trauma (SIRS), and the incidence of acute respiratory distress and multiple organ dysfunctions.

The screening of trauma patients to identify those ‘at risk’ of developing respiratory insufficiency and symptoms related to fat embolus is key to the early diagnosis and treatment of the condition. Following long-bone injury, males under the age of 30 years with significant and early hypoxaemia are considered to be at a higher risk of developing respiratory insufficiency. Age may be a key factor in the development of symptoms related to fat embolus. In a consecutive series of 274 patients with isolated femoral shaft fractures, a 4% incidence of fat embolism syndrome (FES) occurred. There were no cases in patients aged over 35 years. The risk of developing FES was also reduced by early intramedullary fracture stabilization within 10h of admission. All 11 cases of FES in this study occurred in patients aged under the age of 35 years who had delayed (>10h) femoral fracture stabilization. Elderly patients are also more susceptible to the systemic effects of trauma with a lower (50%) lethal ISS required in patients aged over 65 years. Prolonged bed-rest and poor mobility are associated with increased morbidity and mortality in this age group.

Predictors for respiratory distress in adults include youth, high ISS, the presence of a femoral fracture, the combination of abdominal and extremity injuries, and physiological compromise on admission.

Peripheral limb injuries that involve long-bone diaphyseal fractures constitute a leading cause of hospitalization related to non-fatal injury. The initial treatment of these injuries was often delayed in order to ‘optimize’ a patient’s condition. Immediate surgical treatment to stabilize these injuries was thought to worsen prognosis owing to further tissue damage and haemorrhage. However, it became apparent that early skeletal stabilization actually reduced the incidence of complications and improved outcome. Early intramedullary long-bone fracture stabilization reduces mortality rate in seriously injured patients, with reduced respiratory complications, reduced mortality and length of stay.

A policy of early long-bone fracture stabilization has been recommended to improve and reduce the frequency of respiratory and systemic complications after injury. The term ‘early total care’ has been applied to the definitive and early (<24h from injury) reamed intramedullary fixation of long-bone fractures and is considered the optimal form of treatment and a surgical priority in the seriously injured.

However, concerns have been raised with regard to secondary pulmonary and systemic embolic events, possibly linked to reamed intramedullary surgical techniques in the seriously injured. Patients with a low injury severity benefited from early long-bone stabilization with fewer respiratory complications. However, this benefit was not seen in patients with an ISS of greater than 18.

The concerns regarding the physiological effects of early reamed intramedullary femoral stabilization have been extensively investigated by the Hanover group, and they concluded early reamed nailing in high ISS patients increased the risk of ARDS and multiple organ failure.

Conservative surgical techniques that reduce operative time and tissue insult were proposed in seriously injured patients to minimize the ‘second hit’ caused by surgery. The term ‘damage control’ was applied to these surgical techniques. The types of patients thought to benefit from ‘damage control’ were those who had sustained serious penetrating or blunt injury with persistent hypothermia, coagulopathy, and acidaemia despite resuscitation. In such patients, the risk of metabolic failure from surgery was considered greater than the risk of failing to complete the initial definitive procedure. The broad principles of ‘damage control’ surgery include: limited procedures to control haemorrhage and stabilize life-threatening injuries; physiological patient monitoring within an intensive care environment; definitive surgery once the patient’s condition has been optimized.

The anatomical areas where damage control surgery could be applied have expanded and now include trauma patients with pelvic and peripheral limb injuries. These alternative surgical strategies involve the use of temporary external femoral fracture fixation to minimize the ‘second hit’ of surgery in the physiologically vulnerable patient. Delayed conversion to definitive reamed intramedullary fixation is performed once the patient’s condition has been optimized.

The use of external fixation is more common after pelvic fractures to reduce pelvic volume and limit blood loss. Initial external fixation is, however, a viable alternative to intramedullary stabilization of long-bone fractures. External fixation can provide adequate temporary stabilization in severely injured patients with a rapid operating time, reduced blood loss, and reduced pulmonary embolic load being potential benefits. Successful delayed conversion to definitive intramedullary fixation can be performed at an average of 5 days following initial treatment, but is reserved for the more seriously injured patients with a mean ISS of 29. This often includes associated injuries to the head, chest, and abdomen. Conversion to intramedullary fixation is performed at an average of 7 days after initial surgery with low infection rates (1.7%).

Advocates of this surgical strategy would indicate that following injury, the degree of initial trauma and the patient’s subsequent biological response cannot be altered. Outcome can only be improved by minimizing the ‘second hit’ of surgery. Advocates of ‘early total care’ would argue that the degree of initial injury alone is the sole contributing factor to the development of subsequent systemic complications and that the method of fracture fixation is inconsequential given a background of severe injury.

There is agreement about certain principles;

There is no general agreement about which patients are suitable for ‘damage control orthopaedics’ (DCO) but it should be considered in multiple trauma patients with a significant chest injury or an ISS probably in excess of 30. Other patients can be treated by standard methods of long-bone fixation. Adequate haemodynamic and metabolic resuscitation are paramount prior to surgery. Uncorrected metabolic acidosis in the seriously injured appears to be a key feature with increased pulmonary and systemic complications after fracture fixation surgery. The clinical indicators used by the Hanover group, where DCO techniques have been most widely reported are: ISS higher than 20 with an associated chest injury; polytrauma with abdominal/pelvic trauma and shock (systolic blood pressure <90mmHg); ISS higher than 40 with no chest injury; x-ray evidence of bilateral lung contusions; mean pulmonary arterial pressure greater than 24mmHg; increase of more than 6mmHg in pulmonary arterial pressure after intramedullary reaming.

They have also described certain clinical parameters associated with a poor outcome after serious injury. These include: inadequate resuscitation, coagulopathy, hypothermia, multiple blood transfusions (>25 units), multiple long-bone fractures, excessive surgical time (>6h), metabolic acidosis (pH <7.24), and an exaggerated inflammatory response judged to be an IL-6 measurement of >800pg/mL.

Damage control techniques have also been extended to include aspects of initial patient resuscitation. Aggressive fluid therapy has the potential to exacerbate lung interstitial oedema. Therefore, the concept of delayed fluid therapy may form part of a ‘damage control’ surgical protocol in order to avoid this complication. Invasive monitoring of central venous, arterial, and pulmonary arterial pressures allows a more accurate assessment of hypoxaemia and true haemodynamic status. The effects of surgery and other therapeutic interventions can then be closely monitored with regular blood sampling allowing oxygen, carbon dioxide, and lactate levels to be closely monitored.

Ventilatory strategies in polytraumatized patients have also altered. Conventional therapy is aimed to maximize oxygen delivery and obtain normal arterial blood gas measurements. This often involved the use of high tidal volumes and pressure ventilation techniques. These may have the potential to cause secondary pulmonary damage and could predispose to the development of acute respiratory distress after injury. Lung protective protocols are now often implemented in the seriously injured which involve less aggressive ventilatory intervention. The goals are to facilitate pulmonary recovery and to prevent any further alveolar damage. Low tidal volumes are used with pressure limited ventilatory techniques and non-toxic concentrations of inspired oxygen to achieve ‘adequate’ arterial blood gas concentrations.

With regards to surgery the ‘DCO’ concept can be extended out with the most recent debates with regard to femoral fracture fixation. A pelvic ring injury, where haemorrhage is poorly controlled and exsanguination imminent, can also be suitable for DCO. The role of angiography and arterial embolization has been debated. The time taken to perform this procedure has been shown to correlate with mortality rate. In order to avoid delay some trauma centres advocate minimally invasive pelvic fixation (with a pelvic binder or external fixator) followed by pelvic packing if this does not obtain haemodynamic control. Any haemodynamic, metabolic, or coagulative problems can then be corrected in an intensive care environment and definitive pelvic surgery arranged as a secondary procedure, once the patient’s condition has been optimized.

There have also been concerns about intramedullary fracture fixation in the multiply injured patient with a head injury, but these have not been confirmed. Early fracture stabilization has the potential to reduce pain and minimize further soft tissue damage and fat embolism release, and should form part of the initial management of patients with a head injury along with adequate resuscitation. Improved neurological outcome does appear to be related to intracranial pressure monitoring and aggressive management if required. Optimal outcomes have been demonstrated by maintaining a cerebral perfusion pressure of above 70mmHg with intracranial pressures of below 20mmHg.