Early total care to early appropriate care - What every anesthesiologist must know!

Abstract

Orthopedic trauma is one of the commonest injuries necessitating surgical intervention in a trauma patient. The management protocols in such severely injured orthopedic patients have evolved from conservative treatment to ‘early total care’ (ETC) to ‘damage control orthopedics’ (DCO) and recently to ‘early appropriate care’ (EAC)/‘safe definitive surgery’ (SDS). ‘DCO’ involves emergent, basic minimum life- or limb-saving surgery with continued resuscitation and definitive fixation of fractures being done later, once the patient has been resuscitated and stabilized. An insight into the immunological processes at a molecular level evoked in a poly-traumatized patient led to the evolution of the ‘two-hit theory;’ ‘first hit’ being the injury itself while the ‘second hit’ caused by the surgical trauma. As the ‘two-hit theory’ gained popularity, it led to a delay of definitive surgery for 2–5 days following trauma, since a higher complication rate was observed following definitive surgery within the first 5 days of the injury. This is a review article on the historical perspectives of DCO, immunological mechanisms involved, and various injuries requiring damage control approach or EAC/ETC and their anesthetic management.

Introduction

Musculoskeletal injuries are frequently associated with blunt trauma. Injuries like pelvic fractures, long-bone fractures, severe crush injuries, fractures associated with vascular compromise, and traumatic amputation can all lead to hemorrhagic shock and require emergent resuscitation. An anesthesiologist is usually involved in the resuscitative efforts of such severely injured patients who present to the emergency department with hemorrhagic shock. The anesthesiologist not only provides anesthetic services in the operation room (OR) and radiology department but also actively participates in the decision-making process, in consultation with the trauma surgeons, toward early total care (ETC) versus damage control orthopedics (DCO). The anesthesiologist is also in an ideal position to assess the physiology of the patient and advice regarding the ideal timing for definitive surgery.

ETC versus Damage Control

The management protocols for poly-traumatized patients with significant musculoskeletal injuries have evolved over the past few decades into two basic schools of thought—ETC versus the DCO. The anesthesiologist involved in the care of trauma victims should be familiar with both the strategies.

ETC

Prior to the 1950s, a poly-traumatized patient with significant musculoskeletal injuries was considered physiologically too sick to undergo major orthopedic surgical interventions to stabilize the fractures.^[1,2] Pioneering studies in the 1970s challenged this concept and demonstrated that early surgical fixation of long-bone fractures, in fact, was beneficial and reduced the pulmonary complications and post-operative morbidly in poly-traumatized patients.^[3,4] It was the landmark study by Bone et al.^[5] in 1989 which firmly established that early fixation of all long-bone fractures (within 24 h), reduced the pulmonary complications, length of intensive care unit (ICU) stay as well as the hospital stay in poly-traumatized patients. Early definitive fixation of fractures enabled early mobilization and rehabilitation of patients and prevented the complications inherent to prolonged immobilization. A paradigm shift from “too sick to operate” to “too sick not to operate” was seen as a result of these studies.^[3–5] The term ‘early total care’ came into vogue and referred to the early (24–48 h) definitive surgery for all long-bone fractures in a polytrauma patient. However, reports, contrary to the concept of ‘ETC,’ and challenging the philosophy of urgent major orthopedic fixations started emerging at the same time. These reports highlighted the unexpected rise in pulmonary complications and multiorgan dysfunction (MOD) observed in physiologically unstable patients, who had been treated with the ETC approach. These conflicting reports concluded that ETC could not be ubiquitously applied to all multiply injured patients, and thus, emerged the concept of ‘DCO.’^[6,7]

Damage control orthopedics

The concept of ‘damage control surgery’ was first used in the surgical management of abdominal trauma.^[8] The same concept was extrapolated to the management of patients with severe musculoskeletal injuries, and hence, evolved the term ‘damage control orthopedics’ or ‘DCO.’ This concept was first practiced by trauma surgeons in Germany, who observed that multiply injured orthopedic trauma patients with femoral shaft fractures had better survival rate when femur fractures were stabilized with external fixator as a temporizing measure in the acute phase.^[9]

The DCO approach consists of three stages.^[4] The first stage involves only the life-saving procedures during the acute phase. The temporizing external fixation of the major skeletal fractures, hemorrhage control, and management of soft tissue injuries is performed during this stage. The second stage focuses on the resuscitation of the patient in ICU with monitoring and optimization of patient physiology. The third and final stage entails definitive fracture fixation in a stable and optimized patient [Figure 1]. The orthopedic interventions encompassed within the ambit of DCO include external fixation of fractures and splintage or sling application. Upper extremity fractures can generally be stabilized with splintage or external fixators. Lower extremity and pelvic fractures are better stabilized with external fixators.

Figure 1: Damage control orthopedics: Staged management of hemodynamically unstable polytraumatized patient

First hit and second hit concept

Conceptual evolution into the pathophysiology and immunological host response to injury led to the proposition of the “two-hit theory.” This led to a paradigm shift in poly-trauma management from ETC to DCO.^[10] Poly-trauma and shock incite an inflammatory response in the body. This inflammatory response may be generalized and uncontrolled in cases of massive injuries resulting in systemic inflammatory response syndrome (SIRS) and generalized tissue damage predisposing the patient to MOD and early death. The body mounts a counter-regulatory anti-inflammatory response (CARS) to balance SIRS via cellular mediators resulting in immunosuppression.^[11] The initial trauma which induces the inflammatory response is termed the ‘first hit’^[12] [Figure 2]. Obertackle et al.^[13] emphasized the importance of ‘first hit’ when they demonstrated increased permeability in pulmonary microvasculature using bronchopulmonary lavage in poly-trauma patients. The authors demonstrated a high correlation between increased pulmonary microvascular permeability within 6 h following trauma and subsequent development of acute respiratory distress syndrome (ARDS). A second insult in the form of a major surgical intervention during this phase represents a ‘second hit’ and may tilt the balance toward MOD and multi-organ system failure (MOSF). The physiological responses following ‘first hit’ of major trauma and ‘second hit’ of a major surgical procedure stress and deplete the patient’s biological reserves, and thus play a decisive role in determining the timing for definitive surgical fixation [Figure 2].^[14]

Figure 2: Representing two-hit theory in a severely injured patient. First hit is the initial injury and the second hit is the definitive orthopedic procedure, e.g., pelvic internal fixation and femoral nailing Abbreviation: MODS: Multiple organ dysfunction syndrome, ARDS: Adult respiratory distress syndrome

Injury severity markers

Many inflammatory markers have been studied to predict patients at the risk of developing SIRS and MOD.^[14,15] At present, only two markers, interleukin (IL)-6 and human leukocyte antigen (HLA) DR-Class II molecules seem promising and have shown clinical utility in predicting patient outcome and prognosis. IL-6 has demonstrated a good correlation with severity of injury, inflammatory response, and clinical outcome and has now become a part of routine laboratory investigation in large trauma centers.^[16,17]

Patient selection for damage control

The decision to manage a poly-trauma patient with ETC or DCO is primarily clinical. Although biomarkers like IL-6 or genetic testing may aid in predicting outcomes but performing these tests in routine practice is neither practical nor feasible. Four clinically significant factors suggested by Pape et al.^[18] to decide the patient management protocol between ETC versus DCO were acidosis, coagulation profile, temperature, and soft tissue injuries. Pape classified the patients into four groups based on these parameters: patients in extremis, unstable patients, borderline patients, and stable patients. These clinical grading criteria were further modified by Nahm et al.^[19] and validated in a retrospective analysis of 1,196 trauma patients. The suggested clinical grading system with modifications by Nahm et al. along with the base deficit range in various classes of shock in the updated Advanced Trauma Life Support (ATLS) is given in Table 1.^[20] Stable patients are ideally suited for ETC, while ‘patients in extremis’ and ‘unstable patients’ are better managed with DCO approach. A major surgical intervention represents a ‘second hit’ in these patients and may lead to serious complications like ARDS, multi-organ failure, or even death. The ideal treatment protocol for borderline patients remains debatable and inconclusive. Borderline patients appear ‘stable’ prior to surgery but deteriorate suddenly in the post-operative period with the development of organ dysfunction. It is prudent to treat these patients with DCO if any prognostic factor is not fulfilled. The criteria to describe a borderline patient are given in Table 2. The clinical parameters which favor a DCO approach over ETC in borderline patients include acidosis (PH <7.24, serum lactate >2.5 mmol/L), hypothermia (temperature <35° C), coagulopathy (platelets <90,000/ccm), expected surgical time >90 min and transfusion >10 units of packed red blood cells.^[21,22]

Table 1: Range of clinical parameters defining the clinical grades, i.e., stable, borderline, unstable, and extremis

Table 2: Criteria for describing a “borderline patient”

Major orthopedic trauma like pelvic fractures, femoral fractures with poly-trauma, and multiple injuries in a geriatric age group are also better managed using DCO protocols. The surgical priorities and application of damage control approach in multiply injured patients are depicted in Figure 3.

Figure 3: Flowchart depicting the prioritization of surgery in a polytraumatized patient and the appropriate application of damage control concept. Damage control approach may be necessitated in a borderline patient at any point of time. Abbreviation: ABG: Arterial blood gas, OR: Operating room, ICU, Intensive care unit, ETC: Early total care, DCO: Damage control orthopedics

Early appropriate care (EAC)/safe definitive surgery (SDS)

As the care of trauma patients has improved and the fluid resuscitative strategies and monitoring have refined, a new approach of tailoring the surgical fracture management has emerged and is referred to as “EAC” or “SDS” thus offering the benefits of ETC and safety of DCO.^[23] The basis of this approach is that the response to damage control resuscitation is dramatic in a majority of the patients thus giving an opportunity for early (within 24–36 h of admission) surgical fracture fixation.^[24] Valier et al.^[25] conducted a retrospective study of 1,442 patients with femoral shaft, pelvic and spinal fractures with the aim to determine the optimal timing of surgery. The authors concluded that unstable fractures of the axial skeleton and long bones must undergo definitive surgery within 36 h of injury provided there is a demonstrable response to resuscitative efforts, i.e. reversal of acidosis: serum lactate <4 mmol/L, pH ≥7.25 or base excess more than 5.5 mmol/L.

EAC/SDS is best suited for borderline patients, however, this is a team decision which needs to be taken on a case-to-case basis. In case of any deterioration intraoperatively during EAC, a proactive decision to abandon the definitive procedure must be taken by the team and safer options must be chosen.

Injuries Requiring Damage Control Approach

Pelvic ring injuries

Major pelvic ring disruption is best managed using the DCO approach. Pelvic fractures lead to hemorrhagic shock and mortality in 5–30% of the patients with a pelvic injury, which may be as high as 50% in patients with open pelvic fractures.^[20] ‘Open book’ type pelvic fractures (anteroposterior compression injuries) are commonly associated with hemorrhagic shock. The pelvic volume increases significantly in ‘open book’ type injuries and may hold up to 4–5 L of blood leading to exsanguination and shock. Lateral compression injuries, on the other hand, do not cause such severe shock as the pelvic volume is not significantly increased in these injuries. Vertical shear pelvic fractures are highly unstable with disruption of extremely strong sacroiliac, sacrospinous, and sacrotuberous ligaments and may lead to significant blood loss and shock.

Management

The goal of the treatment in major pelvic injuries is to control hemorrhage with concomitant volume resuscitation. All interventions are directed at reducing the pelvic volume thus creating a ‘tamponade’ effect with a reduction in venous bleeding. Application of a commercially available pelvic binder or wrapping a sheet around the pelvis is a quick and simple technique to stabilize the pelvis. Open book injuries can be quickly stabilized with anterior external fixators (anterior pelvic ring stabilization). Posterior pelvic ring injuries and vertical shear fractures are stabilized with ‘C’ clamp, with or without longitudinal skeletal fraction (posterior pelvic ring stabilization). Application of pelvic binder, external fixator or C clamp are the key components of pelvic injury management using the DCO approach.^[26,27]

Patients not responding to external stabilization measures (pelvic binder, fixators, C clamp) may have an arterial source of hemorrhage which may be present in around 10–15% of the patients with pelvic fracture bleeding.^[28] Contrast extravasation on computed tomography (CT) angiography is an accurate indicator for the diagnosis of arterial bleed.^[29] Furthermore, the exact site of arterial bleed can be localized, thus facilitating timely angiographic embolization of the disrupted vessel. Occasionally, the patient may require further operative intervention in OR after angioembolization. Seamless transition from radiologic suite to OR should be ensured by the anesthesiologist. In case the patient is in extremis and cannot be transported to the angiographic suite safely, internal pelvic packing (open laparotomy) is performed.

Anesthetic management of pelvic fractures with hemodynamic instability

Emergency operative procedures like the application of external pelvic fixator and debridement, damage control laparotomy, or interventional radiologic procedures like angioembolization may require anesthetic services. The unstable patient would require angioembolization of disrupted vessels in the angiography suite and then be transported to OR. The same standards of anesthesia care should be maintained in the radiology suite as those used in the OR.

Control of major hemorrhage may require immediate abbreviated life-saving surgery. Shifting the patient from the transport trolley to the OR table should be done cautiously to ensure minimal pelvic movement and avoid further bleeding. All patients, unless proven otherwise, should be suspected to have a cervical spine injury and manual inline stabilization (MILS) should be maintained while shifting the patient and performing airway interventions. No attempt should be made by the anesthesiologist to remove the pelvic binder for cannulating the femoral vein or artery. One should have a low threshold for central venous catheter insertion to guide fluid resuscitation and placement of arterial line, as non-invasive blood pressure monitoring may be unreliable in a shock state. Invasive blood pressure monitoring would assist in guiding resuscitation and also provide easy access for repeated blood gas monitoring and serum lactate levels.

All efforts for control of bleeding should be made with simultaneous fluid resuscitation. However, fluid overload should be avoided as a component of damage control resuscitation as overzealous fluid administration results in an increased compartment (abdominal, extremity) pressure, dilutional coagulopathy, electrolyte disturbance, anemia, thrombocytopenia, and an increased incidence of ARDS. Cold fluids can lead to or exacerbate pre-existing hypothermia, worsen the acidosis, and thus increase the overall mortality. Thus, ongoing blood loss should be replaced with blood and blood products rather than crystalloids or non-blood products containing colloids.^[30] Massive transfusion protocols should be activated to ensure the administration of a prefixed proportion of blood and blood products. Cell salvage system should be used in these patients with massive life-threatening blood loss.^[31] Tranexamic acid should be used in patients with serious hemorrhage within 3 h of trauma to decrease bleeding.^[32] Hypotensive resuscitation should be practiced to avoid re-bleeding and systemic blood pressure should be maintained at 80–90 mmHg unless there is associated traumatic brain injury (TBI).^[33] Unstable patients with pelvic ring injuries undergoing DCO would be further managed in ICU. Extubation of the trachea can be planned once the patient stabilizes.

Long-bone fractures with traumatic brain injury

Patients with TBI and concomitant long-bone fractures are also suitable candidates for management using DCO principles. TBI leads to an increase in intracranial pressure (ICP) and consequently compromises cerebral perfusion pressure (CPP). Any reduction in the mean arterial pressure (MAP) can further decrease CPP and endanger cerebral perfusion. Compromised cerebral perfusion may lead to cerebral ischemia and brain edema thus increasing the ICP further and setting up a vicious cycle. Definitive fixation of long-bone fractures at this stage can cause significant blood loss and induce systemic hypotension. Intramedullary nailing of long-bone fracture may also cause concomitant hypoxia. Both hypoxia and hypotension are detrimental for TBI and result in secondary brain injury. In spite of the large number of studies published in its favor, the DCO approach remains controversial in this group of patients.^[34,35] It is reasonable to assume that although DCO is a safe initial approach, treatment should be individualized for each patient.

Anesthetic considerations

General anesthesia (GA) is a preferred anesthetic technique in patients with femoral fractures with associated TBI. Titrated doses of anesthetic/sedative drugs must be administered, thus maintaining hemodynamic stability. All efforts should be made to maintain CPP >70 mmHg by maintaining systemic arterial pressure. If ICP monitoring is being done, it should be maintained <20 mmHg. Hypoxia and hypercapnia should be avoided to prevent secondary brain injury. Hypotensive resuscitation, which is otherwise recommended in trauma resuscitation, is contraindicated in this group of patients.

Long bone fractures with chest trauma

There continues to be a clinical dilemma in the management of polytrauma patients with concomitant long bone fractures and chest trauma. Some authors propagate that early definitive fixation of long bone fractures is safe,^[36] while others contend that definitive surgery for long bone fracture fixation within 48 h may actually be harmful.^[37] Although there is not enough evidence in favor of delayed definitive fixation, some studies have demonstrated a higher incidence of ARDS following early (<48 h) definitive fixation for long bone fractures with concomitant chest trauma.^[37,38] In the absence of conclusive literature on the timing of definitive surgery for long bone fractures, it is prudent to individualize treatment on a case-to-case basis.

The clinical parameters which may help in the decision-making process include^[39]

1. Severity of pulmonary dysfunction (PaO2/FiO2), lung compliance, and positive end-expiratory pressure (PEEP) requirement
2. Hemodynamic status
3. Expected/surgical time
4. Expected blood loss
5. Severity of fracture (open or closed)

Anesthetic management

Anesthetic considerations in these patients are similar to the other trauma patients. In case the patient is hemodynamically stable with a normal coagulation profile, regional anesthesia (RA) may be instituted. Adequate resuscitation prior to spinal anesthesia is essential to avoid sudden hypotension, since a significant amount of blood at the fracture site may have been lost in these patients. Lung protective mechanical ventilation strategies should be employed to prevent the exacerbation of lung injury. Nitrous oxide should be avoided to prevent the exacerbation of occult pneumothorax.

Bilateral femoral fractures

Bilateral femoral shaft fractures also have an equivocal prognosis and a myriad of treatment options. This injury pattern is associated with a high complication rate and mortality. Though not amply supported by literature, it is safe to treat bilateral femoral shaft fractures with the DCO approach.

Soft tissue injury

Significant soft tissue injury is also an indication for adopting the DCO management approach. Early internal fixation in fractures with massive open wounds or extensive soft tissue injuries is associated with high rates of infection and poor outcome.^[40] These fractures are ideally treated using DCO principles. A thorough debridement with external fixation to stabilize the fracture, use of antibiotic-impregnated beads, and vacuum-assisted closure dressings to address the wounds have become a standard protocol in the management of open orthopedic injuries and compound fractures. Once the wounds have healed satisfactorily and there is no evidence of an infection, definitive fracture fixation can be done.

Change of vac dressing can be done under sedation at the bedside, while debridement and deep wound dressing would require RA/GA. Repeated anesthesia may be required in these patients. An epidural catheter can be used for both analgesia and anesthesia.

When to Convert Temporary Fixation to Definitive Fixation

The ‘golden period’ for definitive fracture fixations in patients managed with the DCO approach is between 5 and 14 days, in a majority of the cases. However, a delay of more than 2 weeks is inadvisable due to increased fixator pin site infections observed in patients in whom definitive surgery is delayed for more than 15 days.^[41] The entire trauma team must take proactive decisions for EAC/SDS as soon as the physiological parameters are normalizing to prevent the complications of delayed surgery. However, this decision needs to be taken on a case-to-case basis.

For patients with open fractures, crush injuries, and significant wounds, the condition of soft tissues dictates the ideal time for definitive fracture fixation. A majority of such injuries can be definitively treated within a window of 10–21 days when the condition of the soft tissues is optimal.

Summary

The concept of DCO is ideally suited for the management of hemodynamically unstable patients with pelvic fractures, long bone fractures with TBI, long bone fracttures with chest trauma, open fractures with significant soft tissue injury, and patients in extremis. The goals of anesthetic management are maintenance of oxygenation, and ventilation with prevention of lethal triad of hypothermia, acidosis, and coagulopathy. In hemodynamically stable patients, ETC is the optimal treatment. Repeated assessments must be done to take proactive decisions on EAC to expedite the definitive surgery and minimize complications. A proactive anesthesiologist working in concert with orthopedic and trauma surgeons plays a pivotal role in saving lives and limbs.

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Conflicts of interest

There are no conflicts of interest.