Monitoring Intracranial pressure A pressure transducer inserted into the non-dominant cere- bral hemisphere (intraparenchymal) is the most commonly used site in the UK. This gives a continuous, reliable and Post-trauma, cell injury mechanisms These include excitotoxicity, in \202 ammation, pyrexi a, hyper- glycaemia, apoptosis and free radical damage. 485 CHAPTER 28.2 Head injury rapidly responsive estimation of ICP. Intraventricular cathe- ters are the gold standard an d they allow sampling of CSF. However, they are associated with an increased risk of infect ion, particularly when used for periods >7 days. Hypertonic solutions Providing the patient is normocapnic and adequately sedated, hypertoni c solutions are the \201 rst-line agents used to treat persistently elevated ICP. Promisi ng level 3 evi- dence is emerging on the use of hypertonic saline, and this may provide a u seful treatment in the future. Boluses of 2ml/kg of a 20% mannitol solution provide rapid a nd effective reduction in ICP. Metabolic monitoring Focal tissue oxygenation (PBRO2) Continuous measurement of tissue oxyg enation is available and in current use in some departments in the UK. PBrO2 gives an early warning of impending ischaemia and may allow for less vigorous treatment of ICP. It also c an guide alternative therapies to improve oxygen delivery, such as red cell transfusion and inotropes. A limitation is that oxygenation in a single area of brain tissue may not re \202 ect other areas of the brain, and that \200\230tissue ischaemia \200\231 may be due t o mitochondrial failure. There is some evidence that directing treatment to PBrO2 improves outcome in com- parison with ICP-directed treatment. Jugular bulb oxygen saturation (SjvO2) SjvO2 is a global measure of brain oxygenation; however, it suffers from the same limitati ons as PBrO2 in that areas of the brain that are not extracting oxygen will falsely elevate readings. Metabolic suppression Suppression of cerebral electrical activity produces signi \201 - ca nt reductions in ICP in patients who have intact coupling between cerebral metabolism and \202 ow. This can be tested by PaCO2 responsiveness or a test dose of hypnotic agent. In r esistant raised ICP, barbiturates are recommended. These are administered as boluses follow ed by an infusion, with continuous monitoring of brain electrical activity to achieve burst suppression. Surgical intervention Early surgical intervention saves lives after head injury. Indication s include hydrocephalus, contusions, extradural and subdural haematomas. In addition, the r ole of decompressive craniectomy is currently under investigation, with some promising pilo t studies. Cerebral blood \202 ow PET scanning, perfusion CT scans and perfusion-weighted MRI techni ques have all been used to estimate CBF. These techniques are not continuous, are technical ly dif \201 cult and are unable to predict what level of perfusion is required to match me tabolic demands for individual areas of the brain. They are, however, useful as research to ols. Cerebral protection Hypothermia Pyrexia is common in brain injury and is associated with a worsening of outcome. It may be centrally mediated and independent of an infective cause. H ypothermia has been shown to be effective in animal models; however, trials of therapeutic hypothermia have failed to show bene \201 t. Hypothermia is associated with an increase in need for support of the circulation, electrolyte abnormalities, a raised serum amylase, bl eeding and arrhythmias. Maintenance of normothermia is common practice either by active coo ling or by pharmacological intervention. The lack of evidence surrounding pharmacological n euro- protective intervention makes it unlikely that changes in care for patients with seve re head injury in hospitals without neurological services would deliver outcome improvement s of the magnitude that could follow signi \201 - cant expansion in neurological intensive care facilities. Microdialysis Future monitors may include microdialysis of glucose, pyruvate and lactate, i ndicating areas of brain with inade- quate perfusion. Measurement of excitotoxic amines and in \202 ammatory mediators may also be useful in the future; but this is still at the exp erimental stage. General ICU care The focus of care is the avoidance of medical complications and the provis ion of an environment optimal for brain recovery. The Brain Trauma Foundation (BTF) recomme nds; \200 Keep sodium >140mmol/l. A decrease in serum sodium produces an osmotic gradient across the blood \200\223 brain barrier and aggravates cerebral oedema. Avoid hyperglycaem ia (treat blood glucose >11mmol/l). Hyperglycaemia may aggravate ischaemic brain injury by increasing cerebral lactic acidosis. Feed via orogastric tube and use motility agents as re quired Use TED stockings and avoid low dose heparin Apply 15 \200\22330 head-up tilt with head in neutral position No parenteral, non-ionic \202 uid to be given. Conclusion It therefore remains the priority of neurointensive care to deliver the assured physiological parameters and prevent medical and surgical complications impairing the patie nt \200\231s recovery. \200 Further reading http://www2.braintrauma.org/site/Pageserver? pagename=guidelines Speci \201 c treatment of raised ICP Hyperventilation Prolonged hyperventilation is detrim ental; however, there is controversy whether short-term hyperventilation in response to an acute rise in ICP is harmful. It is ef \201 cacious in reducing ICP; but there is doubt as to how quickly after hyperventilation CBF returns to normal, which may be up to 24h. The B TF guidelines recommend that hyperventila- tion is limited to short periods and only when r esponse to other medical treatments for raised ICP have failed. Recommended target PaCO2 is between 4 and 4.5kPa. Marshall LF. Epidemiology and cost of central nervous system injury. Clin Neurosurg 2000; 46: 105 \200\22312. Ravussin P. Abou-Madi M, Archer D, et al. Changes in CSF pressure after mannitol in patient s with and without elevated CSF pressure. J Neurosurg 1988; 69: 869 \200\22376. Stieffel MF, Spiotta A, Gracias V, et al. Reduced mortality rate in patients with severe tr aumatic brain injury treated with brain tis- sue oxygen monitoring. J Neurosurg 2005; 103: 805 \200\22311. Sahuquillo J, Arikan F. Decompressive craniectomy for the treat- ment of refractory high in tracranial pressure in traumatic brain injury. Cochrane Database Syst Rev 2006; (4): CD0039 83. 486 B WINTER, S SARKAR & H PATTANI Spinal trauma with marked physiological sequelae, which are dependent on the level and extent of injury. Acutely there is a \202 accid paralysis below the spinal level, which after resolution of the spinal shock phase develops into spasticity. Respiratory failure is more common in com plete than incomplete SCI. Diaphragmatic supply is from C3 \200\2235, and injury above C3 r esults in apnoea. Injuries below C5 may have diaphragmatic function maintained. However, ma rked ventilatory dysfunction is apparent in the acute setting, with loss of intercostal mus cle function; diaphragmatic con- traction and descent occurs with chest wall indrawing rath er than expansion. FVC and maximal inspiratory force are reduced by nearly 70%. Similarly, loss of abdominal wall contraction reduces expiratory effort. These result in atel- ectasis , hypoventilation and hypoxaemia. Ventilator dependence correlates strongly with level of i njury; C1 \200\2234: 65 days, C5 \200\2238: 22 days, thoracic: 12 days. One-third of patien ts with cervical injuries will require intubation within the \201 rst 24h of injury. Spec i \201 c indications include: \200 fatigue \200 VC <1l \200 rising PaCO2 \200 risi ng respiratory rate Spinal injuries can lead to a poor quality of life, reduced func- tional independence and m arked \201 nancial and social implica- tions for ongoing care in survivors of major traum a. The severity of the sequelae of spinal cord injury has led to PHTLS and ATLS advocat ing the management of airway security with cervical spine control as a \201 rst priority. Cervical spine injury is associated with up to 10% of blunt polytrauma. Annually, there ar e 1000 new cases of cervical cord injury in the UK. The pattern of spinal injuries involves 55% in cervical, 15% thoracic, 15% at the thoracolumbar junction and 15% in the lumbosacra l area. With any injury involving the head, neck or upper torso, one should strongly suspec t a cervical spinal injury. Pre- existing spinal disease (rheumatoid arthritis/osteoarthrit is, ankylosing spondylitis, canal stenosis) increases the risk of potential spinal cord inj ury. Trauma patients are often obtunded and unable to give a complete history or be ade- qu ately examined neurologically in the resuscitation room. C spine clearance Initial management will involve the \200\230holy trinity \200\231 of sem i- rigid collar, blocks (sandbags) and tape. If the spine is pro- tected, then evaluation o f the spine can be withheld, whilst resuscitation and primary survey concentrate on ABCDE. In the polytrauma patient, this is often deferred to the ICU. The ICS has produced guidance on spinal evaluation in unconscious victims of blunt polytrauma (Fig. 28.3.1). The standar d 3-view cervical (craniocervical to C7/T1) radiograph series in the emergency setting may miss 5 \200\22310% of cervical injuries in the unconscious patient, and addi- tional helica l CT scanning of this region is recommended. Plain radiographs have a higher rate of detect ing ligamen- tous disruption and malalignment, but CT is better for detecting fractures. Ma ny trauma patients on the ICU will be sedated, venti- lated and have a potentially unstable C spine. Prolonged immobilization is associated with signi \201 cant morbidity, including airway and central venous access dif \201 culties, pneumonia, skin ulceration and venous thromboembolism. It is strongly recommended that the cervical thoracic and lumbar spine who remains unconscious be cleared within 48 \200\22372h. The routine use of MRI is not recomm ended, but should be urgently considered for any patient with a neurological de \201 cit w hich may be amenable to surgical intervention. Victims of polytrauma, high velocity injury or fall from a height of >6ft, who are obtunded and cannot be assessed clinically must have their thoracolumbar spine imaged. If thoracic/abdominal helical CT scanning is performed a s part of the assessment, then these can be reconstructed to assess the thoracolumbar spine . Ideally, scanning should be prior to admission to ICU to minimize the complications of tr ansferring critically ill patients within the hospital. After radiography, immobilization o f potential C spine injuries should be undertaken with a semi-rigid collar (e.g. Philadelph ia). Patients who are immobile (heavy sedation, paralyzed) may have sandbags and tape to mi nimize movement. It is better to be pre-emptive and undertake intubation in controlled circumstances, using manual in-line stabilization and a skilled anesthetist. Suxamethonium can be used up to 4 d ays after injury, with risks of severe hyperkalaemia thereafter. VAP is a signi \201 cant problem in this group of patients. In patients with injuries at C4 and below, the developme nt of chest wall spasticity enables a signi \201 cant number to be weaned from mechanical ventilation. Quadriplegics display better respiratory function when supine. This enables ab dominal contents to push the dia- phragm into a more favorable position for contraction. Tr acheostomy is often complicated by the site of cervical injury and potential surgical acces s for anterior approach stabilization. A delay of 2 weeks between surgery and tracheostomy has been suggested. Patients with C1 \200\2233 SCI who cannot be weaned are ventila- tor de pendent for life. These patients may be considered for home ventilation and/or phrenic nerv e electrostimulation. This is a signi \201 cant psychological and \201 nancial burden, a nd reiterates the need for careful spinal immobilization and handling during resuscitation and ongoing intensive care. Disruption of sympathetic out \202 ow and unopposed para- symp athetic action due to cervical SCI invariably leads to cardiovascular instability. Bradycar dias are common, though tachyarrhymias are also seen. These are most commonly seen in the \201 rst 2 weeks after injury. Tracheal suctioning can cause severe bradycardias or asysto le, which may be preventable with atropine. Adequate perfusion to the spinal cord must be e nsured to prevent secondary SCI. The loss of arteriolar tone in the peripheries leads to po oling and hypotension. Initially IV \202 uid can restore BP. With the disruption of cardi ac sympathetic accelerator out \202 ow in lesions above T1, car- diac output cannot be aug mented by heart rate and relies on stroke volume alone. Both vasopressors and chrono- trope s may be required to augment these respectively. Spinal cord injury (SCI) The aim of immobilization is to prevent further SCI or any deterio ration due to movement. SCI itself is associated 487 CHAPTER 28.3 Spinal trauma Evaluation for spinal injuries among victims of blunt polytrauma GROUP 1 PATIENTS Defined as those patients who fulfill all the 4 clinical pre-conditions be low 1) Glasgow Coma Scale (GCS) score 15 and appropriate responses 2) Absence of intoxicant s, alcohol or sedation/opioid analgesics 3) No midline spinal tenderness, no deformity or s teps and no neurological deficit referable to a spinal injury (e.g. abnormal tone, power or reflexes) 4) No significant distracting injury e.g. extremity fracture GROUP 2 PATIENTS Defined as patients who do NOT meet the 4 clinical preconditions are not u nder the care of ICU or intubated GROUP 3 PATIENTS Defined as patients who do NOT meet the 4 clinical pre-conditions above and are under the care of ICU and/or intubated e.g. traumat ic brain injury Blunt trauma victim arrives with a cervical collar, sandbags and tape in place. Clinical ev aluation by senior staff on the 4 clinical pre-conditions above: Group 2 Group 3 Group 1 GROUP 3 Do not meet all 4 clincial pre-conditions and are under the care of ICU or intubate d. Maintain mmob- ilisation and perform entire spinal evaluation ie 1) 2) Group 2 Do not meet all 4 clinical pre-conditions and are not under the care of ICU or intu bated. Maintain immobilization and perform 1) Lateral, AP and odontoid cervical Group 1 Satisfy all 4 clinical pre- conditions. Spine may be regarded as stable and uninjur ed. Close observation during mobilization is essential* Lateral and AP cervical radiographs. Multiplane helical (spiral) CT of the entire cervical spine down to and including the T4/T5 disk space. OR (if no helical CT available) \200\223 scanning of the cranio-cervical junction and the cervico thoracic junction (if not seen on plain radiographs and any suspicious areas of the c-spine Thoracolumbar AP and (unless spi nal reconstructions from helical CT of chest/abdomen available \200\223 if so omit) radiographs. 2) Consider thoracolumbar AP + lateral radiographs if appropriate mechanism. Await improved GCS and apply 4 clinical pre-conditions again. If satisfied, imaging normal and no signs o f injury the spine may be regarded as stable and uninjured. Close observation during mobili zation is essential* lateral radiographs. 3) If ALL of above satisfied, and no external signs of injury the spine may be regarded as sta ble and uninjured. Close observation during mobilization is essential though will be limite d in this group of patients \200\230Weakness, paraesthesia or pain may indicate a missed injury Neurological deficit referable to the spine requires urgent consideration of MRI Management of a detected injury must involve a senior neuro, spinal or orthopedic surgeon. Units unab le to provide helical CT may utilize directed CT scanning and radiographs: please refer to text. Helical CT of the chest and abdomen may generate reconstructions sufficient to replac e radiographs of the thoracolumbar spine. (Morris C, Guha A, Farquhar / 2004) Fig. 28.3.1 ICS \202 owchart. Autonomic hyper-re \202 exia This starts within 6 months of SCI after the recovery from sp inal shock. It is normally signi \201 cant if the injury is above T6. Stimulation (e.g. bl adder/bowel distension, cutaneous, surgery) below the level of injury leads to a supranorma l autonomic response. Intense vasoconstriction causes severe hypertension as a result of an excessive sympathetic efferent response, increasing risks of cerebral events (stroke, seiz ures). Paraplegics may display re \202 ex vasodilata- tion and bradycardia above the injur y level. weeks or until the patient is able to mobilize. If a PE is diagnosed with cardiovascular st ability, anticoagulation should be commenced. Contraindications to anticoagula- tion may ne cessitate an IVC \201 lter. Drugs The use of steroids in SCI has been studied. The series of NACSIS trials has shown so me motor improvement with methylprednisolone started within 3 \200\2238h of injury. Further reading Ball PA. Critical care of spinal cord injury. Spine 2001; 26 (24 Suppl): Venous thromboembolism There is a substantial risk of thromboembolic disease in SCI. Spinal fractures double the risk whilst SCI trebles it. The use of mechanical devices (TEDS, pneu matic compres- sion systems) alone are insuf \201 cient to provide prophylaxis. In view of potential hemorrhage or urgency of surgery, there is often apprehension in starting antico agulant ther- apy in patients with spinal fractures. The risk of developing DVT within the \201 rst 72h after injury has been shown to be low, and mechanical devices alone may suf \201 ce. Following this, anticoagulants, e.g. LMWH, should be considered for 8 27 \200\22330. Bracken MB, Shepard MJ, Holford TR, et al. Administration of meth- ylprednisolone for 24 or 48 hours or tirilazad mesylate for 48 hours in the treatment of acute spinal injury. JAMA 1997; 277: 1597 \200\223604. Jackson A, Groomes T. Incidence of respiratory complications fol- lowing spinal cord injury . Arch Phys Med Rehabil 1994; 75: 270 \200\2235. Morris C, Guha A, Farquhar I. Evaluation f or spinal injuries among unconscious victims of blunt polytrauma: a management guide- line for intensive care. ICS. 2005. 488 B WINTER, S SARKAR & H PATTANI Chest trauma \200 \200 \200 Blurred outline of arch or descending aorta First rib fracture Left apical haematoma Right displacement of mid-esophagus (detected by NG tube) Chest trauma can cause rapid deterioration and death from any part of ABC. 25% of all traum a deaths are caused by thoracic injury. 11% of pre-hospital mortality is due to penetrating chest trauma, often due to great vessel or heart injury, pneumothorax or airway obstructio n. It is mandatory to be aware of the major life-threatening inju- ries and their subsequen t management on the ICU. The polytrauma patient is unlikely to have an isolated chest injur y, so diagnosis and management of other injuries should be addressed. The majority of chest injuries can be treated with simple interventions such as chest drainage. Only 15% of pati ents require surgical intervention (thoracotomy or sternotomy). Thoracotomy is still the pr eferred route for massive hemorrhage, but many procedures, particularly diagnostic, are now undertaken by video thoracoscopy. Initial examination includes a CXR, but the nature of in ju- ries often necessitates CT of the thorax. This accurately detects pulmonary contusions, pneumothorax, haemotho- rax, pneumomediastinum and great vessel injuries. There is increas ing use of thoracic ultrasound in critical care, which may mean that pnemothoraces and othe r injuries may be detected more quickly. Either helical CT with contrast or aortography can be used to con \201 rm aortic injury. T OE is useful in cardiovascularly unstable patients, and is more sensitive than CT in diagno s- ing intimal/medial layer injuries. Treatment has recently moved away from timely surgery to non-surgical and delayed management. Major trauma patients have been seen to bene \201 t from deferred repair. In injuries to the intima or media, medical management similar to descending thoracic aortic aneurysm may be employed: avoiding hypertension by maintaining M AP 60 \200\22370mm Hg with -blockers and vasodilators. A thoracic surgical opinion is req uired to decide treatment options. Flail segment This is due to a considerable force applied to the torso causing \211 2 ribs to fracture in \211 2 places. Fracture of >6 ribs is associated with a steep increase in mortality, which may be reduced with epidural analgesia. The main prob- lem caused by such a direct force is parenchymal lung injury beneath the \202 ail segment, leading to pulmon ary contusion. Clinical approach Tension pneumothorax Life threatening \200\224requires immediate treatmen t. An undi- agnosed simple pneumothorax on admission may tension with IPPV on the ICU, with deteriorating hypoxia, tachycar- dia and high airway pressures. The presence of a chest tu be does not guarantee protection against tensioning, as tubes may block or kink. The diagno sis is suggested by absence of ipsilateral breath sounds, hyper-resonant percussion note, t rachea deviation (late) to the contralateral side and dis- tended neck veins (which may not be present if the patient is hypovolaemic). Treatment is initially with a large bore, e.g. 14G, IV cannula inserted in the 2nd intercostal space mid-clavicular line (therefore conve rting to an open pneu- mothorax), followed by a chest drain. Pulmonary contusion Injury to the lung tissue increases pulmonary vascular per- meability a nd protein- \202 uid leak into the alveolus, affecting the quality of surfactant. Reduced lung compliance and shunt lead to hypoxaemia. Contusions associated with major chest injury (multiple rib fractures, haemothorax, pneumothorax) are associated with increased mortalit y and are often underestimated on CXR. Achieving adequate ventilation in these patients is often dif \201 cult. Alongside other injuries such as brain or spinal, a compromise has to be reached for instituting lung-protec- tive strategies. Modes of ventilation may begin wi th NIV/ CPAP and escalating through IPPV, individual lung ventila- tion, HFOV and ECMO. Add itional therapies include pron- ing (which may be impossible in this patient group). The tr eatment does not differ substantially from that of other form of restrictive lung injury su ch as ARDS. Haemothorax Blood collecting in the pleural space can result from both blunt and penetratin g trauma. Initial treatment is with chest drainage. If the initial loss is \211 1500ml or ongoing haemor- rhage of >200ml/h for 4h, surgical intervention is indicated. Prompt evacua tion of haemothorax decreases later com- plications including empyema and entrapped lung. B eware intercostal tubes blocked by blood clot which may mislead as to bleeding rate. Diaphragmatic rupture This is uncommon and tends to occur alongside other tho- racoabdomina l injuries. The nature of the injury leads to a high morbidity and mortality. Diagnosis is usually through CT or ultrasound. Repair is surgical. Aortic injury The thoracic aorta is \201 xed at 3 distinct points: aortic valve, ligament um arteriosum and diaphragmatic hiatus. Sudden deceleration causes mobile parts of the aort a to move relative to \201 xed parts, leading to shear forces and tearing. The majority o f traumatic ruptures occur at the isthmus. This is situated immediately distal to the origi n of the left subclavian artery, at the junction of the \201 xed descending aorta and mob ile aortic arch. Widened mediastinum on CXR should raise suspicion of aortic rupture. Other radiographic features include: \200 \200 Air embolism Air entering the vascular compartment is potentially fatal. It may present wit h sudden cardiovascular or neurological collapse. Clinical features also include retinal ve ssel air and haemoptysis. Positive pressure ventilation is detrimental and may worsen sympt oms. One-lung ventilation may be utilized in unilateral injury. If both lungs are affected, low ventilation pressures should be instituted to reduce the possibility of further air en tering the circulation. Negative pressure spontaneous breathing is ideal. HBO should be con sidered in cerebral air embolism or signi \201 cant pulmo- nary air embolism, to reduce th e size. Left haemothorax Depressed left main bronchus 489 CHAPTER 28.4 Chest trauma Cardiac tamponade This should be suspected in any hypotensive patient with raised venous pr essure following thoracic trauma, with pneumothorax ruled out. TTE or TOE is used for diagn osis. In the presence of a suitably quali \201 ed thoracic surgeon, limited left thoracoto my is the treatment of choice, but needle pericardiocentesis may buy time in other hands. Oesophageal injuries These tend to occur secondary to penetrating, rarely blunt, injury. Th e morbidity and mortality is due to the systemic response to GI contents in the mediastinum . Clinical fea- tures include retrosternal pain, dysphagia and subcutane- ous emphysema. CX R features include pneumomediastinum, subcutaneous emphysema, mediastinal \202 uid levels , pleural effusions (more left sided) and pneumo/hydrothorax. Diagnosis is by contrast swal low or careful endoscopy, fol- lowed by surgical repair. Myocardial contusion Following chest trauma, myocardial contusions are rela- tively common. Clinical features include arrhythmias and cardiac failure. Following direct sternal force, the right ven- tricle is most commonly injured. Cardiac troponin assays (as opposed to CK- MB) are highly speci \201 c and sensitive for myocardial injury. However, non-cardiac inju ries and severe shock may lead to increased levels. Whilst TOE is sensitive to identify are as of wall motion abnormality, it is not spe- ci \201 c for myocardial injury. TTE is rela tively insensitive. Patients who display ECG abnormalities should be observed and ECG monit ored for at least 24h. Differentiating between contusion and MI can be difficult. It can be achieved by MRI angiography. Further reading Cain JG, Tesfaye Y. Pulmonary trauma. Curr Opin Anaesthesiol 2001; 14: 245 \200\2239. Goettler CE, Fallon WF. Blunt thoraco-abdominal injury. Curr Opin Anaesthesiol 2001; 14: 237 \200\22343. Kaye P, O \200\231Sullivan I. Myocardial contusion: emergency investigation and diagnosis. Emerg Med J 2002; 19: 8-10. Flagel BT, Luchette FA, Reed RL, et al. Half-a-dozen ribs: breakpoint for mortality. Surgery 2005; 138: 717 \200\22325. 490 T PARKE Pelvic trauma Pelvic fractures account for 3% of skeletal injuries. Stable fractures are low energy injur ies which are not life- threatening, and will not be discussed. Unstable fractures are high energy injuries associated with major soft tissue damage, and frequently other injuries (a bdominal, long- bone, spinal, thoracic and cranial). Pelvic trauma may also damage the uret hra and genitalia, rectum, bladder, per- ipheral nerves and blood vessels Patients presenti ng with unstable pelvic fractures and shock (1 \200\2232% of all pelvic injuries) have a mo rtality of 50%, and require aggressive management. Open pelvic fractures are rare (2% of ca ses) but carry a high mortality. If urethral injury is suspected, urinary catheterization is contraindicated until a retrogr ade urethrogram has been performed. Resuscitation Fluid loading via two large bore IV cannulae should follow ATLS guidelines. B leeding is venous in 80 \200\22390% of cases, from the fracture sites and damaged venous pl exi. Such patients respond transiently to \202 uids. However, pressure- induced tamponade will not occur in the retroperitoneum, as the blood tracks cranially (chimney effect). Ong oing bleeding can result in progressive acidosis, coagulopathy, hypothermia and abdominal c ompartment syndrome. In the emergency room, a folded sheet wrapped around the pelvis, and s ecured with a clamp, acts as an effective pelvic sling. By reducing of the fracture, and po ssibly by reducing pelvic volume, blood loss is reduced. Military ant- ishock trousers are associated with signi \201 cant complica- tions, and are no longer recommended. Mechanisms Unstable pelvic injuries may be suspected in the following: crush injuries, fall s, pedestrians hit by a vehicle, motorcycle accidents and ejection from a vehicle. Since th e pelvis is a ring, displacement requires 2 separate fractures. The Young \200\223Burgess c lassi \201 cation de \201 nes the following frac- tures as unstable: \200 Stopping the bleeding Once emergency measures have been instituted, the prior- ity is to st op the bleeding. It should be remembered that massive bleeding from pelvic fractures is unu sual compared with other sites, particularly the abdomen. Bleeding often occurs from more t han one site. Lateral compression fractures (types II and III) break the ring at the weakest point, the p ubic rami, in combination with iliac wing fractures and sacroiliac joint disruption (windsw ept pelvis). Anterior \200\223posterior compression fractures (types II and III) separate t he symphysis pubis and disrupt the sacroiliac joints (open book). Vertical shear forces fra cture the pubic rami vertically, and separate the symphysis, and sacroiliac joints. Vertica l fractures of the ilium and sacrum are rare, External \201 xation An external \201 xation device should be applied as soon as possib le in patients with hypotension and unstable pelvic fractures. Blood loss is reduced by re- apposing the bony surfaces and controlling venous bleeding. Such a device should also be ap plied in patients with unstable pelvic frac- tures who require a laparotomy, prior to skin incision. A pelvic C-clamp gives improved stabilization of the poste- rior pelvis, but is n ot applicable to all fractures. Fractures which increase pelvic volume (vertical shear, open book) result in larger transfu sion requirements. However, there is a poor correlation between the type of fracture and th e need for emergency haemostasis. Initial management Initial management should follow ATLS principles. Laparotomy Following external \201 xation, the next decision is whether a laparotomy is r equired. A laparotomy is indicated for intra- abdominal bleeding, perforated bowel and a ru ptured intra-abdominal bladder. However, the diagnosis of abdom- inal bleeding is not easy in the presence of a fractured pel- vis. The investigation of choice is a contrast CT scan, but many patients are too unstable for this to be performed safely. Ultrasound (FAST) scan ning can exclude haemotho- rax and intraperitoneal \202 uid, but lacks sensitivity in thi s situation. The most reliable test is a supraumbilical perito- neal tap, which is positive if 5 \200\22310ml of frank blood or GI contents is aspirated. Microscopy of lavage \202 uid is often positive for red cells in the absence of intra-abdominal bleeding, and does no t mandate a laparotomy. If a laparot- omy is performed, pelvic packing (see below) can be u ndertaken at the same time. Primary survey Patients in shock require simultanous \202 uid resuscitation and rapid ide nti \201 cation of possible causes. Clinical signs of a pelvic fracture include obvious de formity, and shortening or rotation of the leg. Bruising of the external genitalia and loin s, although speci \201 c, can be delayed. In the absence of obvious signs of fracture, pel vic instability may be detected by applying anterior \200\223posterior pressure, springing the iliac crests and pulling on the leg to detect axial instability. These maneuvers risk e xacerbating the bleeding, and should be performed only once, if at all. An AP X-ray of the pelvis (and chest) is an essential adjunct to the primary survey. Separation of the symphys is pubis by >1cm implies serious disruption. A rectal examination is essential to assess bl eeding, perfo- ration by bony fragments, a palpable pelvic haematoma or fracture, and anal tone. Urethral injury is much nore common in men, but may occur in women. Signs include: \200 \200 \200 Angiographic embolization If a laparotomy is not indicated, but evidence of bleeding contin ues, pelvic angiography with a view to embolization can be considered. However, shock due t o arterial bleed- ing accounts for only 10 \200\22320% of cases, and the type of frac- ture does not help predict the presence of arterial injury. One approach is to perform angiogra phy in patients after external fixation, who can be stabilized, but continue to require blo od transfusion at a rate of 1 \200\2232 units/h. Perineal bruising and scrotal haematoma Blood at the external urethral meatus High riding p rostate 491 CHAPTER 28.5 Pelvic trauma reduces hospital stay and long-term disability. However, the surgery can be challenging and lengthy, and should only be undertaken in stable patients. These patients can be safely transported to the angiography suite. The arteries most common ly damaged are branches of the internal iliac, the pudendal (anterior injuries) and the sup erior gluteal (damage to the sciatic notch). Angiographic embolization is unlikely to be pr actical in patients who are in extremis, losing up to 8 units/h. In these patients, pelvic packing at laparotomy can be considered. Complications Sepsis Haematoma resulting from pelvic fractures may become infected and form abscesses. Other local sources of infec- tion include \201 xation devices and wounds. If undiagnosed, extraperitoneal rupture of the rectum may form a pelvic abscess and systemic sepsis. Pelvic packing Laparotomy has traditionally not been indicated for a frac- tured pelvis alo ne, and hypogastric artery ligation is known to be ineffective. More recently a combination of external \201 xation, or C-clamps, with presacral and paravesical pack- ing has been employed in patients in severe shock, in whom the mortality is very high. Temporary aortic clamping can allow visualization and access. The rationale is that of \200\230dam- age con trol surgery \200\231; performing rapid life-saving interven- tions without attempting de \201 nitive treatment. Thromboembolism Thromboembolism is a major risk following trauma, and particularly followin g pelvic fractures, due to immobility, and damage to blood vessels. Prophylaxis should be g iven depending on other injuries, according to local protocols. Doppler ultrasound will det ect thrombi in the leg, but will not detect pelvic thrombi, which are more clinically signi \201 cant. Secondary survey The secondary survey is undertaken once life-threatening injuries have bee n stabilized. The purpose is to identify all other injuries. The urethra, bladder, rectum a nd neurovas- cular structures may all be damaged by pelvic fractures due to deformity, tear ing or penetration by bony fragments. In stable patients, a CT scan is the investigation of choice for de \201 ning the extent of these injuries. Pain Chronic pain syndromes may follow pelvic fractures, often due to damage to the sacroil iac joint, or leg-length discrepancies. Prognosis Mortality is primarily determined by the severity of the associated injuries, rat her than the pelvic fracture per se. Mortality is low (3 \200\2234%) in the absence of shoc k. Mortality is increased in the presence of a head injury, shock on pres- entation and inc reasing transfusion requirements. Those presenting in shock have a mortality of 50%. Poster ior pel- vic fractures have higher transfusion requirements and a higher mortality. Bladder, urethral and rectal injuries Extraperitoneal bladder rupture (80%) is more common than intraperitoneal rupture (20%), and in the majority of cases resolves with drainage and irrigation. Intraperitoneal bladder rupture requires emergency laparotomy. One- \201 fth of patients with bladder lesions have urethral injuries. These are managed initially by sup rapubic drainage, but complete tears will require subsequent urethroplasty. Impotence is as sociated with urethral injuries. Rectal per- foration is associated with bladder and urethr al injuries, and is most commonly extraperitoneal. A defunctioning colostomy may be require d. Further reading Advanced Trauma Life Support for Doctors, ATLS, faculty course manual. Chicago: American College of Surgeons, 2004. Gansslen A, Giannoudis P, Pape H-C. Hemorrhage in pelvic fracture; who needs angiography? C urr Opin Crit Care 2003; 9: 515-23. Nerve injuries The sacral plexus or sacral nerve roots can be damaged by fractures of the s acrum or sacroiliac joints. This results in loss of anal tone and perineal anesthesia. The sciatic nerve can be injured by fractures of the posterior acetabulum or greater sciatic no tch. The L5 root may also be damaged with sacral fractures. Injuries to the obdurator nerve are easily overlooked. Incaglioni P, Viggiano M, Carli P. Priorities in th management of severe pelvic trauma. Curr Opin Crit Care 2000; 6: 401 \200\2237. Shepherd C. eMedicine. Pelvic fractures. http://www.emedi- cine.com/emerg/topic203.htm. Thornton DD. eMedicine. Pelvic ring fractures. http://www. emedicine.com/radio/topic546.htm. Wheeles \200\231s textbook of orthopedics.; pelvic fractures menu. http://www.wheelessonline.com/ortho/pelvic_ fractures. De \201 nitive care Early internal \201 xation of unstable pelvic ring fractures with pl ates and screws allows more rapid mobilization, and 492 P FERRIS, R DUNCAN, & P NIGHTINGALE Burns \200\224 \202 uid management Introduction In the decades from 1930 to 1950 hypovolaemic shock and shock-induced renal fa ilure were the leading causes of death following signi \201 cant burn injury. It was then discov- ered that mortality could be improved by \202 uid resuscita- tion to replace the considerable post-burn intravascular \202 uid de \201 cits. Since then, numerous \202 uid resuscitation strat- egies have been developed. a lower risk of infection than the femoral veins, but choice is generally dictated by the d istribution of the burn. Full aseptic precautions are essential, and meticulous care of any central venous cannula is necessary to prevent infec- tion. Ultrasound guidance is recomme nded because even at an early stage, constricting burns and oedema can dis- tort the anatom y. Urine output is an important indicator of adequate res- uscitation, so all patients with burns of >20% or so TBSA should have a urinary catheter inserted early, as oedema formatio n can make insertion dif \201 cult later on. Oedema formation can be extensive and progres sive, so care must be taken when using any circumferential dress- ings (e.g. to secure IV a ccess) to avoid any tourniquet effect. Progressive oedema formation can also kink or dislod ge peripheral and central cannulae from the vein, so a high index of suspicion and regular assessments are necessary.