The Revised Trauma Score The Revised Trauma Score (RTS) is used to assess the physiological disturbance of a trauma patient. The score is calculated from the respira- tory rate, syst olic BP and GCS. Each of these parameters are assigned a code (value) to which a weighting factor is applied. The 3 resultant scores are then added together to give the RTS. The RTS ranges from 0 (worst possible) to 7.84 (best). TRISS methodology Combining the ISS with the RTS and adding a weighting factor according to the age of the patient, it is possible to c alculate a \200\230Probability of Survival \200\231 (Ps) for each patient, based upon the national norm. Patients who survive with Ps<0.5 are regarded as \200\230unexpected survivo rs \200\231; patients who die with Ps > 0.5 as \200\230unexpected deaths \200\231. By anal yzing the results of treating a large number of patients, TRISS methodology may be used to compare \200\230performances \200\231 (eg of one hospital against the national norm). 324 CHAPTER 8 Major trauma Airway obstruction: basic measures Severely injured patients die rapidly unless oxygenated blood reaches the brain and other vital organs. Clear, maintain, and protect the airway, en sure that ventilation is adequate and give O 2 in as high a concentra- tion as possible. Th e most urgent priority is to clear an obstructed airway, but avoid causing or exacerbating any neck injury: instruct someone to hold the head and neck in a neutral position until the neck is satisfactorily immobilized. Ensure you always wear personal protective equipment. When treating any seriously injured patient, always ensure that O 2 , suction and airway eq uipment are readily available. Get senior ED ICU/anesthetic help early if a patient with a serious airway problem arrives or is expected. Causes of airway obstruction \200 Coma from any cause can result in airway obstruction an d loss of protective airway re \202 exes. Blood or vomit may block the airway. \200 The airway may be disrupted by trauma of the fa ce or larynx, or may be occluded by a haematoma or by oedema following burns. Assessment of airway obstruction Talk to the patient and see if he responds. A lucid reply shows that the airway is patent, that he is breathing and that some blood is reaching the b rain, at least for the moment. Ensure that the neck does not move until it has been checked and cleared of injury ( b p.320). Look and listen to check how the patient is breathing. C omplete airway obstruction in someone who is still trying to breathe results in paradoxical movements of the chest and abdomen, but no breath sounds. Gurgling, snoring and stridor ar e signs of partial obstruction. Management of airway obstruction \200 Look in the mouth and pharynx for FBs, blood, and v omit. The tip of a laryngoscope may be useful as an illuminated tongue depressor. Remove any FB with Magill \200\231s forceps and suck out any liquid with a large rigid suct ion catheter. See if the patient responds and has a gag re \202 ex, but beware of precipit ating coughing or vomiting. If vomiting occurs, tilt the trolley head down and suck out any vomit. \200 Lift the chin and use the jaw thrust maneuver (see opposite) to open the airway, but do not \202 ex or extend the neck. After any airway intervention, look, listen, and feel to reassess airway patency and ef \201 cacy of breathing. If the gag re \202 ex is absent or poor, insert an oropharyngeal airway (see opposite). Th is helps to hold the tongue forwards, but can cause vomiting or coughing if there is a gag re \202 ex. If the gag re \202 ex is present or the patient \200\231s jaws are clenched, consider a nasopharyngeal airway . Although a nasopharyngeal airway is useful in some situa tions, avoid its use if there is evidence of severe facial or head injury. If the airway is now patent and the patient is breathing, give high concentration O 2 (15L/min via a non-rebreathing reservoir mask). If the airway is patent, but breathing inadequate, ventilate the patient with O 2 bag and m ask device and prepare for tracheal intubation. If possible, one person should hold the mas k on the face with both hands to ensure a good seal, whilst a second person squeezes the ve ntilation bag. 325 AIRWAY OBSTRUCTION: BASIC MEASURES Insertion of oropharyngeal airway \200 Select the appropriate size of airway. \200 Hold an airway against the patient \200\231s face. A correctly sized airway reaches from the co rner of the mouth to the external auditory canal. A large adult usually needs a size 4 airw ay, most men require size 3, some women need a size 2. An incorrectly sized airway may make the obstruction worse, rather than better. Open the patient \200\231s mouth and use a rigid suction catheter with high power suction t o suck out any \202 uid or blood from the oropharynx. \200 Insert the oropharyngeal air way \200\230upside down \200\231 for 4 \200\2235cm (half way), then rotate it 180 and insert it until the \202 ange is at the teeth. In children, use a laryngoscope as a tongue depressor and insert the airway the \200\230correct way up \200\231 to avoid trauma to the palate. \200 Re-check the airway and breathing and give high \202 ow O 2 . \200 Ventilate the patient if brea thing is inadequate. Insertion of nasopharyngeal airway \200 Select an appropriate airway, usually a 7.0mm for adult males and a 6.0mm for adult females. A safety pin through the \202 ange end will p revent displacement into the nose or nasopharynx. Lubricate the airway with water or a water-soluble lubricant. \200 Insert the tip of the airway into one nostril and direct the airway posteriorly, aiming the tip at the tragus of the ear. The airway should slide easily into the nose until the \202 ange abuts the nostril and th e tip is just visible in the pharynx. Never force a nasopharyngeal airway into the nostril \200\224 any bleeding produced will markedly aggravate the airway problem. Re-check the airway and breathing and give high \202 ow O 2 . Jaw thrust maneuver The aim of this is to open the upper airway with minimum movement of the cervical spine. Place the fore \201 ngers of both hands immediately behind the angles of the mandible and push the mandible anteriorly. This will lift the tongue anteriorly and thus away from the posterior pharyngeal wall. Tracheal intubation in trauma An injured patient who has no gag re \202 ex needs tracheal intubation to maintain the airway and protect it against blood and vomit. Intubation may al so be needed because of: apnoea (after initial ventilation with a bag-valve-mask), respirat ory inadequacy, to prevent potential obstruction from facial burns or to allow manipulation of ventilation in patients with i ICP). Intubation in such circumstances requires emergenc y anesthesia: suitable expertise, appropriate equipment and assistance are essential ( b p. 312). An assistant must hold the head to prevent movement of the neck during intubation, wh ile another assistant provides cricoid pressure. Con \201 rm correct tracheal tube placeme nt by: \200 Seeing the tube pass through the cords. \200 Observing symmetrical chest mo vement. \200 Listening over both axillae for symmetrical breath sounds. \200 Con \201 rming placement with end-tidal carbon dioxide (CO 2 ) monitoring. If airway obstruction is complete, the obstruction cannot be relieved and intubation is impossible, an urgent surgic al airway is needed ( b p.326). 326 CHAPTER 8 Major trauma Airway obstruction: surgical airway Surgical cricothyroidotomy or jet insuf \202 ation of the airway via a needle cricothyroidotomy is needed if the airway is obstructed by trauma, oedema or infection, and the trachea cannot be intubated. Emergency tracheostomy is not ind icated in this situation because it is too time- consuming to perform and the necessary exp ertise may not be available. Needle cricothyroidotomy This is a rapid temporizing measure whilst preparation is made for a de \201 n- itive airway (eg surgical cricothyroidotomy). Jet insuf \202 ation via a ca nnula placed through the cricothyroid membrane can provide up to 45min of oxygenation of a patient with partial airway obstruction (Fig. 8.1 ). \200 Use a large IV cannula-over-nee dle (adults: 12 or 14G; children: 16 or 18G), attached to a syringe. If right-handed, stand on the patient \200\231s left. \200 Palpate the cricothyroid membrane between the thyroi d and cricoid cartilages. Hold the cricoid cartilage \201 rmly with the left hand. Pass the needle and cannula at a 45 angle to the skin in the midline through the lower h alf of the cricothyroid membrane into the trachea. \200 Aspirate whilst advancing the nee dle. Aspiration of air con \201 rms entry into the trachea. Withdraw the needle whilst adv ancing the cannula down into position in the trachea. Connect the cannula via a Y connector or O 2 tubing with a side hole to wall O 2 at 15L/min (in a child the rate should initially be set in L/min at the child \200\231s age in years, increasing if necessary until capable of causing chest movement). Hold the cannula \201 rmly in position. Occlude the side hole or the end of the Y connector with a thumb for 1 in 5sec to give intermittent insuf \202 ation of O 2 . Spontaneous breathing through the small airway of a cannula is very dif \201 cult, but the patient should be able to exhale partially in the 4sec between jets of O 2 . However, CO 2 retention occurs and limits the time that jet insuf \202 ation can be tolerated. Proceed immediately to a de \201 nitive airway (call a senior ENT or maxillofacial surgeon). Surgical cricothyroidotomy This technique is not appropriate in children aged <12 years. \200 Stand on the patient \200\231s right. Feel the thyroid and cricoid cartilages and the cricothyroid membrane between them. Clean the area and give LA (if the patient is conscious and time allows). \200 Hold the t hyroid cartilage with the left hand and make a transverse incision through the skin and the cricothyroid membrane. Use a tracheal dilator or curved artery forceps to open the hole into the trachea. Do not worry about any bleeding at this time. Insert a lubricated tracheostomy tube (5 \200\2237mm diameter) through the cricothyroid membrane into the trachea. Remove the introducer from the tracheostomy tube, in \202 ate the cuff and connect the tube to a catheter mount and ventilation bag. Con \201 rm correct placement with end-tidal CO 2 monitoring. \200 Ventilate the patient with O 2 and secure the tracheal tube. \200 Examine the chest and check for adequacy of ventilation. 327 AIRWAY OBSTRUCTION: SURGICAL AIRWAY Thyroid cartilage Cricoid cartilage Trachea Cricothyroid membrane Fig. 8.1 Needle cricothyroidotomy. Fig. 8.2 Surgical cricothyroidotomy. 328 CHAPTER 8 Major trauma Tension pneumothorax Tension pneumothorax is a life-threatening emergency and requires prom pt recognition and treatment. It occurs when gas progressively enters the pleural space, bu t is unable to leave. Increasing pressure causes complete lung collapse on the affected sid e and ultimately pushes the mediastinum to the other side. Movement of the mediastinum lead s to kinking of the great vessels, thereby d venous return and cardiac output. Additional c ompromise results from compression of the lung on the other side, particularly in patients undergoing IPPV. The process leading to tension pneumothorax may occur very rapidly, culmin ating in cardiac arrest within minutes. Causes Tension pneumothorax is seen most frequently following trauma, but it may also occur iatrogenically after attempted insertion of a central venous line ( b p.56). A small (perh aps unsuspected) simple pneumothorax is particularly likely to become a tension pneumothora x when IPPV is commenced. Features \200 Dyspnoea, tachypnoea, and acute respiratory distress. \200 Absent breath sounds on the affected side. \200 Hyper-resonance over the affected lung (dif \201 cult to demonstrate in a noisy environment). Distended neck veins (unless hypovolaemic), tachycardia, hypotension, and ultimately, loss of consciousness. Tracheal deviation away from the affected side (this is rarely clinically apparent). i Airway pressure in a patient receiving IPPV. Diagnosis This is entirely clinical : do not waste time obtaining X-rays. Treatment \200 Apply high \202 ow O 2 by face mask. \200 Perform immediate decompress ion by inserting an IV cannula (16G or larger) into the second intercostal space in the mid -clavicular line, just above the third rib (to avoid the neurovascular bundle; Fig. 8.3 ). Withdraw the needle and listen for a hiss of gas. Tape the cannula to the chest wall. \200 Insert an axillary chest drain on the affected s ide immediately ( b p.336). Remove the cannula and apply an adhesive \201 lm dressing. \200 Check the patient and o btain a CXR. Note : the risk of causing a pneumothorax by needle decompression in a patient who did not have one is approximately 10 % . If the patient is very muscular or obese, con sider using a longer cannula than normal (e.g. central venous line) to ensure that the pleu ral cavity is reached. 329 TENSION PNEUMOTHORAX Mid-clavicular line Fig. 8.3 Site for needle decompression of right tension pneumothorax. 330 CHAPTER 8 Major trauma Chest wall injury 1 Background Blunt chest wall trauma is extremely common \200\224 both a s an isolated injury and as part of multiple injuries. It can cause great morbidity in the elderly. Isolated rib fracture A history of trauma with subsequent musculoskeletal pain suggests rib fracture. The diagnosis is con \201 rmed by localized chest wall tenderness \200\224 the diagnosis of a single rib fracture is a clinical one. Check for features which are suggest ive of pneumothorax (dyspnoea, d air entry, see b p.334), secondary pneumonia or multiple r ib fractures, and if any are present, obtain a CXR. Treat uncomplicated isolated rib fracture with oral analgesia (eg co-codamol NSAID). War n the patient that the rib may remain painful for \211 3 weeks and to seek medical advice if additional symptoms develop. Multiple rib fractures Observe the chest wall carefully for possible \202 ail segment, an d look for clinical evidence of pneumothorax or, in late presentations, secondary pneumonia . Check SpO 2 , ABG, and obtain a CXR. Note that up to 50 % of rib fractures may not be app arent on CXR. Treat Flail segment and pneumothorax ( b p.332). Treat patients with uncompli cated multiple rib fractures according to the presence of other injuries and pre-existing m edical problems as follows: In patients with other injuries requiring IPPV, discuss the potential need for chest drains with the ICU team ( i risk of pneumothorax). Patients with pre-existing pulmonary disease and limited respiratory reserve require admission for analgesia and physiotherapy. Patients with chest infection often require admission for analgesia, antibiotics and physio therapy, depending upon past medical history, clinical, and radiological \201 ndings. 331 CHEST WALL INJURY 1 Sternal fracture Sternal fracture frequently occurs during road traf \201 c collisions, ei ther due to impact against the steering wheel or seat belt. The injury may be associated wi th myocardial contusion, great vessel injury and spinal injury (see below). Features Anterior chest pain with localized tenderness over the sternum. Investigations \200 Place on a cardiac monitor. \200 Record an ECG to exclude arrhythmi as, MI ( b p.70) or myocardial contusion (look for ST changes, particularly elevation). Con sider further investigation with echocardiography. Check cardiac speci \201 c enzymes (troponins) if there are ECG changes. \200 Request CX R and lateral sternal X-ray: the latter will demonstrate the fracture (which is usually tra nsverse), the former, associated injuries. Treatment Provide O 2 and analgesia. Admit patie nts who have evidence of myocardial contusion or injuries elsewhere. Only consider discharg ing those patients who have an isolated sternal fracture, with a normal ECG, no associated injuries and normal pre-existing cardiopulmonary function. Patients who are discharged requ ire oral analgesia (eg co-codamol N SAID) and GP follow-up. Note Rarely, forced \202 exion of the chest causes a displaced sternal fracture with wedg e fractures of upper thoracic vertebrae. Check the spine carefully, ask about pain, and loo k for kyphosis and tenderness (which may not be apparent). Lateral thoracic X-rays often fa il to show the upper thoracic vertebrae, so if injury is suspected there, consider requesti ng a CT scan. 332 CHAPTER 8 Major trauma Chest wall injury 2 Flail segment Fractures of \211 3 ribs in 2 places allows part of the chest wall to move independently. This \202 ail segment usually indicates signi \201 can t injury to the underlying lung (typically pulmonary contusions). Large \202 ail segments occur laterally when several ribs on one side fracture anteriorly and posteriorly. Similar ly, an anterior \202 ail segment is produced by bilateral fractures of all ribs anteriorl y \200\224 in this case, the free portion comprises the sternum, costal cartilages, and th e medial parts of the fractured ribs (see Fig. 8.4 ). Presentation The \202 ail segment c auses pain and moves paradoxically compared with the rest of the chest wall, limiting the e ffectiveness of respiration. The diagnosis is a clinical one, but it can be dif \201 cult to make. Look tangentially at the chest for areas which move paradoxically (ie inwards duri ng inspiration and outwards during expiration). There may be associated features of respira tory distress (cyanosis, tachypnoea). Check for pneumothorax or haemothorax ( b p.334). Inv estigations Assessment of the extent of respiratory compromise is largely clinical, aided b y a few simple investigations: \200 SpO 2 on pulse oximetry. \200 ABG \200\224 the com bination of hypoxia and respiratory acidosis ( i p CO 2 , i H + ) indicates severe respiratory compromise. CXR will demonstrate fractures and associated injuries (eg pulmonary contusions, pneumothorax, haemothorax). Treatment \200 Provide high \202 ow O 2 and treat associated life-threatening problems. \200 Contact the ICU/anesthesia team and carefully consider the need for immediate or urgent tracheal intubation with IPPV. Careful observation and monitoring in an high dependency unit (HDU) or ICU is required. Consider inserting an intra-arterial line for frequent ABG analyzes. \200 Selected patien ts may bene \201 t from epidural analgesia in ICU. Lateral flail segment Anterior flail segment Fig. 8.4 Lateral (left) and anterior (right) \202 ail segments. 333 CHEST WALL INJURY 2 Ruptured diaphragm Left-sided ruptures predominate (75 % ). Major rupture of the diaphragm, with associated herniation of abdominal contents into the c hest, is a severe injury resulting from a signi \201 cant traumatic insult (often massive abdominal crushing). Depending upon the extent of the injuries, the patient may present wit h hypovolaemic shock and respiratory compromise. Note that a ruptured diaphragm may have so me clinical features similar to a tension pneumothorax. Call a surgeon and anesthetist : th e patient will require urgent intubation and IPPV. Minor rupture, with less dramatic herniation, may present in more subtle fashion and result from penetrating injury. The diagnosis is dif \201 cult to identify on CT scanning and is frequently missed initially \200\224 it is important because: \200 It is often associat ed with injury to both abdominal and thoracic contents. \200 There are possible late comp lications (eg bowel herniation/obstruction). \200 It does not heal spontaneously. Suspect a ruptured diaphragm from the mechanism of injury, and an abnormal or high hemi-diaphragm contour on erect CXR. Look for stomach or bowel loops in the chest: the gastric tube may be seen coiled in the intra-thoracic stomach. If a ruptured diaphragm is suspected, resuscita te the patient and refer to a surgeon. Oesophageal rupture Traumatic (non-iatrogenic) rupture of the esophagus is uncommon, but ma y follow blunt or penetrating injury. Suspect it if the patient complains of chest and back /neck pain in the presence of a normal ECG. Look for surgical emphysema in the neck. CXR ma y demonstrate pneumomediastinum (a layer of gas around the heart/mediastinum), a left sided pleural effusion or pneumothorax. Provide O 2 , IV analgesia, and start IV antibi- otics ( eg cefuroxime 1.5g). Resuscitate, treat other injuries, and refer to a cardiothoracic surge on. Boerhaave \200\231s syndrome is \200\230spontaneous \200\231 rupture of the esophagus asso ciated with overindulgence and vomiting. Patients are classically middle-aged and present w ith severe chest pain, signs of shock, and subcutaneous emphysema. If this condition is sus pected, treat as outlined above for traumatic oesophageal rupture. 334 CHAPTER 8 Major trauma Traumatic pneumothorax Background Pneumothorax frequently results from blunt injury with as sociated rib fractures or from penetrating injury (knife stabbing or gunshot wound). It may also be iatrogenic, secondary to attempted insertion of a central venous line. Clinical features Patients are likely to complain of symptoms relating to the associated in juries (eg rib fractures, b p.330). The degree of breathlessness resulting from a pneumotho rax depends largely upon its size. Other features may be present, including surgical emphys ema, cyanosis, d air entry over the affected lung. Severe dyspnoea and distended neck veins /hypotension suggest tension pneumothorax ( b p.328). CXR demonstrates the pneumothorax. Bo th inspiratory and expiratory X-rays are not required. Wherever possible, obtain an erect C XR. X-rays taken with the patient lying supine may not show a free lung edge, despite a con siderable pneumothorax, because in this position air tends to lie anteriorly in the pleural space. If there is no de \201 nite pneumothorax visible on a supine CXR, features which a re suggestive of a pneumothorax are: \200 Hyperin \202 ation of the affected hemithorax with depressed hemidiaphragm. \200 Double contour of a hemidiaphragm. \200 Basal hyperl ucency of the affected lung. \200 Visualization of apical pericardial fat tags. CT scan o btained to assess other injuries will easily demonstrate a pneumothorax. SpO 2 and ABG may reveal hypoxia. Treatment Tension pneumothorax is an emergency requiring immediate needle decompression ( b p.328). Provide O 2 and drain other traumatic pneumothoraces using a chest drain and open technique, as described on b p.336. Note: although not currently considered to be \200\230 standard practice \200\231, there is increasing experience with initially managing some pat ients who have isolated chest injury and small traumatic pneumothoraces in a conservative f ashion, using close observation and no chest drain. Further experience will be needed befor e this approach can be widely recommended. Patients who have multiple injuries and/or other injuries (particularly those requiring GA and IPPV) certainly require chest drain insertio n in the ED. 335 HAEMOTHORAX Haemothorax Blood may collect in the pleural cavity in association with a pneumothorax (hae mopneumothorax) or without (haemothorax). A large amount of bleeding into the pleural space suf \201 cient to produce hypovolaemic shock is termed massive haemothorax . Clinical features The clinical presentation is similar to that seen in traumatic pneumo- th orax, except that there may be dullness to percussion over the affected lung and, with mass ive haemothorax, evidence of hypovolaemia. CXR Blood from a haemothorax collects under the affected lung, showing up as i shadowing on a supine X-ray, with no visible \202 uid level. It may be very dif \201 cult to disting uish haemothorax from pulmonary contusions on supine X-ray, but haemothorax may produce blu rring of a hemidiaphragm contour or of the costophrenic angles. Treatment Give O 2 and insert 2 large venous cannulae (sending blood for X-matching). If hy povolaemic, start IV \202 uids before inserting a large ( \211 32FG) chest drain. Altho ugh it is common practice to try to direct the chest drain towards the diaphragm, this seld om makes a difference in practice \200\224 it is more important to use a chest tube of suf \201 cient caliber in order to minimize blockages due to blood clots. 336 CHAPTER 8 Major trauma Chest drain insertion Use the \200\230open \200\231 technique, as described below. Explain the procedure, obtain consent and con \201 rm that the patient has venous access, is brea thing O 2 , and is fully monitored. Ensure that all equipment is ready and a good light and assistance are available. Give adequate IV opioid analgesia to conscious patients as this procedure can be painful. \200 Abduct the ipsilateral arm fully. \200 Don a sterile gow n and gloves, and use a face shield to protect against blood splashes. Clean the skin with antiseptic and cover with sterile drapes. \200 Identify the 5th inter costal space just anterior to the mid-axillary line (count down and across from the angle o f Louis at the level of the 2nd rib) (Fig. 8.5 , top). Generously in \201 ltrate LA (1 % lidocaine adrenaline) under the skin and down to the periosteum at the upper edge of the 6th rib. Prepare the chest drain; remove and discard the trocar (in adults, use a size 28 \200\22332 FG; in children, use the largest size that will comfortably pass between the ribs). Make a 2 \200\2233cm skin incision in the line of the ribs (Fig. 8.5 ). \200 Use blunt di ssection with artery forceps to open the tissues down to the pleural space, just above the 6th rib. \200 Puncture the pleura with the artery force ps. \200 Insert a gloved index \201 nger into the pleural cavity to ensure there are no adhesions and that you are within the thoracic cavity (Fig. 8.5 ). Insert the chest drain ensuring that all drainage holes are inside the chest (typically \211\210 15 \200\22320cm in adults). Connect the drain to an underwater seal and look for \200\230swinging \200\231. \200 Sut ure the drain securely in place (eg with heavy silk) and cover with an adhesive \201 lm d ressing and adhesive tape (Fig. 8.5 ). Whilst securing it, get an assistant to hold the dra in so that it does not inadvertently fall out. It is useful to insert two untied sutures at the site of exit of the chest drain, so that these can be later tied to close the exit sit e when the drain is removed. Check the underwater seal is \200\230swinging \200\231 in the tube with respiration. \200 Listen for air entry and check the patient. \200 Obtain a CXR to con \201 rm placement : if the tube has been inserted too far (eg so that it is touching the mediastinum), pull i t back slightly and re-suture and secure in place. Afterwards, keep the water seal drainage bottle below the level of the patient. Avoid clamping the tube. Referral to a thoracic surgeon If the chest drain initially yields > 1500mL of blood, or su bsequently drains > 200mL/hr for 2hr, refer urgently to a thoracic surgeon for possible urg ent thoracotomy. Ruptured bronchus Persistent, continuing bubbling of gas through the underwater drain may r e \202 ect a major rupture of the tracheobronchial tree, especially if the lung fails to r e-expand. Bronchial rupture may also present with haemoptysis or tension pneumothorax. Invo lve a thoracic surgeon at an early stage. 337 CHEST DRAIN INSERTION Mid-axillary line 4th ICS 5th ICS Fig. 8.5 Chest drain insertion. 338 CHAPTER 8 Major trauma Pulmonary contusions and aspiration Pulmonary contusions High energy transfer during blunt injury (eg road traf \201 c collisions or high falls) often causes pulmonary contusions. S uspect these in all patients with \202 ail segments ( b p.332). Clinical features Pulmona ry contusions produce ventilation-perfusion mismatch which may lead to hypoxia and respirat ory distress, and i the likelihood of ARDS. Radiological appearances Pulmonary contusions m ay be visible on initial CXR as patchy opaci \201 cation. However, initial radiological ap pearances are non-speci \201 c and may be confused with those seen after pulmonary aspirat ion or haemothorax ( b p.335). X-ray changes resulting from pulmonary contusions tend to be progressive and become more prominent with time. Management Provide high \202 ow O 2 and check ABG to help assess the need for GA, trachea l intubation and IPPV. Involve ICU specialists early. Pulmonary aspiration ( b see p.112) I nhalation of vomit and other foreign material may add considerably to the damage resulting from the initial injury. Common associations \200 Inhalation of vomit after head injury with d conscious level and impaired protective laryngeal re \202 exes: gastric contents are particularly irritant to the respiratory tract. Inhalation of blood and teeth after facial trauma. \200 Inhalation of water and foreign m atter in near drowning ( b p.258). Presentation Suspect pulmonary aspiration from the histo ry, associated respiratory signs and X-ray appearance. The CXR may show diffuse opaci \201 cation affecting one or both lungs \200\224 the distribution depends upon the position at the time of aspiration. Management \200 Check SpO 2 , ABG, and obtain a CXR. \200 Provide high \202 ow O 2 . \200 Treat other injuries. \200 Consider the need for GA, tracheal intubation, and IPPV . Bronchoscopy may be needed to remove large FBs from within the bronchial tree. \200 Eve n if there is no urgent requirement for IPPV, remember that the respiratory problem is like ly to worsen (with development of infection/ ARDS), so involve the ICU team early. Do not give routine antibiotics, unless there is a speci \201 c indication, such as immers ion in sewage or in rat-infested water with the risk of developing leptospirosis (see b p.2 39). This page intentionally left blank 340 CHAPTER 8 Major trauma Penetrating chest injury 1 In the UK, unlike the USA, chest \200\230stabbing \200\231 is f ar more frequent than \200\230shooting \200\231. Both types of injury can pose a serious t hreat to life. Initial assessment and resuscitation Do not be misled by seemingly innocuous wounds. The si ze of the external wound has no correlation with the potential for internal injury. All pat ients need O 2 , venous access (send blood for cross-matching, or group and save) and resus citation according to an evaluation of the airway/ cervical spine, breathing, and circulati on. Remove all of the patient \200\231s clothes and log roll to check for wounds to the bac k of the trunk and perineum. Particularly in gunshot injuries, make a quick early check for evidence of spinal cord injury. Remember also that penetrating chest injury often involves the abdomen (and vise-versa). During initial assessment aim to exclude or identify and tre at the following: \200 Tension pneumothorax ( b p.328). \200 Sucking chest wound ( b p. 342). \200 Cardiac tamponade ( b p.342). \200 Massive haemothorax ( b p.334 and 335). F urther management depends partially upon haemodynamic status. The stable patient Many patients present without overt evidence of signi \201 cant injury: \200 Provide O 2 , secure venous access, and send blood for group and save. \200 Monit or SpO 2 , pulse, BP, and respiratory rate. \200 Administer minimal or no intravenous \202 uids. \200 Perform a FAST scan if possible to look for cardiac tamponade ( b p.346). Obtain a CXR (ideally postero-anterior (PA) erect). \200 Record an ECG. \200 Provide IV analgesia as required (see b p.320). \200 Consider tetanus status and the need for proph ylactic antibiotics (eg 1.5g IV cefuroxime \200\224 according to local policy). Cover the chest wound with a sterile dressing (for sucking chest wound \200\224 see b p.342). Drain any pneumothorax with a chest drain (having decompressed any tension pneumothorax \200\224 b p.328). Do not insert the drain through the wound (this i the risk of infection) . Refer all patients for admission, observation, formal wound cleaning, exploration, and clos ure. If the patient remains stable overnight, with no clinical or radiological abnormalitie s (on repeat CXR \211 6hr after the \201 rst), they may be safely discharged with arran gements for review. Carefully document the size, position and other features of the chest wound, remembering th e potential medicolegal signi \201 cance ( b p.402). 341 PENETRATING CHEST INJURY 1 The unstable patient Haemodynamic instability may be due to tension pneumothorax, massive h aemothorax, sucking chest wound, or cardiac tamponade. Treat each of these as outlined on b p.342 involving a senior surgeon at an early stage. Indications for thoracotomy Thoracotom y in theater will be required for signi \201 cant hemorrhage, which typically means: \200 > 1.5 L of free blood obtained by initial chest drainage, or. \200 > 200mL of blood dra ining per hr, via the chest drain. 342 CHAPTER 8 Major trauma Penetrating chest injury 2 Open chest injury An open wound between the pleural cavity and t he outside may cause respiratory insuf \201 ciency. When the chest expands on inspiration there is less resistance to air movement through the open chest wound than down the tracheo bronchial tree. Air \202 ow into the lungs is reduced and the lung collapses as air enter s the pleural space and produces a pneumothorax. Hypoxia develops rapidly. Features Look for respiratory distress, tachypnea, and cyanosis. Management \200 Provide high \202 ow O 2 . \200 Cover the chest wound with a square o f polythene or sterile dressing. \200 Secure 3 sides of the dressing to the chest wall wi th adhesive tape, leaving one side free. This will allow air to exit through the chest wall during expiration, but prevent air entry into the chest cavity. Insert a chest drain (not through the wound) to drain the pneumothorax. \200 Provide furt her resuscitation as necessary. \200 Call a thoracic surgeon to arrange formal wound clos ure. Cardiac tamponade Hemorrhage into the pericardial sac may compromise cardiac output. Contin uing bleeding leads to cardiac tamponade, culminating in cardiac arrest. Cardiac tamponade usually results from penetrating trauma but may occur after blunt trauma. Features Clinical diagnosis requires a high index of suspicion. The oft-quoted Beck \200 \231s triad comprises distended neck veins, hypotension, and muf \202 ed heart sounds. Ide ntifying muf \202 ed heart sounds is rarely easy in a noisy ED and neck veins may not be d istended in a hypovolaemic patient. Kussmaul \200\231s sign and pulsus paradoxus are classi cal, but rarely helpful. Investigation The investigation of choice is a FAST scan ( b p.346) in the ED resuscitation room to identify the presence of pericardial \202 uid. USS signs of cardiac tamponade in clude right ventricular collapse. Formal echocardiography is rarely available immediately. CXR and ECG are rarely helpful, but may exclude co-existent conditions (eg pneumothorax). Treatment \200 Provide O 2 , insert 2 IV lines, commence IV \202 uid infusion if severe ly shocked and monitor ECG. Request that the thoracotomy tray be made ready. \200 Contact the most senior available c ardiothoracic/general/trauma surgeon and anesthetist and alert the operating theater. If the patient \200\231s condition permits, arrange immediate transfer for thoracotomy in t heater. Theater thoracotomies have better outcomes than those done in the ED. 343 PENETRATING CHEST INJURY 2 If the patient deteriorates to a peri-arrest state, consider pericardiocen- tesis using a l ong 18G needle connected to a 20mL syringe and 3-way tap. Puncture the skin 1 \200\2232cm b elow the xiphisternum at 45 to the skin. Aspirate while advancing the needle cephalad, a iming towards the tip of the left scapula. ST and T wave changes, widened QRS or arrhythmia s imply that the needle has been advanced too far. Aspiration of a small amount of blood (eg 20 \200\22340mL) may improve cardiac output tempo rarily and \200\230buy time \200\231 to organize thoracotomy. \200 Pericardiocentesis is often unsuccessful due to clots which have formed in the pericardial sac and which cannot be aspirated. Perform immediate thoracotomy in the ED for cardiac arrest from penetrating trauma. Do not waste time on pericardiocentesis. Thoracotomy for cardiac tamponade Thoracotomy in the ED may be required in certain life-thr eatening emergencies, including cardiac arrest due to penetrating chest injury: the princip al aim is to decompress the pericardium and relieve tamponade. First exclude and treat othe r reversible causes of cardiac arrest (upper airway obstruction, b p.324; tension pneumotho rax, b p.328). Thoracotomy is not indicated for cardiac arrest following blunt injury. Procedure \200 Summon expert help (ED consultant; cardiothoracic, general or trauma surgeon; anesthetist) and proceed immediately. Do not wait. Whilst the thoracotomy tray is being opened, don gloves, a face shield and an apron, ensure that the patient is being ventilated with O 2 via a tracheal tube, and start external ches t compressions ( b p.49). Continue rapid IV infusion via multiple lines and obtain blood fo r transfusion. Standing on the patient \200\231s left side, abduct the left arm, stop chest com- pressions and open the left chest wall. Start the incision at the medial end of the 5th intercostal space and cut laterally just above the 6th rib into the axilla. Use a rib retractor to acce ss the thoracic cavity. If necessary, improve access further by continuing the incision med ially using strong scissors to cut through the sternum and into the right 5th intercostal s pace (clamshell thoracotomy). Speed is of the essence. \200 Identify the heart: carefully incise vertically through the bulging pericar- dium over its anterior surface, avoiding the left phrenic nerve. \200 Evacuate blood from the pericardial sac and identify the damage. \200 Place a \201 nger over the cardiac d efect and perform internal cardiac massage by compressing the heart between 2 \202 at han ds, with \201 ngers placed over defects. Close myocardial wounds using interrupted 4/0 pr olene sutures, using te \202 on or pericardial buttresses if necessary. Once sutures are i n place, stop internal cardiac massage and check cardiac rhythm and output. If the heart is \201 brillating, de \201 brillate using internal de \201 brillation paddles, by placin g a paddle over each side of the heart. Start with 5J energy initially, i as necessary to m ax of 50J. Use an external de \201 brillator if no internal paddles are available. Once a pulse has been restored, ensure that hypovolaemia is corrected. Give cefuroxime 1.5g IV, insert an arterial line and urinary catheter, recheck U&E, glucose, FBC, and clotting. The cardiothoracic surgeon will direct further surgical management. 344 CHAPTER 8 Major trauma