A Focussed Assessment with Sonography for Trauma (FAST) scan is a point-of-care ultrasound examination conducted when a trauma patient arrives. Its primary purpose is to identify the presence of intra-abdominal free fluid, which is typically assumed to be haemoperitoneum in the context of trauma. This information helps healthcare providers make decisions regarding further management of the patient.

The sensitivity of FAST scanning for detecting intraperitoneal fluid is approximately 90%, while its specificity is around 95%. However, its sensitivity for detecting solid organ injuries is much lower. As a result, FAST scanning has largely replaced diagnostic peritoneal lavage as the preferred initial method for assessing haemoperitoneum.

During a standard FAST scan, four regions are assessed. The first is the subxiphoid transverse view, which is used to check for pericardial effusion and left lobe liver injuries. The second is the longitudinal view of the right upper quadrant, which helps identify right liver injuries, right kidney injuries, and fluid in the hepatorenal recess (Morison’s pouch). The third is the longitudinal view of the left upper quadrant, which is used to assess for splenic injury and left kidney injury. Lastly, the transverse and longitudinal views of the suprapubic region are examined to assess the bladder and fluid in the pouch of Douglas.

In addition to the standard FAST scan, an extended FAST or eFAST may also be performed. This involves examining the left and right thoracic regions to assess for the presence of pneumothorax and haemothorax.

The hepatorenal recess is the deepest part of the peritoneal cavity when a patient is lying flat. Therefore, it is the most likely area for fluid to accumulate in a supine position.

ATLS guidelines now suggest administering only 1 liter of crystalloid fluid during the initial assessment. If patients do not respond to the crystalloid, it is recommended to quickly transition to blood products. Studies have shown that infusing more than 1.5 liters of crystalloid fluid is associated with higher mortality rates in trauma cases. Therefore, it is advised to prioritize the early use of blood products and avoid large volumes of crystalloid fluid in trauma patients. In cases where it is necessary, massive transfusion should be considered, defined as the transfusion of more than 10 units of blood in 24 hours or more than 4 units of blood in one hour. For patients with evidence of Class III and IV hemorrhage, early resuscitation with blood and blood products in low ratios is recommended.

Based on the findings of significant trials, such as the CRASH-2 study, the use of tranexamic acid is now recommended within 3 hours. This involves administering a loading dose of 1 gram intravenously over 10 minutes, followed by an infusion of 1 gram over eight hours. In some regions, tranexamic acid is also being utilized in the prehospital setting.

The most recent ATLS guidelines recommend using either the jaw-thrust or chin-lift techniques as the initial approach to open the airway in trauma patients. It is important to avoid moving the head and neck in patients with suspected cervical spine injuries. However, if the patient is unconscious and does not have a gag reflex, temporarily placing an oropharyngeal airway can be beneficial.

To perform the chin-lift technique, gently place your fingers under the mandible and lift it upwards to bring the chin forward. Use your thumb to slightly depress the lower lip and open the mouth. Alternatively, you can place your thumb behind the lower incisors while gently lifting the chin. It is crucial not to hyperextend the neck during the chin-lift technique.

For the jaw thrust technique, place one hand on each side of the mandible and push it forward. This can be done in conjunction with a bag-mask device to achieve a good seal and provide adequate ventilation. Just like with the chin-lift technique, be cautious not to extend the patient’s neck.

A needle cricothyroidotomy is a procedure used in emergency situations to provide oxygenation when intubation and oxygenation are not possible. It is typically performed when a patient cannot be intubated or oxygenated. There are certain conditions that make this procedure contraindicated, such as local infection, distorted anatomy, previous failed attempts, and swelling or mass lesions.

To perform a needle cricothyroidotomy, the necessary equipment should be assembled and prepared. The patient should be positioned supine with their neck in a neutral position. The neck should be cleaned in a sterile manner using antiseptic swabs. If time allows, the area should be anesthetized locally. A 12 or 14 gauge over-the-needle catheter should be assembled to a 10 mL syringe.

The cricothyroid membrane, located between the thyroid and cricoid cartilage, should be identified anteriorly. The trachea should be stabilized with the thumb and forefinger of one hand. Using the other hand, the skin should be punctured in the midline with the needle over the cricothyroid membrane. The needle should be directed at a 45° angle caudally while negative pressure is applied to the syringe. Needle aspiration should be maintained as the needle is inserted through the lower half of the cricothyroid membrane, with air aspiration indicating entry into the tracheal lumen.

Once the needle is in place, the syringe and needle should be removed while the catheter is advanced to the hub. The oxygen catheter should be attached and the airway secured. It is important to be aware of possible complications, such as technique failure, cannula obstruction or dislodgement, injury to local structures, and surgical emphysema if high flow oxygen is administered through a malpositioned cannula.

This patient is showing significant signs of distress, including a highly elevated heart rate and respiratory rate, as well as very little urine output. Additionally, they are experiencing drowsiness, lethargy, and confusion. These symptoms indicate that the patient has suffered a class IV haemorrhage at this stage.

Recognizing the extent of blood loss based on vital signs and mental status abnormalities is a crucial skill. The Advanced Trauma Life Support (ATLS) classification for haemorrhagic shock correlates the amount of blood loss with expected physiological responses in a healthy 70 kg patient. In a 70 kg male patient, the total circulating blood volume is approximately five litres, accounting for around 7% of their total body weight.

The ATLS haemorrhagic shock classification is summarized as follows:

CLASS I
Blood loss (mL): Up to 750
Blood loss (% blood volume): Up to 15%
Pulse rate (bpm): <100
Systolic BP: Normal
Pulse pressure: Normal (or increased)
Respiratory rate: 14-20
Urine output (ml/hr): >30
CNS/mental status: Slightly anxious

CLASS II
Blood loss (mL): 750-1500
Blood loss (% blood volume): 15-30%
Pulse rate (bpm): 100-120
Systolic BP: Normal
Pulse pressure: Decreased
Respiratory rate: 20-30
Urine output (ml/hr): 20-30
CNS/mental status: Mildly anxious

CLASS III
Blood loss (mL): 1500-2000
Blood loss (% blood volume): 30-40%
Pulse rate (bpm): 120-140
Systolic BP: Decreased
Pulse pressure: Decreased
Respiratory rate: 30-40
Urine output (ml/hr): 5-15
CNS/mental status: Anxious, confused

CLASS IV
Blood loss (mL): >2000
Blood loss (% blood volume): >40%
Pulse rate (bpm): >140
Systolic BP: Decreased
Pulse pressure: Decreased
Respiratory rate: >40
Urine output (ml/hr): Negligible
CNS/mental status: Confused, lethargic

The effects of adrenaline on alpha-adrenergic receptors result in the narrowing of blood vessels throughout the body, leading to increased pressure in the coronary and cerebral arteries. On the other hand, the effects of adrenaline on beta-adrenergic receptors enhance the strength of the heart’s contractions and increase the heart rate, which can potentially improve blood flow to the coronary and cerebral arteries. However, it is important to note that these positive effects may be counteracted by the simultaneous increase in oxygen consumption by the heart, the occurrence of abnormal heart rhythms, reduced oxygen levels due to abnormal blood flow patterns, impaired small blood vessel function, and worsened heart function following a cardiac arrest.

A tension pneumothorax occurs when there is an air leak from the lung or chest wall that acts like a one-way valve. This causes air to build up in the pleural space without any way to escape. As a result, pressure in the pleural space increases and pushes the mediastinum into the opposite hemithorax. If left untreated, this can lead to cardiovascular instability, shock, and cardiac arrest.

The clinical features of tension pneumothorax include respiratory distress and cardiovascular instability. Tracheal deviation away from the side of the injury, unilateral absence of breath sounds on the affected side, and a hyper-resonant percussion note are also characteristic. Other signs include distended neck veins and cyanosis, which is a late sign. It’s important to note that both tension pneumothorax and massive haemothorax can cause decreased breath sounds on auscultation. However, percussion can help differentiate between the two conditions. Hyper-resonance suggests tension pneumothorax, while dullness suggests a massive haemothorax.

Tension pneumothorax is a clinical diagnosis and should not be delayed for radiological confirmation. Requesting a chest X-ray in this situation can delay treatment and put the patient at risk. Immediate decompression through needle thoracocentesis is the recommended treatment. Traditionally, a large-bore needle or cannula is inserted into the 2nd intercostal space in the midclavicular line of the affected hemithorax. However, studies on cadavers have shown better success in reaching the thoracic cavity when the 4th or 5th intercostal space in the midaxillary line is used in adult patients. ATLS now recommends this location for needle decompression in adults. The site for needle thoracocentesis in children remains the same, using the 2nd intercostal space in the midclavicular line. It’s important to remember that needle thoracocentesis is a temporary measure, and the insertion of a chest drain is the definitive treatment.

Based on the Lund and Browder chart, the total percentage of burns is calculated as 3 since it affects one side of both hands.

Further Reading:

Burn injuries can be classified based on their type (degree, partial thickness or full thickness), extent as a percentage of total body surface area (TBSA), and severity (minor, moderate, major/severe). Severe burns are defined as a >10% TBSA in a child and >15% TBSA in an adult.

When assessing a burn, it is important to consider airway injury, carbon monoxide poisoning, type of burn, extent of burn, special considerations, and fluid status. Special considerations may include head and neck burns, circumferential burns, thorax burns, electrical burns, hand burns, and burns to the genitalia.

Airway management is a priority in burn injuries. Inhalation of hot particles can cause damage to the respiratory epithelium and lead to airway compromise. Signs of inhalation injury include visible burns or erythema to the face, soot around the nostrils and mouth, burnt/singed nasal hairs, hoarse voice, wheeze or stridor, swollen tissues in the mouth or nostrils, and tachypnea and tachycardia. Supplemental oxygen should be provided, and endotracheal intubation may be necessary if there is airway obstruction or impending obstruction.

The initial management of a patient with burn injuries involves conserving body heat, covering burns with clean or sterile coverings, establishing IV access, providing pain relief, initiating fluid resuscitation, measuring urinary output with a catheter, maintaining nil by mouth status, closely monitoring vital signs and urine output, monitoring the airway, preparing for surgery if necessary, and administering medications.

Burns can be classified based on the depth of injury, ranging from simple erythema to full thickness burns that penetrate into subcutaneous tissue. The extent of a burn can be estimated using methods such as the rule of nines or the Lund and Browder chart, which takes into account age-specific body proportions.

Fluid management is crucial in burn injuries due to significant fluid losses. Evaporative fluid loss from burnt skin and increased permeability of blood vessels can lead to reduced intravascular volume and tissue perfusion. Fluid resuscitation should be aggressive in severe burns, while burns <15% in adults and <10% in children may not require immediate fluid resuscitation. The Parkland formula can be used to calculate the intravenous fluid requirements for someone with a significant burn injury.

The ATLS guidelines categorize chest injuries in trauma into two groups: life-threatening injuries that require immediate identification and treatment in the primary survey, and potentially life-threatening injuries that should be identified and treated in the secondary survey.

During the primary survey, the focus is on identifying and treating life-threatening thoracic injuries. These include airway obstruction, tracheobronchial tree injury, tension pneumothorax, open pneumothorax, massive haemothorax, and cardiac tamponade. Prompt recognition and intervention are crucial in order to prevent further deterioration and potential fatality.

In the secondary survey, attention is given to potentially life-threatening injuries that may not be immediately apparent. These include simple pneumothorax, haemothorax, flail chest, pulmonary contusion, blunt cardiac injury, traumatic aortic disruption, traumatic diaphragmatic injury, and blunt oesophageal rupture. These injuries may not pose an immediate threat to life, but they still require identification and appropriate management to prevent complications and ensure optimal patient outcomes.

By dividing chest injuries into these two categories and addressing them in a systematic manner, healthcare providers can effectively prioritize and manage trauma patients, ultimately improving their chances of survival and recovery.

If a polytrauma patient with a penetrating chest injury has an expanding cardiac tamponade that is left untreated, it can potentially lead to pulseless electrical activity.

Further Reading:

Cardiac tamponade, also known as pericardial tamponade, occurs when fluid accumulates in the pericardial sac and compresses the heart, leading to compromised blood flow. Classic clinical signs of cardiac tamponade include distended neck veins, hypotension, muffled heart sounds, and pulseless electrical activity (PEA). Diagnosis is typically done through a FAST scan or an echocardiogram.

Management of cardiac tamponade involves assessing for other injuries, administering IV fluids to reduce preload, performing pericardiocentesis (inserting a needle into the pericardial cavity to drain fluid), and potentially performing a thoracotomy. It is important to note that untreated expanding cardiac tamponade can progress to PEA cardiac arrest.

Pericardiocentesis can be done using the subxiphoid approach or by inserting a needle between the 5th and 6th intercostal spaces at the left sternal border. Echo guidance is the gold standard for pericardiocentesis, but it may not be available in a resuscitation situation. Complications of pericardiocentesis include ST elevation or ventricular ectopics, myocardial perforation, bleeding, pneumothorax, arrhythmia, acute pulmonary edema, and acute ventricular dilatation.

It is important to note that pericardiocentesis is typically used as a temporary measure until a thoracotomy can be performed. Recent articles published on the RCEM learning platform suggest that pericardiocentesis has a low success rate and may delay thoracotomy, so it is advised against unless there are no other options available.