In the assessment and management of a pregnant woman involved in a motor vehicle crash, which ONE of the following is TRUE?
Answer: B: Fetal distress on CTG, which predicts underlying occult maternal placental bleeding, is characterised by:
The Kleihauer test needs at least 5 mL of fetomaternal haemorrhage for it to be positive. This means that the need for RhIg (or anti-D) should not be based on this test. Any Rh negative mother with significant trauma should be given anti-D within 72 hours from the injury. Neither anti-D immunoglobulin, nor tetanus toxoid is harmful to the fetus.
Serum HCO3 - is low in pregnant women because of the respiratory alkalosis caused by an increase in minute volume. The increased minute volume is due to an increased tidal volume by approximately 40%, whereas the respiratory rate usually remains normal. Low HCO3 - over and above this (<21 mmol/L) may suggest placental abruption or hypoperfusion.
References:
Regarding trauma in the third trimester of pregnancy, which ONE of the following is TRUE?
Answer: B: Trauma affects 7% of all pregnancies. The incidence increases with advancing gestational age. Just over half of trauma during pregnancy occurs in the third trimester. As the uterus enlarges, the diaphragm rises about an extra 4 cm. Subsequently, consideration should be given when placing an intercostal tube. It is recommended that the chest tube should be placed one or two spaces higher than the usual 5th intercostal space to allow for diaphragm elevation.
Clinical abdominal examination may be unreliable as the enlarged uterus displaces the abdominal content. The evaluation of possible injury to the abdomen is different because of the presence of the gravid uterus. In addition, stretching of the abdominal wall modifies the normal response to peritoneal irritation. Guarding and rebound can be blunted despite significant intraabdominal bleeding or organ injury, leading to an underestimation of the extent and gravity of maternal trauma.
The bladder is displaced into the abdominal cavity beyond 12 weeks’ gestation and is therefore more vulnerable to injury. The bladder becomes hyperaemic, like the uterus, and injury may lead to a marked increase in blood loss compared with a similar injury in a non-pregnant patient.
During pregnancy, the ligaments of the symphysis pubis and sacroiliac joints are loosened. A baseline diastasis of the pubic symphysis may exist and this can be mistaken for pelvic disruption on X-ray.
In a patient who has been injured in a bomb explosion once the immediate life threats have been excluded or attended to, assessment should be done to identify the injuries due to primary blast injury.
Regarding primary blast injury, which ONE of the following statements is TRUE?
Answer: B: Primary blast injury due to a bomb explosion is caused by the direct effects of pressure (barotrauma). The initial wave of high pressure caused by the bomb explosion is followed closely by the blast wind exposing the body organs to high and low pressure effects. If the patient is in a confined space such as a bus, the patient can be subjected to several reverberations and reflections of this pressure wave, hence a higher degree of primary blast injury is seen in such a patient.
The structures most commonly injured due to primary blast injury are air-filled structures (middle ear, lung and hollow viscera) and structures with air–fluid interfaces. Tympanic membrane rupture is most commonly seen followed by lung injury at second place. The colon is the most commonly affected visceral structure. Other important structures injured are the eyes and brain. Detection of a tympanic membrane rupture with otoscopy or evidence of middle or inner ear injury (deafness, tinnitus, vertigo) when the tympanic membrane is not visible is a sensitive marker of potential primary blast injury to other critical structures such as the lung. If there is no evidence of tympanic membrane rupture, primary blast injury to other organs is less likely. However, in a small number of patients primary blast injury to the lung and other organs can occur without tympanic membrane rupture. Primary blast injuries to the lung include alveolar disruption, pulmonary contusion, pneumothorax, pneumomediastinum, haemothorax, pulmonary oedema, parenchymal haemorrhage and systemic air embolism. These are the most common critical injuries in patients who were close to the blast centre. Abdominal solid organ injuries are usually due to secondary or tertiary injury.
Reference:
Regarding categories of injuries occurring in a bomb explosion, all of the following are correct EXCEPT:
Answer: D: Injuries occurring in a blast or a bomb explosion can be categorised into four categories according the mechanism of injury:
Which ONE of the following is applicable for estimating the total body surface area (TBSA) of a burn?
Answer: A: The total body surface area (TBSA) of burns can be estimated in a variety of ways. The ‘rule of nines’ is useful in adults and children >10 years of age. It should not be used for younger children because their head is larger and their extremities are smaller in proportion compared with adults. This rule divides the body into segments that are approximately 9% or multiples of nine and puts the percentages allocated for the head at 9%, the front of the trunk at 18%, the back of the trunk at 18%, the upper limbs at 9% and the lower limb at 18%, with the perineum forming the remaining 1%. The LundBrowder chart is useful for estimating the extent of burns in children. These charts are age adjusted and allows for changes in children at different ages. For instance, an infant’s head is approximately 18% of the TBSA, compared with 9% in an adult. Another way of working out the extent of the burn is to use the palm with the adducted fingers to calculate the extent of the burn as this will be approximately equivalent to 1% TBSA.
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