CHAPTER 54: Airway Management of the Pregnant Trauma Victim

CASE PRESENTATION

A 35-year-old pregnant woman, approximately 36 weeks gestation, is admitted to the emergency department (ED) following a motor vehicle crash. She has a closed head injury, bilateral femoral fractures, and possible abdominal trauma. Her Glasgow Coma Score (GCS) is 5: she does not open her eyes (1); there is no audible vocalization (1); and she is showing decorticate rigidity (3). Her heart rate is 135 beats per minute, blood pressure 85/40 mm Hg, and respiratory rate is 40 breaths per minute and shallow. Fetal heart rate (FHR) is 110 beats per minute. The oxygen saturation (SaO₂) is 90%, on a non-rebreathing oxygen mask. A cervical collar is in place and Thomas splints are being applied to both legs.

INITIAL ASSESSMENT OF THE PATIENT

What Are the Immediate Evaluation and Management Priorities in This Patient?

Initial evaluation and management priorities for the near-term parturient are no different than any trauma victim—assessment of airway, breathing and circulation (ABCs), followed by a secondary survey, including assessment of the abdomen and fetus.

Unique considerations related to the pregnancy, such as supine hypotensive syndrome and the significant capillary engorgement of the nasal and oropharyngeal mucosa, may impact positioning, hemodynamics, and airway management.¹

Immediate attention is directed toward the airway. Her GCS and oxygen saturations mandate endotracheal intubation and ventilation. She is not a crash airway, and therefore an evaluation for difficulty is performed employing the MOANS, LEMON, CRANE, RODS, and SHORT mnemonics (see sections “Difficult BMV: MOANS,” “Difficult DL Intubation: LEMON,” “Difficult VL Intubation: CRANE,” “Difficult Use of an EGD: RODS,” and “Difficult Cricothyrotomy: SHORT” in Chapter 1). In this particular patient, difficulty should be anticipated and an approach as suggested in the Difficult Airway Algorithm (Chapter 2) adopted, recognizing that parturients at term have a substantially elevated risk of aspiration, particularly in this circumstance where protective airway reflexes are compromised, and the patient is not responding to command.

Following airway management, attention is directed to an assessment of breathing. Her lung fields must be evaluated for presence, equality, and quality of breath sounds. This evaluation, coupled with a stat portable chest x-ray, may uncover a pneumothorax and/or hemothorax that may require treatment.

In pregnancy, minute ventilation is normally increased by approximately 45%, largely through an increase in tidal volume. This increased minute ventilation results in a fall in PaCO₂ to approximately 30 mm Hg. Therefore, one should initially moderately and empirically hyperventilate this patient. Ventilation may be guided by arterial blood gases once resuscitation has been established.

During pregnancy, an increase in gastric acid production results not only in an increased volume but a decrease in the pH. Coupled with a decrease in the competency of the lower esophageal sphincter, a greatly enhanced risk of reflux is present. The ...