ATLS Primary Survey
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Direct answer
Airway with restriction of cervical spine motion comes first in the ATLS primary survey, which manages the multiply injured patient in a fixed sequence — Airway, Breathing, Circulation, Disability, Exposure — treating every life threat before moving on to the next. Current (10th edition) teaching puts catastrophic external haemorrhage at the very front ("C-ABC"), controlled by direct pressure or a tourniquet. The survey is never a one-time checklist: it is repeated from the top whenever the patient deteriorates, because deterioration in the resuscitation bay usually means a recurrent or missed life threat rather than a brand-new injury.
What you must remember
- Sequence is A (with cervical spine protection), B, C (with haemorrhage control), D, E; massive external bleeding is addressed before formal airway instrumentation.
- The lethal triad — hypothermia below 35 degrees C, metabolic acidosis, and coagulopathy — is what the primary survey is quietly trying to prevent.
- Tension pneumothorax: hypotension with unilateral absent breath sounds and distended neck veins; needle decompression at the fifth intercostal space, anterior axillary line, in adults per current ATLS (the older second space midclavicular site is still quoted in many Indian texts).
- ATLS shock classes: Class III is roughly 30–40% blood loss with tachycardia, tachypnoea, anxiety and a narrowed pulse pressure; blood pressure is notoriously maintained until about 30% loss.
- A Glasgow Coma Scale of 8 or less mandates a definitive airway, preferably by rapid sequence intubation with in-line manual cervical stabilisation.
- Adjuncts to the primary survey: chest and pelvic radiographs, eFAST, urinary and gastric catheters (only after the urethra is checked for injury).
- Resuscitate Class III/IV shock with blood products, not repeated crystalloid boluses, and accept permissive hypotension (systolic around 90 mmHg) — except in traumatic brain injury, where cerebral perfusion demands a higher target.
How to work through it
Take a 28-year-old motorcyclist brought in unconscious after a collision. First look for external bleeding — a torn femoral artery gets a tourniquet or direct pressure while someone else calls for blood. Then Airway: he is not speaking, so his airway is at risk; two people are needed, one stabilising the neck, the other performing rapid sequence intubation. Breathing: confirm tube placement with waveform capnography and equal chest rise; listen for symmetry. Circulation: two large-bore cannulae, blood sent for crossmatch, tranexamic acid considered within three hours of injury, and a pelvic binder applied before the pelvis is even imaged. An eFAST showing fluid in Morison's pouch in a hypotensive patient ends the radiology debate — that patient goes to theatre. Disability: GCS, pupil size and reactivity, lateralising signs. Exposure: full exposure with an active effort to keep him warm, then a log roll to inspect the back, a perineal inspection for blood at the meatus, and a digital rectal examination for tone and high-riding prostate.
The discipline lies in not being dragged forward: you do not examine a painful deformed femur while the airway is unprotected, and you do not order a CT scan in a patient whose blood pressure will not hold.
Where students slip
The commonest error in viva and in the bay is treating ABCDE as a linear checklist completed once. Examiners love the candidate who says "and I would return to A after every intervention." The second trap is the shock classification: candidates quote heart rate ranges from tables but forget that pulse pressure narrows before systolic pressure falls, which is precisely why Class II shock is missed. A third favourite: distinguishing tension pneumothorax from massive haemothorax — both give absent breath sounds and dullness or hyperresonance is the discriminator, along with neck veins (distended in tension, usually flat in massive haemorrhage). If the two cannot be separated in a crashing patient, a finger thoracostomy is both diagnostic and therapeutic.
Frequently asked questions
Which injuries are immediately life-threatening in the primary survey?
Airway obstruction, tension pneumothorax, open pneumothorax, massive haemothorax, cardiac tamponade, and catastrophic haemorrhage — each is treated as soon as it is found, before completing the rest of the survey.
Where does the needle go for tension pneumothorax decompression?
In adults, the fifth intercostal space in the anterior axillary line per current ATLS; the second intercostal space midclavicular line remains an accepted alternative and is the answer many older question banks expect.
What is the role of eFAST in the primary survey?
It is an adjunct to Circulation: free intraperitoneal fluid in a haemodynamically unstable blunt trauma patient indicates the need for laparotomy without further CT imaging.
Why is permissive hypotension avoided in head injury?
Because cerebral perfusion pressure equals mean arterial pressure minus intracranial pressure; allowing the blood pressure to run low in a brain-injured patient converts a survivable injury into secondary brain damage.
How much blood loss defines Class IV haemorrhage?
More than 40% of blood volume — lethargy, marked tachycardia, unobtainable narrow pulse pressure, and unrecordable systolic pressure; this is an immediate surgical emergency.