Nine Casualties, Two Ventilators, Four Units of O-Negative
A state transport bus overturns on a highway 14 km from a Community Health Centre. Nine casualties reach the CHC within 40 minutes. The CHC has two medical officers, three staff nurses, one functioning operating theatre, two ventilators and four units of O-negative packed cells. The nearest blood bank that can cross-match is 90 minutes away and the referral hospital is 2 hours by road. Six of the casualties are triaged on arrival. P1, a 34-year-old man, is walking and shouting, respiratory rate 22, radial pulse palpable, follows commands. P2, a 45-year-old woman, is unconscious, respiratory rate 36, capillary refill 3 seconds, weak thready pulse. P3, a 28-year-old man, has no spontaneous breathing even after chin lift and airway repositioning, and no palpable pulse. P4, a 60-year-old woman with an open femur fracture, is alert, respiratory rate 24, capillary refill 1 second, and cannot walk. P5, a 19-year-old woman, is confused, does not follow simple commands, respiratory rate 28, capillary refill 2 seconds. P6, a 50-year-old man is walking with a scalp laceration, respiratory rate 20, follows commands.
1. Assign a triage category to each of P1 to P6 using the START method, naming the specific physiological check that decides each category, and give the treatment order.
Read the worked answer
START uses three checks - respirations, perfusion (capillary refill), and ability to follow simple commands - plus whether the casualty is ambulatory.
- P1 - GREEN (minor). Walking, RR 22, normal perfusion, follows commands. He is the loudest person in the department; noise is not a triage criterion.
- P2 - RED (immediate). RR 36, i.e. over 30, so she is RED on the first check alone; 3-second capillary refill and unconsciousness confirm it.
- P3 - BLACK (deceased/expectant). No breathing after airway repositioning and no pulse. In a facility with two ventilators he must not consume staff time while P2 and P5 are alive and salvageable. Confirm and document, cover, and move on.
- P4 - YELLOW (delayed). Alert, RR 24, capillary refill 1 second, but cannot walk. The open femur fracture needs splinting, analgesia, tetanus cover and antibiotics - not the resuscitation bay.
- P5 - RED (immediate). She fails the mental-status check (does not follow commands), which is enough to make her immediate despite an acceptable respiratory rate of 28.
- P6 - GREEN (minor). Walking, RR 20, follows commands; scalp laceration to be cleaned and closed after the reds.
Treatment order: P2 → P5 → P4 → P1 and P6 together. P3 is not treated.
The reasoning that is actually being tested: P1 and P6 look dramatic and will demand attention; P5 looks quiet and will be overlooked. Triage must be driven by the checks, not by who is shouting or who arrived first.
2. Allocate the two ventilators and the four units of O-negative blood. Justify each allocation and state explicitly who receives nothing and why.
Read the worked answer
Ventilators (2).
- Ventilator 1 → P2. Unconscious with RR 36: she needs bag-mask ventilation immediately, then airway protection and mechanical support. This is not a discretionary call.
- Ventilator 2 → held in reserve, not automatically given to P5. P5's problem is an altered conscious level, not failure of ventilation; her rate of 28 is adequate. She needs an oropharyngeal airway, high-flow oxygen, cervical spine precautions, and reassessment every 15–30 minutes. Committing the last machine to her leaves nothing for a casualty who deteriorates in the next hour - P4 with fat embolism, or a delayed pneumothorax in P1.
- Written trigger for using ventilator 2: RR below 10 or above 30, SpO2 below 90% on high-flow oxygen, or a falling GCS. Document this so the decision is not re-argued at 3 a.m.
Blood (4 units O-negative, no cross-match for 90 minutes).
- P2: 2 units now. Unconscious, thready pulse, delayed capillary refill - presumed torso haemorrhage. She is the patient most likely to die in the next hour and most likely to be saved by blood.
- Hold 2 units. Do not give to P4 at this moment: she is compensating (capillary refill 1 second). Splint and traction the femur, which reduces ongoing blood loss, and reassess. If she becomes tachycardic with delayed refill, transfuse then.
- P1, P6: none. No indication; giving O-negative to a stable walking patient wastes an irreplaceable resource and creates a transfusion reaction risk for no benefit.
Do not give blood to P3.
3. P2 must be transferred to the referral hospital, 2 hours away. Draft the handover you would give by phone and state which decisions cannot wait for the receiving team.
Read the worked answer
SBAR handover.
- Situation: 45-year-old woman, unrestrained bus passenger, unconscious, GCS 6, RR 36, thready pulse, capillary refill 3 seconds, no external bleeding identified. Being ventilated and packaged now. ETA 2 hours plus.
- Background: No known comorbidities obtainable; no attendant identified yet. Two units O-negative running, two held in reserve here.
- Assessment: Presumed intra-abdominal or pelvic haemorrhage with airway compromise. Triage RED. Also P5, a 19-year-old with head injury and GCS deterioration, is being sent second.
- Recommendation: Request activation of the trauma team on arrival, a resuscitation bay with blood, and CT readiness. Confirm whether they will accept direct-to-theatre if she remains unstable.
Decisions that cannot wait for the receiving team: securing the airway and ventilating; starting uncrossmatched O-negative; splinting the femur; and applying cervical spine immobilisation to all casualties before movement. The receiving hospital can advise on destination within its building, but it cannot be allowed to authorise or veto the first 30 minutes of resuscitation from two hours away.
Also state the transport risk explicitly: if she arrests in transit, the crew must know in advance whether to continue or divert, and that should be agreed with the medical officer before the ambulance leaves the gate.