Assessment and Management of the Critically Ill Patient

Core Concepts

The primary survey: ABCDE

The primary survey is a rapid, repeatable way to find and fix life threats in priority order:

• A — Airway: Is the airway open and protected? Listen for gurgling, stridor, or snoring; look for secretions, blood, or swelling; a patient who cannot speak or who makes abnormal airway sounds may need suction or an airway adjunct.
• B — Breathing: Is the patient moving air? Assess rate, depth, work of breathing, breath sounds, and oxygen saturation. A patient using accessory muscles, unable to finish a sentence, or desaturating is in respiratory trouble.
• C — Circulation: Is blood moving? Assess pulses (rate, quality, regularity), skin (color, temperature, moisture), capillary refill, blood pressure trend, and urine output. In early shock, the body compensates — heart rate and vascular tone rise before blood pressure falls.
• D — Disability: Is the brain getting what it needs? Assess level of consciousness (the most sensitive indicator of brain function), pupils, and movement. A drop in consciousness can mean hypoxia, poor perfusion, a metabolic problem, or a neurological event — and it is always reportable.
• E — Exposure: Fully examine the patient: temperature, skin integrity, wounds, drains, lines, and the rest of the body. Hidden injuries and early skin breakdown live here.

The primary survey is not done once — it is repeated continuously, and restarted from A whenever the patient's condition changes.

Physiologic monitoring

Critical care is monitor-rich, and each device answers a specific question:

• Pulse oximetry (SpO₂): estimates how well oxygen is loading onto hemoglobin. It is a proxy — it does not measure carbon dioxide or ventilation, and it can be unreliable with poor perfusion, motion, or certain conditions (such as carbon monoxide exposure).
• Cardiac (ECG) monitoring: tracks heart rate and rhythm continuously, catching dysrhythmias the moment they appear.
• Capnography (end-tidal CO₂): measures exhaled carbon dioxide — a window into ventilation and, for intubated patients, confirmation that the breathing tube is in the airway.
• Blood pressure: noninvasive cuffs cycle automatically; arterial lines provide continuous blood pressure for unstable patients.
• Urine output (via urinary catheter): a bedside proxy for organ perfusion — falling output is an early, quiet sign of trouble.

The key nursing skill is interpretation: devices produce data; nurses produce meaning. A single number means little; the trend over time, in context with the patient, is what drives action.

Early warning systems and rapid response

Because deterioration is announced in advance, hospitals build systems to catch the announcement. Early warning scores assign points to vital signs and consciousness; when the total crosses a threshold, staff are prompted to escalate. Rapid response teams — critical-care nurses, respiratory therapists, and clinicians who come to the bedside — bring intensive-care expertise to a deteriorating patient on a regular ward, often preventing a code or an ICU transfer. The exact scores, thresholds, and team compositions vary by institution; the principle is universal: escalate early, escalate formally, and never wait to see if things improve on their own.

The admission assessment and trends

On admission to critical care, the nurse performs a comprehensive head-to-toe assessment to establish the baseline: what is normal for this patient? From then on, focused reassessments track changes against that baseline. Documentation must capture both the finding and the trend ("RR 22, up from 16 two hours ago"), because trends are what make deterioration visible. Vital signs, consciousness, urine output, and pain are the core trackers in nearly every critically ill patient.

Interprofessional teamwork and structured communication

The ICU runs on a team: physicians, nurses, respiratory therapists, pharmacists, dietitians, chaplains, and social workers. With so many hands, communication is the highest-risk activity — which is why it is structured. SBAR (Situation, Background, Assessment, Recommendation) is the standard frame for reporting changes: state what is happening now, the relevant history, your assessment of the problem, and what you recommend. Bedside rounds and structured handoffs keep everyone — including the patient — on the same page. The nurse is often the patient's most continuous presence and advocate in these conversations.

Preventing complications of critical illness

Intensive care saves lives and creates new problems: immobility causes pressure injuries, weakness, and blood clots; mechanical ventilation and artificial airways invite pneumonia; sedation and sleep disruption cause delirium. Much of critical-care nursing is prevention:

• Skin: frequent repositioning, pressure-relief surfaces, and skin checks.
• Mobility: early mobility programs (getting patients up as soon as it is safe, per orders and protocols) reduce weakness and speed recovery.
• Oral care and head-of-bed elevation: standard elements of preventing ventilator-associated pneumonia (per institutional protocols).
• Sedation and sleep: minimizing sedation, protecting sleep cycles, and screening for delirium.
• Clot prevention: sequential compression devices, anticoagulation per orders, and early movement.

These are bundled into protocols that vary by facility; the nurse's job is to know the bundle and deliver it consistently.

Family presence and goals of care

Critical illness happens to families too. Family members need honest, plain-language updates, a designated contact person, and — depending on facility policy and patient wishes — the option to be present during rounds or resuscitation. When the outlook is poor, the nurse helps facilitate goals-of-care conversations: what matters to the patient, what treatments align with those values, and how the team should proceed. These are among the hardest and most important conversations in nursing, and supporting them is a nursing responsibility, not just a physician's task.

Common Confusions