Neurological Assessment

A rapid neurological assessment should be performed on every ICU admission. This includes the Glasgow Coma Scale (GCS) — documented as E, V, and M scores individually, not just as the total — pupil size and reactivity bilaterally, and a screen for focal neurological deficits. In intubated and sedated patients, the motor component of the GCS and pupillary responses are the most useful ongoing assessments.

Sedation and Analgesia

The goals of sedation and analgesia in the ICU have evolved significantly over the past two decades. Historically, patients were deeply sedated routinely; evidence now strongly supports a strategy of light sedation (targeting RASS -1 to 0 in most patients), with analgesia-first approaches (pain is treated before adding sedatives), and daily sedation holds to assess neurological status and facilitate weaning from mechanical ventilation.

The Richmond Agitation-Sedation Scale (RASS) is the most widely used validated tool for assessing sedation depth. The Pain, Agitation, and Delirium (PAD) guidelines from the Society of Critical Care Medicine recommend targeting a RASS of -1 to 0 (lightly sedated or alert) in most mechanically ventilated patients unless there is a specific indication for deeper sedation (e.g. severe ARDS requiring prone positioning, status epilepticus, or raised ICP requiring burst suppression).

Blood Glucose

Stress hyperglycaemia is almost universal in critical illness, driven by cortisol, catecholamines, and inflammatory cytokines that promote gluconeogenesis and impair insulin-mediated glucose uptake. Both hyperglycaemia and hypoglycaemia are harmful in critically ill patients. The NICE-SUGAR trial definitively demonstrated that tight glucose control (targeting 4.5–6.0 mmol/L) increased mortality compared to conventional control (targeting 6–10 mmol/L), primarily due to episodes of severe hypoglycaemia. The recommended target in all critically ill patients is therefore 6–10 mmol/L, achieved with an insulin infusion if dietary management alone is insufficient.