The values below are starting points, not aims in themselves. Almost all of them have proved to work better as ranges to stay within than as figures to strive for.
Ventilation
In ARDS: a tidal volume of 4–8 mL/kg ideal body weight, a plateau pressure ≤ 30 cmH₂O, a driving pressure ≤ 15 cmH₂O, prone positioning at a P/F ratio < 20 kPa (150 mmHg), and permissive hypercapnia as long as the pH stays above about 7.20.
Different targets apply when the intracranial pressure is raised: normocapnia (PaCO₂ 4.5–5.0 kPa) and avoidance of hypoxia, since hypercapnia raises the intracranial pressure.
Circulation
| Parameter | Target | Comment |
|---|---|---|
| MAP | ≥ 65 mmHg | 80–85 mmHg in chronic hypertension or when there are signs of inadequate perfusion |
| Urine output | > 0.5 mL/kg/h | |
| Lactate | Falling | A clearance > 10 % per 2 h is a reasonable target |
| ScvO₂ | 70–80 % | A low value suggests inadequate oxygen delivery |
| Capillary refill | < 3 s | Equivalent to lactate-guided resuscitation in septic shock |
| Haemoglobin, transfusion threshold | 70 g/L | 80 g/L in acute coronary syndrome |
See the circulatory and haemodynamic parameters for pressures, flows and shock profiles.
Acid–base and electrolytes in intensive care
Neurological monitoring
| Parameter | Target | Comment |
|---|---|---|
| Intracranial pressure (ICP) | < 22 mmHg | The treatment threshold in traumatic brain injury |
| Cerebral perfusion pressure (CPP) | 60–70 mmHg | CPP = MAP − ICP |
| RASS | −2 to 0 | Lightly sedated to awake and calm |
| CAM-ICU | Negative | Screen for delirium every shift |
| BIS (during neuromuscular blockade) | 40–60 |
Targeted light sedation with a daily wake-up trial shortens the time on the ventilator. See the article on confusion for the management of delirium in intensive care.
Renal replacement therapy
Absolute indications: refractory hyperkalaemia, refractory acidosis, refractory fluid overload, uraemic symptoms (pericarditis, encephalopathy) and certain poisonings. Early initiation without an absolute indication has not been shown to improve survival.
| Parameter | Guide value |
|---|---|
| Effluent dose, continuous therapy | 20–25 mL/kg/h |
| Net ultrafiltration | < 1.75 mL/kg/h |
Nutrition and prophylaxis
| Area | Guide value |
|---|---|
| Energy | 25 kcal/kg/day, reached gradually by day 3–4 |
| Protein | 1.2–2.0 g/kg/day |
| Enteral nutrition | Started within 48 h where possible |
| Thromboprophylaxis | Low-molecular-weight heparin unless contraindicated |
| Head of the bed | 30–45° |
| Stress ulcer prophylaxis | During mechanical ventilation, in coagulopathy, or with a history of gastrointestinal bleeding |
Refeeding syndrome
There is a risk in starvation, alcoholism, anorexia nervosa, or more than 5 days without nutrition. Check the phosphate, potassium and magnesium before and daily during the build-up, give thiamine before nutrition is started, and increase the energy intake slowly over the first few days. A falling phosphate is the earliest sign.
