Serial blood gas analyses and key management process
| Normal range | 0 h, arterial blood on room air | 2 h, arterial blood on room air | 4 h, arterial blood on NPO2 2 L·min−1 | 8 h, venous blood on room air | 24 h, venous blood on room air | |
| pH | 7.35–7.45 | 7.37 | 7.30 | 7.34 | 7.29 | 7.34 |
| PO2 | ||||||
| mmHg | 80.0–100.0 | 91.7 | 85.5 | 137.9 | 42.9 | 29.0 |
| kPa | 10.5–13.5 | 12.2 | 11.4 | 18.4 | 5.7 | 3.8 |
| PCO2 | ||||||
| mmHg | 35.0–45.0 | 31.5 | 20.0 | 27.3 | 42.7 | 39.0 |
| kPa | 4.5–6.0 | 4.2 | 2.6 | 3.6 | 5.7 | 5.2 |
| HCO3−, mmol·L−1 | 22.0–28.0 | 18.4 | 9.7 | 14.3 | 20.0 | 20.7 |
| BE, mEq·L−1 | −2.0–2.0 | −5.1 | −14.1 | −9.0 | −6.3 | −4.7 |
| Lactate, mmol·L−1 | 0.50–2.20 | 4.40 | 8.21 | 3.90 | 2.00 | 2.50 |
| Anion gap, mmol·L−1 | 4.0–12.0 | 18.1 | 26.8 | 22.2 | 16.5 | 10.8 |
| Plan of action | Nebulised salbutamol 5 mg Nebulised salbutamol 5 mg + ipratropium 0.25 mg Followed by MDI salbutamol 200 μg hourly ×6 Intravenous bolus 500 mL 0.9% saline | Intravenous ceftriaxone 2 g immediately and once daily Intravenous 2 L·day−1 HS+40 mL 8.4% NaHCO3 Off MDI salbutamol | Intravenous 2 L·day−1 0.9% saline Started on MART (budesonide/formoterol) | Off intravenous fluid |
NPO2: nasal prong oxygen; BE: base excess; HS: half saline; MART: maintenance and reliever therapy.