Table 3.
Acid–base characteristics of cerebrospinal fluid of the SAH population
| Variables | Nonhypocapnic alkalosis (n = 12) | Hypocapnic alkalosis (n = 8) | p value |
|---|---|---|---|
| pH | 7.36 ± 0.05 | 7.33 ± 0.06 | 0.26 |
| PCO2 (mm Hg) | 41 ± 4 | 39 ± 4 | 0.47 |
| ATOT (mmol/L) | 1.3 ± 0.5 | 1.1 ± 0.3 | 0.18 |
| SID (mmol/L) | 24.2 ± 1.7 | 21.3 ± 1.9 | 0.002 |
| Na+ (mmol/L) | 143 ± 5 | 143 ± 1 | 0.98 |
| K+ (mmol/L) | 2.5 ± 0.4 | 2.6 ± 0.7 | 0.78 |
| Ca2+ (mmol/L) | 1.00 ± 0.04 | 0.96 ± 0.07 | 0.11 |
| Mg2+ (mmol/L) | 1.17 ± 0.07 | 1.13 ± 0.04 | 0.15 |
| Cl− (mmol/L) | 122 ± 5 | 125 ± 3 | 0.13 |
| Lac− (mmol/L) | 3.4 ± 1.4 | 3.1 ± 1.2 | 0.60 |
| HCO3− (mmol/L) | 22.7 ± 2.1 | 20.4 ± 2.3 | 0.03 |
| Phosph− (mEq/L) | 0.68 ± 0.23 | 0.62 ± 0.17 | 0.56 |
| Alb− (mEq/L) | 0.37 ± 0.26 | 0.19 ± 0.12 | 0.09 |
| Osmolarity (mOsm/L) | 290 ± 9 | 290 ± 2 | 0.95 |
| Gluc (mg/dL) | 73 ± 15 | 76 ± 14 | 0.72 |
| Hb (g/dL) | 0.4 ± 0.4 | 0.3 ± 0.3 | 0.70 |
| RBC (× 106/µL) | 0.12 ± 0.14 | 0.09 ± 0.07 | 0.59 |
| WBC (cells/µL) | 326 ± 572 | 408 ± 588 | 0.76 |
| ΔSID (mmol/L) | 14.4 ± 3.7 | 13.8 ± 1.2 | 0.65 |
| ΔPCO2 (mm Hg) | 0.4 ± 3.8 | 7.8 ± 3.7 | < 0.001 |
Data are expressed as mean ± standard deviation
Alb−, ionized albumin concentration, ATOT, total amount of weak noncarbonic acids, Ca2+, ionized calcium concentration, Cl−, chloride concentration, Gluc, glucose concentration, Hb, hemoglobin concentration, HCO3−, bicarbonate concentration, K+, potassium concentration, Mg2+, magnesium concentration, Na+, sodium concentration, PCO2, partial pressure of carbon dioxide, Phosph−, ionized phosphate concentration, RBC, red blood cell count, SAH, aneurismal subarachnoid hemorrhage, SID, strong ion difference, WBC, white blood cell count