Advanced Blood Gas Analyzer
Systematic ABG diagnosis, Anion Gap, Delta Gap, and individualized weight-based clinical correction protocols.
Analyzer Parameters
Enter measured lab values & patient metrics.
Awaiting Blood Gas Values
Enter your patient's weight, measured blood gas, and electrolyte parameters in the form to calculate acid-base status, Anion Gap, Delta Gap, and individualized weight-based correction guidelines.
Clinical Context & Significance
Acid-base balance during cardiopulmonary bypass is critical for enzymatic function, vascular tone, and cellular respiration. This advanced analyzer integrates primary acid-base classification, Anion Gap, and Delta Gap analysis with personalized weight-based pharmacological and ventilatory correction protocols.
Anion Gap & Delta Gap
AG = Na⁺ - (Cl⁻ + HCO₃⁻). Normal AG is 8–12 mEq/L. Elevation indicates high anion gap metabolic acidosis (HAGMA), predominantly caused by lactic acidosis on CPB. Delta Gap (AG - 12 + HCO₃⁻) detects mixed disorders such as concurrent metabolic alkalosis or normal anion gap acidosis (NAGMA).
Weight-Based Interventions
Sodium bicarbonate dosage is calculated from extracellular fluid distribution (Dose = Weight × Base Deficit × 0.3 mEq). Sweep gas adjustments titrate CO₂ clearance proportionally (New Sweep = Current Sweep × [pCO₂ / 40]). Electrolyte protocols standardize K⁺ and Ca²⁺ replacement.
Clinical References: Rose BD, Post TW. Clinical Physiology of Acid-Base and Electrolyte Disorders. 5th ed. | Gravlee GP, et al. Cardiopulmonary Bypass: Principles and Practice.
Advanced Acid-Base Physiology, Gap Analysis & Weight-Based Interventions
Physiological Principles & Clinical Context
Simple blood gas analysis may fail to identify complex, mixed metabolic acid-base disorders commonly seen in critically ill patients, shock states, or long CPB runs. Advanced ABG analysis utilizes the Anion Gap (AG) to classify metabolic acidosis based on unmeasured anions (e.g., lactate, ketoacids, phosphate). Calculating the Delta Gap determines if a high anion gap acidosis is accompanied by secondary metabolic alkalosis or non-anion gap metabolic acidosis (NAGMA). Furthermore, integrating the patient's weight allows quantitative dosing of sodium bicarbonate and proportional titration of sweep gas flow for precise acid-base restoration.
Clinical Targets & Safe Ranges
- •Normal Serum Sodium (Na⁺): 135 to 145 mEq/L
- •Normal Serum Chloride (Cl⁻): 95 to 105 mEq/L
- •Normal Anion Gap Range (without Potassium): 8 to 12 mEq/L (Rises during anaerobic metabolism/lactic acidosis).
- •Delta Ratio interpretation: < 0.4 indicates NAGMA; 0.4 to 1.0 indicates mixed NAGMA and HAGMA; 1.0 to 2.0 indicates pure HAGMA; > 2.0 indicates concurrent Metabolic Alkalosis.
- •Base Deficit Bicarbonate Threshold: Administer 50% of the calculated weight-based deficit slowly to avoid hyperosmolality, sudden hypokalemia, or paradoxical intracellular CO₂ accumulation.
Mathematical Formulation
- ƒAnion Gap Formula: Anion Gap = [Na⁺] - ( [Cl⁻] + [HCO₃⁻] )
- ƒDelta Gap Formula: Delta Gap = (Anion Gap - 12) + [HCO₃⁻]
- ƒDelta Ratio: Delta Ratio = (Anion Gap - 12) / (24 - [HCO₃⁻])
- ƒSodium Bicarbonate Dosing: NaHCO₃ (mEq) = Weight (kg) × Base Deficit × 0.3
- ƒSweep Gas Titration: Target Sweep (L/min) = Current Sweep (L/min) × (Current pCO₂ / Target pCO₂)
Academic & Clinical References
- Rose BD, Post TW. Clinical Physiology of Acid-Base and Electrolyte Disorders. 5th ed. New York: McGraw-Hill; 2001.
- Siggaard-Andersen O. The Acid-Base Status of the Blood. Copenhagen: Munksgaard; 1974.
- DuBose TD Jr. Acid-base disorders. In: Skorecki K, Chertow GM, Marsden PA, et al., eds. Brenner and Rector's The Kidney. 10th ed. Philadelphia: Elsevier; 2016:chap 16.