Sodium Bicarbonate

# sodium bicarbonate ## Overview - **Classification**: Electrolyte, Systemic Alkalinizer - **Mechanism**: Increases plasma bicarbonate, buffering excess hydrogen ions (H+), thereby raising blood pH and reversing metabolic acidosis. ## Primary Indications 1. **Metabolic Acidosis** - Correction of severe metabolic acidosis (pH <7.1) due to various causes (e.g., DKA, renal failure, lactic acidosis). 2. **Urine Alkalinization** - To enhance excretion of acidic drugs (e.g., salicylates, phenobarbital) or prevent kidney stone formation. 3. **Specific Drug Overdoses** - Treatment of cardiotoxicity in certain drug overdoses (e.g., tricyclic antidepressants). 4. **Cardiac Arrest** - For pre-existing metabolic acidosis or prolonged arrests unresponsive to other therapies (controversial, not routine). ## Adult Dosing ### Standard Dosing **Severe Metabolic Acidosis (e.g., pH <7.1)** - **Dose**: **0.5-1 mEq/kg** - **Frequency**: Administer over **1-2 hours** initially. Subsequent doses guided by ABGs. - **Route**: Intravenous (IV) infusion - **Special Considerations**: Calculate deficit to guide total dose: Bicarb deficit (mEq) = 0.5 x Body Weight (kg) x (24 - serum HCO3). Administer half of deficit over 3-4 hours, then reassess. **Urine Alkalinization / Specific Drug Overdoses (e.g., Salicylate Toxicity)** - **Dose**: **1-2 mEq/kg** (initial bolus) - **Frequency**: Followed by infusion of **150 mEq** in 1 L D5W at **100-200 mL/hr** - **Route**: Intravenous (IV) infusion - **Target**: Maintain urine pH >7.5 and serum pH <7.55. **Cardiac Arrest (Refractory/Prolonged)** - **Dose**: **1 mEq/kg** - **Frequency**: Single dose, may repeat after 10-15 min if indicated. - **Route**: Intravenous (IV) push - **Special Considerations**: Only for documented acidosis, hyperkalemia, or specific overdoses. Not recommended for routine cardiac arrest. ### Dose Adjustments - **Renal Impairment**: Use with extreme caution. Monitor electrolytes (Na, K), fluid status, and acid-base balance closely due to risk of fluid overload and electrolyte abnormalities. - **Hepatic Impairment**: No specific dose adjustment. Underlying cause of acidosis should be addressed. - **Elderly Patients**: Use with caution. Start at lower end of dosing range due to increased risk of fluid overload, hypernatremia, and electrolyte imbalances. Monitor closely. ## Pediatric Dosing ### Neonates (0-28 days) - **Dose**: **1-2 mEq/kg** - **Frequency**: Administer over **30-60 minutes** (extremely slow infusion). - **Maximum**: **8 mEq/kg/day** - **Special Notes**: Must be diluted to **0.5 mEq/mL** or less to reduce risk of hyperosmolality and intraventricular hemorrhage. Administer via central line if possible. ### Infants (1-12 months) - **Dose**: **1-2 mEq/kg** - **Frequency**: Administer over **15-30 minutes**. - **Maximum**: **8 mEq/kg/day** - **Special Notes**: Dilute to **0.5 mEq/mL** or less. Monitor for fluid overload and electrolyte shifts. ### Children (1-12 years) - **Dose**: **1-2 mEq/kg** - **Frequency**: Administer over **15-30 minutes**. - **Maximum**: **8 mEq/kg/day** or **adult dose** (whichever is lower). - **Special Notes**: Dilution to **0.5 mEq/mL** is recommended. ### Adolescents (13-18 years) - **Dose**: Generally follow **adult dosing guidelines**. - **Maximum**: Refer to adult maximum doses. - **Special Notes**: Consider weight-based dosing for smaller adolescents to avoid overdose. ## Safety Information ### Contraindications - **Absolute**: Metabolic alkalosis - **Absolute**: Hypocalcemia (untreated) - **Absolute**: Hypernatremia - **Absolute**: Chloride loss from vomiting or suction - **Relative**: Pulmonary edema (due to sodium load) ### Common Adverse Effects - **Very Common (>10%)**: Metabolic alkalosis, hypernatremia, fluid overload - **Common (1-10%)**: Hypokalemia, hypocalcemia (may precipitate tetany), increased CO2 production - **Serious but Rare**: Intracranial hemorrhage (especially in neonates), extravasation necrosis, electrolyte disturbances worsening arrhythmias. ### Key Drug Interactions - **Acidic Drugs (e.g., salicylates, methotrexate)**: Enhances renal elimination by increasing urine pH. Monitor drug levels. - **Alkaline Drugs (e.g., quinidine, amphetamines, ephedrine)**: Decreases renal elimination by increasing urine pH. Increased toxicity risk. - **Calcium-containing solutions**: **Physical incompatibility**, forms precipitate. **DO NOT co-administer**. - **Lithium**: Increased renal clearance of lithium, potentially reducing efficacy. Monitor lithium levels. - **Diuretics (e.g., furosemide, thiazides)**: May worsen electrolyte imbalances (e.g., hypokalemia). ## Monitoring & Follow-up - **Before Treatment**: Baseline Arterial Blood Gas (ABG), serum electrolytes (Na, K, Cl, HCO3), renal function (BUN/Cr). - **During Treatment**: Repeat ABG and serum electrolytes every **1-2 hours** initially, then less frequently based on clinical status. Monitor fluid balance, urine output, and respiratory status closely. - **Clinical Signs**: Watch for signs of fluid overload (rales, peripheral edema), tetany (due to hypocalcemia), muscle weakness (hypokalemia), and altered mental status. ## Clinical Pearls - 💡 **Slow Administration**: Administer slowly, especially in neonates and children, to minimize risk of hyperosmolality, hypernatremia, and intracranial hemorrhage. - 💡 **Dilution is Key**: For pediatric patients and often in adults, dilute to **0.5 mEq/mL** or less to reduce osmolality and vein irritation. - 💡 **Incompatible**: **NEVER mix with calcium-containing solutions** or infuse through the same line due to precipitation risk. - 💡 **Underlying Cause**: Address and treat the underlying cause of acidosis, as sodium bicarbonate is symptomatic therapy. - 💡 **Cardiac Arrest Use**: Reserve for specific situations in cardiac arrest; routine use is not recommended and may be harmful. > **⚠️ Important**: This information is for educational purposes only. Always consult current prescribing information, local guidelines, and clinical judgment before prescribing.