Bedside Snapshot

Use It For
TCA or other sodium-channel blocker cardiotoxicity (wide QRS, dysrhythmia, hypotension); hyperkalemic cardiac arrest; salicylate poisoning; severe ICU metabolic acidemia (pH ≤7.20) in selected patients
Adult Dose
  • Sodium-channel blocker: 50–150 mEq IV/IO bolus of 8.4%, repeat to QRS narrowing (ceiling pH 7.55)
  • Hyperkalemic arrest: 50 mEq IV/IO, repeat every 5–10 min per blood gas
  • Salicylate: 1–2 mEq/kg, then 150 mEq/L drip
Pediatric Dose
1 mEq/kg IV/IO slowly (max 50 mEq/dose) for hyperkalemia or sodium-channel blocker toxicity; TCA 1–3 mEq/kg. Under 2 yr: slowly, max 8 mEq/kg/day. Not for newborn resuscitation
Onset / Duration
IV: immediate buffering / variable (renal excretion); the pH rise depends on ventilation clearing the CO₂
Do Not Give / Hold If
Routine cardiac arrest; chloride loss from vomiting or GI suction; diuretic hypochloremic alkalosis; pH above 7.55; ventilation inadequate; same line as calcium; ET route
Watch For
Hypernatremia and volume overload (Na⁺, lungs); hypokalemia (K⁺, U waves); low ionized Ca²⁺ and tetany; extravasation necrosis (IV site)
Reversal / Rescue
No antidote: stop bicarbonate; 0.9% NaCl and KCl for alkalosis with low K⁺; calcium gluconate for tetany; extravasation: elevate, warmth, local lidocaine or hyaluronidase
Must Remember
Not for routine cardiac arrest. Give it for a reason (sodium-channel blocker, hyperkalemia, salicylate) and ventilate to clear the CO₂ it makes. 8.4% is 1 mEq/mL; 4.2% is 0.5 mEq/mL.

Indications

Emergency & Prehospital

  • Tricyclic antidepressant (TCA) poisoning with life-threatening cardiotoxicity: QRS widening, ventricular dysrhythmia or hypotension; first-line antidote (AHA 2025 Part 10, COR 1, B-NR)
  • Other sodium-channel blocker cardiotoxicity: class Ia/Ic antiarrhythmics, diphenhydramine, cocaine wide-complex tachycardia or arrest (adults COR 2a, C-LD; children COR 2a, C-EO), local anesthetic systemic toxicity (LAST) with life-threatening wide-complex tachycardia as an adjunct (COR 2a, C-EO); reasonable to use, based on case reports (AHA 2025 Part 10, rec 5, COR 2a, C-EO), with a response less predictable than with TCAs, and uncertain efficacy with bupropion, propranolol and taxine-containing plants. In LAST, 20% intravenous lipid emulsion is first-line (AHA 2025 Part 10, COR 1, C-LD)
  • Hyperkalemic cardiac arrest: known or suspected hyperkalemia as the cause, given alongside calcium (see calcium chloride). AHA 2025 Part 10 says the effectiveness of IV sodium bicarbonate in suspected hyperkalemic arrest is not well established (COR 2b, C-EO). UKKA 2026 suggests it (2C). The evidence is weak and the guidelines disagree, so follow local protocol.
  • Pediatric cardiac arrest with a specific cause: hyperkalemia or sodium-channel blocker toxicity only (AHA 2025 Part 8, rec 5: routine use COR 3, No Benefit)

ED / ICU / Transport

  • Salicylate poisoning: serum and urine alkalinization. The aim is to pull salicylate out of tissues and speed renal excretion, while you assess for hemodialysis (see hemodialysis)
  • Severe metabolic acidemia in the ICU (pH ≤7.20 with PaCO₂ ≤45 mmHg and HCO₃⁻ ≤20 mmol/L): selected patients, to reduce the need for kidney replacement therapy
  • Diabetic ketoacidosis (DKA): not routine. Adults: consider only at pH <7.0 per the ADA 2024 consensus. Children: avoid unless hyperkalemia is life-threatening or venous pH is <6.9 with impaired cardiac contractility per the ISPAD 2022 guideline. Bicarbonate is linked to cerebral injury. Specialist use only. No dose is shown (see Dosing).
  • Metabolic acidosis from bicarbonate loss: severe diarrhea with significant bicarbonate loss (labeled)
  • Hyperkalemia without arrest: not routine; an adjunct only, usually with severe metabolic acidosis

Other Uses

  • Other labeled uses: barbiturate and methanol poisoning; hemolytic transfusion reactions that need urine alkalinization
  • Chronic metabolic acidosis in chronic kidney disease (CKD): oral sodium bicarbonate to prevent clinically significant acidosis (UKKA 2026 recommends it for serum bicarbonate below 22 mmol/L); outpatient
Not for routine cardiac arrest: Arrest is not an indication. AHA 2025 Part 9 does not recommend routine sodium bicarbonate in adult cardiac arrest (COR 3: No Benefit, B-R). A specific cause is the indication, such as sodium-channel blocker toxicity or hyperkalemia. Give it for that and only that.

Dosing & Administration

Doses vary by protocol; follow local protocols and medical direction.

Available Forms

  • 8.4% (1 mEq/mL): 50 mL (50 mEq) prefilled syringe or single-dose vial; also 10 mL (10 mEq) vials. The adult crash-cart form, carried by EMS and EDs. About 2 mOsm/mL (calculated; most labels list 2 mOsmol/mL, the Hospira label 1.56). It is strongly hypertonic.
  • 7.5% (0.9 mEq/mL): 50 mL syringe containing 44.6 mEq. Check the label: a "50 mL amp" is not always 50 mEq.
  • 4.2% (0.5 mEq/mL): 5 mL (2.5 mEq) vials and 10 mL (5 mEq) syringes or vials; label osmolarity 0.84 mOsm/mL.
  • Isotonic infusion (150 mEq/L): pharmacy-mixed as 150 mEq NaHCO₃ in 1 L D5W, or a commercial premixed 1.26% (150 mEq in 1,000 mL) bag. For infusions only. Never use it for arrest boluses. The premixed-bag label limits it to settings that do not need rapid administration (not cardiac arrest). The label doses it at 2–5 mEq/kg over 4–8 hr (age 2 yr and older), or 1–2 mEq/kg over 4–8 hr with no bolus (under 2 yr, including neonates). The volume is large for small children, so the label suggests a more concentrated product.
  • Oral tablets: chronic acidosis in CKD; not used in emergencies.

Adult Dosing

IndicationDose & RouteRepeat / MaxNotes
TCA or other sodium-channel blocker cardiotoxicity
50–150 mEq IV/IO bolus of 8.4% (AHA 2025 Part 10, Table 4)
Repeat for persistent QRS widening, dysrhythmia or hypotension; endpoint pH about 7.50 or resolved hypotension and QRS prolongation (debated); ceilings pH 7.55 and Na⁺ 155 mEq/L
Treat life-threatening cardiotoxicity (AHA 2025 Part 10, rec 1). In Boehnert and Lovejoy (1985), seizures occurred at a QRS of 100 ms or longer and ventricular arrhythmias at 160 ms or longer (see References). Hyperventilation with bicarbonate is reasonable in ventilated patients (AHA 2025 Part 10, rec 3, COR 2a, C-LD). If intubated, adjust minute ventilation to control pH; if more sodium is needed once pH is at its 7.55 ceiling, hypertonic saline raises Na⁺ separately. Check a blood gas after every few boluses.
Sodium-channel blocker: maintenance infusion
150 mEq/L (150 mEq NaHCO₃ in 1 L D5W) IV infusion at 1–3 mL/kg/hr (weight-based)
Titrate to QRS and pH about 7.50; do not exceed pH 7.55; continue until the ECG normalizes (published regimens 24–48 hr)
Infusion versus repeat boluses as needed is unsettled. Hypokalemia is the most expected complication: check K⁺ often and replace it alongside. Involve a toxicologist or poison center.
Hyperkalemic cardiac arrest
50 mEq (50 mL of 8.4%) IV/IO push
May repeat 50 mEq every 5–10 min, guided by blood gas (label arrest dosing)
AHA 2025 Part 10: effectiveness of IV sodium bicarbonate in suspected hyperkalemic arrest not well established (COR 2b, C-EO); UKKA 2026 suggests it (2C). Evidence is weak and guidelines differ; follow local protocol. If used, give with the rest of the hyperkalemia bundle and flush the line between calcium and bicarbonate. The label allows one to two 50 mL vials (44.6–100 mEq) initially, so 50 mEq is the lower end.
Hyperkalemia without arrest
Not routine. Consider only with severe metabolic acidosis (pH <7.2) or when IV calcium is contraindicated
Protocol-dependent: some critical-care protocols give 100–250 mL of 8.4% (100–250 mEq), with a sodium and fluid-load risk
Bicarbonate alone does not lower K⁺ acutely. Stabilize with calcium, shift with insulin-glucose and albuterol, remove with binders or dialysis. The 2025 ILCOR systematic review found no effect of bicarbonate on K⁺ (very low certainty).
Salicylate poisoning
1–2 mEq/kg IV bolus of 8.4%, then 150 mEq NaHCO₃ in 1 L D5W at 2–3 mL/kg/hr
Extra boluses if severe; target serum pH 7.50–7.55 and urine pH >7.5; do not exceed serum pH 7.55
Start for pH below 7.4, acute level above 30 mg/dL or significant symptoms (expert practice; not a sourced threshold). Add 40–60 mEq KCl to each liter and keep K⁺ normal, or the urine will not alkalinize. Doses are expert practice: a 2025 narrative review found no study supporting specific dosing.
Salicylate: before intubation
2 mEq/kg IV bolus 5–10 min before induction
Single pre-induction bolus; then match the pre-intubation minute ventilation
Expert practice, no trial data. Avoid intubation if possible; minimize apnea time.
Severe metabolic acidemia, ICU (pH ≤7.20)
4.2% IV infusion titrated to arterial pH ≥7.30
Titrate to pH ≥7.30; trial patients needed a median 500 mL (250 mEq), IQR 375–1,000 mL
BICAR-ICU and BICAR-ICU2 protocol, which enrolled only metabolic acidemia (PaCO₂ ≤45 mmHg, HCO₃⁻ ≤20 mmol/L, SOFA ≥4 or lactate ≥2 mmol/L) and excluded respiratory acidemia, GI or urinary bicarbonate loss, DKA, toxic ingestions and end-stage kidney disease. Ensure ventilation can clear the extra CO₂. Watch Na⁺ and ionized Ca²⁺.
Less urgent metabolic acidosis
2–5 mEq/kg IV over 4–8 hr
Stepwise; do not fully correct in the first 24 hr (aim for total CO₂ about 20 mEq/L at the end of day 1)
Treat the cause first: insulin and fluids in DKA, volume in shock. DKA: specialist use only. Adults: consider only at pH <7.0 per the ADA 2024 consensus. Children: avoid unless hyperkalemia is life-threatening or venous pH is <6.9 with impaired cardiac contractility per the ISPAD 2022 guideline; linked to cerebral injury. No dose is shown here.
Undifferentiated cardiac arrest
Not recommended routinely
Do not give routinely (AHA 2025 Part 9: COR 3, No Benefit)
The label arrest dose (44.6–100 mEq, then 44.6–50 mEq every 5–10 min) applies only when a specific indication exists. AHA 2025 Part 9, rec 5: COR 3, No Benefit, B-R.

Pediatric Dosing

IndicationDose (per kg) & RouteMax Single / Max TotalNotes
Cardiac arrest or instability from hyperkalemia or sodium-channel blocker toxicity
1 mEq/kg IV/IO slowly (1 mL/kg of 8.4%), after adequate ventilation
Max 50 mEq/dose (adult dose); repeat only for the same indication, guided by blood gas
Not for routine pediatric arrest (AHA 2025 Part 8, rec 5: COR 3, No Benefit). Never give by endotracheal (ET) tube.
TCA cardiotoxicity
1–3 mEq/kg IV/IO bolus (AHA 2025 Part 10, Table 4; NASEMSO v3.0 gives 1–2 mEq/kg), then 150 mEq/L in D5W infusion at 1–3 mL/kg/hr
Never more than the adult dose (50–150 mEq); stop boluses at serum pH 7.55
Same QRS, pH and Na⁺ (155 mEq/L) endpoints as adults; COR 2a, C-LD. Monitor and replace K⁺.
Salicylate poisoning
1–2 mEq/kg IV bolus, then 150 mEq/L in D5W at 2–3 mL/kg/hr
Adult maximums; serum pH no higher than 7.55
Weight-based regimen; expert practice, as in adults (pediatric-specific data are limited): involve a toxicologist. Keep K⁺ normal.
Less urgent metabolic acidosis (older children)
2–5 mEq/kg IV over 4–8 hr
Stepwise; reassess blood gas before each further step
Label dose for older children and adults.
Neonates and children under 2 yr
Specialist order only outside resuscitation (for example NICU or PICU metabolic acidosis, hyperkalemia): 1 mEq/kg given slowly (8.4% = 1 mL/kg; 4.2% at 0.5 mEq/mL = 2 mL/kg)
Max 8 mEq/kg/day (label); avoid rapid injection
Not part of newborn resuscitation: AHA 2025 Part 5 (neonatal resuscitation) gives no bicarbonate recommendation; NASEMSO v3.0 finds no evidence to support routine bicarbonate in newborn resuscitation (p. 162). Epinephrine and volume are the drugs used. Rapid hypertonic injection can cause hypernatremia, a fall in cerebrospinal fluid pressure and intracranial hemorrhage; in arrest beyond the newborn period, the label weighs this against fatal acidosis.

Pediatric dosing is layered. Look to AHA/AAP 2025 first, for a stated dose. Next comes the NASEMSO National Model EMS Clinical Guidelines v3.0 (2022), then the US label. If no source gives a dose, none appears here. A pediatric maximum never climbs above the adult one (NASEMSO Universal Care Guideline, p. 13).

Weight-based dose checks: pediatric weight-based dosing.

Preparation & Administration

  • Push: 8.4% is given undiluted as an IV/IO push in arrest and toxicology; flush with saline before and after.
  • Infusion: 150 mEq in 1 L D5W (or a premixed 150 mEq/L bag) on a pump through a dedicated line.
  • Line and site: Use a large, well-running vein and watch the site: extravasated hypertonic bicarbonate causes chemical cellulitis and tissue necrosis, and rapid 8.4% through a poor or faulty cannula can cause thrombophlebitis.
  • Neonates and children under 2 yr: give slowly, using a lower concentration per the label; never a rapid push of 8.4% outside arrest.
  • Route: IV or IO only. Never ET: it injures the airway.
  • Ventilation first: Each mEq generates CO₂. Make sure the patient can exhale it (adequate spontaneous or assisted ventilation) before and after the dose.
Dosing Notes:
  • 8.4% = 1 mEq/mL, 7.5% = 0.9 mEq/mL, 4.2% = 0.5 mEq/mL, isotonic drip = 0.15 mEq/mL.
  • Give it in fractions and recheck the blood gas. You cannot predict how a given dose will land.
  • For renal and cardiac precautions, see Special Populations.
  • Differs from FDA label: on the label, the indication is metabolic acidosis, plus a rapid vial dose for cardiac arrest. Everything for sodium-channel blockers, salicylate and the ICU sits outside the label.

Contraindications & Precautions

Contraindications

  • Chloride loss: ongoing vomiting or continuous gastrointestinal suction (labeled contraindication)
  • Hypochloremic alkalosis from diuretics (labeled contraindication)
  • Endotracheal administration: never give by ET tube
  • Undifferentiated cardiac arrest: not indicated routinely

Precautions

  • Heart failure, severe renal insufficiency, edema with sodium retention: use with great care, if at all. The high sodium load can cause volume overload and pulmonary edema.
  • Inadequate ventilation: the CO₂ it generates raises PaCO₂ and can make respiratory and intracellular acidosis worse.
  • Hypokalemia and hypocalcemia: correct them during therapy. Never delay bicarbonate for life-threatening sodium-channel blocker cardiotoxicity. A rising pH drops K⁺ and ionized Ca²⁺, and that can bring on tetany or carpopedal spasm.
  • Corticosteroids or corticotropin: added sodium retention.
  • Neonates and children under 2 yr: rapid hypertonic injection carries a risk of hypernatremia and intracranial hemorrhage.

Hold / Reassess If

  • Serum pH above 7.55 (AHA 2025 Part 10 ceiling; target about 7.50): stop boluses; if intubated, control pH with minute ventilation
  • QRS has narrowed and blood pressure has recovered: stop boluses, continue only the infusion if needed
  • Na⁺ >150 mEq/L: reassess the need; do not exceed 155 mEq/L (AHA 2025 Part 10 ceiling); discuss with toxicology or the ICU team
  • K⁺ <3.5 mEq/L: replace K⁺ at the same time. Do not delay bicarbonate for life-threatening sodium-channel blocker cardiotoxicity. In salicylate poisoning, replace K⁺ at the same time (40–60 mEq KCl added to each liter of the infusion) and keep it normal. The urine will not alkalinize while K⁺ is low. Do not hold serum alkalinization for low K⁺. In non-urgent acidosis, correct K⁺ before escalating
  • Tetany, carpopedal spasm or low ionized Ca²⁺: stop and give calcium
  • Rising PaCO₂ or EtCO₂ that ventilation cannot clear
Same line as calcium: Calcium and bicarbonate form a precipitate of calcium carbonate. In hyperkalemia, give calcium first, flush thoroughly, then give bicarbonate. Separate lines are the other option.

Adverse Effects & Toxicity

Common

  • Hypernatremia: Na⁺ >150 mEq/L in 10% of ICU trial patients (4% of controls)
  • Metabolic alkalosis: twitching, irritability, tetany with overcorrection
  • Hypokalemia: the most expected complication of toxicology infusions
  • Low ionized calcium: more frequent with bicarbonate in ICU trials
  • Volume expansion: 50 mEq of sodium per 50 mL syringe of 8.4%
  • Infusion-site irritation

Serious / Life-Threatening

EffectRecognitionManagement
Severe alkalemia
pH >7.55, twitching, tetany, dysrhythmia; fatal alkalosis reported in TCA poisoning
Stop bicarbonate; 0.9% NaCl; KCl if hypokalemic; calcium gluconate for tetany; ammonium chloride only for severe alkalosis
Hypernatremia and volume overload
Rising Na⁺, crackles, falling SpO₂, edema
Stop or slow; treat volume overload
Hypokalemia
Falling K⁺, U waves, ectopy
Replace K⁺; add KCl to alkalinizing infusions
Hypercapnia, paradoxical acidosis
EtCO₂ and PaCO₂ rise, pH falls despite bicarbonate
Increase ventilation; hold further doses
Extravasation necrosis
Pain, swelling, blanching at the site
Stop; elevate; warmth; local lidocaine or hyaluronidase per label
Neonatal intracranial hemorrhage
After rapid hypertonic injection in neonates and infants
Prevent: slow rate, lower concentration per the label, max 8 mEq/kg/day

Overdose & Toxicity Management

  • Signs: metabolic alkalosis, hypernatremia, hypokalemia, low ionized Ca²⁺, tetany, volume overload.
  • Immediate management: stop all bicarbonate, including drips; blood gas, electrolytes and ionized Ca²⁺; 0.9% sodium chloride; KCl for hypokalemia; calcium gluconate for hyperirritability or tetany.
  • Antidote: none. Save the acidifying agent (ammonium chloride) for severe alkalosis.

Monitoring
ParameterWhen / How OftenTarget / Act If
Clinical: ECG (QRS, rhythm)
Continuous; 12-lead before and after boluses in toxicology
QRS still wide or dysrhythmia: repeat bolus only if pH is below the target of about 7.50 and the QRS is still wide; never give a bolus above pH 7.55; narrowed: switch to infusion
Clinical: ventilation, EtCO₂
Continuous in arrest, intubated or salicylate patients
EtCO₂ rises briefly after each bolus; sustained rise: increase ventilation. Salicylate on a ventilator: match pre-intubation minute ventilation
Clinical: volume status, lungs
Every hour during infusions
Crackles, falling SpO₂, edema: slow or stop; consider diuretic or dialysis
Clinical: IV or IO site
Before and during each push; hourly with infusions
Pain, swelling, blanching: stop, treat as extravasation
Laboratory: blood gas (pH, PaCO₂, HCO₃⁻)
After boluses and every 1–2 hr during alkalinization
Toxicology: target pH about 7.50, ceiling 7.55 (salicylate goal 7.50–7.55); ICU acidemia: pH ≥7.30; stop at pH 7.55. See pH and ABG panel
Laboratory: sodium
Every 2–4 hr during infusions or repeated boluses
Na⁺ >150 mEq/L: reassess need; toxicology ceiling 155 mEq/L
Laboratory: potassium
Every 1–2 hr in salicylate and TCA alkalinization
K⁺ <3.5 mEq/L: replace alongside bicarbonate (never delay it in sodium-channel blocker cardiotoxicity); salicylate: keep K⁺ normal
Laboratory: ionized calcium
With electrolytes during infusions
Low ionized Ca²⁺ or tetany: give calcium
Laboratory: urine pH (salicylate)
Every 1–2 hr
Target >7.5; not alkaline: check K⁺ and add bolus. See urine pH
Drug levels: salicylate
Serially until clearly falling (levels can peak late)
Hemodialysis recommended for altered mental status, acute respiratory distress needing oxygen, standard therapy failing (at any level) or salicylate >100 mg/dL (>90 with impaired kidney function); suggested at >90 mg/dL (>80 with impaired kidney function) or pH ≤7.20 (toxicology consensus thresholds; salicylate level)

Interactions & Compatibility

Clinically Significant Interactions

Drug / ClassEffectWhat To Do
Calcium salts (calcium chloride, calcium gluconate)
Calcium carbonate precipitate in the line
Never mix; flush between them or use separate lines
Catecholamines (norepinephrine, dobutamine, epinephrine)
Incompatible in the same line or bag
Separate line or lumen; flush before giving epinephrine through the same IV
Other K⁺-lowering therapy (insulin, albuterol, loop diuretics)
Additive fall in K⁺
Recheck K⁺ within 1–2 hr
Diuretics causing hypochloremic alkalosis
Worsened metabolic alkalosis
Contraindicated combination; correct chloride and volume instead
Corticosteroids, corticotropin
Additive sodium and water retention
Monitor volume status and Na⁺
Salicylate
Alkaline urine traps ionized salicylate and increases renal elimination
Used therapeutically in poisoning; expect falling levels
Class Ia/Ic sodium-channel blockers (flecainide, procainamide)
Bicarbonate may narrow the QRS; lidocaine is an option when it fails
AHA 2025 Part 10 (rec 6, COR 2b, C-EO): lidocaine may be reasonable for Ia/Ic cardiotoxicity; involve toxicology

IV Compatibility

  • Diluent for infusions: Use D5W (150 mEq/L). Commercial premixed isotonic bags need no dilution.
  • Incompatible: calcium-containing solutions, norepinephrine and dobutamine. Do not use any solution that shows a precipitate or haze.
  • Dedicated line for alkalinizing infusions where possible.
  • Verify with an institutional compatibility resource.

Special Populations
  • Pediatrics: Not for routine pediatric arrest. Save it for hyperkalemia and sodium-channel blocker toxicity. In pediatric DKA, avoid it unless hyperkalemia is life-threatening or venous pH is <6.9 with impaired cardiac contractility per the ISPAD 2022 guideline. It is linked to cerebral injury. No dose is shown. See the Pediatric Dosing table.
  • Neonates: Not part of newborn resuscitation. NASEMSO v3.0 finds no evidence for routine use, and AHA 2025 Part 5 makes no bicarbonate recommendation. Outside resuscitation it is a specialist order only. Give it slowly, at a lower concentration per the label (max 8 mEq/kg/day). Rapid hypertonic injection has been linked to hypernatremia and intracranial hemorrhage.
  • Pregnancy: There are no animal reproduction studies, and whether it causes fetal harm is unknown. The label advises use only if clearly needed. In cardiac arrest, sodium-channel blocker or salicylate poisoning, treat the mother. Maternal resuscitation comes first.
  • Lactation: US labeling has no data on it. Sodium and bicarbonate are normal plasma constituents. Do not withhold emergency treatment.
  • Older Adults: Start at the low end of the dosing range. Heart failure and reduced renal function are more common in this group.
  • Renal Impairment: Sodium retention and volume overload are more likely. Use smaller, stepwise doses and monitor Na⁺ and volume. In the ICU trials of severe metabolic acidemia, bicarbonate lowered new kidney replacement therapy starts overall. Patients with end-stage kidney disease were excluded.
  • Hepatic Impairment: No specific adjustment has been established. The kidneys and lungs clear it.
  • Obesity / Dosing Weight: No specific guidance has been established. Dose on actual body weight, and never exceed the adult dose in children.
  • Heart Failure / Edema: Use with great care, if at all, because of the sodium load. Monitor the lungs and SpO₂.

Field & Transport Considerations
  • Scope: Paramedic (many agencies carry 8.4% prefilled syringes), RN and critical-care transport. Scope varies by state and agency protocol.
  • Storage & Stability: Keep it at 20–25°C (68–77°F). Protect it from freezing and minimize heat exposure in vehicles. Do not use it if it is not clear, or if a precipitate is present.
  • Carried Concentration: Adult 8.4% (1 mEq/mL) and 4.2% (0.5 mEq/mL) syringes look alike. Read the percent and the mEq aloud. A 7.5% syringe holds 44.6 mEq, not 50 mEq.
  • Infusions in Transport: Confirm the bag recipe (mEq per liter and any added KCl), rate in mL/hr, last pH, urine pH and K⁺. Run it on a pump through a dedicated line, away from calcium and vasopressors; carry enough volume for the trip.
  • Salicylate Transfers: Avoid intubation in transport if possible. If intubated, set the ventilator to match the pre-intubation minute ventilation and check a blood gas early.
  • Crush / Rhabdomyolysis: Give volume first. Bicarbonate before crush release is expert practice, not a sourced recommendation. Treat hyperkalemia if it is present.
  • Handoff Essentials: indication; time and total mEq given; QRS before and after; last pH, PaCO₂, Na⁺ and K⁺; current infusion rate; IV site condition.

Clinical Pearls
No ventilation, no bicarb: Bicarbonate turns acid into CO₂, and the patient has to get rid of that CO₂. If they cannot exhale it, PaCO₂ climbs and the acidosis can get worse. Secure ventilation first. In an intubated salicylate patient, a low ventilator rate can be lethal.
Exam discriminator: overdose with a wide QRS: After an overdose, a wide QRS, a ventricular dysrhythmia or hypotension means sodium-channel blockade until proven otherwise. Reach for hypertonic sodium bicarbonate, not procainamide, which is itself a class Ia sodium-channel blocker. Lidocaine may be reasonable when bicarbonate fails in class Ia/Ic toxicity (AHA 2025 Part 10, COR 2b).
Bicarb alone does not fix hyperkalemia: Used by itself, it does not bring K⁺ down acutely. Calcium steadies the membrane. Insulin-glucose and albuterol move K⁺ into cells. Binders or dialysis take it out of the body. In hyperkalemic arrest, its effectiveness is not well established (AHA 2025 Part 10, COR 2b, C-EO). It is mainly used with severe metabolic acidosis.
Low K⁺ blocks urine alkalinization: In salicylate poisoning, the kidney holds on to K⁺ and gives up H⁺. The urine stays acidic even with the drip running. Put KCl in the bag and keep K⁺ normal.
What BICAR-ICU taught: In ICU patients with pH ≤7.20, a 4.2% infusion titrated to pH ≥7.30 did not lower 90-day mortality overall. It did cut new dialysis starts (about 35% vs 51%). The trial studied only pure metabolic acidemia (PaCO₂ ≤45 mmHg). It excluded DKA, toxic ingestion and bicarbonate loss. The mortality signal was confined to pH ≤7.10.
When the QRS will not narrow: Call toxicology early. AHA 2025 Part 10 lists these options. Lidocaine for class Ia/Ic cardiotoxicity (COR 2b, C-EO). Lipid emulsion for sodium-channel blocker poisoning refractory to other treatment (COR 2b, C-EO). VA-ECMO for refractory cardiogenic shock (COR 2a, C-EO).
Push, then drip: Boluses of 8.4% treat the wide QRS. The isotonic drip (150 mEq/L) holds the target. Don't try to resuscitate with a drip. Don't try to maintain with repeated amps.

Pharmacology

Mechanism of Action

  • HCO₃⁻ buffers H⁺ → H₂CO₃ → CO₂ + H₂O → the lungs exhale the CO₂ → blood pH rises (only if ventilation clears the CO₂).
  • Sodium-channel blockers: the sodium load helps overcome the channel blockade. The rise in pH may reduce drug binding → QRS narrows and blood pressure recovers. The mechanism may vary by drug.
  • Salicylate: alkaline blood keeps salicylate ionized → less of it moves into the brain and tissues. Alkaline urine traps ionized salicylate → faster renal excretion.
  • Alkalemia moves K⁺ into cells and drops ionized Ca²⁺ → hypokalemia and tetany with overcorrection.

Pharmacokinetics

RouteOnsetPeakDuration
IV/IO bolus
Immediate buffering in plasma
Minutes; reassess with a blood gas
Variable: until excess is excreted by the kidneys and CO₂ by the lungs
IV infusion (4.2% or 150 mEq/L)
Gradual
Target pH ≥7.30 reached at a median 4 hr in ICU trials
Variable: while infusing; depends on renal function
  • Half-life: not applicable. Bicarbonate is an endogenous ion (normal plasma level 24–31 mEq/L per the label), and the kidneys regulate it.
  • Metabolism: combines with H⁺ to form carbonic acid, then CO₂ and water.
  • Elimination: CO₂ leaves through the lungs. With normal kidneys, almost all filtered bicarbonate is reabsorbed (<1% excreted). Any excess is excreted, and that alkalinizes the urine.
  • Distribution: extracellular fluid. Na⁺ is the main extracellular cation.

Names & Classification
Generic Name
Sodium bicarbonate (NaHCO₃) injection; 84 mg = 1 mEq each of Na⁺ and HCO₃⁻
Brand Names
Generic products only in the US (8.4%, 7.5%, 4.2% and premixed 1.26% isotonic); commonly called "bicarb"
Pharmacologic Class
Systemic alkalinizing agent (buffer)
Therapeutic Class
Electrolyte replenisher; antidote for sodium-channel blocker cardiotoxicity; urinary alkalinizer
Controlled Substance
Not controlled
ISMP High-Alert
No: not on the ISMP list of high-alert medications in acute care settings
Look-Alike / Sound-Alike
No common name pair; the risk is concentration mix-ups: 8.4% (1 mEq/mL), 7.5% (0.9 mEq/mL) and 4.2% (0.5 mEq/mL) syringes

Related

References
  1. Hospira, Inc. (2025). Sodium bicarbonate injection, USP, 8.4% [prescribing information] (label revised May 2025; DailyMed version April 2026). DailyMed, National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=8664c7ce-707b-4c6c-9ce4-7160b5f877f8
  2. Cao, D., et al. (2025). Part 10: Adult and pediatric special circumstances of resuscitation: 2025 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation, 152(suppl 2), S578–S672. https://cpr.heart.org/en/resuscitation-science/cpr-and-ecc-guidelines/adult-and-pediatric-special-circumstances-of-resuscitation
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