B-Sol

B-Sol is an FDA-approved, sterile, isotonic, physiological irrigating solution indicated as follows:

Established/approved use

• Extraocular and intraocular irrigation during ophthalmic surgical procedures (e.g., cataract extraction, vitrectomy, corneal transplantation, and other intraocular procedures) where irrigation of ocular tissue is required, typically for procedures expected to last less than 60 minutes of intraocular perfusion.

Other established surgical use

• As a general-purpose irrigating solution for other surgical procedures (e.g., urological, general surgical, or other body-cavity irrigation) where a physiologically balanced, isotonic electrolyte solution is needed to keep exposed tissue moist and to minimize tissue trauma from irrigation.

B-Sol is not indicated, and is not formulated, for injection, intravenous infusion, or as a general systemic intravenous fluid unless a specific product is separately labeled for that purpose.

Each 100 mL of Balanced Salt Solution typically contains the following physiological electrolytes and buffering agents (formulation may vary slightly by manufacturer/brand):

• Sodium Chloride 0.64 g
• Potassium Chloride 0.075 g
• Calcium Chloride Dihydrate 0.048 g
• Magnesium Chloride Hexahydrate 0.03 g
• Sodium Acetate Trihydrate 0.39 g
• Sodium Citrate Dihydrate 0.17 g
• Water for Injection, sufficient quantity

The resulting solution is sterile, non-pyrogenic, isotonic (osmolality approximately 300 mOsm/kg), and buffered to a pH of approximately 7.4–7.6, closely resembling the ionic composition of aqueous humor and other body fluids. It contains no preservatives or antimicrobial agents.

B-Sol is a sterile, non-pyrogenic, isotonic electrolyte solution formulated to closely approximate the physiological ionic composition of body fluids, particularly the aqueous humor of the eye. It is supplied as a clear, colorless solution in a sterile container intended for use as an irrigating fluid during surgical procedures.

Because its electrolyte profile, pH, and osmolality are matched to normal ocular and tissue fluid, B-Sol helps maintain normal cellular function and tissue hydration of exposed structures (such as the corneal endothelium) during surgery, in contrast to non-physiological irrigants (e.g., plain saline or water), which can cause tissue swelling and damage on prolonged contact.

B-Sol contains no preservatives; each container is intended for single-patient, single-procedure use, and any unused portion must be discarded.

B-Sol belongs to the class of ophthalmic and surgical irrigating solutions (physiological/isotonic electrolyte irrigants), used as an adjunct during surgical procedures rather than as a systemically administered drug.

Balanced Salt Solution works by physical and physiological principles rather than a pharmacodynamic drug action. Its electrolyte composition (sodium, potassium, calcium, magnesium, chloride, acetate, citrate) and osmolality closely match those of extracellular fluid and aqueous humor.

• Sodium and chloride maintain osmotic pressure and normal fluid distribution across cell membranes.
• Potassium supports normal neuromuscular and cardiac electrical activity.
• Calcium is essential for maintenance of cellular membrane integrity, cell-to-cell junctions (including corneal endothelial tight junctions), and neuromuscular function.
• Magnesium acts as a cofactor for numerous enzymatic reactions and helps maintain cell membrane stability.
• Acetate and citrate serve as bicarbonate-precursor buffers, helping maintain physiological pH.

Because Balanced Salt Solution is isotonic and ionically balanced, irrigation with it minimizes osmotic and ionic stress on delicate tissues such as the corneal endothelium and intraocular structures, reducing the risk of cellular swelling, dysfunction, and damage that can occur with non-physiological irrigating fluids.

B-Sol is administered topically as a continuous or intermittent irrigating stream directly onto or into the surgical field (e.g., the anterior/posterior chamber of the eye or another body cavity), using sterile tubing and an administration set with an air-inlet, under aseptic conditions and direct visualization by the operating surgeon. It is not swallowed, injected intramuscularly, or infused intravenously.

Because B-Sol is used topically as a surgical irrigant rather than absorbed systemically in clinically significant amounts, it has no established clinically significant systemic drug-drug interactions.

The main interaction of clinical concern is with additives mixed into the solution: introducing other drugs or substances into B-Sol without established compatibility and stability data may alter its pH, osmolality, or sterility and has been associated with corneal decompensation and endothelial damage. Any additive should only be used if specifically indicated and proven compatible.

B-Sol is generally very well tolerated because its composition closely matches physiological fluid. Reported adverse effects are primarily local, related to the surgical procedure and irrigation itself rather than to the solution's chemistry:

• Corneal edema or swelling
• Bullous keratopathy
• Corneal endothelial decompensation, particularly with prolonged irrigation, trauma to the endothelium, or use of unauthorized additives
• Postoperative intraocular inflammation
• Rarely, hypersensitivity reactions to a solution component

Most of these effects are related to surgical trauma, prolonged perfusion time, or additive use rather than being direct toxic effects of B-Sol itself.

B-Sol is used topically as a surgical irrigant with negligible systemic absorption. Formal pregnancy category studies have not been established for this route of use. As with any surgical procedure and product used during surgery, B-Sol should be used in pregnant or breastfeeding patients only if clearly needed for the planned surgical procedure, with the potential benefit justifying any theoretical risk; a physician should be consulted regarding the overall surgical plan in pregnancy or lactation.

• B-Sol must not be injected or given intravenously; it is intended solely as a topical surgical irrigating solution.
• Use strict aseptic technique; the solution contains no preservative, so any unused portion must be discarded and the container must not be reused or used for more than one patient.
• Inspect the container before use — do not use if the solution is discolored, cloudy, or contains particulate matter, or if the seal is not intact.
• Avoid adding other drugs or substances to the solution unless compatibility has been established, since additives have been linked to corneal decompensation.
• Use with caution in diabetic patients undergoing vitrectomy, as lens changes (clouding) have been reported in this population with intraocular irrigation.
• Prolonged intraocular perfusion time and any additional trauma to the corneal endothelium during irrigation increase the risk of postoperative corneal edema and decompensation (see Side Effects).
• B-Sol is intended strictly for the surgical/procedural indication for which it is labeled and should not be used outside that context.

Because B-Sol is administered topically under direct surgical control rather than by patient self-administration, a conventional "overdose" is not applicable in the way it would be for an oral or systemic drug. Excessive or prolonged irrigation may theoretically increase the risk of local tissue effects such as corneal edema or endothelial decompensation (see Side Effects). If excessive volumes are inadvertently administered or a systemic exposure is suspected (e.g., from misuse via an unintended intravenous route), the surgical team or attending physician should be alerted immediately and the patient should receive prompt medical evaluation and supportive care; in an emergency, contact emergency medical services or a poison control center immediately.

Store B-Sol between 2°C and 25°C (36°F–77°F). Do not freeze. Protect the container from physical damage and keep it in its original packaging until immediately before use. Use only if the seal is intact and the solution is clear and free of particulate matter. Keep out of reach of children. Discard any unused portion after opening, as the product contains no preservative.

Pediatric patients: B-Sol is used in pediatric ophthalmic and other surgical procedures in the same manner as in adults, with the volume determined by the surgeon based on the size of the surgical field and duration of the procedure; no pediatric-specific dose adjustment is required since it is not systemically dosed.

Elderly patients: No specific dose adjustment is required, as administration is determined by the surgical procedure rather than patient age.

Diabetic patients: Use with caution during vitrectomy, as lens changes have been reported with intraocular irrigation in this population (see Precautions and Warnings).

Renal or hepatic impairment: No specific dose adjustment is established or generally required, given the topical, non-systemic nature of use; however, the operating physician should use clinical judgment regarding total irrigation volume in patients with significant fluid or electrolyte disorders.

B-Sol is used only for the duration of the surgical or procedural irrigation for which it is required — it is not a continued or take-home therapy. Intraocular perfusion time is generally kept to under 60 minutes per standard surgical protocol; the exact duration is determined by the operating surgeon based on the specific procedure.

Balanced Salt Solution is classified as a sterile ophthalmic/surgical irrigating solution — a physiological, isotonic, balanced electrolyte solution — rather than a pharmacologically active drug class.

Balanced Salt Solution does not act through a receptor-mediated pharmacological mechanism. Instead, its mode of action is physicochemical: by matching the electrolyte concentration, pH, and osmolality of normal body/ocular fluid, it maintains the normal osmotic and ionic environment of exposed tissues (e.g., the corneal endothelium) during surgical irrigation, thereby preventing the cellular swelling, ionic imbalance, and tissue damage that non-physiological irrigating fluids (such as plain water or hypotonic/hypertonic saline) can cause.

B-Sol is used in pediatric patients undergoing ophthalmic or other surgical procedures requiring tissue irrigation, using the same physiologically balanced formulation as in adults. There is no separate weight-based or age-based dosing regimen, since the product is applied topically to the surgical field and the volume used is determined by the surgeon according to the size and duration of the procedure rather than by patient age or weight. Safety and effectiveness are supported by its long-standing use as a standard surgical irrigant across pediatric and adult surgical populations when used as labeled and under appropriate surgical supervision.