The Scrub Person's Medication Responsibilities
While the surgical technologist does not prescribe or independently administer medications, the scrub person is directly responsible for receiving, identifying, labeling, and managing every medication and solution that enters the sterile field. Medication errors in the OR - most commonly from unlabeled containers or look-alike solutions - are a well-documented preventable safety hazard, making pharmacology knowledge directly applicable to daily practice, not just exam content.
Local Anesthetics
Local anesthetics block nerve conduction by inhibiting sodium channels, preventing the transmission of pain signals. Agents differ primarily in onset speed and duration:
- Lidocaine - fast onset, intermediate duration; among the most commonly used local anesthetics for infiltration and blocks.
- Bupivacaine - slower onset, long duration; often chosen when extended postoperative pain control is desired.
- Ropivacaine - similar duration profile to bupivacaine with a somewhat improved cardiac safety margin.
Local anesthetic systemic toxicity (LAST) is a rare but serious complication from inadvertent intravascular injection or excessive dosing, presenting with central nervous system symptoms (perioral numbness, tinnitus, seizure) and potentially cardiovascular collapse. While anesthesia manages treatment, the surgical technologist should recognize that this is a possible complication tied to local anesthetic administration.
Epinephrine and Vasoconstrictors
Epinephrine is frequently combined with local anesthetic to prolong its effect and reduce bleeding at the injection site through vasoconstriction. It is avoided in end-arterial tissue - fingers, toes, nose, ears, and penis - because unopposed vasoconstriction in these areas can cause ischemia and tissue necrosis, a frequently tested safety point.
Hemostatic Agents
Beyond mechanical and thermal hemostasis, several pharmacologic and biologic agents assist with bleeding control: topical thrombin converts fibrinogen directly to fibrin at the bleeding site; tranexamic acid (an antifibrinolytic) reduces blood loss in select procedures by preventing clot breakdown; and fibrin sealants combine fibrinogen and thrombin components to form an active clot matrix directly at the application site.
Irrigation Solutions
| Solution | Application |
|---|---|
| Normal saline | General-purpose wound and cavity irrigation |
| Sterile water | Occasionally chosen for its cytolytic (cell-lysing) effect in select oncologic applications |
| Antibiotic irrigation | Diluted antibiotic solution applied directly to the wound per surgeon order |
| Nonelectrolyte irrigants (glycine, sorbitol, mannitol solutions) | Required for monopolar resectoscope procedures (e.g., TURP) because electrolyte-containing solutions would conduct current away from the intended target |
Antibiotics and Surgical Site Infection Prevention
Prophylactic IV antibiotics are generally administered by anesthesia within about 60 minutes prior to incision, timed to achieve adequate tissue concentration at the moment of incision - a core component of national surgical site infection prevention initiatives. Redosing may be required for prolonged procedures or significant blood loss, per facility protocol and the antibiotic's half-life.
Contrast and Diagnostic Agents
Iodinated contrast media is used for intraoperative studies such as cholangiography; patients with known iodine or shellfish allergy history require advance communication with the surgical team, since an allergic reaction to contrast can occur intraoperatively. Dyes such as methylene blue or indigo carmine are used to visually identify anatomical structures (ureters, fistula tracts) or confirm the integrity of an anastomosis.
Medication Safety on the Sterile Field
- Every medication or solution delivered to the sterile field is labeled immediately - name, strength/concentration, and (when relevant) the time - before any similar-looking container is introduced.
- The scrub person and circulator verbally confirm each medication passed to the field, functioning as an active read-back safety check.
- Unlabeled solutions or medications on the sterile field must be discarded; assuming identity based on appearance or memory is never acceptable.
- Medications with similar packaging (e.g., saline vs. local anesthetic vs. contrast in similar syringes) represent one of the most common sources of OR medication error, requiring deliberate visual and verbal verification every time.
Connecting Pharmacology to Practice
Surgical pharmacology on the CST exam is tested through applied scenarios far more than isolated drug-fact recall: a question may describe a bleeding situation and ask which agent is appropriate, or describe a medication safety lapse and ask what should have happened. Building your understanding around purpose and safety context, rather than memorizing an isolated drug list, will serve you far better on exam day.