CONO Clinical Sciences flashcards

33 cards. Read the term and the definition here. The deck at the top of this page is optional.

Sensitivity

Proportion of patients with disease who test positive, calculated as true positives divided by true positives plus false negatives. High sensitivity makes a negative result useful for ruling out disease.

Specificity

Proportion of patients without disease who test negative, calculated as true negatives divided by true negatives plus false positives. High specificity makes a positive result useful for ruling in disease.

Positive predictive value

Probability that a patient with a positive test truly has the disease, equal to true positives divided by all positives. It falls sharply when disease prevalence in the tested population is low.

Likelihood ratio positive

Sensitivity divided by one minus specificity. It expresses how much a positive test raises the odds of disease; values above ten produce large, clinically important shifts.

Number needed to treat

Number of patients who must receive an intervention for one additional patient to benefit, calculated as one divided by the absolute risk reduction. Lower values indicate greater clinical efficiency.

Absolute risk reduction

Difference in event rates between control and treatment groups, expressed in percentage points. It reflects actual patient benefit and underlies the number needed to treat calculation.

Shared decision-making

Collaborative process in which the clinician explains options, benefits, harms, and uncertainties, and the patient's informed values guide the chosen plan, which is then documented.

Loading dose

Initial dose calculated as volume of distribution times target concentration divided by bioavailability. It rapidly achieves therapeutic concentration when the drug's half-life would otherwise delay steady state.

Half-life

Time required for plasma concentration to fall by half. Approximately four to five half-lives are needed to reach steady state during continuous dosing or to eliminate most drug after stopping.

Zero-order kinetics

Elimination at a constant amount per unit time because metabolic pathways are saturated. Small dose increases can then cause disproportionate and dangerous rises in drug concentration.

Therapeutic index

Ratio of toxic dose to effective dose. A narrow index means effective and toxic concentrations are close, requiring therapeutic drug monitoring of concentration, efficacy, and adverse effects.

Cytochrome P450 induction

Enzyme induction increases hepatic metabolism of substrate drugs, lowering their concentrations and potentially causing treatment failure. Classic inducers include rifampin, carbamazepine, and St. John's wort.

Sterile field

Area of sterile drapes and equipment that must never contact non-sterile objects and is never turned away from or reached across. Contamination requires replacement before the procedure continues.

Surgical time-out

Pause before an invasive procedure to verify patient identity, correct procedure and site, consent, allergies, and equipment availability, with all team members verbally confirming agreement.

Aseptic non-touch technique

Method protecting key parts and key sites from microbial contamination by avoiding direct contact. It applies to invasive procedures and to preparation of intravenous medications and dressings.

Primary survey

Sequential emergency assessment of airway, breathing, circulation, disability, and exposure. Each life threat is treated before proceeding, and the sequence restarts whenever the patient deteriorates.

Anaphylaxis first-line therapy

Intramuscular epinephrine given promptly, with airway support and fluid resuscitation as needed. Antihistamines and corticosteroids are adjuncts and must not delay epinephrine administration.

Defibrillation

Unsynchronized electrical shock for ventricular fibrillation or pulseless ventricular tachycardia. Delay reduces survival, so early recognition and immediate shock delivery are critical.

Informed consent elements

Disclosure of diagnosis, proposed intervention, alternatives, material risks, and expected benefits, plus patient comprehension, voluntariness, and authorization. All elements must be present and documented.

Decisional capacity

Task-specific ability to make a particular decision, assessed through understanding of information, appreciation of consequences, reasoning about options, and expression of a consistent choice.

Negligence elements

Four required elements: a duty of care, a breach of the standard of care, causation linking breach to harm, and actual damages. Failure to prove any element defeats the claim.

SBAR handoff

Structured communication using situation, background, assessment, and recommendation. It standardizes clinical handoffs and reduces omission of critical information during transitions of care.

Closed-loop communication

Sender directs a message to a named recipient, who repeats it back, and the sender confirms accuracy. The loop prevents errors from misunderstood orders in high-stakes team settings.

Two-challenge rule

Team safety tool in which a member voices concern twice, escalating to a supervisor or stop of the procedure if it remains unacknowledged, protecting the patient from harm.

Teach-back method

Communication technique in which the patient restates instructions in their own words, allowing the clinician to confirm comprehension and correct misunderstandings before discharge.

Secondary prevention

Early detection and treatment of established but asymptomatic disease through screening and prompt intervention, aiming to reduce progression, complications, and mortality rather than prevent onset.

Lead-time bias

Apparent survival gain from earlier detection alone, without any change in the actual time of death. Mortality endpoints rather than survival time avoid this distortion in screening studies.

Herd immunity

Indirect protection of unimmunized people when a sufficient proportion of the population is immune, reducing transmission. The required coverage threshold rises with pathogen transmissibility.

PICO question

Structured clinical question specifying population, intervention, comparison, and outcome. It guides literature searching and makes the evidence retrieval and appraisal process reproducible.

Confidence interval

Range of values likely to contain the true effect, reflecting estimate precision. An interval crossing no effect means the result is inconclusive regardless of statistical significance.

Plan-do-study-act cycle

Iterative quality improvement method: plan a change and predict results, do it on a small scale, study the measured outcome, then act by adopting, adapting, or abandoning the change.

Minimum necessary standard

Requirement to limit protected health information disclosed or accessed to the amount reasonably needed for the purpose, reducing privacy risk and supporting audit compliance.

Late entry documentation

Addition to a medical record made after the fact, clearly labeled as late with the actual time and reason, preserving the integrity of the original entry.