Medication Errors: Case-Based Review Notes

Overview of Medication Errors

• Daily alerts warn of potential medication errors, but human errors still occur despite error-reduction systems.
• Clinicians need skills to recognize and reduce error risk and identify errors before they reach the patient.
• This article provides an overview, case reviews, and strategies for preventing medication errors.

Pathophysiology of an Error

• The brain’s creativity can lead to errors; planning and execution steps can both fail.
• Planning errors (deficient knowledge or misapplied rules) vs execution errors (slips or lapses).
  • Planning errors: mistakes due to deficient training or nonroutine tasks.
  • Execution errors: slips (attention failures, interference) and lapses (memory omissions).
• Medication use involves both planning and execution errors; thus, prevention must address both domains.

Definition of a Medication Error

• ISMP defines a medication error as any error occurring in the medication use process; a preventable event that may lead to inappropriate medication use or patient harm.
• Types of errors:
  • Error of commission (planning): doing something incorrectly on purpose.
  • Error of omission (execution): failure to take an appropriate step.
• Either type can lead to undesirable outcomes or adverse events.
• An adverse drug event is harm related to medication use.
• Summary: medication errors are common, preventable, and have substantial patient harm potential.

Inpatient Medication Errors and Use

• Common hospital errors: prescribing, dispensing, administration, patient compliance.
• Medication use process has multiple risk points; ISMP identifies 10 key elements to strengthen (Table 1):
  • Patient information
  • Drug information
  • Adequate communication
  • Drug packaging, labeling, and nomenclature
  • Medication storage, stock, standardization, and distribution
  • Drug device acquisition, use, and monitoring
  • Environmental factors
  • Staff education and competency
  • Patient education
  • Quality processes and risk management
• Goal: strengthen these elements to reduce errors and patient harm.

Impact of Errors

• IOM 1999 report: estimated $44{,}000$–$98{,}000$ deaths per year due to medical errors; about 2 jumbo jet crashes per week; half of those deaths due to medication errors.
• Medication errors associated with increased mortality, cost, and longer length of stay.
• Inpatient medication error rates historically cited as 3 ext{--}6.9 ext{ ext{%}}, with higher rates when accounting for underreporting; preventable adverse drug events estimated at $380{,}000$–$450{,}000$ annually; overall harm estimates are higher when calculated across systems.
• Harm to patients: estimated $1{,}500{,}000$ patients annually in the US harmed by medication errors.
• A Massachusetts study across 6 community hospitals (18 months): about $3.8{,}000{,}000$ patients affected by serious preventable inpatient medication errors.
• Human and system costs: inpatient preventable medication errors may total around $16.4{,}billion$ annually in US healthcare costs.

Impact of Technology

• Electronic health records (EHRs) adoption: 2014 survey showed 75.5 ext{ ext{%}} of nonfederal US acute care hospitals with basic EHRs; 34.4 ext{ ext{%}} with comprehensive EHRs in all units.
• Technologies reducing errors include:
  • Computerized provider order entry (CPOE)
  • Automated medication dispensing systems (robotics, cabinets)
  • Bar-code medication administration (BCMA)
  • Electronic medication reconciliation
• Effectiveness:
  • CPOE: error reductions of 55 ext{ ext{%}}–83 ext{ ext{%}}.
  • Bar-code dispensing: reduces dispensing errors by about 31 ext{ ext{%}}.
  • BCMA: reduces administration errors by 54 ext{ ext{%}}–87 ext{ ext{%}}.

Impact of Nurses

• Nurses are a critical last line of defense; detection often highest in paper-based systems.
• Interception rates (nurses):
  • Wrong drug, dosage, or route: 48 ext{ ext{%}} intercepted.
  • Transcription errors: 23 ext{ ext{%}} intercepted.
  • Dispensing errors: 37 ext{ ext{%}} intercepted.
  • Overall: nurses intercepted 58 ext{ ext{%}} of all medication errors.
• With IT systems, error rates generally decrease; the nurse’s role remains vital for detection and prevention.

Nursing Strategies for Avoiding Errors

• Three core strategies identified by critical care nurses: Identification, Interruption, Correction.
• Identification (right patient, right drug, right dose, right time, right route; extended to right reason):
  • Know patient, players, plan of care, and surveillance.
  • Policy/procedure alignment; use of double-checks and cross-checks.
  • Involve patient and family in verification.
• Interruption management: reduce disruptive interruptions; offer assistance when safe; verbally clarify; ensure focus during high-risk tasks.
• Correction: persistently verify and confirm the plan of care; refer to standards or consult experts; involve another nurse or physician when needed.
• Additional resources: teammates, patient/family, and cross-disciplinary input.
• To reduce errors, implement system safeguards through policies and procedures.
• Case example illustrating breakdowns in collaboration (outdated med list, lack of verification, and no hold parameters).

High-Alert Medications

• ISMP defines high-alert medications as agents with increased risk of significant patient harm if used in error; require extra safety steps.
• Common high-alert classes: insulin, narcotics, anticoagulants, among others.
• Case examples illustrate why heightened safeguards are needed:
  • Case: double-concentrated heparin dispensed; no barcode administration; reliance on expectation (confirmation bias) led to bypassing the double-check; need mandatory double-checks and barcode use.
  • Case: 100 units of insulin U-500 administered instead of 20 units; many providers/nurses are unfamiliar with U-500; ISMP recommendations: express dosage in actual units (U-500) and confirm syringe type with the patient; involve patient in verification; ensure precise dosing and unit-clarity.
  • Case: opiate infusion via pump misprogramming; if infusion pump not preprogrammed in library, avoid bypass; confirm pump settings with colleagues/pharmacists; consider double-checks for high-risk infusions.
  • Case: warfarin self-administration by patient; lack of awareness by clinicians; ensure documentation and verify last dose with patient before administration; engage patient in the care process.
• Practical prevention steps include expressing doses in actual units, verifying syringe types, and involving patients in high-risk dosing questions.

Prevention of Future Medication Errors

• Ongoing education to reduce risk:
  • Targeted continuing education in critical care, especially for high-alert meds.
  • Didactic and supervised clinical instruction on dosing, monitoring for toxicity, and safe administration/handling.
  • Updates from ISMP newsletters; review institution policies; regular safety guideline reviews.
  • Preparation and periodic review to build confidence in preventing errors.
• Quality processes and risk management: implement and refine workflows to minimize errors; learn from incidents to improve systems.

Reporting and Learning from Errors

• Nurses should immediately report incorrect medication use and associated events.
• Use incident/safety reports to identify system flaws, improve processes, and develop risk management strategies.
• What to report: how the event occurred, deviations from normal process, rationale (if known), risky behaviors, and ideas to prevent recurrence.
• Follow institutional reporting policies; the objective is to enable analysis and systemic improvements.
• Nurses can contribute by participating in drug utilization evaluations, medication use training, and recommending changes to medication administration timing to reduce workload.

Conclusion

• It is unrealistic to expect zero medication errors; even with high-dose administration, some errors will occur.
• The focus should be on identifying, interrupting, and correcting errors, especially for high-alert medications.
• A multi-faceted approach exists (CPOE, automated dispensing, BCMA, medication reconciliation, standardized ordering/administration, training).
• Nurses play a crucial role in preventing both immediate and future medication errors through vigilance, communication, and system improvements.

Case Studies

• Case 1: Identification/Outdated Medication History
  • Elderly patient admitted for hypotension; two home antihypertensives given, worsening hypotension.
  • Contributing factors: outdated medication list used; nurse entered carvedilol and nifedipine; physician did not review current meds; pharmacist did not clarify need to continue home meds.
  • Outcome: preventable adverse event due to poor interprofessional communication; solution: open communication among patient, nurse, pharmacist, and physician; verify current meds.
• Case 2: Interruption and Medication Form Error
  • Pediatric cefdinir intended PO; given IV due to syringe shortage and pharmacy ran out; pharmacist did not adequately review; nurse interrupted while programming infusion pump.
  • Solution: implement a no-interruption policy during medication administration; ensure accurate dosing form selection; minimize interruptions to prevent similar errors.
• Case 3: Correction and Dosing Confusion (Weight-based Dose)
  • Underweight adult given weight-based sulfamethoxazole-trimethoprim (160 mg/kg) instead of 160 mg; closed technology system with robot distribution.
  • Contributing factors: confusion between mg/kg and mg; lack of dose-review by pharmacist and nurse unfamiliar with the drug’s dosing.
  • Prevention: clarify orders, review drug information, verify with provider/pharmacist, and involve patient/family; emphasize high-alert dosing review.
• Case 4: High-Alert Medications and Confirmation Bias (Heparin)
  • Double-concentrated heparin dispensed vs single-concentrated order; no barcode administration; check bypassed due to routine practice.
  • Lesson: enforce double-checks and barcode verification for high-alert meds; address confirmation bias and ensure adherence to safety protocols.
• Case 5: Insulin U-500 Dosing Misunderstanding
  • Patient received 100 units of U-500 instead of 20 units; many providers are unfamiliar with U-500; syringe type decision adds risk; ISMP recommends expressing dose in actual units and confirming syringe type with patient.
  • Prevention: patient involvement in dosing confirmation; ensure unit clarity and syringe confirmation before administration.
• Case 6: Opiate Infusion Pump Misprogramming
  • Infusion pump not preprogrammed; nurse unfamiliar with high-risk meds and their pump settings; bypassing pump safety features.
  • Prevention: verify pump library settings; use double-checks for high-risk infusions; seek pharmacist confirmation when uncertain.
• Case 7: Undocumented Warfarin Administration (Discharged/ED)
  • Patient self-administers warfarin at 5 pm in ED; administration not documented; nurse did not confirm last dose upon transfer to critical care.
  • Prevention: verify last dose with patient, document administration, and ensure credit/traceability of anticoagulant use across transitions.

Summary of Key Takeaways

• Medication errors arise from planning and execution failures (slips and lapses) and are influenced by system design, human factors, and communication.
• ISMP’s 10 key elements of medication use provide a framework for reducing risk; focus on patient/drug information, communication, labeling, storage, device use, environment, education, and risk management.
• Technology (CPOE, BCMA, automated dispensing, reconciliation) significantly reduces errors but does not eliminate them; human factors and process redesign remain essential.
• Nurses are a critical line of defense; strategies include thorough identification, minimizing interruptions, and correction by consulting standards and others when needed.
• High-alert medications require extra safeguards, explicit dosing units, and patient involvement to prevent dangerous errors.
• Ongoing education, safety culture, and robust reporting mechanisms are necessary to identify and remediate system weaknesses and prevent recurrence.
• Even with extensive safeguards, a residual risk remains; the goal is to minimize harm by proactive identification, interruption, and correction of potential errors.