The WHO definition includes ADE’s caused by medication errors. Medication errors can occur at any stage in the medication system—from ordering through administration to the patient. Some of these medication errors are harmless, some cause injury, and some are "near misses" (fail to cause injury by chance or because they are intercepted before the medication is administrated to the patient).

The Institute for Healthcare Improvement formed the Idealized Design of the Medication System (IDMS) Design Group in May 2000. A group of 25 physicians, pharmacists, nurses, and statisticians established an aim to design a medication system that is safer by a factor of 10, and more cost effective than that currently in use. For ADE’s this means the number that now occur in a month would be approximately the total ADE’s that occur in an entire year.

Integral to the IDMS aim was to establish a measure for ADE’s that is accurate and without bias, especially undercounts. The decision of the Design Group was to measure harm not errors. Only ADE’s that cause harm to the patient will be counted. Harm is temporary or permanent impairment of physical or psychological body function or structure. In the NCC MERP Index for Categorizing Errors (September 2000), the following categories are excluded:

Category A: Circumstances or events that have the capacity to cause error

Category B: An error occurred but the error did not reach the patient.

The categories E through I of the NCC MERP Index that cause harm are included in the definition of an ADE. They are:

This kit includes an operational definition of an ADE and a method to obtain the measurement. The kit is divided into 6 parts:

1. ADE Trigger Chart Review Tool
2. Adverse Drug Event Chart Review Prep
3. Adverse Drug Event Chart Review Procedure
4. Process of Investigation for Positive Trigger Points
5. Weekly Sampling Plan and Chart Review Summary Template
6. Case Study Training Aid

This tool has identified 24 triggers that provide "clues" to studying patient charts for potential ADE’s. Additional "floating triggers" may be added for your healthcare system. All triggers that are positive should be investigated for possible harm to the patient.

The tool is given in Attachment 1. The chart face sheet should give all the demographics needed to fill out that portion of the worksheet. This includes the patient name, the medical record number admission and discharge dates and the patient age. The preparation, procedure and process given in the next 3 parts are essential in completing the use of this tool.

Look up each of the following drugs. What type of adverse drug reaction would result in the administration of that drug (e.g. protamine sulfate – patient would receive if s/he was given excess heparin)?

1. Diphenhydramine (Benadryl)
2. Vitamin K (Aqua-mephyton)
3. Flumazenil (Romazicon)
4. Droperidol (Inapsine); Ondanestron (Zofran); Promethazine (Phenergan); Hydroxyzine (Vistaril); Trimethobenzamide (Tigan); Prochlorperazine (Compazine);

or Metoclopramine (Reglan)

5. Naloxone (Narcan)
6. Diphenoxylate (Lomotil), loperamide (Imodium), kaopectate, pepto-bismol
7. Sodium Polystyrene (Kayexalate)

Look up each of the following lab tests/results. What type of adverse drug reaction would result in these findings?

1. PTT > 100 seconds
2. INR > 6
3. WBC < 3000
4. Serum glucose < 50
5. Rising serum creatinine
6. Clostridium difficile positive stool
7. Digoxin level > 2
8. Lidocaine level > 5
9. Gentamicin or Tobramycin levels: peak > 10, trough > 2
10. Amikacin levels: peak > 30, trough > 10
11. Vancomycin level > 26
12. Theophylline level > 20

Why might each of the following findings indicate an adverse drug event has occurred?

1. Oversedation, lethargy, fall, hypotension
2. Rash
3. Abrupt medication stop
4. Transfer to a higher level of care

Read through the chart paying particular attention to the following sections:

Obtain financial data in order to count both medications and individual dosages

If you find a trigger, check "yes" to indicate it was present in the chart. Then read through the appropriate parts of the chart to determine whether the finding was related to medication administration. Sometimes professional judgment will be required to make this determination. For example, a patient received an anti-emetic an hour after a narcotic. If the patient continued to receive the narcotic without further anti-emetic, the incidents are probably unrelated. If the patient continued to require anti-emetics after narcotics, an adverse drug event probably occurred. Some adverse drug events will result in more than one trigger. Use best judgment in determining the number of ADE’s in that situation.

[Note: we are including adverse drug events that led to hospitalization or required transfer to the hospital in our review (e.g. took medication, became hypotensive, fell, and was admitted to the hospital). We are not including intentional drug overdoses as ADE’s, nor is patient death considered "transferred to a higher level of care" in this review.]

The chart review using trigger points can be very valuable in finding ADE’s if the thought process used in the investigation is standardized. The following standardized process will be followed in the chart review.

Diphenhydramine Diphenhydramine, or Benadryl, is frequently used for allergic reactions to drugs but can also be ordered as a sleep aid, a pre-op/pre-procedure medication, or for seasonal allergies. If the drug has been administered, review the chart to determine if it was ordered for symptoms of an allergic reaction to a drug administered either during the hospitalization or prior to admission.

Vitamin K Determine whether Vitamin K was used as a response to a prolonged protime or INR. If either lab value is high, review the chart for evidence of bleeding. Look in the lab reports for a drop in hematocrit or for guiac-positive stools. Check the progress notes for evidence of excessive bruising or a GI bleed. Less likely, a hemorrhagic stroke or other internal bleeding might have occurred.

Flumazenil (Romazicon) This drug reverses benzodiazepine drugs. Determine why the drug was used. If hypotension or marked, prolonged sedation occurred following benzodiazepine administration, an ADE has occurred.

Anti-Emetics Nausea and vomiting can be the result of drug toxicity or overdose, particularly in patients with impaired renal function. Drugs such as theophylline preparations frequently cause nausea and vomiting when levels get high. Antiemetics are also commonly administered to patients post-operatively or those receiving chemotherapy. Professional judgment must be used in these situations to determine if an ADE has occurred.

Naloxone (Narcan) This is a powerful narcotic antagonist. If it has been used, overdosage of narcotics is a frequent finding. If it was used and the patient's condition didn't change, doubt excessive narcotic administration.

Antidiarrheals Look for antibiotic-caused C. difficile infections. If the C. difficile was not ordered and significant diarrhea occurred in a patient receiving multiple antibiotics, it is likely that an ADE occurred.

Glucose < 50 Not all patients will by symptomatic. Just because serum glucose is low does not mean an ADE occurred. Look for associated use of insulin or oral hypoglycemics or evidence of symptoms and administration of glucose (orally or IV). In addition, look for signs or symptoms in the nursing notes about lethargy, shakiness, etc.

C. difficile positive stool If a patient is on multiple antibiotics, this is a likely complication.

PTT > 100 seconds This is not an infrequent occurrence when patients are on heparin. As with Vitamin K, look for evidence of bleeding to determine if an ADE has occurred. Use professional judgment for patients with high PTTs receiving heparin during a surgical procedure.

INR > 6 Again, not an infrequent occurrence when patients are on coumadin. Look for evidence of bleeding to determine if an ADE has occurred.

WBC < 3000 In some cases, this will occur in response to drug administration. Follow the WBC counts throughout the admission and see what has happened. If leukopenia is related to drugs such as Indocin, a drop in WBCs should be evident. Don't include patients currently receiving chemotherapy.

Drug levels With any drug level above normal, look for evidence of drug side effects. If any signs or symptoms have occurred, it is considered an ADE. Not all above normal levels will result in an ADE.

Oversedation, lethargy, falls Look in the physician progress notes, nursing or multidisciplinary notes for evidence of oversedation, lethargy and falls. If found, look for a relationship between the event and administration of a sedative, analgesic, or muscle relaxant. Falls related to an ADE and resulting in the admission are included. Intentional overdose resulting in sedation is not included.

Rash There are many causes for a rash. Look for evidence that the rash is related to drug administration, including overuse of antibiotics resulting in yeast infections.

Abrupt medication stop In the order sets, whenever "hold" or "stop" medication orders appear, look for the reason this was done. Frequently it indicates an event of some kind.

Transfer to a higher level of care This includes either within the institution, to another institution from yours, or to your institution from another.

A chart review summary template to record your results is given in Attachment 2. The above steps should be repeated for an additional 3 weeks to obtain a monthly estimate of the ADE rate per admission and the ADE rate per dose.

Using the ADE chart review procedure in Part 3 (page 4), the reviewer completed the following:

1. Reviewed the physician’s orders looking for any of the identified triggers, especially the trigger drugs.
2. If triggers were found, reviewed progress notes, nursing notes, multidisciplinary notes for evidence of an ADE. If an ADE was found, then determined the harm level.
3. Reviewed laboratory findings for any of the lab triggers. If triggers were found, reviewed progress notes, nursing notes, multidisciplinary notes for evidence of an ADE. If an ADE was found, then determined the harm level.
4. Obtained financial data in order to count both medications and individual dosages.

Medical Record Number _____________ Patient’s Name_____________________

Admission date ___________________ Patient’s Age______________________

Total medications for this patient (financial data) ______________

Total doses of medications for this patient (financial data) ______________

Total ADE’s for this patient ______________

Harm category for ADE ______________

Reviewer (circle) MD RN RPh SN other: ______________

Category E: contributed to or resulted in temporary harm to the patient and required intervention

Category F: contributed to or resulted in temporary harm to the patients and required initial or prolonged hospitalization

Category G: contributed to or resulted in permanent patient harm

Category H: required intervention to sustain life

Category I: contributed to the patient’s death

Definition: a defect in the preparation, dispensing and/or administration of the medication

Example: the patient received the wrong medication; the patient received the wrong dose of a correct

Medication

2. Information Retrieval and Processing

Definition: information that is critical to the safe and effective use of medication is either available and not

used or is not available.

Example: no thorough knowledge of medications taken at home, history of medication reactions and allergies

are either poorly documented or not available, drug interaction information not known

Definition: patient is on the correct medication but blood level varies above and/or below therapeutic level

Example: lab values such as a PTT, INR and renal/hepatic clearance are not used in a standardized manner or

not used at all to establish therapeutic dose levels

Definition: identifiable and occasionally, rare, risks known to the clinician

Example: nausea and vomiting after opioid use, dyspepsia with certain antibiotic use, uncontrollable bleeding in a

patient after a correct dose of an anticoagulant

TYPE [Select as many items as are applicable from this section.]

70.1 Dose Omission [The failure to administer an ordered dose to a patient before the next scheduled dose, if any.

This excludes patients who refuse to take amedication or a decision not to administer.]

70.2 Improper Dose

70.2.1 Resulting in Overdosage

70.2.2 Resulting in Under dosage

70.2.3 Extra Dose

70.3 Wrong Strength/Concentration

70.4 Wrong Drug

70.5 Wrong Dosage Form

70.6 Wrong Technique (includes inappropriate crushing of tablets)

70.7 Wrong Route of Administration

Route Given Route Intended

70.7.1 IV Gastric

70.7.2 Intrathecal IV

70.7.3 IV Oral

70.7.4 IV IM

70.7.5 IM IV

70.7.6 Other

70.8 Wrong Rate

70.8.1 Too fast

70.8.2 Too slow

70.9 Wrong Duration

70.10 Wrong Time [Admin. outside a predefined time interval from its scheduled admin. time, as defined by each health care facility]

70.11 Wrong Patient

70.12 Monitoring Error (includes Contraindicated Drugs)

70.12.1 Drug-Drug Interaction

70.12.2 Drug-Food/Nutrient Interaction

70.12.3 Documented Allergy

70.12.4 Drug-Disease Interaction

70.12.5 Clinical (e.g., blood glucose, prothrombin, blood pressure)

70.13 Deteriorated Drug Error (Dispensing drug which has expired)

70.14 Other [Any medication error that does not fall into one of the above]