2021_Book_TextbookOfPatientSafetyAndClin

17 Patient Safety in Internal Medicine
remaining 20% during transcription and verification
(12%) or pharmacy dispensing (11%) [42].
Any type of error can result from different proximal
causes and a single proximal cause can lead
to a variety of errors. For example, lack of drug
knowledge can cause wrong choice, dose, frequency,
route, or technique of administration.
Wrong dose can result from lack of drug or
patient knowledge, slip or memory lapses, transcription
errors, and so on. Behind proximal
causes there are latent causes or system failures.
Leape et al. counted 16 different system failures,
but the first seven have in common an impaired
access to information and accounted for 78% of
all MEs, whereas work and staff assignment have
been associated to a broad range of errors such as
slips, dose- and identity-checking, breakdown of
allergy barriers [41].
Frequency of MEs/ADEs in IM has been
poorly investigated. An 8-month prospective,
cross-sectional study found that 89% of the
patients experienced at least one ME during hospitalization,
with a mean of 2.6 errors per patient
or 0.2 errors per ordered medication. More than
70% of MEs happened during prescription. The
most prevalent prescription MEs were inappropriate
drug selection, prescription of unauthorized
drugs or for untreated indications. The most
involved drugs were cardiovascular agents followed
by antibiotics, vitamins, minerals, and
electrolytes [43].
MEs are more frequent and severe in the socalled
high-risk situations due to high-risk
patients and/or providers, medications, or settings.
High-risk patients are younger or older,
multi-morbid or chronic patients (with liver and/
or renal impairment), on polypharmacy [44–47].
High-risk providers are younger or not expert
providers [48, 49]. High-risk systems are hospitals
delivering acute care (e.g. error rates are
likely higher for drugs administered intravenously
compared with other routes [50]) and
high-risk medications are the so-called high-alert
medications (HAMs) and look-alike, sound-alike
medications (LASA). HAMs have a heightened
risk of causing significant patient harm when
used erroneously. They include drugs with a low
therapeutic index and drugs at a high risk of harm
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when administered by the wrong route or at
wrong dosage or when other system errors occur.
The acronym A-PINCH serves as a reminder of
them, it stays for Anti-infective, Potassium and
other electrolytes, Insulin, Narcotics and other
analgesics, Chemotherapeutic agents, Heparin
and other anticoagulants. LASA are drugs with
similar names or boxes [50].
Although there is no standard definition, polypharmacy
is generally defined as the concurrent
use of five or more medications [51], over-thecounter
and complementary medicines included.
It increases MEs because it reduces compliance
and favors timing and/or dosing errors, duplications,
or omissions. Drug–drug and drug–disease
interactions, instead, increase ADEs [51]. It is
particularly risky in IM as it cares for polypathological
patients, even if internists could be
more aware and cautious, as supposed by a
French study [52].
Care transition is a key moment of care for
several reasons, medication safety included. It
occurs when a patient moves to, or returns from,
home, hospital, residential care setting or simply
outpatient clinics, general practitioners’ office or
consultation. In care transition unintentional
(changes not supported by clinical reason) and/or
undocumented (motivated but not documented
changes) medication discrepancies can occur
[53]. They are MEs that can lead to ADEs. A
mean of 1.72 unintentional discrepancies per
patient have been reported at hospital admission
(0.16 per patient potentially harmful) and 2.05
per patient (0.3 potentially harmful) at discharge
from hospital [54].
Causes of MEs are numerous, so multiple
simultaneous interventions are needed to reduce
their rate and impact [36]. In recent years, information
technology has been established as a cornerstone
for MEs reduction. Recent meta-analysis
highlighted that in hospital computerized physician’s
order entry is associated with a greater than
50% decline in pADEs [55], and the use of barcode
assisted medication administration substantially
reduced the rate of MEs and pADEs [56].
Medication reconciliation (MR) is recommended
to avoid unintentional discrepancies
between patients’ medications across transitions