Electronic responses to:

NEWS
Doctors warned to be wary of new drugs

Deborah Josefson
BMJ 2002; 324: 1113 [Full text]

Send response to journal:
Re: CONSEQUENCE OF DRUG, DOSE, AND RISK FOR MEDICAL ERROR
 

Email Bill D. Misner Ph.D.:
drbill@omnicast.net

SUMMARY POINTS -Patient education by the medical office staff insures higher compliance and exact prescription use reducing the risk of overdose or misuse

-Checks and balances for review of prescription and dose reduces risk of overdose resulting in medical error

-Clinical pharmacy services and hospital pharmacy staffing variables are associated with reducing medication error rates

-Preclinical prescription screening tools for reducing risk of excess dose for some prescription drugs may be limited to lethal dose 50% [LD50] from animal studies

The practice of modern medicine has limited power remarkably dependant upon a conservative approach for generating good and reducing the risks of additional harm. [1] Clinicians are human; no physician has yet to report a lifetime of error-free medicine. Verification of dose and schedule are critical steps in the practice of medicine. Less than optimal dosing can result in reduced efficacy, and an overdose can cause profound toxicity and death. A model example is presented in the systematic format for reviewing chemotherapy orders reducing the potential for medication errors. Patient safety is further enhanced by careful verification of dosages and schedules. [2]

One-third of the disciplinary actions against physicians in 1990 involved prescriptions for controlled or high abuse drugs. Problems involving the prescribing of controlled medications may occur because of overdose dependence or use by known drug abusers. A common problem facing the physician is the identification of potential overdose victims and addicted patients. [3]

Antidepressant drugs are among the most common drugs involved in fatal poisoning and large variations between antidepressant drugs have been noted. There are humane and practical reasons for developing a pre- clinical indicator of toxicity in overdose for this rapidly expanding group of drugs. Buckley & McManus examined what preventative overdose measures. They concluded the best current pre-clinical indicator of fatal toxicity in humans is the LD50 from animal studies. [4] What the lethal dose is for 50% of test animal subjects presents a wide margin for error for a small but undetermined percent of prescription-dosed human subjects.

Overdose of prescription drugs typically occurs through two venues, patient abuse and/or dose prescription exceeding patient tolerance. The patients may either accidentally or purposely overdose a medication. Conservative standard prescriptions may occasionally exceed a patient's physical tolerance. During one study of 836 patients who were diagnosed for lung obstructive chronic disease, cirrhosis, gastrointestinal hemorrhage and cancer, 6,308 drug prescriptions were written. An "Expert Drug System" was employed to evaluate these prescriptions and dose according to patient characteristics, such as age, weight, height, sex, renal function and liver function. The system recommends the correct dose, detects interactions and adverse effects and makes suggestions in pregnancy and lactation. The expert system detected 458 overdoses and 33 underdoses, mainly in antibiotics and antiulcer drugs, and 1,722 interactions. The frequency of drug overdose and underdosages in patients admitted in this university hospital is relatively high. [5]

Copenhagen University Hospital evaluated 170 prescriptions in a project at Copenhagen University Hospital Pharmacy. Prescriptions were collected at two private pharmacies in Copenhagen during a two-week period in October 1995. The prescriptions contained an average of 1.5 errors and 89% had errors with only 11% without fault. The three most frequent errors of omission were code of department, inadequate identification of the physician and indications of use. [6] Were these prescriptive dose misdirections limited only to these 2 European hospitals examined or is this a commonly widespread phenomena? Are hospitals and health systems in the USA using the best practices that are available today to order, dispense, and monitor medications for patients?

The direct relationships and associations among clinical pharmacy services, pharmacist staffing, and medication errors in United States hospitals were evaluated. A database was constructed from the 1992 National Clinical Pharmacy Services database. A total of 429,827 medication errors were evaluated from 1081 hospitals. Medication errors occurred in 5.22% of patients admitted to these hospitals each year. Hospitals experienced a medication error every 22.04 hours (1 in every 19.13 admissions). These findings suggest that at minimum, 90,895 patients annually were harmed by medication errors in American general medical- surgical hospitals. Factors associated with increased medication errors/occupied bed/year were drug-use evaluation increased staffing of hospital pharmacy administrators/occupied bed, and increased staffing of dispensing pharmacists/occupied bed. Factors associated with decreased medication errors/occupied bed/year were presence of a drug information service, pharmacist-provided adverse drug reaction management, pharmacist- provided drug protocol management, pharmacist participation on medical rounds, pharmacist-provided admission histories, and increased staffing of clinical pharmacists/occupied bed. As staffing increased for clinical pharmacists/occupied bed from the 10th percentile to the 90th percentile, medication errors decreased from 700.98 +/- 601.42 to 245.09 +/- 197.38/hospital/year, a decrease of 286%. Specific increases or decreases in yearly medication errors associated with these clinical pharmacy services in the 1081 study hospitals were drug-use evaluation (21,372 more medication errors), drug information services (26,738 fewer medication errors), adverse drug reaction management (44,803 fewer medication errors), drug protocol management (90,019 fewer medication errors), medical round participation (42,859 fewer medication errors), and medication admission histories (17,638 fewer medication errors). Overall, clinical pharmacy services and hospital pharmacy staffing variables were associated with medication error rates. [7] Though such results should help hospitals reduce the number of medication errors that occur each year, in the meantime, one medical error may result in needless loss of a human life.

Studies using physician implicit review have suggested that the number of deaths due to medical errors in USA hospitals is also too high. Reviewer estimates of whether deaths could have been prevented by optimal care and of the probability that patients would have lived to discharge or for 3 months or more if care had been optimal were rated. Similar to previous studies, almost a quarter (22.7%) of active-care patient deaths were rated as at least possibly preventable by optimal care, with 6.0% rated as probably or definitely preventable. They estimated that the percentage of patients who would have left the hospital alive had optimal care been provided was 6.0%. However, after considering 3-month prognosis and adjusting for the variability and skewness of reviewers' ratings, clinicians reestimated that only 0.5% of patients who died would have lived 3 months or more in good cognitive health if care had been optimal, representing roughly 1 patient per 10,000 admissions to the study hospitals. [8]

Though 9,999 persons survive standard medical treatment but one life is errantly lost, that is one life that otherwise should have been saved. When the present order of medical staffing is increased in order to reduce case overload, with responsible 2nd and 3rd party prescription-treatment dose review prior to dose application, the consequences of risk for medical error from higher dose prescriptions may be decreased.

In my opinion, we need more people involved on the "treatment team" in order to resolve medical prescription error. George Dunea summarized, "Diagnostic mistakes could further be avoided by recognizing the underlying factors that distract attention, such as boredom, frustration, anger, work overload, or environmental factors, such as noise or heat. Errors may be due to poor skills, faulty judgment, flawed data, or bias, haste, not seeing the patient as a whole, and not failure to spend the time to diagnose from prescribing without complete knowledge. Unwanted outcomes may also result from leaving major decisions in the hands of inexperienced junior staff; these often also represent system failures and should be corrected by better deployment of medical personnel. [9] A very good example worthy of review is finding others to lighten the load by numerically increasing professional assistance for the "treatment team." Nurse Practitioners assigned to the medical staff were observed to effectively expand treatment capacity and reduce the workload's impact of risk to create a medical error. [10] The new drugs require study in depth review before an effective dose-effect is accurately applied. This calls to question for a published drug review by an independant physician's group which details dose outcome to the general patient population to whom the drug may help or may be contraindicated.

REFERENCES

[1] Smith R. Why are doctors so unhappy? BMJ 2001;322:1073-1074.

[2] Schulmeister L. Preventing chemotherapy dose and schedule errors. Clin J Oncol Nurs. 1997 Jul;1(3):79-85.

[3] Voth EA, Dupont RL, Voth HM. Responsible prescribing of controlled substances. Am Fam Physician. 1991 Nov;44(5):1673-8.

[4] Buckley NA, McManus PR. Can the fatal toxicity of antidepressant drugs be predicted with pharmacological and toxicological data? Drug Saf. 1998 May;18(5):369-81.

[5] Codina C, Corominas N, Roca M, Tuset M, del Cacho E, Soy D, Gomez B, Perez M, Masso J, Ribas J. [Comparative study of an expert system application in the prescription of medications] Med Clin (Barc). 1997 Oct 25;109(14):538-41.

[6] Andersen SO, Beurling C. [Prescriptions, prescription-writing errors and patient safety] Ugeskr Laeger. 1997 Mar 3;159(10):1454-8.

[7] Hayward RA, Hofer TP. Estimating hospital deaths due to medical errors: preventability is in the eye of the reviewer. JAMA. 2001 Jul 25;286(4):415-20.

[8] Bond CA, Raehl CL, Franke T. Clinical pharmacy services, hospital pharmacy staffing, and medication errors in United States hospitals. Pharmacotherapy. 2002 Feb;22(2):134-47.

[9] Dunea G, Views and Reviews, Soundings, Mistakes. BMJ 1998;316:1026 ( 28 March )

[10] Horrocks S, Anderson E, Salisbury C, Systematic review of whether nurse practitioners working in primary care can provide equivalent care to doctors. BMJ 2002; 324: 819-823.

Bill Misner, Ph.D. <drbill@omnicast.net> The author has no competing interests in this subject area.