Preventive strategies, not epidemiological studies, are needed

EDITOR—Vincent et al estimated that about 11% of hospital admissions in two hospitals were associated with an adverse event and argue for a larger study to document the prevalence of such adverse events in the United Kingdom.1 Their estimate of adverse events occurring in hospital is well within the statistical boundary of previous estimates obtained by much larger studies in the United States2 and Australia3; their argument for yet another large study therefore seems weak. Sufficient evidence already exists; there is an urgent need now for strategies to prevent or reduce the error, not for another descriptive epidemiological study.

Death, cardiac arrest, and unplanned admissions to an intensive care unit are probably the most serious among the adverse events. Most of these events have their genesis in general wards; they are not sudden or unpredictable, because they are usually preceded by signs of clinical instability. Because of this, medical emergency teams have been developed and tested.4

The system has three components: identifying high risk patients at an early stage; providing a rapid response; and providing feedback data on the effectiveness of the medical emergency team. Under this system, when a patient's clinical condition is unstable (as judged by specific criteria) a call is immediately made to the team for intervention. We postulate that the system is an effective strategy to reduce adverse events occurring in hospital.

In a prospective study conducted in a 300 bed tertiary referral teaching hospital in Melbourne, after the medical emergency team system was implemented the incidence of cardiac arrest was halved (unpublished data). Moreover, in a six month prospective study the incidence of cardiac arrest, deaths, and unplanned admissions to the intensive care unit in one hospital with a medical emergency team was lower than the incidence in two hospitals …