Are clinical diagnoses prior to death reliable in critically ill patients?

Background

European and American studies have recently highlighted discrepancies between clinical diagnoses and post mortem findings in patients who died on the intensive care unit (ICU). This study set out to determine if similar findings were present in patients that died on an ICU in the UK.

Methods

Patients that died between January 1998 and June 2001 were identified from a database of ICU admissions. From this list, patients that had undergone a post mortem were identified and their medical notes reviewed retrospectively to establish the clinical diagnoses prior to death. These were compared to the post mortem cause of death and classified using the Goldman system. This system categorises discrepancies between clinical and post mortem diagnoses into three groups – major, minor and complete agreement. Major discrepancies were those where the principle, underlying cause of death was missed. Minor were missed diagnoses that may have contributed to death or important diagnoses that were unrelated to the cause of death. Complete agreement indicated concordance between clinical and post mortem diagnoses. Differences between the groups demographics were tested for using repeated measure ANOVA on ranks and chi-squared test.

Results

Nine hundred and thirty-nine patients died during the 3.5 year study period, of which 49 (5.2%) underwent a post mortem examination. Medical records were available and analysed for 38 of these patients. Major missed diagnoses were present in 18 cases (47%). In contrast, less than half of the cases (n = 16, 42%) showed complete agreement between clinical diagnoses and post mortem findings. There were no difference in age, admitting speciality, APACHE II score, predicted mortality or hospital length of stay between the three groups. Undiagnosed carcinoma, pulmonary embolism, left ventricular failure or infections represented the most frequently missed major diagnoses.

Conclusion

This small study has demonstrated that, in the critically ill, major underlying diagnoses were frequently missed prior to death. This may have led to unnecessary early death (if known for reversible causes) or unnecessary prolongation of life where terminal disease was present.