Background The goal of this study was to determine if ED surge and end-of-shift assessment of patients affect the extent of diagnostic tests, therapeutic interventions and accuracy of diagnosis prior to referral to internal medicine.

Methods This study was a health records review of consecutive patients referred to the internal medicine service with an ED diagnosis of heart failure, chronic obstructive pulmonary disease (COPD) or sepsis starting 1 December 2013 until 100 cases for each condition had been obtained. We developed a scoring system in consultation with emergency and internal medicine physicians to uniformly assess the completeness of treatments and investigations performed. These scores, expressed as percentage of possible points, were compared at high and low surge levels and at middle and end of shift at time of patient referral. End of shift was defined as 7:30–8:30, 15:30–16:30 and 23:30–00:30 as our shift changes occur at 8:00, 16:00 and 24:00. Rate of admission, diversion to other services and diagnosis disagreements were also assessed.

Results We included 308 patients (101 heart failure, 101 COPD, 106 sepsis) with a mean age of 74.7. Comparing middle of shift to end of shift, the mean scores were 91.9% versus 91.8% (difference 0.1% (95% CI −2.4 to 3.0)) for investigations and 73.0% versus 70.4% (difference 2.6% (95% CI −1.8 to 7.4)) for treatments. Comparing low to high surge times, the mean scores were 92.1% versus 91.7% (difference 0.4% (95% CI −1.2 to 2.4)) for investigations and 71.4% versus 73.6% (difference −2.2% (95% CI −5.6 to 1.3)) for treatments. We found low rates of diversion to alternate services (8.9% heart failure, 0% COPD, 6.6% sepsis) and low rates of diagnosis disagreement (4.0% heart failure, 10.9% COPD, 8.5% sepsis).

Conclusions We found no evidence that surge levels and end of shift impact the extent of investigations and treatments provided to patients diagnosed in the ED with heart failure, COPD or sepsis and referred to internal medicine.