Those results are often from tests done on a patient's final day in the hospital, researchers found - and up to one in seven of them may be abnormal.

It's not necessarily a bad thing to discharge a patient while waiting on a blood test or biopsy, according to Dr. Christopher Kim, a hospitalist at the University of Michigan Health System in Ann Arbor. But in those cases, he added, communication can't end when the patient goes home.

"Patients should know that there are going to be some tests and study results that are pending when they leave the hospital, and it's important for them to discuss with their care providers what those tests are exactly and when those tests might be expected to come back," Kim, who wasn't involved in the new study, told Reuters Health.

"A lot of patients assume that if they don't hear from their healthcare provider that no news is good news, and that's absolutely incorrect. No news could mean the care providers never got to look at those test results," he said.

The issue of coordination of test results and other clinical findings came into the spotlight last month with a New York Times story about 12-year-old Rory Staunton who died of septic shock after doctors at NYU Langone Medical Center didn't communicate about signs and lab results suggesting he was very sick.

The new study included 6,700 patients who had close to 700,000 different pathology tests done at any time during their stay at one Australian hospital.

Three percent of results hadn't been reviewed when patients were discharged - most often findings from tests done on their last day in the hospital.

That could include tests that take a couple of days to run, or common checks of electrolytes that have been stable for a while and so aren't seen as pressing, Kim said.

But half of those initially unchecked results still hadn't been reviewed another two months later, according to findings published Monday in the Archives of Internal Medicine.

Overall, close to 38 percent of patients had at least one pending or otherwise not-reviewed lab result at the time of discharge. And one in seven of those unchecked results was abnormal, Enrico Coiera of the University of New South Wales in Sydney and colleagues found.

The study didn't say whether or not lack of knowledge about any of those abnormal tests affected how well patients did after they left the hospital.

"Those tests that we order on patients on the day of their discharge - sometimes they are unnecessary," said Dr. Kevin O'Leary, who has studied hospital discharges at the University of Northwestern Feinberg School of Medicine in Chicago.

"The treating physician, one of the reasons they might not know about the abnormal tests results is that they assume they're normal and they don't even look."

Sometimes there's also confusion about which doctor is in charge of checking those labs - which could include HIV tests or blood cultures - O'Leary, who didn't participate in the new research, told Reuters Health.

That's why it's important for patients to be proactive and ask if any test results haven't come back when they're sent home, he added.

Kim agreed and said that at discharge, patients should also have a general check-in with their doctor that includes going over their medications and any other treatment-related questions.

SOURCE: bit.ly/MbBLbb Archives of Internal Medicine, online August 13, 2012.

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