Выбрать главу

"When we draw blood for blood gases, we routinely also order the usual blood count plus electrolytes. And with heart attacks, we order biomarkers."

"If they were ordered, how come there's no mention of it on the order sheet, and why aren't the results on the ER note? The blood gases are there."

Matt took the sheets from Georgina and quickly looked them over. He shrugged. "I don't know, maybe because they normally go in the hospital record, but since she died so quickly, she never got a hospital record." He shrugged again. "I suppose they are not on the order sheet because it's a standing order for all myocardial infarction suspects. I did mention sodium and potassium were normal in my note, so someone called the results to the ER desk."

"This isn't a big-city ER," Georgina explained. "It's rare to have a death here. Usually people get admitted, even those in bad shape."

"Could we call the lab and see if they could possibly locate the results?" Jack asked. He did not quite know what to make of this serendipitous discovery or whether it would have any meaning, but he felt obligated to see where the lead would take him.

"Sure," Matt said. "We'll have the clerk call up there. Meanwhile, we've got to get back to work. Thanks for coming by. It's strange you didn't find any pathology, but it's nice to know we didn't miss anything that could have saved her."

Five minutes later, Jack found himself in the tiny, windowless office of the evening laboratory supervisor. He was a large, heavyset man with heavily lidded eyes that gave him a sleep-deprived appearance. He was staring at his computer monitor with his head tilted back. His nametag read: "Hi, I'm Wayne Marsh."

"I don't see anything under Patience Stanhope," Wayne said. He had been very obliging when the ER had called, and invited Jack up to his office. He'd been impressed with Jack's credentials, and if he'd noticed the badge said New York rather than Massachusetts, he didn't mention it.

"I need a unit number," Wayne explained, "but if she wasn't admitted, then she didn't get one."

"What about through billing?" Jack suggested. "Somebody had to pay for the tests."

"Nobody's in billing at this hour," Wayne said, "but didn't you mention you have a copy of the ER record. That will have an ER accession number. I can try that."

Jack handed over the ER notes. Wayne typed in the number. "Here we go," he said as a record flashed up on the screen. "Dr. Gilbert was right. We did a full blood count with platelets, electrolytes, and the usual cardiac biomarkers."

"Which ones?"

"We do CKMB and cardiac-specific troponin T on arrival at the ER with repeats at six hours postadmission and twelve hours postadmission."

"Was everything normal?"

"Depends on your definition of normal," Wayne said. He twisted his monitor screen in its base so Jack could see it. He pointed to the blood-count section. "There's a mild to moderate rise in the white count, which is expected with a heart attack." His finger then went to the electrolytes. "The potassium is at the upper edge of normal. Had she lived, we would have wanted to check that, for obvious reasons."

Jack inwardly shuddered at the mention of potassium. The frightening episode with Laurie's potassium during her ectopic pregnancy emergency was still fresh in his mind despite its being over a year ago. Then his eyes happened to notice the biomarker results. To his surprise, the tests were negative, and he immediately called it to Wayne 's attention. Jack's pulse ratcheted up. Had he stumbled onto something significant?

"That's not unusual," Wayne said. "With improved response times to nine-one-one calls, we often get our heart attack victims into the ER within the three- to four-hour interval it takes for the biomarkers to rise. That's one of the reasons we routinely repeat the test at six hours. Jack nodded as he tried to sort out the discrepancy this new information provided. He didn't know whether he'd forgotten or never knew there was such a delay before bio-markers become positive. Not wishing to appear overly uninformed, he worded his next questions carefully. "Does it surprise you that an earlier bedside biomarker assay was positive?"

"Not really," Wayne said.

"Why not?"

"There are a lot of variables. First off, there's about a four percent false negative result as well as a three percent false positive. The tests are based on highly specific monoclonal antibodies, but they are not infallible. Secondly, the bedside kits are based on troponin I, not T, and there's a lot of bedside kits on the market. Was the bedside assay for troponin I alone or with myoglobin?"

"I don't know," Jack admitted. He tried to remember what was written on the box in Craig's doctor's bag, but he couldn't visualize it.

"That would be important. The myoglobin component becomes positive faster, often within as little as two hours. What's the time frame on this case?" He picked up the ER note and read aloud: "Patient's husband states chest pain and other symptoms developed between five and six p.m., probably closer to six." Wayne looked up at Jack. "She arrived in the ER close to eight, so the time frame is about right as far as our results are concerned, since it was less than four hours. Do you know when the bedside assay was done?"

"I don't," Jack said. "But if I had to guess, it would be somewhere around seven thirty."

"Well, that does seem marginal, but as I said, the bedside tests are made by a host of companies with widely differing sensitivities. The kits also should be carefully stored, and I believe there's an expiration date. Frankly, that's why we don't use them. We much prefer the troponin T, since it's made by only one company. We get very reproducible results with a short turnaround time. Would you like to see our Abbott analyzer? It's a beauty. It measures absorbance spectrophotometrically at four hundred fifty nanometers. It's right across the lab if you want to take a gander."

"Thank you, but I think I'll pass," Jack said. He was getting in technically way over his head, and his visit at the hospital had already been twice as long as he had planned. He certainly didn't want to keep Latasha waiting. He thanked Wayne for his help and returned quickly to the elevator. As he rode down to the first floor, he couldn't help but wonder if Craig's bedside biomarker assay kit had somehow been defective, either from improper storage or from being out of date, and had given a false positive. What if Patience Stanhope did not have a myocardial infarction? All at once, yet another dimension was opening up, particularly with the services of a toxicologist available. There were a lot more drugs that deleteriously affected the heart than those capable of simulating a heart attack.

Jack jumped into the car and quickly dialed Latasha's number. As he'd done with his call to Alexis, he put his phone on speaker and placed it on the passenger seat. By the time he was driving out of the hospital parking lot, Latasha answered.

"Where are you?" she asked. "I'm here in my office. I got two hot pizzas and two large Cokes. Where are you at?"

"I'm just leaving the hospital. I'm sorry it has taken as long as it has, but I learned something possibly important. Patience Stanhope's biomarker test was negative when it was read by the hospital analyzer."

"But you told me it was positive."