Your Medical Mind_ How to Decide What Is Right for You - Jerome Groopman [88]
At one a.m., the telephone rang and woke her up.
“We can get a liver from out of state,” the surgeon said. “Two other centers have passed on it because it came from an older person who had cancer and had chemotherapy. We aren’t sure, but this person also may have been exposed to hepatitis C.”
Ayesha took a moment to ponder what the surgeon saying. “You said Omar might die today.”
“That’s true. Of course, no one can ever say precisely when someone will die,” the surgeon replied. “But he is at the very edge.”
“I want you to go ahead,” Ayesha said.
We spoke with Omar and Ayesha about a year and a half after the transplant. He had spent two months in rehabilitation and then several more months at home to regain his strength with physical therapy. Now he was back at work full-time. “I feel great,” he told us. “I take my medications to prevent rejection of the graft, my antiviral therapy to keep hepatitis B from recurring, and the liver is working well. I know that the liver came from an older patient who had been treated for cancer, and it was rejected by two other centers. I realize how desperate the surgeons had to be to use it. But thank God they did. That liver saved my life.”
Things could have turned out very differently. Omar might not have survived the transplant despite the best efforts of his doctors. In fact, after Omar recovered, one of the residents told Ayesha that the transplant team hadn’t expected him to live. One of the senior physicians in the ICU had told a colleague that she’d never seen anyone that sick survive. Consider also that even if Omar survived, he may have been left severely debilitated, paralyzed, unable to speak, or even in a vegetative state.
These kinds of unknowns apply to many of the patients who populate our ICUs. Patients with catastrophic illnesses typically require “heroic measures.” These may include prolonged respiratory support on a ventilator, renal dialysis, catheters threaded into the chambers of their hearts, and a host of other invasive and risky interventions that offer no guarantee the patient will survive. And if he survives, in what condition?
Several studies have examined how accurately physicians predict the trajectory of disease in sick patients. Research done among patients in the ICU found that doctors are generally correct in giving a prognosis for moderately ill patients, but they aren’t very good at predicting the course of the sickest patients. In one study conducted in Paris, physicians erred on both sides—too optimistic and too pessimistic.
For that reason, critical care physicians have devised metrics to indicate when further treating severely ill patients would be “futile.” The mortality probability model (MPM-II) estimates the likelihood of death in the hospital. The model has been applied in studies of decision making about whether to admit a patient to the ICU and also to predict the prognosis after one day of intensive treatment there. Researchers from a consortium of hospitals in Massachusetts evaluated the MPM-II and concluded that “no system has been perfected to the point where decisions regarding an individual patient can be based on the estimated probabilities produced. This is especially true when considering denying a patient admission to the ICU on the basis of the estimated probability.”
The APACHE II score2 is another calculation based on organ function that’s frequently used to predict the probability of life or death in very sick patients. A study done at Guy’s Hospital in London applied this metric each day to thirty-six hundred patients in the intensive care unit. The researchers concluded that the APACHE II calculation was imperfect: One of twenty patients predicted to die actually lived, and most of those who survived had a good quality of life. Using such a system to decide when to withdraw treatment therefore might cost the life of some people who would otherwise survive with a reasonable