Growing evidence indicates that patients face greater risk from surgeries performed at low-volume hospitals. Since the 1979 landmark study that examined mortality rates for 12 surgical procedures of varying complexity determined hospitals performing 200 or more surgical procedures a year had 25% to 41% fewer deaths than hospitals with lower volumes,1 more studies have produced similar results.2,3,4
High Volume vs. Low Volume
In its report, Ensuring Quality Cancer Care, the National Cancer Policy Board recommended that patients undergoing complicated cancer procedures associated with high mortality should receive care at high-volume facilities. Examples of such procedures include esophagectomy, pancreatectomy, removal of pelvic organs, and complex chemotherapy regimens.5
For high-risk, infrequently performed cancer operations, e.g., esophageal or pancreatic cancer, the relationship appears to be strongest. For example, a study found that the mortality rate for patients undergoing esophagectomy at high-volume (11+ procedures) hospitals was 3.4%, compared with 17.3% at low-volume hospitals performing up to 5 procedures.2 A similar relationship existed for pancreatectomy (5.8% vs. 12.9%), hepatic resection (1.7% vs. 5.4% and pelvic exenteration (3.7% vs. 1.5%).
In patients over 65 years old with pancreatic, lung, or colon cancer, life expectancy increased steadily when procedures were performed at high-volume hospitals.6 A U.S. News & World Report analyzed Medicare inpatients from 2010 through 2012 in hospitals that were in the bottom 20% in volume versus those in top 20%. It found that in low-volume hospitals:7
- Knee replacement surgery patients were at a nearly 70% greater risk to die
- Mortality risk for hip replacement patients was nearly 50% higher
- Patients with congestive heart failure and COPD had a 20% increased risk of death
Using the U.S. News & World Report analysis, Dr. John Birkmeyer, chief academic officer at Dartmouth-Hitchcock Medical Center in Lebanon, N.H., and pioneer in studying volume-outcome correlation, calculated that from 2010 through 2012 as many as 11,000 deaths nationally could have been prevented if patients who went to the lowest-volume fifth of the hospitals had gone to the highest-volume fifth. Since his calculations only evaluated mortality from five common procedures: bypass surgery without valve repair or replacement, elective hip and knee replacement, congestive heart failure and COPD, this number greatly underestimates the true impact on overall patient safety.
A large coalition of employers, the Leapfrog Group, is going as far as advising employees on which hospitals to select based on its set volume standards for five high-risk surgical procedures.8 It has been estimated that with full implementation nationwide, these standards would save 2,581 lives. Most lives saved would be for coronary-artery bypass graft (1,486), followed by abdominal aortic-aneurysm repair (464), coronary angioplasty (345), esophagectomy (168), and carotid endarterectomy (118). “You can save your life by picking the right place,” says Leah Binder, director of the Leapfrog Group, which emphasizes safety in measuring hospital performance.
Benefits of high-volume hospitals go beyond mortality rates. For patients undergoing prostatectomies, hospital volume is associated with the length of patient stay. For instance, patients treated at the lowest-volume hospitals stayed 9% longer than patients treated at the highest-volume hospitals (8.5 days vs. 7.8 days).5 In another study, rates of postoperative complications from a prostatectomy were lower (27% vs. 32%) at very high-volume hospitals than at low-volume hospitals.9
Outside greater mortality risk, low-volume care has other drawbacks. Joint replacement patients at low-volume hospitals had more readmissions requiring additional surgery due to infection or mechanical failure.10 One-year revision rates are nearly 20% higher for knee and hip replacement patients at the lowest-volume fifth of hospitals.7
However, it is important to understand that the relationship between higher volume and better outcomes is strong but not absolute or even linear. Some low-volume hospitals consistently do well while some high-volume facilities do not. It is for the patient to do some research, ask questions, and make an informed decision.
Before a complex procedure, patients should review the hospital’s performance ratings. Hospital Safety Score is a public service committed to driving quality, safety, and transparency in the U.S. healthcare system.11 Hospital Compare is a consumer Web site that provides information on how well hospitals provide recommended care to Medicare patients.12
Patients should ask the following questions:13
- Number of procedures of that kind done at the hospital annually?
- Surgeon’s and hospital’s infection rate for the procedure?
- Hospital’s and surgeon’s success rates for the procedure compared with national benchmarks?
- Is the surgical approach or device to be utilized for surgery new to the surgeon?
- Ease of obtaining medical documents and images for a second opinion?