The demographic characteristics of patients presenting for ambulatory surgery are changing—they are older and sicker, a databa se review has confirmed. The analysis concluded that the proportion of ambulatory surgery patients having challenging medical conditions that influence their health status increased significantly between 2006 and 2010.
“Although the criteria for outpatient surgery selection have become less restrictive in recent years, the trend regarding the use of ambulatory surgery in patients with challenging medical conditions is not well known in the [United States],” said Eric B. Rosero, MD, an assistant professor of anesthesiology and pain management at UT Southwestern Medical Center, in Dallas. “However, at the beginning of 2017, the National Center for Health Statistics released the ambulatory surgery component of the 2010 National Hospital Ambulatory Medical Care Survey (NHAMCS). That provided us an opportunity to study some trends over the years.”
To help gain perspective on these trends, Dr. Rosero, along with co-investigator Girish P. Joshi, MBBS, MD, merged and analyzed data from the 2006 National Survey of Ambulatory Surgery and the 2010 NHAMCS with an eye toward characterizing trends in the proportion of patients with challenging conditions undergoing ambulatory surgery. Challenging medical conditions were defined as age over 80 years or a diagnosis of any of the following: pulmonary hypertension, obstructive sleep apnea, heart failure, cardiac arrhythmia, cardiac valve disease, chronic renal failure, diabetes mellitus, post–organ transplant, post–coronary angioplasty/stent, or post-implantation of a heart assist device or a pacemaker/implantable cardioverter defibrillator.
Challenging Conditions Increase
“Interestingly,” Dr. Rosero said, “the mean age of patients having ambulatory surgery increased from 52.2 to 53.7. This was a statistically significant difference [P<0.0001] and confidence intervals don’t overlap, so it looks like it’s real.” The investigators also found that the proportion of patients with a number of challenging comorbidities also showed a statistically significant increase between 2006 and 2010, including:
- obstructive sleep apnea (0.32% – 0.45%);
- heart failure (0.13% – 0.22%);
- pacemaker/AICD (0.15% – 0.26%);
- cardiac arrhythmias (0.24% – 0.55%);
- chronic renal failure (0.52% – 0.76%); and
- diabetes mellitus (1.21% – 1.71%).
“In total,” Dr. Rosero noted, “the proportion of patients with challenging conditions increased from 12.8% to 13.9%, which was also statistically significant.”
Although the overall age of the patients increased between the two study years, the investigators were surprised to see that the proportion of octogenarians actually decreased, from 9.5% in 2006 to 7.9% in 2010 (P<0.0001). Challenging conditions that either remained static or decreased between 2006 and 2010 included pulmonary hypertension, post–organ transplant, valve disease, and implantation of heart assist devices or coronary stents.
“This analysis suggests that sicker patients are increasingly being offered outpatient surgery in this country,” Dr. Rosero concluded.
The analysis drew several questions from Dr. Rosero’s audience, including session co-moderator Shaina Drummond, MD, an assistant professor of anesthesiology and pain management at UT Southwestern Medical Center. “Was there any differentiation with respect to [monitored anesthesia care] cases versus general cases in these patients?” she asked.
“We didn’t look at that,” Dr. Rosero replied, “because the definition of type of anesthesia changed a little bit between the two surveys. So if we had analyzed that, the results wouldn’t be very reliable.”
Co-moderator Claude Abdallah, MD, an associate professor of anesthesiology and pediatrics at George Washington University Medical Center, in Washington, D.C., asked about next steps in the study. “I think the next step would be to use larger databases and compare the outcomes in those types of patients to determine trends,” Dr. Rosero said. “The problem is we don’t have much big data on ambulatory surgery, so we may try to use some state databases.”
“We are currently looking at data from New York, California and Florida, which have inpatient, outpatient and ER databases,” added Dr. Joshi, a professor of anesthesiology and pain management at UT Southwestern Medical School, in Dallas. “We are analyzing these data to give us trends and information about unplanned admissions and readmissions. This will help us see whether these patients are appropriate for ambulatory surgery.”