Ambulatory Surgery - Purpose of this Report


This report, Ambulatory Surgery in Pennsylvania, begins a new phase of Council activity, which is intended to collect and report information about medical treatment provided in the ambulatory setting. By its design, it is intended as a prototype. It includes only one quarter of data, which will allow for only simple observations. It was not intended to do more. Our goal, more fully stated below, was to begin a process of analysis and data release which, with appropriate feedback, will allow us to develop a more comprehensive understanding of the interrelationship between inpatient and outpatient care, and the cost and quality implications of an expanding universe of healthcare delivery options.

The word ambulatory refers to medical services provided outside of the inpatient hospital setting. It is often used synonymously with the word outpatient.

At this time, the Council's regulatory mandate is limited to ambulatory surgical procedures, and to a limited extent, information about diagnostic procedures. Those procedures make up the content of this report. By no means do they include the wide range of outpatient treatments and should not be interpreted as such.

This report begins with an overview of the ambulatory surgical data submitted to the Council and compares it to the same inpatient hospital procedures and treatment. In the same way that not all outpatient procedures and treatment are included, not all inpatient procedures are included: only those "collected" inpatient procedure codes that match the ambulatory procedure codes appear in this report.

A Focus on Ambulatory Surgery

Ambulatory surgery has been increasing in the United States since the early 1980's. The two major reasons for this increase are advances in medical technology and cost containment initiatives, such as changes in reimbursements. The medical advances include improvements in anesthesia, which enable patients to regain consciousness more quickly with fewer aftereffects, as well as more effective pain medications. In addition, minimally invasive and noninvasive procedures are being developed and performed with increasing frequency. Examples include laser surgery, laparoscopy, and endoscopy. These medical advances have made surgery less complex and risky.

At the same time, concern about rising health care costs led to changes in insurance plans that encouraged the development of ambulatory surgery. For example, in the early 1980's, Medicare was expanded to include care in ambulatory surgery centers, and a prospective payment system based on diagnosis-related groups (DRGs) was adopted for hospital inpatient care that created strong financial incentives for hospitals to shift less complex surgery to outpatient settings. Many state Medicaid plans and private insurers followed the lead of the Medicare program and adopted similar policies.

As these changes went into effect, many types of surgeries previously performed in hospitals and requiring overnight stays increasingly were performed during ambulatory visits. In addition, the number of freestanding ambulatory surgery centers nationally grew from 239 in 1983 to more than 1,800 in 1993.

As this shift from the inpatient to the outpatient setting occurs, the need for information increases. Those involved in health care purchasing, treatment and policy decisions want to understand the relationships between treatment that occurs in the outpatient and the inpatient setting. The increase in outpatient treatment has been seen as at least a partial cost containment measure; outpatient care involves a shorter period of hospitalization, no overnight stays, less resource allocation, and therefore, lower costs. In addition, advances in medical technology that have led to an increase in outpatient care should be reflected in better results for patients: procedures that are less invasive, and that involve less pain and recovery time and are equally as effective.

To date, however, little information has been available to purchasers, consumers, policy-makers and providers to assess whether these desired results are in fact occurring. Are costs being restrained as a result or are they merely being shifted? Is utilization changing, and how is it changing? Is patient care improving? Is greater value for the health care dollar being obtained?

This report presents some basic analyses of these data in order to begin to address some of these questions, provoke additional ones, and perhaps most importantly, to provide a common knowledge base of understanding about surgical procedures in the outpatient setting. As the Council continues to examine the various pieces that make up the health care delivery system, it can over time provide a unified database that will provide important information for those who purchase, consume, provide, manage and pay for health care in Pennsylvania. It can be a valuable resource for those making policy decisions about health care as well.

What is included in this report?

This report includes 492,090 procedures performed on patients in Pennsylvania hospitals, short stay units and freestanding ambulatory surgery facilities during the period January 1, 1996 through March 31, 1996. Of those, 267,307 (54%) were performed in an ambulatory setting and 224,783 (46%) were performed in an inpatient hospital basis.

It is important to note that this report does not cover all outpatient procedures or treatments. The data included derive from the principal procedure of collected ambulatory surgical procedures mandated by the Council under state law. The ambulatory principal procedure matches the principal procedure for the inpatient data. Additionally, the data do not include other procedures performed during the patient's hospital stay.

Two thousand and ten different procedures are collapsed into 16 primary body systems. Additional detail for each body system is provided in the tables in the rear of the report. For example, cardiac catheterizations are grouped under "Heart and Pericardium - Other Operations". Cataract operations are grouped under "Eye-Lens" procedure group. A listing of the included ICD.9 codes appears in Table 5 next to the procedure names.

Included in this report are counts of admissions, average age, percentage across body systems within the inpatient and outpatient setting, percentage across the facility setting (Inpatient/Outpatient) for respective body systems, and by region. The percentage of inpatient cases with an admission severity group score of greater than zero is also reported.

The severity information (ASG or Admission Severity Group) and age information are presented in order to better understand the relationship between the patients' level of illness or risk and the setting (inpatient vs. ambulatory) to which they are referred or admitted.