Reductions in unwanted complications and lengths of inpatient stay by use of "dynamic guidelines."

It has been noted by many authors that the elderly are more prone to developing unexpected comorbid events after elective surgeries than are younger patients. Most often, these unwanted complications are related to pulmonary, cardiovascular, renal-metabolic, or neurological events.

Additionally it has been reported that pathologic concurrent disorders are more important predictors than age, per se. Some significant predictors reported by investigators have been low FVCs, CO[.sub.2], retention, smoking, ventricular wall motion abnormalities, low LV ejection fractions, and poor general physical conditioning.[1-7]

Based on the use of data from several published papers on post-operative complications constituting more than 500 cases, a "morbidity risk profile" for elderly patients was compiled. This profile showed an occurrence of unexpected secondary complications at a rate of 46 percent in the elderly. The range of reported complications went from a low of 20 percent,[8] to a high of 59.

In order to make use of data to reduce unwanted comorbid events in the elderly, a "Dynamic Guideline" was developed. It was designed to identify patients "at risk" before they underwent elective surgeries, and to alter potential risk factors in the preoperative, intraoperative, and immediate postoperative periods.

Methodology

Using the six-month period before developing and using the Dynamic Guideline, all cases of elective surgery in a senior population for QualMed HMO in Pueblo and Colorado Springs, Colo., were set aside for later review. This patient population represented about 3,000 seniors. Using the literature for a search of common risk indicators, a profile of major contributing causes of unexpected postoperative complications was developed. From this list, five major areas were chosen to medically screen seniors before approval for elective surgery (see Table 1). All of these areas were determined to have potential for preoperative intervention in order to potentially reduce unwanted postsurgical comorbidity events. Aside from determinations of pre-existing pulmonary, cardiac, renalmetabolic, neurologic, and gastrointestinal conditions, physicians were asked to supply data on the patents' smoking habits and their current status on independent versus dependent living situations.

* Table 1. Common Risk Factors for Unexpected Postoperative Complications in
Seniors
* LV ejection fraction less than 35 percent
* MI in prior 6 months
* Poor genral physical condition
* History of CHF
* Ventricular wall motion abnormalities
* FVC less than 50 percent of predicted
* pCO2 over 45
* Smoker
* Pre-existing pulmonary disease
* Weight more than 150 percent above normal
Source: Nolan, T. "Surgery in the Elderly." Postgraduate Medicine 9(2):199,
Feb. 1992.

Smoking was felt to be a potentially significant risk factor, even in the short term, because of known complications associated with high carbon monoxide and hydrogen cyanide blood and tissue levels, as well as the vasoconstrictive and reduced pulmonary ciliary functions effects of nicotine.[9-10]

Upon receipt of the requested data, when any patients were felt to be "at risk" for comorbid events, certain requirements were presented to the surgeons and patients before surgery was approved (see Table 2). Along with these requirements, brief summaries of the literature were also supplied to the surgeons to held them understand the reasoning behind the approach.

* Table 2. Requirements Presented to Surgeons and Patients Before Approval of
Elective Surgeries
* If patient smokes, he or she MUST stop two weeks before surgery.
* Patients with underlying pulmonary problems are required to
have preoperative training for pulmonary toilet.
* If patient has any mild to moderate underlying medical problems,
the primary care physician must follow the patient while inpatient.
* For patients with severe pulmonary problems, in whom surgery is
critical, a pulmonologist or internist must follow the patient as an
inpatient.
* For patients with severe cardiac problems, in whom surgery is critical,
a cardiologist must follow the patient as an inpatient.

After several months of the physicians becoming acclimated, another six-month study was performed to evaluate whether the interventions had a positive impact by reducing unexpected postoperative complications.

Results

Because of growth of the HMO senior population, analysis was performed on the basis of "event per 1,000 seniors" so that the preintervention and postintervention periods could be compared. Since the HMO's signup policy for seniors is based on Medicare guidelines, no special "selection" occurred. In other words, selection of seniors into the HMO plan was the same before and after the study.

Charts from the control group and the postintervention group were gathered, and a formal analysis was performed. The two parameters measured were length of stay (LOS) in the hospital beyond the norms for nonseniors and occurrence of organ system complications that were "unexpected" in each group. To prevent bias in LOS, no changes were permitted in standard HMO LOS criteria or management of LOS days.

The control group was found to have an incidence of 45 percent of seniors with two or more LOS days beyond the norm, with 39 related to pulmonary complications (atelectasis causing hypoxia, acute bronchitis, and pneumonia). The LOS days beyond the norm per 1,000 seniors was 54 per 1,000.

The test group was found to have an incidence of 35 percent of seniors with two or more LOS days beyond the norm, with 25 related to the pulmonary complications defined above. The LOS days beyond the norm for the test group was 34 per 1,000, or a drop of 20 LOS days per 1,000.

Discussion

As a result of the use of Dynamic Guidelines and preoperative interventions for seniors, significant reductions in unexpected LOS days were obtained. The effect was 25 percent reduction in LOS days (p = .0110).

A significant reduction in pulmonary complications postoperatively explained the major portion of the decrease in LOS days (p = .1038). There were no significant changes in cardiac, renal-metabolic, neurologic, or gastrointestinal events, although there was a slight nonstatistical reduction (8 percent) in cardiac events (p = .2514). Table 3 outlines the change in complication rates from the control group to the test group.

[TABULAR DATA OMITTED]

It appears that the current literature may be used as a basis to develop Dynamic Guidelines that will lead to better identification of risk levels before elective surgeries are approved and that will allow managed care systems to develop approaches to reduce the identified risk patterns that lead to unexpected and unwanted postoperative comorbid events.

From the perspective of the HMO, this results in better quality of care (less morbidity) and less utilization of potentially preventable extra hospital days.

Because of the success of this approach, the methodology has been extended to all HMO patients who have identifiable preoperative risks. Other "risk" identifiers are being researched in an attempt to further reduce these complications.

References

[1.] Nolan, T. "Surgery in the Elderly." Postgraduate Medicine 91(2):199-202, 205-8, Feb. 1992. [2.] Seymour, D. and Vaz, F. "A Prospective Study of Elderly General Surgical Patients: II. Postoperative Complications." Age Aging 18(5):316-26, Sept. 1989. [3.] Keating, H. "Major Surgery in Nursing Home Patients." Journal of the American Geriatric Society (JAMS) 40(1):8-11, Jan. 1992. [4.] Williams-Russo, P., and others. "Post-Operative Delirium: Predictors and Prognosis in Elderly Orthopedic Patients." JAMS 40(2):759-67, Aug, 1992. [5.] Watters, J. "Preventive Measures in the Elderly Surgical Patient." Canadian Journal of Surgery 34(6):561-4, Dec. 1991. [6.] Johnson, J. "Surgical Assessment in the Elderly." Geriatrics 43(Suppl):83-90, Dec. 1988. [7.] Dales, R., and others. "Preoperative Prediction of Pulmonary Complications Following Thoracic Surgery." 104(1):155-9, July 1993. [8.] Margiotta, S., and others. "Cholecystectomy in the Elderly." American Surgery 54(1):34-9, Jan. 1988. [9.] Silverstein, P. "Smoking and Wound Healing." American Journal of Medicine 93(1A):225-45, July 15, 1992. [10.] Munday, I., and others. "The Effectiveness of Pre-Operative Advice to Stop Smoking." Anesthesia 48(9):816-8, Sept. 1993.