A population study in the Province of Ontario of the complications after conversion of hip or knee arthrodesis to total joint replacement.

OBJECTIVE: To evaluate the complication rates after conversion of hip and knee fusions to total joint replacements in the Province of Ontario. DESIGN: A retrospective cohort study. PATIENTS: Those who had undergone an elective conversion of a hip or knee fusion to a total joint replacement during fiscal year 1993 through 1996, as captured in the Canadian Institute for Health Information and Ontario Health Insurance Plan databases. OUTCOME MEASURES: Inhospital complications and length of initial hospital stay, revision, infection, amputation and repeat fusion rates within 4 years. RESULTS: Conversion of hip and knee fusion to total joint arthroplasty was generally performed by high-volume surgeons in high-volume hospital settings. Forty hip and 18 knee replacements involved conversion of a previous fusion. Conversion of a hip fusion was associated with a 10% infection rate, a 10% revision rate and a 5% resection arthroplasty rate due to infection within 4 years of the conversion. Conversion of a knee fusion was associated with an 11% infection rate, and a more than 5% revision rate at 4 years. Over 16% of patients who underwent conversion of a knee fusion required removal of the components (for various reasons) within the first 4 years. CONCLUSIONS: There is a high rate of complications after conversion of a hip or knee fusion to a total joint arthroplasty. These issues must be carefully considered and discussed with the patient before any conversion procedure.

Are complication rates for elective primary total hip arthroplasty in Ontario related to surgeon and hospital volumes? A preliminary investigation.

OBJECTIVE: To test the hypothesis that complication rates for elective total hip replacement operations are related to surgeon and hospital volumes. DESIGN: Retrospective population cohort study. STUDY COHORT: Patients who had undergone elective total hip replacement in Ontario during 1992 as captured in the Canadian Institute for Health Information database. MAIN OUTCOME MEASURES: In-hospital complications, 1- and 3-year revision rates, 1- and 3-year infection rates, length of hospital stay, and 3-month and 1-year death rates. RESULTS: Surgeons with patient volumes above the 80th percentile (more than 27 hip replacements annually) discharged patients approximately 2.4 days earlier (p < 0.05) than surgeons with volumes below the 40th percentile (less than 9 hip replacements annually) even after adjusting for discharge disposition, hospital volume, patient age, sex, comorbidity and diagnosis. Complication rates requiring hospital readmission and death rates did not differ by surgeon or hospital volume (p > 0.05). CONCLUSIONS: There is no evidence to support regionalization of elective hip replacement surgery in Ontario based on adverse clinical outcomes. Surgeons who perform a large number of total hip replacements are discharging patients earlier than less experienced surgeons, without any-demonstrable increase in complications leading to hospital readmission. The explanation for this observation remains unknown and will require further study.

Hospitalizations for back and neck problems: a comparison between the Province of Ontario and Washington State.

OBJECTIVE: To examine back and neck hospitalizations in the Province of Ontario and Washington State. Because of their different organization and financing, there has been considerable interest in comparing healthcare systems in Canada and the United States. Features of healthcare systems might be expected to result in greater variations in care for elective than urgent conditions. DATA SOURCE: Automated hospital discharge databases. STUDY DESIGN: Previously developed algorithms were used to identify surgical and nonsurgical hospitalizations for back and neck problems in the administrative databases. We compared overall rates of hospitalization and lengths of hospital stay in Ontario and Washington as well as small area variations within the province and state. PRINCIPAL FINDINGS: Surgical back and neck hospitalizations were three times as common in Washington, but medical hospitalizations were twice as common in Ontario. Provincial lengths of stay were longer for both surgical and nonsurgical hospitalizations. Admission rates varied substantially and significantly among small areas in both Washington and Ontario. Variations in hospital length of stay were greater in Ontario, particularly for nonsurgical back and neck hospitalizations. CONCLUSION: The two jurisdictions had very different patterns of hospital utilization for one of the most common health problems seen by physicians. Our results suggest that the global controls on hospital budgets and access to technology in Ontario were associated with lower rates of surgery, higher rates of hospital-based medical care, and longer lengths of stay. They also indicate that the utilization review process in Washington was associated with lower small area variation rates for medical back care.

Use of selective serotonin-reuptake inhibitors or tricyclic antidepressants and risk of hip fractures in elderly people.

BACKGROUND: Tricyclic antidepressants (TCAs) are associated with an increased risk of falls and hip fractures in elderly people. Selective serotonin-reuptake inhibitors (SSRIs) are reported to be better tolerated than TCAs. We investigated the risk of hip fractures associated with SSRIs and TCAs. METHODS: This case-control study used administrative healthcare data from the province of Ontario, Canada. 8239 cases-patients aged 66 years or older, treated in hospital between April, 1994, and March, 1995, for hip fracture-were each matched for age and sex to five controls. Logistic regression was used to calculate the odds ratio for hip fracture with adjustment for potential confounding effects produced by concomitant drug use and comorbidity. FINDINGS: With participants who had no exposure to antidepressants as the reference category, the adjusted odds ratio for hip fracture was 2.4 (95% CI 2.0-2.7) for exposure to SSRIs, 2.2 (1.8-2.8) for exposure to secondary-amine TCAs, and 1.5 (1.3-1.7) for exposure to tertiary-amine TCAs. For all types of antidepressants, current use was associated with a higher risk of hip fracture than former use. The odds ratios for hip fracture were higher for new current users than for continuous current users in all three drug classes. The proportion of current use in the low-dose range was 22% for SSRIs, 50% for secondary-amine TCAs, and 58% for tertiary-amine TCAs. INTERPRETATION: Exposure to any of the three classes of antidepressants is associated with a significant increase in the risk of hip fracture. Despite differences in dose distribution, this analysis suggests that SSRIs do not offer an advantage over TCAs in terms of risk of hip fracture.

Trends in hospital use for mechanical neck and back problems in Ontario and the United States: discretionary care in different health care systems.

OBJECTIVE: To describe and compare trends in hospital admission rates for mechanical neck and back problems between 1982 and 1992 in Ontario and the United States. DESIGN: A descriptive analysis of hospital admissions, with data for Ontario extracted from the Canadian Institute for Health Information database and data for the US extracted from the National Hospital Discharge Survey. SETTING: All acute care hospitals in Ontario and a probability sample of acute care hospitals in the US. PATIENTS: Adults aged 20 years or more who were admitted to an acute care hospital for mechanical neck or back problems in 1982, 1987 or 1992. Mechanical neck and back problems were defined using an algorithm developed by the study team. OUTCOME MEASURE: Hospital admission rate per 100,000 adults. RESULTS: Between 1982 and 1992 the hospital admission rate for medically treated cases decreased by 52% in Ontario and by 75% in the US. Over the same period the admission rate for surgically treated cases increased by 14% and by 35% respectively. By 1992 the admission rate for medically treated cases in the US was 23% higher than that in Ontario, whereas the rate for surgically treated cases was 164% higher. CONCLUSIONS: The hospital-based medical or surgical treatment of mechanical neck and back problems provides an example of discretionary care. The higher admission rates for surgery in the US may reflect a larger supply of surgical specialists and imaging units. Further work is needed to confirm these findings for other types of discretionary care and to compare the appropriateness of care and clinical outcomes for discretionary care in these 2 jurisdictions.

A population-based study of reoperations after back surgery.

STUDY DESIGN: Longitudinal follow-up study of back surgery reoperations using an administrative database. OBJECTIVES: To identify population-based rates and factors that determine the need for reoperation after back surgery. SUMMARY OF BACKGROUND DATA: Reoperation after lumbar surgery has poorer results than the initial surgery, yet the population-based incidence and determinants of reoperation are not known. Reported rates of reoperation are derived from retrospective case series and range from 4% to 15%. There are conflicting data on the rate of reoperation after different types of initial surgery. METHODS: All patients who had back surgery in the Province of Ontario (population 10,000,000) between April 1990 and March 1991 were identified using hospital discharge abstracts and an ICD-9 code algorithm. Patients who had undergone prior surgery were excluded. Patients were observed from the index operation to subsequent readmission and reoperation with a maximal time to follow-up examination of 4 years. Basic demographic information and information regarding diagnoses, surgery performed, complications, comorbid factors, reoperation diagnosis, and surgery type were obtained. Patients were divided into surgical treatment groups, and their subsequent reoperations were identified. Multivariate analysis using proportional hazards modeling was conducted. RESULTS: The index surgery group consisted of 4,722 patients, of whom 449 (9.5%) underwent reoperations in the follow-up period. Complications from surgery were significantly higher in the fusion and fusion with decompression groups. The reoperation rate was not significantly different among individual surgery groups. Diagnosis, operation performed, complications after the index surgery, comorbid conditions, and sex did not predict the need for spine reoperation. Younger age was predictive of the likelihood of reoperation (P = 0.04) CONCLUSION: The incidence of reoperation after back surgery is independent of diagnosis and type of surgery performed. Despite different anatomic reasons for surgical intervention, the success of different types of surgery are not influenced by the factors identified in this study. More extensive surgery does not prevent nor predispose a patient to the need for further surgery.

A survey of red cell use in 45 hospitals in central Ontario, Canada.

BACKGROUND: The purpose of this survey was to establish baseline information on blood component use in relation to patient diagnoses, procedures, and demographics and to identify patterns of blood use that may be used for blood program planning and transfusion audits. STUDY DESIGN AND METHODS: A cross-sectional survey of the transfusion of blood components in teaching and nonteaching hospitals in central Ontario between September 1991 and August 1992 was carried out. Coders of hospital medical records routinely record demographics, procedures, diagnoses, and other relevant information. A protocol was created by which medical records coders could add the components transfused to the discharge abstract for this study. Red cell use is reported here. RESULTS: Of the 61 hospitals invited to participate, from which 547,279 patients were discharged during the 12-month period of the study, 45 (74%) agreed to participate. Information was collected on 439,373 discharged patients. Of these, 26,611 (6.1%) received at least 1 unit of red cells. Of a total of 101,116 red cell units transfused, more than 74 percent were used in patients discharged with neoplasms, gastrointestinal diseases, circulatory system diseases, and trauma. High-transfusion-use procedures included operations and procedures on the digestive and cardiovascular systems, diagnostic and therapeutic procedures, musculoskeletal system, and hemic or lymphatic system procedures. CONCLUSION: This survey provides baseline blood transfusion information for a specific period that can help determine the need for hospital audits and maximum surgical blood-order schedule guideline reviews. This information is relevant to current recommendations to reduce patient's exposure to blood components. These transfusion data will assist in blood program planning based on known disease trends, demographics, and population changes.