BOSTON – Preoperative comorbidities and postoperative complications are the most common reasons that patients are readmitted to a hospital within 30 days of thyroid or parathyroid surgery, but outpatient surgery was associated with a lower likelihood of readmission, investigators have found.
A review of data on more than 7,000 patients who underwent cervical endocrine resections showed that 4% were readmitted within a month of surgery, reported Dr. Matthew G. Mullen, a surgery resident at the University of Virginia Health System in Charlottesville.
"Identifying best practice patterns to avoid major postoperative complications will help reduce hospital readmission rates and improve the quality of patient care," Dr. Mullen said at the annual meeting of the American Association of Endocrine Surgeons.
Previous single-institution studies have shown readmission rates for patients undergoing thyroidectomy of 0.3%-3.9%. A 2010 study of readmission rates among elderly patients undergoing thyroidectomy for thyroid cancer found that 8% required readmission within a month of surgery, Dr. Mullen noted.
To see whether, as they suspected, patients with more medical comorbidities and postoperative complications are more likely to be back in the hospital within 30 days of surgery, the investigators reviewed the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) participant use data file, which includes records on 442,149 elective surgery cases from 315 U.S. hospitals. Data on a total of 7,069 total elective cases, including 3,711 thyroidectomies and 3,358 parathyroidectomies were reviewed.
They found an overall readmission rate of 4.0%, with a rate of 4.1% for patients undergoing thyroidectomy, and 3.8% for those undergoing parathyroidectomy.
Demographic factors significantly associated with a greater likelihood of readmission included diabetes (present in 18.6% of readmitted patients, vs. 12.5% of not readmitted patients; P = .003), severe chronic obstructive pulmonary disease (4.6% vs. 2.0%; P = .002), hemodialysis (11.8% vs. 2.2%; P = .001), and weight loss of more than 10% (1.8% vs. 0.5%; P = .005). Younger and heavier patients were more likely to be readmitted within 30 days than were slightly older and lighter-weight patients.
Complications predict readmission
Postoperative complications associated with readmission included wound complications (5% vs. 0.3%; P less than .001 for all following comparisons, unless noted), respiratory complications 5.4 vs. 0.2%), renal complications (2.1% vs. 0.3%), neurologic complications (0.7% vs. 0.1%; P = .008), and cardiovascular complications (4.6% vs. 0.2%).
In multivariate analysis, factors that were significantly associated with readmission were reoperation within 30 days (P less than .001), American Society of Anesthesiologists physical status class (P = .024), patient functional status (independent vs. partially or fully dependent, P = .007), renal insufficiency (P = .004), and hemodialysis (P = .005).
In contrast, patients who were discharged within 24 hours of surgery were significantly less likely to be readmitted (odds ratio, 0.63; P = .006).
The researchers also found that 63% of patients had a longer than 24-hour stay after surgery – a finding that Dr. Mullen said was surprising – and that patients undergoing surgery for malignant disease were significantly more likely to be readmitted than were patients with benign disease (11% vs. 2.6%, P less than .001). There was no difference in readmission rates of patients treated by general surgeons, compared with those treated by surgeons trained in otolaryngologic procedures.
Dr. Mullen noted that the study was limited by the lack of data on the reasons for each readmission and by a lack of information on many complications that are specific to endocrine surgery.
In the discussion, Dr. Samuel K. Snyder of Texas A & M University in Temple, commented on the lack of study specifics about the reasons for readmission making it hard to draw conclusions about how best to prevent readmissions.
Dr. Mullen responded that because some of the patients had treatable comorbidities such as renal insufficiency, medical augmentation could be a reasonable approach to reducing postoperative complications and risk of readmission.
The authors did not disclose the study funding source. Dr. Mullen and Dr. Snyder reported having no financial disclosures.