Ambulatory Parathyroidectomy for Secondary Hyperparathyroidism at a Large Dialysis Program in Toronto: A Program Report

What was known before

The prevalence of chronic kidney disease (CKD) in Canada is expected to rise with an aging and growing population coupled with rising rates of diabetes, hypertension, and cardiovascular disease. The burden of CKD on patient outcomes and the overall health care system continues to rise. The cost of providing hemodialysis at a tertiary center or outpatient facility in Canada is more than $60,000 CAD per patient per year. ¹ Patients with kidney disease often require multidisciplinary care with close coordination between multiple care providers. This is equally important in the care of patients treated with KRT and secondary hyperparathyroidism (sHPT). It is common finding within this vulnerable population occurring at about 30% to 50% among prevalent patients. ² In addition, sHPT can present early during the course of progressive CKD with parathyroid hormone (PTH) levels becoming elevated often before abnormalities in serum calcium or phosphate are detected. This leads to abnormalities of bone mineral density being present often before dialysis therapy is initiated. ³ Traditionally, it was believed that sHPT was limited to the skeletal system leading to extreme variations in bone turnover disease, but more contemporary data have revealed that other processes including vascular calcification, calciphylaxis, and neurologic disturbances can also occur. ³ Therefore, in the absence of timely treatment, sHPT can result in decreased quality of life and increased mortality.^4,5 Novel agents, specifically calcimimetics, have certainly revolutionized the care of patients and creating a shift in the treatment of sHPT away from surgical management. ⁶ Despite the overwhelming success and effectiveness of calcimimetics, approximately 38% of patients will be refractory to medical treatment and need surgical intervention to control disease.^7,8

Parathyroidectomy within this population is best performed by specialists, such as endocrine surgeons, requiring operative care in specialized centers. Unfortunately, these procedures cannot be performed as day surgeries and require close post operative monitoring, as patients are at risk for severe hypocalcemia. ⁹ For this reason, although there is no American Society of Anesthesiogists (ASA) cut off for patients eligible to receive surgery at the site, parathyroidectomy for patients with sHPT were not performed at the WCH as it is an ambulatory surgical center without inpatient surgical beds.

Currently, patients are admitted postoperatively at their surgical site and dependent on levels of hypocalcemia have a length of stay which ranges from 2 days to 2 weeks. The constraints of the health care system as it relates to acute care beds has been a prevalent concern that predated the pandemic. For example, data from the Organisation for Economic Co-operation and Development^10,11 (OECD) shows that Canada has 1.9 acute care beds for every 1000 people. These constraints were amplified with the pandemic and as a result many “lower” priority surgical cases were deferred. ¹² Surgical procedures are prioritized by pathology, with preference being given to oncology procedures. ¹³ Consequently, patients with sHPT requiring parathyroidectomy are often placed on ever increasing surgical waitlists. The average wait time for parathyroidectomy in the province is up to 209 days for surgery with only 60% of patients receiving surgery within the target timeframe. Target surgical timeframe does vary based upon the designated patient priority but ranges from 56 to 182 days. Target wait times are Provincially dictated and are identical for each center. These procedures occur mostly in select academic centers due to the specialized training required. Stratified by center patient’s receiving surgery by target time frame varies across the province of Ontario with 17% at London Health Sciences Centre, 49% in Hamilton’s St. Joseph’s Health Care System, 50% at Toronto East Health Network, 67% at St. Michael’s Hospital and 89% in the Sinai Health System in Toronto. ¹⁴

This data reflects primary, secondary, and tertiary hyperparathyroidism as a surgical indication. ¹⁴ As such, the actual wait time for patients with secondary disease—due to their medical and surgical complexity necessitating inpatient care in specialized centers—is substantially higher with patients sometimes needing to be referred between surgeons to expedite care. The health care system is expected to do more with less and this had been exacerbated in the height of the COVID-19 pandemic. This was the primary catalyst for our program to expedite patient access to surgery and prevent some of the aforementioned complications related to uncontrolled sHPT.

Consequences of uncontrolled sHPT pose a considerable threat to patients’ overall health and quality of life. Cardiovascular risk is increased, as is the risk for fractures regardless of age, and severe and disabling pruritus can develop.^15-17

Patients on dialysis have long-term therapeutic relationships with their care team. ¹⁸ In adding them into the circle of care early on after surgery patient treatments can be individualized according to their needs rather than using a one size fits all approach at a center not familiar to them. Enabling continued care by the patient’s primary team, in close communication with the surgical team.

What this adds

A coordinated care model where parathyroidectomy can be performed in an outpatient surgical setting with subsequent post operative transfer of care to the patients’ primary Nephrology team will allow for increased access to parathyroidectomy, enhanced continuity of care, and better management of postoperative hypocalcemia. The model will not only improve patient outcomes by decreasing the complications of uncontrolled hyperparathyroidism and postoperative hypocalcemia but will also result in cost savings by decreasing the overall length of patient admissions and reducing duplication of care services.

Current State of the Program

To address this gap in patient care, a collaborative effort between the Endocrine Surgery team at the Women’s College Hospital and the Nephrology team at Sunnybrook Hospital has created an ambulatory parathyroidectomy program for patients with sHPT. Under this program, patients receive their surgical care at the Women’s College and after an appropriate period of post operative monitoring, are transferred that same day to the hospital associated with their primary dialysis site.

Patients who have failed medical management for sHPT requiring parathyroidectomy are reviewed monthly by the Nephrology and Endocrine Surgery team. From these patients, those whose co-morbidities would allow for safe surgical treatment at an ambulatory surgery site, without onsite intensive care teams, are selected based on the American Society of Anesthesiology (ASA) classification. ¹⁹ Appropriate patients are then booked for surgery with coordination between both sites’ physicians, nursing, and transport teams.

On the day of procedure, patients are booked as the first case of the day to reduce likelihood of delay and facilitate transfer. Postprocedure, the patient is monitored at the surgical site for 6 hours and then transferred to the home dialysis site if there are no signs of bleeding. Postoperative bleeding is one of the most concerning complications that can occur after surgery in the neck due to the risk of airway compromise. For thyroid surgery, it has been established that post operative bleeding requiring intervention is most likely to occur within 6 hours postoperatively and accordingly, this timing was chosen for monitoring. ²⁰

Once transferred, under the care of their primary Nephrologist, the patient is monitored, undergoes their routine dialysis, and is discharged when biochemically stable. If surgical concerns arise the surgical team from the WCH will assess the patient. Patients with sHPT are at risk of hypocalcemia postoperatively due to hungry bone syndrome. ²¹ Severe hypocalcemia can be life-threatening, with symptoms of tetany, seizures, and cardiac arrhythmias. ²¹ For this reason, a standardized monitoring protocol of scheduled calcium levels as well as a treatment algorithm were developed to be implemented postoperatively. It is anticipated that this protocol will lead to improved management of calcium levels, prevent episodes of symptomatic hypocalcemia and decrease requirements for IV calcium. The post operative care plan is further outlined in Figure 1.

OPEN IN VIEWER

Figure 1.

Post-parathyroidectomy care plan.

A single case has been performed as a pilot assessment. Subtotal parathyroidectomy was completed at the WCH as an outpatient surgical procedure for a patient with sHPT on KRT on hemodialysis for 5 years. The patient was monitored, and post operative medications initiated as outlined in Figure 1. Initial PTH as assessed in the recovery unit was 12.4 from a preoperative level of 294 pmol/L and is 2.3 pmol/L at 1 month follow-up. The patient was transferred to Sunnybrook hospital, her home dialysis site, after satisfactory 6-hour postsurgical assessment by the surgical team. On post operative day 1, the patient required initiation of IV calcium replacement which was weaned as her oral calcium and calcitriol doses were increased. The patient was then discharged home with stable calcium levels on an oral replacement regimen at post operative day 7.

Discussion: Strengths, Limitations, and Future Directions

While greatly improving patient access to care, the required co-ordination between sites can be seen as a limitation for the ambulatory parathyroidectomy program. It is anticipated, however, that while the time investment in coordinating resources may be considerable initially, this demand will decrease over time as involved teams are familiarized with the process.

Another potential limitation is that resources in terms of the home dialysis facility bed and OR time at the ambulatory surgical site are both lost if a case must be canceled. That said, careful patient selection with regards to ASA can minimize any medical causes for cancelation. Unforeseeable events can and do occur, but we anticipate that such occurrences will be rare, and we believe that the benefit of improved access to care far outweighs this risk.

The program was successfully launched in September 2021, with the performance of our first ambulatory parathyroidectomy. Future procedures are planned in the upcoming weeks and months and the team is looking to expand and include other regional hospitals to expedite the availability of parathyroidectomy for appropriate patients in these centers.

In applying the principles of quality improvement methodology, we hope that our primary outcome measure of interest is a reduction in wait time to surgery through this collaborative model. Other important measures that we will consider as part of an ongoing evaluation of this initiative which will be part of future publication is to describe balancing measures such as overall changes in parathyroidectomy rates and timing post program institution, a 30-day hospitalizations postsurgery and patient satisfaction.

Conclusion

Our health care system like many others around the world must continue to provide optimal and timely care in the face of rising costs coupled with resource constraints. Innovative and collaborative models of care are needed to meet these current and future challenges. We describe the collaborative efforts between two large, specialized centers in Toronto, Canada, in bridging current gaps in access to timely parathyroidectomies for patients on dialysis. Programs should leverage their strengths and expertise in collaborating to meet the demands of our evolving health care system. In adopting ambulatory parathyroidectomy program, we will improve patient access to care but ongoing cost evaluation of this program to ensure sustainability and replicability will be needed.