The safety of foot and ankle procedures at an ambulatory surgery center

Abstract

Background

This study evaluates the safety of foot and ankle outpatient surgeries at a freestanding ambulatory surgery centers.

Methods

A total of 1352 cases were evaluated for adverse events in a retrospective review of all foot and ankle cases performed over a 5-year period at a single center.

Results

The rate of adverse events was 2.3%, with 31 identified over the 5-year period (23 infections, 5 symptomatic thromboembolisms, 3 postoperative hospital transfers).

Discussion

The rate of postoperative adverse events in outpatient foot and ankle procedures is low. These surgeries can be performed safely in an outpatient setting at an ASC.

Level of evidence

Level IV, Case Series.

1. Introduction

Outpatient surgery at ambulatory surgery centers (ASC) is becoming increasingly common. There are now over 5400 ASCs in operation in the United States, and nearly two-thirds of all surgeries are performed on an outpatient basis.^1,2 ASCs are defined as facilities that provide surgical services to patients that do not require hospitalization postoperatively.³ ASCs have been shown to provide significant cost savings and improved efficiency when compared to hospitals.^4,5 There has been a continued trend toward performing more surgeries on an outpatient basis; in 2018, the Center for Medicare and Medicaid Services even placed total knee arthroplasty on the outpatient fee schedule.⁶ With an increase in the number and type of surgeries performed at ASCs, the safety of these facilities needs to be examined.

Morbidity and readmission after open reduction and internal fixation of ankle fractures have been evaluated using the American College of Surgeons National Surgical Quality Improvement Program. In this study, of the 4412 patients identified, 5% had an adverse event.⁷ These patients were not stratified according to outpatient versus inpatient status. In a separate study of ankle fractures also not stratified according to inpatient versus outpatient status, 5.1% of patients had a complication.⁸ Total ankle arthroplasty performed in an outpatient setting has previously been found to have a 15.4% complication rate.⁹ To date, there do not appear to be any studies that have evaluated the safety of foot and ankle procedures performed purely on an outpatient basis at an ASC.

In 2016, the safety of upper extremity surgeries performed at an ASC was evaluated. A low adverse event rate of 0.20% was found among their cohort of patients.¹⁰ Foot and ankle surgeries provide unique challenges to postoperative care. Weight-bearing restrictions after foot and ankle surgery limit a patient's ability to ambulate, which can contribute to increased thromboembolism risk. When compared to other elective orthopedic procedures, surgeries performed on the foot and ankle are known to have a higher rate of surgical site infections.¹¹ The purpose of this study is to determine the adverse event rate in outpatient foot and ankle surgeries performed at an ASC.

2. Methods

After obtaining IRB approval, a retrospective review of all foot and ankle cases performed at a single ASC were reviewed over a 5-year period (2010–2015). The surgeries were performed by 3 board-certified orthopedic surgeons, 1 of whom was subspecialty certified in foot and ankle surgery. Preoperative clearance was obtained from the patients' primary care physician or cardiologist, if determined to be necessary while taking the patients’ history. The anesthesiologist, in conjunction with the treating surgeon, determined if each surgery could be performed at the ASC without undue risk to the patient, or whether the case needed to be performed at a hospital. Patients that were classified as American Society of Anesthesiologists physical status level 3 or 4 could not have their surgery performed at the ASC.

Included in our study were 1352 foot and ankle surgeries. We utilized adverse event criteria from prior ASC literature during our analysis, separated into 7 categories: (1) acute infection requiring IV antibiotics or return to the operating room for irrigation and debridement, (2) postoperative transfer to a hospital, (3) wrong-site surgical procedure, (4) retention of a foreign object, (5) postoperative symptomatic thromboembolism, (6) medication error, and (7) bleeding complications. Each adverse event was evaluated to determine if further workup and treatment was needed, and if any patient sustained permanent morbidity. Patients with open wounds and surgeries that were performed for the purpose of clearing an infection not related to the index procedure were excluded. A total of 48 planned foot and ankle surgeries were cancelled the day of surgery. As part of our analysis, we also examined the cause of each cancellation with the goal of developing strategies to reduce these incidents.

3. Results

3.1. Cancelled cases

Over the 5-year period of the study, 1400 foot and ankle cases were scheduled. A total of 48 (3.4%) cases were cancelled the day of surgery in the preoperative holding area. Of these cancellations, 18 (37.5%) were for transportation-related issues (e.g., the patient had no ride home set up following the completion of surgery); 14 (29%) were cancelled due to either hypertensive crisis or hyperglycemic episode; 4 (8%) were cancelled because the surgeon believed the surgery was no longer needed; 3 (6%) were cancelled due to protocol breach (e.g., the patient eating or drinking the morning of surgery); 2 (4%) were cancelled for nausea and vomiting; 2 (4%) had a rash near the operative site, and 1 case (2%) was cancelled for each of the following reasons: stroke, neck swelling, upper respiratory illness, urinary tract infection, or the patient was currently hospitalized. Table 1 summarizes the cancellations.

Table 1.

Summary of cancellations.

Cancellations	48
Transportation	18
Hypertension or hyperglycemia	14
Surgery no longer needed	4
Protocol breach	3
Nausea or vomiting	2
Rash	2
Stroke	1
Neck swelling	1
URI	1
UTI	1
Patient hospitalized	1

3.2. Adverse events

Of the 1352 foot and ankle cases analyzed, there were 31 adverse event occurrences, for a rate of 2.3%. The majority of adverse events were infections, with 23 occurring during the 5-year span. There were 5 symptomatic thromboembolisms and 3 postoperative transfers to a hospital during the study period. Table 2 summarizes the adverse events.

Table 2.

Summary of adverse events.

Adverse events	31
Infection	23
Thromboembolism	5
Postoperative transfer to hospital	3

3.3. Infection

Twenty-three patients sustained an infection, which corresponded to a rate of 1.7%. Diabetes was a comorbidity in 48% of patients who had an infection. Of these patients, 10 underwent a single irrigation and debridement in the operating room, and 13 were admitted to the hospital for IV antibiotics. All infections were successfully eradicated, and no repeat trips to the operating room or readmissions during our study period were required for further infection treatment.

3.4. Bleeding complications

There were no bleeding complications during the study period. Meticulous hemostasis was achieved at the end of each case, followed by tight, layered incision closure.

3.5. Postoperative symptomatic thromboembolism

A symptomatic thromboembolism was sustained by 5 patients, for a rate of 0.37%. The case mix for this complication included two Haglund's deformity corrections, a subtalar arthrodesis, a calcaneal slide osteotomy to correct hindfoot valgus, and a first metatarsal phalangeal joint arthrodesis. Of these patients, 4 sustained a deep vein thrombosis between 3 weeks and 5 months postoperatively. All clots occurred in the operative extremity. One patient had a history of oral contraceptive use. No other predisposing factors were identified. A separate patient sustained a pulmonary embolism 1 month after a Haglund's deformity correction. Although the patient's brother had died of a pulmonary embolism, the patient had no personal history of thromboembolism. All patients were placed on a prolonged course of anticoagulation and made a full recovery with no known repeat thromboembolic events.

3.6. Retention of a foreign object

There were no retained foreign objects during the study period. Standard counts of both sponges and sharps are performed by the circulating nurse and surgical tech at the time of closure.

3.7. Medication error

There were no medication errors. Allergies are reviewed with the patient in the preoperative holding area, and again at the preoperative timeout performed prior to the patient being placed under anesthesia.

3.8. Wrong-site surgical procedure

There were no wrong site surgeries during the study period. The surgical site is signed in the preoperative holding area by the attending surgeon or resident. The correct surgical site is again identified with the patient at the preoperative timeout prior to placing the patient under anesthesia in the operating room. Final confirmation of the surgical site is performed by the surgeon prior to making a skin incision.

3.9. Postoperative transfer to a hospital

There were 3 postoperative transfers to a hospital, for a rate of 0.22%. All 3 patients were transferred for further pain management. Two of these patients had incomplete blocks and the other refused both a pre- and postoperative block. One patient had a history of poorly controlled pain after surgery, but did not have a diagnosis of chronic pain. All 3 patients were discharged by postoperative day 2 and recovered uneventfully.

4. Discussion

Rising healthcare costs have led to an increased emphasis on quality of care and cost savings. Significant evidence suggests that ambulatory surgery centers provide an avenue for cost savings and efficiency without compromising quality. Day surgeries performed at an ASC, when compared to surgeries performed at a university hospital, have been shown to have cost savings from 17% to 43%, primarily derived from time-related expenditures in the operating room.⁵ In 2018, it was shown that supracondylar humerus fractures in a pediatric population treated at an ASC had equivalent outcomes as patients whose surgery was performed at a hospital, but with the added benefit of shorter surgical time and lower total charges.¹² A retrospective review of upper extremity procedures performed at an ASC in 2016 found a very low adverse event rate of 0.20%.¹⁰ The safety of ASC's need to be continually assessed as more procedures are performed at these facilities, including procedures within foot and ankle surgery, as this area has an increased risk of adverse events.

Foot and ankle surgery is known to have higher infection rates compared with other regions of the body, such as the upper extremity.¹¹ Documented infection rates for foot and ankle surgery range from 0.39% to 4.8%.13, 14, 15, 16 Our rate of 1.7% falls well within this spectrum. Nearly half of our patients who sustained an adverse event had a history of diabetes, which is a known risk factor for infection. A standard dose of preoperative antibiotics is given to all patients within 1 h prior to skin incision. No unique infection control practices are employed by our institution. Compared to prior literature, foot and ankle surgery performed at our ASC did not place patients at increased risk for an adverse infectious event.

Our rate of symptomatic thromboembolism was 0.37%, which is lower than reported in prior literature. The reported incidence of venous thromboembolic disease after foot and ankle surgery ranges from 0.79% to 4%.^17,18 We do not employ prophylactic anticoagulation postoperatively unless the patient is taking an anticoagulant for a medical comorbidity, in which case their prior medication is restarted postoperatively. Two prior studies have examined the use of a prophylactic anticoagulation in foot and ankle surgery, and no thromboembolism prevention benefit was identified.^19,20 Ambulatory surgery centers do allow for swift patient discharge and do not involve an inpatient stay, where there is potential for a patient to remain sedentary. These factors, along with a healthier patient population, could contribute to a lower rate of thromboembolism when foot and ankle surgeries are performed at an ASC.

Among our patients who required postoperative transfer to a hospital for admission, all 3 were transferred for inadequate pain control. Good pain control protocols, along with proper medical screening of patients, allowed us to achieve a low postoperative transfer rate of 0.22%. Our transfer rate compares favorably to a previously reported unanticipated admission rate of 3.3% among a group of Canadian patients undergoing outpatient foot and ankle surgery.²¹ Pain after foot and ankle surgery can be problematic. Procedures involving extensive bony work, such as hindfoot fusions and calcaneal osteotomies, are painful. Judicious use of regional anesthesia, along with setting proper patient expectations for postoperative pain, are critical to avoiding this type of adverse event. In patients with a history of poorly controlled postoperative pain or severe medical comorbidities, a hospital setting should still be considered for outpatient procedures should the need for admission arise.

Our study has some limitations. As with all ASCs, there is inherent selection bias within the patient population treated. Patients with severe medical problems are unable to have their surgery performed at an ASC, as the facility is not equipped to handle potential complications, which could have altered our adverse event rate. We only had access to patient medical records within our health system, so some adverse events may have been missed if a patient chose to utilize an outside health system. While surgery is never without risk, we deem our adverse event rate of 2.3% to be acceptable. With proper patient selection, outpatient foot and ankle surgery can be performed safely at ASCs.

Funding statement

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

Disclaimers

The views expressed in this article are those of the author(s) and do not necessarily reflect the official policy or position of the Department of the Navy, Department of Defense, or the United States Government. LCDR Cory Janney is a military service member (or employee of the U.S. Government). This work was prepared as part of his official duties. Title 17, USC, §105 provides that ‘Copyright protection under this title is not available for any work of the U.S. Government.’ Title 17, USC, §101 defines a U.S. Government work as a work prepared by a military service member or employee of the U.S. Government as part of that person's official duties.

Declaration of competing interest

Vinod Panchbhavi is a consultant for Stryker Orthopaedics as well as an editor for Lippincott Williams and Wilkins Publishing. The other authors have no declarations.