Case Review Study for Outpatient Oxford Knee Arthroplasty at Brandon Regional Health Centre. Riley Workman. ORNH Home for the Summer Program 2016

Transcription

1 Case Review Study for Outpatient Oxford Knee Arthroplasty at Brandon Regional Health Centre Riley Workman ORNH Home for the Summer Program 6 Brandon, Manitoba Supervisor: Dr. N. Klippenstein MD Considerations: Troy Smook, PA, Charles Bouchard (Zimmer Biomet)

2 Abstract The Oxford Knee Arthroplasty (OKA) is a procedure that involves replacing the components of the medical compartment of the knee to treat painful osteoarthritis and is a less invasive alternative to a Total Knee Arthroplasty (TKA) with a quicker recovery time. Currently, the Brandon Regional Health Centre (BRHC) has a clinical pathway that requires patients to be admitted to hospital for a minimum of one day post-operatively. This case review study was performed as a medical chart audit of OKA patients from January to February 6 to examine patient demographics, characteristics, details of the procedure, hospital course, details of discharge and emergency room visits (N=3, 6 from, 7 from 6) to determine the feasibility for the instalment of an outpatient OKA program. Data was retrieved using a standardized form filled out with information from the patient s medical charts. Results presented showed that patients were predominantly female (7%), from a rural location (7%) and aged 6-7 years (3%) who lived in a house or apartment with a spouse or other family members (8%). Most patients had a BMI over 3 kg/m (obese) and suffered from vascular and/or metabolic disease. Only surgical complications were experienced from patients giving pre-operative concern. In regards to hospital course, the majority of patients only remained in hospital for day (6%) with the most common complications experienced being extended bleeding from the surgical site, nausea and pain. Most patients received Tramacet, Hydromorphone or Ketorolac for pain control, Heparin for anti-coagulation prophylaxis and Dimenhydrinate for nausea. Urinary retention was the most common medical concern experienced in-hospital and none of the patients were able to mobilize independently with a walker or crutches on the same day of surgery, but all were able to before discharge. Only patient visited the emergency room shortly after discharge for a reason related to the surgery (pain and edema in leg), though a diagnosis of a deep vein thrombosis was dismissed by ultrasound. One patient returned for a revision of the Oxford knee to a TKA one year after the original Oxford knee procedure. The evidence provided suggests that an outpatient OKA program at BRHC is possible with some small changes in practice, as the current clinical pathway has shown strong success. If the recommendations presented in this report are explored and followed, the establishment of an outpatient OKA program at BRHC could be a successful, space and cost-saving endeavour for the hospital, and an excellent alternative for a better patient experience. Introduction The Oxford Knee Arthroplasty (OKA) is a unicompartmental arthroplasty that treats medial compartment osteoarthritis of the knee. Osteoarthritis occurs due to erosion of cartilage which leads to exposed bone-on-bone articulation and pain. Unlike Total Knee Arthroplasty (TKA), the Oxford Knee procedure involves replacing the medial compartment of the osteoarthritic knee while sparing the lateral compartment. In this manner, more of the normal tissue of the patient is

3 preserved. In order for the procedure to be indicated over a TKA, certain criteria must be met by the patient. Some of the indications/requirements for the Oxford procedure include severe pain, flexion deformity less than, radiographic signs that suggest bone-on-bone contact of the medial compartment and preservation of the cartilage in the lateral compartment, intra-articular varus deformity that is manually correctable at flexion, and an intact Anterior Cruciate Ligament (ACL). The Oxford Knee is a desirable procedure for patients as it is less invasive than a TKA, allows for a quicker recovery period for the patient including a shorter rehabilitation period and shorter hospital stay, movement feels more natural for the patient post-operatively and if it fails, or the lateral compartment becomes arthritic, the Oxford Knee can be revised to a TKA. At the Brandon Regional Health Centre (BRHC), a clinical pathway has been established for patients who undergo an OKA. The clinical pathway allows the physician to place standing orders for medications and other therapies before the surgery has begun. Guidelines are listed for the ward nurses and other disciplines in regards to patient care. Prior to the day surgery is scheduled, the patients are recommended to attend Pre-habilitation Clinic to assess their demographics, present medical condition and educate them on the surgery and their care postoperatively. To present day, each OKA patient is admitted to the ward with the expected stay of day. The operation is performed in the morning so that Physiotherapy (PT) and Occupational Therapy (OT) can see the patient on the same day as the operation, or Post-Operative Day # (POD#). During these visits, the patient s mobility and flexibility are assessed and questions are asked about the patient s current living situation. The purpose of the current study was to examine the feasibility of establishing an outpatient OKA program at BRHC. The manufacturer of the Oxford knee materials, Zimmer Biomet, has created an instructional course for orthopaedic surgeons that educates them on how the OKA can be an outpatient procedure. The instructional manual shows data from Drs. Keith and Michael Berend regarding the Oxford knee procedure and provides reasons for increased length of stay for patients and recommendations for establishing an outpatient program. Some of the recommendations include indications for proper patient selection, medications to use for satisfactory anaesthesia and pain control, post-operative care instructions and venous thromboembolic prophylactic measures. The present study was conducted to examine the clinical experiences of OKA patients through their course intra-operatively, in-hospital and post-discharge and to identify the areas of the present clinical pathway that could be modified to accommodate an outpatient OKA program. Methods This study was conducted as a case review by chart audit retrieving data from OKA patient s medical charts that underwent surgery at BRHC from January, to February, 6. The patient list was retrieved with permission from Medical Records at the BRHC of the Prairie Mountain Health Authority. The comprehensive 3

4 list included all of the patients who received an Oxford knee replacement during the specified period. The total number of charts reviewed was 3, with 6 being from (n=6) and 7 from 6 (n6=7). A fillable template form was created that when completed would include the desired information to be retrieved from the patient s charts (Appendix ). The core areas of information of interest included basic patient demographics, patient characteristics, details of the procedure, hospitalization length, hospital course, details of discharge and readmission/emergency room visits. All subject lines of the form were not always filled as some of the information was either not retrievable from the medical chart or did not apply to the patient. The information retrieved was used to show trends and identify areas of concern regarding the current OKA clinical pathway. Data were compiled from the completed forms of each patient and separated based on the year the patient had the operation. Each general area of interest was separated into the specific information desired (eg. Discharge medication was a specific of details of discharge ). Results Of the patients, 3 (3%) were male ( from, from 6) and 3 (7%) were female ( from and from 6). The patient s home location was recorded as either rural or urban (urban was considered as a home location of either Dauphin, Portage La Prairie, Winnipeg or Brandon, Manitoba). Of the 3 patients, 38 (7%) were rural (33 from and from 6) and (8%) were urban (3 from and from 6). Before the surgery, patients were recommended to attend Pre-habilitation Clinic of which did in and all 7 did in 6. Patients who had previous knee replacement surgery were of interest as well as the type of operation completed. Only 6 patients from had previous replacements including OKAs and TKAs. Only patient from 6 had a previous OKA. Table. Age distribution of patients in chart audit. Mean Age (yrs) 68 (67.69) Max. Age (yrs) Min. Age (yrs) Range (yrs) < >8

5 No assistance w/ assistance No assistance w/ assistance No assistance w/ assistance No assistance w/ assistance STUDY FOR OUTPATIENT OXFORD KNEE AT BRHC Patient's Living Situation # of patients House Apt. House Apt. Spouse/Family Alone Fig. Graph showing the different living situations of the patients. Assistance was considered as being any regular visits from Home Care or regular assistance from family members who lived outside the household. Table. Medical status of the patients prior to surgery. ASA Classification* Body Mass Index (BMI) (kg/m ) 3 Mean Max. Min. Range *The American Society of Anaesthesiologists (ASA) Physical Classification is a number determined by the anaesthesiologist to describe the patient s physical state or the degree to which they are ill. There weren t any patients who were categorized higher than an ASA Number of 3. The classifications are as follows 3 : ASA normal healthy patient ASA patients with mild systemic disease ASA 3 Patients with severe systemic disease ASA patients with severe systemic disease that is a constant threat to life ASA Moribund patients who are not expected to survive without the operation ASA 6 a declared brain-dead patient whose organs are being harvested for donor purposes

6 Medical Conditions of patients # of patients with conditions Fig. Reported chronic medical conditions of the participating patients. Vascular and metabolic conditions were reported in 6% and % of patients, respectively. Examples of how conditions were categorized are as follows: Cardiac eg. Myocardial infarction, atrial fibrillation Respiratory eg. COPD, asthma Vascular eg. Hypertension, history of deep vein thrombosis, cerebrovascular accident Metabolic eg. Diabetes mellitus, hypothyroid, dyslipidemia Gastrointestinal eg. Gastroesophageal reflux disease, diverticulitis Urinary/Nephrology eg. Benign prostatic hypertrophy, urinary stress incontinence Neurological eg. neuralgias, neuropathies Blood/Cancer eg. Hemophilia, leukemia, lymphoma OSA obstructive sleep apnea Table 3. Number of patients who gave pre-operative concern and the reason for concern. Total Thrombocytopenia NSAID Allergy Metal Allergy Cardiac Concern 3 Airway Concern History of DVT/PE* - BMI/Leg Size Atrial Fibrillation Anaesthetic Concern Increased CK (Malignant Hyperthermia concern) - *Deep vein thrombosis (DVT)/Pulmonary Embolism (PE). Some patients gave more than one concern. 6 Total Multiple Allergies - 6

7 Most participants received a spinal anaesthetic, a total of 8 (9%) patients ( from and all 7 from 6), but 3 (6%) received a general anaesthetic, (%) received a spinal and epidural and (%) received a spinal and a general anaesthetic. Table. Intra-operative complications and duration of time the tourniquet was inflated during surgery. Complications Tourniquet Time (min) Total Atrial Thrombocytopenia Reverse Mean Max. Min. Range Fibrillation Tourniquet Effect There weren t any complications during the operations for the patients in 6. The reverse tourniquet effect happens when the patient bleeds more profusely during the operation when the tourniquet is inflated than when it is deflated. Of all the OKAs performed in, there were complications in 8% of them. Length of Stay # of patients Length of Stay (days) Fig. 3 Graph for length of stay in-hospital of patients in study. All patients were required to stay at least day in hospital post-operatively as part of the current clinical pathway. There weren t any patients who stayed more than 3 days in either or 6. 7

8 # of patients who experienced complications 3 3 In-hospital Complications Fig. Graph displaying the complications experienced by patients post-operatively while admitted to hospital. Each patient was given a score for each different type of complication. The scale is as follows: Complications Scale = didn t experience complication at all = minor amount experienced, slight concern = causing patient distress, more concerning 3 = debilitating to patient, very concerning Although a score of describes that the patient did not experience the complication at all, this may not be true as the information could only be retrieved if the patient expressed concern to a health care professional and if it was documented in the patient s medical chart. Nausea and bleeding were the only complications that had a patient score a 3. The total numbers of non-zero scores for each complication are: Nausea Bleeding Infection 3 Medical Pain Nausea Bleeding Infection Medical Pain 6 8

9 Table. Medical concerns documented while in-hospital. 6 Infection 3 Edema 3 Urinary retention Urinary retention Allergy Slight edema Hyperglycemia Bleeding Edema - DVT Hematoma Atrial Fibrillation Constipation Itching Desaturations - Thrombocytopenia - Table 6. Consultations requested to treat patients admitted following OKA. 6 Total Attending* Cardiology Anaesthesia Urology Orthopaedics Imaging Total Attending* Spinal 8 6 * Attending refers to a call going out to the admitting physician or physician s assistant from the nursing staff outside of regular rounds. Some patients required calls to multiple different disciplines. Post-operative medications administered # of patients administered medication Fig. Graph showing which patients were given specific medications listed as standing orders in the current clinical pathway. Heparin u was given for preventative DVT prophylaxis as one dose before the beginning of the surgery and one later in POD#. Most medications administered were used for pain control and 9

10 Independent Assisted Independent Assisted Independent Assisted STUDY FOR OUTPATIENT OXFORD KNEE AT BRHC to treat nausea. The most frequently used drugs were Tramacet, Ketorolac and Hydromorphone for pain control and Dimenhydrinate for nausea. Pain control was also achieved by cryotherapy using a cooling cuff that was applied to the patient s operative knee. Of the group, (96%) of patients had the cooling cuff applied to their knee and of the 6 group, all 7 (%) of patients received the cooling cuff as treatment for pain. In regards to DVT prevention prophylaxis, a Thromboembolic Disease Stocking (TEDS) was applied to the patient s non-operative leg to help prevent the formation of blood clots postoperatively. Of the 3 patients, (98%) had a TEDS applied ( from and 7 from 6), although the data was unavailable for one patient. One patient in also received a Sequential Compression Device (SCD), which actively inflated and deflated to help circulate blood and prevent clotting as the patient was elderly and had a history of a DVT and subsequent PE. # of patients 3 3 Mobility w/ crutches or walker POD# POD# POD# Fig. 6 Graph showing the mobility of the patient as graded by Physiotherapy or Occupational Therapy for each day of the patient s stay in-hospital. Patients were seen by PT and OT on POD# and requested the patient mobilize if they were agreeable to movement. None of the patients were able to mobilize independently with crutches or a walker on the same-day as surgery (POD#). Patients who were in hospital for days or more and were independently mobilizing POD# were recorded as independent on POD# as well. One patient in both and 6 were not able to mobilize at all POD# due to post-operative complications. None of the patients were discharged before they were able to mobilize independently, other than a single patient who was discharged to another hospital.

11 As part of the clinical pathway, outpatient physiotherapy is to be arranged before patients are discharged from the hospital. The outpatient physiotherapy could be located at the hospital, another location in Brandon or in the patient s hometown. Outpatient physiotherapy was arranged for (96%) of patients and all 7 (%) of the 6 patients. Data was unavailable for patients in. Occupational Therapy requested Home Care for 3 (7%) patients in and patients in 6. Patients were often discharged home with (98%) being sent with family and (%) patient from was discharged to another hospital in their hometown. Follow-up Time 3 # of patients day days 6 days week weeks 3 weeks 6 weeks Fig. 7 Follow-up times requested by surgeon given with discharge instructions. Many patients were given two follow-up dates for staple removal and then routine surgical follow-up.

12 Discharge Medications # of patients who received prescriptions for medications Fig. 8 Prescription medications sent with the patient upon discharge. Discharge medications were not available for patients in. Table 7. Emergency room visits by patients post-discharge. 6 Elapsed time since discharge Reason for Emergency room visit day 8 days days 3 months months 9 months year months Postoperative Swelling DVT (negative by US) No diagnosis No diagnosis No diagnosis No diagnosis TKA revision of Oxford Knee No diagnosis Related to OKA Yes Yes No No No No Yes No US = ultrasound The emergency room visits at day and 8 days were by the same patient. Two (%) of the patients in visited the emergency room for reasons related to surgery. There was only (%) failure of the OKA that led to a TKA revision -year postoperatively. Discussion Gender Distribution, Age and Obesity Upon examination of the patient demographics for the participants in this study, a few trends are worth discussion. Over half of the patients in this study were female

13 which suggests that osteoarthritis (OA) of the knee is more common in women than in men. This trend has been noted before in the Framingham Osteoarthritis Study with female sex being termed a risk factor for developing OA in the knee. It is important to note that there was not an evenly dispersed age distribution in this study, but rather most of the patients fell in the age range of 6-7 years (3%). Increasing age is another specific risk factor that has been attributed to developing OA in the knee as the cartilage begins to disappear with overuse and injury to the joint through the lifetime. Despite this, many patients were below and above that range and there was rarely a difference in how quickly patient recovered or how well they tolerated the surgery based solely on age. Of the patients aged 6 years or less, 8 of them were female including the three youngest patients ( at 3 years and at years). This would suggest that the OA in these patients could be attributed more to the fact that these patients were female rather than increasing age. In saying that, it is important to consider obesity as a risk factor. Regarding the three youngest patients, only of them had a BMI below 3 and one of them had the largest BMI of all 3 patients at 9.. This is not surprising as obesity has also been identified as a risk factor for developing OA in the knee joint by the Framingham study. The evidence presented from this study would support that claim as the average BMI for both years is over 3 kg/m (33.7 kg/m for and 3.7 kg/m for 6) which is considered obese, and there were many patients who had a BMI over kg/m which is considered morbidly obese. In regards to how well patients with larger body mass tolerated the surgery, BMI seemed to have little effect on the recovery time although it is hard to distinguish whether a longer recovery time was due to the obesity itself or the comorbidities that many of these patients have along with their obesity. It is also important to consider how obesity can present challenges with inducing anaesthesia and recovery from surgery. Obese patients often have difficult airways due to the excess soft tissue and thus a general anaesthetic may not be able to be administered. As well, due to the massive amount of body fat tissue, a spinal anaesthetic may not be as easy to perform and may spread more due to increased blood volume, increased fatty infiltration and a decreased epidural space due to the increased intra-abdominal pressure 6. Although being female seems to make it more likely that a patient will develop OA, it does not affect how well a patient recovers and thus has no implications for a guideline in an outpatient program. On the contrary, obesity may play a role in how well the patient is able to perform transfers and mobilize based on solely on the burden of weight on the recovering knee and thus may need to be considered when creating an outpatient program for OKAs. Patient s Home Location and Pre-habilitation Clinic The distribution of patient s home location was surprisingly shifted towards rural locales (7%). This has important implications for the consideration of the outpatient OKA program as these patients will need to travel to return home on the same day of surgery, may not be able to access health care if a complication arises depending on the health care availability in their home community and may not be 3

14 able to return to the BRHC immediately if they have traveled a fair distance. Although only one patient in the study returned to emergency day following discharge to investigate swelling, it is important to have a plan in place if a complication did arise for all patients. Because so many patients are of rural descent, an outpatient program may require that patients must stay within a certain distance of the BRHC for day post-operatively to ensure that if any complication arises they can be appropriately attended to. Although this would seem to be similar to the current pathway where patients are admitted for a minimum of one day post-op, this type of implementation would free-up any hospital beds that would be taken up by OKA patients, which would save money and allow for those beds to be available if another patient in worse condition needs to be admitted. Education for patients about how to prepare and manage themselves post-op may be helpful for these patients especially, which is the main purpose of the Prehabilitation Clinic that was attended by all but patient. This rate of attendance was a promising sign for the current clinical pathway and should be continued in an outpatient setting. Medical Status, Pre-op Concern and Surgical Complications In regards to a history of OA, only 3% had a previous knee replacement performed with of 7 having undergone a previous OKA on the opposite knee and only having TKAs. This evidence may speak to the efficacy of the OKA operation as many patients who have had previous Oxford knee replacements are electing to have another over a TKA. This may also be affected by the quicker recovery time associated with an OKA as compared to the TKA and thus an outpatient program would make the experience that much better for the patients. Many of the OA patients were accompanied by several comorbidities, the most prevalent being vascular and metabolic disease. This is not an unexpected phenomenon as hypertension is associated with an increase in age and diabetes with obesity, two factors that have been attributed to the development of OA 6,7. The ASA Classification is a quick way to categorize the overall health of the patient based on their chronic medical conditions and is perhaps a useful way to summarize and properly select which patients would be candidates for an outpatient OKA. The vast majority of patients were an ASA score of (66%) and still tolerated the surgery and recovery well. Despite this, only of the 3 patients that had an ASA score of 3 spent more than day in the hospital post-op and thus the ASA Classification may not be a useful predictive tool for patient selection for outpatient OKAs. Pertaining to pre-operative concern, allergies of different sorts were the most common issue. Despite this, only intra-operative complications arose in 3 of the patients who presented with pre-operative concern. The current patient screening processes should be considered efficacious with only 6% of patients experiencing an intraoperative complication, none of which can be attributed to any of the surgical staff. This should speak to the effectiveness of the current OKA program at the BRHC, which would suggest that setting would be able to manage an outpatient program well.

15 Tourniquet Time and Anaesthesia The use of a tourniquet in knee surgery is extremely common, but may be harmful to the rehabilitation of the patient 8. It has been described that the use of a tourniquet in TKAs can lead to poor knee flexion post-op and quadriceps weakness up to 3 months post-op, as well as many other problems 8. The tourniquet is advantageous in the sense that it helps to minimize blood loss during surgery, which is beneficial to the patient and the view of the surgical field 8. In this study, a tourniquet was used with every patient (though it was deflated during one operation due to a reverse tourniquet effect) with mean times of and minutes for and 6 respectively, and the range of times for was quite large at 3 minutes. Because of the disadvantages the use of a tourniquet is for rehabilitation, the use of it may be called into question for an outpatient OKA program. Despite this, blood loss is a large problem intra-operatively and thus it may be worth investigating what is an ideal tourniquet inflation time to minimize both blood loss and harm to the leg. The use of the tourniquet also affects fibrinolytic activity at the surgical site, which can lead to more post-operative bleeding 9. It may be worth considering the use of tranexamic acid, an antifibrinolytic drug that when used perioperatively has shown to reduce blood loss significantly during orthopaedic surgery, to allow for a shorter tourniquet time without compromising hemostasis of the patient. The use of local anaesthetic was well tolerated by the patients and should be continued in an outpatient program. Most patients received a spinal anaesthetic for the surgery (9%), but this may have implications in the patient s recovery. When used in an outpatient setting, spinal anaesthetic can lead to problems with urinary retention, a complication that was experienced the most by the patients in this study. This would be a problem for an outpatient program where a larger proportion of the patients come from a rural setting and may not have access to the immediate medical care needed to treat urinary retention. A different approach to anaesthesia may need to be taken for outpatient OKAs, perhaps leaning towards general anaesthesia (which seemed to have little or no impact on patient s recovery time in this study) or an adductor canal block which is also a suggested type of anaesthesia put forward by the Zimmer Biomet Instructional course. Length of Stay and Hospital Course A strong indicator that an outpatient OKA program could be successful at the BRHC is that most patients were only admitted for day post-op (68%) and that none of the patients spent more than 3 days in-hospital. With most patients staying overnight with only minor complications, an outpatient program may be more likely to succeed. The most common complications that were experienced by patients during their hospital course were excessive bleeding from surgical site, pain and nausea. In regards to bleeding, none of the drugs that are included as a standing order in the current clinical pathway help to stop bleeding. On the contrary, most

16 patients were given doses of Heparin u (8%) to help prevent the formation of a DVT, which increases bleeding. As well, it is worth noting that many patients used a Continuous Passive Motion (CPM) device while lying in their hospital bed, which often increased bleeding and did not seem to affect the flexibility or recovery time of the patient. The most common consultation that was requested was a call to the attending physician or physician s assistant, which was most often observed to be because of excessive bleeding. A query into whether administering tranexamic acid, using a different style of wound closure or eliminating the use of CPM would help reduce post-op bleeding would be beneficial when considering outpatient OKAs. Nausea was another complication that was often not controlled well. In patients who experienced nausea, there was often emesis and their mobility was compromised which affected their rehabilitation and physiotherapy assessment. A frequently used drug, Dimenhydrinate, was often given to help control the nausea post-op, and Ondansetron and Metoclopramide were occasionally used post-op, but more frequently intra-operatively, to control it as well. Although this may suggest that a different type of anaesthetic should be used, research suggests that nausea is experienced more often with general anaesthesia than with a regional and therefor a spinal or adductor canal block may be the best option to prevent nausea post-op. Nausea post-op may be more strongly correlated with length of surgery rather than the type of anaesthetic, which may not be a controllable factor in all cases. In regards to pain, the data suggests that it was a large problem for many patients. Although this was true in some cases, many of the patients tended to tolerate the pain well and when analgesic medication was administered their pain often went from 6-7/ to a -3/ on a pain scale. Many of the post-op medications administered were used to control pain including some of the most frequently used such as Tramacet, Hydromorphone and Ketorolac. As well, the use of a cooling cuff was often effective in pain control for patients as was tolerated well by 96% of patients. Most of the medical concerns with the patients while in-hospital were related to either the anaesthetic, allergies or pre-existing medical conditions. Urinary retention was the most common issue, but 6% of the patients who experienced it were males with pre-existing urologic problems such as benign prostatic hypertrophy. Examination proved that a clot was non-existent in both patients presenting concern of a DVT due to edema in the leg. TEDS were used in all patients (other than one of which information was not available) and seem to be effective in helping to reduce post-op swelling and clot formation. Infection concern was the least prevalent complication as only minor swelling, redness and fever were often noted. Only 3 (6%) patients were administered Ancef or Keflex to treat a possible infection, none of which returned to emergency later. Mobility and Living Situation The most significant result in regards to the mobility of the OKA patients is that none of the participating patients were able to mobilize without assistance POD#. Despite this, 9% of patients were able to perform all transfers and mobilize independently POD# with either crutches or a walker. If an outpatient OKA 6

17 program is to be implemented, any eligible patient will need to have assistance from a capable individual POD#. A capable individual would be someone who could manage the patient s weight if they were to be unsteady, dizzy or unable to move in the first few days they were home and can help the patient with maintaining dressings, managing equipment or in an emergency situation. This would perhaps be difficult for patients who are having trouble with nausea, have debilitating medical conditions or who are obese and have a large body weight. The importance of the living situation for each patient would become more significant in an outpatient setting. Many of the patients in this study (8%) lived with a spouse or family member in a house or apartment who was supportive and able to assist the patient during recovery. For an outpatient OKA program, having a supportive individual with the patient at all times in those first few days post-op will be essential for the success of such a program. This may mean that patients who live alone may need to have Home Care set-up upon arrival or have another capable individual stay with them until they are able to manage on their own again. In this study, patients had assistance from outside family or Home Care on a regular basis before the operation and Home Care was arranged for 3 patients post-op. Whether the patient lives in a house or apartment is less important than the amount of stairs that are required to enter and move about the home. It is important that patients mobilize as soon as possible following surgery as it is good for the rehabilitation of the knee and speeds up recovery. This is also a reason for the necessity of having a capable person stay with the patient for the first few days immediately post-op. Discharge and Emergency Visits Outpatient physiotherapy was arranged at the patient s preferred location for all (other than the patients who s physiotherapy information was not attainable) of the patients in the study. One of the advantages of an OKA over a TKA is a quicker recovery and the continuation of physiotherapy to help rehabilitate the knee once the patient is discharged is essential for the program to be a success. The evidence presented shows that the most common follow-up time was -3 weeks. Different lengths of time for follow-up often occurred in cases where complications arose inhospital such as bleeding or possible infection, or if the patient was to return earlier for staple removal and then later for surgical follow-up. Tramacet and Ketorolac were the most common prescription medications used to control pain postdischarge and Acetylsalicylic acid (ASA or Aspirin) was often used for DVT prevention prophylaxis. Other medications were given when an allergy was present, infection was suspected, a drug had caused an adverse reaction previously or in special cases due to chronic medical conditions. Of all 3 patients, only (6%) patients visited the emergency room for a reason pertaining to their OKA. Of these patients, only patient returned within the same week and a diagnosis of a DVT was dismissed by ultrasound. The other patient returned year following the surgery due to failure of her Oxford knee and required a TKA revision of it. This evidence clearly supports the quality of the current OKA program when only % of patients visited the emergency room for immediate post-surgical complications and only % 7

18 of the operations failed within time frame of the study. These data suggest that the current program is successful and an upgrade to an outpatient program is possible. Conclusion This case review study was performed to examine the feasibility for the establishment of an outpatient Oxford Knee Arthroplasty program at the Brandon Regional Health Centre. The evidence provided through a medical chart audit (n=3) from January to February 6 of all the OKA patients at BRHC suggests that the clinical pathway already established has been successful to this point. Examination of the main complications and hindrances to an outpatient program for this surgery has suggested that only minor changes may need to occur to the already existing clinical pathway, with a focus on proper patient selection and interdisciplinary care. Recommendations for patient selection based on the matters discussed that would allow for an outpatient program in coordination with Zimmer Biomet s Instructional Course are as follows : ) A restriction may need to be put on BMI or body weight (eg. Maximum BMI of 3) as these patients may have a more difficult time with mobility unless there are several people able to stay with them to assist with transfers and walking. Patients with larger BMIs may need to spend a day in-hospital to make sure they have the assistance they need for mobility, and also because it may take longer for the anaesthetic to be cleared out of their system due to the volume of distribution of the drugs given. The ASA Classification may not be a reliable score to use to determine if a patient would be a good candidate for an outpatient procedure and certain chronic medical conditions (eg. History of cardiac disease) may need to be considered as a contraindication to outpatient OKA surgery. ) Pre-habilitation clinic should be a mandatory part of the clinical pathway as the education the patient gains is incredibly valuable for the success of their recovery, especially in an outpatient setting. 3) It is essential that each patient have a capable spouse, family member, friend or health care professional available to them hours a day for the first few days of recovery to assist with mobility and activities of daily living (ADLs). This is important not only for the rehabilitation of the patient s knee, but also for safety concerns if a complication happened to occur post-discharge. The ability of the assisting person to manage the patient s weight may vary with the amount of stairs in the household as well because stairs may make it more difficult for the patient to maintain their ADLs. In an ideal situation, the assisting person will be able to help the patient climb stairs, as they are a necessary part of the patient s rehabilitation. ) It may be required that patients remain within a certain distance of the BRHC (eg. hour) for the first day post-op such that they are close enough to the emergency room if some complication were to occur. This restriction may also depend on the home location of the patient, whether it is rural or another urban center, and if they will be able to access time-sensitive 8

19 emergency care if needed. This may necessitate the use of hospital housing for patients to stay overnight in the city at an affordable price, but still allow for the hospital bed they would have been in to be free. ) The type of anaesthetic may need to be changed to general anaesthetic or a regional adductor canal block. The general anaesthetic would allow the patient a quicker recovery time post-op, but may increase the incidence of nausea, which is a complication that is already frequent with the present use of a spinal anaesthetic. The adductor canal block may be a better option though it may be a difficult procedure to perform in order to produce satisfactory anaesthesia. The choice of drugs to produce anaesthesia may be worth examination in order to find the drugs with proper profiles for this type of program. 6) Local anaesthetic should continue to be instilled into the wound intraoperatively as it is effective and has no apparent significant disadvantages. 7) The use of tranexamic acid and a reduction in the amount of time that the tourniquet is inflated may be a useful consideration. Tranexamic acid would help to prevent intra-operative blood loss and allow for a shorter tourniquet inflation duration, allow for the tourniquet to be inflated to a lower level and will help reduce the damage to the leg. The use of a glue mesh in wound closure may be another consideration to help reduce the amount of post-op bleeding, which is currently the largest complication experienced by patients. The use of CPM should also be discontinued to help reduce the amount of post-op bleeding, as there seems to be little benefit for its use with significant harm caused. 8) Patients may need to be given more Ondansetron or Metoclopramide intraoperatively to help reduce the amount of nausea experienced in recovery. 9) Patients should meet certain expectations before they are allowed to leave the hospital. This could include sitting up independently, regaining feeling in all of their body and urinating sufficiently. This may require the hospital to have up to 3-hour stay capabilities to accommodate the patient. ) Patients should continue to receive a cooling cuff, TEDS, and see physiotherapy/occupational therapy the same day as the surgery and have outpatient follow-up arranged. Patients should be educated in how to use a cooling cuff and TEDS at home and it should be recommended that they have them at home for their recovery. It should also be confirmed that a patient has either a walker or crutches at home for recovery. For patients with a high risk for DVT, an SCD should be received for better anti-coagulation prophylaxis. The conversion of the current clinical pathway for OKAs to an outpatient OKA program would not only benefit the patient, but would also be beneficial for the hospital. Space on the surgical ward would become more flexible with a large proportion of OKA patients sent home on the same day as the surgery. Although the data is not presented in this study, it would be worth exploring into the amount of money that could be saved if these patients did not have to stay in a hospital bed overnight following every OKA. Even a slight reduction in the amount of overnight stays with the alternative option for outpatient OKAs would 9

20 be a cost-saving program for the hospital. An outpatient Oxford Knee Arthroplasty program at the Brandon Regional Health Centre would be an appealing option for patients, a cost-saving and beneficial endeavour for the hospital, and with proper attention to detail and patient selection, it could be an innovative and successful program for orthopaedic medicine in Manitoba. References. Goodfellow, John, O Connor, John, Dodd, Christopher, Murray D. Unicompartmental Arthroplasty with the Oxford Knee. th ed. Woodeaton, Oxford: Goodfellow Publishers Ltd.;.. Outpatient Alternative Oxford Partial Knee Arthroplasty: Advanced Instructional Course. In: Zimmer Biomet Institution. 3. Anaesthesia Physical Classification System. Cleveland Clinic. hysical_classification_system. Published. Accessed August, 6.. Felson DT. The epidemiology of knee osteoarthritis: Results from the framingham osteoarthritis study. Semin Arthritis Rheum. 99;(3 SUPPL. ):-. doi:.6/9-7(9)96-i.. Garrouste-Orgeas M, Troché G, Azoulay E, et al. Body mass index: An additional prognostic factor in ICU patients. Intensive Care Med. ;3(3):37-3. doi:.7/s Adams JP, Murphy PG. Obesity in anaesthesia and intensive care. Br J Anaesth. ;8():9-8. doi:.93/bja/ Benetos A, Waeber B, Izzo J, et al. Influence of age, risk factors, and cardiovascular and renal disease on arterial stiffness: clinical applications. Am J Hypertens. ;():-8. doi:s [pii]. 8. Dennis DA, Kittelson AJ, Yang CC, Miner TM, Kim RH, Stevens-Lapsley JE. Does Tourniquet Use in TKA Affect Recovery of Lower Extremity Strength and Function? A Randomized Trial. Clin Orthop Relat Res. 6;7(): doi:.7/s Dunn CJ. Tranexamic acid a review of its use in surger and other indications. Goa, KL. 999;7(6):-3.. Song D, Greilich NB, White PF, Watcha MF, Tongier WK. Recovery profiles and costs of anesthesia for outpatient unilateral inguinal herniorrhaphy. Anesth Analg. ;9(): doi:.97/ Koivuranta M, Laara E, Snare L, Alahuhta S. A survey of postoperative nausea and vomiting. Anaesthesia. 997;():3-9. doi:./j az3.x.