Experts , however , have commented that there may be under-utilization of OAT due to patient factors , physician factors , or regional practice variations and that sub-optimal patient management may also occur .
These models are not suitable for all patients and require the identification and education of suitable c and i date s. Potential advantages of POC devices include improved convenience to patients , better treatment compliance and satisfaction , more frequent monitoring and fewer thromboembolic and hemorrhagic complications .
Potential disadvantages of the device include the tendency to underestimate high INR values and overestimate low INR values , low thromboplastin sensitivity , inability to calculate a mean normal PT , and errors in INR determination in patients with antiphospholipid antibodies with certain instruments .
Although treatment satisfaction and quality of life ( QoL ) may improve with POC INR monitoring , some patients may experience increased anxiety or preoccupation with their disease with these strategies .
The majority of studies reported favourable impacts of POC INR monitoring on QoL and found better treatment satisfaction with POC monitoring .
UNLABELLED SUBJECT OF THE EVIDENCE -BASED ANALYSIS : The purpose of this evidence based analysis report is to examine the safety and effectiveness of point-of-care ( POC ) international normalized ratio ( INR ) monitoring devices for patients on long-term oral anticoagulation therapy ( OAT ) .
CLINICAL NEED TARGET POPULATION AND CONDITION Long-term OAT is typically required by patients with mechanical heart valves , chronic atrial fibrillation , venous thromboembolism , myocardial infa rct ion , stroke , and /or peripheral arterial occlusion .
It is estimated that approximately 1 % of the population receives anticoagulation treatment and , by applying this value to Ontario , there are an estimated 132,000 patients on OAT in the province , a figure that is expected to increase with the aging population .
Patients on OAT  are regularly monitored and their medications adjusted to ensure that their INR scores remain in the therapeutic range .
This can be challenging due to the narrow therapeutic window of warfarin and variation in individual responses .
Optimal INR scores depend on the underlying indication for treatment and patient level characteristics , but for most patients the therapeutic range is an INR score of between 2.0 and 3.0 .
There is currently no population -based Ontario data to permit the assessment of patient care , but recent systematic review s have estimated that less that 50 % of patients receive OAT on a routine basis and that patients are in the therapeutic range only 64 % of the time .
OVERVIEW OF POC INR DEVICES POC INR devices offer an alternative to laboratory-based testing and venipuncture , enabling INR determination from a fingerstick sample of whole blood .
Independent evaluations have shown POC devices to have an acceptable level of precision .
They permit INR results to be determined immediately , allowing for more rapid medication adjustments .
POC devices can be used in a variety of setting s including physician offices , ACCs , long-term care facilities , pharmacies , or by the patients themselves through self-testing ( PST ) or self-management ( PSM ) techniques .
With PST , patients measure their INR values and then contact their physician for instructions on dose adjustment , whereas with PSM , patients adjust the medication themselves based on pre-set algorithms .
EffectivenessDoes POC INR monitoring improve clinical outcomes in various setting s compared to st and ard laboratory-based testing?Does POC INR monitoring impact patient satisfaction , QoL , compliance , acceptability , convenience compared to st and ard laboratory-based INR determination ?
Cost-effectivenessWhat is the cost-effectiveness of POC INR monitoring devices in various setting s compared to st and ard laboratory-based INR determination ?
ANTICOAGULATION CONTROL Anticoagulation control is measured by the percentage of time INR is within the therapeutic range or by the percentage of INR values in the therapeutic range .
Comparing Self-Management of Oral Anticoagulant Therapy with Clinic Management
Context Although many out patients require oral anticoagulation , the optimal management of outpatient anticoagulation remains uncertain . Studies have demonstrated the feasibility of patient self-management using portable coagulometers , but the studies that compared patient outcomes with self-management and those with conventional management in an anticoagulation clinic did not find a better outcome with self-management . Contribution In this r and omized , controlled trial of 737 patients , patients assigned to self-management of anticoagulation achieved a similar level of control and had fewer adverse events than patients assigned to conventional management . Implication s Health care providers should begin to implement patient self-management of oral anticoagulation with portable coagulometers in mainstream practice . The Editors Indications for oral anticoagulant treatment to prevent thromboembolic disease have increased in recent years ( 1 ) . Prothrombin times must be monitored frequently in patients taking oral anticoagulants to determine the safest dose and to minimize the risk for complications . The clinical management of oral anticoagulant treatment improved greatly after the international normalized ratio ( INR ) was introduced as a measurement of anticoagulation intensity ( 1 ) . The establishment of accurate therapeutic INR ranges was also beneficial . Target ranges include the safest INR values that carry the lowest risk for hemorrhagic or thromboembolic complications ( 2 ) . Despite these improvements , however , serious complications are still associated with oral anticoagulant treatment ( 3 , 4 ) , and management by specialized staff at anticoagulation clinics seems to be safer than other clinical strategies in terms of numbers of complications ( 5 - 7 ) . Currently , portable coagulometers are available for determining INR easily and reliably ( 8) . This technology provides interesting clinical models for the control of oral anticoagulant treatment , the most promising of which are patient self-testing and patient self-management . For patient self-testing , patients measure INRs themselves and ask their referring physicians for the proper anticoagulant dose . Patient self-management assumes that patients will adjust their own doses and is the most autonomous strategy . Several published studies have compared these strategies with usual care ( that is , monitoring of oral anticoagulant treatment by practitioners ) ( 9 - 13 ) or with specialized anticoagulation clinics ( 14 - 18 ) . Although these studies showed that both patient self-testing and patient self-management are feasible , their sample s were relatively small ( 9 , 11 , 13 , 14 - 18 ) or included selected patients with mechanical valve prostheses ( 10 ) or patients older than 65 years of age ( 12 ) . In general , previous studies indicate that patient self-management may be superior to management by general practitioners or anticoagulation clinics in quality of INR control ( 10 - 18 ) . In addition , Krtke and Krfer ( 10 ) , Beyth and associates ( 12 ) , and Sawicki ( 13 ) reported a decrease in major complications among self-managed patients compared with patients managed by general practitioners . To date , no published data have suggested a better clinical outcome ( decrease in associated complications ) with patient self-management than with specialized management at an anticoagulation clinic ( 5 , 19 ) . We performed a r and omized , controlled trial to directly compare self-management of oral anticoagulant treatment , as evaluated in terms of efficacy and safety in unselected patients , with management in an anticoagulation clinic . Methods Study Design The Alternative Control of Oral Anticoagulant Treatment ( ACOA ) trial is a single-center , central ly r and omized , controlled study that was performed at Hospital de la Santa Creu i Sant Pau , Barcelona , Spain , from January 2001 to July 2002 . The hematologists who manage our anticoagulation clinic use a homogeneous dosing protocol and st and ard protocol s to manage situations that increase clinical risk . The clinical staff includes trained nurses . Computers control the clinical data and INR records , ensuring excellent follow-up . Patients and their relatives receive basic education at the beginning of oral anticoagulant treatment , including information on the main characteristics of oral anticoagulants , potential risks , rationale for periodic monitoring , and drug interactions . Samsa and Matchar ( 20 ) recommended that these characteristics be used to provide an appropriate control group in a trial on patient self-management . The institutional review board of our hospital approved the study . Recruitment Phase The recruitment phase began with computerized r and om selection of 1500 patients from the more than 5000 who were receiving oral anticoagulant treatment controlled in our hospital . We included any ambulatory patient 18 years of age or older who had been receiving long-term anticoagulant therapy for at least 3 months before entering the study . We excluded patients who were younger than 18 years of age , who had a severe physical or mental illness without a responsible caregiver , or who were of foreign origin and were unable to underst and Spanish . Once the patient ( or his or her caregiver ) agreed to participate , written informed consent was obtained . Next , central ized telephone r and omization assigned the patient to the experimental group ( patient self-management ) or to the control group ( conventional management ) . The allocation sequence was generated at the hospital 's epidemiology department , and the sequence of r and omization was concealed until the patient was assigned to a group . To facilitate comparability between study groups , this r and omization was stratified according to sex , age ( 70 years of age or < 70 years of age ) , and indication for oral anticoagulant treatment ( 4 groups ) . Members of our anticoagulation clinic enrolled participants and assigned them to groups . Baseline data included demographic details , clinical information on associated risk factors , other medications , previous length of anticoagulant therapy , bleeding or thromboembolic complications during oral anticoagulant treatment , and target INR range . Follow-up for patients assigned to the conventional management group was done immediately . Patients in the self-management group received a training course first , and follow-up was not performed until the nurse teaching the course judged that the patients had acquired a minimum of expertise in self-management . Training Course An educational program was design ed to optimize the number of patients able to underst and and safely perform  self-management  ( Appendix ) . It was similar to the German program developed by Sawicki ( 13 ) but was demographically adapted to the characteristics of the Spanish population , considering differences in daily schedules , diet , educational level , and other idiosyncratic factors . The program consisted of 2 sessions of 2 hours each on consecutive days . A specially trained nurse was responsible for teaching the patients in small , organized groups . The lessons included basic theoretical and practical concepts involving the use of a coagulometer , interpretation of INR , and adjustment of dose . The concepts of target range and dose modification were emphasized when necessary . A simple card system was design ed to help the patient select the correct dose . For each target range , a specific card was provided . Patients were taught to use the portable coagulometer CoaguChek S ( Roche Diagnostics , Mannheim , Germany ) with the appropriate reagent strips . Follow-up Phase Normally , the patients in the conventional management group visited our hospital every 4 weeks to check their INRs . When the INR result was out of target range , our dosing protocol indicated that we should advance the next appointment for INR testing to 1 or 2 weeks . International normalized ratio was determined by means of a st and ard KC 10 coagulometer ( Amelung , Lemgo , Germany ) . As a thromboplastin , we used Thromborel S ( Behring , Marburg , Germany ) . A hematologist experienced in oral anticoagulation management adjusted the dose and made the appointment for the next INR test . Patients in the self-management group performed the INR tests at home once per week using the CoaguChek S kit . They determined the appropriate dose of oral anticoagulant and the time of the next INR test . All of the INR results in both groups were entered into a computer ( in the central system of our anticoagulation clinic or in the portable coagulometers ) to facilitate data management . Patients in both groups were interviewed monthly by telephone to record any complications or changes in their health status . For the conventional management group , these interviews were done approximately midway between hospital visits . The questions addressed minor or major bleeding , thromboembolic events , episodic diseases , changes in long-term medications , and hospital stays . Associated complications were diagnosed and evaluated by a third physician who was not involved in the trial and was unaware of patients ' study group . St and ard criteria were used to diagnose any thromboembolic complications . Transient ischemic attack was diagnosed clinical ly by a neurologist , and superficial thrombophlebitis was diagnosed clinical ly by an angiologist . To diagnose stroke , arterial embolism , venous thromboembolism , pulmonary embolism , or valve thrombosis , we used widely accepted methods ( computed tomography or magnetic nuclear resonance imaging , angiography , surgical diagnosis , Doppler ultrasonography , phlebography , lung angiography or ventilation-perfusion lung scanning , cardiac ultrasonography , or fluoroscopy ) . All thromboembolic complications were considered major events . Life-threatening bleeding or bleeding requiring transfusion or hospital admission was considered a major event . Any other bleeding was considered a minor event . Statistical Analysis Study outcomes were evaluated on an intention-to-treat basis and also on an on-treatment basis .
Experts , however , have commented that there may be under-utilization of OAT due to patient factors , physician factors , or regional practice variations and that sub-optimal patient management may also occur .
These models are not suitable for all patients and require the identification and education of suitable c and i date s. Potential advantages of POC devices include improved convenience to patients , better treatment compliance and satisfaction , more frequent monitoring and fewer thromboembolic and hemorrhagic complications .
Potential disadvantages of the device include the tendency to underestimate high INR values and overestimate low INR values , low thromboplastin sensitivity , inability to calculate a mean normal PT , and errors in INR determination in patients with antiphospholipid antibodies with certain instruments .
Although treatment satisfaction and quality of life ( QoL ) may improve with POC INR monitoring , some patients may experience increased anxiety or preoccupation with their disease with these strategies .
The majority of studies reported favourable impacts of POC INR monitoring on QoL and found better treatment satisfaction with POC monitoring .
UNLABELLED SUBJECT OF THE EVIDENCE -BASED ANALYSIS : The purpose of this evidence based analysis report is to examine the safety and effectiveness of point-of-care ( POC ) international normalized ratio ( INR ) monitoring devices for patients on long-term oral anticoagulation therapy ( OAT ) .
CLINICAL NEED TARGET POPULATION AND CONDITION Long-term OAT is typically required by patients with mechanical heart valves , chronic atrial fibrillation , venous thromboembolism , myocardial infa rct ion , stroke , and /or peripheral arterial occlusion .
It is estimated that approximately 1 % of the population receives anticoagulation treatment and , by applying this value to Ontario , there are an estimated 132,000 patients on OAT in the province , a figure that is expected to increase with the aging population .
Patients on OAT  are regularly monitored and their medications adjusted to ensure that their INR scores remain in the therapeutic range .
This can be challenging due to the narrow therapeutic window of warfarin and variation in individual responses .
Optimal INR scores depend on the underlying indication for treatment and patient level characteristics , but for most patients the therapeutic range is an INR score of between 2.0 and 3.0 .
There is currently no population -based Ontario data to permit the assessment of patient care , but recent systematic review s have estimated that less that 50 % of patients receive OAT on a routine basis and that patients are in the therapeutic range only 64 % of the time .
OVERVIEW OF POC INR DEVICES POC INR devices offer an alternative to laboratory-based testing and venipuncture , enabling INR determination from a fingerstick sample of whole blood .
Independent evaluations have shown POC devices to have an acceptable level of precision .
They permit INR results to be determined immediately , allowing for more rapid medication adjustments .
POC devices can be used in a variety of setting s including physician offices , ACCs , long-term care facilities , pharmacies , or by the patients themselves through self-testing ( PST ) or self-management ( PSM ) techniques .
With PST , patients measure their INR values and then contact their physician for instructions on dose adjustment , whereas with PSM , patients adjust the medication themselves based on pre-set algorithms .
EffectivenessDoes POC INR monitoring improve clinical outcomes in various setting s compared to st and ard laboratory-based testing?Does POC INR monitoring impact patient satisfaction , QoL , compliance , acceptability , convenience compared to st and ard laboratory-based INR determination ?
Cost-effectivenessWhat is the cost-effectiveness of POC INR monitoring devices in various setting s compared to st and ard laboratory-based INR determination ?
ANTICOAGULATION CONTROL Anticoagulation control is measured by the percentage of time INR is within the therapeutic range or by the percentage of INR values in the therapeutic range .