Vox Sanguinis (2014) 107, 153–157 © 2014 International Society of Blood Transfusion DOI: 10.1111/vox.12139
ORIGINAL PAPER
Addressing sample identification errors in a multispecialty tertiary care hospital in Bangalore C. Sindhulina & N. J. Joseph Bangalore Baptist Hospital, Bangalore, India
Background and Objectives Errors in sample identification contribute to patient mismanagement and erroneous administration of blood and blood products. This report describes the rate of sample identification errors over 2 years in a multispecialty hospital in India and possible measures to decrease these errors. Materials and Methods Various measures were taken to reduce the risk of identification errors during sample collection, laboratory processing and administration of blood. The bedside blood grouping method by the slide agglutination technique was also introduced along with other measures in December 2011 as a risk mitigation step to prevent an ABO incompatible transfusion, as well as to provide a method of surveillance for possible errors during transfusion. Results The rate of sample identification errors was 48 and 45 per 1 000 000 among the total tests billed in 2011 and 2012, respectively. In the blood bank alone, the sample identification error rate was 096 in 2011 and 046 in 2012 per 1000 bags of blood and blood components issued after the various steps to prevent such errors in the blood bank were introduced. 81% of these errors (26 out of 32) have been reported in the inpatient setting. 156% (5 out of 32) were repeat errors made by the same technicians.
Received: 21 July 2013, revised 31 January 2014, accepted 1 February 2014, published online 6 March 2014
Conclusions Among the various measures used to reduce sample identification errors, bedside blood grouping allows prevention of ABO incompatible transfusions when performed by trained technicians and may also be used as a method of active surveillance for sample identification errors in hospitals. Key words: bedside blood grouping, preanalytical errors, sample collection errors, sample identification errors, wrong blood in tube.
Introduction Patient’s safety is a prime area of concern addressed by various mechanisms in health care including blood banks and laboratories. Compliance with systems of quality management has contributed to reducing analytical error rates. The distribution of errors throughout the laboratory working process shows that most occur in the pre- or postanalytical Correspondence: Chandrasingh Sindhulina, Bangalore Baptist Hospital, Bellary Road, Hebbal, Bangalore 560024, Karnataka, India E-mail: [email protected]
phases. Among the preanalytical errors, the errors that are difficult to correct are sample identification errors (wrong blood in tube), since these are difficult to identify as errors to begin with. It is estimated that 125% of laboratory errors may have an effect on patient’s health [1]. It is said to be a ‘Wrong blood in tube’ (WBIT) incident when a sample tube is labelled with unique identifiers for one patient, but the blood in the tube is collected from another patient [2]. In the blood bank, wrong blood in tube can be identified by the laboratory when the current ABO typing result disagrees with the known blood group of the patient. This does not identify instances in which two patients have
153
154 C. Sindhulina & N. J. Joseph
the same ABO blood type and also does not allow identification of the error if the patient’s blood group is not already known [2]. Sample identification errors also contribute to erroneous administration of blood and blood products. Patient misidentification resulting in incorrectly administered blood units occurs at one of three points: during sample collection (phlebotomy), during laboratory testing or at the time of blood administration. It is estimated that 14–20% of these errors occur before the sample arrives at the laboratory. Although death due to ABO incompatible transfusion is rare (estimated at 1 in 18 million), it represents a greater risk than transfusion acquired infections and also causes significant patient morbidity [2]. Information on such incidents in India is minimal though there are few publications relating to this issue. There are reports from New Delhi which have mainly identified the various types of preanalytical errors and their extent in two hospitals. The majority of errors in these groups were associated with wrong entries in the test request forms [3] and unsuitable samples due to improper collection [4]. It is possible to correct this by supervision and training and by rejection of the unsuitable sample for testing. Using vacutainers for collection also helps in reduction in the number of unsuitable samples received [3]. This report describes the magnitude of sample identification errors encountered in sample collection over 2 years in a multispecialty hospital and identifies the measures that could prevent the same.
Materials and methods This is a descriptive study that analyses the sample collection errors in the laboratory, mainly pertaining to phlebotomy. The Bangalore Baptist Hospital is a 300-bedded multispecialty tertiary care hospital accredited by the National Board for Accreditation for Hospitals and Healthcare Providers (NABH) in Bangalore. The laboratory tests are accredited by the National Accreditation Board for Testing and Calibration Laboratories (NABL). The total billed tests in the laboratory were 306 692 and 368 289 in 2011 and 2012, respectively, in Clinical Chemistry, Immunochemistry, Microbiology, Serology, Haematology, Immunohematology and Clinical Pathology. Approximately 55% of these were from inpatients, and 45% of these were from outpatients. Among these, 24% (16 500 tests) were outsourced to other laboratories. A total of 3108 bags of blood and blood products were issued in 2011 and 4282 in 2012. All outpatient collections and most inpatient collections of blood specimens are done by the
laboratory staff. The urgent samples in casualty and other critical care areas may be collected by the clinical staff as well. Standard operating procedures and in service training are being provided to the staff involved in collection. The blood bags are issued by the blood bank staff at the blood bank counter, and they are collected for transfusion for one patient at a time by the nursing or medical staff from the ward. Vacutainers are used for all blood collections. All the orders and results are electronic on the hospital information system and in the rare instance of a computer system failure. In the outpatient setting, the tubes are labelled by barcodes prior to collection. In the inpatient setting, the blood is collected in tubes labelled manually at the bedside and then barcoded after receipt in the laboratory. Errors in sample identification (wrong blood in tube) that could be due to errors in patient identification and/ or wrong labelling were recorded based on the following: (1) Logging of complaints from clinicians or reports of near miss events and from patients’ feedback, (2) Logging of laboratory detection by manual or automated delta checks and (3) By review of bedside blood grouping which was instituted as an additional measure for every bag of blood which is issued after cross-match by the tube or gel method. The bedside blood grouping is done by a technician using the slide agglutination method at the bedside after issue of every bag of blood before transfusion. The bedside blood group is matched against the group of the issued blood bag as a final check before transfusion in addition to other checks on the bag performed at the bedside. This method of checking was instituted in December 2011. There were no errors in 2011 after this. So, the data for 2011 and 2012 may be considered as pre- and postresults after implementation of this additional step.
Results The rate of sample identification errors among the total billed tests in the laboratory and blood bank including cross-matches was 48 and 45 per 1 000 000 (00048% and 00045%) in 2011 and 2012, respectively (Table 1). The sample identification error rate due to wrong blood in tube in the blood bank alone was 096 in 2011 (3 in 3108 bags) and 046 in 2012 (2 in 4282 bags) per 1000 bags of blood and blood components issued. The activities considered for calculation of errors in the blood bank are cross-matching and issue of bags after screening for blood-borne diseases. Of 81% of these errors (26 out of 32) have been reported in the inpatient setting. 156% (5 out of 32) were repeat errors made by the same technicians. 63% (2 out of 32) of © 2014 International Society of Blood Transfusion Vox Sanguinis (2014) 107, 153–157
Addressing sample identification errors 155
Table 1 Reported sample identification errors in 2011 and 2012
Year
Laboratory test billed
Blood bags issued
Total
Total no of sample identification errors
No of sample identification errors per 1000 000 samples
2011 2012 Total
306 692 368 289 674 981
3108 4282 7390
309 800 372 571 682 371
15 17 32
48 (00048%) 45 (00045%) 46 (00046%)
the errors were made in high-throughput areas such as the labour room. The errors were classified into three types: wrong collection (from the wrong patient, or wrong labelling at collection), wrong label at receipt (wrong labelling during barcoding) and wrong sample used for testing. Of 75% (24 out of 32) of the errors were due to errors during collection. Among these, 58% (14 out of 24) occurred due to wrong identification of the patient (i.e. sample collected from the wrong patient), and 42% (10 out of 24) were due to wrong labelling (i.e. sample collected from the correct patient, but labelled wrongly with another patient’s name and/or number). Twenty-three out of the 32 errors occurred when laboratory technicians were involved in collection, and nine were errors made by non-laboratory personnel (nurses/ doctors). Wrong blood in tube due to wrong labelling was found to be the most common error (8 out of 9) made by non-laboratory personnel. This may be due to the practice of labelling after sample collection, which is followed in most clinical areas, and especially in high-risk clinical areas, such as the Emergency Room and Labour Room. In particular, the cause of the identification errors in the blood bank in 2011 and 2012 is shown in Table 2. All three errors in 2011 were identified because of a mismatch with the historical blood group. In 2012, one error was identified by historical blood group mismatch and another by the bedside blood grouping, even though there was no historical group. It is to be noted that all errors are related to human factors only. No repeat errors by the same technician are noted among the errors related to the blood bank. Various measures instituted to prevent these errors are as below: (1) The name and number were to be checked against the receipt in outpatients and wristband in inpatients. Wristbands have to be present for every inpatient. (2) Induction and continuous training specifically included these topics. (3) Technicians who have made repeat errors in collection were made to undergo repeat training in phlebotomy before certification to do independent collections, © 2014 International Society of Blood Transfusion Vox Sanguinis (2014) 107, 153–157
Table 2 Sample misidentification errors in blood bank
Laboratory error
Wrong blood in tube error – misidentification/ mislabelling during collection of sample Wrong blood in tube error – barcoding error at receipt Total
2011
2012
1 (Wrong sample used for crossmatch even though it was correctly labelled.) 1
0
1
0
3
2
2
and/or they were considered unsuitable for this job and were offered to be placed elsewhere in the organization. (4) Other measures, which were used, include training on standard procedures of sample collection, wristband availability on all inpatients and accountability of the phlebotomist by way of identification on the computer log. (5) Regular review and root cause analysis of the errors. In addition, the following were made mandatory for processing in the blood bank. Patient misidentification resulting in incorrectly administered blood units occurs at one of three points: during sample collection, during laboratory testing or at the time of blood administration. Checks to prevent errors during sample collection: (1) Cross-match samples are not accepted without the identity of the phlebotomist on the accompanying hard copy of the cross-match request. (2) Samples for blood bank tests are received directly at the blood bank and not through a common sample receipt area in the laboratory. This ensured that the cross-match samples were not unnecessarily barcoded (eliminating the scope of error in that step) along with laboratory samples. It also enforced strict
156 C. Sindhulina & N. J. Joseph
non-sharing of samples between laboratory and blood bank. Checks to prevent errors during laboratory testing: (1) Cross-match is done using blood from the segment of the bag, and the unique bag identifier on the segment is recorded at cross-match as well as issue of the particular bag. (2) Bag labels are verified for unit number and unit group by a second technician. (3) All cross-matches (done by the gel/tube method) are followed by a second check of the blood group of recipient sample by the slide agglutination method by a different technician in the blood bank before issue to prevent errors due to use of wrong sample for the cross-match. (4) Only a group of technicians dedicated to blood bank techniques are retained in the blood bank and are trained regularly in these techniques. Checks to prevent errors during administration of blood: (1) During issue of the bag, the segment number of the unit is noted and verified against the segment number in the cross-match slip. (2) A copy of the informed transfusion consent is also submitted to blood bank before issue of blood. (3) The bags for one patient are issued one by one to each ward nurse or attender. Issue of bags for more than one patient at a time is not allowed. (4) A routine bedside check of unit number, cross-match slip, patient’s identity, doctors’ order on the chart and the consent form to verify the identity of the patient for whom the transfusion is intended before transfusing is in place. This is recorded in the chart. (5) Blood grouping of the patients’ blood sample obtained by the finger prick method is done at the bedside by the slide method by a trained laboratory technician to check if it is the same group. The bedside blood group acts as a risk mitigation step, preventing an ABO incompatible transfusion as well as allowing one to identify an existent weakness in the present system which needs to be addressed. Discordant bedside group is recorded as a non-conformity and analysed to identify the weakness in system followed by suitable corrective and preventive action, where feasible. When a discordant bedside blood group is observed, the bag is returned immediately to blood bank; a fresh sample is collected from the recipient for cross-match. The root cause is done as follows: The sample that has been retained in the blood bank which had been used for cross-match is tested for blood group and type. If it is the same as the bedside group, then errors in laboratory testing, issue and administration of the blood bag are looked for. If the blood group is different
from bedside group (and same as unit and documentations), errors related to wrong blood in tube are investigated to identify the point where the error occurred. Quality control for bedside grouping: This is performed only by trained technicians. They have regular training and competence testing. They are also involved in the root cause analysis when a discrepant group is identified. Antisera used for the slide method are carried to the ward by the technician when they are called to perform a bedside blood group. The antisera are otherwise stored in the blood bank and are checked daily for avidity and specificity. Titres are checked as part of quality control during every change in kit lot numbers. The temperature of the storage cooler is also monitored.
Discussion The rate of sample identification errors including those related to transfusion (48 and 45 per 1 000 000) is comparable to reports in studies in the United States in 2006, where an error rate of 55 per 1 000 000 was reported [5]. This also serves as a statement of the present error rates that are being experienced in a hospital like ours. The rate of identification errors reported in the literature varies from
ORIGINAL PAPER
Addressing sample identification errors in a multispecialty tertiary care hospital in Bangalore C. Sindhulina & N. J. Joseph Bangalore Baptist Hospital, Bangalore, India
Background and Objectives Errors in sample identification contribute to patient mismanagement and erroneous administration of blood and blood products. This report describes the rate of sample identification errors over 2 years in a multispecialty hospital in India and possible measures to decrease these errors. Materials and Methods Various measures were taken to reduce the risk of identification errors during sample collection, laboratory processing and administration of blood. The bedside blood grouping method by the slide agglutination technique was also introduced along with other measures in December 2011 as a risk mitigation step to prevent an ABO incompatible transfusion, as well as to provide a method of surveillance for possible errors during transfusion. Results The rate of sample identification errors was 48 and 45 per 1 000 000 among the total tests billed in 2011 and 2012, respectively. In the blood bank alone, the sample identification error rate was 096 in 2011 and 046 in 2012 per 1000 bags of blood and blood components issued after the various steps to prevent such errors in the blood bank were introduced. 81% of these errors (26 out of 32) have been reported in the inpatient setting. 156% (5 out of 32) were repeat errors made by the same technicians.
Received: 21 July 2013, revised 31 January 2014, accepted 1 February 2014, published online 6 March 2014
Conclusions Among the various measures used to reduce sample identification errors, bedside blood grouping allows prevention of ABO incompatible transfusions when performed by trained technicians and may also be used as a method of active surveillance for sample identification errors in hospitals. Key words: bedside blood grouping, preanalytical errors, sample collection errors, sample identification errors, wrong blood in tube.
Introduction Patient’s safety is a prime area of concern addressed by various mechanisms in health care including blood banks and laboratories. Compliance with systems of quality management has contributed to reducing analytical error rates. The distribution of errors throughout the laboratory working process shows that most occur in the pre- or postanalytical Correspondence: Chandrasingh Sindhulina, Bangalore Baptist Hospital, Bellary Road, Hebbal, Bangalore 560024, Karnataka, India E-mail: [email protected]
phases. Among the preanalytical errors, the errors that are difficult to correct are sample identification errors (wrong blood in tube), since these are difficult to identify as errors to begin with. It is estimated that 125% of laboratory errors may have an effect on patient’s health [1]. It is said to be a ‘Wrong blood in tube’ (WBIT) incident when a sample tube is labelled with unique identifiers for one patient, but the blood in the tube is collected from another patient [2]. In the blood bank, wrong blood in tube can be identified by the laboratory when the current ABO typing result disagrees with the known blood group of the patient. This does not identify instances in which two patients have
153
154 C. Sindhulina & N. J. Joseph
the same ABO blood type and also does not allow identification of the error if the patient’s blood group is not already known [2]. Sample identification errors also contribute to erroneous administration of blood and blood products. Patient misidentification resulting in incorrectly administered blood units occurs at one of three points: during sample collection (phlebotomy), during laboratory testing or at the time of blood administration. It is estimated that 14–20% of these errors occur before the sample arrives at the laboratory. Although death due to ABO incompatible transfusion is rare (estimated at 1 in 18 million), it represents a greater risk than transfusion acquired infections and also causes significant patient morbidity [2]. Information on such incidents in India is minimal though there are few publications relating to this issue. There are reports from New Delhi which have mainly identified the various types of preanalytical errors and their extent in two hospitals. The majority of errors in these groups were associated with wrong entries in the test request forms [3] and unsuitable samples due to improper collection [4]. It is possible to correct this by supervision and training and by rejection of the unsuitable sample for testing. Using vacutainers for collection also helps in reduction in the number of unsuitable samples received [3]. This report describes the magnitude of sample identification errors encountered in sample collection over 2 years in a multispecialty hospital and identifies the measures that could prevent the same.
Materials and methods This is a descriptive study that analyses the sample collection errors in the laboratory, mainly pertaining to phlebotomy. The Bangalore Baptist Hospital is a 300-bedded multispecialty tertiary care hospital accredited by the National Board for Accreditation for Hospitals and Healthcare Providers (NABH) in Bangalore. The laboratory tests are accredited by the National Accreditation Board for Testing and Calibration Laboratories (NABL). The total billed tests in the laboratory were 306 692 and 368 289 in 2011 and 2012, respectively, in Clinical Chemistry, Immunochemistry, Microbiology, Serology, Haematology, Immunohematology and Clinical Pathology. Approximately 55% of these were from inpatients, and 45% of these were from outpatients. Among these, 24% (16 500 tests) were outsourced to other laboratories. A total of 3108 bags of blood and blood products were issued in 2011 and 4282 in 2012. All outpatient collections and most inpatient collections of blood specimens are done by the
laboratory staff. The urgent samples in casualty and other critical care areas may be collected by the clinical staff as well. Standard operating procedures and in service training are being provided to the staff involved in collection. The blood bags are issued by the blood bank staff at the blood bank counter, and they are collected for transfusion for one patient at a time by the nursing or medical staff from the ward. Vacutainers are used for all blood collections. All the orders and results are electronic on the hospital information system and in the rare instance of a computer system failure. In the outpatient setting, the tubes are labelled by barcodes prior to collection. In the inpatient setting, the blood is collected in tubes labelled manually at the bedside and then barcoded after receipt in the laboratory. Errors in sample identification (wrong blood in tube) that could be due to errors in patient identification and/ or wrong labelling were recorded based on the following: (1) Logging of complaints from clinicians or reports of near miss events and from patients’ feedback, (2) Logging of laboratory detection by manual or automated delta checks and (3) By review of bedside blood grouping which was instituted as an additional measure for every bag of blood which is issued after cross-match by the tube or gel method. The bedside blood grouping is done by a technician using the slide agglutination method at the bedside after issue of every bag of blood before transfusion. The bedside blood group is matched against the group of the issued blood bag as a final check before transfusion in addition to other checks on the bag performed at the bedside. This method of checking was instituted in December 2011. There were no errors in 2011 after this. So, the data for 2011 and 2012 may be considered as pre- and postresults after implementation of this additional step.
Results The rate of sample identification errors among the total billed tests in the laboratory and blood bank including cross-matches was 48 and 45 per 1 000 000 (00048% and 00045%) in 2011 and 2012, respectively (Table 1). The sample identification error rate due to wrong blood in tube in the blood bank alone was 096 in 2011 (3 in 3108 bags) and 046 in 2012 (2 in 4282 bags) per 1000 bags of blood and blood components issued. The activities considered for calculation of errors in the blood bank are cross-matching and issue of bags after screening for blood-borne diseases. Of 81% of these errors (26 out of 32) have been reported in the inpatient setting. 156% (5 out of 32) were repeat errors made by the same technicians. 63% (2 out of 32) of © 2014 International Society of Blood Transfusion Vox Sanguinis (2014) 107, 153–157
Addressing sample identification errors 155
Table 1 Reported sample identification errors in 2011 and 2012
Year
Laboratory test billed
Blood bags issued
Total
Total no of sample identification errors
No of sample identification errors per 1000 000 samples
2011 2012 Total
306 692 368 289 674 981
3108 4282 7390
309 800 372 571 682 371
15 17 32
48 (00048%) 45 (00045%) 46 (00046%)
the errors were made in high-throughput areas such as the labour room. The errors were classified into three types: wrong collection (from the wrong patient, or wrong labelling at collection), wrong label at receipt (wrong labelling during barcoding) and wrong sample used for testing. Of 75% (24 out of 32) of the errors were due to errors during collection. Among these, 58% (14 out of 24) occurred due to wrong identification of the patient (i.e. sample collected from the wrong patient), and 42% (10 out of 24) were due to wrong labelling (i.e. sample collected from the correct patient, but labelled wrongly with another patient’s name and/or number). Twenty-three out of the 32 errors occurred when laboratory technicians were involved in collection, and nine were errors made by non-laboratory personnel (nurses/ doctors). Wrong blood in tube due to wrong labelling was found to be the most common error (8 out of 9) made by non-laboratory personnel. This may be due to the practice of labelling after sample collection, which is followed in most clinical areas, and especially in high-risk clinical areas, such as the Emergency Room and Labour Room. In particular, the cause of the identification errors in the blood bank in 2011 and 2012 is shown in Table 2. All three errors in 2011 were identified because of a mismatch with the historical blood group. In 2012, one error was identified by historical blood group mismatch and another by the bedside blood grouping, even though there was no historical group. It is to be noted that all errors are related to human factors only. No repeat errors by the same technician are noted among the errors related to the blood bank. Various measures instituted to prevent these errors are as below: (1) The name and number were to be checked against the receipt in outpatients and wristband in inpatients. Wristbands have to be present for every inpatient. (2) Induction and continuous training specifically included these topics. (3) Technicians who have made repeat errors in collection were made to undergo repeat training in phlebotomy before certification to do independent collections, © 2014 International Society of Blood Transfusion Vox Sanguinis (2014) 107, 153–157
Table 2 Sample misidentification errors in blood bank
Laboratory error
Wrong blood in tube error – misidentification/ mislabelling during collection of sample Wrong blood in tube error – barcoding error at receipt Total
2011
2012
1 (Wrong sample used for crossmatch even though it was correctly labelled.) 1
0
1
0
3
2
2
and/or they were considered unsuitable for this job and were offered to be placed elsewhere in the organization. (4) Other measures, which were used, include training on standard procedures of sample collection, wristband availability on all inpatients and accountability of the phlebotomist by way of identification on the computer log. (5) Regular review and root cause analysis of the errors. In addition, the following were made mandatory for processing in the blood bank. Patient misidentification resulting in incorrectly administered blood units occurs at one of three points: during sample collection, during laboratory testing or at the time of blood administration. Checks to prevent errors during sample collection: (1) Cross-match samples are not accepted without the identity of the phlebotomist on the accompanying hard copy of the cross-match request. (2) Samples for blood bank tests are received directly at the blood bank and not through a common sample receipt area in the laboratory. This ensured that the cross-match samples were not unnecessarily barcoded (eliminating the scope of error in that step) along with laboratory samples. It also enforced strict
156 C. Sindhulina & N. J. Joseph
non-sharing of samples between laboratory and blood bank. Checks to prevent errors during laboratory testing: (1) Cross-match is done using blood from the segment of the bag, and the unique bag identifier on the segment is recorded at cross-match as well as issue of the particular bag. (2) Bag labels are verified for unit number and unit group by a second technician. (3) All cross-matches (done by the gel/tube method) are followed by a second check of the blood group of recipient sample by the slide agglutination method by a different technician in the blood bank before issue to prevent errors due to use of wrong sample for the cross-match. (4) Only a group of technicians dedicated to blood bank techniques are retained in the blood bank and are trained regularly in these techniques. Checks to prevent errors during administration of blood: (1) During issue of the bag, the segment number of the unit is noted and verified against the segment number in the cross-match slip. (2) A copy of the informed transfusion consent is also submitted to blood bank before issue of blood. (3) The bags for one patient are issued one by one to each ward nurse or attender. Issue of bags for more than one patient at a time is not allowed. (4) A routine bedside check of unit number, cross-match slip, patient’s identity, doctors’ order on the chart and the consent form to verify the identity of the patient for whom the transfusion is intended before transfusing is in place. This is recorded in the chart. (5) Blood grouping of the patients’ blood sample obtained by the finger prick method is done at the bedside by the slide method by a trained laboratory technician to check if it is the same group. The bedside blood group acts as a risk mitigation step, preventing an ABO incompatible transfusion as well as allowing one to identify an existent weakness in the present system which needs to be addressed. Discordant bedside group is recorded as a non-conformity and analysed to identify the weakness in system followed by suitable corrective and preventive action, where feasible. When a discordant bedside blood group is observed, the bag is returned immediately to blood bank; a fresh sample is collected from the recipient for cross-match. The root cause is done as follows: The sample that has been retained in the blood bank which had been used for cross-match is tested for blood group and type. If it is the same as the bedside group, then errors in laboratory testing, issue and administration of the blood bag are looked for. If the blood group is different
from bedside group (and same as unit and documentations), errors related to wrong blood in tube are investigated to identify the point where the error occurred. Quality control for bedside grouping: This is performed only by trained technicians. They have regular training and competence testing. They are also involved in the root cause analysis when a discrepant group is identified. Antisera used for the slide method are carried to the ward by the technician when they are called to perform a bedside blood group. The antisera are otherwise stored in the blood bank and are checked daily for avidity and specificity. Titres are checked as part of quality control during every change in kit lot numbers. The temperature of the storage cooler is also monitored.
Discussion The rate of sample identification errors including those related to transfusion (48 and 45 per 1 000 000) is comparable to reports in studies in the United States in 2006, where an error rate of 55 per 1 000 000 was reported [5]. This also serves as a statement of the present error rates that are being experienced in a hospital like ours. The rate of identification errors reported in the literature varies from
