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S Kitchen

Publications and source records attributed to S Kitchen.

At least 19 recordsLinked to original sources
PubMed2005

An evidence-based review and guidelines for patient self-testing and management of oral anticoagulation.

There is a limited evidence base for self-testing and -management for oral anticoagulation management. Available data suggest that these are credible models for a significant minority of patients if underpinned by structured training and follow-up. The guidelines presented are necessarily consensual and outline procedures for patient selection, training, product procurement, product maintenance, quality assurance procedures, dosage adjustment and clinical supervision. The cost-effectiveness of these models remains to be elucidated within the UK. Further data on both health economic and clinical outcomes are required from UK based studies before widespread implementation of self-testing and management can be recommended on a wider scale.

Anticoagulants↗
PubMed2004

SSC/ISTH classification of hemophilia A: can hemophilia center laboratories achieve the new criteria?

To assess the practicality of the recent Scientific and Standardization committee (SSC) of the International Society on Thrombosis and Haemostasis (ISTH) recommendations in respect of the classification of hemophilia we distributed samples from three untreated subjects with hemophilia A to 91 UK hemophilia centers (HCs), comprising 20 comprehensive care centers (CCCs) and 71 HCs. Laboratories were requested to perform their routine factor (F)VIII:C assays and to classify the severity of hemophilia. Median values of < 1 U dL-1 were obtained on two samples. However, for each of the two, approximately 30% of laboratories obtained results in the range 1-29 U dL-1 and 1-33 U dL-1 respectively. For one of these samples 17 laboratories diagnosed severe hemophilia despite obtaining FVIII:C levels in the range 1-5 U dL-1. The median FVIII:C for the third sample was 5.8 U dL-1 with a range of 1.5-36 U dL-1. For this sample eight centers diagnosed severe hemophilia. Fifty-four laboratories obtained a result > 5 U dL-1; 21 of these diagnosed mild hemophilia, 31 moderate hemophilia and two severe hemophilia. Results from CCCs were more accurate and more precise than those from HCs. Our results indicate a need for improved standardization of FVIII assays. In the UK there remains a lack of consensus in respect of the laboratory diagnostic criteria for the classification of hemophilia A.

Clinical Laboratory Techniques↗
PubMed2004

The rare coagulation disorders--review with guidelines for management from the United Kingdom Haemophilia Centre Doctors' Organisation.

The rare coagulation disorders are heritable abnormalities of haemostasis that may present significant difficulties in diagnosis and management. This review summarizes the current literature for disorders of fibrinogen, and deficiencies of prothrombin, factor V, FV + VIII, FVII, FX, the combined vitamin K-dependent factors, FXI and FXIII. Based on both collective clinical experience and the literature, guidelines for management of bleeding complications are suggested with specific advice for surgery, spontaneous bleeding, management of pregnancy and the neonate. We have chosen to include a section on Ehlers-Danlos Syndrome because haematologists may be consulted about bleeding manifestations in such patients.

Afibrinogenemia↗
PubMed2003

The PIVKA II test: the first reliable coagulation test for autopsy investigations.

To date there is no routinely used reliable diagnostic test that can be performed in the post-mortem period to investigate whether a deceased had a coagulation disorder. This paper describes a series of experiments to assess the use of an antigen-based method to investigate the vitamin K-dependent factor II function in the deceased. It illustrates that by using this approach the functional status of factor II can be investigated in the post-mortem period. The abnormal proteins that are investigated by this method appear to remain stable for at least 72 h and potentially up to at least 7 days. The method that is illustrated could thus be reliably used in the post-mortem period to identify a natural or drug-induced factor II abnormality. The potential for other protein components of the coagulation cascade to be investigated by similar antigen-based methodology is suggested.

Aged↗
PubMed2003

Patient self-management of oral anticoagulation and external quality assessment procedures.

The role of external quality assessment (EQA) is a contentious issue for patient self-management (PSM) of oral anticoagulation. Patients from general practices in the West Midlands undertaking PSM were recruited to compare efficacy of patients' and health professionals' EQA procedure using the UK National External Quality Assessment Scheme (NEQAS). Patients using Coaguchek (Roche Diagnostics) were trained to perform EQA as part of their PSM training. They undertook PSM for 26 weeks and were asked to perform EQA using material provided by the UK NEQAS twice at home without supervision and twice at the practice with supervision. Patients' results were compared with health care professional users of Coaguchek S. Twenty-three PSM patients were compared with 75 health care professional users of the NEQAS scheme. The PSM group international normalized ratio (INR) percentage time in range was 74%. There was no significant difference in the median results on NEQAS samples obtained by the patients and those obtained by professionals. Three patients were outwith consensus (results > 15% from the median INR) on more than one occasion. Patients were able to perform the EQA tests competently. The data show that good agreement can be achieved between patients analysing the same EQA samples, with coefficients of variation ranging from 22.3% to as low as 5.4%. Further study is required to determine how precision within these EQA schemes relates to the stability of treatment in patients' management of their own anticoagulation.

Administration, Oral↗
PubMed2003

Problems relating to the laboratory diagnosis of factor XIII deficiency: a UK NEQAS study.

Familial (F)XIII deficiency is an extremely rare bleeding disorder. In most laboratories the diagnosis is initially established through a clot-solubility screening test. We report here results from a series of UK NEQAS (Blood Coagulation). Proficiency Testing investigations, in which laboratories were provided with samples from normal individuals and from various subjects with FXIII deficiency with a request to perform their usual test for this disorder and to provide an interpretation of their results. Over 95% of centers were able to diagnose severe familial FXIII deficiency in previously untreated patients and to identify samples from normal subjects. However, both quantitative and qualitative methods produced widely variable results on samples obtained from previously treated individuals with FXIII deficiency but having measurable levels of FXIII. Data generated by UK NEQAS investigations suggested that solubility tests employing thrombin show greater sensitivity to FXIII deficiency, and this was confirmed in a subsequent single-center study. Our results lead us to recommend the use of thrombin and acetic acid in the clot-solubility screening test. Use of sensitive screening tests, and improvement in the accuracy and precision of quantitative FXIII assays will aid study of the clinical importance of moderate FXIII deficiency.

Acetic Acid↗
PubMed2002

Rapid reversal of oral anticoagulation with warfarin by a prothrombin complex concentrate (Beriplex): efficacy and safety in 42 patients.

Beriplex, a prothrombin complex concentrate (PCC), was administered to 42 patients requiring immediate reversal of their oral anticoagulant therapy. The dose administered was determined using the pretreatment International Normalized Ratio (INR). Blood samples were obtained before treatment and at 20, 60 and 120 min after treatment. The following investigations were performed on all samples - INR, clotting factors II, VII, IX and X, coagulation inhibitors protein C (PC) and antithrombin (AT), and other markers of disseminated intravascular coagulation, plasma fibrinogen, D-dimer and platelet count. Immediate reversal of the INR, the vitamin K-dependent clotting factors and PC was achieved in virtually all patients. Reduced AT levels were present in 18 patients before treatment. Further slight AT reductions occurred in four patients, but other associated abnormalities of haemostasis were observed in only one of the four patients. One patient with severe peripheral vascular disease, sepsis and renal and cardiac failure died of a thrombotic stroke following leg amputation, 48 h after receiving Beriplex. No other arterial and no venous thromboembolic events occurred within 7 d of treatment. Beriplex is effective in rapidly reversing the anticoagulant effects of warfarin, including PC deficiency, without inducing coagulation activation. Caution should continue to be exercised in the use of these products in patients with disseminated intravascular coagulation, sepsis or liver disease.

Adult↗
PubMed2002

A performance evaluation of commercial fibrinogen reference preparations and assays for Clauss and PT-derived fibrinogen.

The wide availability of fibrinogen estimations based on the prothrombin time (PT-Fg) has caused concern about the variability and clinical utility of fibrinogen assays. In a multi-centre study, we investigated fibrinogen assays using various reagents and analysers. Clauss assays generally gave good agreement, although one reagent gave 15-30% higher values in DIC and thrombolysis. Two commercial reference preparations had much lower potencies than the manufacturers declared, and plasma turbidity influenced parallelism in some Clauss assays. PT-Fg assays gave higher values than Clauss and showed calibrant dependent effects, the degree of disparity correlating with calibrant and test sample turbidity. Analyser and thromboplastin dependent differences were noted. The relationship between Clauss and PT-Fg assays was sigmoid, and the plateau of maximal PT-Fg differed by about 2 g/l between reagents. ELISA and immunonephelometric assays correlated well, but with a high degree of scatter. Antigen levels were higher than Clauss, but slightly lower than PT-Fg assays, which appeared to be influenced by degraded fibrinogen. Clauss assays are generally reproducible between centres, analysers and reagents, but PT-Fg assays are not reliable in clinical settings.

Blood Coagulation Tests↗
PubMed2000

Effect of pulse repetition rate on the perception of thermal sensation with pulsed shortwave diathermy.

BACKGROUND AND PURPOSE: Pulsed shortwave diathermy (PSWD) is a form of therapy commonly used to enhance tissue repair and reduce pain. It is normally considered to be an athermal form of treatment; however, there is some evidence to suggest that thermal effects can arise with adequate dosage. The purpose of this study was to determine the pulse repetition rate (PRR) required to generate a 'possible' and 'definite' thermal sensation when PSWD was applied to the thigh. METHOD: Thirty healthy subjects were randomly assigned to placebo or treatment groups. The treatment group was exposed to PSWD at a constant setting of pulse duration (400 microseconds) and pulse power (190 W) while the PRR was increased from 26 Hz to 400 Hz in 10 increments. Each dose was applied for a period of two minutes. At the end of each application, subjects were asked if they felt a (1) 'possible' or (2) 'definite' thermal sensation. Skin temperature was measured immediately after each application. Placebo subjects were exposed to PSWD at its lowest settings throughout the experiment (pulse power = 5 W; pulse duration = 65 microseconds and PRR = 26 Hz). RESULTS: The results showed a significant correlation (p < 0.048) between PRR at 'definite' thermal sensation and skin temperature post-treatment and PRR at 'possible' thermal sensation (p < 0.001). Mean skin temperature increased significantly as PRR was increased, from 28.69 (+/- 0.75) degrees C pre-treatment to 31.14 (+/- 1.04) degrees C post-treatment, a mean difference of 2.34 degrees C. CONCLUSIONS: These results suggest that PSWD at adequate dosages can generate thermal effects, and that there is a relationship between these thermal effects and the PRR used. These results may have significant implications for the safe use of PSWD in the clinical arena.

Adult↗
PubMed2000

Effect of positioning on respiratory synchrony in non-ventilated pre-term infants.

BACKGROUND AND PURPOSE: Body position can play an important role in an infant's recovery from respiratory disease, but few studies have accounted for sleep state which is known to have a direct influence on the control of respiratory muscles as well as on metabolic and circulatory changes. The purpose of this study was to examine the influence of body position on respiratory function in pre-term infants whilst accounting for sleep state. METHOD: Thoraco-abdominal motion was assessed using respiratory inductance plethysmography (RIP) to provide measures of relative rib cage (RC) and abdominal (AB) movement in ten non-ventilated pre-term infants. Continuous measurements of oxygen saturation (SaO2), pulse and heart rate (HR), were made and sleep state was recorded using behavioural criteria and electro-oculogram (EOG) measurements. RESULTS: The results showed a significant increase in HR in supine, but no significant difference in SaO2 as a function of position, compared to the prone position where a significant reduction was found in thoraco-abdominal asynchrony for both groups and a reduction in variability in both HR and SaO2. Intra-subject variability of thoraco-abdominal motion as a function of position demonstrated no significant difference on return to supine or on return to prone, illustrating good repeatability of measures. CONCLUSIONS: Prone positioning of pre-term infants recovering from respiratory disease may improve respiratory function. As measured, the improvement in respiratory synchrony in prone position brings pre-term infants' breathing pattern into line with that expected in term infants.

Cross-Over Studies↗
PubMed2000

The effect of dietary supplements on the nPCR in stable hemodialysis patients.

OBJECTIVE: To investigate whether (1) dietary supplements raise the normalized protein catabolic rate (nPCR) and/or further improve the nutritional status of stable hemodialysis patients who have both a low nPCR and a low dietary protein intake, <1.2 g/kg body weight/day; and if (2) protein intake measured by nPCR reflects protein intake measured by estimated food diaries in stable patients. DESIGN: Prospective experimental study with a single intervention group. SETTING: Hospital outpatient hemodialysis unit. SUBJECTS: Seventeen stable chronic hemodialysis patients (10 men, 7 women) were studied over 8 months. INTERVENTION: Subjects with both a low nPCR and dietary protein intake <1.2 g/kg body weight/day received dietary supplements for the first 2 months. Measurements to assess protein intake and nutritional status were taken at baseline and repeated at the end of 2 months, and at 6 months postintervention. MAIN OUTCOME MEASURE: nPCR, dietary protein intake using 7-day estimated food diaries, serum urea, serum albumin, serum creatinine, serum bicarbonate, dialysis adequacy (Kt/V), and body mass index (BMI). RESULTS: Dietary supplements significantly increased both the nPCR and the total protein intake at 2 months (1.21 +/- 0.26, 1.10 +/- 0.12, respectively) compared with baseline (0.95 +/- 0.18, 0.75 +/- 0.19, respectively) and 8 months (0.99 +/- 0.12, 0.78 +/- 0.21, respectively), P <.0001, respectively. There was no change in the nutritional status of the subjects. There was a significant difference between the nPCR and the dietary protein intake at baseline, P <.004; at 2 months, P <.047; and at 8 months, P <.001. CONCLUSION: Dietary supplements can significantly increase the nPCR and dietary protein intake in stable hemodialysis patients with a low nPCR and dietary protein intake. Because a low nPCR is associated with a high morbidity and mortality rate, it may be prudent to supplement such patients. The use of the nPCR to quantify dietary protein intake in stable hemodialysis patients should be used with caution.

Aged↗