Variation in duplex peak systolic velocity measurement in a multi-site vascular service.

OBJECTIVE: Duplex US (DUS) is increasingly utilised as a first-line investigation for the assessment of carotid disease. For clinical decision-making, DUS assessment must be accurate and reproducible to ensure reliability. We aimed to investigate the variability in peak systolic velocity (PSV) measurement in a multi-site vascular network. METHODS: DUS measurements of PSV were taken from continuous and pulsatile flow, generated by a high fidelity phantom, by 12 experienced vascular scientists across four hospitals. Participants were blinded to the actual PSV value (50 cm/s). RESULTS: We observed an average error of 13.2% (± 8.3) and 11.6% (± 7.5) in PSV measurements taken from pulsatile and continuous waveforms, respectively. Measurements of PSV using the pulsatile waveform demonstrated statistically significant variation across all hospitals; ((hospital/mean) A 43.9 cm/s, B 61.7 cm/s, C 57.4 cm/s, D 47.7 cm/s, p=0.001). Further analysis demonstrated statistically significant variation in 4 instrumentation-related factors when measuring from a pulsatile waveform (Doppler angle, angle of insonation, velocity range, scale range). CONCLUSION: We observed a significant level of error and variation in PSV measurements across four sites within our vascular network. Variation in instrumentation-related factors may be accountable for this. In light of the centralisation of vascular services, it is increasingly important to unify and implement scanning protocols in order to reduce error and inter-site variability.

Achieving good-quality consent: review of literature, case law and guidance.

BACKGROUND: Informed consent is an integral part of clinical practice. There is widespread agreement amongst health professionals that obtaining procedural consent needs to move away from a unidirectional transfer of information to a process of supporting patients in making informed, self-determined decisions. This review aimed to identify processes and measures that warrant consideration when engaging in consent-based discussions with competent patients undergoing elective procedures. METHODS: Formal written guidance from the General Medical Council and Royal College of Surgeons of England, in addition to peer-reviewed literature and case law, was considered in the formulation of this review. RESULTS: A framework for obtaining consent is presented that is informed by the key tenets of shared decision-making (SDM), a model that advocates the contribution of both the clinician and patient to the decision-making process through emphasis on patient participation, analysis of empirical evidence, and effective information exchange. Moreover, areas of contention are highlighted in which further guidance and research are necessary for improved enhancement of the consent process. CONCLUSION: This SDM-centric framework provides structure, detail and suggestions for achieving meaningful consent.

ANTECEDENTES: El consentimiento informado es una parte integral de la práctica clínica. Existe un acuerdo generalizado entre los profesionales de la salud en que lograr el consentimiento del procedimiento no debe ser una transferencia unidireccional de información, sino un proceso de apoyo a los pacientes en la toma de decisiones informadas y autodeterminadas. Esta revisión tiene como objetivo identificar procesos y medidas que deban ser considerados al hablar sobre el consentimiento con pacientes autosuficientes sometidos a procedimientos quirúrgicos electivos. MÉTODOS: Al planear esta revisión se tuvo en cuenta la recomendación formal por escrito del Consejo Médico General y del Royal College of Surgeons of England, además de la literatura revisada por pares y de la jurisprudencia. RESULTADOS: Se presenta un marco para lograr el consentimiento que se basa en los principios clave de la toma de decisiones compartida (Shared Decision-Making, SDM); un modelo que aboga por la contribución, tanto del médico como del paciente, al proceso de toma de decisiones a través del énfasis en la participación del paciente, el análisis de la evidencia empírica y el intercambio efectivo de información. Además, se destacan áreas de contención en las que se necesitan más recomendaciones y más investigación para mejorar aún más el proceso del consentimiento. CONCLUSIÓN: Este marco centrado en la SDM proporciona estructura, detalles y sugerencias sobre cómo se puede lograr un consentimiento informado satisfactorio.

Impaired hyperaemic and rhythmic vasomotor response in type 1 diabetes mellitus patients: a predictor of early peripheral vascular disease.

OBJECTIVES: The smooth muscle of distal vascular networks exhibits periodical contraction and relaxation known as rhythmical vasomotion. The nature of microvascular vasomotion has been shown to correlate with severity of peripheral vascular disease. We present basal and post-ischaemic hyperaemic laser doppler flowmetry vasomotion in control and type 1 adult diabetic patients. DESIGN: Prospective case control study. METHODS: Laser Doppler flowmetry was used to measure vasomotion and hyperaemic responses in age and body mass index matched male subjects (25 type 1 Diabetes Mellitus and 13 controls), all with ankle/brachial pressure index (ABPI) >1.0 but <1.2. RESULTS: The frequency of resting vasomotion was raised in diabetics compared to controls 8 (5-9)min(-1) vs. 5 (4-6)min(-1) (median (range); p<0.0001). The post ischaemic hyperaemia response was significantly higher in the diabetic group compared to the controls 11 (7-12)min(-1) vs. 6 (5-7)min(-1) (median (range); p<0.05). Post ischaemic hyperaemic flux (expressed as percent increase from resting) was significantly lower in the diabetic group compared to controls (234+/-62 vs. 453+/-155%, p<0.01). The time to achieve peak post ischaemic response was also significantly increased in the diabetic group compared to control: 21.4+/-0.4 vs. 12.8+/-5.4sec (mean+/-SD, p<0.05). CONCLUSIONS: Vasomotion frequency and its change during hyperaemic insult is significantly different in Type 1 Diabetes Mellitus subjects compared to controls. The results are similar to patients with macrovascular atherosclerosis. Long term studies of these groups of patients will be required to determine the significance of these findings and whether these changes could be used as a non invasive screening test to predict peripheral early vascular disease in type 1 diabetic patients.

Audit of patient experience of day-case inguinal hernia repair.

BACKGROUND: This study was prompted by a complaint from a patient citing he had suffered postoperative pain and scrotal bruising. We audit postoperative pain following inguinal herniorrhaphy and patient understanding of postoperative complications. METHODS: A telephone survey was carried out to assess patient experience of day-case inguinal herniorrhaphy (DIH). Having identified that there was some dissatisfaction with the outcome of DIH, a prospective audit was carried out to assess causative factors. Changes in practice were made; chiefly, the provision of patient-information leaflets and the standardisation of intraoperative and postoperative analgesia. Repeat audit then assessed the effects of these changes. RESULTS: Ten percent of patients had a poor understanding of postoperative complications following inguinal herniorrhaphy. Thirty-eight percent had early postoperative pain; wound infiltration of local anaesthetic at the end of inguinal herniorrhaphy reduced the incidence of early postoperative pain to 23%. CONCLUSIONS: Audit is an important tool in surgical quality assurance for DIH. Small changes in practice with adherence to good protocols can have a marked effect on patients' experience.

Mapping national surveillance of surgical site infections in England: needs and priorities.

BACKGROUND: The rise in antimicrobial resistance has highlighted the importance of surgical site infection (SSI) prevention with effective surveillance strategies playing a key role in improving patient safety. AIM: To map national needs and priorities for SSI surveillance against current national surveillance activity. METHODS: This study analysed SSI surveillance in National Health Service (NHS) hospitals in England covering 23 surgical procedures. Data collected were: (i) annual number of procedures, (ii) SSI rates from national reports, (iii) national reporting requirement (mandatory, voluntary, not offered), (iv) priority ranking from a survey of 84 English NHS hospitals, (v) excess length of stay and costs from the literature. The relationships between estimated SSI burden, national surveillance activity, and hospital-reported priorities were explored with descriptive and univariate analyses. FINDINGS: Among the 23 surgical categories analysed, top priority ranking by hospitals was associated only with current surveillance (r = 0.76, P < 0.01) and mandatory reporting (33% vs 8 and 4%, P = 0.04). Percentage of hospitals undertaking surveillance, mandatory reporting, and the selection of priorities did not match SSI burden. Large bowel surgery (LBS, voluntary) and caesarean section (not offered) were the two highest contributors of total SSIs per annum, with 39,000 (38%) and 17,000 (16%) respectively, while the four orthopaedic categories (all mandatory) contributed 5000 (5%). LBS also had the highest associated costs (£119 million per annum). CONCLUSION: Current surveillance and future priorities were not associated with SSI rate, volume, or cost to hospitals. The two highest contributors of SSIs and related costs have no (caesarean section) or limited (LBS) coverage by national surveillance.

Differential expression and characterization of proto-oncogene product Ha-Ras GTPase in camel tissues.

Pas proto-oncogene product is known to be involved in transducing signals for growth, differentiation and oncogenesis in mammalian cells. Using a monoclonal antibody to human Ha-Ras, a camel homolog of Ha-Ras protein having an apparent molecular mass of 21 kDa was identified. The expression level of Ha-Ras protein in various tissues of camel was compared with that of mouse tissues. In camel it was found that expression of Ha-Ras protein was highest in the kidney and moderate in the liver. Expression of Ha-Ras in camel lung, testis, spleen, heart, brain, intestine and muscle was found to be very low. While Ha-Ras expression in mouse was found to be highest in the intestine. A moderate expression of Ha-Ras was found in mouse testis, kidney and heart. The kidney tissue extract of camel was immunoprecipitated using the same human Ha-Ras antibody. Biochemical characterization of the immunoprecipitate revealed that like most other G proteins, the camel homolog of Ras is a GTPase. The GTPase activity was found to be stimulated specifically by recombinant human Ras GAP p120 and neurofibromin. It suggests that both camel and human share the same Ras mediated growth signaling process and that human Ras GAP might be able to complement camel Ras GAP function. Camel homolog of Raf-1 and MAP kinase (member of Ras signaling pathway) were also identified by immunoblot. This is the first demonstration showing the existence of a Ras mediated growth signal transduction pathway in camel.

Validation of a novel duplex ultrasound objective structured assessment of technical skills (DUOSATS) for arterial stenosis detection.

INTRODUCTION: Duplex ultrasound facilitates bedside diagnosis and hence timely patient care. Its uptake has been hampered by training and accreditation issues. We have developed an assessment tool for Duplex arterial stenosis measurement for both simulator and patient based training. METHODS: A novel assessment tool: duplex ultrasound assessment of technical skills was developed. A modified duplex ultrasound assessment of technical skills was used for simulator training. Novice, intermediate experience and expert users of duplex ultrasound were invited to participate. Participants viewed an instructional video and were allowed ample time to familiarize with the equipment. Participants' attempts were recorded and independently assessed by four experts using the modified duplex ultrasound assessment of technical skills. 'Global' assessment was also done on a four point Likert scale. Content, construct and concurrent validity as well as reliability were evaluated. RESULTS: Content and construct validity as well as reliability were demonstrated. The simulator had good satisfaction rating from participants: median 4; range 3-5. Receiver operator characteristic analysis has established a cut point of 22/ 34 and 25/ 40 were most appropriate for simulator and patient based assessment respectively. We have validated a novel assessment tool for duplex arterial stenosis detection. Further work is underway to establish transference validity of simulator training to improved skill in scanning patients. CONCLUSIONS: We have developed and validated duplex ultrasound assessment of technical skills for simulator training.

Evaluation of rapid training in ultrasound guided tourniquet application skills.

Tourniquet application has been widely accepted to improve survival for major limb trauma. Colour duplex ultrasound (US) can be used as a non-invasive method of confirming cessation of arterial flow. Participants with no or limited experience of ultrasound were taught to apply the Combat Application Tourniquet with ultrasound guidance. Following this, participants were tested in effective tourniquet application: Blind and with ultrasound guidance. US guidance improved abolition of limb perfusion from 22 to 93 per cent in upper limb; from 25 to 100 per cent in lower limb (p=0.0027 and <0.0001). No significant difference was found in application time for the lower limb; less time was taken for application with US guidance in the upper limb 8.1 (7.1, 8.6) vs 4.5 s (4.0, 5.3; median (IQR)), p=0.002. Tourniquet ultrasound skills are rapidly acquired by novice operators. Accuracy improves with ultrasound guidance, this may have a role in improving survival.

Cytokines in the systemic inflammatory response syndrome: a review.

INTRODUCTION: Patients subject to major surgery, suffering sepsis, major trauma, or following cardiopulmonary bypass exhibit a systemic inflammatory response. This inflammatory response involves a complex array of inflammatory polypeptide molecules known as cytokines. It is well accepted that the loss of local control of the release of these cytokines leads to systemic inflammation and potentially deleterious consequences including the Systemic Inflammatory Response Syndrome, Multi-Organ Dysfunction Syndrome, shock and death. METHODS: The Medline database was searched for literature on mechanisms involved in the development of SIRS and potential targets for modifying the inflammatory response. We focus on the novel therapy of cytokine adsorption as a promising removal technology. RESULTS: Accumulating data from human studies and experimental animal models suggests that both pro- and anti- inflammatory cytokines are released following a variety of initiating stimuli including endotoxin release, complement activation, ischaemia reperfusion injury and others. DISCUSSION: Pro-and anti-inflammatory cytokines interact in a complex and unpredictable manner to influence the immune system and eventually cause multiple end organ effects. Cytokine adsorption therapy provides a potential solution to improving outcomes following Systemic Inflammatory Response Syndrome.

Factors affecting outcome following endoscopic thoracic sympathectomy.

BACKGROUND: Endoscopic thoracic sympathectomy (ETS) is an effective treatment for palmar hyperhidrosis and has been extended to craniofacial symptoms such as blushing and facial sweating. Adverse effects, including compensatory sweating, may cause patients to regret surgery. Such adverse events are currently unpredictable. This study investigated whether age, sex or bodyweight influenced the outcome. METHODS: A total of 110 patients who had bilateral ETS for palmar hyperhidrosis or facial symptoms (blushing or sweating) were asked to complete a questionnaire before and after surgery regarding physical and emotional symptoms, and overall satisfaction. RESULTS: Seventy-nine usable questionnaires were obtained. A decrease (an improvement) in physical symptom score was found in all patients; the median (interquartile range) change was - 15 (-9 to - 18) for facial symptoms and - 8 (-6.75 to - 9) for palmar symptoms. Similarly, there was an improvement in emotional symptom score of - 16 (-8 to - 28) for facial symptoms and - 13 (-7.25 to - 18.5) for palmar symptoms. More compensatory sweating was noted in those treated for facial symptoms (P = 0.007). There was no influence of age, sex or body mass index on outcome. CONCLUSION: ETS is an effective treatment for palmar and facial symptoms. Side-effects may be worse in patients treated for facial symptoms.

United Arab Emirates population data on three DNA tetrameric short tandem repeat loci: HUMTHO1, TPOX and CSF1PO--derived using multiplex polymerase chain reaction and manual typing.

Allele and genotype frequencies for three tetrameric short tandem repeat (STR) loci: HUMTHO1, TPOX, and CSFIPO, were determined in a United Arab Emirates (UAE) national population sample (n = 119). The loci were amplified simultaneously and the PCR products were separated in polyacrylamide DNA sequencing gels. Detection of the DNA fragments was accomplished using silver staining. Allele designations were determined by comparison to an allelic ladder. One allele at each locus was sequenced to confirm the nature of the repeats and their number. Alleles at the HUMTHO1 and TPOX loci were distributed bimodally, while CSF1PO showed unimodal distribution. The observed heterozygosities were 76% for HUMTHO1, 64% for TPOX, and 71% for CSF1PO. No deviation from the Hardy-Weinberg expectations was observed in the genotype distribution for the loci TPOX and CSF1PO, but the HUMTHO1 locus did depart from HWE based on the likelihood ratio and the exact test. No correlation was detected between the alleles at any of the three pairs of loci. The allelic frequency data of these three loci in the UAE population sample can thus be used in human identity testing.