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2.
Med J Malaysia ; 70(4): 228-31, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26358019

RESUMEN

INTRODUCTION: T-piece resuscitator (TPR) has many advantages compared to self-inflating bag (SIB). Early Continuous Positive Airway Pressure (CPAP) during newborn resuscitation (NR) with TPR at delivery can reduce intubation rate. METHODS: We speculated that the intubation rate at delivery room was high because SIB had always been used during NR and this can be improved with TPR. Intubation rate of newborn <24 hours of life was deemed high if >50%. An audit was carried out in June 2010 to verify this problem using a check sheet. RESULTS: 25 neonates without major congenital anomalies who required NR with SIB at delivery were included. Intubation rate of babies <24 hours of life when SIB was used was 68%. Post-intervention audit (August to November 2010) on 25 newborns showed that the intubation rate within 24 hours dropped to 8% when TPR was used. Proportion of intubated babies reduced from 48.3% (2008-2009) to 35.1% (2011-2012), odds ratio 0.58 (95% CI 0.49-0.68). Proportion of neonates on CPAP increased from 63.5% (2008-2009) to 81.0% (2011-2012), odds ratio 2.44 (95% CI 2.03-2.93). Mean ventilation days fell to below 4 days after 2010. Since then, all delivery standbys were accompanied by TPR and it was used for all NR regardless of settings. There was decline in intubation rate secondary to early provision of CPAP with TPR during NR. Mean ventilation days, mortality and length of NICU stay were reduced. CONCLUSION: This practice should be adopted by all hospitals in the country to achieve Millennium Development Goal 4 (2/3 decline of under 5 mortality rate) by 2015.

4.
Clin Nephrol ; 76(5): 412-6, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22000563

RESUMEN

We report a 79-year-old woman with a left side simple renal cyst invaded by infiltrating urothelial carcinoma mimicking a Bosniak Class IV renal cyst. Computerized tomography has high accuracy for the diagnosis of renal cysts and urothelail carcinoma. But, in this case it was still difficult to distinguish a simple renal cyst with infiltrating urothelial carcinoma invasion from a Bosniak Class IV renal cyst on CT scan. The management of a Bosniak Class IV renal cyst and urothelail carcinoma is totally different. Therefore, we performed a left side nephroureterectomy. This patient will have regular follow-up with cystoscopy every 3 months for the first 2 y, every 6 months for the next 2 y, and then annually thereafter.


Asunto(s)
Carcinoma de Células Transicionales/diagnóstico por imagen , Enfermedades Renales Quísticas/diagnóstico por imagen , Neoplasias Renales/diagnóstico por imagen , Anciano , Carcinoma de Células Transicionales/patología , Carcinoma de Células Transicionales/cirugía , Diagnóstico Diferencial , Femenino , Humanos , Enfermedades Renales Quísticas/patología , Enfermedades Renales Quísticas/cirugía , Neoplasias Renales/patología , Neoplasias Renales/cirugía , Invasividad Neoplásica , Nefrectomía/métodos , Radiografía
5.
Anaesthesia ; 66(11): 999-1005, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21883124

RESUMEN

Mild hypothermia (34-35 °C) increases peri-operative blood loss. We have previously demonstrated the beneficial effect of in vitro desmopressin on impairment of primary haemostasis associated with hypothermia. This study evaluated subcutaneous desmopressin in 52 healthy volunteers, randomly assigned to receive either normal saline or desmopressin 1.5, 5 or 15 µg (with 13 in each group). Blood samples were collected before and 2 h after drug administration and incubated at 32 and 37 °C. Platelet function analyser PFA-100(®) closure times were measured. Hypothermia at 32 °C prolonged mean (95% CI) closure times (for adenosine diphosphate/collagen by 11.3% (7.5-15.2%) and for adrenaline/collagen by 16.2% (11.3-21.2%); these changes were reversed by desmopressin. A very small dose was found to be effective (1.5 µg); this dose did not significantly change closure times at 37 °C, but fully prevented its prolongation at 32 °C. Subcutaneous desmopressin prevents the development of hypothermia-induced impairment of primary haemostasis.


Asunto(s)
Desamino Arginina Vasopresina/farmacología , Hemostasis/efectos de los fármacos , Hipotermia/sangre , Adulto , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino
6.
Br J Anaesth ; 107(3): 430-7, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21685111

RESUMEN

BACKGROUND: Dexmedetomidine (DEX) is an alpha 2-adrenoreceptor agonist, which induces sedation and analgesia. This study aimed to determine whether intranasal DEX offered perioperative sedation and better postoperative analgesia. METHODS: Patients having unilateral third molar surgery under local anaesthesia were recruited and allocated to receive either intranasal DEX 1 µg kg(-1) (Group D) or same volume of saline (Group P) 45 min before surgery. Patient-controlled sedation with propofol was offered as a rescue sedative. Perioperative sedation, postoperative pain relief and analgesic consumption, vital signs, adverse events, postoperative recovery, and satisfaction in sedation and analgesia were assessed. RESULTS: Thirty patients from each group were studied. Areas under curve (AUC) of postoperative numerical rating scale (NRS) pain scores 1-12 h at rest and during mouth opening were significantly lower in Group D (P=0.003 and 0.009, respectively). AUC BIS values and OAA/S sedation scores were significantly lower before surgery and at the recovery area (all P<0.01) with significantly less intra-operative propofol used in group D (P<0.01). In group D, heart rate was significantly lower at recovery period (P=0.005) while systolic blood pressure in different periods of the study (all P<0.01), but the decreases did not require treatment. More patients from placebo group experienced dizziness (P=0.026) but no serious adverse event was found. No difference was found in postoperative psychomotor recovery and satisfaction in pain relief and sedation. CONCLUSIONS: Patients receiving intranasal DEX for unilateral third molar surgery with local anaesthesia were more sedated perioperatively with better postoperative pain relief. No delay in psychomotor recovery was seen.


Asunto(s)
Agonistas de Receptores Adrenérgicos alfa 2/farmacología , Analgésicos no Narcóticos/farmacología , Anestesia Local , Dexmedetomidina/farmacología , Hipnóticos y Sedantes/farmacología , Tercer Molar/cirugía , Dolor Postoperatorio/tratamiento farmacológico , Administración Intranasal , Adolescente , Adulto , Área Bajo la Curva , Dexmedetomidina/administración & dosificación , Dexmedetomidina/efectos adversos , Femenino , Humanos , Masculino
7.
Br J Cancer ; 103(6): 852-60, 2010 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-20736946

RESUMEN

BACKGROUND: Parvin-beta (ParvB), a potential tumour suppressor gene, is a focal adhesion protein. We evaluated the role of ParvB in the upper urinary tract urothelial cell carcinoma (UUT-UC). METHODS: ParvB mRNA and proteins levels in UUT-UC tissue were investigated by quantitative real-time polymerase chain reaction and western blot analysis, respectively. In addition, the expression of ParvB in tissues from patients with UUT-UC at different stages was evaluated by immunohistochemistry. Furthermore, biological functions of ParvB in urothelial cancer cells were investigated using a doxycycline-inducible overexpression system and siRNA. RESULTS: Western blot and mRNA analysis showed downregulation of ParvB expression in frozen UUT-UC tissue. Immunohistochemistry revealed high staining intensity of ParvB in normal urothelium, which decreased markedly at advanced stages of UUT-UC (P=0.0000). Moreover, ParvB was an independent prognostic indicator for disease-specific survival of patients with UUT-UC. Functional assays indicated that overexpression of ParvB in an urothelial cancer cell line resulted in decreased cell growth rate and ability to migrate. In contrast, knockdown of ParvB expression increased cell migration ability. CONCLUSIONS: Downregulation of ParvB expression significantly increased urothelial cancer cell growth and migration. Downexpression of ParvB level in UUT-UC correlated with tumour stage, and was an independent unfavourable prognostic factor for disease-specific survival of patients with UUT-UC.


Asunto(s)
Actinina/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias de la Vejiga Urinaria/metabolismo , Urotelio/patología , Actinina/química , Actinina/genética , Secuencia de Bases , Western Blotting , División Celular/fisiología , Movimiento Celular/fisiología , Cartilla de ADN , Técnicas de Silenciamiento del Gen , Humanos , Inmunohistoquímica , Pronóstico , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Supervivencia , Neoplasias de la Vejiga Urinaria/patología
8.
Br J Anaesth ; 102(6): 779-84, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19411670

RESUMEN

BACKGROUND: The usefulness of the PFA-100 in assessing the risk of bleeding in non-cardiac surgery is not clear. This study aims to examine this by correlating preoperative PFA-100 measurement with perioperative bleeding in patients receiving cyclooxygenase (COX) inhibitors. METHODS: PFA-100 with adenosine-5'-diphosphate (ADPCT) and epinephrine (EPICT) cartridges were measured before operation in consecutive patients undergoing elective total knee replacement and taking different COX inhibitors. Surgery and anaesthesia were performed by the same team using standardized techniques. Intraoperative blood loss and postoperative drain output were recorded by anaesthetists and nurses blinded to the PFA-100 measurements. Surgeons, similarly blinded, were asked to rate the quality of haemostasis. Correlation was sought between these data and PFA-100 measurements. RESULTS: Thirty patients were studied, involving 51 knees. Preoperative PFA-100 EPICT was correlated with drain output (r=0.30, P=0.03). The correlation becomes stronger when a 20% in vitro haemodiluted sample was used for measurement (r=0.42, P=0.01). Receiver-operating characteristic curve analysis using the diluted measurements [area under curve (AUC) 0.74 (95% CI 0.54-0.94)] suggested using a cut-off value of 188 s for EPICT, which will predict excessive drain output with 89% sensitivity, 54% specificity, and a likelihood ratio of 1.93. Diluted EPICT was also correlated with surgeon rating of haemostasis (r=0.36, P=0.04) although none of the measurements correlated with intraoperative blood loss. CONCLUSIONS: Preoperative PFA-100 prolongation is correlated with increased postoperative drain output. It can be a potentially useful preoperative measurement in patients taking COX inhibitors.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Inhibidores de la Ciclooxigenasa/efectos adversos , Pruebas de Función Plaquetaria/métodos , Hemorragia Posoperatoria/sangre , Cuidados Preoperatorios/métodos , Anciano , Antropometría , Pérdida de Sangre Quirúrgica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas de Función Plaquetaria/instrumentación , Sistemas de Atención de Punto , Hemorragia Posoperatoria/inducido químicamente , Pronóstico , Medición de Riesgo/métodos , Método Simple Ciego
9.
J Pathol ; 214(3): 387-93, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18085521

RESUMEN

Perivascular epithelioid cell tumours (PEComas) are a family of tumours including classic angiomyolipoma, lymphangioleiomyomatosis, and clear epithelioid cell tumours reported under a variety of names such as epithelioid angiomyolipoma, pulmonary and extrapulmonary clear cell sugar tumour, and PEComa. Our previous comparative genomic hybridization study of PEComas demonstrated recurrent chromosomal aberrations including deletions on chromosome 16p, where the TSC2 gene is located. In this study, we focused on the alteration of chromosome 16p, including TSC2. We collected ten sporadic and two tuberous sclerosis complex-associated PEComas, as well as 14 sporadic classic hepatic and renal angiomyolipomas (AMLs) as controls. We used 16 microsatellite markers distributed along chromosome 16p to test for allelic imbalances on chromosome 16p and at TSC2, and two markers for TSC1. Furthermore, we carried out immunohistochemical staining for phospho-p706K, phospho-AKT, and phospho-S6 to evaluate the effect of TSC2 alterations on the mTOR signalling pathway. Loss of heterozygosity (LOH) was found in 11 PEComas and involved the region of the TSC2 locus in seven. Six classic angiomyolipomas had allelic changes at chromosome 16p. Microsatellite instability was detected in two PEComas. The incidence of genetic aberrations was significantly higher in the PEComa group. Only one PEComa showed LOH at the TSC1 locus. Eleven PEComas and 13 AMLs revealed elevated phospho-p70S6K accompanied by reduced phospho-AKT. Five PEComas and eight classic angiomyolipomas were positive for phospho-S6. The phosphorylation profile indicates functional activation of the mTOR pathway through a disrupted TSC1/2 complex. Our observations of frequent deletion of TSC2 and the mTOR signalling pathway provide evidence that the oncogenetic lineage of PEComa, as a distinct TSC2-linked neoplasm, is similar to that of angiomyolipoma.


Asunto(s)
Angiomiolipoma/genética , Biomarcadores de Tumor , Neoplasias Renales/genética , Proteínas Supresoras de Tumor/genética , Adolescente , Adulto , Alelos , Estudios de Casos y Controles , Niño , Mapeo Cromosómico , Femenino , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/genética , Pérdida de Heterocigocidad , Masculino , Inestabilidad de Microsatélites , Persona de Mediana Edad , Proteínas Quinasas/genética , Serina-Treonina Quinasas TOR , Proteína 2 del Complejo de la Esclerosis Tuberosa
10.
Anaesthesia ; 62(11): 1132-8, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17924894

RESUMEN

This randomised, double-blind study compared dexmedetomidine and midazolam for intravenous sedation during third molar surgery under local anaesthesia. Sixty patients received either dexmedetomidine (up to 1 microg x kg(-1)) or midazolam (up to 5 mg), which was infused until the Ramsay Sedation Score was four or the maximum dose limit was reached. Intra-operative vital signs, postoperative pain scores and analgesic consumption, amnesia, and satisfaction scores for patients and surgeons, were recorded. Sedation was achieved by median (IQR (range)) doses of 47 microg (39-52 (25-76)) or 0.88 microg x kg(-1) (0.75-1.0 (0.6-1.0)) dexmedetomidine, and 3.6 mg (3.3-4.4 (1.9-5.0)) or 0.07 mg x kg(-1) (0.055-0.085 (0.017-0.12)) midazolam. Heart rate and blood pressure during surgery were lower in dexmedetomidine group. There was no significant difference in satisfaction or pain scores. Midazolam was associated with greater amnesia. Dexmedetomidine produces comparable sedation to midazolam.


Asunto(s)
Sedación Consciente/métodos , Dexmedetomidina , Hipnóticos y Sedantes , Midazolam , Tercer Molar/cirugía , Adulto , Anestesia Local/métodos , Presión Sanguínea/efectos de los fármacos , Método Doble Ciego , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Dolor Postoperatorio , Satisfacción del Paciente , Extracción Dental , Diente Impactado/cirugía
11.
Arch Androl ; 51(6): 419-24, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16214726

RESUMEN

Prostate stromal sarcoma is quite rare, comprising only 0.1-0.2% of all prostate cancers. Here, we report one case of prostate stromal sarcoma in a 38-year-old man. Initially, the patient suffered from lower urinary tract symptoms, and intravenous pyelography showed a larger filling defect in the bladder. Transrectal ultrasound showed a huge heterogenous mass between the bladder and rectum. Abdominal computed tomography revealed prostate tumor with local invasion. Radical cystoprostatectomy with ileal conduit was performed; pathology revealed high-grade prostate stromal sarcoma with invasion to the right seminal vesicle and urethra. This article describes the pathology and immunohistrochemical features of this case and briefly reviews the literature.


Asunto(s)
Neoplasias de la Próstata/patología , Sarcoma/patología , Adulto , Antígenos CD34/análisis , Terapia Combinada , Humanos , Inmunohistoquímica , Masculino , Prostatectomía , Neoplasias de la Próstata/química , Neoplasias de la Próstata/terapia , Sarcoma/química , Sarcoma/terapia
12.
Arch Androl ; 51(4): 295-8, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16036637

RESUMEN

This is a report of a 70-year-old man with malignant phyllodes tumor of prostate. The retropubic prostatectomy was done. The stroma of the tumor was cellular and composed of elongated cells with spindle shaped nuclei and fragmented bizarre giant cells. After recovery from surgery, prophylatic radiotherapy was given over 2 months. A case report of a patient treated at our medical center and a review of the literature was done.


Asunto(s)
Adenocarcinoma/patología , Tumor Filoide/patología , Neoplasias de la Próstata/patología , Adenocarcinoma/cirugía , Anciano , Humanos , Masculino , Tumor Filoide/cirugía , Neoplasias de la Próstata/cirugía , Células del Estroma/patología , Resultado del Tratamiento
13.
Ann Clin Biochem ; 42(Pt 1): 73-7, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15802039

RESUMEN

Phaeochromocytoma or paraganglioma that exclusively secretes dopamine is very rare. This case illustrates its atypical presentation and the importance of interpretative reporting for urine catecholamines leading to the diagnosis and subsequent management of a patient with this condition. We report a 71-year-old Chinese woman with a large dopamine-secreting paraganglioma. She presented with low back pain for six months. On examination, a right abdominal mass was palpable incidentally. Her blood pressure was normal throughout. Serial 24-h urine collections for catecholamines showed enormous elevation of urine dopamine excretion to 80.7 micromol/day (normotensive:<2.6 m mol/day). However, the daily excretions of urine adrenaline and noradrenaline, as well as their metabolites were within their respective reference intervals. Good communication between chemical pathologists and physicians prompted the arrangement of the whole body 131I-meta-iodobenzylguanidine (MIBG) scintigraphy, which showed a large signal in the right upper quadrant of the abdomen corresponding to a large extra-adrenal tumour detected by both ultrasonography and computerized tomography (CT) of the abdomen. Histological section of the tumour tissue revealed paraganglioma, which stained positive for chromogranin and neuron-specific enolase. After four months, the patient presented with chest symptoms and CT of the thorax revealed multiple nodules. Lung metastases were suspected. However, follow-up urine catechola- mine and dopamine excretions were again within their respective normotensive reference intervals. A second MIBG scintigraphy was performed, but no specific uptake at either the thorax or the abdomen could be demonstrated. Fine-needle aspiration cytology using the thoracoscopic technique was performed and immunochemical staining of the biopsy specimen showed the presence of non- small-cell carcinoma of the lung.


Asunto(s)
Dopamina/metabolismo , Epinefrina/orina , Norepinefrina/orina , Paraganglioma/diagnóstico , 3-Yodobencilguanidina , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Neoplasias de las Glándulas Suprarrenales/metabolismo , Anciano , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/secundario , Femenino , Humanos , Radioisótopos de Yodo , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Paraganglioma/metabolismo , Tomografía Computarizada por Rayos X
14.
Ann Clin Biochem ; 41(Pt 6): 482-4, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15588439

RESUMEN

BACKGROUND: Roche Diagnostics has issued new c-fas calibrators for its automated systems. These produce creatinine values that are more comparable with those obtained by high-performance liquid chromatography. However, this results in an underestimation of measured creatinine at concentrations below 155 micromol/L and an overestimation at concentrations above this value. METHODS: Serum and urine creatinine concentrations were prospectively determined on samples from 60 patients using the new (compensated) and old (uncompensated) c-fas calibrators, and Passing-Bablok regression analysis was performed. The regression equations thus determined were then used retrospectively to determine the compensated creatinine results (i.e. those results that would have been obtained using the new calibrator) in those serum and urine samples analysed in the previous year using the old uncompensated c-fas calibrator. The compensated creatinine results were then used to estimate the glomerular filtration rate (GFR) by calculating creatinine clearance. This was done by using the formula: UV/Pt, in which U represents the urinary creatinine concentration (micromol/L), V the urinary collection volume (mL), P the serum creatinine concentration (micromol/L) and t the urinary collection time (min). It was also calculated using the abbreviated Modification of Diet in Renal Disease study group (MDRD) formula. RESULTS: The creatinine clearance as determined using either the UV/Pt calculation or the MDRD formula overestimated GFR by approximately 30% and approximately 50%, respectively, in normal individuals with a serum creatinine concentration below 155 micromol/L. However, in patients with mild to moderate renal failure (serum creatinine from 155 to 500 micromol/L), changes in creatinine clearances determined by the two procedures were minimal. CONCLUSION: When laboratories introduce this new, compensated calibrator into practice, it may be appropriate to discuss its potential impact with clinical staff who monitor patients using creatinine clearance.


Asunto(s)
Creatinina/sangre , Creatinina/orina , Tasa de Filtración Glomerular , Enfermedades Renales/sangre , Enfermedades Renales/orina , Tasa de Depuración Metabólica , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Calibración , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Proteínas Proto-Oncogénicas c-fos/análisis , Estándares de Referencia , Estudios Retrospectivos
15.
Anaesth Intensive Care ; 32(5): 630-6, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15535484

RESUMEN

A retrospective analysis of 413 patients who received postoperative epidural analgesia under a standardized protocol found that 84 (20%) had a duration of epidural catheterization of greater than four days. The most common reasons were significant pain (n=64, 15%) and coagulopathy (n=26, 6%). Risk factor analysis for coagulopathy showed an odds ratio of 10.1 (95% confidence interval 4.2-24.5) for prolonged epidural catheterization among patients undergoing hepatectomy. Magnetic resonance imaging, performed in four patients with clinical signs suggestive of epidural haematoma, was negative for a space-occupying lesion in all cases. Eleven patients developed fever and clinical signs suggestive of epidural catheter-related infection, necessitating early catheter removal. Sixteen patients had persistent lower limb weakness at 24 hours after catheter removal. The signs soon resolved in all except two, one of whom had neuropathy related to intraoperative positioning and the other preoperative weakness. Accidental epidural catheter dislodgement occurred in 29 patients (7%) and is potentially hazardous if coagulopathy is unresolved. The risk-benefit ratio and factors complicating catheter removal, especially coagulopathy, should be considered when deciding whether to use epidural techniques.


Asunto(s)
Analgesia Epidural/instrumentación , Trastornos de la Coagulación Sanguínea/etiología , Remoción de Dispositivos/efectos adversos , Dolor Postoperatorio/prevención & control , Adulto , Anciano , Anciano de 80 o más Años , Analgesia Epidural/efectos adversos , Analgesia Epidural/métodos , Análisis de Varianza , Trastornos de la Coagulación Sanguínea/epidemiología , Cateterismo/efectos adversos , Femenino , Estudios de Seguimiento , Hospitales Universitarios , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Dolor Postoperatorio/terapia , Periodo Posoperatorio , Probabilidad , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Tasa de Supervivencia , Factores de Tiempo
17.
Clin Biochem Rev ; 24(1): 3-12, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-18568044

RESUMEN

This mini-review provides a general understanding of electrospray ionisation mass spectrometry (ESI-MS) which has become an increasingly important technique in the clinical laboratory for structural study or quantitative measurement of metabolites in a complex biological sample. The first part of the review explains the electrospray ionisation process, design of mass spectrometers with separation capability, characteristics of the mass spectrum, and practical considerations in quantitative analysis. The second part then focuses on some clinical applications. The capability of ESI-tandem-MS in measuring bio-molecules sharing similar molecular structures makes it particularly useful in screening for inborn errors of amino acid, fatty acid, purine, pyrimidine metabolism and diagnosis of galactosaemia and peroxisomal disorders. Electrospray ionisation is also efficient in generating cluster ions for structural elucidation of macromolecules. This has fostered a new and improved approach (vs electrophoresis) for identification and quantification of haemoglobin variants. With the understanding of glycohaemoglobin structure, an IFCC reference method for glycohaemoglobin assay has been established using ESI-MS. It represents a significant advancement for the standardisation of HbA1c in diabetic monitoring. With its other applications such as in therapeutic drug monitoring, ESI-MS will continue to exert an important influence in the future development and organisation of the clinical laboratory service.

18.
Anaesth Intensive Care ; 30(4): 442-8, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12180582

RESUMEN

Neurolytic celiac plexus block is a recognised treatment for visceral abdominal pain due to malignancy. The need for a diagnostic celiac plexus block prior to neurolytic blockade is of questionable value, as it may not predict a positive response and may incorrectly predict a lack of response. Our objective is to evaluate the efficacy of diagnostic celiac plexus block. The records of 59 patients treated with celiac plexus block during 1994-2000 were retrospectively reviewed. Diagnostic block was performed on 32 patients prior to the decision for subsequent neurolytic block (Group 1). Another 27 patients were directly treated with a neurolytic celiac plexus block (Group 2). Response of Group 1 to diagnostic and neurolytic blocks was compared. Data from Group 2 was used to project the response of Group 1 should those patients with negative response to diagnostic block proceeded to neurolytic block. A two-by-two table was then constructed. The diagnostic celiac plexus block predicted a positive response with a sensitivity of 93% and a specificity of 37%. The positive predictive value was 85% and the negative predictive value was 58%. The estimated "number needed to test" before a "true" nonrespondent to lytic block to be detected was 16.7. Therefore, a positive response to diagnostic block correlates positively with neurolytic celiac plexus block for abdominal visceral pain due to malignancy. However, diagnostic block is a poor predictor when the response is negative. Hence, its clinical role is questionable and may not be warranted for patients with terminal malignancy.


Asunto(s)
Neoplasias Abdominales/complicaciones , Bloqueo Nervioso Autónomo , Plexo Celíaco , Dolor Intratable/terapia , Anestésicos Locales/administración & dosificación , Bupivacaína/administración & dosificación , Etanol/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Dolor Intratable/diagnóstico , Dolor Intratable/etiología , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad
19.
Hong Kong Med J ; 8(3): 172-6, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12055361

RESUMEN

OBJECTIVES: To evaluate performance characteristics of the newly available handheld combined glucose and ketone meter for beta-hydroxybutyrate measurement. DESIGN: Laboratory method evaluation. MAIN OUTCOME MEASURES: Accuracy of beta-hydroxybutyrate measurement and effect of acetoacetate interference at clinically important beta-hydroxybutyrate levels. RESULTS: Deming regression analysis of beta-hydroxybutyrate measurements assessed by the ketone sensor and a laboratory enzymatic method revealed a coefficient of determination of 0.989 (P<0.001). Passing-Bablok regression analysis showed a linear relationship between the two methods, ie Y= -0.32+1.13X. The 95% confidence interval of the slope and y-intercept were: slope=1.13 (95% confidence interval, 1.04 to 1.22); intercept= -0.32 (95% confidence interval, -0.59 to -0.06). The Bland-Altman plot showed a small proportional bias between the two methods. The mean bias +/-2 standard deviations was between -0.53 and 0.67 mmol/L. Beta-hydroxybutyrate measurements made by the sensor were linear up to 6 mmol/L. Replicate analysis of two samples spiked with 3.6 mmol/L and 0.8 mmol/L of beta-hydroxybutyrate resulted in coefficients of variation of 3.3% and 13%, respectively. The presence of acetoacetate caused a negative interference in beta-hydroxybutyrate measurement. Beta-hydroxybutyrate recovery was 97.0% and 90.7% when the ketone body ratios were 6:1 and 3:1, respectively. CONCLUSION: The analytical performance of the sensor, when operated according to manufacturer's instructions, could meet the needs of point-of-care beta-hydroxybutyrate measurement. Additional clinical studies are needed to assess the benefits of introducing such an assay in a clinical setting.


Asunto(s)
Ácido 3-Hidroxibutírico/sangre , Autoanálisis/instrumentación , Técnicas Biosensibles/normas , Sistemas de Atención de Punto/normas , Periféricos de Computador , Cetoacidosis Diabética/diagnóstico , Humanos
20.
Br J Anaesth ; 88(4): 475-80, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12066721

RESUMEN

BACKGROUND: Previous studies have shown that 10-30% haemodilution with crystalloid may induce a hypercoagulable state demonstrable by using the Thrombelastograph (TEG). While most are in vitro studies, the few in vivo studies are limited by confounding surgical or 'environmental' factors. We conducted this randomized controlled study to evaluate the coagulation changes associated with in vivo haemodilution. METHODS: Twenty patients undergoing major hepatobiliary surgery were randomly allocated to one of two study groups. Group H (n = 10) had 30% blood volume withdrawn over 30 min and replaced with saline. Group C (n = 10) did not have any blood withdrawn. Blood samples were taken in both groups at 10, 20 and 30 min. Native TEG, complete blood count, coagulation profile, fibrinogen, antithrombin III, protein C and thrombin-antithrombin complex concentrations were measured. RESULTS: Compared with Group C, Group H patients had significantly greater shortening of r-time at 30 min (-30% vs +36%), greater shortening of k-time at all time points (-36% vs +17% at 10 min; -37% vs +44% at 20 min; -45% vs +49% at 30 min), and greater widening of alpha at 30 min (+71% vs +4%). The decrease in antithrombin III and other natural procoagulants and anticoagulants closely followed that of haematocrit, with the exception of thrombin-antithrombin complex. CONCLUSION: In vivo haemodilution of up to 30% with saline can induce a hypercoagulable state. The mechanism remains unclear as disproportionate dilution of natural anticoagulants was not detected. Thrombin-antithrombin complex concentration remained stable despite haemodilution in Group H, which may suggest increased thrombin generation.


Asunto(s)
Coagulación Sanguínea , Neoplasias del Sistema Digestivo/cirugía , Hemodilución , Cuidados Intraoperatorios , Adulto , Anciano , Antitrombina III/metabolismo , Femenino , Fibrinógeno/metabolismo , Hematócrito , Humanos , Masculino , Persona de Mediana Edad , Péptido Hidrolasas/metabolismo , Tromboelastografía
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