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INTRODUCTION: The routine use of pneumatic tourniquets in orthopaedic surgery is widely adopted in current practice; however, practice varies considerably based mainly on anecdotal and cultural traditions. This Quality Improvement Project evaluated current service as per the newly published British Orthopaedic Association Standards for Trauma & Orthopaedics guideline on 'The Safe Use of Intraoperative Tourniquets'. METHODS: Patient records were reviewed retrospectively for all patients who underwent orthopaedic surgery in September 2021 at one NHS hospital trust. Simultaneously, a nine-question survey was distributed to the orthopaedic teams allowing assessment of non-quantifiable aspects of the guidelines. The results were delivered as a local presentation, and trust-wide dissemination of posters using the mnemonic 'PRESSURE' was used to educate staff. The quantitative audit was repeated twice, after this intervention (March 2022) and after the advent of a new electronic patient record system with an online proforma (January 2023). RESULTS: There was significant improvement (p<0.05) in all aspects of tourniquet documentation between the audit cycles. Maximum advised tourniquet duration was exceeded in <2% of cases regardless of guideline publication. Recommended pressures were used in less than one-third of cases in all audit cycles, with no significant change throughout. More than 50% of respondents sized their tourniquet on 'whatever looked best fit'. CONCLUSIONS: Despite tourniquet usage being part of the UK Trauma & Orthopaedic Surgery curriculum, this study is the first to highlight a lack of compliance with 'gold standard' guidelines and the need for increased training for staff to ensure patients are exposed to the safest possible environment. Although electronic proformas can aid recording of information, the limitation to change is cultural tradition and anecdotal experience.
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BACKGROUND: Lateral end clavicle fractures can be challenging due to the small and often comminuted lateral fragment, problems with union and stability and implant morbidity. We retrospectively reviewed outcomes of Tightrope device in isolation to treat lateral end clavicle fractures. METHODS: Subjective and objective measures were assessed for 29 patients. The subjective comprised of functional clinical scores: Oxford shoulder score and EuroQoL5D. The objective measures were maintenance of fracture reduction, bone healing and complications. RESULTS: Median age was 36 years and 72% of cases were male patients. Average clinical follow up time was 21 months. Evaluation of latest radiographs showed that all reductions were maintained post-operatively. Twenty-two fractures had united and one patient had established non-union. Functional outcomes showed predominantly good results with Oxford shoulder score average of 41, EuroQoL5D index score of 0.78 and EuroQol Visual Analogue Scale 76. The overall post-operative complication rate was 10%; only one case requiring a secondary procedure. DISCUSSION: In our series, using the Tightrope as the sole device to treat displaced lateral end of clavicle fractures resulted in good radiological and functional outcomes, with minimal complications requiring secondary procedures. We believe the Tightrope device is a good method of fixing these challenging fractures and advocate its use.
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Hypertensive heart disease refers to changes in the myocardium that result from hypertension. The relationship between hypertensive heart disease and sudden cardiac death is well established, but there are few pathological studies. We examined the clinical and pathological features of hypertensive heart disease in sudden cardiac death victims from a national cardiovascular pathology registry. We investigated 5239 cases of sudden cardiac death between 1994 and 2018. Hearts were examined by two expert cardiac pathologists. Diagnostic criteria included history of hypertension, increased heart weight and left ventricular wall thickness in the absence of other causes. Collagen was quantified using picrosirius red staining and imaging software. Of 75 sudden cardiac death cases due to hypertensive heart disease (age at death: 54 ± 16 years; 56% males), 56 (75%) reported no prior cardiac symptoms. Thirty-four (45%) recorded a BMI ≥ 30. Only two (2.7%) had hypertensive heart disease diagnosed antemortem. Four (5%) were diagnosed clinically with hypertrophic cardiomyopathy, but lacked myocyte disarray at autopsy. All hearts showed concentric left ventricular hypertrophy and myocyte hypertrophy. Fibrosis was identified microscopically in 59 cases (81%). The posterior left ventricular wall showed the greatest increase in the percentage of collagen in hypertensive diseased hearts compared to controls (25.2% vs 17.9%, p = 0.034). Most sudden deaths due to hypertensive heart disease occur without prior cardiac symptoms; thus, clinical risk stratification is challenging. Hypertensive heart disease can be misdiagnosed in life as hypertrophic cardiomyopathy which has major implications for relatives. Pathologists require a history of hypertension and histology for a definitive diagnosis of hypertensive heart disease.
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Cardiomiopatía Hipertrófica , Cardiopatías , Hipertensión , Adulto , Anciano , Cardiomiopatía Hipertrófica/complicaciones , Cardiomiopatía Hipertrófica/patología , Colágeno , Muerte Súbita Cardíaca/epidemiología , Muerte Súbita Cardíaca/etiología , Femenino , Cardiopatías/complicaciones , Cardiopatías/patología , Humanos , Hipertensión/complicaciones , Hipertensión/patología , Masculino , Persona de Mediana Edad , MiocardioRESUMEN
PURPOSE: To investigate whether eyes with diabetic macular edema (DME) and central retinal thickness (CRT) >400 µm had better visual and anatomical outcomes compared to eyes with a CRT <400 µm when treated with intravitreal bevacizumab in a real-world setting. PATIENTS AND METHODS: Patients undergoing intravitreal bevacizumab therapy for DME were identified from the departmental database of a tertiary referral unit. Following the initial injection, a retreatment was performed for any persistent macular edema, unless there had been no previous response to repeated doses. Recorded parameters included visual acuity, CRT on optical coherence tomography (spectral domain optical coherence tomography [SD-OCT]), and SD-OCT characteristics. Comparisons were made between data at baseline and 12 months after the first injection, and differences were tested for statistical significance using the Student's t-test. RESULTS: In all, 175 eyes of 142 patients were analyzed. Patients in group 2 (CRT >400 µm) had significantly more injections than group 1 (CRT <400 µm) (4.0 versus 3.3; P=0.003). Both groups had similar numbers of eyes with preexisting epiretinal membrane and/or vitreomacular traction at baseline. The reduction in CRT was significantly greater in group 2 when compared to group 1 (P<0.0001). In terms of visual gain between baseline and month 12, each gained significantly by a mean of 0.12 logarithm of the minimum angle of resolution units (P=0.0001), but there was no difference between groups 1 and 2 (P=0.99). CONCLUSION: These results do not support a 400 µm baseline CRT cut-off for treating DME with bevacizumab, in contrast to published data on ranibizumab. Our results also indicate that patients with a thicker CRT require more bevacizumab injections, making treatment less cost-effective for these patients. Our results could be used by practitioners to support the use of bevacizumab in DME without applying a CRT cut-off.
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There is thought to be a link between vastus medialis oblique (VMO) architecture and patellofemoral pain syndrome (PFPS). Historical data are largely derived from older populations, whereas PFPS commonly affects younger populations. The aim of this study was to gather data on VMO architecture in young asymptomatic adults, to provide baseline values for comparison with symptomatic sufferers. VMO maximum fiber angle and insertion ratio were measured with ultrasound. The insertion ratio represents the proportion (%) of the patella which has the muscle fibers attaching to its medial border. Eighty knees from 40 healthy young subjects (18 males, 22 females, and age 20-30) were assessed. Individual Tegner scores were recorded to assess participants' level of physical activity. Results were compared with data in the literature for PFPS sufferers and normal older individuals. Mean fiber angle and insertion ratio were 56.6° and 57.8%, respectively. There was no significant difference between age groups. The insertion ratio was higher among females (61.2% F:53.6% M). There was some evidence of increased fiber angle and decreased insertion ratio with increased Tegner score. There was some overlap in fiber angle between healthy knees in this study and values reported elsewhere for pathological knees. VMO fiber angle and insertion ratio are not age-related. The overlap in fiber angle values between healthy and pathological knees suggests that the cause of PFPS is multifactorial. An individual's VMO architecture may be affected by their physical activity level, which could have important implications for PFPS.
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Articulación de la Rodilla/diagnóstico por imagen , Fibras Musculares Esqueléticas/diagnóstico por imagen , Rótula/diagnóstico por imagen , Músculo Cuádriceps/diagnóstico por imagen , Adulto , Femenino , Humanos , Articulación de la Rodilla/anatomía & histología , Masculino , Rótula/anatomía & histología , Síndrome de Dolor Patelofemoral/diagnóstico por imagen , Músculo Cuádriceps/anatomía & histología , Factores Sexuales , Ultrasonografía , Adulto JovenRESUMEN
AIM: To compare the 24-h intraocular pressure (IOP) control obtained with the bimatoprost-timolol fixed combination (BTFC) versus latanoprost in newly diagnosed, previously untreated exfoliation syndrome (XFS) or exfoliative glaucoma (XFG) patients with baseline morning IOP greater than 29 mm Hg. METHODS: One eye of 41 XFS/XFG patients who met inclusion criteria was included in this prospective, observer-masked, crossover, comparison protocol. All subjects underwent a 24-h untreated curve and were then randomised to either evening administered BTFC or latanoprost for 3 months and then switched to the opposite therapy. At the end of each treatment period, patients underwent a treated 24-h IOP assessment. RESULTS: 37 patients completed the trial. At baseline, mean untreated 24-h IOP was 31.1 mm Hg. Mean 24-h IOP with BTFC was significantly lower than with latanoprost (18.9 vs 21.2 mm Hg; p<0.001). Furthermore, BTFC reduced IOP significantly more than latanoprost at every time point, for the mean peak and trough 24-h IOP (p<0.001). There was no difference, however, in mean 24-h IOP fluctuation between the two medications (3.8 with BTFC vs 4.2 with latanoprost; p=0.161). Both treatments were well tolerated and there was no statistically significant difference for any adverse event between them. CONCLUSIONS: As first choice therapy in high-pressure, at-risk exfoliation patients, BTFC controlled mean 24-h IOP significantly better than latanoprost monotherapy.
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Amidas/uso terapéutico , Antihipertensivos/uso terapéutico , Ritmo Circadiano/efectos de los fármacos , Cloprostenol/análogos & derivados , Síndrome de Exfoliación/tratamiento farmacológico , Glaucoma/tratamiento farmacológico , Prostaglandinas F Sintéticas/uso terapéutico , Timolol/uso terapéutico , Anciano , Anciano de 80 o más Años , Amidas/efectos adversos , Antihipertensivos/efectos adversos , Bimatoprost , Cloprostenol/efectos adversos , Cloprostenol/uso terapéutico , Estudios Cruzados , Método Doble Ciego , Combinación de Medicamentos , Síndrome de Exfoliación/fisiopatología , Femenino , Glaucoma/fisiopatología , Humanos , Presión Intraocular/efectos de los fármacos , Latanoprost , Masculino , Persona de Mediana Edad , Hipertensión Ocular/tratamiento farmacológico , Hipertensión Ocular/fisiopatología , Estudios Prospectivos , Prostaglandinas F Sintéticas/efectos adversos , Timolol/efectos adversos , Tonometría Ocular , Resultado del Tratamiento , Pruebas del Campo Visual , Campos VisualesRESUMEN
PURPOSE: To compare retinal nerve fiber layer thickness (RNFLT) of normotensive eyes with exfoliation syndrome (XFS) and healthy eyes.â© METHODS: Sixty-four consecutive individuals with XFS and normal office-time intraocular pressure (IOP) and 72 consecutive healthy controls were prospectively enrolled for a cross-sectional analysis in this hospital-based observational study. The GDx-VCC parameters (temporal-superior-nasal-inferior-temporal [TSNIT] average, superior average, inferior average, TSNIT standard deviation (SD), and nerve fiber indicator [NFI]) were compared between groups. Correlation between various clinical parameters and RNFLT parameters was investigated with Spearman coefficient. â© RESULTS: The NFI, although within normal limits for both groups, was significantly greater in the XFS group compared to controls: the respective median and interquartile range (IQR) values were 25.1 (22.0-29.0) vs 15.0 (12.0-20.0), p<0.001. In the XFS group, all RNFLT values were significantly lower compared to controls (p<0.001). However, they were all within the normal clinical ranges for both groups: TSNIT average median (IQR): 52.8 (49.7-55.7) vs 56.0 (53.0-59.3) µm; superior average mean (SD): 62.3 (6.7) vs 68.8 (8.2) µm; inferior average mean (SD): 58.0 (7.2) vs 64.8 (7.7) µm, respectively. TSNIT SD was significantly lower in the XFS group, median (IQR): 18.1 (15.4-20.4) vs 21.0 (18.4-23.8), p<0.001. There was no systematic relationship between RNFLT and visual acuity, cup-to-disc ratio, IOP, central corneal thickness, Humphrey mean deviation, and pattern standard deviation in either group. â© CONCLUSIONS: Compared to control eyes, polarimetry-determined RNFLT was lower in XFS eyes with normal IOP. Therefore, close monitoring of RNFLT may facilitate early identification of those XFS eyes that convert to exfoliative glaucoma.
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Síndrome de Exfoliación/patología , Fibras Nerviosas/patología , Enfermedades de la Retina/patología , Polarimetría de Barrido por Laser , Anciano , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
BACKGROUND: Bacterial meningitis (BM) is a life-threatening disease, often related with serious complications and sequelae. Infants and children who survive bacterial meningitis often suffer neurological and other sequelae. METHODS: A total of 2,477 patients aged 1 month to 14 years old hospitalized in a Children's Hospital in Greece diagnosed with acute bacterial meningitis were collected through a Meningitis Registry, from 1974 to 2005. Clinical, laboratory and other parameters (sex, age, pathogen, duration of symptoms before and after admission) were evaluated through univariate and multivariate analysis with regard to sequelae. Analysis of acute complications were also studied but not included in the final model. RESULTS: The rate of acute complications (arthritis and/or subdural effusion) was estimated at 6.8% (152 out of 2,251 patients, 95%CI 5.8-7.9) while the rate of sequelae (severe hearing loss, ventriculitis, hydrocephalus or seizure disorder) among survivors was estimated at 3.3% (73 out of 2,207 patients, 95%CI 2.6-4.2). Risk factors on admission associated with sequelae included seizures, absence of hemorrhagic rash, low CSF glucose, high CSF protein and the etiology of meningitis. A combination of significant prognostic factors including presence of seizures, low CSF glucose, high CSF protein, positive blood culture and absence of petechiae on admission presented an absolute risk of sequelae of 41.7% (95%CI 15.2-72.3). CONCLUSIONS: A combination of prognostic factors of sequelae in childhood BM may be of value in selecting patients for more intensive therapy and in identifying possible candidates for new treatment strategies.
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Meningitis Bacterianas/complicaciones , Meningitis Bacterianas/patología , Enfermedades del Sistema Nervioso/diagnóstico , Adolescente , Niño , Preescolar , Femenino , Grecia , Humanos , Lactante , Masculino , Pronóstico , Sistema de RegistrosAsunto(s)
Pueblo Asiatico , Capilares/fisiopatología , Enfermedades Cardiovasculares/fisiopatología , Piel/irrigación sanguínea , Población Blanca , Adulto , Enfermedades Cardiovasculares/etnología , Estudios de Cohortes , Femenino , Dedos/irrigación sanguínea , Humanos , Masculino , Factores de Riesgo , Adulto JovenRESUMEN
BACKGROUND: Childhood meningitis continues to be an important cause of mortality in many countries. The search for rapid diagnosis of acute bacterial meningitis has lead to the further exploration of prognostic factors. This study was scheduled in an attempt to analyze various clinical symptoms as well as rapid laboratory results and provide an algorithm for the prediction of specific bacterial aetiology of childhood bacterial meningitis. METHODOLOGY AND PRINCIPAL FINDINGS: During the 32 year period, 2477 cases of probable bacterial meningitis (BM) were collected from the Meningitis Registry (MR). Analysis was performed on a total of 1331 confirmed bacterial meningitis cases of patients aged 1 month to 14 years. Data was analysed using EPI INFO (version 3.4.3-CDC-Atlanta) and SPSS (version 15.0-Chicago) software. Statistically significant (p<0.05) variables were included in a conditional backward logistic regression model. A total of 838 (63.0%) attributed to Neisseria meningitidis, 252 (18.9%) to Haemophilus influenzae, 186 (14.0%) to Streptococcus pneumoniae and 55 (4.1%) due to other bacteria. For the diagnosis of Meningococcal Meningitis, the most significant group of diagnostic criteria identified included haemorrhagic rash (OR 22.36), absence of seizures (OR 2.51), headache (OR 1.83) and negative gram stain result (OR 1.55) with a Positive Predictive Value (PPV) of 96.4% (95%CI 87.7-99.6). For the diagnosis of Streptococcus pneumoniae, the most significant group of diagnostic criteria identified included absence of haemorrhagic rash (OR 13.62), positive gram stain (OR 2.10), coma (OR 3.11), seizures (OR 3.81) and peripheral WBC > or = 15000/microL (OR 2.19) with a PPV of 77.8% (95%CI 40.0-97.2). For the diagnosis of Haemophilus influenzae, the most significant group of diagnostic criteria included, absence of haemorrhagic rash (OR 13.61), age > or = 1 year (OR 2.04), absence of headache (OR 3.01), CSF Glu < 40 mg/dL (OR 3.62) and peripheral WBC < 15,000/microL (OR 1.74) with a PPV of 58.5% (95%CI 42.1-73.7). CONCLUSIONS: The use of clinical and laboratory predictors for the assessment of the causative bacterial pathogen rather than just for predicting outcome of mortality seems to be a useful tool in the clinical management and specific treatment of BM. These findings should be further explored and studied.
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Meningitis Bacterianas/diagnóstico , Sistema de Registros , Adolescente , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Meningitis Bacterianas/epidemiología , Meningitis Bacterianas/microbiología , Especificidad de la EspecieRESUMEN
Cannabis is generally considered a drug of low toxicity. Although attention has focused on its neuropsychiatric effects, little has been given to cardiovascular side effects. Here we report a case of atrial tachyarrhythmias following cannabis use, and review the literature on its cardiovascular effects and complications.
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Fumar Marihuana/efectos adversos , Taquicardia/etiología , Adulto , Femenino , Humanos , Taquicardia/terapiaRESUMEN
Wasp stings have been associated with a wide variety of local and systemic reactions including, rarely, tachyarrhythmias. We discuss a case of atrial flutter occurring in a 64-year-old man following a single sting in the absence of anaphylaxis. The pathogenesis is discussed and the literature reviewed.
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Aleteo Atrial/etiología , Mordeduras y Picaduras de Insectos/complicaciones , Avispas , Animales , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Rarefaction of skin capillaries in people with intermittent borderline essential hypertension suggests a primary or an early abnormality that may antedate the onset of sustained hypertension. OBJECTIVE: To compare skin capillary density in subjects with and without a family history of essential hypertension. SUBJECTS: 21 normotensive individuals, one or both of whose parents had essential hypertension (mean age 39.3 years; blood pressure 124/79 mm Hg); 21 normotensive controls with no family history of hypertension (age 46.3 years; blood pressure 124/78 mm Hg). METHODS: The skin of the dorsum of the fingers was examined by intravital capillary microscopy before and after venous congestion at 60 mm Hg for two minutes. RESULTS: By analysis of variance, both baseline and maximum skin capillary density were lower in subjects with a family history of essential hypertension than in those with no family history (baseline: 67 v 79 capillaries per field, p = 0.008; maximum: 74 v 93 capillaries per field, p < 0.0005). CONCLUSIONS: Capillary rarefaction in essential hypertension may occur before the increase in blood pressure and could, at least in part, reflect a primary rather than a secondary abnormality.
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Capilares , Familia , Hipertensión/patología , Piel/irrigación sanguínea , Adulto , Humanos , Hipertensión/genética , LinajeRESUMEN
Hydroxyapatite (HAp) was prepared using a microemulsion route in combination with the pH-shock wave method. The samples as received consisted of amorphous aggregated particles, which had remarkable mesoporosity with a narrow pore size distribution. After being heated at 650 degrees C, the A-type carbonate hydroxyapatite was crystallized at 635 degrees C in particles of similar size (40--120 nm) with no internal porosity. At a higher temperature (900 degrees C) a sintering process took place, resulting in network of a larger particles, consisting of HAp and beta-tricalcium phosphate (beta-TCP). The crystallization of HAp occurs at 635 degrees C with an activation energy of 62.7--72.2 kcalmol(-1).
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Durapatita/síntesis química , Nanoestructuras/química , Cristalización , Emulsiones/química , Concentración de Iones de Hidrógeno , Porosidad , TemperaturaRESUMEN
AIMS: Patients with arterial hypertension often have a reduction in capillary density (rarefaction) and a reduction in coronary flow reserve because of functional and structural alterations of the coronary microcirculation. Patients with chest pain and normal coronary arteriograms may have coronary microvascular dysfunction, but it is not known whether capillary rarefaction plays a role in the pathogenesis of this syndrome. The aim of this study was to compare capillary density in hypertensive and normotensive subjects with anginal chest pain and normal coronary arteriograms vs asymptomatic hypertensives and healthy controls. METHODS AND RESULTS: We studied 49 patients with typical anginal chest pain, positive exercise testing and normal coronary arteriograms; 22 were hypertensive and 27 were normotensive. We used intra-vital video-microscopy to examine the skin of the dorsum of the middle finger of the non-dominant hand before and after maximization of perfused capillaries with venous congestion. Mean capillary density was significantly lower in patients with chest pain and normal coronary arteriograms independent of their blood pressure level, compared to normotensive healthy controls. Differences were found both at baseline [51+/-2 (hypertensive) and 52+/-2 (normotensive) vs 65+/-2 (controls) per 0.56 mm(2) respectively], (P<0.0001) and after maximization [57+/-3 (hypertensive) and 59+/-2 (normotensive) versus 75+/-3 (controls) respectively] (P<0.0001). CONCLUSIONS: Skin capillary density is significantly lower in patients with chest pain and normal coronary arteriograms compared to normotensive controls. The pathophysiological importance of capillary rarefaction in patients with chest pain and normal coronary arteriograms remains unknown. Further studies are needed to determine whether the abnormality is associated with myocardial flow disturbances such that the findings can be extended to the heart.
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Capilares/patología , Hipertensión/fisiopatología , Angina Microvascular/fisiopatología , Piel/irrigación sanguínea , Capilares/fisiopatología , Estudios de Casos y Controles , Angiografía Coronaria , Femenino , Humanos , Masculino , Angioscopía Microscópica , Persona de Mediana EdadRESUMEN
This multicenter study evaluated the efficacy of candesartan cilexetil, an angiotensin II type 1 receptor antagonist, used alone or in combination with amlodipine or in combination with amlodipine and hydrochlorothiazide in the treatment of patients with moderate-to-severe essential hypertension. After a 2-week, single-blind, placebo run-in period, patients entered a 12-week, open-label, dose-titration period. The candesartan cilexetil dose was increased from 8 to 16 mg once daily; amlodipine (5 mg once daily), hydrochlorothiazide (25 mg once daily), and additional medication were also added sequentially if necessary. Patients then entered a final 4-week, parallel-group, double-blind, randomized, placebo-controlled withdrawal period of candesartan alone. A total of 216 patients were recruited. After a 2-week run-in period on placebo tablets, mean sitting blood pressure (BP) was 175/108 mm Hg. At the end of the 12-week dose-titration/maintenance period, mean sitting BP fell to 141/88 mm Hg. In 67 patients who were randomized to placebo and had their candesartan withdrawn, there was a highly significant increase in mean systolic/diastolic BP (13/6 mm Hg) compared with those patients who continued with candesartan (ANCOVA, P:<0.0001). In conclusion, candesartan cilexetil is an effective BP-lowering drug when used alone or in combination with amlodipine or amlodipine plus hydrochlorothiazide in the treatment of moderate-to-severe essential hypertension. The drug was well tolerated throughout the investigation period.
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Amlodipino/uso terapéutico , Antihipertensivos/uso terapéutico , Bencimidazoles/uso terapéutico , Compuestos de Bifenilo/uso terapéutico , Hidroclorotiazida/uso terapéutico , Hipertensión/tratamiento farmacológico , Tetrazoles , Aldosterona/sangre , Análisis de Varianza , Monitoreo Ambulatorio de la Presión Arterial , Método Doble Ciego , Quimioterapia Combinada , Femenino , Humanos , Hipertensión/sangre , Israel , Masculino , Persona de Mediana Edad , Renina/sangre , Método Simple Ciego , Reino UnidoRESUMEN
We recently showed that rarefaction of skin capillaries in the dorsum of the fingers of patients with essential hypertension is due to the structural (anatomic) absence of capillaries rather than functional nonperfusion. It is not known whether this rarefaction is primary (ie, antedates the onset of hypertension) or secondary (ie, as a consequence of sustained and prolonged elevation of blood pressure [BP]). The aim of the present investigation was to study skin capillary density in a group of patients with mild borderline hypertension to assess whether rarefaction antedates the onset of sustained elevation of BP. The study group included 18 patients with mild borderline hypertension (mean supine BP, 136/83 mm Hg), 32 normotensive controls (mean BP, 126/77 mm Hg), and 45 patients with established essential hypertension (mean BP, 156/98 mm Hg). The skin of the dorsum of the fingers was examined by intravital capillary videomicroscopy before and after venous congestion at 60 mm Hg for 2 minutes. Patients with borderline essential hypertension had the lowest resting capillary density when compared with normotensive controls and patients with established hypertension. Maximal capillary density with venous congestion in the borderline group remained the lowest. The study confirmed that patients with borderline essential hypertension have skin capillary densities that are equally low as or even lower than patients with established hypertension. Both groups had significantly lower capillary densities than normal controls. One explanation for the results is that capillary rarefaction may be due to an early structural abnormality in essential hypertension.
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Dedos/irrigación sanguínea , Hipertensión/patología , Análisis de Varianza , Presión Sanguínea , Capilares/patología , Estudios de Casos y Controles , Femenino , Humanos , Hipertensión/fisiopatología , Masculino , Microscopía por Video , Persona de Mediana EdadRESUMEN
Intravital capillary video-microscopy is a dynamic method for studying skin capillaries. The technique of direct intravital microscopy (without dyes) depends on the presence of red blood cells inside capillaries for their identification. The aim of the present study was to compare different techniques to try to establish the best method for maximizing the number of visible perfused capillaries during intravital capillary microscopy. We compared the effects of venous congestion with those of post-occlusive reactive hyperaemia (Study 1). We also investigated venous congestion followed first by post-occlusive reactive hyperaemia and then by a core heat load test (Study 2). Finally we investigated venous congestion followed by post-occlusive reactive hyperaemia combined with venous congestion (Study 3). In Study 1, capillary density increased with venous congestion from a baseline value of 74+/-2 (mean+/-S.E.M.) per field to 82+/-3 per field (P<0.0001; analysis of variance). With reactive hyperaemia, there was an apparent decrease in visible capillary density to 69+/-2 per field. In Study 2, baseline capillary density was 69+/-4 per field, and this increased significantly with venous congestion to 74+/-4 per field (P=0.01). With both reactive hyperaemia and core heat load, the apparent density was 62+/-4 per field. In Study 3 the baseline density was 70+/-2 per field, and this increased significantly with venous congestion to 80+/-3 per field (P<0.0001). With reactive hyperaemia combined with venous congestion, the density was 81+/-3 per field (P=0.328 compared with venous congestion alone). The results show that venous congestion at 60 mmHg for 2 min is the most effective method for visualization of the maximal number of perfused skin capillaries during intravital video-microscopy.