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1.
Crit Care Resusc ; 22(1): 53-62, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32102643

RESUMO

OBJECTIVE: Postprandial hypotension occurs frequently in older survivors of critical illness at 3 months after discharge. We aimed to determine whether postprandial hypotension and its predictors - gastric dysmotility and cardiovascular autonomic dysfunction - persist or resolve as older survivors of critical illness recover, and whether postprandial hypotension after intensive care unit (ICU) discharge is associated with adverse outcomes at 12 months. DESIGN: Prospective observational study. SETTING: Tertiary medical-surgical ICU. PARTICIPANTS: Older adults (aged ≥ 65 years) who had been studied 3 months after ICU discharge and who returned for a follow-up study at 12 months after discharge. MAIN OUTCOME MEASURES: On both occasions after fasting overnight, participants consumed a 300 mL drink containing 75 g glucose, radiolabelled with 20 MBq 99mTcphytate. Blood pressure, heart rate, blood glucose concentration and gastric emptying rate were measured concurrently before and after ingestion of the drink. Falls, quality of life, hospitalisation and mortality rates were also quantified. RESULTS: Out of 35 older adults studied at 3 months, 22 returned for the follow-up study at 12 months. Postprandial hypotension was evident in 29% of participants (95% CI, 14-44%) at 3 months and 10% of participants (95% CI, 1-30%) at 12 months. Postprandial hypotension at 3 months was associated with a more than threefold increase in the risk of falls in the year after ICU discharge (relative risk, 3.7 [95% CI, 1.6-8.8]; P = 0.003). At 12 months, gastric emptying was normal (mean time taken for 50% of gastric contents to empty, 101.6 [SD, 33.3] min) and cardiovascular autonomic dysfunction prevalence was low (9% [95% CI, 1-29%]). CONCLUSIONS: In older adults who were evaluated 3 and 12 months after ICU discharge, postprandial hypotension at 3 months was associated with an increased risk of subsequent falls, but the prevalence of postprandial hypotension decreased with time.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Sistema Nervoso Autônomo/fisiologia , Estado Terminal , Hipotensão/complicações , Hipotensão/etiologia , Período Pós-Prandial , Idoso , Pressão Sanguínea , Feminino , Seguimentos , Humanos , Hipotensão/epidemiologia , Hipotensão/fisiopatologia , Masculino , Estudos Prospectivos , Qualidade de Vida
2.
Adv Exp Med Biol ; 1232: 69-75, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893396

RESUMO

We investigated the relationship between cerebral oxygenation (COX) and skin blood flow (SkBF) at the left frontal lobes of 10 healthy young men during progressive hypoxia (∼ -1 h at each of 21%, 18%, 15%, and 12% of inspired oxygen [FiO2]). Acute hypotension was manipulated by a thigh-cuff-release technique, where a pressure of 220 mmHg was applied at both thigh muscles for 3 min and the cuff was immediately released to induce acute hypotension. While the resting baseline for COX before the thigh-cuff release manipulation decreased gradually with the reduction of FiO2 (P < 0.05), the resting baseline for SkBF, mean arterial blood pressure (MAP), and cutaneous vascular conductance (CVC) were unaffected by FiO2 (P > 0.05). The acute hypotension that was induced by the thigh-cuff release decreased COX, SkBF, MAP, and CVC; thereafter, these values recovered toward their baseline values. During the hypotension phase, while the time to the nadir values for COX slowed progressively with reductions in FiO2 (P < 0.05), those for SkBF, MAP, and CVC were unaffected by FiO2 (P > 0.05). These results suggest that COX may not be associated with SkBF for the protocol or with the subjects in the present study.


Assuntos
Circulação Cerebrovascular , Lobo Frontal , Hipotensão , Pele , Adulto , Velocidade do Fluxo Sanguíneo , Lobo Frontal/fisiologia , Hemodinâmica , Humanos , Hipotensão/fisiopatologia , Masculino , Pele/irrigação sanguínea , Adulto Jovem
3.
Acta Cir Bras ; 34(11): e201901107, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31939503

RESUMO

PURPOSE: To establish a hypotensive brain death pig model and observe the effects of hypotension on small bowel donors. METHODS: The hypotensive brain death model was produced using the modified intracranial water sac inflation method in ten domestic crossbred pigs. Effects of hypotensive brain death on small bowel tissue morphology were evaluated through changes in intestinal tissue pathology, tight junction protein of the intestinal mucosa and plasma intestinal fatty acid-binding protein (i-FABP) levels. The pathophysiological mechanism was examined based on changes in superior mesenteric artery (SMA) blood flow and systemic hemodynamics. RESULTS: After model establishment, SMA blood flow, and the mean arterial pressure (MAP) significantly decreased, while heart rate increased rapidly and fluctuated significantly. Small bowel tissue morphology and levels of tight junction protein of the intestinal mucosa showed that after model establishment, small bowel tissue injury was gradually aggravated over time (P<0.05). Plasma i-FABP levels significantly increased after brain death (P<0.05). CONCLUSIONS: A hypotensive brain death pig model was successfully established using an improved intracranial water sac inflation method. This method offers a possibility of describing the injury mechanisms more clearly during and after brain death.


Assuntos
Morte Encefálica/fisiopatologia , Modelos Animais de Doenças , Hipotensão/fisiopatologia , Intestino Delgado/patologia , Intestino Delgado/transplante , Animais , Biópsia , Western Blotting , Ensaio de Imunoadsorção Enzimática , Proteínas de Ligação a Ácido Graxo/sangue , Feminino , Hemodinâmica , Intestino Delgado/irrigação sanguínea , Masculino , Microscopia Eletrônica de Transmissão , Reprodutibilidade dos Testes , Suínos , Fatores de Tempo , Proteína da Zônula de Oclusão-1/análise
5.
J Shoulder Elbow Surg ; 29(1): 79-85, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31405715

RESUMO

BACKGROUND: The beach chair position is commonly used when performing shoulder arthroplasty. However, this position has been associated with hypotension, potentially leading to cerebral hypoperfusion, which may cause neurologic injury. In addition, shoulder arthroplasty cases are associated with longer operative times, posing a potentially greater risk of cerebral hypoperfusion. We aim to evaluate the risk of cerebral desaturation events (CDEs) during the course of total shoulder arthroplasty. METHODS: Twenty-six patients undergoing shoulder arthroplasties were monitored for changes in cerebral perfusion. Seven specific time-points during the procedure were labeled for comparison of events: baseline, beach chair, incision, humeral broaching, glenoid reaming, glenoid component implantation, and humeral component implantation. Cerebral oxygen perfusion was measured using near-infrared spectroscopy. A CDE was described as a decrease of oxygen saturation greater than 20%. RESULTS: Nineteeen of 25 subjects experienced a CDE. 42% of these patients experienced CDEs during semi-beach chair positioning. Patients experienced the largest oxygen saturation drop during semi-beach chair positioning. Transition from baseline to semi-beach chair was the only event to have a statistically significant decrease in cerebral perfusion (8%, P < .05). There was a statistically significant percentage change in mean oxygen saturation in the semi-beach chair interval (10%, P < .01) and the semi-beach chair to incision interval (7%, P < .01). CONCLUSIONS: Most patients experienced an intraoperative CDE, with greatest incidence during semi-beach chair positioning. The largest decline in cerebral oxygen saturation occurred during semi-beach chair positioning. Implant implantation was not associated with decrease in cerebral oximetry.


Assuntos
Artroplastia do Ombro , Cérebro/metabolismo , Oxigênio/metabolismo , Posicionamento do Paciente , Idoso , Circulação Cerebrovascular , Feminino , Humanos , Hipotensão/etiologia , Hipotensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Oximetria , Posicionamento do Paciente/efeitos adversos , Estudos Prospectivos , Espectroscopia de Luz Próxima ao Infravermelho
6.
Best Pract Res Clin Anaesthesiol ; 33(2): 189-197, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31582098

RESUMO

Blood pressure is the main determinant of organ perfusion. Hypotension is common in patients having surgery and in critically ill patients. The severity and duration of hypotension are associated with hypoperfusion and organ dysfunction. Hypotension is mostly treated reactively after low blood pressure values have already occurred. However, prediction of hypotension before it becomes clinically apparent would allow the clinician to treat hypotension pre-emptively, thereby reducing the severity and duration of hypotension. Hypotension can now be predicted minutes before it actually occurs from the blood pressure waveform using machine-learning algorithms that can be trained to detect subtle changes in cardiovascular dynamics preceding clinically apparent hypotension. However, analyzing the complex cardiovascular system is a challenge because cardiovascular physiology is highly interdependent, works within complicated networks, and is influenced by compensatory mechanisms. Improved hemodynamic data collection and integration will be a key to improve current models and develop new hypotension prediction models.


Assuntos
Determinação da Pressão Arterial/métodos , Cuidados Críticos/métodos , Hipotensão/diagnóstico , Hipotensão/fisiopatologia , Assistência Perioperatória/métodos , Determinação da Pressão Arterial/tendências , Cuidados Críticos/tendências , Humanos , Aprendizado de Máquina/tendências , Assistência Perioperatória/tendências , Valor Preditivo dos Testes
7.
Cell Mol Biol (Noisy-le-grand) ; 65(6): 28-32, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31472056

RESUMO

Heparin and protamine are two indispensable agents of cardiopulmonary bypass surgery with effects on the cardiovascular and hematological system. Heparin is used as an anticoagulant in open heart surgery; whereas protamine is used to neutralize heparin effects when surgery is terminated. Protamine is given in order to neutralize heparin effects after cardiopulmonary bypass surgery and it causes hypotension in patients. However, the mechanism of this side effect is not clearly known. Current mechanism is that hypotension occurs after the administration of protamine due to the conformational change in the calcium channels or anaphylactoid thromboxane release or serum ionized calcium levels. The present study was to explain how protamine causes hypotension in evidence-based medicine indexed in PubMed and Web of Science. In addition to above  mechanisms, possibly  the infused protamine binds heparin and causes the coagulation cascade to activate heparin-AT complex on thrombin beside activating FXIa, FXa and FIXa and causing the re-use of Ca2+. The re-use of Ca2+ at the coagulation cascade initiates an anion gap and it is assumed that hypotension develops because of the Ca2+ deficiency. Ca2+ ions are trapped in the thrombus by the resumption of thrombus formation. Ca2+ ions trapped in the thrombus cannot be used, so that Ca2+ ion deficit will develop in circulation and hypotension occurs due to the insufficiency of Ca2+ ions. The administration of Ca2+ ions together with the protamine might help to eliminate the side effect of the protamine (hypotension) while neutralizing heparin after open heart surgery in light of the information provided in the literature.


Assuntos
Cálcio/metabolismo , Ponte Cardiopulmonar , Hipotensão/metabolismo , Protaminas/metabolismo , Pressão Sanguínea , Homeostase , Humanos , Hipotensão/fisiopatologia , Trombose/patologia
8.
Postgrad Med ; 131(7): 415-422, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31424301

RESUMO

Alzheimer's disease (AD) is the most common form of dementia manifesting as alterations in cognitive abilities, behavior, and deterioration in memory which is progressive, leading to gradual worsening of symptoms. Major pathological features of AD are accumulations of neuronal amyloid plaques and neurofibrillary tangles, with early lesions appearing primarily in the hippocampus, the area of the brain involved in memory and learning. Cardiovascular-related risk factors are believed to play a crucial role in disease development and the acceleration of cognitive deterioration by worsening cerebral perfusion, promoting disturbances in amyloid clearance. Current evidence supports hypertension, hypotension, heart failure, stroke and coronary artery diseases as potential factors playing a role in cognitive decline in patients with Alzheimer's dementia. Although dementia due to cardiovascular deficits is more strongly linked to the development of vascular dementia, a stepwise decline in cognition, recent researches have also discovered its deleterious influence on AD development.


Assuntos
Doença de Alzheimer/fisiopatologia , Doenças Cardiovasculares/fisiopatologia , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Doenças Cardiovasculares/epidemiologia , Circulação Cerebrovascular , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/fisiopatologia , Progressão da Doença , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Hipotensão/epidemiologia , Hipotensão/fisiopatologia , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/fisiopatologia
9.
Hypertension ; 74(3): 645-651, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31327266

RESUMO

Alpha-blockers (ABs) are commonly prescribed as part of a multidrug regimen in the management of hypertension. We set out to assess the risk of hypotension and related adverse events with AB use compared with other blood pressure (BP) lowering drugs using a population-based, retrospective cohort study of women (≥66 years) between 1995 and 2015 in Ontario, Canada. Cox proportional hazards examined the association of AB use and hypotension and related events (syncope, fall, and fracture) compared with other BP lowering drugs matched via a high dimensional propensity score. The primary outcome was a composite of hospitalizations for hypotension and related events (syncope, fractures, and falls) within 1 year. From 734 907 eligible women, 14 106 were dispensed an AB (mean age, 75.7; standard deviation 6.9 years, median follow-up 1 year) and matched to 14 106 dispensed other BP lowering agents. The crude incidence rate of hypotension and related events was 95.7 (95% CI [confidence interval], 90.4-101.1, events 1214 [8.6%]) with AB and 79.8 (95% CI, 74.9-84.7 per 1000 person-years, events 1025 [7.3%]) with other BP lowering medications (incident rate ratio, 1.20; 95% CI, 1.10-1.30). The risk was higher for hypotension (hazard ratio, 1.71; 95% CI, 1.33-2.20) and syncope (hazard ratio, 1.44; 95% CI, 1.18-1.75) with no difference in falls, fractures, adverse cardiac events, or all-cause mortality. Treatment of hypertension in women with ABs is associated with a higher risk of hypotension and hypotension-related events compared with other BP lowering agents. Our findings suggest that ABs should be used with caution, even as add on therapy for hypertension.


Assuntos
Antagonistas Adrenérgicos alfa/efeitos adversos , Hipertensão/tratamento farmacológico , Hipotensão/induzido quimicamente , Hipotensão/epidemiologia , Acidentes por Quedas/estatística & dados numéricos , Antagonistas Adrenérgicos alfa/uso terapêutico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Canadá , Estudos de Coortes , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Fraturas Ósseas/diagnóstico , Fraturas Ósseas/epidemiologia , Avaliação Geriátrica/métodos , Humanos , Hipertensão/diagnóstico , Hipotensão/fisiopatologia , Incidência , Prognóstico , Pontuação de Propensão , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Síncope/diagnóstico , Síncope/epidemiologia , Resultado do Tratamento
10.
Geriatr Gerontol Int ; 19(9): 874-878, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31359614

RESUMO

AIM: The aim of the present study was to evaluate the incidence, risk factors, clinical characteristics and outcomes of acute kidney injury (AKI) in octogenarians admitted to the emergency room, and to compare these parameters with those in a younger group of patients admitted in the same period. METHODS: This is a prospective, observational, single-center study that enrolled adult patients admitted to the emergency room of Shaare Zedek Medical Center, Jerusalem, Israel. Patients were stratified by age (≥80 years or <80 years) and followed up prospectively until discharge. The incidence of AKI, in-hospital mortality and duration of hospital stay were recorded. RESULTS: Of 319 patients, 128 were octogenarians (mean age 86.7 years, range 80-105 years) and 191 were younger (mean age 60.6 years, range 18-79 years). The incidence of AKI and in-hospital mortality was significantly higher in octogenarians (16.4% vs 12.6%, P = 0.039 and 15.6% vs 3.1%, P = 0.001, respectively). In multivariate analysis, only low systolic blood pressure at admission in octogenarians (P = 0.002), and a history of chronic kidney disease (P < 0.001) and hypoalbuminemia (P = 0.001) in the younger patients were independent risk factors for AKI. CONCLUSION: The present results confirm the observation that AKI is common in octogenarians. We identified systolic blood pressure as the only independent variable associated with AKI in octogenarians. However, the role of therapeutic strategies aimed to increase systolic blood pressure and diminish complications in octogenarians remains to be elucidated. Geriatr Gerontol Int 2019; 19: 874-878.


Assuntos
Lesão Renal Aguda , Emergências/epidemiologia , Hipotensão , Lesão Renal Aguda/diagnóstico , Lesão Renal Aguda/mortalidade , Fatores Etários , Idoso de 80 Anos ou mais , Feminino , Mortalidade Hospitalar , Humanos , Hipotensão/diagnóstico , Hipotensão/epidemiologia , Hipotensão/fisiopatologia , Incidência , Israel/epidemiologia , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Medição de Risco , Fatores de Risco
11.
Am J Health Syst Pharm ; 76(2): 101-107, 2019 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31361800

RESUMO

OBJECTIVE: Clinical data and gaps in knowledge regarding angiotensin II (AT2), which was approved by the Food and Drug Administration in December 2017 via priority review for treatment of septic and other vasodilatory shock, is discussed. SUMMARY: AT2 is an endogenous peptide that raises blood pressure via vasoconstriction and increased aldosterone release. It was previously available but withdrawn from the US market; previous low-quality research describes increases in mean arterial pressure (MAP). The recent approval of AT2 was based on data from a Phase III randomized trial comparing i.v. AT2 (n = 163) with placebo use (n = 158) in patients with vasodilatory shock receiving high doses of other vasopressors. AT2 significantly increased achievement of the primary endpoint, MAP response at 3 hours after the start of infusion, relative to placebo use (69.9% [n = 114] versus 23.4% [n = 37], p < 0.0001). Serious adverse events occurred in 60.7% (n = 99) and 67.1% (n = 106) of patients treated with AT2 and placebo recipients, respectively, including venous and arterial thromboembolic events (12.9% [n = 21] and 5.1% [n = 8], respectively). No significant effects of AT2 on 7- or 28-day mortality were seen among all patients in the ATHOS-3 trial. However, post hoc analyses suggested that AT2 may reduce mortality in patients with low baseline AT2 levels, exaggerated response to AT2, and acute kidney injury receiving concomitant renal replacement therapy. Overall, due to shortcomings of the ATHOS-3 trial data and the absence of confirmatory studies, the optimal place in therapy of AT2 for vasodilatory shock cannot be determined with confidence. CONCLUSION: Intravenous AT2 represents a novel treatment strategy for refractory septic or other vasodilatory shock, although findings of safety and efficacy have not been replicated and the drug's optimal place in therapy is uncertain.


Assuntos
Angiotensina II/administração & dosagem , Hipotensão/tratamento farmacológico , Choque Séptico/tratamento farmacológico , Vasoconstritores/administração & dosagem , Administração Intravenosa , Angiotensina II/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Humanos , Hipotensão/mortalidade , Hipotensão/fisiopatologia , Fluxo Sanguíneo Regional/efeitos dos fármacos , Fluxo Sanguíneo Regional/fisiologia , Choque Séptico/mortalidade , Choque Séptico/fisiopatologia , Resultado do Tratamento , Vasoconstritores/efeitos adversos
12.
Nutrients ; 11(8)2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31349678

RESUMO

Postprandial hypotension (PPH) is under-recognised, but common, particularly in the elderly, and is of clear clinical importance due to both the independent association between PPH and an increase in mortality and lack of effective management for this condition. Following health concerns surrounding excessive consumption of sugar, there has been a trend in the use of low- or non-nutritive sweeteners as an alternative. Due to the lack of literature in this area, we conducted a systematic search to identify studies relevant to the effects of different types of sweeteners on postprandial blood pressure (BP). The BP response to ingestion of sweeteners is generally unaffected in healthy young subjects, however in elderly subjects, glucose induces the greatest decrease in postprandial BP, while the response to sucrose is less pronounced. The limited studies investigating other nutritive and non-nutritive sweeteners have demonstrated minimal or no effect on postprandial BP. Dietary modification by replacing high nutritive sweeteners (glucose, fructose, and sucrose) with low nutritive (d-xylose, xylitol, erythritol, maltose, maltodextrin, and tagatose) and non-nutritive sweeteners may be a simple and effective management strategy for PPH.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Hipotensão/induzido quimicamente , Adoçantes não Calóricos/efeitos adversos , Adoçantes Calóricos/efeitos adversos , Período Pós-Prandial , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipotensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
13.
J Stroke Cerebrovasc Dis ; 28(8): 2155-2158, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31103551

RESUMO

OBJECTIVE: To determine adherence to nimodipine administration in patients admitted with aneurysmal subarachnoid hemorrhage (aSAH). BACKGROUND: Oral nimodipine (60 mg every 4 hours for 21 days) is recommended by the national guidelines for aSAH. A Cochrane systematic review has determined that nimodipine reduces the risk of cerebral ischemia and is currently the only effective drug for the prevention of vasospasm in aSAH patients. DESIGN/METHODS: We retrospectively analyzed 109 patients with aSAH admitted to the Neurosciences Intensive Care Unit (NICU) at a tertiary care medical center between 2010 and 2013. Nimodipine-prescribing patterns, days of therapy completed, and adverse effects were tabulated. Patients not initiated on nimodipine and reasons for prematurely stopping therapy were noted. RESULTS: One hundred two (93%) patients with aSAH were started on oral nimodipine upon admission to the NICU. Early death (3%) and hypotension (1%) were reasons why patients were not started on nimodipine. Only 36 (33%) patients received nimodipine, 60 mg orally every 4 hours for 21 days. In 26 patients (39%), the dose of nimodipine was reduced because of excessive drops in blood pressure. Transient discontinuation occurred in 2 (2%) patients. Thirty one (47%) patients were discharged from the hospital before 21 days and nimodipine was not ordered to continue at home. CONCLUSION: We found that the majority of patients with aSAH in our practice did not complete 21 days of nimodipine. Hypotension was mostly responsible for dosing change or discontinuation.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/administração & dosagem , Nimodipina/administração & dosagem , Padrões de Prática Médica , Hemorragia Subaracnóidea/tratamento farmacológico , Vasodilatadores/administração & dosagem , Administração Oral , Adulto , Idoso , Bloqueadores dos Canais de Cálcio/efeitos adversos , Esquema de Medicação , Feminino , Fidelidade a Diretrizes , Humanos , Hipotensão/induzido quimicamente , Hipotensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Nimodipina/efeitos adversos , Guias de Prática Clínica como Assunto , Padrões de Prática Médica/normas , Padrões de Prática Médica/tendências , Estudos Retrospectivos , Fatores de Risco , Hemorragia Subaracnóidea/diagnóstico , Hemorragia Subaracnóidea/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Vasodilatadores/efeitos adversos
14.
Trials ; 20(1): 255, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31053082

RESUMO

BACKGROUND: Hypotension is associated with serious complications, including myocardial infarction, acute kidney injury, and mortality. Consequently, predicting and preventing hypotension may improve outcomes. We will therefore determine if use of a novel hypotension prediction tool reduces the duration and severity of hypotension in patients having non-cardiac surgery. METHODS/DESIGN: We will conduct a two-center, pragmatic, randomized controlled trial (N = 213) in noncardiac surgical patients > 45 years old who require intra-arterial blood pressure monitoring. All participating patients will be connected to a Flortrac IQ sensor and EV1000 platform (Edwards Lifesciences, Irvine). They will be randomly assigned to blinded or unblinded arms. The Hypotension Prediction Index (HPI) and advanced hemodynamic information will be universally recorded, but will only be available to clinicians when patients are assigned to unblinded monitoring. The primary outcome will be the effect of HPI software guidance on intraoperative time-weighted average mean arterial pressure under a threshold of 65 mmHg, which will be assessed with a Wilcoxon-Mann-Whitney 2-sample, two-tailed test. DISCUSSION: Our trial will determine whether the Hypotension Prediction Index and associated hemodynamic information substantively reduces hypotension during non-cardiac surgery. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03610165 . Registered on 1 August 2018.


Assuntos
Pressão Arterial , Determinação da Pressão Arterial , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Hipotensão/prevenção & controle , Monitorização Intraoperatória/métodos , Software , Feminino , Humanos , Hipotensão/diagnóstico , Hipotensão/etiologia , Hipotensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Ohio , Ensaios Clínicos Pragmáticos como Assunto , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
15.
Transfusion ; 59(S2): 1529-1538, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30980755

RESUMO

Traumatic brain injury (TBI) is a common disorder with high morbidity and mortality, accounting for one in every three deaths due to injury. Older adults are especially vulnerable. They have the highest rates of TBI-related hospitalization and death. There are about 2.5 to 6.5 million US citizens living with TBI-related disabilities. The cost of care is very high. Aside from prevention, little can be done for the initial primary injury of neurotrauma. The tissue damage incurred directly from the inciting event, for example, a blow to the head or bullet penetration, is largely complete by the time medical care can be instituted. However, this event will give rise to secondary injury, which consists of a cascade of changes on a cellular and molecular level, including cellular swelling, loss of membrane gradients, influx of immune and inflammatory mediators, excitotoxic transmitter release, and changes in calcium dynamics. Clinicians can intercede with interventions to improve outcome in the mitigating secondary injury. The fundamental concepts in critical care management of moderate and severe TBI focus on alleviating intracranial pressure and avoiding hypotension and hypoxia. In addition to these important considerations, mechanical ventilation, appropriate transfusion of blood products, management of paroxysmal sympathetic hyperactivity, using nutrition as a therapy, and, of course, venous thromboembolism and seizure prevention are all essential in the management of moderate to severe TBI patients. These concepts will be reviewed using the recent 2016 Brain Trauma Foundation Guidelines to discuss best practices and identify future research priorities.


Assuntos
Transfusão de Componentes Sanguíneos , Lesões Encefálicas Traumáticas , Cuidados Críticos/métodos , Hospitalização , Adulto , Idoso , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/mortalidade , Lesões Encefálicas Traumáticas/fisiopatologia , Lesões Encefálicas Traumáticas/terapia , Feminino , Humanos , Hipotensão/etiologia , Hipotensão/mortalidade , Hipotensão/fisiopatologia , Hipotensão/prevenção & controle , Hipóxia Encefálica/etiologia , Hipóxia Encefálica/mortalidade , Hipóxia Encefálica/fisiopatologia , Hipóxia Encefálica/prevenção & controle , Hipertensão Intracraniana/etiologia , Hipertensão Intracraniana/mortalidade , Hipertensão Intracraniana/fisiopatologia , Hipertensão Intracraniana/prevenção & controle , Masculino , Pessoa de Meia-Idade , Convulsões/etiologia , Convulsões/mortalidade , Convulsões/fisiopatologia , Convulsões/prevenção & controle , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/mortalidade , Tromboembolia Venosa/fisiopatologia , Tromboembolia Venosa/prevenção & controle
16.
Transplant Proc ; 51(3): 951-959, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30979488

RESUMO

BACKGROUND: We aimed to observe the effect of hypotensive brain death on the donor liver and understand its pathophysiological mechanism in improved pig model. METHODS: The model was induced using the modified intracranial water sac inflation method in 16 Bama miniature pigs. Effects of hypotensive brain death on liver function and tissue morphology were evaluated via changes in liver function enzyme index, liver tissue alkaline phosphatase levels, hourly bile flow, and liver tissue pathology. Its pathophysiological mechanism was examined on the basis of changes in portal vein blood flow, hepatic artery blood flow, portal venous endotoxin level, and liver tissue cytokine levels. RESULTS: After model establishment, portal vein blood flow, hepatic arterial blood flow, hourly bile flow, and alkaline phosphatase content in hepatic tissue significantly decreased, and serum aspartate aminotransferase, alkaline phosphatase, and lactate dehydrogenase levels significantly increased. Hematoxylin-eosin staining of liver tissue showed that after model establishment, hepatic tissue injury was gradually aggravated and hepatic cells were irreversibly damaged at 7 hours. Portal vein endotoxin levels significantly increased after brain death. Tumor necrosis factor α, interleukin 1, and endothelin 1 levels in liver tissues significantly increased at 3, 6, and 12 hours after brain death (P < .05), and hypoxia-inducible factor 1-α and nitric oxide levels significantly decreased (P < .05). CONCLUSIONS: Hepatic injury was progressively aggravated under hypotensive brain death. The mechanism of donor liver injury under hypotensive brain death may involve low liver perfusion, release of intestinal endotoxin and inflammatory factors (eg, tumor necrosis factor α and interleukin 1), decreased hypoxia-inducible factor 1-α, and endothelin 1 and nitric oxide imbalance.


Assuntos
Morte Encefálica/patologia , Artéria Hepática/fisiopatologia , Hipotensão/fisiopatologia , Transplante de Fígado , Fígado/irrigação sanguínea , Veia Porta/fisiopatologia , Animais , Morte Encefálica/fisiopatologia , Modelos Animais de Doenças , Feminino , Perfusão , Suínos , Porco Miniatura
17.
Crit Care ; 23(1): 118, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30987647

RESUMO

BACKGROUND: We hypothesized that the cardiovascular responses to Surviving Sepsis Guidelines (SSG)-defined resuscitation are predictable based on the cardiovascular state. METHODS: Fifty-five septic patients treated by SSG were studied before and after volume expansion (VE), and if needed norepinephrine (NE) and dobutamine. We measured mean arterial pressure (MAP), cardiac index (CI), and right atrial pressure (Pra) and calculated pulse pressure and stroke volume variation (PPV and SVV), dynamic arterial elastance (Eadyn), arterial elastance (Ea) and left ventricular (LV) end-systolic elastance (Ees), Ees/Ea (VAC), LV ejection efficiency (LVeff), mean systemic pressure analogue (Pmsa), venous return pressure gradient (Pvr), and cardiac performance (Eh), using standard formulae. RESULTS: All patients were hypotensive (MAP 56.8 ± 3.1 mmHg) and tachycardic (113.1 ± 7.5 beat min-1), with increased lactate levels (lactate = 5.0 ± 4.2 mmol L-1) with a worsened VAC. CI was variable but > 2 L min-1 M-2 in 74%. Twenty-eight-day mortality was 48% and associated with admission lactate, blood urea nitrogen (BUN), and creatinine levels but not cardiovascular state. In all patients, both MAP and CI improved following VE, as well as cardiac contractility (Ees). Fluid administration improved Pra, Pmsa, and Pvr in all patients, whereas both HR and Ea decreased after VE, thus normalizing VAC. CI increases were proportional to baseline PPV and SVV. CI increases proportionally decreased PPV and SVV. VE increased MAP > 65 mmHg in 35/55 patients. MAP responders had higher PPV, SVV, and Eadyn than non-responders. NE was given to 20/55 patients in septic shock, but increased MAP > 65 mmHg in only 12. NE increased Ea, Eadyn, Pra, Pmsa, and VAC while decreasing HR, PPV, SVV, and LVeff. MAP responders had higher pre-NE Ees and lower VAC. Dobutamine was given to 6/8 patients who remained hypotensive following NE. It increased Ees, MAP, CI, and LVeff, while decreasing HR, Pra, and VAC. At all times and all steps of the protocol, CI changes were proportional to Pvr changes independent of treatment. CONCLUSIONS: The cardiovascular response to SSG-based resuscitation is highly heterogeneous but predictable from pre-treatment measures of cardiovascular state.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Ressuscitação/normas , Sepse/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Débito Cardíaco/fisiologia , Cardiotônicos/uso terapêutico , Dobutamina/uso terapêutico , Feminino , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Humanos , Hipotensão/tratamento farmacológico , Hipotensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Norepinefrina/uso terapêutico , Ressuscitação/métodos , Ressuscitação/estatística & dados numéricos , Sepse/tratamento farmacológico , Choque Séptico/tratamento farmacológico , Choque Séptico/fisiopatologia , Estatísticas não Paramétricas , Volume Sistólico/fisiologia , Vasoconstritores/uso terapêutico
18.
Anesth Analg ; 128(4): 759-771, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30883421

RESUMO

There are occasionally intraoperative circumstances in which reduction of mean arterial pressure (MAP) to levels well below those that occur in nonanesthetized adults is necessary or unavoidable. In these situations, clinicians are inevitably concerned about the limits of the tolerance of the brain for hypotension. Reference to the phenomenon of cerebral blood flow autoregulation is frequently made in discussions of safe MAP limits. However, in several respects, prevalent conceptions about cerebral blood flow autoregulation may be incomplete or inaccurate. The principal theses offered by this review are: (1) that the average lower limit of cerebral blood flow autoregulation in normotensive adult humans is not less than a MAP of 70 mm Hg; (2) that there is considerable intersubject variability in both the lower limit of cerebral blood flow autoregulation and the efficiency of cerebral blood flow autoregulation; (3) that there is a substantial blood flow reserve that buffers the normal central nervous system against critical blood flow reduction in the face of hypotension; (4) that there are several common clinical phenomena that have the potential to compromise that buffer, and that should be taken into account in decision making about minimum acceptable MAPs; and (5) that the average threshold for the onset of central nervous system ischemic symptoms is probably a MAP of 40-50 mm Hg at the level of the circle of Willis in a normotensive adult in a vertical posture and 45-55 mm Hg in a supine subject. However, these MAPs should probably only be approached deliberately when the exigencies of the surgical situation absolutely require it.


Assuntos
Pressão Sanguínea , Encéfalo/patologia , Circulação Cerebrovascular , Hipotensão/fisiopatologia , Pressão Arterial , Determinação da Pressão Arterial , Isquemia Encefálica/patologia , Homeostase/fisiologia , Humanos , Período Intraoperatório , Monitorização Intraoperatória , Oximetria , Posicionamento do Paciente , Reprodutibilidade dos Testes
19.
Br J Anaesth ; 122(5): 563-574, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30916004

RESUMO

BACKGROUND: Intraoperative mortality is now rare, but death within 30 days of surgery remains surprisingly common. Perioperative myocardial infarction is associated with a remarkably high mortality. There are strong associations between hypotension and myocardial injury, myocardial infarction, renal injury, and death. Perioperative arterial blood pressure management was thus the basis of a Perioperative Quality Initiative consensus-building conference held in London in July 2017. METHODS: The meeting featured a modified Delphi process in which groups addressed various aspects of perioperative arterial pressure. RESULTS: Three consensus statements on intraoperative blood pressure were established. 1) Intraoperative mean arterial pressures below 60-70 mm Hg are associated with myocardial injury, acute kidney injury, and death. Injury is a function of hypotension severity and duration. 2) For adult non-cardiac surgical patients, there is insufficient evidence to recommend a general upper limit of arterial pressure at which therapy should be initiated, although pressures above 160 mm Hg have been associated with myocardial injury and infarction. 3) During cardiac surgery, intraoperative systolic arterial pressure above 140 mm Hg is associated with increased 30 day mortality. Injury is a function of arterial pressure severity and duration. CONCLUSIONS: There is increasing evidence that even brief durations of systolic arterial pressure <100 mm Hg and mean arterial pressure <60-70 mm Hg are harmful during non-cardiac surgery.


Assuntos
Pressão Sanguínea/fisiologia , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Hipotensão/complicações , Complicações Intraoperatórias/fisiopatologia , Lesão Renal Aguda/etiologia , Humanos , Hipotensão/fisiopatologia , Monitorização Intraoperatória/métodos , Infarto do Miocárdio/etiologia , Complicações Pós-Operatórias/etiologia
20.
Br J Anaesth ; 122(5): 575-586, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30916008

RESUMO

BACKGROUND: Postoperative hypotension and hypertension are frequent events associated with increased risk of adverse outcomes. However, proper assessment and management is often poorly understood. As a part of the PeriOperative Quality Improvement (POQI) 3 workgroup meeting, we developed a consensus document addressing this topic. The target population includes adult, non-cardiac surgical patients in the postoperative phase outside of the ICU. METHODS: A modified Delphi technique was used, evaluating papers published in MEDLINE examining postoperative blood pressure monitoring, management, and outcomes. Practice recommendations were developed in line with National Institute for Health and Care Excellence guidelines. RESULTS: Consensus recommendations were that (i) there is evidence of harm associated with postoperative systolic arterial pressure <90 mm Hg; (ii) for patients with preoperative hypertension, the threshold at which harm occurs may be higher than a systolic arterial pressure of 90 mm Hg; (iii) there is insufficient evidence to precisely define the level of postoperative hypertension above which harm will occur; (iv) a greater frequency of postoperative blood pressure measurement is likely to identify risk of harm and clinical deterioration earlier; and (v) there is evidence of harm from withholding beta-blockers, angiotensin receptor blockers, and angiotensin-converting enzyme inhibitors in the postoperative period. CONCLUSIONS: Despite evidence of associations with postoperative hypotension or hypertension with worse postoperative outcome, further research is needed to define the optimal levels at which intervention is beneficial, to identify the best methods and timing of postoperative blood pressure measurement, and to refine the management of long-term antihypertensive treatment in the postoperative phase.


Assuntos
Pressão Sanguínea/fisiologia , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Hipertensão/complicações , Hipotensão/complicações , Complicações Pós-Operatórias/fisiopatologia , Anti-Hipertensivos/uso terapêutico , Determinação da Pressão Arterial/métodos , Determinação da Pressão Arterial/normas , Técnica Delfos , Medicina Baseada em Evidências/métodos , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Hipotensão/diagnóstico , Hipotensão/fisiopatologia , Assistência Perioperatória/métodos , Assistência Perioperatória/normas , Prognóstico , Medição de Risco/métodos
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