RESUMO
The validity of the Dinamap automated oscillometric blood pressure monitor, an instrument frequently used for continuous monitoring in intensive care settings, was evaluated in comparison to two standard methods of blood pressure measurement. Oscillometric monitoring was compared to random-zero sphygmomanometry in 28 ambulatory subjects, using the instruments in a random order. The oscillometric monitor overestimated random-zero systolic pressure (mean difference = 5.7 mm Hg; P less than 0.001), but did not differ in diastolic pressure (difference = 1.3 mm Hg, P greater than 0.3). Correlation (r) between methods was 0.94 for systolic pressure and 0.83 for diastolic pressure. Repeatability of sequential measures did not differ between methods. To evaluate the oscillometric monitor in the intraoperative setting, it was used simultaneously with a radial artery catheter to measure blood pressure in 14 patients undergoing peripheral vascular or other major surgery. The oscillometric monitor underestimated intra-arterial systolic pressure (mean difference = -9.4 mm Hg; P less than 0.002), but overestimated intraarterial diastolic pressure (difference = 5.7 mm Hg; P less than 0.005). There was no difference in mean arterial pressure (P greater than 0.1). Correlation between methods was 0.88 for systolic, 0.71 for diastolic, and 0.79 for mean arterial pressure. The oscillometric instrument had a sensitivity of 63% and specificity of 97% in detecting intraarterial systolic pressures of 160 mm Hg or greater, and a sensitivity of 89% and specificity of 89% in detecting intraarterial systolic pressures of 100 mm Hg or less. These findings demonstrate differences between the oscillometric monitor and other standard methods of blood pressure measurement.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Pressão Sanguínea , Monitorização Fisiológica/instrumentação , Artérias , Cateterismo , Estudos de Avaliação como Assunto , Humanos , Manometria/métodos , Monitorização Fisiológica/métodos , Oscilometria , Análise de RegressãoRESUMO
This limited discussion focuses on the apparent magnitude of the importance of NO-related mechanisms in the maintenance of blood flow to a number of tissue beds, the exaggerated effects in cirrhotics, its effects on platelets and immune modulation, and the potential for manipulation with agonists and antagonists. The possibility of pharmacologic control of this system may play a significant role in the management of patients with liver disease, whether for the treatment of the hypotension associated with low SVR, or endotoxemia/sepsis, or the pulmonary hypertension seen in approximately 1.6% of liver transplant candidates. This is a complex, heavily interrelated system, and the veracity of these various experimental claims for NO needs to be thoroughly evaluated for clinical relevance.
Assuntos
Plaquetas/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Sistema Nervoso Central/fisiologia , Hepatopatias/fisiopatologia , Óxido Nítrico/metabolismo , Fluxo Sanguíneo Regional , Aminoácido Oxirredutases/metabolismo , Endotélio Vascular/fisiologia , Homeostase , Humanos , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase , Resistência VascularAssuntos
Hidratação/mortalidade , Bombas de Infusão/efeitos adversos , Ferimentos e Lesões/terapia , Adulto , Ensaios Clínicos Controlados como Assunto/métodos , Cuidados Críticos , Feminino , Hidratação/efeitos adversos , Hidratação/métodos , Humanos , Masculino , Maryland , Estudos Retrospectivos , Taxa de Sobrevida , Centros de Traumatologia , Ferimentos e Lesões/mortalidadeAssuntos
Ciclosporinas/efeitos adversos , Rim/patologia , Transplante de Fígado , Adolescente , Corticosteroides/uso terapêutico , Adulto , Azatioprina/uso terapêutico , Criança , Pré-Escolar , Creatinina/sangue , Ciclosporinas/uso terapêutico , Quimioterapia Combinada , Humanos , Rim/efeitos dos fármacos , Pessoa de Meia-IdadeRESUMO
The management of patients with fulminant hepatic failure is a major clinical endeavor. Early intensive care at an institution able to perform liver transplantation is essential. It is recognized that therapy focused solely on attempts at preventing/reversing increased intracranial pressure, and the treatment of other failing organs as they occur falls well short of ideal. This review covers the non-biological and biological techniques utilized in efforts to support liver function. The goal is to foster recovery, or to buy enough time for successful liver transplantation. Prospective, controlled trials are beginning to acknowledge subgroups of fulminant hepatic failure and properly randomize therapy. Our understanding of the essential elements of liver support is improving, but no single device has yet proved indispensable.
RESUMO
By making the clinical decision making process explicit, conscious, and science based, we may avoid confusing opinion with evidence. EBM may help sharpen our critical appraisal skills and thus improve the way we practice, teach, and conduct research. Nevertheless, EBM will need to supplement rather than substitute for other approaches to patient care and teaching. EBM may better incorporate patients' values into clinical decision making, and this may be especially important in anesthesiology, where we are in need of valid evidence about important clinical issues such as preoperative testing and postoperative analgesia. By incorporating valid scientific evidence and patients' values into clinical decision making, we may improve patient outcomes. Outside of internal medicine, the literature suggesting that the practice of EBM improves outcomes is sparse, though increasing. Future studies to critically evaluate the practice of EBM in anesthesiology and critical care would be helpful.
Assuntos
Anestesiologia , Medicina Baseada em Evidências , HumanosRESUMO
OBJECTIVE: To test the hypothesis that preoperative lumbar epidural morphine improves postoperative pain control and ventilatory function after transsternal thymectomy in patients with myasthenia gravis. DESIGN: The study design was randomized, placebo-controlled, and double-blind. SETTING: After surgery, all patients were admitted to the Neuroscience Critical Care Unit for evaluation and treatment. PATIENTS: All patients with myasthenia gravis who presented to the hospital for thymectomy were asked to participate in the study. Twenty patients were randomized to either the placebo or epidural morphine groups. INTERVENTIONS: Patients received either epidural morphine (7 mg in 14 mL of sterile saline) or saline (14 mL) before induction of anesthesia. Supplemental iv opioids were administered intraoperatively, with need determined by the anesthesiologist. MAIN OUTCOME MEASURES: The main outcome measures were indicators of postoperative pain (e.g., Visual Analog Pain Score, requirement for supplemental opioid administration, respiratory rate) and ventilatory function (e.g., forced vital capacity, negative inspiratory pressure). RESULTS: Immediately after surgery, the Visual Analog Pain Score in the placebo group was twice as high as the score in the epidural morphine group (placebo 7.0 +/- 1.3; epidural morphine 3.5 +/- 1.2, p less than or equal to .05). During the first eight postoperative hours, the placebo group required more opioids (0.22 +/- 0.03 vs. 0.12 +/- 0.04 mg/kg morphine equivalents, p less than or equal to .06) than the epidural morphine group. Later, both groups received similar amounts of opioids. Patients receiving epidural morphine had better initial recovery of forced vital capacity (at 8 hrs: 55 +/- 6% [epidural morphine] vs. 34 +/- 5% [placebo] of preoperative value, p less than or equal to .05). Respiratory rate was lower for the first 12 postoperative hours in the epidural morphine group, without a difference in PaCO2. There was no difference between groups for the duration of postoperative intubation or ventilation. CONCLUSIONS: Preoperative lumbar epidural morphine facilitates postoperative analgesia and improves initial postoperative ventilatory performance.
Assuntos
Analgesia Epidural/normas , Morfina/uso terapêutico , Miastenia Gravis/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Medicação Pré-Anestésica/normas , Respiração Artificial/normas , Timectomia/métodos , Adulto , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Injeções Intravenosas , Masculino , Monitorização Fisiológica , Morfina/administração & dosagem , Miastenia Gravis/fisiopatologia , Miastenia Gravis/terapia , Entorpecentes/administração & dosagem , Entorpecentes/uso terapêutico , Medição da Dor , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/fisiopatologia , Estudos Prospectivos , Respiração , Fatores de Tempo , Resultado do Tratamento , Capacidade VitalRESUMO
Budd-Chiari syndrome (BCS) is a rare form of portal hypertension characterized by hepatic venous outflow obstruction. Although hematologic disorders are the most common cause of this syndrome, to date, 30% of the cases have been classified as idiopathic. Resistance to activated protein C caused by factor V Leiden is the most common cause of thrombophilia; its role in the pathogenesis of BCS is now becoming apparent. We report successful liver transplantation in a patient with BCS caused by homozygous factor V Leiden. The patient was administered standard heparin anticoagulation until activated protein C resistance was normalized by the liver allograft. Liver transplantation corrected the thrombophilic state. The patient has excellent graft function, is not on anticoagulation therapy, and has had no recurrent venous thrombosis at 5 months posttransplantation. Activated protein C resistance caused by the factor V Leiden mutation may be responsible for idiopathic cases of BCS. To avoid unnecessary long-term anticoagulation after liver transplantation, factor V Leiden should be considered as a pathogenic factor in BCS. In addition, because of the high prevalence of factor V Leiden in the world population, cadaveric organ donors with a history of venous thrombosis should be screened for activated protein C resistance lest thrombophilia be transmitted to the recipient.
Assuntos
Síndrome de Budd-Chiari/genética , Síndrome de Budd-Chiari/cirurgia , Fator V/genética , Homozigoto , Transplante de Fígado , Adulto , Anticoagulantes/uso terapêutico , Síndrome de Budd-Chiari/fisiopatologia , Resistência a Medicamentos , Feminino , Heparina/uso terapêutico , Humanos , Proteína C/fisiologia , Resultado do TratamentoRESUMO
Partial veno-venous bypass (VVB) is commonly used in orthotopic liver transplantation (OLT). Venous access for blood return during VVB classically uses a surgical cutdown on the left axillary vein (LAV), which may prolong operating time and can be associated with significant complications. The authors have developed an alternative means of establishing venous access whereby the anesthesia team places 8.5F venous cannulae preoperatively in one or two vessels (internal jugular, antecubital, or subclavian) percutaneously using the Seldinger technique. These cannulae then serve to accept venous return from below the diaphragm via a centrifugal pump. The aim fo the present study was to compare the hemodynamic profiles obtained during the anhepatic phase of OLT in patients in whom either a conventional LAV catheter (group 1) or percutaneous catheters (group 2) were used for return flow from a centrifugal pump. There were no identifiable complications related to venous access in either group of patients. Total operating room time was 800 +/- 30 minutes in group 1 and 720 +/- 40 minutes in group 2 (P = 0.17). Hemodynamic parameters were determined from continuous strip chart recordings of arterial, right atrial, and inferior vena caval (IVCP) pressures. Cardiac output (CO) was measured by thermodilution whereas pump flow was determined by an electromagnetic probe. Renal perfusion pressure (RPP) was calculated as the difference between mean arterial pressure (MAP) and IVCP. Bypass pump flow was greater, but not significantly different between group 1 (3.0 +/- 0.2 L/min) and group 2 (2.4 +/- 0.2 L/min) (P = 0.09).(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Cateteres de Demora , Transplante de Fígado , Venostomia , Veia Axilar/cirurgia , Pressão Sanguínea , Transfusão de Sangue , Débito Cardíaco , Cateterismo Venoso Central , Pressão Venosa Central , Cotovelo/irrigação sanguínea , Veia Femoral/cirurgia , Frequência Cardíaca , Artéria Hepática/cirurgia , Humanos , Veias Jugulares/cirurgia , Oxigenadores , Veia Porta/cirurgia , Veia Subclávia/cirurgia , Fatores de Tempo , Veias/cirurgia , Veia Cava Inferior/cirurgiaRESUMO
We observed the comparative serum levels and mean peak serum antistaphylococcal activity in eight fasting adults who received 500 mg each of dicloxacillin, cloxacillin, oxacillin, and nafcillin. Dicloxacillin achieved higher and more prolonged serum levels and greater peak serum antistaphylococcal titers than the other drugs studied. The higher degree of protein binding of dicloxacillin was reflected in a greater disparity between the peak antistaphylococcal activity observed when dilutions were done in serum compared to broth. The lesser protein-bound penicillins showed less disparity, but this effect was offset by the higher serum levels obtained by dicloxacillin. The higher protein binding of dicloxacillin did not prevent its having equal or superior antistaphylococcal activity in serum when the drugs were given in equal doses.
Assuntos
Cloxacilina/sangue , Dicloxacilina/sangue , Nafcilina/sangue , Oxacilina/sangue , Penicilinase/metabolismo , Penicilinas/sangue , Staphylococcus/efeitos dos fármacos , beta-Lactamases/metabolismo , Administração Oral , Adulto , Ensaios Clínicos como Assunto , Cloxacilina/metabolismo , Dicloxacilina/metabolismo , Humanos , Nafcilina/metabolismo , Oxacilina/metabolismo , Penicilinas/metabolismo , Ligação ProteicaRESUMO
Portopulmonary hypertension (PPHTN) is no longer an absolute contraindication to orthotopic liver transplantation (OLT). The pre-OLT management of patients with PPHTN requires early diagnosis and chronic therapy with intravenous epoprostenol to decrease pulmonary vascular resistance (PVR). Close follow-up is necessary to reassess pulmonary artery pressures (PAPs) and evaluate right ventricular (RV) function. This assists in the optimal timing of OLT. Successful management also necessitates reassessment of pulmonary artery hemodynamics just before OLT, with clearly defined parameters used to determine whether to proceed. Even with the intraoperative and postoperative availability of potent pulmonary vasodilators, clinical management may be suboptimal in reducing PAP. Adequate reduction in PVR and improvement in RV function in response to chronic epoprostenol therapy may facilitate successful OLT. We present a case report and review the limited experience with this treatment.