Risk Factors of Mortality After Liver Transplantation in Uruguay.

INTRODUCTION: Identification of predictive factors of mortality in a liver transplant (LT) program optimizes patient selection and allocation of organs. OBJECTIVE: To determine survival rates and predictive factors of mortality after LT in the National Liver Transplant Program of Uruguay. METHODS: A retrospective study was conducted analyzing data prospectively collected into a multidisciplinary database. All patients transplanted since the beginning of the program on July 2009 to April 2017 were included (n = 148). Twenty-nine factors were analyzed through the univariate Kaplan-Meier model. A Cox regression model was used in the multivariate analysis to identify the independent prognostic factors for survival. RESULTS: Overall survival was 92%, 87%, and 78% at discharge, 1 year, and 3 years, respectively. The Kaplan-Meier survival curves were significantly lower in: recipients aged >60 years, Model for End-Stage Liver Disease score >21, LT due to hepatocellular carcinoma (HCC) and acute liver failure (ALF), donors with comorbidities, intraoperative blood loss beyond the median (>2350 mL), red blood cell transfusion requirement beyond the median (>1254 mL), intraoperative complications, delay of extubation, invasive bacterial, and fungal infection after LT and stay in critical care unit >4 days. The Cox regression model (likelihood ratio test, P = 1.976 e-06) identified the following independent prognostic factors for survival: LT for HCC (hazard ratio [HR] 4.511; P = .001) and ALF (HR 6.346; P = .004), donors with comorbidities (HR 2.354; P = .041), intraoperative complications (HR 2.707; P = .027), and invasive fungal infections (HR 3.281; P = .025). CONCLUSION: The survival rates of LT patients as well as the mortality-associated factors are similar to those reported in the international literature.

Ultrasound-guided internal jugular vein catheterization: a randomized controlled trial.

INTRODUCTION: Even though advantages of ultrasound line placement seem obvious, many countries do not have easy access to such technology. This study aims to compare the degree of difficulty in central venous line placement with or without ultrasound and the incidence of complications, and to establish the effect of the operator's degree of training. METHODS: The study included 257 patients that required central venous catheterization during the study period. Patients were divided into groups according to the operator's experience: expert group (over 70 central accesses performed before the study) (n=152) and in-training or non-expert group. Procedures were randomized to "without ultrasound" (n=80 expert and 54 non-expert) and "with ultrasound" (n=72 expert and 51 non-expert). RESULTS: Catheter placements were more successful in the "expert" and in the "with ultrasound" than in the "non-expert" (88% vs 79%; p=0.04) or in the "without ultrasound" groups (91% vs 78%; p=0.005). Incidence of complications was 11.7%, with no significant difference among "with ultrasound" (8.1%) and "without ultrasound" (14.9%) groups. However, the "non-expert" group had fewer complications with the use of ultrasound (7.8% vs 24%). CONCLUSIONS: Ultrasound reduces the incidence of complications when placement is performed by inexperienced operators. Centers with residents should emphasize the necessity of ultrasound for central line catheterization. Training in ultrasound might be of paramount importance in the effectiveness of the technique.

Intraoperative hyponatremia during craniofacial surgery.

BACKGROUND: Hyponatremia is an important cause of morbidity in some groups of hospitalized children. Our aim is to describe the incidence and severity of intraoperative hyponatremia in children undergoing craniofacial surgery, and determine the associated risk factors. METHODS: A descriptive retrospective study of children who underwent primary craniofacial surgery between March 1994 and February 2008 was performed. All administered fluids contained a minimum sodium concentration of 140 mmol.l(-1). Hyponatremia was classified as follows: severe < or =125 mmol.l(-1); moderate 126-130 mmol.l(-1); and, mild 131-134 mmol.l(-1). RESULTS: Hundred and seven cases are reported. Severe, moderate and mild intraoperative hyponatremia occurred in 14 (13%), 21 (19%) and 23 (22%) children respectively. Mannitol was given to 31 (29%) children, but was not associated with the development of hyponatremia. Neither the type nor duration of surgery, type of fluid replacement nor hourly urinary output, was associated with development of hyponatremia. Most episodes of significant intraoperative hyponatremia (44%) were detected between the 2nd and the 4th hour of surgery. There were no identified neurological sequelae (e.g. coma, neurological deficit) attributable to the hyponatremia. CONCLUSION: Despite strict avoidance of low sodium solutions (<140 mmol.l(-1)), hyponatremia occurs frequently in children undergoing craniofacial surgery in our practice; and is unrelated to the administration of mannitol. Although the mechanisms are yet to be determined, anesthesiologists should be aware of this issue and be prepared to monitor and treat this potentially serious complication.

Comparación hemodinámica entre isoflurane y sevoflurane en el paciente quemado / Hemodynamic comparison of isoflurane and sevoflurane in the burn patient

Se estudiaron prospectivamente 27 operaciones en 13 pacientes, con una superficie corporal total quemada media de 21 por ciento (10-57). La edad promedio fue de 37 años (16-78). Se excluyeron pacientes con distress respiratorio y/o con repercusión hemodinámica que requirieran drogas vasoactivas. En todos se obtuvo un perfil hemodinámico continuo, en tiempo real y no invasivo del gasto aórtico (GAM), presión arterial media (PAM), resistencia vasculares sistémicas (RVST) e intervalo tiempo sistólicos (ITS), PePi, LVET y relación PePi/LVET. Se inició la anestesia general con sevoflurane o isoflurane en forma randomizada y, en situación estable, se cambió de agente midiendo a los 30 minutos las eventuales repercusiones hemodinámicas. Ninguna de las diferencias fueron estadísticamente significativas. Todos los valores hemodinámicos medios de ambos agentes estuvieron dentro de los rangos de normalidad para esta etapa de los quemados. Como conclusión, parece no haber diferencias hemodinámicas significativas entre ambos agentes en este tipo particular de pacientes estudiado

The inhibitory effect of halothane on the emetic response in the ferret.

Emesis and nausea are often associated with anaesthesia and continue to be a common clinical problem. Past clinical studies have demonstrated that halothane produces a higher incidence of vomiting compared with other anaesthetics, but some investigators have described an antiemetic effect. The purpose of this study was to investigate the effects of various doses of halothane on the emetic response in the decerebrate ferret. Following a control emetic response, a maximum of six increasing cumulative concentrations of halothane were delivered. At the end of each delivery period, the supradiaphragmatic vagal communicating branch, which has been shown to reproducibly elicit vomiting, was electrically stimulated and the emetic response was monitored. An increase in halothane concentration produced a marked depression of tongue, abdominal muscle, and diaphragm EMG activity as well as a decrease in central venous pressure. Licking, a prodromal response comparable to nausea in the human, appeared to be most sensitive. An increase in latency of the emetic response occurred as the concentration of halothane was increased. All phases of the response were observed at concentrations below 0.6 vol% halothane. At 0.6 vol% halothane, 75% of the animals vomited. At higher concentrations, the emetic response was completely abolished. One hour post-halothane, all latencies had returned to near control values. The methods utilized in this study provided a model that was not complicated by a large number of variables usually present in clinical studies. These data demonstrate that halothane exerts an inhibitory, concentration-dependent, and reversible effect on the emetic response in the ferret and provide further support that halothane alone does not possess emetic properties at clinical properties at clinical concentrations.