Francisco Esteve

Short-term independent mortality risk factors in patients with cirrhosis undergoing cardiac surgery

OBJECTIVES Cirrhosis represents a serious risk in patients undergoing cardiac surgery. Several preoperative factors identify cirrhotic patients as high risk for cardiac surgery; however, a patients preoperative status may be modified by surgical intervention and, as yet, no independent postoperative mortality risk factors have been identified in this setting. The objective of this study was to identify preoperative and postoperative mortality risk factors and the scores that are the best predictors of short-term risk. METHODS Fifty-eight consecutive cirrhotic patients requiring cardiac surgery between January 2004 and January 2009 were prospectively studied at our institution. Forty-two (72%) patients were operated on for valve replacement, 9 (16%) for a CABG and 7 (12%) for both (CABG and valve replacement). Thirty-four (58%) patients were classified as Child-Turcotte-Pugh class A, 21 (36%) as class B and 3 (5%) as class C. We evaluated the variables that are usually measured on admission and during the first 24 h of the postoperative period together with potential operative predictors of outcome, such as cardiac surgery scores (Parsonnet, EuroSCORE), liver scores (Child-Turcotte-Pugh, model for end-stage liver disease, United Kingdom end-stage liver disease score) and ICU scores (acute physiology and chronic health evaluation II and III, simplified acute physiology score II and III, sequential organ failure assessment). RESULTS Seven patients (12%) died in-hospital, of whom 5 were Child-Turcotte-Pugh class B and 2 class C. Comparing survivors vs non-survivors, univariate analysis revealed that variables associated with short-term outcome were international normalized ratio (1.5 ± 0.24 vs 2.2 ± 0.11, P < 0.0001), presurgery platelet count (171 ± 87 vs 113 ± 52 l nl(-1), P = 0.031), presurgery haemoglobin count (11.8 ± 1.8 vs 10.2 ± 1.4 g dl(-1), P = 0.021), total need for erythrocyte concentrates (2 ± 3.4 vs 8.5 ± 8 units, P < 0.0001), PaO(2)/FiO(2) at 12 h after ICU admission (327 ± 84 vs 257 ± 78, P = 0.04), initial central venous pressure (11 ± 3 vs 16 ± 4 mmHg, P = 0.02) and arterial blood lactate concentration 24 h after admission (1.8 ± 0.5 vs 2.5 ± 1.3 mmol l(-1), P = 0.019). Multivariate analysis identified initial central venous pressure as the only independent factor associated with short-term outcome (P = 0.027). The receiver operating characteristic curve showed that the model for end-stage Liver disease score had a better predictive value for short-term outcome than other scores (AUC: 90.5 ± 4.4%; sensitivity: 85.7%; specificity: 83.7%), although simplified acute physiology score III was acceptable. CONCLUSIONS We conclude that central venous pressure could be a valuable predictor of short-term outcome in patients with cirrhosis undergoing cardiac surgery. The model for end-stage liver disease score is the best predictor of cirrhotic patients who are at high risk for cardiac surgery. Sequential organ failure assessment and simplified acute physiology score III are also valuable predictors.

Influence of cirrhosis in cardiac surgery outcomes.

Liver cirrhosis has evolved an important risk factor for cardiac surgery due to the higher morbidity and mortality that these patients may suffer compared with general cardiac surgery population. The presence of contributing factors for a poor outcome, such as coagulopathy, a poor nutritional status, an adaptive immune dysfunction, a degree of cirrhotic cardiomyopathy, and a degree of renal and pulmonary dysfunction, have to be taken into account for surgical evaluation when cardiac surgery is needed, together with the degree of liver disease and its primary complications. The associated pathophysiological characteristics that liver cirrhosis represents have a great influence in the development of complications during cardiac surgery and the postoperative course. Despite the population of cirrhotic patients who are referred for cardiac surgery is small and recommendations come from small series, since liver cirrhotic patients have increased their chance of survival in the last 20 years due to the advances in their medical care, which includes liver transplantation, they have been increasingly considered for cardiac surgery. Indeed, there is an expected rise of cirrhotic patients within the cardiac surgical population due to the increasing rates of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis, especially in western countries. In consequence, a more specific approach is needed in the assessment of care of these patients if we want to improve their management. In this article, we review the pathophysiology and outcome prediction of cirrhotic patients who underwent cardiac surgery.

Evaluation of Serial Arterial Lactate Levels as a Predictor of Hospital and Long-Term Mortality in Patients After Cardiac Surgery

OBJECTIVES Although hyperlactatemia is common after cardiac surgery, its value as a prognostic marker is unclear. The aim of the present study was to determine whether postoperative serial arterial lactate (AL) measurements after cardiac surgery could predict outcome. DESIGN Prospective, observational study. SETTING Surgical intensive care unit in a tertiary-level university hospital. PARTICIPANTS Participants included 2,935 consecutive patients. INTERVENTIONS AL was measured on admission to the intensive care unit and 6, 12, and 24 hours after surgery, and evaluated together with clinical data and outcomes including in-hospital and long-term mortality. MEASUREMENTS AND MAIN RESULTS In-hospital and long-term mortality (mean follow-up 6.3±1.7 years) were 5.9% and 8.7%, respectively. Compared with survivors, nonsurvivors showed higher mean AL values in all measurements (p<0.001). Hyperlactatemia (AL>3.0 mmol/L) was a predictor for in-hospital mortality (odds ratio = 1.468; 95% confidence interval = 1.239-1.739; p<0.001) and long-term mortality (hazard ratio = 1.511; 95% confidence interval = 1.251-1.825; p<0.001). Recent myocardial infarction and longer cardiopulmonary bypass time were predictors of hyperlactatemia. The pattern of AL dynamics was similar in both groups, but nonsurvivors showed higher AL values, as confirmed by repeated measures analysis of variance (p<0.001). The area under the curve also showed higher levels of AL in nonsurvivors (80.9±68.2 v 49.71±25.8 mmol/L/h; p = 0.038). Patients with hyperlactatemia were divided according to their timing of peak AL, with higher mortality and worse survival in patients in whom AL peaked at 24 hours compared with other groups (79.1% v 86.7%-89.2%; p = 0.03). CONCLUSIONS The dynamics of the postoperative AL curve in patients undergoing cardiac surgery suggests a similar mechanism of hyperlactatemia in survivors and nonsurvivors, albeit with a higher production or lower clearance of AL in nonsurvivors. The presence of a peak of hyperlactatemia at 24 hours is associated with higher in-hospital and long-term mortality.

Outcomes of abdominal surgery in patients with liver cirrhosis.

Patients suffering from liver cirrhosis (LC) frequently require non-hepatic abdominal surgery, even before liver transplantation. LC is an important risk factor itself for surgery, due to the higher than average associated morbidity and mortality. This high surgical risk occurs because of the pathophysiology of liver disease itself and to the presence of contributing factors, such as coagulopathy, poor nutritional status, adaptive immune dysfunction, cirrhotic cardiomyopathy, and renal and pulmonary dysfunction, which all lead to poor outcomes. Careful evaluation of these factors and the degree of liver disease can help to reduce the development of complications both during and after abdominal surgery. In the emergency setting, with the presence of decompensated LC, alcoholic hepatitis, severe/advanced LC, and significant extrahepatic organ dysfunction conservative management is preferred. A multidisciplinary, individualized, and specialized approach can improve outcomes; preoperative optimization after risk stratification and careful management are mandatory before surgery. Laparoscopic techniques can also improve outcomes. We review the impact of LC on surgical outcome in non-hepatic abdominal surgeries required in this cirrhotic population before, during, and after surgery.

Higher requirements of dialysis in severe lithium intoxication.

Severe lithium poisoning is a frequent condition in the intoxicated intensive care unit population. Dialysis is the treatment of choice, but no clinical markers predicting higher requirement for dialysis have been identified to date. We analyze the characteristics of lithium overdose patients needing dialysis to improve lithium clearance, and identify the ones associated with higher dialysis requirement. This is an observational, retrospective study of 14 patients with lithium poisoning admitted from 2004 to 2009. Median age was 41.8 ± 16.1 years. Poisonings were acute in 7.1%, acute‐on‐chronic in 64.28%, and chronic in 28.5% of cases. Comparing clinical and biochemical data in patients requiring more than one dialysis session with those requiring only one session, the univariate analysis showed differences at admission in creatinine clearance (40.5 ± 23 vs. 73.3 ± 24.9 mL/min, P = 0.025), white blood cells (17528 ± 3530 vs. 11580 ± 3360 cells/L, P = 0.007), and blood sodium concentration (134.8 ± 5.9 vs. 141.8 ± 8.4 mmol/L, P=0.035). We measured the degree of association between the number of sessions and the variables with partial correlations. High lithium levels (P = 0.006, r = 0.69), low creatinine clearance (P = 0.04, r = −0.55), and low blood sodium concentration (P = 0.024, r = −0.59) were associated with a greater number of dialysis sessions. The correlation remained significant for blood sodium concentration (P = 0.016, r = −0.67) after adjustment for creatinine clearance and initial lithium levels. Presence on admission of low creatinine clearance, low blood sodium concentration, and/or high lithium levels correlated with a higher number of dialysis sessions in severe lithium poisoning. These factors, especially low blood sodium concentration, are associated with higher dialysis requirements in severe lithium intoxication.

OriginalImpacto de un programa de prevención de la bacteriemia relacionada con el catéter en una unidad de cuidados intensivos de un hospital terciarioImpact of a prevention program for catheter-related bloodstream infection in the intensive care unit of a tertiary hospital

INTRODUCTION Catheter-related bloodstream infection (CR-BSI) is a cause of morbidity and mortality in intensive care units, and the optimal approach for preventing these infections is not well defined. Comparison of CR-BSI rates with those provided by programs such as the National Nosocomial Infection Surveillance System (NNISS) from the USA and the Spanish National Nosocomial Infection Surveillance Study (ENVIN), enable determination of the need to implement control measures. In 2000, we found that the CR-BSI rates in UCIs of our hospital were much higher than the data reported by ENVIN. OBJECTIVE To assess the impact of implementing a protocol for proper use of intravascular catheters on CR-BSI rates in the intensive care unit (ICU) of a tertiary hospital. METHODS Prospective study of patients admitted to the ICUs of a tertiary hospital in the months of May and June, from 2000 to 2004. In 2001, a CR-BSI prevention program including aspects related to catheter insertion and maintenance in ICU patients was implemented. We calculated infection rates per 1000 days of catheter use in all the 2-month periods studied, and compared the 2000 and 2004 results by analysis of the odds ratios and confidence intervals. RESULTS A total of 923 patients were included. Mean age was 58.7 years (SD: 15.4), mean ICU stay was 11.6 days (SD: 11.4), mean SAPSII was 28.2 (SD: 15.9), and mortality was 20.5%. There was a significant reduction in CR-BSI rates from 13.3 episodes per 1000 days of catheter use in the first period to 3.21 in the last period (OR=3.53, 95% CI: 2.36-5.31). CONCLUSIONS Application of a prevention program for CR-BSI and a system for monitoring BSI rates led to a significant, sustained reduction in these infections.

Impacto de un programa de prevencion de la bacteriemia relacionada con el cateter en una unidad de cuidados intensivos de un hospital terciario

INTRODUCTION Catheter-related bloodstream infection (CR-BSI) is a cause of morbidity and mortality in intensive care units, and the optimal approach for preventing these infections is not well defined. Comparison of CR-BSI rates with those provided by programs such as the National Nosocomial Infection Surveillance System (NNISS) from the USA and the Spanish National Nosocomial Infection Surveillance Study (ENVIN), enable determination of the need to implement control measures. In 2000, we found that the CR-BSI rates in UCIs of our hospital were much higher than the data reported by ENVIN. OBJECTIVE To assess the impact of implementing a protocol for proper use of intravascular catheters on CR-BSI rates in the intensive care unit (ICU) of a tertiary hospital. METHODS Prospective study of patients admitted to the ICUs of a tertiary hospital in the months of May and June, from 2000 to 2004. In 2001, a CR-BSI prevention program including aspects related to catheter insertion and maintenance in ICU patients was implemented. We calculated infection rates per 1000 days of catheter use in all the 2-month periods studied, and compared the 2000 and 2004 results by analysis of the odds ratios and confidence intervals. RESULTS A total of 923 patients were included. Mean age was 58.7 years (SD: 15.4), mean ICU stay was 11.6 days (SD: 11.4), mean SAPSII was 28.2 (SD: 15.9), and mortality was 20.5%. There was a significant reduction in CR-BSI rates from 13.3 episodes per 1000 days of catheter use in the first period to 3.21 in the last period (OR=3.53, 95% CI: 2.36-5.31). CONCLUSIONS Application of a prevention program for CR-BSI and a system for monitoring BSI rates led to a significant, sustained reduction in these infections.

The Influence of Body Mass Index on Outcomes in Patients Undergoing Cardiac Surgery: Does the Obesity Paradox Really Exist?

Purpose Obesity influences risk stratification in cardiac surgery in everyday practice. However, some studies have reported better outcomes in patients with a high body mass index (BMI): this is known as the obesity paradox. The aim of this study was to quantify the effect of diverse degrees of high BMI on clinical outcomes after cardiac surgery, and to assess the existence of an obesity paradox in our patients. Methods A total of 2,499 consecutive patients requiring all types of cardiac surgery with cardiopulmonary bypass between January 2004 and February 2009 were prospectively studied at our institution. Patients were divided into four groups based on BMI: normal weight (18.5–24.9 kg∙m−2; n = 523; 21.4%), overweight (25–29.9kg∙m−2; n = 1150; 47%), obese (≥30–≤34.9kg∙m−2; n = 624; 25.5%) and morbidly obese (≥35kg∙m−2; n = 152; 6.2%). Follow-up was performed in 2,379 patients during the first year. Results After adjusting for confounding factors, patients with higher BMI presented worse oxygenation and better nutritional status, reflected by lower PaO2/FiO2 at 24h and higher albumin levels 48h after admission respectively. Obese patients showed a higher risk for Perioperative Myocardial Infarction (OR: 1.768; 95% CI: 1.035–3.022; p = 0.037) and septicaemia (OR: 1.489; 95% CI: 1.282–1.997; p = 0.005). In-hospital mortality was 4.8% (n = 118) and 1-year mortality was 10.1% (n = 252). No differences were found regarding in-hospital mortality between BMI groups. The overweight group showed better 1-year survival than normal weight patients (91.2% vs. 87.6%; Log Rank: p = 0.029. HR: 1.496; 95% CI: 1.062–2.108; p = 0.021). Conclusions In our population, obesity increases Perioperative Myocardial Infarction and septicaemia after cardiac surgery, but does not influence in-hospital mortality. Although we found better 1-year survival in overweight patients, our results do not support any protective effect of obesity in patients undergoing cardiac surgery.