Fábio Ely Martins Benseñor

Early dexamethasone treatment for septic shock patients: a prospective randomized clinical trial

CONTEXT AND OBJECTIVE Sepsis and septic shock are very common conditions among critically ill patients that lead to multiple organ dysfunction syndrome (MODS) and death. Our purpose was to investigate the efficacy of early administration of dexamethasone for patients with septic shock, with the aim of halting the progression towards MODS and death. DESIGN AND SETTING Prospective, randomized, double-blind, single-center study, developed in a surgical intensive care unit at Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo. METHODS The study involved 29 patients with septic shock. All eligible patients were prospectively randomized to receive either a dose of 0.2 mg/kg of dexamethasone (group D) or placebo (group P), given three times at intervals of 36 hours. The patients were monitored over a seven-day period by means of the sequential organ failure assessment score. RESULTS Patients treated with dexamethasone did not require vasopressor therapy for as much time over the seven-day period as did the placebo group (p = 0.043). Seven-day mortality was 67% in group P (10 out of 15) and 21% in group D (3 out of 14) (relative risk = 0.31, 95% confidence interval 0.11 to 0.88). Dexamethasone enhanced the effects of vasopressor drugs. CONCLUSIONS Early treatment with dexamethasone reduced the seven-day mortality among septic shock patients and showed a trend towards reduction of 28-day mortality.

The Effects of Abdominal Opening on Respiratory Mechanics During General Anesthesia in Normal and Morbidly Obese Patients: A Comparative Study

Morbid obesity has a profound effect on respiratory mechanics and gas exchange. However, most studies were performed in morbidly obese patients before or after anesthesia. We tested the hypothesis that anesthesia and abdominal opening could modify the elastic and resistive properties of the respiratory system. Eleven morbidly obese and eight normal-weight patients scheduled for gastric binding and cancer treatment, respectively, under laparotomy were studied. Respiratory mechanics, partitioned into its lung and chest wall components, were investigated during surgery by means of the end-inspiratory inflation occlusion method and esophageal balloon at five time points. Static respiratory and lung compliance were markedly reduced in obese patients; on the contrary, static compliance of chest wall presented comparable values in both groups. Obese patients also presented higher resistances of the total respiratory system, lung and chest wall, as well as “additional” lung resistance. Mainly in obese patients, laparotomy provoked a significant increase in lung compliance and decrease in “additional” lung resistance 1 h after the peritoneum was opened, which returned to original values after the peritoneum had been closed (P < 0.005). In obese patients, low respiratory compliance and higher airway resistance were mainly determined by the lung component.

Comparison of C-Reactive Protein and Serum Amyloid A Protein in Septic Shock Patients

Septic shock is a severe inflammatory state caused by an infectious agent. Our purpose was to investigate serum amyloid A (SAA) protein and C-reactive protein (CRP) as inflammatory markers of septic shock patients. Here we evaluate 29 patients in postoperative period, with septic shock, in a prospective study developed in a surgical intensive care unit. All eligible patients were monitored over a 7-day period by sequential organ failure assessment (SOFA) score, daily CRP, SAA, and lactate measurements. CRP and SAA strongly correlated up to the fifth day of observation but were not good predictors of mortality in septic shock.

Effects of single dose of dexamethasone on patients with systemic inflammatory response

CONTEXT AND OBJECTIVE Systemic inflammatory response syndrome (SIRS) is a very common condition among critically ill patients. SIRS, sepsis, septic shock and multiple organ dysfunction syndrome (MODS) can lead to death. Our aim was to investigate the efficacy of a single dose of dexamethasone for blocking the progression of systemic inflammatory response syndrome. DESIGN AND SETTING Prospective, randomized, double-blind, single-center study in a postoperative intensive care unit (Surgical Support Unit) at Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo. METHODS The study involved 29 patients with SIRS. All eligible patients were prospectively randomized to receive either a single dose of 0.2 mg/kg of dexamethasone or placebo, after SIRS was diagnosed. The patients were monitored over a seven-day period using Sequential Organ Failure Assessment score (SOFA). RESULTS The respiratory system showed an improvement on the first day after dexamethasone was administered, demonstrated by the improved PaO2/FiO2 ratio (p < 0.05). The cardiovascular system of patients requiring vasopressor therapy also improved over the first two days, with a better evolution in the dexamethasone group (p < 0.05). Non-surviving patients presented higher lactate assays than did survivors (p < 0.05) during this period. CONCLUSIONS Dexamethasone enhanced the effects of vasopressor drugs and evaluation of the respiratory system showed improvements (better PaO2/FiO2 ratio), one day after its administration. Despite these improvements, the single dose of dexamethasone did not block the evolution of SIRS.

A sigmoidal fit for pressure-volume curves of idiopathic pulmonary fibrosis patients on mechanical ventilation: clinical implications

OBJECTIVE: Respiratory pressure-volume curves fitted to exponential equations have been used to assess disease severity and prognosis in spontaneously breathing patients with idiopathic pulmonary fibrosis. Sigmoidal equations have been used to fit pressure-volume curves for mechanically ventilated patients but not for idiopathic pulmonary fibrosis patients. We compared a sigmoidal model and an exponential model to fit pressure-volume curves from mechanically ventilated patients with idiopathic pulmonary fibrosis. METHODS: Six idiopathic pulmonary fibrosis patients and five controls underwent inflation pressure-volume curves using the constant-flow technique during general anesthesia prior to open lung biopsy or thymectomy. We identified the lower and upper inflection points and fit the curves with an exponential equation, V = A-B.e-k.P, and a sigmoid equation, V = a+b/(1+e-(P-c)/d). RESULTS: The mean lower inflection point for idiopathic pulmonary fibrosis patients was significantly higher (10.5±5.7 cm H2O) than that of controls (3.6±2.4 cm H2O). The sigmoidal equation fit the pressure-volume curves of the fibrotic and control patients well, but the exponential equation fit the data well only when points below 50% of the inspiratory capacity were excluded. CONCLUSION: The elevated lower inflection point and the sigmoidal shape of the pressure-volume curves suggest that respiratory system compliance is decreased close to end-expiratory lung volume in idiopathic pulmonary fibrosis patients under general anesthesia and mechanical ventilation. The sigmoidal fit was superior to the exponential fit for inflation pressure-volume curves of anesthetized patients with idiopathic pulmonary fibrosis and could be useful for guiding mechanical ventilation during general anesthesia in this condition.

C-reactive protein is not a useful indicator for infection in surgical intensive care units

CONTEXT AND OBJECTIVE C-reactive protein (CRP) is commonly used as a marker for inflammatory states and for early identification of infection. This study aimed to investigate CRP as a marker for infection in patients with postoperative septic shock. DESIGN AND SETTING Prospective, single-center study, developed in a surgical intensive care unit at Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo. METHODS This study evaluated 54 patients in the postoperative period, of whom 29 had septic shock (SS group) and 25 had systemic inflammatory response syndrome (SIRS group). All of the patients were monitored over a seven-day period using the Sequential Organ Failure Assessment (SOFA) score and daily CRP and lactate measurements. RESULTS The daily CRP measurements did not differ between the groups. There was no correlation between CRP and lactate levels and the SOFA score in the groups. We observed that the plasma CRP concentrations were high in almost all of the patients. The patients presented an inflammatory state postoperatively in response to surgical aggression. This could explain the elevated CRP measurements, regardless of whether the patient was infected or not. CONCLUSIONS This study did not show any correlation between CRP and infection among patients with SIRS and septic shock during the early postoperative period.

Thoracic sympathetic block reduces respiratory system compliance

CONTEXT AND OBJECTIVE Thoracic epidural anesthesia (TEA) following thoracic surgery presents known analgesic and respiratory benefits. However, intraoperative thoracic sympathetic block may trigger airway hyperreactivity. This study weighed up these beneficial and undesirable effects on intraoperative respiratory mechanics. DESIGN AND SETTING Randomized, double-blind clinical study at a tertiary public hospital. METHODS Nineteen patients scheduled for partial lung resection were distributed using a random number table into groups receiving active TEA (15 ml 0.5% bupivacaine, n = 9) or placebo (15 ml 0.9% saline, n = 10) solutions that also contained 1:200,000 epinephrine and 2 mg morphine. Under general anesthesia, flows and airway and esophageal pressures were recorded. Pressure-volume curves, lower inflection points (LIP), resistance and compliance at 10 ml/kg tidal volume were established for respiratory system, chest wall and lungs. Students t test was performed, including confidence intervals (CI). RESULTS Bupivacaine rose 5 +/- 1 dermatomes upwards and 6 +/- 1 downwards. LIP was higher in the bupivacaine group (6.2 +/- 2.3 versus 3.6 +/- 0.6 cmH2O, p = 0.016, CI = -3.4 to -1.8). Respiratory system and lung compliance were higher in the placebo group (respectively 73.3 +/- 10.6 versus 51.9 +/- 15.5, p = 0.003, CI = 19.1 to 23.7; 127.2 +/- 31.7 versus 70.2 +/- 23.1 ml/cmH2O, p < 0.001, CI = 61 to 53). Resistance and chest wall compliance showed no difference. CONCLUSION TEA decreased respiratory system compliance by reducing its lung component. Resistance was unaffected. Under TEA, positive end-expiratory pressure and recruitment maneuvers are advisable.

Lactato como prognóstico de mortalidade e falência orgânica em pacientes com síndrome da resposta inflamatória sistêmica

BACKGROUND AND OBJECTIVES The systemic inflammatory response syndrome (SIRS) is common in the postoperative period of critically ill patients. The objective of this study was to investigate the correlation between lactate level, multiple organ dysfunction, and mortality in patients with SIRS. METHODS This prospective study evaluated 24 patients with a postoperative diagnosis of SIRS (American College of Chest Physicians/Society of Critical Care Medicine) in the surgical ICU. Lactate levels were determined in the first 24 hours after the diagnosis of SIRS and daily, for 7 days. Patients were divided in 2 groups: LE Group (lactate > 2 mmol.L-1) and LN Group (lactate < 2 mmol.L-1). Multiple organ failure was evaluated by the SOFA (Sequential Organ Failure Assessment) score daily, for 7 days. After the 7-day follow-up period patients were followed for up to 28 days, until discharge from the hospital or death. RESULTS Thirteen patients were included in the LE Group after the diagnosis of SIRS and 11 patients in the LN Group. The relative risk (RR) of death in 7 days for the LE Group was 4.23 (CI 95% 2.25-7.95) times greater than in the LN Group in the first day of the study. The RR of death in 28 days was 1.7 times greater for the LE Group (CI 95% 0.84-3.46). The SOFA score was similar in both groups. CONCLUSIONS Patients with elevated lactate in the first 24 hours after the diagnosis of SIRS did not have more organic dysfunction than patients with normal lactate levels, but they had an increased risk of death in 7 days.

Incidência e profilaxia de náuseas e vômitos na recuperação pós-anestésica de um hospital-escola terciário

JUSTIFICATIVA E OBJETIVOS: Nauseas e vomitos pos-operatorios (NVPO) constituem complicacao frequente e potencialmente grave que aumenta o tempo de recuperacao pos-anestesica (RPA) e implica insatisfacao dos pacientes. Avaliacao do risco para NVPO e instituicao de profilaxia visando ao bem-estar dos pacientes e a reducao de custos tem sido frequentes em publicacoes medicas. Este estudo observacional avaliou a incidencia, fatores de risco e adequacao e efetividade da profilaxia para NVPO na RPA de um hospital-escola terciario. METODO: As informacoes obtidas a partir de prontuarios e questionarios aplicados aos pacientes incluiram idade, fatores preditivos maiores para NVPO (sexo feminino, historia previa, nao-tabagismo, uso pos-operatorio de opioides), profilaxia administrada, ocorrencia de NVPO, tipo de cirurgia e anestesia, utilizacao de oxido nitroso, estado clinico e tempo de permanencia na RPA. RESULTADOS: Observou-se incidencia de 18,5% de nauseas e 8,5% de vomitos no pos-operatorio imediato. Observou-se, ainda, correlacao entre fatores maiores de risco e ocorrencia de NVPO. Nao se observou correlacao entre tais fatores e a utilizacao de medicacao antiemetica profilatica, bem como entre sua utilizacao e a ocorrencia de NVPO. Contudo, observou-se tendencia a administracao de medicacao profilatica em pacientes jovens do sexo feminino. CONCLUSOES: A preocupacao dos anestesiologistas da instituicao com NVPO ficou estabelecida. Contudo, a ausencia de correlacao entre risco e profilaxia sugere realizacao empirica e pouco efetiva. Fatores nao-avaliados sao sugeridos pela ausencia de correlacao entre NVPO e o uso de antiemeticos. Orientacao dos anestesiologistas quanto a condutas profilaticas mais eficientes pode aprimorar os cuidados a populacao atendida.

Incidence and prophylaxis of nausea and vomiting in post-anesthetic recovery in a tertiary teaching hospital

JUSTIFICATIVA E OBJETIVOS: Nauseas e vomitos pos-operatorios (NVPO) constituem complicacao frequente e potencialmente grave que aumenta o tempo de recuperacao pos-anestesica (RPA) e implica insatisfacao dos pacientes. Avaliacao do risco para NVPO e instituicao de profilaxia visando ao bem-estar dos pacientes e a reducao de custos tem sido frequentes em publicacoes medicas. Este estudo observacional avaliou a incidencia, fatores de risco e adequacao e efetividade da profilaxia para NVPO na RPA de um hospital-escola terciario. METODO: As informacoes obtidas a partir de prontuarios e questionarios aplicados aos pacientes incluiram idade, fatores preditivos maiores para NVPO (sexo feminino, historia previa, nao-tabagismo, uso pos-operatorio de opioides), profilaxia administrada, ocorrencia de NVPO, tipo de cirurgia e anestesia, utilizacao de oxido nitroso, estado clinico e tempo de permanencia na RPA. RESULTADOS: Observou-se incidencia de 18,5% de nauseas e 8,5% de vomitos no pos-operatorio imediato. Observou-se, ainda, correlacao entre fatores maiores de risco e ocorrencia de NVPO. Nao se observou correlacao entre tais fatores e a utilizacao de medicacao antiemetica profilatica, bem como entre sua utilizacao e a ocorrencia de NVPO. Contudo, observou-se tendencia a administracao de medicacao profilatica em pacientes jovens do sexo feminino. CONCLUSOES: A preocupacao dos anestesiologistas da instituicao com NVPO ficou estabelecida. Contudo, a ausencia de correlacao entre risco e profilaxia sugere realizacao empirica e pouco efetiva. Fatores nao-avaliados sao sugeridos pela ausencia de correlacao entre NVPO e o uso de antiemeticos. Orientacao dos anestesiologistas quanto a condutas profilaticas mais eficientes pode aprimorar os cuidados a populacao atendida.