Eubrando Silvestre Oliveira

Blockade of the action of nitric oxide in human septic shock increases systemic vascular resistance and has detrimental effects on pulmonary function after a short infusion of methylene blue

To investigate the role of nitric oxide in human sepsis, ten patients with severe septic shock requiring vasoactive drug therapy and mechanical ventilation were enrolled in a prospective, open, non-randomized clinical trial to study the acute effects of methylene blue, an inhibitor of guanylate cyclase. Hemodynamic and metabolic variables were measured before and 20, 40, 60, and 120 min after the start of a 1-h intravenous infusion of 4 mg/kg of methylene blue. Methylene blue administration caused a progressive increase in mean arterial pressure (60 [55-70] to 70 [65-100] mmHg, median [25-75th percentiles]; P<0.05), systemic vascular resistance index (649 [479-1084] to 1066 [585-1356] dyne s-1 cm-5 m-2; P<0.05) and the left ventricular stroke work index (35 [27-47] to 38 [32-56] g m-1 m-2; P<0.05) from baseline to 60 min. The pulmonary vascular resistance index increased from 150 [83-207] to 186 [121-367] dyne s-1 cm-5 m-2 after 20 min (P<0.05). Mixed venous saturation decreased from 65 [56-76] to 63 [55-69]% (P<0.05) after 60 min. The PaO2/FiO2 ratio decreased from 168 [131-215] to 132 [109-156] mmHg (P<0.05) after 40 min. Arterial lactate concentration decreased from 5.1 +/- 2.9 to 4.5 +/- 2.1 mmol/l, mean +/- SD (P<0.05) after 60 min. Heart rate, cardiac filling pressures, cardiac output, oxygen delivery and consumption did not change. Methylene blue administration was safe and no adverse effect was observed. In severe human septic shock, a short infusion of methylene blue increases systemic vascular resistance and may improve myocardial function. Although there was a reduction in blood lactate concentration, this was not explained by an improvement in tissue oxygenation, since overall oxygen availability did not change. However, there was a significant increase in pulmonary vascular tone and a deterioration in gas exchange. Further studies are needed to demonstrate if nitric oxide blockade with methylene blue can be safe for patients with septic shock and, particularly, if it has an effect on pulmonary function.

Impacto de um protocolo de desmame de ventilação mecânica na taxa de falha de extubação em pacientes de difícil desmame

OBJECTIVE: To determine whether the predictive accuracy of clinical judgment alone can be improved by supplementing it with an objective weaning protocol as a decision support tool. METHODS: This was a multicenter prospective cohort study carried out at three medical/surgical ICUs. The study involved all consecutive difficult-to-wean ICU patients (failure in the first spontaneous breathing trial [SBT]), on mechanical ventilation (MV) for more than 48 h, admitted between January of 2002 and December of 2005. The patients in the protocol group (PG) were extubated after a T-piece weaning trial and were compared with patients who were otherwise extubated (non-protocol group, NPG). The primary outcome measure was reintubation within 48 h after extubation. RESULTS: We included 731 patients-533 (72.9%) and 198 (27.1%) in the PG and NPG, respectively. The overall reintubation rate was 17.9%. The extubation success rates in the PG and NPG were 86.7% and 69.6%, respectively (p < 0.001). There were no significant differences between the groups in terms of age, gender, severity score, or pre-inclusion time on MV. However, COPD was more common in the NPG than in the PG (44.4% vs. 17.6%; p < 0.001), whereas sepsis and being a post-operative patient were more common in the PG (23.8% vs. 11.6% and 42.4% vs. 26.4%, respectively; p < 0.001 for both). The time on MV after the failure in the first SBT was higher in the PG than in the NPG (9 ± 5 days vs. 7 ± 2 days; p < 0.001). CONCLUSIONS: In this sample of difficult-to-wean patients, the use of a weaning protocol improved the decision-making process, decreasing the possibility of extubation failure.

The reality of patients requiring prolonged mechanical ventilation: a multicenter study

Objetivo: Na ultima decada ocorreu um aumento no numero de pacientes que necessitam manutencao de venti- lacao mecânica prolongada, resultando no surgimento de uma grande popula- cao de pacientes cronicos criticamen- te enfermos. Este estudo estabeleceu a incidencia de ventilacao mecânica pro- longada em quatro unidades de terapia intensiva e relatou as diferentes caracte- risticas, desfechos hospitalares e impacto nos custos e servicos de pacientes com ventilacao mecânica prolongada (depen- dencia de ventilacao mecânica por 21 dias ou mais) em comparacao a pacien- tes sem ventilacao mecânica prolongada (dependencia de ventilacao mecânica in- ferior a 21 dias).Objective The number of patients who require prolonged mechanical ventilation increased during the last decade, which generated a large population of chronically ill patients. This study established the incidence of prolonged mechanical ventilation in four intensive care units and reported different characteristics, hospital outcomes, and the impact of costs and services of prolonged mechanical ventilation patients (mechanical ventilation dependency ≥ 21 days) compared with non-prolonged mechanical ventilation patients (mechanical ventilation dependency < 21 days). Methods This study was a multicenter cohort study of all patients who were admitted to four intensive care units. The main outcome measures were length of stay in the intensive care unit, hospital, complications during intensive care unit stay, and intensive care unit and hospital mortality. Results There were 5,287 admissions to the intensive care units during study period. Some of these patients (41.5%) needed ventilatory support (n = 2,197), and 218 of the patients met criteria for prolonged mechanical ventilation (9.9%). Some complications developed during intensive care unit stay, such as muscle weakness, pressure ulcers, bacterial nosocomial sepsis, candidemia, pulmonary embolism, and hyperactive delirium, were associated with a significantly higher risk of prolonged mechanical ventilation. Prolonged mechanical ventilation patients had a significant increase in intensive care unit mortality (absolute difference = 14.2%, p < 0.001) and hospital mortality (absolute difference = 19.1%, p < 0.001). The prolonged mechanical ventilation group spent more days in the hospital after intensive care unit discharge (26.9 ± 29.3 versus 10.3 ± 20.4 days, p < 0.001) with higher costs. Conclusion The classification of chronically critically ill patients according to the definition of prolonged mechanical ventilation adopted by our study (mechanical ventilation dependency ≥ 21 days) identified patients with a high risk for complications during intensive care unit stay, longer intensive care unit and hospital stays, high death rates, and higher costs.

A adequada comunicação entre os profissionais médicos reduz a mortalidade no centro de tratamento intensivo

OBJETIVOS: A falha de comunicacao entre os profissionais de saude em centros de tratamento intensivo pode estar relacionada ao aumento de mortalidade dos pacientes criticamente doentes. Este estudo teve como objetivo avaliar se falhas de comunicacao entre os medicos assistentes e os medicos rotineiros do centro de tratamento intensivo teriam impacto na morbidade e mortalidade dos pacientes criticos. METODOS: Estudo de coorte incluindo pacientes nao consecutivos admitidos no centro de tratamento intensivo durante 18 meses. Os pacientes foram divididos em 3 grupos conforme o habito de comunicacao de seus medicos assistentes com os medicos rotineiros: CD - comunicacao diaria da conduta (>75% dos dias); CE - comunicacao eventual (25 a 75% dos dias); RC - rara comunicacao (<25% dos dias). Foram coletados dados demograficos, escores de gravidade, motivo de internacao no centro de tratamento intensivo, tempo de internacao no centro de tratamento intensivo e intervencoes realizadas nos pacientes. Foram analisadas as consequencias da falha na comunicacao entre os profissionais medicos (atraso na realizacao de procedimentos, na realizacao de exames diagnosticos, no inicio de antibioticoterapia, no desmame do suporte ventilatorio e no uso de vasopressores) e inadequacoes de prescricao medica (ausencia de cabeceira elevada, ausencia de profilaxia medicamentosa para ulcera de estresse e para trombose venosa profunda) relacionando-as com o desfecho dos pacientes. RESULTADOS: Foram incluidos 792 pacientes no estudo, sendo agrupados da seguinte maneira: CD (n =529), CE (n =187) e RC (n =76). A mortalidade foi maior nos pacientes pertencentes ao grupo RC (26,3%) comparada aos demais (CD =13,6% e CE =17,1%; p <0,05). A analise multivariada demonstrou que o atraso no inicio de antibioticos [RR 1,83 (IC95%: 1,36 - 2,25)], o atraso no inicio do desmame ventilatorio [RR 1,63 (IC95%: 1,25 - 2,04)] e a nao prescricao de profilaxia para trombose venosa profunda [RR 1,98 (IC95%: 1,43 - 3,12)] contribuiram de forma independente para o aumento de mortalidade dos pacientes. CONCLUSAO: A falta de comunicacao entre medicos assistentes e rotineiros do centro de tratamento intensivo pode aumentar a mortalidade dos pacientes, principalmente devido ao atraso no inicio de antibioticos e no desmame da ventilacao mecânica e a nao prescricao de profilaxia para trombose venosa profunda.

Safety of a training program for ultrasound-guided internal jugular vein catheterization in critically ill patients*

OBJECTIVES Evaluate the safety and effectiveness of a training program for performing ultrasound-guided internal jugular vein cannulation in critically ill patients. METHODS Cohort prospective study, evaluating adult patients admitted in a teaching intensive care unit (ICU). Catheter placement was performed by an ICU medical resident. The patients baseline characteristics, vessels position and operator experience were the evaluated variables. The main outcomes were cannulation success rate and incidence of major complications. RESULTS A total of 118 consecutive patients were enrolled between May 2008 and November 2009. The success rate of ultrasound guided catheter placement was 90% (106/118), 77% in the first attempt. Major complications occurred in 4% of the cases (n = 5) and were not associated with the analyzed variables. Inability to place the guide wire was the reason for 58% (7/12) of the failures. Operators with more than 15 previous ultrasound guided cannulations had an increased success rate (95% vs. 79%, p = 0.01) and increased failure was related to previous catheterization (26% vs. 7%, p = 0.02). CONCLUSION Learning ultrasound guidance for IJV vein cannulation was safe and feasible in ICU patients. This process was not associated to complications and better results were achieved across the spectrum of operator experience.

Mechanical ventilation weaning protocol improves medical adherence and results

Introduction: Implementation of a weaning protocol is related to better patient prognosis. However, new approaches may take several years to become the standard of care in daily practice. We conducted a prospective cohort study to investigate the effectiveness of a multifaceted strategy to implement a protocol to wean patients from mechanical ventilation (MV) and to evaluate the weaning success rate as well as practitioner adherence to the protocol. Methods: We investigated all consecutive MV‐dependent subjects admitted to a medical‐surgical intensive care unit (ICU) for > 24 h over 7 years. The multifaceted strategy consisted of continuing education of attending physicians and ICU staff and regular feedback regarding patient outcomes. The study was conducted in three phases: protocol development, protocol and multifaceted strategy implementation, and protocol monitoring. Data regarding weaning outcomes and physician adherence to the weaning protocol were collected during all phases. Results: We enrolled 2469 subjects over 7 years, with 1,943 subjects (78.7%) experiencing weaning success. Physician adherence to the protocol increased during the years of protocol and multifaceted strategy implementation (from 38% to 86%, p < 0.01) and decreased in the protocol monitoring phase (from 73.9% to 50.0%, p < 0.01). However, during the study years, the weaning success of all subjects increased (from 73.1% to 85.4%, p < 0.001). When the weaning protocol was evaluated step‐by‐step, we found high adherence for noninvasive ventilation use (95%) and weaning predictor measurement (91%) and lower adherence for control of fluid balance (57%) and daily interruption of sedation (24%). Weaning success was higher in patients who had undergone the weaning protocol compared to those who had undergone weaning based in clinical practice (85.6% vs. 67.7%, p < 0.001). Conclusions: A multifaceted strategy consisting of continuing education and regular feedback can increase physician adherence to a weaning protocol for mechanical ventilation. HIGHLIGHTSA multifaceted strategy consisting of continuing education and regular feedback can increase physician adherence to a weaning protocol for mechanical ventilation.There was good medical acceptance of the implementation of the protocol for some factors, including multidisciplinary guidance and education of the ICU staff; additionally, a weaning program was developed that included leadership, education, and supervision.

The Reality of Patients Requiring Prolonged Mechanical Ventilation: A Retrospective Multicenter Cohort Study

Context: The number of patients requiring prolonged mechanical ventilation (PMV) has increased over the last decade, generating a large population of chronically ill patients. Objective: To establish the incidence of PMV in four Intensive Care Units (ICUs), and to report different characteristics, hospital outcomes, and the impact of costs and services of PMV patients (mechanical ventilation dependency = 21 days) compared with non-PMV patients (mechanical ventilation dependency < 21 days). Design, Setting, and Patients: A retrospective multicenter cohort study, including all patients admitted to four ICUs. Main Outcome Measures: Length of stay in the ICU, hospital, complications during ICU stay, and ICU and hospital mortality. Results: During study period, there were 5,287 admission episodes to the ICUs. Forty-one point five percent of these patients needed ventilatory support (n=2,197), and 218 met criteria for PMV (9.9%). Some complications developed during ICU stay, such as muscle weakness, pressure ulcers, bacterial nosocomial sepsis, candidemia, pulmonary embolism, and hyperactive delirium, were associated with a significantly higher risk of PMV. PMV patients had a significant increase in ICU mortality (absolute difference=14.2%, p<0.001), and in hospital mortality (absolute difference=19.1%, p<0.001); PMV group spent more days in the hospital after ICU discharge (26.9 ± 29.3 vs. 10.3 ± 20.4, p<0.001) and with higher costs. Conclusions: the classification of chronically critically ill patients according to the definition of PMV adopted by our study (mechanical ventilation dependency =21 days) identified patients with high risk for complications during ICU stay, high ICU and hospital stay, high death rates, as well as higher costs.