Lung and blood perioperative metalloproteinases in patients undergoing oncologic lung surgery: Prognostic implications.

BACKGROUND: Metalloproteinases (MMPs) have been reported to be related to oncologic outcomes. The main goal of the study was to study the relationship between these proteins and the long-term prognosis of patients undergoing oncologic lung resection surgery. METHODS: This was a substudy of the phase IV randomized control trial (NCT02168751). We analyzed MMP-2, -3, -7, and -9 in blood samples and bronchoalveolar lavage (LBA) and the relationship between MMPs and long postoperative outcomes (survival and disease-free time of oncologic recurrence). RESULTS: Survival was longer in patients who had lower MMP-2 levels than those with higher MMP-2 in blood samples taken 6 h after surgery (6.8 vs. 5.22 years; p = 0.012) and MMP-3 (6.82 vs. 5.35 years; p = 0.03). In contrast, survival was longer when MMP-3 levels were higher in LBA from oncologic lung patients than those with lower MMP-3 (7.96 vs. 6.02 years; p = 0.005). Recurrence-free time was longer in patients who had lower MMP-3 levels in blood samples versus higher (5.97 vs. 4.23 years; p = 0.034) as well as lower MMP-7 (5.96 vs. 4.5 years; p = 0.041) or lower MMP-9 in LBA samples (6.21 vs. 4.18 years; p = 0.012). CONCLUSION: MMPs were monitored during the perioperative period of oncologic lung resection surgery. These biomarkers were associated with mortality and recurrence-free time. The role of the different MMPs analyzed during the study do not have the same prognostic implications after this kind of surgery.

Influence of postoperative complications on long-term outcome after oncologic lung resection surgery. Substudy of a randomized control trial.

Lung resection surgery (LRS) causes an intense local and systemic inflammatory response. There is a relationship between inflammation and postoperative complications (POCs). Also, it has been proposed that the inflammation and complications related with the surgery may promote the recurrence of cancer and therefore deterioration of survival. We investigated the association between inflammatory biomarkers, severity of POCs and long-term outcome in patients who were discharged after LRS. This is a prospective substudy of a randomized control trial. We established three groups based in the presence of POCs evaluated by Clavien-Dindo (C-D) classification: Patients with no postoperative complications (No-POCs group) (C-D = 0), patients who developed light POCs (L-POCs group) (C-D = I-II), and major POCs (M-POCs group) (C-D = III, IV, or V). Kaplan-Meier curves and Cox regression model were created to compare survival and oncologic recurrence in those groups. Patients who developed POCs (light or major) had an increase in some inflammatory biomarkers (TNF-α, IL-6, IL-7, IL-8) compared with No-POCs group. This pro-inflammatory status plays a fundamental role in the appearance of POCs and therefore in a shorter life expectancy. Individuals in the M-POCs group had a higher risk of death (HR = 3.59, 95% CI 1.69 to 7.63) compared to individuals in the No-POCs group (p = 0.001). Patients of L-POCs group showed better survival than M-POCs group (HR = 2.16, 95% CI 1.00 to 4.65, p = 0.049). Besides, M-POCs patients had higher risk of recurrence in the first 2 years, when compared with L-POCs (p = 0,008) or with No-POCs (p = 0.002). In patients who are discharged after undergoing oncologic LRS, there is an association between POCs occurrence and long term outcome. Oncologist should pay special attention in patients who develop POCs after LRS.

Effect of intraoperative paravertebral or intravenous lidocaine versus control during lung resection surgery on postoperative complications: A randomized controlled trial.

BACKGROUND: Use of minimally invasive surgical techniques for lung resection surgery (LRS), such as video-assisted thoracoscopy (VATS), has increased in recent years. However, there is little information about the best anesthetic technique in this context. This surgical approach is associated with a lower intensity of postoperative pain, and its use has been proposed in programs for enhanced recovery after surgery (ERAS). This study compares the severity of postoperative complications in patients undergoing LRS who have received lidocaine intraoperatively either intravenously or via paravertebral administration versus saline. METHODS/DESIGN: We will conduct a single-center randomized controlled trial involving 153 patients undergoing LRS through a thoracoscopic approach. The patients will be randomly assigned to one of the following study groups: intravenous lidocaine with more paravertebral thoracic (PVT) saline, PVT lidocaine with more intravenous saline, or intravenous remifentanil with more PVT saline. The primary outcome will be the comparison of the postoperative course through Clavien-Dindo classification. Furthermore, we will compare the perioperative pulmonary and systemic inflammatory response by monitoring biomarkers in the bronchoalveolar lavage fluid and blood, as well as postoperative analgesic consumption between the three groups of patients. We will use an ANOVA to compare quantitative variables and a chi-squared test to compare qualitative variables. DISCUSSION: The development of less invasive surgical techniques means that anesthesiologists must adapt their perioperative management protocols and look for anesthetic techniques that provide good analgesic quality and allow rapid rehabilitation of the patient, as proposed in the ERAS protocols. The administration of a continuous infusion of intravenous lidocaine has proven to be useful and safe for the management of other types of surgery, as demonstrated in colorectal cancer. We want to know whether the continuous administration of lidocaine by a paravertebral route can be substituted with the intravenous administration of this local anesthetic in a safe and effective way while avoiding the risks inherent in the use of regional anesthetic techniques. In this way, this technique could be used in a safe and effective way in ERAS programs for pulmonary resection. TRIAL REGISTRATION: EudraCT, 2016-004271-52; ClinicalTrials.gov, NCT03905837 . Protocol number IGGFGG-2016 version 4.0, 27th April 2017.

Predictive value of plasma cytokines for acute kidney injury following lung resection surgery: prospective observational study / Valor preditivo das citocinas plasmáticas para lesão renal aguda após cirurgia de ressecção pulmonar: estudo observacional prospectivo

Abstract Background and objectives: Patients undergoing lung resection surgery are at risk of developing postoperative acute kidney injury. Determination of cytokine levels allows the detection of an early inflammatory response. We investigated any temporal relationship among perioperative inflammatory status and development of acute kidney injury after lung resection surgery. Furthermore, we evaluated the impact of acute kidney injury on outcome and analyzed the feasibility of cytokines to predict acute kidney injury. Methods: We prospectively analyzed 174 patients scheduled for elective lung resection surgery with intra-operative periods of one-lung ventilation periods. Fiberoptic broncho-alveolar lavage was performed in each lung before and after one-lung ventilation periods for cytokine analysis. As well, cytokine levels were measured from arterial blood samples at five time points. acute kidney injury was diagnosed within 48 h of surgery based on acute kidney injury criteria. We analyzed the association between acute kidney injury and cardiopulmonary complications, length of intensive care unit and hospital stays, intensive care unit re-admission, and short-term and long-term mortality. Results: The incidence of acute kidney injury in our study was 6.9% (12/174). Acute kidney injury patients showed higher plasma cytokine levels after surgery but differences in alveolar cytokines were not detected. Although no patient required renal replacement therapy, acute kidney injury patients had higher incidence of cardiopulmonary complications and increased overall mortality. Plasma interleukin-6 at 6 h was the most predictive cytokine of acute kidney injury (cut-off point at 4.89 pg.mL-1). Conclusions: Increased postoperative plasma cytokine levels are associated with acute kidney injury after lung resection surgery in our study, which worsens the prognosis. Plasma interleukin-6 may be used as an early indicator for patients at risk of developing acute kidney injury after lung resection surgery.

Resumo Justificativa e objetivos: Os pacientes submetidos à cirurgia de ressecção pulmonar apresentam risco de desenvolver lesão renal aguda pós-operatória. A determinação dos níveis de citocinas permite detectar uma resposta inflamatória precoce. Investigamos a relação temporal entre o estado inflamatório perioperatório e o desenvolvimento de lesão renal aguda após cirurgia de ressecção pulmonar. Além disso, avaliamos o impacto da lesão renal aguda no desfecho e analisamos a viabilidade das citocinas para prever este tipo de lesão. Métodos: No total, foram analisados prospectivamente 174 pacientes agendados para cirurgia eletiva de ressecção pulmonar com períodos intraoperatórios de ventilação monopulmonar. Lavado bronco-alveolar com fibra óptica foi realizado em cada pulmão antes e após os períodos de ventilação monopulmonar para análise das citocinas. Os níveis de citocina foram medidos a partir de amostras de sangue arterial em cinco momentos. A lesão renal aguda foi diagnosticada dentro de 48 horas após a cirurgia, com base nos critérios para sua verificação. Analisamos a associação entre lesão renal aguda e complicações cardiopulmonares, tempo de internação em unidade de terapia intensiva e de internação hospitalar, reinternação em unidade de terapia intensiva e mortalidade a curto e longo prazos. Resultados: A incidência de lesão renal aguda no estudo foi de 6,9% (12/174). Os pacientes com lesão renal aguda apresentaram níveis mais altos de citocinas plasmáticas após a cirurgia, mas não foram detectadas diferenças nas citocinas alveolares. Embora nenhum paciente tenha precisado de terapia renal substitutiva, os com lesão renal aguda apresentaram maior incidência de complicações cardiopulmonares e aumento da mortalidade geral. A interleucina-6 plasmática em seis horas foi a citocina mais preditiva de lesão renal aguda (ponto de corte em 4,89 pg.mL-1). Conclusões: O aumento dos níveis plasmáticos de citocinas no pós-operatório está associado à lesão renal aguda após cirurgia de ressecção pulmonar no estudo, o que piora o prognóstico. A interleucina-6 plasmática pode ser usada como um indicador precoce para pacientes com risco de desenvolver lesão renal aguda após cirurgia de ressecção pulmonar.

[Predictive value of plasma cytokines for acute kidney injury following lung resection surgery: prospective observational study]. / Valor preditivo das citocinas plasmáticas para lesão renal aguda após cirurgia de ressecção pulmonar: estudo observacional prospectivo.

BACKGROUND AND OBJECTIVES: Patients undergoing lung resection surgery are at risk of developing postoperative acute kidney injury. Determination of cytokine levels allows the detection of an early inflammatory response. We investigated any temporal relationship among perioperative inflammatory status and development of acute kidney injury after lung resection surgery. Furthermore, we evaluated the impact of acute kidney injury on outcome and analyzed the feasibility of cytokines to predict acute kidney injury. METHODS: We prospectively analyzed 174 patients scheduled for elective lung resection surgery with intra-operative periods of one-lung ventilation. Fiberoptic broncho-alveolar lavage was performed in each lung before and after one-lung ventilation periods for cytokine analysis. As well, cytokine levels were measured from arterial blood samples at five time points. Acute kidney injury was diagnosed within 48h of surgery based estabilished criteria for its diagnosis. We analyzed the association between acute kidney injury and cardiopulmonary complications, length of intensive care unit and hospital stays, intensive care unit re-admission, and short-term and long-term mortality. RESULTS: The incidence of acute kidney injury in our study was 6.9% (12/174). Acute kidney injury patients showed higher plasma cytokine levels after surgery, but differences in alveolar cytokines were not detected. Although no patient required renal replacement therapy, acute kidney injury patients had higher incidence of cardiopulmonary complications and increased overall mortality. Plasma interleukin-6 at 6h was the most predictive cytokine of acute kidney injury (cut-off point at 4.89pg.mL-1). CONCLUSIONS: Increased postoperative plasma cytokine levels are associated with acute kidney injury after lung resection surgery in our study, which worsens the prognosis. Plasma interleukin-6 may be used as an early indicator for patients at risk of developing acute kidney injury after lung resection surgery.

Usefulness of combining clinical and biochemical parameters for prediction of postoperative pulmonary complications after lung resection surgery.

Early detection of patients with a high risk of postoperative pulmonary complications (PPCs) could improve postoperative strategies. We investigated the role of monitoring systemic and lung inflammatory biomarkers during surgery and the early postoperative period to detect patients at high risk of PPCs after lung resection surgery (LRS). This is a substudy of a randomized control trial on the inflammatory effects of anaesthetic drugs during LRS. We classified patients into two groups, depending on whether or not they developed PPCs. We constructed three multivariate logistic regression models to analyse the power of the biomarkers to predict PPCs. Model 1 only included the usual clinical variables; Model 2 included lung and systemic inflammatory biomarkers; and Model 3 combined Models 1 and 2. Comparisons between mathematical models were based on the area under the receiver operating characteristic curve (AUROC) and tests of integrated discrimination improvement (IDI). Statistical significance was set at p < 0.05. PPCs were detected in 37 (21.3%) patients during admission. The AUROC for Models 1, 2, and 3 was 0.79 (95% CI 0.71-0.87), 0.80 (95% CI 0.72-0.88), and 0.93 (95% CI 0.88-0.97), respectively. Comparison of the AUROC between Models 1 and 2 did not reveal statistically significant values (p = 0.79). However, Model 3 was superior to Model 1 (p < 0.001). Model 3 had had an IDI of 0.29 (p < 0.001) and a net reclassification index of 0.28 (p = 0.007). A mathematical model combining inflammation biomarkers with clinical variables predicts PPCs after LRS better than a model that includes only clinical data. Clinical registration number Clinical Trial Registration NCT02168751; EudraCT 2011-002294-29.

Behavior of stroke volume variation in hemodynamic stable patients during thoracic surgery with one-lung ventilation periods / Comportamento da variação do volume sistólico em pacientes hemodinamicamente estáveis durante cirurgia torácica com períodos de ventilação monopulmonar

Abstract Introduction: In last few years, emphasis was placed in goal-directed therapy in order to optimize patient's hemodynamic status and improve their prognosis. Parameters based on the interaction between heart and lungs have been questioned in situations like low tidal volume and open chest surgery. The goal of the study was to analyze the changes that one-lung ventilation can produce over stroke volume variation and to assess the possible impact of airway pressures and lung compliance over stroke volume variation. Methods: Prospective observational study, 112 patients undergoing lung resection surgery with one-lung ventilation periods were included. Intravenous fluid therapy with crystalloids was set at 2 mL.g-1. Hypotension episodes were treated with vasoconstrictive drugs. Two-lung Ventilation was implemented with a TV of 8 mL.g-1 and one-lung ventilation was managed with a TV of 6 mL.g-1. Invasive blood pressure was monitored. We recorded the following cardiorespiratory values: heart rate, mean arterial pressure, cardiac index, stroke volume index, airway peak pressure, airway plateau pressure and static lung compliance at 3 different times during surgery: immediately after lung collapse, 30 min after initiating one-lung ventilation and after restoration of two-lung ventilation. Results: Stroke volume variation values were influenced by lung collapse (before lung collapse 14.6 (DS) vs. OLV 9.9% (DS), p < 0.0001); or after restoring two-lung ventilation (11.01 (DS), p < 0.0001). During two-lung Ventilation there was a significant correlation between airway pressures and stroke volume variation, however this correlation lacks during one-lung ventilation. Conclusion: The decrease of stroke volume variation values during one-lung ventilation with protective ventilatory strategies advices not to use the same threshold values to determine fluid responsiveness.

Resumo Introdução: Nos últimos anos, a importância da terapia alvo-dirigida foi enfatizada para aprimorar o estado hemodinâmico do paciente e melhorar seu prognóstico. Os parâmetros baseados na interação entre o coração e os pulmões foram questionados em situações como baixo volume corrente e cirurgia aberta do tórax. O objetivo do estudo foi analisar as alterações que a ventilação monopulmonar pode produzir na variação do volume sistólico e avaliar o possível impacto das pressões da via aérea e da complacência pulmonar sobre a variação do volume sistólico. Métodos: Estudo observacional prospectivo, no qual 112 pacientes submetidos à cirurgia de ressecção pulmonar com períodos de ventilação monopulmonar foram incluídos. A terapia de fluídos intravenosos com cristaloides foi ajustada a 2 mL.kg-1.h-1. Os episódios de hipotensão foram tratados com vasoconstritores. A ventilação dos dois pulmões (VDP) foi implantada com volume corrente de 8 mL.kg-1 e a ventilação monopulmonar foi controlada com volume corrente de 6 mL.kg-1. Foi monitorada a pressão arterial invasiva. Registramos os seguintes valores cardiorrespiratórios: frequência cardíaca, pressão arterial média, índice cardíaco, índice de volume sistólico, pressão de pico das vias aéreas, pressão de platô das vias aéreas e complacência pulmonar estática em três tempos durante a cirurgia: imediatamente após o colapso do pulmão, 30 minutos após o início da ventilação monopulmonar e após a restauração da ventilação dos dois pulmões. Resultados: Os valores de variação do volume sistólico foram influenciados pelo colapso pulmonar (antes do colapso pulmonar 14,6 [DS] vs. ventilação monopulmonar 9,9% [DS], p < 0,0001), ou após o restabelecimento da ventilação dos dois pulmões (11,01 [DS], p < 0,0001). Durante a ventilação dos dois pulmões houve uma correlação significativa entre as pressões das vias aéreas e a variação do volume sistólico, porém, essa correlação não existe durante a ventilação monopulmonar. Conclusão: A diminuição dos valores da variação do volume sistólico durante a ventilação monopulmonar com estratégias ventilatórias protetoras sugere não usar os mesmos valores de limiar para determinar a responsividade aos fluídos.

[Behaviour of stroke volume variation in hemodynamic stable patients during thoracic surgery with one-lung ventilation periods]. / Comportamento da variação do volume sistólico em pacientes hemodinamicamente estáveis durante cirurgia torácica com períodos de ventilação monopulmonar.

INTRODUCTION: In last few years, emphasis was placed in goal-directed therapy in order to optimize patient's hemodynamic status and improve their prognosis. Parameters based on the interaction between heart and lungs have been questioned in situations like low tidal volume and open chest surgery. The goal of the study was to analyze the changes that one-lung ventilation can produce over stroke volume variation and to assess the possible impact of airway pressures and lung compliance over stroke volume variation. METHODS: Prospective observational study, 112 patients undergoing lung resection surgery with one-lung ventilation periods were included. Intravenous fluid therapy with crystalloids was set at 2mL.kg-1.h-1. Hypotension episodes were treated with vasoconstrictive drugs. Two-lung ventilation was implemented with a TV of 8mL.kg-1 and one-lung ventilation was managed with a TV of 6mL.kg-1. Invasive blood pressure was monitored. We recorded the following cardiorespiratory values: heart rate, mean arterial pressure, cardiac index, stroke volume index, airway peak pressure, airway plateau pressure and static lung compliance at 3 different times during surgery: immediately after lung collapse, 30minutes after initiating one-lung ventilation and after restoration of two-lung ventilation. RESULTS: Stroke volume variation values were influenced by lung collapse (before lung collapse14.6 (DS) vs. OLV 9.9% (DS), p < 0.0001); or after restoring two-lung ventilation (11.01 (DS), p < 0.0001). During two-lung ventilation there was a significant correlation between airwaypressures and stroke volume variation, however this correlation lacks during one-lung ventilation. CONCLUSION: The decrease of stroke volume variation values during one-lung ventilation with protective ventilatory strategies advices not to use the same threshold values to determine fluid responsiveness.

[Deep versus moderate neuromuscular block during one-lung ventilation in lung resection surgery]. / Bloqueio neuromuscular profundo versus moderado durante a ventilação monopulmonar em cirurgia de ressecção pulmonar.

BACKGROUND AND OBJECTIVES: Neuromuscular relaxants are essential during general anesthesia for several procedures. Classical anesthesiology literature indicates that the use of neuromuscular blockade in thoracic surgery may be deleterious in patients in lateral decubitus position in one-lung ventilation. The primary objective of our study was to compare respiratory function according to the degree of patient neuromuscular relaxation. Secondary, we wanted to check that neuromuscular blockade during one-lung ventilation is not deleterious. METHODS: A prospective, longitudinal observational study was made in which each patient served as both treated subject and control. 76 consecutive patients programmed for lung resection surgery in Gregorio Marañon Hospital along the year of 2013 who required one-lung ventilation in lateral decubitus were included. Ventilator data, hemodynamic parameters were registered in different moments according to train-of-four response (intense, deep and moderate blockade) during one-lung ventilation. RESULTS: Peak, plateau and mean pressures were significantly lower during the intense and deep blockade. Besides, compliance and peripheral oxygen saturation were significantly higher in those moments. Heart rate was significantly higher during deep blockade. No mechanical ventilation parameters were modified during measurements. CONCLUSIONS: Deep neuromuscular blockade attenuates the poor lung mechanics observed during one-lung ventilation.

Systemic and alveolar inflammatory response in the dependent and nondependent lung in patients undergoing lung resection surgery: A prospective observational study.

BACKGROUND: Measurement of inflammatory mediators in bronchoalveolar lavage (BAL) during lung resection surgery with periods of one-lung ventilation (OLV) has revealed an intense local pulmonary response. The role of each lung in the inflammation that occurs during this procedure has never been investigated. OBJECTIVE(S): The primary objective of our study was to compare the inflammatory response in the dependent lung with that of the nondependent lung by measuring inflammatory markers in BAL. Our secondary objective was to assess the behaviour of these inflammatory mediators in patients with and without postoperative pulmonary complications (PPCs). DESIGN: A prospective, observational study. SETTING: Department of Anaesthesiology in a university hospital. PATIENTS: Forty-six consecutive patients undergoing lung resection surgery. INTERVENTION(S): BAL samples were taken from dependent and nondependent lung 10 min before initiating OLV and at the end of OLV (once two-lung ventilation was established). All patients were followed up until 30 days after surgery. MAIN OUTCOME MEASURES: The concentration of cytokines [interleukin (IL)-1, IL-2, IL-6, IL-10, tumour necrosis factor-alpha (TNF-α)], nitric oxide, carbon monoxide and matrix metalloproteinase 2 (MMP-2) was analysed in both lungs before and after OLV. PPCs were recorded. RESULTS: In BAL fluid, all measured biomarkers, apart from IL-10, were significantly greater (P < 0.05) at the end of OLV than those obtained before OLV, both for the dependent and nondependent lung. The increase in measured biomarkers was similar in both lungs. Eight patients developed PPC. Patients who developed PPC had higher levels of TNF-α (P < 0.05) in BAL from the nondependent lung before and after OLV than patients who did not have PPC. Patients who developed PPC had a smaller increase in MMP-2 levels (P < 0.05) in the dependent lung than patients who did not have PPC. CONCLUSION: In lung resection surgery, the inflammatory response is similar in both lungs. However, the greater increase in TNF-α levels in the nondependent lung and the smaller increase of MMP-2 concentration in the dependent lung may increase the susceptibility to develop PPC.

Effects of ventilatory mode during one-lung ventilation on intraoperative and postoperative arterial oxygenation in thoracic surgery.

OBJECTIVE: The purpose of this study was to investigate the relationship between the ventilatory mode used during one-lung ventilation (OLV) and intraoperative and early postoperative arterial oxygenation in patients undergoing thoracic surgery. METHODS: A prospective, randomized clinical trial. SETTING: A tertiary care university hospital single institution. PARTICIPANTS: One hundred ten patients scheduled for thoracic surgery with at least 1 hour of OLV. INTERVENTIONS: Patients were prospectively randomized into 2 groups depending on the ventilatory mode used during OLV: volume-controlled ventilation (VCV) or pressure-controlled ventilation (PCV). In VCV, the authors used a tidal volume (Vt) of 8 mL/kg and in the PCV group an inspiratory pressure to provide a tidal volume of 8 mL/kg. MEASUREMENTS AND MAIN RESULTS: Airway pressures and arterial blood gases were obtained at 20, 30, and 40 minutes after OLV. The authors recorded the ratio of arterial oxygen tension to inspired oxygen fraction (PaO(2)/F(I)O(2)) at 4 hours (RU1) and 24 hours (RU2) after surgery. During OLV, there were no differences in arterial oxygenation, airway plateau pressure, and mean pressure between groups, although peak pressure was higher in the VCV group (p < 0.01). The PaO(2)/F(I)O(2) ratio at RU1 was 312.6 +/- 106 in the VCV group and 322.1 +/- 104. In the PCV group at RU2, it was 402.4 +/- 105 and 389.6 +/- 114, respectively, and there were no significant differences between the groups. CONCLUSIONS: In patients undergoing thoracic surgery, the use of PCV compared with VCV during OLV with the same Vt of 8 mL/kg does not affect arterial oxygenation during OLV or early postoperative oxygenation.

The impact of lung recruitment on hemodynamics during one-lung ventilation.

OBJECTIVE: The objective of the present study was to investigate respiratory and hemodynamic changes by measuring continuous cardiac output, cardiac filling, and stroke volume variation after lung recruitment in thoracic surgery. DESIGN: A prospective, observational study. SETTING: A tertiary care university hospital single institution. PARTICIPANTS: Forty patients undergoing thoracotomy for lung resection with at least 1 hour of one-lung ventilation (OLV). INTERVENTIONS: During OLV, an alveolar recruitment maneuver (ARM) was performed. MEASUREMENTS AND MAIN RESULTS: Based on Edwards Vigileo/FloTrac system (Edwards Lifesciences, Irvine, CA), the arterial pressure-based cardiac output, cardiac index, systemic vascular resistance, stroke volume variation, and central venous oxygen saturation were recorded immediately before the maneuver and 1, 2, 3, 4, 5, and 10 minutes after the maneuver. Stroke volume variation was the parameter most affected during and after the maneuver; it increased to 50% and 40% in the first and second minute, respectively (p < 0.01). The cardiac index was also affected and decreased 9.4% (p < 0.05) in the first minute after the maneuver. ScvO2 decreased significantly during the first 2 minutes (7% and 6.5%, respectively). However, after 3 minutes, all values recorded were similar to prerecruitment values. The PaO2 and PcvO2 from samples taken 10 minutes after the maneuver improved considerably with respect to the values before alveolar recruitment. CONCLUSIONS: The authors concluded that during open-chest surgery with OLV, an ARM effectively improved oxygenation without inducing important circulatory changes.

Comparison of the hemodynamic effects of a single 5 mg/kg dose of lidocaine with or without epinephrine for thoracic paravertebral block.

BACKGROUND AND OBJECTIVES: Epinephrine is often added to local anesthetic solutions to minimize and slow the systemic absorption of local anesthetics, and thus reduce the possibility of adverse effects of these drugs. In an earlier study we found that the injection of 5 mg/kg of lidocaine via the paravertebral route depressed myocardial contractility by up to 30%, with practically no changes in heart rate or blood pressure. In the present study we investigated whether these alterations are due to systemic absorption of the local anesthetic, and whether such absorption can be minimized by adding epinephrine to the local anesthetic solution. METHODS: A prospective, blind, and randomized study was made of 50 patients subjected to lung resection surgery. The subjects were divided into two groups: Lid group (5 mg/kg bolus dose of lidocaine in the thoracic paravertebral space) and Lid+E group (addition of 5 mcg/mL of epinephrine to the local anesthetic). The anesthetic solution was administered through a paravertebral catheter ipsilateral to the operative side. In addition to routine hemodynamic monitoring (heart rate and radial artery blood pressure), an aortic transpulmonary thermodilution catheter was inserted into the femoral artery for recording of the following variables: cardiac index, cardiac function index, maximum pressure derivative, global end diastolic volume, and intrathoracic total blood volume index. Data collection was carried out immediately before administration of the anesthetic solution and 15, 30, and 45 minutes after administration. Measurements were made of the plasma lidocaine levels at those same postparavertebral injection time points. RESULTS: Prior to paravertebral dosing there were no differences in terms of the hemodynamic variables studied. However, 15 minutes after dosing in the Lid+E group, lesser reductions in contractility, cardiac function index, and cardiac index were recorded, compared with the Lid group, with a significant reduction in cardiac filling volumes. Blood lidocaine levels were 53% and 34% lower in Lid+E group, as recorded 15 and 30 minutes after injection. The patients who, 15 minutes after paravertebral injection, had blood lidocaine levels greater than 3 mcg/mL (independently of the type of anesthetic solution used) had a significant reduction in mean blood pressure, cardiac function index, cardiac index, and maximum pressure derivative, compared with the patients with lower blood lidocaine concentrations. CONCLUSIONS: Addition of epinephrine to lidocaine when performing thoracic paravertebral block, attenuates the cardiodepressive effects associated with the systemic absorption of lidocaine and also, as a result of the beta-adrenergic consequences of epinephrine, systemic absorption from the paravertebral space.