Irene Rovira

Worsening of pulmonary gas exchange with nitric oxide inhalation in chronic obstructive pulmonary disease

BACKGROUND Inhalation of nitric oxide (NO) causes selective pulmonary vasodilation and improves arterial oxygenation in acute respiratory distress syndrome. But some patients do not respond or gas exchange worsens when inhaling NO. We hypothesised that this detrimental effect might be related to the reversion of hypoxic vasoconstriction in those patients where this mechanism contributes to ventilation-perfusion (V(A)/Q) matching. METHODS We studied 13 patients with advanced chronic obstructive pulmonary disease (COPD). We compared their responses to breathing room air, NO at 40 parts per million in air, and 100% O2. Changes in pulmonary haemodynamics, blood gases, and V(A)/Q distributions were assessed. FINDINGS NO inhalation decreased the mean (SE) pulmonary artery pressure from 25.9 (2.0) to 21.5 (1.7) mm Hg (p = 0.001) and PaO2 from 56 (2) 53 (2) mm Hg (p = 0.014). The decrease in PaO2 resulted from worsening of V(A)/Q distributions, as shown by a greater dispersion of the blood-flow distribution (logSD Q) from 1.11 (0.1) to 1.22 (0.1) (p = 0.018). O2 breathing reduced the mean pulmonary arterial pressure to 23.4 (2.1) mm Hg and caused greater V(A)/Q mismatch (logSD Q, 1.49 [0.1]). The intrapulmonary shunt on room air was small (2.7 [0.9]%) and did not change when breathing NO or O2. INTERPRETATION We conclude that in patients with COPD, in whom hypoxaemia is caused essentially by V(A)/Q imbalance rather than by shunt, inhaled NO can worsen gas exchange because of impaired hypoxic regulation of the matching between ventilation and perfusion.

Awake upper airway surgery.

BACKGROUND The need to compromise between surgical and anesthetic access in airway surgery is an important clinical problem. We wanted to determine the feasibility of performing upper airway surgery under awake anesthesia and spontaneous respiration. METHODS This was a prospective, clinical feasibility study. Patients with upper tracheal stenosis were managed through cervical epidural anesthesia and conscious sedation, and atomized local anesthetic. No intraoperative intubation or jet ventilation was required. Outcome measures were ease of surgery, observer-rated functional result, early (less than 30 days) complications, and patient-reported satisfaction. RESULTS Twenty consecutive patients with idiopathic (n = 4) or postintubation (n = 16) complete (n = 3) or severe (>80%, n = 17) subglottic (n = 12) or upper trachea (n = 8) stenosis were enrolled. Operations included 12 subglottic and 8 segmental resections with primary anastomosis. Permissive hypercapnia was well tolerated. Median length of resection was 4.5 cm (range, 2 to 6 cm), and 12 releases (8 thyrohyoid, 4 suprahyoid) were required. One patient required a nasotracheal tube for 36 hours. All but 1 were able to cough and talk immediately, and to swallow fluids and solids, and were fully mobilized at 6 hours. There were no early complications. Median hospitalization was 3.1 days (range, 2 to 15). Patients had excellent (n = 16) or good (n = 4) functional (n = 20) outcomes, with no early relapse of stenosis. Median self-reported satisfaction at median 12 months was 9.5 +/- 1.0 (scale, 0 to 10). All patients indicated that they would be happy to repeat the procedure. CONCLUSIONS Awake and tubeless upper airway surgery is feasible and safe, and has a high level of patient satisfaction. If supported by randomized controlled trial, this method will change the way airway stenosis surgery is approached by both surgeons and anesthesiologist.

Transoesophageal echocardiography accurately detects cardiac output variation: a prospective comparison with thermodilution in cardiac surgery

Background and objective: Intraoperative Doppler ultrasound can be used to measure cardiac output by transoesophageal echocardiography. Recently, its reliability, when compared to the thermodilution technique, has been questioned. The purpose of this study was to compare intraoperative changes in cardiac output measured by echo‐Doppler and by thermodilution in cardiac surgery. We also assessed the agreement between the techniques. Methods: Fifty cardiac surgical patients (38 male, 12 female, mean age of 63.4 ± 14.3 yr) were prospectively included after approval by the Ethics Committee of the Institution. Cardiac output was assessed by thermodilution, with 10 mL saline at 12°C, and simultaneously and blindly by echo‐Doppler in deep transgastric view with pulsed wave Doppler at the level of the left ventricular outflow tract. Matched thermodilution cardiac output and echo‐Doppler cardiac output measurements were taken three times at the end of expiration, both pre‐ and post‐cardiopulmonary bypass. Results: Echo‐Doppler measurements were obtained in 44 patients (88%). In three patients, Doppler recordings could not be obtained adequately, and three developed left ventricular outflow tract obstruction after bypass. Bland‐Altman analysis revealed a bias of 0.015 L min−1, with narrow limits of agreement (−1.21 to 1.22 L min−1) and 29.1% error. Echo‐Doppler was accurate (92% sensitivity and 71% specificity, P = 0.008 by receiver operating characteristic curves) for detecting more than 10% of change in thermodilution cardiac output. There were no complications related to the study. Conclusions: The agreement between cardiac output by echo‐Doppler and by thermodilution is clinically acceptable and transoesophageal echocardiography is a reliable tool to assess significant cardiac output changes in a population of selected patients.

Tratamiento médico y quirúrgico de la hipertensión pulmonar tromboembólica crónica: experiencia en un único centro

INTRODUCTION Pulmonary endarterectomy (PE) is the treatment of choice for chronic thromboembolic pulmonary hypertension (CTEPH). The aim of this study was to analyze our experience in the medical and surgical management of CTEPH. METHODS We included 80 patients diagnosed with CTEPH between January 2000 and July 2012. Thirty two patients underwent PE and 48 received medical treatment (MT). We analyzed functional class (FC), six-minute walking distance (6MWD) and pulmonary hemodynamics. Mortality in both groups and periods were analyzed. RESULTS Patients who underwent PE were younger, mostly men, and had longer 6MWD. No differences were observed in pulmonary hemodynamics or FC at diagnosis. One year after treatment, all PE patients versus 41% in MT group were at FCI-II. At follow-up, the PE group showed greater increase in 6MWD, and greater reduction in mean pulmonary arterial pressure and pulmonary vascular resistance than the MT group (P<.05). Overall survival in the MT group at 1 and 5years was 83% and 69%, respectively. Conditional survival in patients alive 100days post-PE at 1 and 5years was 95% and 88%, respectively. Surgical mortality in operated patients in the first period (2000-2006) was 31,3%, and 6,3% in the second (2007-2012). CONCLUSIONS PE provides good clinical results, and improves pulmonary hemodynamics in patients who successfully overcome the immediate postoperative period. After a learning period, the current operatory mortality in our center is similar to international standards.

Complicaciones graves de tipo mecánico asociadas al catéter de arteria pulmonar en cirugía cardiovascular y torácica

Resumen Objetivos A pesar de la discusion sobre la utilidad del cateter de arteria pulmonar (CAP) en el manejo del paciente critico, se sigue utilizando frecuentemente y es conveniente tener en cuenta tambien sus posibles complicaciones. El objetivo del estudio es revisar las complicaciones mecanicas graves o potencialmente graves asociadas a CAP ocurridos en nuestro centro en los ultimos 15 anos. Pacientes y metodos Se ha realizado un estudio observacional retrospectivo sobre los pacientes sometidos a cirugia vascular, cardiaca y toracica en los que se coloco un CAP, considerandose las complicaciones graves de origen mecanico. Resultados Se incluyeron 7.540 pacientes, detectandose nueve casos de complicaciones graves entre los que se incluyen cinco rupturas de arteria pulmonar, tres de ellas con resultado de muerte; una perforacion de vena mamaria interna; un nudo; un acodamiento y un atrapamiento del cateter en la sutura quirurgica. Conclusiones Esto supone una incidencia de 0,12%, menor a la publicada. Aunque la frecuencia de estas complicaciones es baja, su aparicion inesperada obliga a estar alerta ante su posible aparicion, con una cuidadosa seleccion de los pacientes en que se emplea el CAP y especial vigilancia de los signos clinicos y radiologicos caracteristicos de complicaciones.

Single double-lumen venous-venous pump-driven extracorporeal lung membrane support.

OBJECTIVE We sought to investigate the safety and feasibility of obtaining total respiratory support during 72 hours using a pump-driven (Levitronix CentriMag; Levitronix LLC, Waltham, Mass) venous-venous extracorporeal lung membrane (Novalung; Novalung GmbH, Hechingen, Germany) attached through a single double-lumen cannula (Novalung) into the femoral or jugular vein in pigs. METHODS Twelve pigs were initially mechanically ventilated for 2 hours (respiratory rate, 20-25 breaths/min; tidal volume, 10-12 mL/kg; fraction of inspired oxygen, 1.0; positive end-expiratory pressure, 5 cm H(2)O). Thereafter, the extracorporeal lung membrane was attached to the right femoral (n = 6, 26F) or jugular (n = 6, 22F) vein by using a single double-lumen cannula placed transcutaneously. Ventilatory settings were then reduced to near-apneic ventilation (respiratory rate, 4 breaths/min; tidal volume, 1-2 mL/kg; fraction of inspired oxygen, 0.21; positive end-expiratory pressure, 10 cm H(2)O), and pump flow was increased hourly until maximal efficacy. Blood gases and hemodynamics were measured hourly, and lung and plasma cytokine levels were measured every 4 hours. RESULTS The devices mean blood flow was 2.16 +/- 0.43 L/min, permitting an oxygen transfer and carbon dioxide removal of 203.6 +/- 54.6 and 590.3 +/- 23.3 mL/min, respectively. Despite static ventilation, all pigs showed optimal respiratory support, with a PaO(2), PaCO(2), and mixed venous oxygen saturation of 226.2 +/- 56.4, 59.7 +/- 8.8, and 85.6 +/- 5.3 mm Hg, respectively. There were no significant inflammatory, cellular, or coagulatory responses; lung cytokine levels remained in the normal range. Route (femoral vs jugular) or size (22F vs 26F) of the cannula did not change hemodynamic or respiratory parameters significantly. CONCLUSIONS This circuit provides total respiratory support over 72 hours without inducing significant hemodynamic, coagulatory, cellular, or inflammatory responses.

Epidemiology, Clinical Features, and Outcome of Infective Endocarditis due to Abiotrophia Species and Granulicatella Species: Report of 76 Cases, 2000–2015

Background Infective endocarditis (IE) caused by Abiotrophia (ABI) and Granulicatella (GRA) species is poorly studied. This work aims to describe and compare the main features of ABI and GRA IE. Methods We performed a retrospective study of 12 IE institutional cases of GRA or ABI and of 64 cases published in the literature (overall, 38 ABI and 38 GRA IE cases). Results ABI/GRA IE represented 1.51% of IE cases in our institution between 2000 and 2015, compared to 0.88% of HACEK (Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, Kingella)-related IE and 16.62% of Viridans group streptococci (VGS) IE. Institutional ABI/GRA IE case characteristics were comparable to that of VGS, but periannular complications were more frequent (P = .008). Congenital heart disease was reported in 4 (10.5%) ABI and in 11 (28.9%) GRA cases (P = .04). Mitral valve was more frequently involved in ABI than in GRA (P < .001). Patient sex, prosthetic IE, aortic involvement, penicillin susceptibility, and surgical treatment were comparable between the genera. New-onset heart failure was the most frequent complication without genera differences (P = .21). Five (13.2%) ABI patients and 2 (5.3%) GRA patients died (P = .23). Factors associated with higher mortality were age (P = .02) and new-onset heart failure (P = .02). The genus (GRA vs ABI) was not associated with higher mortality (P = .23). Conclusions GRA/ABI IE was more prevalent than HACEK IE and approximately one-tenth as prevalent as VGS; periannular complications were more frequent. GRA and ABI genera IE presented similar clinical features and outcomes. Overall mortality was low, and related to age and development of heart failure.

Disfunción cognitiva después de cirugía cardiaca: Saturación cerebral e índice biespectral: estudio longitudinal

: Prospective study in patients undergoing elective cardiac surgery with cardiopulmonary bypass. A comprehensive neuropsychological assessment was applied preoperatively and 3 months after surgery. Postoperative dysfunction was defi ned as a decrease of at least one standard deviation in two or more neuropsychological tests. Cerebral oxygenation and bispectral index were continuously recorded and corrected throughout surgery. Cerebral oxygenation data were analyzed by the mean value and at three thresholds: 50%, 40% and < 25% of the basal value. Bispectral index was analyzed at threshold of 45.

Mechanical Thrombectomy for Acute Ischemic Stroke Secondary to Infective Endocarditis

Intravenous thrombolysis is contraindicated in acute ischemic stroke secondary to infective endocarditis. We report our initial experience in 6 cases of proximal vessel occlusion treated with mechanical thrombectomy, which was safe (no bleeding) and effective (significant early neurological improvement) and might be useful in this clinical setting.

Twenty-year experience with cryopreserved arterial allografts for vascular infections†

OBJECTIVES The aim of this study was to analyse outcomes over 2 decades using cryopreserved vascular allografts to treat vascular infection. METHODS We conducted a retrospective study of patients identified from our institutional database who were treated for primary or secondary vascular infection using implanted allografts. RESULTS Between October 1992 and May 2014, 54 patients underwent surgery for vascular infection out of 118 patients implanted with cryopreserved vascular allografts. The 52 patients for whom we had full information form the basis of the study with a 96% follow-up. The average age was 64 ± 11 years; 87% were men; 65% had previous vascular surgery; 19% had emergency operations. A total of 75% of the patients had aortoiliofemoral infections. Five patients underwent surgery with cardiopulmonary bypass. Fifty percent required more than 1 allograft and 15% had concomitant procedures. Seventy-three percent (38/52) of specimen cultures yielded positive results with polymicrobial flora in 29%. Surgical specimens most frequently grew coagulase-negative staphylococci. The early postoperative reoperation rate was 15% for allograft-related complications. There were 20 (38%) early deaths, including deaths of acute myocardial infarction, anastomosis rupture and persistent sepsis and shock. Uncontrolled infection leading to septic shock and multiple organ failure was the cause of death in 50% of the cases. The mean duration of freedom from allograft reintervention was 12.2 years. The mean duration of freedom from allograft occlusion or limb loss was 12.1 years [95% confidence interval (CI) 9.9-14.4]. Of the 32 surviving patients, we had patency information for 66% obtained by angiography or computed tomography. The mean survival for the cohort was 5.9 years (95% CI 3.9-7.8). Mean freedom from cardiovascular infection-related death was 9.3 years (95% CI 7.2-11.4). CONCLUSIONS Allografts can be indicated for treatment of primary/secondary infection and have remarkable results in multimorbid patients. Patients with vascular infection have a high-risk profile, around 40% mortality during the first 6 months, with reduction in overall mortality thereafter. We believe that allografts may play a role in the surgical treatment of vascular infection.