Antonio Menichetti

Peripheral Extracorporeal Membrane Oxygenation System as Salvage Treatment of Patients With Refractory Cardiogenic Shock: Preliminary Outcome Evaluation

The novel Permanent Life Support (PLS; Maquet, Jostra Medizintechnik AG, Hirrlingen, Germany) as peripheral veno-arterial extracorporeal membrane oxygenation (ECMO) support system has been investigated as treatment for patients with refractory cardiogenic shock (CS). Between January 2007 and July 2011, 73 consecutive adult patients were supported on peripheral PLS ECMO system at our institution (55 men; age 60.3 ± 11.6 years, range: 23-84 years). Indications for support were failure to wean from cardiopulmonary bypass in the setting of postcardiotomy (n = 50) and primary donor graft failure (n = 8), post-acute myocardial infarction CS (n = 12), and CS on chronic heart failure (n = 3). Mean support time was 10.9 ± 7.6 days (range: 2-34 days). Overall, 26 (35.6%) patients died on ECMO. Among survivors on ECMO, 44 (60.2%) patients were successfully weaned from support, and three (4.1%) were switched to a mid-long-term ventricular assist device. Thirty-three (45.2%) were successfully discharged. The following variables were significantly different if survivors and nonsurvivors on ECMO were compared: age (P = 0.04), female gender (P < 0.01), cardiopulmonary resuscitation before ECMO (P < 0.01), lactate level before ECMO (P = 0.01), number of platelets, fresh frozen plasma units, and packed red blood cells (PRBCs) transfused during ECMO support (P = 0.03, P = 0.02, and P < 0.01), blood lactate level (P = 0.01), and creatine kinase isoenzyme MB (CK-MB) relative index 72 h after ECMO initiation (P < 0.001), and multiple organ failure on ECMO (P < 0.01). Stepwise logistic regression identified blood lactate level and CK-MB relative index at 72 h after ECMO initiation, and number of PRBCs transfused on ECMO as significant predictors of mortality on ECMO (P = 0.011, odds ratio [OR] = 2.48; 95% confidence interval [CI] = 1.11-3.12; P = 0.012, OR = 2.81, 95% CI = 1.026-2.531; and P = 0.012, OR = 1.94, 95% CI = 1.02-5.21; respectively). Patients with an initial poor hemodynamic status could benefit by rapid peripheral installation of PLS ECMO. The blood lactate level, CK-MB relative index, and PRBCs transfused should be strictly monitored during ECMO support.

Levosimendan Versus Intra-aortic Balloon Pump in High-Risk Cardiac Surgery Patients

OBJECTIVE Patients with severe left ventricular dysfunction receive inotropic and mechanical circulatory support with an intra-aortic balloon pump (IABP) during the perioperative phase of cardiac surgery. The authors performed the first comparison of levosimendan versus an IABP in patients with poor left ventricular function undergoing cardiac surgery. DESIGN A case-matched study. SETTING A teaching hospital. PARTICIPANTS Twenty-two heart failure patients scheduled to undergo elective coronary artery bypass graft surgery with or without concomitant mitral surgery. INTERVENTIONS Eleven patients received levosimendan at a dose of 0.1 μg/kg/min for 24 hours without an initial bolus. The control group, also 11 patients, received a preoperative IABP. The intensive care unit stay was the major endpoint of this study. Biochemical, hemodynamic, and echocardiographic data were collected together with the time on mechanical ventilation and 30-day mortality. MEASUREMENTS AND MAIN RESULTS The length of intensive care unit stay was reduced in patients receiving levosimendan (median, 2.5; range, 1-3 days) compared with those receiving an IABP (median, 5; range, 3-6 days; p = 0.01). No deaths occurred in the levosimendan group; 1 patient died in the intra-aortic balloon pump group. CONCLUSIONS Patients receiving levosimendan had a shorter duration of intensive care stay than peers who received a preoperative IABP. The findings of this pilot study should be investigated further in a large randomized controlled study.

Calcium Chloride Minimizes the Hemodynamic Effects of Propofol in Patients Undergoing Coronary Artery Bypass Grafting

OBJECTIVE To assess the hemodynamic effects of propofol and the counteracting effect of calcium chloride (CaCl2) in patients undergoing coronary artery bypass grafting (CABG). DESIGN Prospective, randomized study. SETTING University hospital, department of cardiac surgery. PARTICIPANTS Fifty-eight patients undergoing elective CABG, divided into group A (n = 29) and group B (n = 29). INTERVENTIONS Anesthesia was induced with a combination of fentanyl, 7 microg/kg; pancuronium, 0.1 mg/kg; and propofol, 1.5 mg/kg, administered over 60 seconds. A blinded investigator administered saline in group A patients and 10 mg/kg of CaCl2 in group B patients at the same speed and same time as propofol administration through another lumen of the central venous catheter. MEASUREMENTS AND MAIN RESULTS Hemodynamic data were obtained at baseline (T0), 2 minutes after anesthesia induction (T1), and 2 minutes after tracheal intubation (T2). Heart rate decreased significantly in group A patients (86.2+/-11.3 beats/min at T0 and 72.8+/-7.5 beats/min at T2; p < 0.001). Mean arterial pressure decreased significantly in patients in both groups (group A, 108.0+/-12.0 mmHg at T0; 74.6+/-14.6mmHg at T2;p < 0.001 and group B, 106.0+/-10.2 mmHg at T0; 90.4+/-10.0 mmHg at T2; p < 0.05). Stroke volume index, cardiac index, and cardiac output decreased in group A patients (39.4+/-4.1 mL/beat/m2 at T0 and 28.8+/-5.2 mL/beat/m2 at T2; p < 0.05; 3.4+/-0.6 L/min/m2 at T0 and 1.9+/-0.3 L/min/m2 at T2; p < 0.001; 5.9+/-0.9 L/min at T0 and 3.4+/-0.4 L/min at T2; p < 0.001, respectively), whereas in group B patients, changes were negligible (38.1+/-7.0 mL/beat/m2 at T0 v 35.7+/-6.6 mL/beat/m2 at T2; (NS) 3.3+/-0.5 L/min/m2 at T0 v 2.7+/-0.3 L/min/m2 at T2; (NS) 5.7+/-0.9 L/min at T0 v 4.7+/-0.5 L/min at T2; (NS), respectively). CONCLUSION Simultaneous administration of CaCl2 during the induction of anesthesia minimizes the potential negative effect of propofol on cardiac function in cardiac patients.

Weaning From Venovenous Extracorporeal Membrane Oxygenation Without Anticoagulation: Is it Possible?

A 19-year-old man affected with severe acute respiratory distress syndrome that was unresponsive to medical treatment was successfully weaned without anticoagulation therapy from venovenous extracorporeal membrane oxygenation (ECMO) because of life-threatening bleeding. The patient received venovenous ECMO with double peripheral cannulation. Heparin infusion was discontinued on day 10 for severe bleeding from thoracic and mediastinal drainages until the ECMO was removed. The weaning was performed while keeping the blood flow unchanged, only gas flows were gradually decreased. The patient was discontinued from ECMO and extubated after pulmonary function improved. Based on this single experience, management and weaning without any anticoagulant agent might be possible.

Severe Intra-aortic Balloon Pump Complications: A Single-Center 12-Year Experience

OBJECTIVE An intra-aortic balloon pump (IABP) is used routinely in high-risk patients undergoing cardiac surgery to prevent or treat low-cardiac-output syndrome and to reduce perioperative mortality. The insertion and management of IABP carry the risk of major vascular complications. The authors reviewed their database to ascertain the incidence of IABP-related severe complications. DESIGN A retrospective study. SETTING A teaching hospital. PARTICIPANTS Ten thousand three hundred sixty-five patients scheduled for elective or emergency cardiac surgery over a 12-year period at a single center. INTERVENTIONS Four hundred twenty-three patients received an IABP perioperatively. Careful preoperative screening for peripheral arterial disease, strict postoperative control, and the sheathless insertion technique to spare the arterial flow to the lower limb were performed routinely. MEASUREMENTS AND MAIN RESULTS The use of a perioperative IABP was 0.7% at the beginning of the observation period in 1999 and 7.3% in 2010, showing a fluctuating trend. Two patients (0.47%) died of direct complications, arterial wall damage and bleeding. Immediate surgical exploration and control of bleeding were followed by multiple-organ failure and death. Vascular complications, leading to lower-limb ischemia, occurred in 4 of 423 patients (0.94%). All of them underwent urgent vascular surgery and survived. Local sepsis occurred in 2 other patients (0.47%). CONCLUSIONS These data indicate that an IABP is a valuable option in high-risk patients undergoing cardiac surgery even if not devoid of intrinsic risks for vascular complications (0.94%), septic complications (0.47%) and mortality (0.47%).

Color Doppler imaging of the retinal vessels during repair of aortic dissection

C EREBRAL HYPOPERFUSION during cardiovascular surgery represents a significant burden and may produce physical deficits, psychologic deficits, or both. 1 Perioperative neurologic damage may be caused by intraoperative embolism, deep hypothermic circulatory arrest, nonpulsatile flow of extracorporeal circulation, unrecognized carotid artery stenosis, or transient occlusion of a carotid artery by the infimal flap during repair of dissection. Transcranial Doppler can be used to measure cerebral blood flow during cardiac surgery, but this technique is not feasible in all patients, particularly in the elderly because of the increased thickness of the temporal bone, which attenuates the Doppler beam. Other methods to monitor cerebral blood flow and neuron metabolism, such as electroencephalography, evoked potentials, carotid echography, transcranial Doppler, fluorescein angiography, and study of biochemical markers of neuronal and glial damage, have yielded inconclusive results. High-resolution color Doppler imaging allows visualization of the central retinal artery and measurement of its blood flow velocity, 2,3 which reflects internal carotid artery flow. Orihashi et al 4 described central retinal artery and mtrobulbar vessel flow during coronary artery bypass grafting, valvular replacement, and aortic surgery. The authors describe more extensive imaging of the retinal vessels, including peripheral intrabulbar branches, during retrograde cerebral perfusion for repair of aortic dissection and discuss the potential impact of this technique in cardiac surgery.

Neuromuscular relaxants in non-cardiac surgery after cardiomyoplasty

PurposeDynamic cardiomyoplasty is a therapeutic alternative to heart transplantation in irreversible cardiac insufficiency. Little information exists about the use of muscle relaxants in patients with cardiomyoplasty. In particular, it is not clear if the muscle flap is responsive to neuromuscular blockers. The purpose of this report is to describe the safe use of vecuronium in a patient with cardiomyoplasty.Clinical featuresA 59-yr-old man, after cardiomyoplasty for dilated cardiomyopathy two years earlier, underwent general anaesthesia with fentanyl, propofol and vecuronium during surgery for intestinal ischaemia. Intraoperative transthoracic echocardiography showed that vecuronium did not affect muscle flap motion. Two days after surgery he died in septic shock. Post-mortem histological and immunohistochemical examination showed nervous degeneration of the flap probably as a result of the chronic low frequency pacing. There was also an increase in extrajunctional receptors and an alteration in junctional receptors, as demonstrated by the negative reaction to anti-synaptophysin antibodies, used to identify the neuromuscular plate.ConclusionIn patients undergoing non-cardiac surgery after previous cardiomyoplasty, muscle relaxants, such as vecuronium, may be used safely. Depolarising agents, such as succinylcholine, should probably be avoided because of the possible exaggerated actions on extrajunctional receptors.RésuméObjectifLa cardiomyoplastie dynamique est une alternative thérapeutique à la greffe cardiaque dans l’insuffisance cardiaque irréversible. Il existe peu d’information sur l’utilisation des relaxants musculaires chez les patients ayant subi une cardiomyoplastie. De façon plus précise, la réponse du lambeau musculaire aux bloqueurs neuromusculaires est controversée. Le but de cet article est de décrire l’utilisation sécuritaire du vécuronium chez un patient ayant subi une cardiomyoplastie.Aspects cliniquesUn homme de 59 ans, ayant subi une cardiomyoplastie il y a 2 ans pour une cardiomyopathie, a subi une anesthésie générale à base de fentanyl, propofol et vécuronium pour une chirurgie pour ischémie intestinale. Une échographie transthoracique peropératoire a démontré que le vécuronium ne modifiait pas le mouvement du lambeau musculaire. Deux jours après son opération il est décédé de choc septique. L’examen post-mortem tant histologique qu’immunohistochimique a montré une dégénérescence du tissu nerveux du lambeau, probablement comme conséquence de la stimulation chronique à basse fréquence. On retrouvait aussi une augmentation des récepteurs membranaires extrajonctionnels et une altération des récepteurs jonctionnels, tel que démontré par la réaction négative aux anticorps antisynaptophysine, utilisés pour identifier les jonctions neuromusculaires.ConclusionChez les patients subissant une chirurgie non cardiaque après cardiomyoplastie, les relaxants musculaires, tel le vécuronium, peuvent être utilisés sécuritairement. Les agents dépolarisants, tel la succinylcholine, devraient probablement être évités à cause des risques d’effets excessifs sur les récepteurs extrajonctionnels.