Volume guarantee ventilation during surgical closure of patent ductus arteriosus.

BACKGROUND: Surgical closure of patent ductus arteriosus (PDA) is associated with adverse outcomes. Surgical exposure requires retraction of the lung, resulting in decreased aeration and compliance. Optimal respiratory support for PDA surgery is unknown. Experience with volume guarantee (VG) ventilation at our institution led us to hypothesize that surgery would be better tolerated with automatic adjustment of pressure by VG to maintain tidal volume (VT) during retraction. OBJECTIVE: The objective of this study was to describe ventilator support, VT, and oxygenation of infants supported with VG during PDA surgery. DESIGN/METHODS: Ventilator variables, oxygen saturation, and heart rate were recorded during PDA surgery in a convenience sample of infants during PDA closure on VG. Pressure limit increased 11% and set VT was 26% lower during lung retraction. Fentanyl and pancuronium/vecuronium were used for anesthesia/muscle relaxation. Longitudinal data were analyzed by analysis of variance for repeated measures. RESULTS: Seven infants, 25.4 ± 1.5 weeks and 723 ± 141 g, underwent closure of PDA on VG at a mean age 29.9 days. No air leak, bradycardia, or death occurred. Target VT was maintained with a modest increase in inflation pressure. Oxygenation remained adequate. CONCLUSIONS: VG avoided hypoxemia and maintained adequate VT with only a modest increase in peak inflation pressure and thus may be a useful mode during PDA surgery.

No effect of a homoeopathic combination of Arnica montana and Bryonia alba on bleeding, inflammation, and ischaemia after aortic valve surgery.

AIMS: " Arnica montana is a popular homoeopathic treatment with potential haemostatic and anti-inflammatory properties. A homoeopathic combination of A. montana and Bryonia alba was used in aortic valve surgery to evaluate its effectiveness in reducing bleeding, inflammation, pain and myocardial ischaemia. METHODS: One day before surgery, 92 adult patients were randomly assigned to a double-blind parallel trial with either homoeopathic granules or a matching placebo until 4 days after surgery. The primary outcome was the volume of blood/liquid in the drains at their removal. The secondary outcomes included postoperative blood/liquid losses at 12 and 24 h as well as C-reactive protein (CRP), pain, temperature and plasma troponin Ic. RESULTS: At 12 h and 24 h after surgery, then at drain removal, blood losses in homoeopathy and placebo groups were not statistically significant (362 +/- 218, 520 +/- 269 and 640 +/- 297 ml vs. 456 +/- 440, 620 +/- 477 and 796 +/- 717 ml; P= 0.19, 0.23 and 0.35, respectively). The statistical modelling did not show significantly different patterns of CRP, troponin and body temperature changes or of pain perception. The number of transfused packed red cells was not significantly different either (P= 0.58). Two patients from each group died during the study period and the number of serious adverse events was not statistically different (six in homoeopathy vs. 10 in placebo groups; Fisher's exact test P= 0.41). CONCLUSIONS: In the study setting, there was no evidence of effects of A. montana and B. alba combination on bleeding, inflammation, pain or myocardial ischaemia.

Lack of cardiovascular stimulation during endotracheal intubation in cardiac surgical patients anesthetized with diazepam-ketamine-pancuronium.

Anesthesia was induced with diazepam-ketamine-pancuronium in 12 adult patients scheduled for cardiac surgery. Intubation caused no significant changes in arterial blood pressure, heart rate, or plasma levels of norepinephrine and epinephrine. Circulatory stability was an advantage in critically ill patients.

Vecuronium: a new nondepolarizing neuromuscular-blocking agent. Clinical pharmacology, pharmacokinetics, cardiovascular effects and use in special clinical situations.

Vecuronium provides additional flexibility to the clinician using neuromuscular-blocking drugs. Its shorter duration of action, lack of significant cardiovascular effects and lack of dependence on the kidney for elimination provide clinical advantages over, or alternatives to, currently available, nondepolarizing neuromuscular-blocking drugs.

Acupuncture anesthesia for open heart surgery: a report of 800 cases.

This article reports the utilization of acupuncture in combination with chemical anesthesia and neuromuscular relaxant for patients with cardiac surgery, including valvular disease and by-pass. In 800 patients studied using this type of combination of anesthetic techniques, it was found that this procedure can be successful for cardiac surgery and that it allows light planes of anesthesia with less interference to circulatory regulation. There is a certain advantage of using acupuncture anesthesia when compared with chemical anesthesia, as the pharmacological agents are not used and hence post no metabolic load for the patients. From the 800 patients studied, it seems justifiable to recommend this anesthetic procedure for cardiac surgery.

[Is it necessary to discontinue captopril before heart surgery?]. / Faut-il arrêter le captopril avant l'opération en chirurgie cardiaque?

Interaction between kininase II and anaesthesia is not well described. Twenty two patients treated by kininase II for congestive heart failure are studied during anaesthesia for cardiovascular surgery. A first group of seventeen homogeneous hemodynamic data are reported. High cardiac index contrasts with severe clinical cardiac failure. A second group of inhomogeneous patients are separately described. Vasoconstrictor can be codified in the situation of low systemic resistance with high cardiac index. Preoperative treatment can be continued, under requirement of hemodynamic monitoring.

[Rocuronium (esmerone) in anesthesia during surgery under extracorporeal circulation]. / Rokuronium (ésmeron) pri anesteziologicheskom obespechenii operatsii s iskusstvennym krovoobrashcheniem.

The study was undertaken to examine the myoplegic, hemodynamic, and histamine-releasing effects of the new aminosteroidal myorelaxant Rocuronium (esmerone, Organon firm) used to maintain anesthesia in cardiac surgical patients by orienting to early tracheal extubation. Twenty two patients aged 50 +/- 3 years operated on under extracorporeal circulation were examined. At the initial stage of maintenance, the agent in a dose of 0.6 mg/kg failed to affect cardiac pump function and to elevate plasma histamine levels. A moderate vagolytic effect was shown in 45% of cases. The incidence of myoplegia reduced in patients with significant circulatory insufficiency. In the preperfusion period, Rocuronium in a dose of 10.2 +/- 0.9 micrograms/kg/min blocked neuromuscular conduction (NMC) at a level of 5.1 +/- 1.8 to 19.2 +/- 3.5%. During hypothermic extracorporeal circulation and postperfusion period, the dosage of the myorelaxant substantially decreased. After termination of Rocuronium infusion, the time of up to 95%-recovery of NMC was 63 +/- 6 min. Early tracheal extubation was conducted in 68% of the patients 69 +/- 7.6 min after the end of the operation. Residual myoplegia was absent. The predictable recovery of NMC following the use of Rocuronium creates conditions for early activation of patients operated on under extracorporeal circulation.

[Clinical, neurophysiological and hemodynamic effects of a new nondepolarizing myorelaxant mivacurium in heart surgery patients]. / Klinicheskie, neirofiziologicheskie i gemodinamicheskie éffekty novogo nedepoliarizuiushchego miorelaksanta mivakuriuma u kardiokhirurgicheskikh bol'nykh.

Thirty patients aged 23 to 65 years with ASA class III operated on the heart under total intravenous anesthesia were examined after the Good Clinical Practice protocol. Mivacurium in bolus dose of 0.2 mg/kg was injected for intubation of the trachea; neuromuscular blocking (NMB) was maintained by a repeated injection of the drug in a dose of 0.15 mg/kg, after which it was infused at a rate of 1 to 10 micrograms/kg/min. Accelerometric control of neuromuscular conduction was carried out by the Organon (Belgium) TOF-Guard device. Central and peripheral hemodynamics was monitored. Side effects of the drug were recorded. Bolus injection of mivacurium in a dose of 0.2 mg/kg caused T1 suppression (90%) after 2.6 +/- 0.7 min. Maximal (97.7 +/- 4.5%) suppression was observed after 4.17 +/- 2.5 min. The conditions of intubation of the trachea after 3.9 +/- 1.8 min in the presence of 78 to 100% T1 suppression (97.7 +/- 4.5%) were considered excellent or good in 96.6% of cases. Clinically and neurophysiologically sufficient muscle relaxation after the first injection of the drug persisted for 27.7 +/- 7.3 min. Minimal rate of infusion for maintaining the NMB at 95 +/- 4% level of T1 suppression was 6.3 +/- 1.7 micrograms/kg/min. Bolus injection of mivacurium in a dose of 0.2 mg/kg for 60 sec involved a 1-3-min drop of the mean arterial pressure by 10.5% and a 10.3% decrease of heart rate. Repeated bolus injection of the drug in a dose of 0.15 mg/kg and its infusion did not change the peripheral and central hemodynamics. The most typical side effect of the drug in a dose of 0.2 mg/kg is short-term reversible reddening of the skin of the face and neck, observed in 20% of patients. The results permit us to consider mivacurium as an effective, safe, and controllable agent, which can be used in cardiosurgical patients.

Heparin brand is associated with postsurgical outcomes in children undergoing cardiac surgery.

BACKGROUND: We sought to determine whether the use of specific unfractionated heparin brands during cardiopulmonary bypass for pediatric cardiac surgery was associated with differences in postoperative outcomes, especially regarding the incidence of bleeding and thromboembolic complications. METHODS: We compared postoperative outcomes for pediatric cardiac surgeries performed with Hepalean (Organon Teknika) to those performed with PPC heparin (Pharmaceutical Partners of Canada). Differences in clinical outcomes were determined in multivariable logistic and linear regression models adjusted for patients and surgery characteristics. RESULTS: In all, 903 operations were reviewed, 289 (32%) using Hepalean and 614 (68%) using PPC heparin. Patient demographics and surgical variables were comparable between groups. In multivariable regression models, adjusted for patients' characteristics, heparin use and choice of antifibrinolytic agents, the use of PPC heparin was associated with greater use of red blood cell transfusions in the first 48 postoperative hours (estimates +1.6 mL/kg, p<0.001), increased odds of bleeding complications (odds ratio 3.8, p=0.04), thromboembolic complications (odds ratio 4.7, p=0.01), early unplanned reoperation (odds ratio 6.9, p=0.03), longer postoperative intensive care unit stay (estimate +3.2 days, p<0.001), and longer hospital stay (estimate +3.6 days, p<0.001). CONCLUSIONS: Brand of unfractionated heparin used during cardiopulmonary bypass for pediatric cardiac surgery was associated with bleeding complications and clinical outcomes. Different brands of unfractionated heparin should not be considered equivalent without proper validation in formal trials.

Similar preoperative hemodynamic response to pancuronium and rocuronium in high-risk cardiac surgical patients.

AIM: Rocuronium may be a good alternative to pancuronium in cardiac surgical patients. We evaluate the hemodynamic response to rocuronium and pancuronium administered to cardiac surgical patients. METHODS: A single-blind, randomized clinical trial was carried out at the National Institute of Cardiology in Mexico. Twenty-two patients older than 18 years, NYHA class III-IV, and scheduled to undergo an elective cardiovascular surgical procedure were enrolled. Patients were randomly allocated to receive an i.v. bolus dose of either pancuronium 100 microg/kg or rocuronium 600 microg/kg. Peripheral arterial (radial) and venous cannulations and insertion of a multi-lumen pulmonary artery flotation catheter through the right internal jugular vein were carried out under local anesthesia. Anesthetic induction with an i.v. bolus dose of fentanyl 700 microg and diazepam 20 mg was performed and thereafter the neuromuscular blocking agent was administered. Ventilation with O2 100% was performed until a TOF < or =5% was observed and tracheal intubation was performed. After intubation, patients were maintained with O2 10 mL/kg administered by means of a pulmonary ventilator at a pressure of 20-25 cm H2O. The basal, pre-laryngoscopy, post-intubation, and pre-operative recording of a set of cardiovascular parameters were obtained. RESULTS: No differences (P>0.05) in the hemodynamic response were observed between pancuronium and rocuronium nor during the different evaluation times in each group. CONCLUSIONS: Rocuronium can be a safe alternative to pancuronium for patients requiring cardiac surgical procedures.

Prolonged (more than ten hours) neuromuscular blockade after cardiac surgery: report of two cases.

PURPOSE: We examine two cases of prolonged neuromuscular blockade (NMB) after cardiac surgery. To the best of our knowledge, these are the first reported cases of complete paralysis lasting more than ten hours after surgery. CLINICAL FEATURES: We attribute the extended durations of NMB (more than ten hours) to high doses of NMB drugs in combination with magnesium sulphate and moderate renal failure. Advanced age, hepatic disease, aminoglycoside exposure, hypocalcemia, and possible interaction between rocuronium and pancuronium may have played minor roles. CONCLUSION: We should avoid administering large doses of NMB agents, even in the context of planned postoperative ventilation. If NMB is not monitored intraoperatively in patients who are at risk of prolonged NMB, then train-of-four response should be measured in the intensive care unit. Adequate sedation should be provided until proper recovery of neuromuscular function is documented.

[Anesthesia for cardiovascular surgery under extracorporeal circulation: the authors' own technic]. / Anestesia per chirurgia cardiovascolare in C.E.C.: una tecnica personale.

The A. describe a technique of general anaesthesia for open-heart surgery, induced with Althesin and Fentanyl, in 29 patients submitted to cardiac and aortic surgery, and relate the results obtained. The experience showed the effectiveness of the reduction of peripheral vascular resistances due to Althesin, as well as usefulness of collateral techniques (cortisonic drug, carbon dioxide mixture, hypothermia, beta-adrenergic block, coronary vasodilation) employed for these patients during cardiopulmonary bypass.

Fentanyl- and sufentanil-oxygen-pancuronium anesthesia for cardiac surgery in infants.

The safety and efficacy of fentanyl-oxygen (50 and 75 micrograms/kg) and sufentanil-oxygen (5 and 10 micrograms/kg) were studied in 40 infants undergoing repair of complex heart defects. When fentanyl or sufentanil was given simultaneously with pancuronium, induction of anesthesia was rapid and smooth with only mild and clinically insignificant hemodynamic changes. Hemodynamic responses to tracheal intubation were completely blocked, whereas hemodynamic responses to surgical incision and sternotomy were partially and variably blocked. Except for somewhat more effective blocking of responses to surgical stimulation by sufentanil, the effects of both narcotics were similar. No significant differences in effects were found between the two dose levels of either drug. Transcutaneous oxygen tensions increased with induction, intubation, and surgical stimulation with both fentanyl and sufentanil, even in cyanotic patients with right to left shunts. Fentanyl- and sufentanil-oxygen-pancuronium anesthesia were both safe and effective for cardiac surgery in infants. This study raises the question of possible beneficial effects of high dose fentanyl and sufentanil in blunting stress responses in the pulmonary circulation, a critical aspect of anesthesia and intensive care in the infant and neonate.

The effect of paralysis on oxygen consumption in normoxic children after cardiac surgery.

To determine whether paralysis reduces oxygen consumption (V02) after cardiac surgery in infants, the authors measured V02 before and after paralysis in 17 sedated infants who were ventilated mechanically after cardiac surgery. Oxygen consumption was determined as being the difference between oxygen content of inspired and expired gases. The absence or presence of "movement" (breathing or repeated movement of the extremities) before paralysis was noted. For eight infants who did not "move" before paralysis, VO2 was similar before (9.1 +/- 1.2 ml . kg-1 . min-1, mean +/- SD) and after (9.0 +/- 1.5 ml . kg-1 . min-1) paralysis (P = 0.81). However, for nine infants who did "move" before paralysis, VO2 decreased from 9.2 +/- 1.4 ml . kg-1 . min-1 before paralysis to 8.0 +/- 1.4 ml . kg-1 . min-1 after paralysis (P less than 0.05). One infant in each group had an increase in VO2 greater than 10% of the baseline value (i.e., 12% and 14%). In conclusion, if breathing or repeated movement is present before paralysis, paralysis decreases VO2 by 13% in sedated infants after cardiac surgery. If repeated or regular movement is not present before paralysis, paralysis does not decrease VO2. These data suggest that in normoxic patients, muscle paralysis does not significantly alter V02 and therefore should not be used for this purpose.