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LETTERS TO THE EDITOR
population. Following surgical correction of tetralogy of Fallot there is a 35% to 40% incidence of right upper lobe atelectasis, which usually becomes evident on the chest roentgenogram 6 to 10 hours postoperatively. The same incidence of postoperative right upper lobe atelectasis is seen in our children with Down syndrome after repair of an AV canal. In each case, malposition or temporary displacement of the nasotracheal tube was excluded. The orifice of the right upper lobe bronchus is generally found on the lateral side of the right main bronchus just below the carina. We wish to raise the question whether certain congenital malformations would predispose these children to right upper lobe atelectasis. An aberrant right upper lobe bronchus leaving the trachea above the carina could explain our findings. Hubert Böhrer, MD Alfons Bach, MD Johann Motsch, MD
REFERENCE
Department of Anesthesia University of Heidelberg Heidelberg, Germany
1. Jain U, Rao TLK, Kleinman BS, et al: Radiographic pulmonary abnormalities after different types of cardiac surgery. J Cardiothorac Vast Anesth 5:592-595,199l
Combination
of Pancuronium
and Vecuronium
To the Editor:
1 was interested to read the article “Hemodynamic Responses to Pancuronium and Vecuronium During High-Dose Fentanyl Anesthesia for Coronary Artery Bypass Grafting.“’ The authors have compared pancuronium and vecuronium, which have different effects on cardiovascular parameters, namely pancuronium has a propensity to increase heart rate and arterial blood pressure, and vecuronium, though associated with marked cardiovascular stability, does not counter the bradycardia in a narcotic-based anesthetic. These differences in clinical characteristics offer some advantage in combining the two drugs in clinical practice. It appears logica1 to mix pancuronium and vecuronium in an attempt to minimize the cardiac stimulation due to pancuronium at the same time preventing bradycardia associated with the use of vecuronium. We combined pancuronium and vecuronium in a 1:l concentration and found that the margin of safety in terms of myocardial Oz supply/demand can be increased when the pancuronium-vecuronium mixture is used rather than when pancuronium is used alone.2 K. Muralidhar, MD
Department of Anaesthesiology B.M. Birla Heart Research Centre Calcutta, India REFERENCES
1. Paulissian R, Mahdi M, Joseph NJ, et al: Hemodynamic Responses to Pancuronium and Vecuronium during high-dose Fentanyl anesthesia for Coronary artery bypass grafting. J Cardiothorac Vast Anesth 5:120-125,199l.
2. Muralidhar K, Bhanumurthy S: Pancuronium and Vecuronium mixture for coronary artery bypass grafting. J Anesth Clin Pharmacol6:5-9,199O.
LETTERS TO THE EDITOR
population. Following surgical correction of tetralogy of Fallot there is a 35% to 40% incidence of right upper lobe atelectasis, which usually becomes evident on the chest roentgenogram 6 to 10 hours postoperatively. The same incidence of postoperative right upper lobe atelectasis is seen in our children with Down syndrome after repair of an AV canal. In each case, malposition or temporary displacement of the nasotracheal tube was excluded. The orifice of the right upper lobe bronchus is generally found on the lateral side of the right main bronchus just below the carina. We wish to raise the question whether certain congenital malformations would predispose these children to right upper lobe atelectasis. An aberrant right upper lobe bronchus leaving the trachea above the carina could explain our findings. Hubert Böhrer, MD Alfons Bach, MD Johann Motsch, MD
REFERENCE
Department of Anesthesia University of Heidelberg Heidelberg, Germany
1. Jain U, Rao TLK, Kleinman BS, et al: Radiographic pulmonary abnormalities after different types of cardiac surgery. J Cardiothorac Vast Anesth 5:592-595,199l
Combination
of Pancuronium
and Vecuronium
To the Editor:
1 was interested to read the article “Hemodynamic Responses to Pancuronium and Vecuronium During High-Dose Fentanyl Anesthesia for Coronary Artery Bypass Grafting.“’ The authors have compared pancuronium and vecuronium, which have different effects on cardiovascular parameters, namely pancuronium has a propensity to increase heart rate and arterial blood pressure, and vecuronium, though associated with marked cardiovascular stability, does not counter the bradycardia in a narcotic-based anesthetic. These differences in clinical characteristics offer some advantage in combining the two drugs in clinical practice. It appears logica1 to mix pancuronium and vecuronium in an attempt to minimize the cardiac stimulation due to pancuronium at the same time preventing bradycardia associated with the use of vecuronium. We combined pancuronium and vecuronium in a 1:l concentration and found that the margin of safety in terms of myocardial Oz supply/demand can be increased when the pancuronium-vecuronium mixture is used rather than when pancuronium is used alone.2 K. Muralidhar, MD
Department of Anaesthesiology B.M. Birla Heart Research Centre Calcutta, India REFERENCES
1. Paulissian R, Mahdi M, Joseph NJ, et al: Hemodynamic Responses to Pancuronium and Vecuronium during high-dose Fentanyl anesthesia for Coronary artery bypass grafting. J Cardiothorac Vast Anesth 5:120-125,199l.
2. Muralidhar K, Bhanumurthy S: Pancuronium and Vecuronium mixture for coronary artery bypass grafting. J Anesth Clin Pharmacol6:5-9,199O.
