263
LETTERS TO THE EDITOR
nique of limited excursion ventilation. Crit Care Med 19:10861089,199l 4. Bowen TE, Fishback ME, Green DC: Treatment of refractory atelectasis. Ann Torac Surg 18:584-589,1974 5. Sachdeva SP: Treatment of postoperative pulmonary atelecta-
Hoarseness
and Vocal
Cord Paralysis
sis by active inflation of the atelectatic lobe(s) through an endotracheal tube. Acta Anaesth Stand l&65-70,1974 6. Fowler III AA, Scoggins WG, O’Donohue WJ Jr: Positive end-expiratory pressure in the management of lobar atelectasis. Chest 74:497-500, 1978
Following
Coronary
Artery Bypass
Surgery
To the Editor: Hoarseness endotracheal
following intubation
coronary artery bypass surgery (CABG) is a frequent complication and is usually attributed to or to internal jugular vein cannulation. From our experience, it is usually self-limiting and
disappears after the second or third postoperative day. To explore the possible causes and to examine the incidence of this disturbing complication, we performed the following study. This study was approved by the Institutional Review Board for human experimentation. Seven hundred fifty patients, aged 40 to 72 years of age, undergoing elective CABG were studied. There were 340 women and 410 men. Patients with prior history of hoarseness, difficult intubation, prior endotracheal intubation, or prolonged postoperative ventilation were excluded from the study. A 9-mm endotracheal tube was used in all male patients and an g-mm endotracheal tube was used in all female patients. All tracheal intubations were achieved atraumatically, using a 3-Macintosh blade. The endotracheal tube cuffs were inflated with air up to an intracuff pressure of 20 cm H,O (measured with a cufflator designed to measure high-volume low-pressure cuffs). They were mechanically ventilated using a tidal volume sufficient to maintain a PaCO, between 35 to 40 mm Hg during surgery and F,O, of 1. The endotracheal tube used was the “Lo Pro” cuffed tracheal tube with a Murphy eye made by Mallinckrodt Critical Care (Glens Falls, NY). Postoperatively, all patients were mechanically ventilated after 12 to 15 hours, using intermittent mandatory ventilation. Following sternotomy all the patients had dissection of the left internal mammary artery. Fifty patients had bilateral dissection of the internal mammary artery. Theinternal mammary artery was exposed using a Favaloro self-retaining sternal retractor. Once the pleura was divided, the internal mammary artery was isolated from the sixth intercostal space to the level of the first rib using low-voltage electrocoagulation (1.5 to 20 W). The patients were then given heparin, 4 mg/kg, cannulated, and cardiopulmonary bypass begun, during which the patients were cooled down to 27°C (bladder). The heart was protected using cold blood cardioplegia and cold topical irrigating saline solution. (No isolation pad was used.) Myocardial temperature was recorded using the Mon-a-therm myocardial temperature sensor (model 6500; Mon-a-therm Inc, St Louis, MO). All patients were examined daily for hoarseness for 5 days by a critical care nurse who had visited them the day before surgery. They were tested for hoarseness every hour after extubation for 6 hours, then every 8 hours during the first postoperative day. If hoarseness persisted for more than 2 days, an indirect laryngoscopy was performed by an otolaryngologist. Eighty-four patients exhibited hoarseness following removal of the endotracheal tube (Table I). Fifty patients remained hoarse after the third postoperative day and required indirect laryngoscopy. On the fifth postoperative day, only 10 of them were still hoarse, 5 had left vocal cord paralysis and were discharged after the tenth postoperative day. Examination of these five patients 3 weeks postoperatively showed arytenoid movement. Vocal cord function returned to normal by 8 weeks postoperative; none of these patients developed neurological complications (stroke:). Dissection of right and left internal mammary artery was performed in 50 patients, among whom 5 were hoarse on postoperative day 2. However, only one of the patients developed vocal cord palsy. There was no case of right vocal cord palsy in any of our patients. All hoarse patients had paralysis of the abductor muscles. Laryngeal edema was found in 6 hoarse patients after day 2, and 4 patients after day 3. Four of those patients had *abnormal left vocal cord function during indirect laryngoscopy. They all responded to steroid therapy and were asymptomatic at day 5 with return of normal vocal cord function. Table 1. Periopertive Hoarseness in Patients Undergoing Coronary Artery Bypass Surgery HOWSeWZSS
HOC3W3WSS
After Postoperative
After Postoperative
Day 2
Day 3
HOXS?neSS
After Postoperative Day 5
Vocal Cord Paralysis
Female
30
4
0
0
Male
54
46
10
5
79
49
9
4
5
1
1
1
Single mammary dissection Bilateral mammary dissection
264
! ETTERS TO THE EDliGP
Hoarseness following coronary artery bypass surgery is usually attributed to endotrachcal intubation. However. i 1I internal mammary artery dissection, (2) laryngeal edema, or (3) arytenoid cartilage dislocation can account for thtq complication. Any patient with hoarseness lasting for more than 5 days should have indirect laryngoscopy to rule out recurrent laryngeal nerve palsy.
Pieme A. Castheiy, MD Division of Cardiac Anesthesia St Joseph’s Hospital Center Paterson. NJ James Labagnaru, MD Department of Otorhinolaryngology UMDNJ Newark, NJ REFERENCES 1. Pepopard SB, Dickens JH: Laryngeal injury following short-term intubation. Ann Otol Rhino1 Latyngol Y2:317, 1983
2. Phillips T, Green G: Left recurrent laryngeal nerve injury following internal mammary artery bypass. Ann Thorac Surg 43:440, 1987 3. Prasertwanitch Y, Schwartz JJH, Vandam LD: Arytenoid cartilage dislocation following prolonged endotracheal intubation. Anesthesiology 41516, 1974
Continuous
Sedation
of Postoperative
Pediatric Propofol
Cardiac
Surgical
Patients
with
To the Editor: Propofol is a short-acting intravenous anesthetic agent that has been used for total intravenous anesthesia. Recently, long-term infusion of propofol has been introduced to sedate critically ill patients.” We have found only two case reports describing the use of propofol to sedate children4,’ Until now, we have administered propofol postoperatively as a continuous infusion to three pediatric cardiac surgical patients. All three children aged 6 months to 2.5 years had uncomplicated patch closures of ventricular septal defects. Intraoperatively, flunitrazepam and fentanyl were given as anesthetic agents. Postoperatively, controlled mechanical ventilation was continued for 7 to 11 hours. Propofol as a continuous infusion at a dose of 2 to 2.5 mg/kg/h was started on arrival in the intensive care unit. All routine laboratory parameters remained within normal levels. In each case, extubation of the trachea was possible within 10 to 20 minutes after stopping the propofol infusion. In our pediatric patients, propofol provided adequate sedation during the postoperative period of mechanical ventilation. Awakening was rapid after cessation of the propofol infusion in all three patients. Thus, we believe that propofol is an alternative to other agents for sedation of children after surgical repair of acyanotic congenital heart disease.
H. Biihrer, MD P. Stroszczynski, MD J. Motsch, MD Department of Anesthesia University of Heidelberg Heidelberg, Germany
REFERENCES
1. Gottardis M, Khiint-Brady KS, Keller W, et al: Effect of prolonged sedation with propofol on serum triglyceride and cholesterol concentrations. Br J Anaesth 62:393-396,1989 2. Albanese J, Martin C, Lacarelle B, et al: Pharmacokinetics of tong-term propofol infusion used for sedation in ICU patients. Anesthesiology 73:214-217,199O 3. Harper SJ, Buckley PM, Carr K: Propofol and alfentanil
infusions for sedation in intensive therapy. Eur J Anaesthesiol 8:157-165, 1991 4. Taylor DH, Cook JH: Propofol infusion for paediatric sedation. Report of a case and review of the literature. Today’s Anaesthetist 2:121-122, 1987 5. Norreslet J, Wahlgren C: Propofol infusion for sedation of children. Crit Care Med 18:890-892, 1990
LETTERS TO THE EDITOR
nique of limited excursion ventilation. Crit Care Med 19:10861089,199l 4. Bowen TE, Fishback ME, Green DC: Treatment of refractory atelectasis. Ann Torac Surg 18:584-589,1974 5. Sachdeva SP: Treatment of postoperative pulmonary atelecta-
Hoarseness
and Vocal
Cord Paralysis
sis by active inflation of the atelectatic lobe(s) through an endotracheal tube. Acta Anaesth Stand l&65-70,1974 6. Fowler III AA, Scoggins WG, O’Donohue WJ Jr: Positive end-expiratory pressure in the management of lobar atelectasis. Chest 74:497-500, 1978
Following
Coronary
Artery Bypass
Surgery
To the Editor: Hoarseness endotracheal
following intubation
coronary artery bypass surgery (CABG) is a frequent complication and is usually attributed to or to internal jugular vein cannulation. From our experience, it is usually self-limiting and
disappears after the second or third postoperative day. To explore the possible causes and to examine the incidence of this disturbing complication, we performed the following study. This study was approved by the Institutional Review Board for human experimentation. Seven hundred fifty patients, aged 40 to 72 years of age, undergoing elective CABG were studied. There were 340 women and 410 men. Patients with prior history of hoarseness, difficult intubation, prior endotracheal intubation, or prolonged postoperative ventilation were excluded from the study. A 9-mm endotracheal tube was used in all male patients and an g-mm endotracheal tube was used in all female patients. All tracheal intubations were achieved atraumatically, using a 3-Macintosh blade. The endotracheal tube cuffs were inflated with air up to an intracuff pressure of 20 cm H,O (measured with a cufflator designed to measure high-volume low-pressure cuffs). They were mechanically ventilated using a tidal volume sufficient to maintain a PaCO, between 35 to 40 mm Hg during surgery and F,O, of 1. The endotracheal tube used was the “Lo Pro” cuffed tracheal tube with a Murphy eye made by Mallinckrodt Critical Care (Glens Falls, NY). Postoperatively, all patients were mechanically ventilated after 12 to 15 hours, using intermittent mandatory ventilation. Following sternotomy all the patients had dissection of the left internal mammary artery. Fifty patients had bilateral dissection of the internal mammary artery. Theinternal mammary artery was exposed using a Favaloro self-retaining sternal retractor. Once the pleura was divided, the internal mammary artery was isolated from the sixth intercostal space to the level of the first rib using low-voltage electrocoagulation (1.5 to 20 W). The patients were then given heparin, 4 mg/kg, cannulated, and cardiopulmonary bypass begun, during which the patients were cooled down to 27°C (bladder). The heart was protected using cold blood cardioplegia and cold topical irrigating saline solution. (No isolation pad was used.) Myocardial temperature was recorded using the Mon-a-therm myocardial temperature sensor (model 6500; Mon-a-therm Inc, St Louis, MO). All patients were examined daily for hoarseness for 5 days by a critical care nurse who had visited them the day before surgery. They were tested for hoarseness every hour after extubation for 6 hours, then every 8 hours during the first postoperative day. If hoarseness persisted for more than 2 days, an indirect laryngoscopy was performed by an otolaryngologist. Eighty-four patients exhibited hoarseness following removal of the endotracheal tube (Table I). Fifty patients remained hoarse after the third postoperative day and required indirect laryngoscopy. On the fifth postoperative day, only 10 of them were still hoarse, 5 had left vocal cord paralysis and were discharged after the tenth postoperative day. Examination of these five patients 3 weeks postoperatively showed arytenoid movement. Vocal cord function returned to normal by 8 weeks postoperative; none of these patients developed neurological complications (stroke:). Dissection of right and left internal mammary artery was performed in 50 patients, among whom 5 were hoarse on postoperative day 2. However, only one of the patients developed vocal cord palsy. There was no case of right vocal cord palsy in any of our patients. All hoarse patients had paralysis of the abductor muscles. Laryngeal edema was found in 6 hoarse patients after day 2, and 4 patients after day 3. Four of those patients had *abnormal left vocal cord function during indirect laryngoscopy. They all responded to steroid therapy and were asymptomatic at day 5 with return of normal vocal cord function. Table 1. Periopertive Hoarseness in Patients Undergoing Coronary Artery Bypass Surgery HOWSeWZSS
HOC3W3WSS
After Postoperative
After Postoperative
Day 2
Day 3
HOXS?neSS
After Postoperative Day 5
Vocal Cord Paralysis
Female
30
4
0
0
Male
54
46
10
5
79
49
9
4
5
1
1
1
Single mammary dissection Bilateral mammary dissection
264
! ETTERS TO THE EDliGP
Hoarseness following coronary artery bypass surgery is usually attributed to endotrachcal intubation. However. i 1I internal mammary artery dissection, (2) laryngeal edema, or (3) arytenoid cartilage dislocation can account for thtq complication. Any patient with hoarseness lasting for more than 5 days should have indirect laryngoscopy to rule out recurrent laryngeal nerve palsy.
Pieme A. Castheiy, MD Division of Cardiac Anesthesia St Joseph’s Hospital Center Paterson. NJ James Labagnaru, MD Department of Otorhinolaryngology UMDNJ Newark, NJ REFERENCES 1. Pepopard SB, Dickens JH: Laryngeal injury following short-term intubation. Ann Otol Rhino1 Latyngol Y2:317, 1983
2. Phillips T, Green G: Left recurrent laryngeal nerve injury following internal mammary artery bypass. Ann Thorac Surg 43:440, 1987 3. Prasertwanitch Y, Schwartz JJH, Vandam LD: Arytenoid cartilage dislocation following prolonged endotracheal intubation. Anesthesiology 41516, 1974
Continuous
Sedation
of Postoperative
Pediatric Propofol
Cardiac
Surgical
Patients
with
To the Editor: Propofol is a short-acting intravenous anesthetic agent that has been used for total intravenous anesthesia. Recently, long-term infusion of propofol has been introduced to sedate critically ill patients.” We have found only two case reports describing the use of propofol to sedate children4,’ Until now, we have administered propofol postoperatively as a continuous infusion to three pediatric cardiac surgical patients. All three children aged 6 months to 2.5 years had uncomplicated patch closures of ventricular septal defects. Intraoperatively, flunitrazepam and fentanyl were given as anesthetic agents. Postoperatively, controlled mechanical ventilation was continued for 7 to 11 hours. Propofol as a continuous infusion at a dose of 2 to 2.5 mg/kg/h was started on arrival in the intensive care unit. All routine laboratory parameters remained within normal levels. In each case, extubation of the trachea was possible within 10 to 20 minutes after stopping the propofol infusion. In our pediatric patients, propofol provided adequate sedation during the postoperative period of mechanical ventilation. Awakening was rapid after cessation of the propofol infusion in all three patients. Thus, we believe that propofol is an alternative to other agents for sedation of children after surgical repair of acyanotic congenital heart disease.
H. Biihrer, MD P. Stroszczynski, MD J. Motsch, MD Department of Anesthesia University of Heidelberg Heidelberg, Germany
REFERENCES
1. Gottardis M, Khiint-Brady KS, Keller W, et al: Effect of prolonged sedation with propofol on serum triglyceride and cholesterol concentrations. Br J Anaesth 62:393-396,1989 2. Albanese J, Martin C, Lacarelle B, et al: Pharmacokinetics of tong-term propofol infusion used for sedation in ICU patients. Anesthesiology 73:214-217,199O 3. Harper SJ, Buckley PM, Carr K: Propofol and alfentanil
infusions for sedation in intensive therapy. Eur J Anaesthesiol 8:157-165, 1991 4. Taylor DH, Cook JH: Propofol infusion for paediatric sedation. Report of a case and review of the literature. Today’s Anaesthetist 2:121-122, 1987 5. Norreslet J, Wahlgren C: Propofol infusion for sedation of children. Crit Care Med 18:890-892, 1990
