Combined anesthesia and early extubation in patient with patent ductus arteriosus: case report

CLINICAL REPORT

Combined anesthesia and early extubation in patient with patent ductus arteriosus. Case report^*

Anestesia combinada e extubação precoce em paciente com persistência do canal arterial. Relato de caso

Anestesia combinada y extubación precoz en paciente con persistencia del canal arterial. Relato de caso

Paulo Antônio de Mattos Gouvêa, TSA, M.D.^I; Cassiano Franco Bernardes, TSA, M.D.^II

^ICo-responsável pelo CET/SBA do Hospital Santa Rita, Anestesiologista do Hospital Infantil e do Hospital e Maternidade Santa Paula, Vitória, ES

^IICo-responsável pelo CET/SBA do Hospital Santa Rita, Anestesiologista da Santa Casa de Misericórdia de Vitória e do Hospital e Maternidade Santa Paula, Vitória, ES

Correspondence

SUMMARY

BACKGROUND AND OBJECTIVES: The ductus arteriosus is a structure of fetal circulation. Prematurity, hypoxia, acidosis and sepsis contribute for patent ductus arteriosus (PDA). This case report aimed at evaluating the use of combined regional/general anesthesia for surgical PDA repair.

CASE REPORT: Male patient, 14 months of age, 11 kg, physical status ASA II, with repeated respiratory infections, was submitted to surgical PDA repair. Patient was premedicated with oral 0.5 mg.kg^-1 midazolam followed by inhalational induction with 1-2% halothane. Hydration consisted of 8 ml.kg^-1.h^-1 lactated Ringer’s. After tracheal intubation, mechanical ventilation was installed with a pediatric closed system with CO₂ absorber. Epidural puncture was performed at T₁-T₂ interspace, followed by a bolus injection of 0.5 ml.kg^-1 of 0.125% bupivacaine with epinephrine 1:800,000. Anesthesia was maintained with halothane (0.5-0.6 CAM). The surgery lasted 70 minutes and was performed by latero-posterior thoracotomy, with good hemodynamic stability. The child was extubated in the operating room and sent to PACU in good conditions.

CONCLUSIONS: Combined regional/general anesthesia in pediatric patients improves peri and postoperative analgesia. Thoracic epidural blockade can be used with good results, if carefully indicated.

Key words: ANESTHESIA, Pediatric; ANESTHETIC TECHNIQUES, Regional: toracic epidural block; SURGERY, Cardiac: patent ductus arteriosus

RESUMO

JUSTIFICATIVA E OBJETIVOS: O canal arterial é uma estrutura que integra a circulação fetal. Fatores como prematuridade, hipóxia, acidose e sepse contribuem para a sua patência. O objetivo deste relato é demonstrar a utilização da anestesia combinada em cirurgia para correção da persistência do canal arterial.

RELATO DO CASO: Paciente masculino, 14 meses, 11 kg, estado físico ASA II com infecções respiratórias de repetição, foi submetido à correção cirúrgica de PCA. Utilizou-se midazolam (0,5 mg.kg^-1) por via oral, no pré-anestésico, seguido de indução inalatória com halotano 1-2%. A hidratação foi feita com solução de Ringer com lactato (8 ml.kg^-1.h^-1). Após intubação orotraqueal foi iniciada ventilação mecânica em sistema circular pediátrico com reabsorvedor de CO₂. Procedeu-se bloqueio peridural torácico no espaço T₁-T₂ com injeção única de bupivacaína a 0,125% com adrenalina 1:800.000 no volume de 0,5 ml.kg^-1. A manutenção foi feita com halotano (0,5-0,6 CAM). O procedimento cirúrgico durou 70 minutos e foi feito por toracotomia látero-posterior com boa estabilidade cardiovascular. A criança foi extubada na sala cirúrgica e encaminhada para SRPA em boas condições.

CONCLUSÕES: A técnica de anestesia combinada em anestesia pediátrica promove melhora na qualidade da analgesia per e pós-operatória. O bloqueio peridural torácico, com indicação criteriosa, pode ser utilizado com bons resultados.

Unitermos: ANESTESIA, Pediátrica; CIRURGIA, Cardíaca: persistência do canal arterial; TÉCNICAS ANESTÉSICAS, Regional: peridural torácica

RESUMEN

JUSTIFICATIVA Y OBJETIVOS: El canal arterial es una estructura que integra la circulación fetal. Factores como prematuridad, hipóxia, acidosis y sepse contribuyen para su patencia. El objetivo de este relato es demostrar la utilización de la anestesia combinada en cirugía para corrección de la persistencia del canal arterial.

RELATO DE CASO: Paciente masculino, 14 meses, 11 kg, estado físico ASA II con infecciones respiratorias de repetición, fue sometido a corrección cirúgica de PCA. Se utilizó midazolam (0,5 mg.kg^-1) por vía oral, en el pré-anestésico, seguido de inducción inhalatoria con halotano 1-2%. La hidratación fue hecha con solución de Ringer con lactato (8 ml.kg^-1.h^-1). Después de intubación orotraqueal fue iniciada ventilación mecánica en sistema circular pediátrico con reabsorvedor de CO₂. Se procedió bloqueo peridural torácico en el espacio T₁-T₂ con inyección única de bupivacaína 0,125% con adrenalina 1:800.000 en el volumen de 0,5 ml.kg^-1. La manutención fue hecha con halotano (0,5-0,6 CAM). El procedimiento cirúrgico duró 70 minutos y fue hecho por toracotomia látero-posterior con buena estabilidad cardiovascular. El niño fue extubado en la sala cirúgica y encaminado para SRPA en buenas condiciones.

CONCLUSIONES: La técnica de anestesia combinada en anestesia pediátrica promueve mejoría en la calidad de la analgesia per y pós-operatoria. El bloqueo peridural torácico, con indicación criteriosa, puede ser utilizado con buenos resultados.

INTRODUCTION

The ductus arteriosus is part of the fetal circulation and consists of a communication of the aorta with the pulmonary artery. After birth, there is a transition to the neonatal circulation and it is functionally closed within the first hours of life due to oxygen blood tension increase and prostaglandins production inhibition. It is anatomically closed before the end of the first month of life. Factors such as prematurity, hypoxia, acidosis and sepsis contribute for its patency ¹. The incidence of this condition is 1:2,500 livebirths, representing approximately 10% of all congenital cardiopathies ^2,3. Ductus arteriosus patency is present especially in premature babies weighting less than 1,000 g (80% of cases), but the need for surgical correction in heavier children is not uncommon ⁴.

The hemodynamic effects of ductus arteriosus patency depend on the additional blood flow to the lungs. When there is an important left-right deviation, there are heart failure, pulmonary hypertension and hyperflow ^1,2-4.

The anesthetic management in more severe cases consists of balanced general anesthesia with high opioids doses and muscle relaxation ^2-4.

This report aimed at showing the feasibility of the combined technique in cases presenting less hemodynamic changes, allowing satisfactory postoperative analgesia with extubation in the operating room.

CASE REPORT

Male, caucasian patient, 14 months of age, 11 kg, with continuous murmur in the left parasternal region, physical status ASA II, with repeated respiratory infections, was submitted to surgical PDA repair.

Monitoring included ECG, non invasive blood pressure, pulse oximetry, capnography and anesthetic gases analysis. Patient was premedicated with oral 0.5 mg.kg^-1 midazolam 40 minutes before surgery. Inhalational anesthesia was induced with 1-2% halothane until the loss of eyelash reflex, followed by right upper limb vein catheterization with a 22G catheter and hydration with 8 ml.kg^-1.h^-1 lactated Ringer’s. Tracheal intubation was performed after 15 mg intravenous lidocaine, followed by mechanical controlled ventilation in a pediatric closed system with CO₂ absorber. With the patient in the right lateral position and after skin cleaning with iodine alcohol, thoracic epidural block was performed at T₁-T₂ interspace.

Puncture was performed in the midline with a 10G Tuohy needle. Epidural space was identified by Dogliotti’s test. A bolus injection of 0.125% bupivacaine with epinephrine 1:800,000 was administered in a total volume of 0.5 ml.kg^-1.

Surgical procedure, which lasted 70 minutes, was performed by latero-posterior thoracotomy with minor bleeding and good hemodynamic stability. Anesthesia was maintained with halothane at 0.5 - 0.6 CAM. Ventilation was changed to manual when pulmonary expansion would impair the surgical field. During pulmonary displacement and ductus arteriosus clamping, hemodynamic parameters kept stable (SBP = 90 mmHg, DBP = 45 mmHg, HR = 96 bpm). There was no need to increase halothane’s concentration. Analgesia was supplemented with 25 mg.kg^-1 intravenous dipirone and 1 mg.kg^-1 rectal dichlophenac. Patient was extubated at the end of the surgery in the operating room, maintaining 97% of hemoglobin saturation while breathing room air. Patient was sent to PACU where he remained without pain and presented fast recovery.

DISCUSSION

There has been an increasing interest during the last decade in the use of central and peripheral regional blocks for peri and postoperative analgesia in pediatric anesthesia⁵, with better anesthetic quality and recovery ^6,7. The use of combined regional and superficial general anesthesia is somewhat arguable. The concern with regional blocks in children under superficial general anesthesia comes from two basic factors: the first one would be the difficulty of detecting local anesthetics intravascular injection; the other is related to a higher theoretic possibility of injuring neurological structures since, being anesthetized, the child would have no means to refer pain or paresthesias which are signs of the contact of the needle with neurological structures ^8,9.

Morbidity studies of regional blocks in children have shown minor complication rates and a good safety margin when performed by qualified professionals and respecting technical details ⁵.

A prospective study of regional anesthesia epidemiology and morbidity in children has shown less use of thoracic epidural block as compared to other neuraxial blockade techniques ⁵.

Caudal anesthesia accounted for 50% of regional blocks. Thoracic epidural block represented 6% of all epidural blocks ⁵. Most epidural blocks are performed in the lumbar region.

Thoracic epidural block is not a routine in children and the anesthesiologist must be well trained in this technique. Puncture must be carefully performed and should only be attempted in children after being proficient in adult epidural puncture ¹⁰.

Low concentration local anesthetics prevent major hemodynamic effects and induce less motor block, which is desirable when early extubation is intended. As with caudal anesthesia, thoracic epidural block provides good hemodynamic stability in children below 8 years of age ^7-10. The technique must bring benefits, such as better control of endocrine-metabolic response to trauma, with lower cortisol and catecholamine plasma levels ⁶.

Indication must be careful. In our specific case, we decided for the thoracic epidural block at T₁-T₂ interspace due to anatomic factors. Spinous processes of thoracic vertebrae are less angulated at this level, making the procedure easier. The child presented with good clinical conditions, which allowed the use of combined anesthesia.

REFERENCES

• 01. Braz JRC, Auler JOC, Amaral JLG et al - O Sistema Cardiovascular e a Anestesia. São Paulo, Editora UNESP, 1996;205-206.
• 02. Lake CL - Pediatric Cardiac Anesthesia. Connecticut, Appleton & Lange, 1993;363-364.
• 03. Hensley FA, Martin DE - A Practical Approach to Cardiac Anesthesia. 2^nd Ed, Boston, Little Brown, 1995; 326-374.
• 04. Motoyama EK, Davis PJ, Smith RM - Anesthesia for Infants and Children. 6^th Ed, St Louis, Mosby 1996; 419-421.
• 05. Giaufre E, Dalens B, Gombert A - Epidemiology and morbidity of regional anesthesia in children: a one year prospective survey of the French-Language Society of Pediatric Anesthesiologists. Anesth Analg, 1996; 83:904-912.
• 06. Liu S, Carpenter R, Neal J - Epidural anesthesia and analgesia: their role in postoperative outcome. Anesthesiology, 1995; 82:1474-1506.
• 07. Tobias JD, Lowe S, ODell N et al - Thoracic epidural anaesthesia in infants and children. Can J Anaesth, 1993;4:879-882.
• 08. Redl G - Regional anesthesia in pediatric surgery. Acta Anaesthesiol Scand, 1998;42 (Suppl):147-149.
• 09. Boltz MG, Krane EJ - Combined regional and light general anesthesia: are the risks increased or minimized? Curr Opin Anesthesiol, 1999;12:321-323.
• 10. Dalens B - Regional Anesthesia in Infants, Children and Adolescents. Maryland, Williams & Wilkins, 1993;249-260.

*

Recebido do Hospital e Maternidade Santa Paula, Vitória, ES

Publication Dates

• Publication in this collection
  21 Mar 2011
• Date of issue
  2001

History

• Received
  28 Nov 2000
• Accepted
  09 Feb 2001