PEDIATRIC ANESTHESIA: Case Report
Severe complications resulting from use of ultrathin bronchoscopes have not been reported. We recently began using a 2.8-mm flexible fiberoptic bronchoscope (#11301, Karl Storz, Tuttlingen, Germany) that contains a separate 1.2-mm channel for suction or oxygen insufflation. We describe a case of life-threatening tension pneumothorax in a neonate associated with the use of this bronchoscope.
A full-term, 2130-gram infant presented on day 2 of life for repair of esophageal atresia and a tracheoesophageal fistula (TEF). There were no other significant abnormalities. The child presented to the operating room breathing room air spontaneously. After anesthetic induction with sevoflurane and oxygen, and while maintaining spontaneous ventilation, direct laryngoscopy was performed. A 3F Fogarty catheter and a 3.0 endotracheal tube (ETT) were easily placed into the trachea, adjacent to one another. The Fogarty catheter would have been placed into the fistula if positive pressure ventilation was required and gastric inflation was occurring. The flexible bronchoscope was then placed through a swivel adapter and into the ETT to visualize the location of the TEF. Copious secretions obstructed the initial attempt to view the TEF, and a second attempt was made while suctioning through the bronchoscope but it was also unsuccessful. It was felt that the 1.2-mm suction channel was too narrow to allow adequate evacuation of secretions. Therefore, oxygen tubing was connected from a flowmeter on the anesthesia machine to the suction channel of the bronchoscope and oxygen was insufflated at 3 L/min. Using short bursts of flow (<1 s) by intermittent occlusion of the channel, the fistula was visualized at a proximal position in the trachea, just below the vocal cords. After approximately 30 s the patient turned purple with noticeable tense expansion of the chest and abdomen. The bronchoscope was immediately removed and positive pressure ventilation was attempted via the ETT, but chest expansion was impossible. The patient’s heart rate decreased to 40 bpm, and chest compressions were begun. A diagnosis of either tension pneumothorax or pneumoperitoneum was entertained. Therefore, 18-gauge IV catheters were placed into the right and left chest cavities (at the midaxillary lines) and into the left upper quadrant of the abdomen. There was an audible release of air after placement of the right chest catheter, after which positive-pressure ventilation was immediately and easily restored and the heart rate increased above 180 bpm. The entire episode lasted approximately 1 min and the oxygen saturation remained above 90%. The ETT tip was placed beyond the level of the fistula. Chest radiography revealed right chest subcutaneous emphysema and pneumomediastinum. Once cardiorespiratory stability was ensured, the surgical team performed a percutaneous gastrostomy, ligation of the TEF, primary repair of the esophageal atresia, and placement of bilateral chest tubes. The patient had no further complications, with tracheal extubation occurring on postoperative day 4 and discharge to home in good condition on day 12 of life.
Different airway management techniques have been described in neonates with TEF (1–5). Our practice is to use flexible bronchoscopy immediately before surgical repair for two reasons. The first is to identify the location of the fistula with potential placement of a Fogarty catheter if the fistula is located distally as a trifurcation at the carina (2,5). Placement of a Fogarty balloon can potentially prevent passage of oxygen into the stomach and prevent gastric distention. The second is to give the surgeon information about the location of the fistula and potential distance between the proximal and distal esophageal segments (6,7). However, the appropriateness of this airway management technique is controversial (8).
Pneumothorax is a complication when oxygen is administered under pressure into the respiratory tract (9–14). Oxygen insufflation through the suction channel of the bronchoscope is used to defog the lens, clear secretions, and increase the fraction of inspired oxygen (15–17). The smaller the cross-sectional area of the ETT, and/or the larger the external diameter of the bronchoscope, the higher will be the resistance to exhalation (18). When air entry exceeds air exit, a sequence of events that consists of lung hyperinflation, tension pneumothorax, pneumomediastinum, and subcutaneous emphysema can occur (19). In a previous report of the use of a Fogarty balloon to occlude a TEF, a rigid bronchoscope was used to localize the fistula, thus avoiding the complication we experienced (2). The most appropriate oxygen flow to be used for insufflation through the flexible bronchoscope is unknown. Oxygen insufflation at any flow is contraindicated when using the bronchoscope inside a relatively small ETT but appears to be safe when introduced into the neonate’s trachea without the presence of an ETT (17). However, there is no safe method when the ETT fits occlusively in the trachea and the bronchoscope fills the lumen of the ETT. If the fiberscope tip becomes completely occluded (e.g., with secretions, or against the tracheal wall), the maximum pressure achievable within the closed system (i.e., the airways distal to the tip of the bronchoscope) is that proximal to the flow regulator (i.e., 45–50 psi) (14).
In summary, we report a case of tension pneumothorax that occurred when oxygen was insufflated through the suction channel of a bronchoscope. Our experience with this case calls into question the need for bronchoscopy before TEF repair. Presently there is no evidence of better outcomes when bronchoscopy is performed.
1. Salem MR, Wong AY, Lin YH, et al. Prevention of gastric distention during anesthesia for newborns with tracheoesophageal fistulas. Anesthesiology 1973; 38: 82–3.
2. Reeves ST, Burt N, Smith CD. Is it time to reevaluate the airway management of tracheoesophageal fistula? Anesth Analg 1995; 81: 866–9.
3. Schwartz N, Eisenkraft JB. Positioning the endotracheal tube in an infant with tracheoesophageal fistula. Anesthesiology 1988; 69: 289–90.
4. Borland LM, Reilly JS, Smith SD. Anesthetic management of tracheal esophageal fistula with distal tracheal stenosis. Anesthesiology 1987; 67: 132–3.
5. Bloch EC, Filston HC. A thin fiberoptic bronchoscope as an aid to occlusion of the fistula in infants with tracheoesophageal fistula. Anesth Analg 1988; 67: 791–3.
6. Kosloske AM, Jewell PF, Cartwright KC. Crucial bronchoscopic findings in esophageal atresia and tracheoesophageal fistula. J Pediatr Surg 1988; 23: 466–70.
7. Benjamin B. Endoscopy in esophageal atresia and tracheoesophageal fistula. Ann Otol Rhinol Laryngol 1981; 90: 376–82.
8. Goudsouzian NG, Ryan JF. Bronchoscopy and occlusion of tracheoesophageal fistula. Anesth Analg 1996; 82: 1308.
9. Chang JL, Bleyaert A, Bedger R. Unilateral pneumothorax following jet ventilation during general anesthesia. Anesthesiology 1980; 53: 244–6.
10. Bar-Joseph G, Bar-Lavie Y, Zonis Z. Tension pneumothorax during apnea testing for the determination of brain death. Anesthesiology 1998; 89: 1250–1.
11. Baraka AS. Tension pneumothorax complicating jet ventilation via a cook airway exchange catheter. Anesthesiology 1999; 91: 557–8.
12. Oliverio R Jr, Ruder CB, Fermon C, Cura A. Pneumothorax secondary to ball-valve obstruction during jet ventilation. Anesthesiology 1979; 51: 255–6.
13. Gallagher MJ, Muller BJ. Tension pneumothorax during pediatric bronchoscopy. Anesthesiology 1981; 55: 685–6.
14. Richardson MG, Dooley JW. Acute facial, cervical, and thoracic subcutaneous emphysema: a complication of fiberoptic laryngoscopy. Anesth Analg 1996; 82: 878–80.
15. Satyanarayana T, Capan L, Ramanathan S, et al. Bronchofiberscopic jet ventilation. Anesth Analg 1980; 59: 350–4.
16. Rosen DA, Rosen KR, Nahrwold ML. Another use for the suction port on the pediatric flexible bronchoscope. Anesthesiology 1986; 65: 116.
17. Dalens B, Labbe A, Haberer JP. Respiratory assistance secured by jet-ventilation during broncho-fiberscopy in forty-nine infants. Anesthesiology 1982; 57: 551–2.
18. Baraka A, Slim M. Cardiac arrest during IPPV in a newborn with tracheoesophageal fistula. Anesthesiology 1970; 32: 564–5.
19. Benumof JL. Airway exchange catheters: simple concept, potentially great danger. Anesthesiology 1999; 91: 342–4.