258 Section VII ■ Tube Replacement

5. While inserting the chest tube, allow some air to remain

within pleural space as protective buffer between lung

and chest wall (6).

a. Use emergency pneumothorax evacuation only if

patient is critically compromised. If emergency evacuation is used, remove air only until vital signs are stable.

b. Position infant so that point of entry is the most elevated area of the chest.

(1) Allows air to rise to provide protective buffer

(2) Direct tip of the chest tube anteriorly, toward

the apex of the thorax.

6. Consider the possibility that a rapid, complete evacuation may cause an abrupt increase in mean arterial

blood pressure and cerebral blood velocity to undesirable, supranormal levels (16).

7. To avoid further compromising ventilation, avoid positioning infant in lateral decubitus position with more

normal lung dependent for any longer than necessary.

C

A B

Fig. 38.3. Sequential radiographs. A: Anteroposterior

radiograph demonstrating a cystic lucency at the left base

behind the heart (arrows) that resembles the artifact caused

by taking a film through the hole in the top of an incubator.

Note also the coarse, irregular lucencies of interstitial emphysema (PIE) in the left lung. B: Lateral film showing the

lucency to be real (arrows) and, in this case, a pneumomediastinum located most probably in the left inferior pulmonary

ligament. C: PIE and air in the pulmonary ligament are often

harbingers of impending pneumothorax, in this case, a tension pneumothorax. Note low position of endotracheal tube.

Chapter 38 ■ Thoracostomy 259

Fig. 38.4. Radiographic artifact of cystic lucency behind the

heart (arrows) caused by taking film through top of incubator. The

lateral film was negative, therefore excluding a cystic pulmonary

lesion or air in the pulmonary ligament.

A B

Fig. 38.5. A: On this anteroposterior supine film, there is a line that parallels the chest wall (arrowheads), which suggests the presence of a pneumothorax. B: This left decubitus film (right side up) confirms this line to be a skin fold, negative for air. When there is a question of potential adventitial air or of

the anatomic location of real adventitial air, a decubitus film with the side in question up is the most

important radiographic study.

8. To prevent laceration of lung parenchyma, avoid

inserting needles beyond parietal pleura for diagnostic or emergency taps. Use a straight clamp perpendicular to the needle shaft to limit depth of penetration (Fig. 38.10).

9. Do not use purse-string suturing of the incision site

because resulting scars tend to pucker (6,17) (see

Fig. 38.9).

10. Recognize that air leaks are likely to persist after initial

evacuation in the presence of continuing lung disease

or positive-pressure ventilation. Air leaks resolve in 50%

of patients within the first 4 days after chest tube placement, and 83% resolve after 7 days (18).

a. Continue to watch for patency of the chest tube

(Fig. 38.11).

b. Verify the correct position of the tube.

c. Modify positive-pressure ventilator patterns to minimize risk of further air leaks (10).

(1) Decrease inspiratory time.

(2) Decrease mean airway pressure.

F. Technique (See also Procedures

Website)

Insertion of Anterior Tube for Pneumothorax

1. Determine location of air collection.

a. Physical examination

Auscultation of the small neonatal chest may be

misleading because the breath sounds normally

are bronchotubular and may be relatively well

transmitted across an air-filled hemithorax. In addition, a shift of the point of maximal cardiac impulse

toward the other side is unusual in the presence of

noncompliant lungs. Physical findings of acute

260 Section VII ■ Tube Replacement

abdominal distention, irritability, and cyanosis

and/or a change in transthoracic impedance suggest an air leak but not its location (19,20).

Supplementary diagnostic procedures are usually

necessary.