Cirugía en la clínica de pequeños animales Cirugía sin sangrado parte 02

 

Cirugía en la clínica de pequeños animales Cirugía sin sangrado parte 01

 

 

a. Increased secretions

(1) Necessitating more frequent suctioning

(2) Loosening of tape

b. Infant activity

c. Procedures requiring repositioning infant

d. Tube slippage

E. Technique (See also Endotracheal

Intubation on the Procedures

Website, and Appendix D for

Techniques of Intubation Specific to

Unique Patient Needs) Orotracheal

Intubation (Table 36.2)

1. Position infant with the head in midline and the neck

slightly extended, pulling chin into a “sniff” position

(Fig. 36.4). The head of the infant should be at operator’s eye level.

It may be helpful to place a roll under the baby’s

shoulders to maintain slight extension of the neck.

2. Put on gloves.

3. Clear oropharynx with gentle suctioning.

4. Empty stomach.

5. Bag-and-mask ventilate and preoxygenate infant as indicated by clinical condition. Follow heart rate and oxygenation.

6. Turn on the laryngoscope light, and hold the laryngoscope in left hand with thumb and first three fingers,

with the blade directed toward patient.

a. Put thumb over flat end of laryngoscope handle.

b. Stabilize the infant’s head with right hand.

The laryngoscope is designed to be held in the

left hand, by both right- and left-handed individuals. If held in the right hand, the closed, curved part

of the blade may block the view of the glottis, as

well as make insertion of the endotracheal tube

impossible.

7. Open infant’s mouth and depress tongue toward the left

with the back of right forefinger (Fig. 36.5).

a. Continue to steady head with third fourth and fifth

fingers of right hand.

b. Do not use the laryngoscope blade to open mouth.

8. Under direct visualization, insert the laryngoscope

blade, sliding over the tongue until the tip of the blade

A B

Fig. 36.3. A: Normal epiglottis obscuring glottis. This amount of clear secretions does not require suctioning for visualization. B: Same airway as in Figure 36.1 after surgical removal of cyst. Glottic opening is

visible just beneath epiglottis. Gentle tracheal, pressure, or decreasing neck extension while lifting tip of

laryngoscope blade, will improve visibility.

Fig. 36.4. Appropriate sniff position for intubation. Note that

the neck is not hyperextended; the roll provides stabilizing

support.

 

A B

Fig. 36.1. A: Vallecula cyst, causing stridor and proximal airway

obstruction. B: Endotracheal tube passes beneath cyst. C: Same

patient after laser surgical treatment.

Table 36.1

Endotracheal Tube Diameter

for Patient Weight and

Gestational Age

Tube Size (ID mm) Weight (g) Gestational Age (wk)

2.5 <1,000 <28

3.0 1,000–2,000 28–34

3.5 2,000–3,000 34–38

4.0 >3,000 >38

238 Section VI ■ Respiratory Care

b. Secure tube carefully in position to avoid dislodgement, kinking, or movement.

(1) Vary contact point from side to side to prevent

damage to developing palate and palatal ridges

(7,8).

(2) Note relationship of head position to intratracheal depth of tube on radiograph (9).

9. Do not leave endotracheal tube unattached from continuous positive airway pressure; the natural expiratory

resistance is lost by bypassing the upper airway.

10. Recognize that in neonates, endotracheal tubes are

often pushed in too far because of the short distance

from the glottis to the carina. Use a standardized graph

or location device (2,5).

11. Recognize the association of a short trachea (fewer than

15 tracheal cartilage rings) with certain syndromes:

DiGeorge syndrome, skeletal dysplasias, brevicollis,

congenital rubella syndrome, interrupted aortic arch,

and other congenital syndromes involving the tracheal

area (10).

Fig. 36.2. Anatomic view of neonatal upper airway. The glottis

sits very close to the base of the tongue, so visualization is easiest

without hyperextending the neck.

Table 36.2 Trouble-Shooting Problems with Endotracheal Intubation

Problem Suggested Approach for Solution

Infant’s tongue gets in way. Push tongue aside with finger before inserting blade.

Secretions prevent visualization. Suction prior to intubation attempt.

Tube seems too big to fit through vocal cords. Verify correct tube size for patient weight and gestational

age.

Vocal cords are closed. Decrease angle of neck extension.

Apply traction to blade.

Apply a short puff of air through the tube onto the vocal

cords.

Select smaller tube size.

Evaluate for airway stenosis.

Unsure of appropriate tube length. Await spontaneous breath.

Apply gentle suprasternal pressure.

Difficult to ventilate after intubation. Insert tube just past vocal cord.

Predetermine tube length.

Obtain chest radiograph with head in neutral position to

confirm tube position relative to carina.

Swelling of neck and anterior chest. Verify that tube is in trachea.

Verify that tube is not in bronchus.

Consider tube and/or airway obstruction.

Consider pulmonary air leak into mediastinum/pericardium (Fig. 38.8A, B)

Blood return from endotracheal tube. Evaluate for tracheal perforation.

Tube slips into main bronchus. Avoid neck hyperextension.

Secure tape fixation.

Maintain correct lip-to-tip distance.

Unplanned extubation. Regularly verify correct tube distance.

Secure tape and replace as necessary.

Support neck when moving infant.

Avoid neck hyperextension or traction on tube.

Secure infant’s hands.

Chapter 36 ■ Endotracheal Intubation 239

12. Identify and prevent the factors that are most likely to

contribute to spontaneous extubation (11).

 

a. Miller blade size 1 for full-term infant

b. Miller blade size 0 for preterm infant (size 00 for

extremely low birth weight infant)

Straight rather than curved blades are preferred

for optimal visualization.

c. Modified blade to allow continuous flow of oxygen

at 1 to 2 L/min for better maintenance of oxygenation during procedure. The use of a Viewmax

(Rusch, Duluth, Georgia) laryngoscope improves

viewing of the larynx but requires a longer time for

tracheal intubation (6).

6. Scissors

7. Oxygen tubing

8. Magill forceps (optional)

Nonsterile

9. Humidified oxygen/air source, blender, and analyzer

10. Resuscitation bag and mask

11. Suctioning device

12. Cardiorespiratory monitor

13. Pulse oximetry oxygen saturation monitor

14. Stethoscope

15. Adhesive tape: Two 8- to 10-cm lengths of 0.5-inch-wide

tape, with half the length split and one 10- to 15-cm

length unsplit

Chapter 36 ■ Endotracheal Intubation 237

D. Precautions (Table 36.2)

1. Select orotracheal route for all emergency intubations

or when a bleeding diathesis is present. Reserve nasotracheal intubation for elective procedures after stabilization with orotracheal tube, unless oral anatomy precludes oral intubation.

2. Prepare all equipment before starting procedure. Keep

equipment ready at bedside of patients likely to require

intubation.

3. Use appropriate-size tubes (Table 36.1). To minimize

upper airway trauma, the tube should not fit tightly

between the vocal cords.

4. To minimize hypoxia, each intubation attempt should

be limited to 20 seconds. Interrupt an unsuccessful

attempt to stabilize the infant with bag-and-mask ventilation. In most cases, an infant can be adequately ventilated by bag and mask, so endotracheal intubation can

be achieved as a controlled procedure. The one important exception is in a case of prenatally diagnosed or

suspected congenital diaphragmatic hernia.

5. Recognize anatomic features of neonatal upper airway

(Fig. 36.2).

6. Ensure visualization of larynx. This is the most important step (Fig. 36.3).

a. Have an assistant maintain proper position of

patient.

b. Avoid hyperextending or rotating neck.

7. Do not use pressure or force that may predispose to

trauma.

a. Avoid using maxilla as fulcrum for laryngoscope

blade.

b. Avoid excessive external tracheal pressure.

c. Avoid pushing tube against any obstruction.

8. Make certain all attachments are secure.

a. Avoid obscuring the point of connection of tube and

adapter with any fixation device.

C

 

Chapter 35 ■ Bubble Nasal Continuous Positive Airway Pressure 235

References

1. Gregory GA, Kitterman JA, Phibbs RH, et al. Treatment of the

idiopathic respiratory distress syndrome with continuous positive

airway pressure. N Engl J Med.1971;384:133.

2. Gregory GA. Devices for applying continuous positive pressure.

In: Thibeault DW, Gregory GA, eds. Neonatal Pulmonary Care.

Menlo Park, CA: Addison-Wesley; 1979.

3. Katwinkel J, Fleming D, Cha CC, et al. A device for administration of continuous positive pressure by the nasal route. Pediatrics.

1973;52:130.

4. Wung JT. Continuous positive airway pressure. In: Wung JT. (ed)

Respiratory care of the newborn: A practical approach. New York:

Columbia University Medical Center; 2009.

5. Aly H. Nasal prongs continuous positive airway pressure: a simple

yet powerful tool. Pediatrics. 2001;108:759.

6. Aly H, Massaro AN, Patel K, et al. Is it safer to intubate premature

infants in the delivery room? Pediatrics. 2005;115:1660.

7. Nowadzky T, Pantoja A, Britton JR. Bubble continuous positive

pressure, a potentially better practice, reducing the use of

mechanical ventilation among very low birth weight infants with

respiratory distress syndrome. Pediatrics. 2009;123:1534.

8. Courtney SE, Kahn DJ, Singh R, et al. Bubble and ventilatorderived nasal continuous positive pressure in premature

infants: work of breathing and gas exchange. J Perinatol. 2011;

31:44.

9. Jobe AH, Kramer BW, Moss TJ, et al. Decreased indicators of

lung injury with continuous positive expiratory pressure in preterm lambs. Pediatr Res. 2002;52:387.

10. Zhang S, Garbutt V, McBride JT. Strain-induced growth of the

immature lung. J Appl Physiol. 1996;81:1471.

11. Lemyre B, Davis PG, dePaoli AG. Nasal intermittent positive

pressure ventilation (NIPPV) versus nasal continuous positive airways pressure (NCPAP) for apnea of prematurity. Cochrane

Database Syst Rev.2002;1:CD002272.

12. Bonner K.M, Mainous R.O. The nursing care of the infant

receiving bubble CPAP therapy. Adv Neonatal Care. 2008;8(2):78.

13. Abdel-Hady H, Shouman B, Aly H. Early weaning from CPAP to

high flow nasal cannula in preterm infants is associated with prolonged oxygen requirement: a randomized controlled trial. Early

Hum Dev. 2011;87:205.

14. Aly H, Massaro AN, Hammad TA, et al. Early nasal continuous

positive airway pressure and necrotizing enterocolitis in preterm

infants. Pediatrics. 2009;124:205.

 

Fig. 35.3. An infant with CPAP properly attached to the head.

(1) Head cap (cap fit well on head covering down to eye brows,

almost entire ears and back of head); (2) breathing circuit tubes

attached to side of hat while avoiding both eyes; (3) three-way

elbow on expiratory limb allows the attachment of pressure

manometer or could be capped to preserve pressure within circuit;

(4) orogastric tube attached to lower lip and chin with Tegaderm;

(5) neck roll allowing slight neck extension (sniff position); (6)

nasal prongs applied to baby—prongs inserted into nares allowing

a space between the transverse arm of the nasal prongs and nose to

avoid damage to nasal columella; (7) supporting chin strip.

Infant should be assessed during the trial for any

tachypnea, retractions, oxygen desaturation, or

apnea. If any of these signs are observed, the trial is

considered failed. Infant should be restarted immediately on CPAP, for at least 24 hours, before

another trial is undertaken.

b. There is no need to change the level of positive pressure during the weaning process. Infant is either on

b-CPAP 5-cm H2O or off CPAP.

c. Do not wean the infant off b-CPAP if there is any

likelihood of respiratory compromise during the

weaning process. It is wise to anticipate and prevent

lung collapse, rather than risk having to manage collapsed lungs.

d. Do not wean infants off b-CPAP if they require supplemental oxygen. (13)

4. Potential Complications

a. Nasal obstruction: From secretions or improper

positioning of b-CPAP prongs. To avoid obstruction,

nares should be suctioned frequently and prongs

checked for proper placement. Never use a nasal–

pharyngeal tube to supply b-CPAP, because of significant risk of nasal airway obstruction.

b. Nasal septal erosion or necrosis: Due to pressure

on the nasal septum. This can be avoided by maintaining a small space (use DuoDERM 2 to

3 mm) between the bridge of the prongs and the

septum. Choosing the proper-sized snug-fitting

nasal prongs, using a Velcro mustache to secure

the prongs in place, and avoiding pinching of the

nasal septum, will minimize the risk of septal

injury. Significant nasal septal erosion may require

consultation with the ENT or Plastic Surgery

team.

c. Gastric distention: From swallowing air. Gastric distention is a benign finding and does not predispose

the infant to necrotizing enterocolitis or bowel perforation (14). It is important to ensure patency of the

indwelling orogastric tube because secretions may

block the tube and lead to distention.

d. Pneumothorax: During the first 2 days of life, premature infants usually will require intubation for this

complication.

e. Unintended increase/decrease in positive end pressure: The tubing that is placed under water to provide positive end pressure must be firmly fixed in

place so that it cannot be displaced to produce

unwanted pressure changes.

Acknowledgement

We thank Aser Kandel, MD for drawing the illustrations in

this chapter.