Page 2304 - Cote clinical veterinary advisor dogs and cats 4th

1146 Oxygen Supplementation

○ After bulla flushed clean and completely examinations of the ear canal but are useless to treatment or for ears that have relapsed
within a shorter than expected period.
suctioned, infuse antibiotic medication. for ear-flushing procedures • Make your final assessment of the tympanum
VetBooks.ir ○ Instill topical medication if appropriate. • Greatly improved visualization of the canal from a dry canal to eliminate the visual
○ Suction residual fluid from the canal.
Advantages of video-otoscope:
artifact caused by refraction of light from
due to optics, light, and magnification
○ Recover the patient.
Postprocedure • Can increase client compliance when you your light source.
share images with the client
• Topical +/− systemic corticosteroids to reduce • Allows image documentation for medical SUGGESTED READING
the iatrogenic-induced inflammation. records Angus JC, et al: Uses and indications for video-
• Instruct owners to start treating the ear the • Vastly superior for ear-flush procedures otoscopy in small animal practice. Vet Clin North
next day. • Allows for precise and thus safer placement Am Small Anim Pract 31(4):809-828, 2001.
• Analgesics are paramount to manage post- of instruments for tympanic curettage, AUTHOR: Jeffrey M. Person, DVM
procedural pain and to facilitate treatments biopsy, myringotomy, foreign-body and EDITORS: Leah A. Cohn, DVM, PhD, DACVIM; Mark S.
at home by the owner. polyp removal Thompson, DVM, DABVP
Alternatives and Their Pearls
Relative Merits • Do not scope a painful ear.
Handheld otoscopes are less expensive and • Recommend video-otoscopic flushing sooner
very portable and are adequate for cursory rather than later for ears that are refractory

Oxygen Supplementation Bonus Material
Online

Difficulty level: ♦ • Adapter to fit between red rubber and O 2 preparing for a more sustainable method of
tubing supplementation)
Overview and Goal • Elizabethan collar (e-collar) • Mild to modest increase in O 2 concentration
Oxygen (O 2 ) supplementation aims to increase Other methods may require face mask, oxygen • Well tolerated by most
inspired O 2 content, thereby increasing O 2 tent, oxygen cage, incubator, or other supplies. • Leads to O 2 waste
diffusion to the blood to correct or improve • The O 2 source (hose or tubing) is placed
hypoxemia. Anticipated Time close (1-5 cm) to the patient’s nose/mouth.
Varies with type and duration of required • FIO 2 ≈25%-40%, depending on the O 2
Indications supplementation; flow-by or face mask O 2 flow rate (3-15 L/min) and how close the
• Respiratory distress: increased respiratory rate delivery can begin almost instantly O 2 source is to the patient’s nose/mouth.
or effort, paradoxical breathing, orthopnea Face mask:
• Hypoxemia: cyanosis, PaO 2 ≤ 80 mm Hg, Preparation: Important • Quick and simple way to provide short-term
pulse oximetry (SpO 2 ) reading < 95% Checkpoints O 2 supplementation
• During triage and initial assessment of severe/ • Ensure O 2 source is available (e.g., full tanks) • A mask can increase the FIO 2 to 50%-60%,
critical injury or illness at all times. especially when using high flow rates of
• Be familiar with the setup and maintenance ≈8-12 L/min.
Contraindications of available O 2 cage or incubator. • Anesthetic face mask connected to O 2 source
The only true contraindication is open flame, is held over the patient’s face. Ensure that the
but caution should be used. Possible Complications and nose and mouth are not compressed against
• Nasal O 2 catheters in traumatic brain injury Common Errors to Avoid the wall of the mask because this can have
patients can increase intracranial pressure. • O 2 toxicity can occur if fraction of inspired severe consequences on gas flow through the
• Rapid correction of chronic hypoxemia can O 2 (FIO 2) > 50% for prolonged period. mask and patient ventilation.
alter respiratory drive that has been based on Toxicity can occur in 12 hours with 100% • Some patients resist having a mask placed
hypoxemia rather than normal hypercapnia. O 2 or 18 hours with 80% O 2. on their faces.
○ Actual FIO 2 may not be known, depending • Tight-fitting masks may lead to accumulation
Equipment, Anesthesia on method of supplementation (e.g., FIO 2 of carbon dioxide (CO 2).
Equipment needed depends on method chosen not quantified for flow-by, nasal catheter) • The mask should be removed and flow-by
for supplementation. All require an O 2 source. ○ Room air is 21% FIO 2 ; many hypoxemic O 2 implemented if the patient does not
• O 2 tanks, central O 2 source with outlets, or animals are comfortable with FIO 2 of tolerate it due to high flow rates or CO 2
O 2 generator 40%, but FIO 2 > 40% may be required accumulation.
• A source for humidification of O 2 needed for severely hypoxemic patients. Tents and hoods:
if continued for more than an hour ○ Use the lowest flow rate (nasal catheter) • Commercial O 2 tents can be used for
• Tubing from O 2 source to delivery method or FIO 2 (O 2 cage) to maintain adequate recumbent animals, with the tent placed
(e.g., cage, mask, tent) O 2 saturation (e.g., SpO 2 ≥ 94%). loosely over the animal’s head.
Nasal O 2 catheter: • O 2 tubing is run into a precut hole in the
• Red rubber catheter (5-8 Fr typical) Procedure tent, and flow rates are generally as high as
• Lubricant (lidocaine gel ideal) Flow-by O 2 supplementation: 10-15 L/min.
• Proparacaine drops or lidocaine • Easiest method of providing short-term O 2 • O 2 hoods can be assembled using an e-collar
• Suture material or tissue staples supplementation (e.g., during triage or while and plastic food wrap. The transparent wrap

www.ExpertConsult.com