Page 434 - Clinical Small Animal Internal Medicine

402 Section 5 Critical Care Medicine

while still intubated. During such a “spontaneous breath- without anxiety or fatigue, anesthesia can be discontin-
VetBooks.ir ing trial,” the patient requires frequent, intensive moni- ued and extubation performed.
toring. CPAP is often an ideal mode to use during a
spontaneous breathing trial as the tidal volume, respira-
tory rate, and end‐tidal carbon dioxide can all still be Nursing Care
closely monitored. The development of hypoxemia,
hypercapnia, hyperthermia, tachycardia, hypotension, No chapter on mechanical ventilation would be complete
and/or tachypnea are all indications that the trial has without acknowledging the absolute requirement for
failed. Hypertension and the development of a rapid, skilled, highly trained technicians. Patients receiving IPPV
shallow breathing pattern are common markers used in require continuous monitoring and care. In the authors’
the authors’ practice to identify weaning failure. Positive practice, the patient:nurse ratio for ventilator patients is
pressure ventilation should be reinstituted once weaning always 1:1. Additional nursing staff needs to be available
failure has been identified. as required for turning, airway and oral hygiene, circuit
In human medicine, it is frequently recommended to changes, and many other nursing procedures. Large num-
perform spontaneous breathing trials daily once the bers of highly skilled veterinary technicians are required
patient qualifies according to the criteria listed above. to provide mechanical ventilator support and may be the
When the patient can maintain adequate blood gases single largest determinant of outcomes in many cases.

Further Reading

Acute Respiratory Distress Syndrome Network. Ventilation Hess DR, Kacmarek RM. Essentials of Mechanical
with lower tidal volumes as compared with traditional Ventilation, 2nd edn. New York: McGraw‐Hill, 2002.
tidal volumes for acute lung injury and the acute MacIntyre NR, Branson RD. Mechanical Ventilation,
respiratory distress syndrome. N Engl J Med 2000; 342: 2nd edn. St Louis, MO: Saunders, 2009.
1301–8. Weg JG, Anzueto A, Balk RA, et al. The relation of
Anzueto A, Frutos‐Vivar F, Esteban A, et al. Incidence, risk pneumothorax and other air leaks to mortality in the
factors and outcome of barotraumas in mechanically acute respiratory distress syndrome. N Engl J Med
ventilated patients. Intensive Care Med 2004; 30: 612–19. 1998; 338: 341–6.