Principle 3

If the bag-valve mask ventilation does not decrease the patient's work of breathing within minutes and the WOB is still very severe, make sure that the following have been ruled out: 1. Pneumo or hemo or hydrothorax either by auscultation, ultrasound or horizontal beam preferred radiology. 2. Diaphragmatic hernia by same methods. If able to decompress the pleural space conditions with chest aspiration this should be accomplished immediately. In some cases, rapid sequence induction (RSI), will still need to be completed to gain control of the patient to allow decompression to be able to completed with as little stress as possible. In cases of pneumothorax, please keep in mind that by using IPPV we may be making the pneumothorax considerably worse rapidly. In these cases it is imperative to move quickly to decompress the pleural space. If RSI was deemed necessary in this case a simple but very effective means of decompression is to ias is to perform immediate small opening thoracotomy. This can be later converted to chest tube entrance sight or at least a facilitator of the placement of a chest – tube (preferred). This mini-thoracotomy can also be used to collect blood should evidence of a hemothorax is also noted with the chest is entered. Again usually in blunt or penetrating trauma causes of hemothorax the immediate placement of a chest tube and the continued aspiration of the blood from the chest will cause the leaks in the lungs to stop or at least greatly slow down. If after a few minutes it is noted that this is not occurring either a parasternotomy or formal mid-thoracotomy should be performed.

Rapid Sequence Intubation carries some risks to it is imperative that the following be completed in the following steps to avoid complications:

2. Even though the term RSI has the word "rapid" in it the drugs that are given are titrated in to provide the effect needed and it is OK to wait for the drug to take effect and this may be slightly longer than anticipated, especially in cardiovascularly compromised patients.

3. Begin by giving a pain reliever as intubation is painful and also give a parasympatholylitic such as glucopyrolate (preferred) or atropine. I like hydromorphone at 0.05 – 0.1 mg/kg slowly given and then give a hypnotic that will allow intubation. In my experience I like ketamine WITH diazepam because the combination can be fairly safe in the cardiovascularly compromised patient. A one-one volume mixture of these are given, generally slowly at a rate of 0.1 ml/kg (one ml per20 lb body weight). This generally allows gentile and safe intubation and does not drop blood flow as much as Propofol in my experience. Some animals may only require the hydromorphone while others will be so amped up that they will require a bit more ketamine. If they continue to "buck the IPPV provided by the person doing the hand bagging or the anesthetic or ICU ventilator then a muscle blocker is recommended. I prefer atricurium at 0.25 mg/kg body weight and then half doses are repeated as needed. Of course isoflurane can also help but care is given to watch for hypotension or decreased blood flow.

Principle 4

Use a lung protective strategy (LPS) and ventilate for at least several hours to several days depending on arterial blood gases, end tidal CO ₂ levels, spO₂ and radiographic changes. The LPS involves keeping barotraumas and lung shear stresses minimized. This involves aiming for peak inspiratory pressures to be limited to 17-18 cm H₂O, using PEEP at 5-12 cm H₂O, delivering oxygen concentrations below 60 mmHg if at all possible.

Principle 5

Use airway suctioning as required to keep major airways open. Hyper-oxygenate as needed prior to suctioning and if needed perform a tracheostomy to be able to wean off the ventilator more rapidly and still allow good tracheal toileting. IN SOME CASES immediate placement of a tracheostomy for oxygenation and tracheal toileting is recommended. These include the handing of severe inhalation pneumonia and bacterial pneumonia that has been very productive or resistant to common medical management. This allows for a continued decrease in work of breathing because it decreases resistance to airflows, and allows for direct micro-nebulization and humidification.