Plus-Hex REFERRAL NURSING
The patient was initially placed on to VCV with a TV of 8 – 10 ml / kg and PEEP was increased to 5 cmH 2
O . A lower TV was used because , in human patients with acute respiratory distress syndrome ( ARDS ), a lower TV is associated with a reduced mortality and a decrease in ventilator days ( Brower , 2001 ). Although this information has not been shown in animals with ARDS , one small study confirmed lower TV are well tolerated in healthy dogs and it may be possible to use lower TV as a protective measure against ventilator-induced injury in patients with ARDS ( Oura et al ., 2012 ). Ideally PCV would be used to prevent any further trauma to the delicate alveoli . However , VCV was chosen due to the poor compliance of the lungs and risk of potentiating hypoventilation .
The first blood gas analysis of the patient indicated a marked hypoxaemia ( PaO 2
34.3 mmHg ) and a relative hypercapnia ( PaCO 2
39.0 mmHg ) for a patient with an increased respiratory rate . Immediately after induction , a second blood gas analysis indicated that , despite FiO 2 of
100 %, the patient was still hypoxaemic ( PaO 2 98.8 mmHg ) and severely hypercapnic ( PaCO 2
88.6 mmHg ), confirming concerns that the patient was on the brink of respiratory failure . After the patient had been ventilated for 1 hour , a repeat arterial sample was taken . This showed improvements in oxygenation ( FiO 2
70 %,
PaO 2
61 mmHg ) and ventilation ( PaCO 2
54.5 mmHg ). During this time , however , the patient continued to have an elevated respiratory rate due to the high ventilatory drive of hypoxaemia and , despite further sedatives being administered , operator control of ventilation was poor .
Following these blood gas results , the decision was made to try pressure-supported SIMV . This results in a set minimum number of breaths being delivered per minute , which are triggered when the patient spontaneously breathes ( Drellich , 2002 ). The patient can breathe spontaneously between the given breaths when desired , as the operator only controls the minimum respiratory rate and minute ventilation ( Hopper & Powell , 2013 ). Pressure support can be used alongside SIMV by allowing the patient to trigger and create the breath , but ensures a preset pressure and thus a pre-set TV is met by supplementing the attempted breath ( Drellich , 2002 ).
The patient continued to improve , with SpO 2 and endtidal carbon dioxide ( EtCO 2
) values improving , and FiO2 was weaned down to 60 % while maintaining oxygen saturation . These values were monitored continually using a multi-parameter monitor unit , and recorded every 5 minutes by the RVN .
The patient was mechanically ventilated for 4 hours . Ideally the patient would have been slowly weaned off the ventilator when the PaO 2 and PaCO 2 were maintained within the normal ranges and ventilatory support could be incrementally decreased without a consequent deterioration in these values . Slowly decreasing the pressure support results in a controlled increase in effort of breathing and indicates that a patient can ventilate and oxygenate sufficiently without support ( Drellich , 2002 ). Unfortunately , in this case , the patient unexpectedly awoke from anaesthesia so ventilation was stopped sooner than the team initially planned . In retrospect , a different maintenance anaesthetic should have been used as it has been shown that patients with more severely diseased lungs require a higher depth of anaesthesia to be comfortable , compared to those with neuromuscular or tracheostomy tubes ( Drellich , 2002 ).
Ventilator care
While the patient was ventilated , nursing interventions were planned and implemented according to the practice ’ s standard operating procedure . This can be split into seven sections : oral care ; airway care ; intravenous catheter care ; eye care ; urinary care ; gastrointestinal care ; and recumbency ( Table 1 ).
Table 1 . Summary of ventilator nursing care , outlining five of the seven sections .
Airway management Oral care Eye care Urinary care
|
Every 4 hours :
• Check cuff , deflate and move slightly before re-inflating
• Suction , if required , using closed system to reduce contamination
Every 24 hours :
• Consider changing endotracheal tube
|
Every 4 hours :
• Clean and reposition SpO 2 probe
• Inspect tongue for ranula formation
• Inspect for ulceration
• Clean and reposition mouth gag , if using
• Cleanse oral cavity with chlorhexidine solution and suction oral cavity
|
Every 2 hours :
• Clean with sterile saline
• Apply lubricant Every 24 hours :
• Examine eye , stain with fluorescein for ulceration
|
Every 4 hours :
• Palpate and express , if short-term ventilation
Place indwelling urinary catheter if ventilating for > 24 hours
|
Recumbency |
|
|
|
Every 4 hours :
• Passive range of motion exercises on limbs
• Turn from lateral > sternal > lateral recumbency
• If sternal must be maintained , turn hips lateral to lateral
• Examine for decubital ulcers
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