The drug works well and does not cause cardiovascular depression. Ketamine is an anesthetic that may be used as well, but it may cause hallucinations or bizarre behavior upon awakening. Thiopental and methohexital may be used as well to provide sedation, but they tend to cause hypotension. Volume-cycled ventilation
The purpose of mechanical ventilators is to deliver a constant volume, constant pressure, or a combination of both with each breath. Any given volume will correspond to a specific pressure on the pressure-volume curve and vice versa in any case. Settings on each mechanical ventilator may include respiratory rate, tidal volume, trigger sensitivity, flow rate, waveform, and inspiratory/expiratory ratio. The volume-cycled ventilation includes the volume-control function and delivers a set tidal volume. The pressure is not a fixed number but it varies with resistance and capacitance of the respiratory system. The volume-cycled ventilation is the simplest and most efficient of providing ventilation to a patients airway compared to other methods of mechanical ventilation. Each inspiratory effort that is beyond the set sensitivity threshold will be accounted for and fixed to the delivery of the corresponding tidal volume. If the patient does not breathe enough, then the volume-cycled ventilation will initiate a breath for the patient to bring up the breathing rate to the minimum respiratory rate. The synchronized intermittent mandatory ventilation (SIMV) is a similar method of mechanical ventilation that also delivers breaths at a fixed rate and volume that corresponds to the patients breathing.
A hollow tube is used inserted into the trachea to keep the airway open. A tracheal hook is used to keep the space open and prevent retraction. Complications may include hemorrhage, subcutaneous emphysema, pneumomediastinum, and pneumothorax. Cricothyrotomy is used as emergency surgical access due to being fast and simple. Another surgical airway method is called tracheostomy. Tracheostomy is done in the operating room by a surgeon. This is the preferred method for patients requiring long-term ventilation. Tracheostomy uses skin puncture and dilators to insert the tracheostomy tube. Drugs to aid intubation
Patients with respiratory arrest can be intubated without drugs. However, patients can be given sedating and paralytic drugs to minimize discomfort and help out with intubation. Pretreatment includes 100% oxygen, lidocaine, and atropine. 100% oxygen should be administered for 3 to 5 minutes. The time depends on pulse rate, pulmonary function, RBC count, and other metabolic factors. Lidocaine can be given in 1.5 mg/kg IV a few minutes before sedation and paralysis. The purpose of administering lidocaine is to blunt the sympathetic response of an increased heart rate, blood pressure, and intracranial pressure caused by laryngoscopy. Atropine can be given when children produce a vagal response, evidenced by bradycardia, in response to intubation. Some physicians even give out vecuronium, which is a neuromuscular blocker to prevent muscle fasciculations in patients over 4 years old. Fasciculations may result in muscle pain on awakening. Laryngoscopy and intubation are uncomfortable procedures, so etomidate may be delivered. Etomidate is a short-acting IV drug with sedative analgesic properties.