This procedure involves the creation of a communication between airway and skin via the cricothyroid membrane. An over-the-needle catheter is then passed through the membrane. This procedure provides a temporary secure airway to oxygenate and ventilate a patient in severe respiratory distress when less invasive measures have failed or are unlikely to be successful.
A high pressure gas source such as Jet Ventilation or percutaneous transtracheal ventilation (PTV) is then used to deliver oxygen to the lungs through the catheter. The gas source attaches to the inserted catheter through an improvised device. One can attach the catheter to a 3-mL syringe with the plunger removed and then attach the syringe to the proximal connection piece of a 7.5-mm internal diameter endotracheal tube (Figure 10-1). Alternatively, one can insert an endotracheal tube into the barrel of the 3-mL syringe and inflate the cuff.
Needle cricothyrotomy is considered preferable in children less than 12 years of age because of the membrane’s small size and close proximity of vascular structures
Advantages over tracheostomy:
Minimal training required
Avoidance of hyperextension of neck
Inability to intubate
Inability to ventilate
Rescue laryngeal mask airway cannot be inserted/passed
Injury to larynx with damage to cricoid cartilage
Relative contraindications include anterior neck swelling that distorts anatomic landmarks, anatomic anomalies that distort the larynx or trachea, and bleeding disorders.
In most cases, the need for securing an airway will outweigh the risks involved in this procedure.
Position patient supine with neck extended, if possible
Identify surface landmarks: thyroid cartilage, cricoid cartilage, and cricothyroid membrane (Figure 10-2)
Clean and sterile drape (universal precautions)
If time, inject 1% lidocaine into the skin, through the cricothyroid membrane and into airway, to anesthetize the airway and suppress the cough reflex
Palpate landmarks; fix thyroid cartilage with the first and third fingers of the nondominant hand, leaving the second finger to locate/palpate the cricothyroid membrane
With the dominant hand, pass a 12- or 14-gauge intravenous cannula attached to a syringe filled with sterile saline through the membrane, angling the needle caudally or inferiorly at 45-degree angle (Figure 10-3)
Apply negative pressure to the syringe; if in the trachea, escaping air should create air bubbles in the syringe
Advance the cannula and remove the needle
Attach Jet ventilator and ventilate at 15 L/min
Monitor adequacy of ventilation by chest wall movement and breath sound auscultation. Can also interpose ETCO2 in the circuit to monitor exhalation
Subcutaneous and mediastinal emphysema
Respiratory acidosis secondary to hypoventilation
Cricothyroidotomy is typically performed as an emergency procedure that is temporizing only:
Ventilation via needle cricothyrotomy is only effective for approximately 45 minutes secondary to inadequate ventilation and CO2 accumulation. This can be particularly injurious to head injury patients, as hypoventilation will lead to intracranial pressure (ICP) increase.
The patient should be intubated (if possible) or formal tracheostomy performed within 24 hours to avoid glottic or subglottic stenosis.
Complete upper airway obstruction proximal to the cricothyrotomy is a contraindication because of the risk of devastating barotrauma to the lungs.
Pericardiocentesis is the aspiration of fluid from the pericardial space that surrounds the heart. It is typically performed in patients experiencing cardiac tamponade and may be lifesaving.
Echocardiography is now the most facile way to identify pericardial effusions, characterize their size and location, and assess dynamic findings associated with tamponade. Hemodynamic effects can be assessed by determining abnormal septal motion, right atrial or right ventricular inversion, and decreased respiratory variation of the inferior vena cava (IVC) diameter.
The presence of life-threatening hemodynamic alterations in a patient with suspected cardiac tamponade.
The aspiration of pericardial fluid in hemodynamically stable patients may be used for diagnostic, palliative, or prophylactic reasons. This procedure should be performed under ultrasonography, fluoroscopic visualization, or computerized tomography.
No absolute contraindications exist in the hemodynamically unstable patient. Even the aspiration of small amounts of fluid may improve the patient’s status and prevent arrest.
Uncorrected bleeding disorders and traumatic cardiac tamponade. Some experts believe that tamponade caused by trauma should be treated via emergency thoracotomy.
Sterile drapes, gown, mask
Small and large syringes
The patient can be positioned either supine or in a semirecumbent position at a 30- to 45-degree angle. This brings the heart closer to the anterior chest wall.
The patient should have at least one intravenous line, should be receiving supplemental oxygen, and should be connected to a cardiac monitor and continuous pulse oximetry. If time permits, placement of a nasogastric tube is advised to decompress the stomach and decrease the chance of gastric perforation.
Identify the anatomic landmarks, including the xiphoid process and the fifth and sixth ribs, and select a site for needle insertion. The subxiphoid approach is most commonly used, followed by the left sternocostal margin. See Figure 10-4.
Sterilely clean and drape the subxiphoid area using universal precautions (if time allows).
Create a skin wheal with local anesthetic solution, and use that wheal to infiltrate and anesthetize subcutaneous and deeper tissue and sternocostal margins.
Connect a large syringe (20 or 60 mL) to the spinal needle, and aspirate 5 mL of normal saline into the syringe. Occasional injection of small amounts of saline can help keep your needle patent and free of clots or debris. If time allows, connect an alligator clip to the base of the spinal needle and connect it to the V1 lead of an electrocardiogram (ECG) machine (see Figure 10-4).
Insert the spinal needle at the subxiphoid area at a 45-degree angle to the abdominal wall and direct toward the left shoulder at 45 degrees off the midline sagittal plane. If time permits, needle insertion should be done under ultrasonographic guidance.
While applying negative pressure on the syringe, slowly advance the needle until there is return of fluid, cardiac pulsations are felt, or there is a change in ECG waveform. If the ECG waveform is consistent with myocardial injury (ST segment elevation), this may mean the needle is in direct contact with the myocardium; slowly withdraw the needle until the tracing returns to normal.