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Procedures 

Procedures
Chapter:
Procedures
Author(s):

Trevor Banack

, Ann Melookaran

, and William Rosenblatt

DOI:
10.1093/med/9780199377275.003.0015
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date: 04 April 2020

Anesthetic Implications of Pacemakers

Although implantation of cardiac pacemakers was originally indicated for symptomatic bradycardia and high-grade atrioventricular block, indications have expanded to include improving cardiac function via synchronized biventricular pacing in patients with dilated cardiomyopathy. Pacemakers can be single chamber (atrial or ventricular) or dual chamber (atrial and ventricular). Leads can be either unipolar or bipolar. Most cardiologists now implant a bipolar lead, which has a smaller distance between the anode and cathode. This decreases the risk of electromagnetic interference.

Pacemakers can be programmed into three modes, asynchronous, single cardiac chamber demand, or dual cardiac chamber sequential demand. In the asynchronous mode, the pacer delivers pulses at preset time intervals and is not affected by intrinsic cardiac activity. Asynchronous mode is preferred to avoid a disruption in pacing if unipolar electrocautery will be used during surgery. In the demand mode, the pacer delivers pulses only when no cardiac complex is sensed in a set amount of time, as may occur with bradycardia. Demand mode is susceptible to possible inhibition caused by electrocautery interference.

The most commonly used pacemaker code is comprised of five letters (Table 15.1). The first letter position represents the cardiac chamber paced (A = atrium, V = ventricle, and D = dual chamber, O = none). The second letter signifies the cardiac chamber sensed (A, V, D, or O). The third letter represents the response (O = none, I = inhibited, T = triggered, or D = dual). The fourth letter includes rate modulation = R. The fifth letter represents anti-dysrhythmia function (A,V, D, or O).

Table 15.1 Generic Pacemaker Code (NBG) NASPE (now known as the Heart Rhythm Society)/BPEG Revised (2002)

Position I

Position II

Position III

Position IV

Position V

O = none

O = none

O = none

O = none

O = none

A = atrium

A = atrium

I = inhibited

R = rate modulation

A = atrium

V = ventricle

V = ventricle

T = triggered

V = ventricle

  • D = dual

  • (A + V)

  • D = dual

  • (A + V)

  • D = dual

  • (T + I)

  • D = dual

  • (A + V)

Source: Reprinted with permission from Bernstein AD, et al. The Revised NASPE/BPEG Generic Code for antibradycardia, adaptive-rate, and multisite pacing. PACE 2002; 25: 260–264.

Before Surgery

  • Determine whether the patient has a pacemaker.

  • Establish whether the device is a pacemaker or an implantable cardiac defibrillator.

  • Determine the device manufacturer: The patient should have a card with the relevant information. If this is unavailable, attempt to contact the patient’s cardiologist or primary care physician. (This is not true anymore.)

  • Determine whether the patient is pacemaker dependent either by patient history, obtaining medical records, or via device interrogation. Pacing spikes on an ECG may not be sufficient to make this diagnosis. (Are pacing spikes seen on a resting ECG?)

  • If time permits, interrogate the pacemaker to determine its settings.

  • In an emergency and the preceding information is not available, an ECG can be performed looking for pacing spikes. A chest x-ray can help determine where and how many chambers are paced.

During Surgery

  • Apply standard physiologic monitors as determined by patient status and ASA Guidelines.

  • If unipolar electrocautery will be used during a surgery on a pacemaker-dependent patient, switch the device to asynchronous mode.

  • If the patient has an ICD, turn off the antitachyarrhythmia function and place defibrillator pads on the patient until the device is reactivated.

  • Placing a magnet on top of the majority of pacemakers will cause the device to revert to asynchronous mode. (Note: Depending upon the manufacturer and programmed settings, the rate may indicate remaining battery life.) Placing a magnet on top of an ICD will deactivate the defibrillator portion but will not change the programmed pacer function. A device representative must be present to reprogram the pacemaker.

  • Removing the magnet should restore pacemaker and ICD functions to their original settings. Interrogate the device after surgery.

  • If pacing is affected by electrocautery and a magnet is not on the patient, place a magnet on top of the pacemaker to convert to asynchronous mode. If unipolar electrocautery must be used, the surgeons should use short bursts of energy on the “cutting” setting whenever possible. The electrocautery return pad should be located as far from the pacemaker as feasible. Surgeons should use bipolar electocautery whenever possible.

  • If a hemodynamically significant tachyarrhythmia develops, defibrillate the patient.

  • Intraoperative myocardial ischemia and high blood levels of local anesthetics may elevate the electrophysiologic capture threshold, causing loss of capture. If this occurs, transcutaneous pacing may be required.

Events associated with pacemaker interference include:

  • Hyperventilation (lowers serum potassium level)

  • Shivering

  • Electrocautery

  • Nerve stimulators

    • Neurophysiologic monitoring

    • Muscle fasiculations

    • Large tidal volumes

    • Magnetic resonance imaging

    • Radiofrequency ablation

    • Electroconvulsive therapy

After Surgery

  • Remove the magnet to restore the baseline pacing mode.

  • Monitor the patient until the device is interrogated.

  • If an ICD was deactivated through a programming change, a defibrillator and pads must be immediately available until this function is restored.

Further Reading

Stone ME, Apinis A. Current perioperative management of the patient with a cardica rhythm management device. Semin Cardiothorac Vasc Anesthes. 2009; 13(1): 31–43.Find this resource:

Awake Intubation

Definition

Awake intubation is the securing of the patient airway prior to the induction of general anesthesia. Intubation with a fiberoptic bronchoscope (FOB) is the most commonly used technique, but any technique can be used to insert an endotracheal tube (ETT) if the patient is properly prepared.

Indications

Consider awake intubation when airway evaluation reveals a potential difficult intubation and one of the following:

  • A potential cannot-ventilate by face mask or supraglottic airway (SGA)

  • A potential aspiration risk

  • A patient who would suffer significant oxyhemoglobin desaturation if the airway cannot be secured rapidly

Contraindications

  • Patient’s inability to cooperate

  • Allergy to local anesthetics

Complications

  • Failed intubation

Equipment Checklist

  • Parenteral antisialogogue (e.g., glycopyrolate 0.2–0.4 mg)

  • A nasal vasoconstriction agent (e.g., oxymatazoline or phenylephrine)

  • Local anesthetic (Lidocaine 2% and 4% solutions or viscous preparations are most commonly used.)

  • Several 5-mL syringes and small-gauge needles (e.g., 25 G) as well as several plastic catheters from large-bore intravenous catheters (needle removed)

  • Cotton pads or swabs

  • Alcohol, chlorhexidine, povidone iodine solution for skin preparation

  • McGill forceps

Technique

Many techniques have been described. Topical and/or invasive blocks can be used as described in the following. The anesthesia provider should limit the total dose of lidocaine to 600 mg.

  • Administer an antisialogogue before any topical blocks are applied to the oral cavity.

  • Consider judicious use of light sedation for the procedure.

Many different sedative agents can be used, but use the least number of individual agents (usually not more than two). Administer sedation in small increments to keep a patient cooperative and responsive. Reversal agents should be readily available. Suitable agents include fentanyl (25 mcg IV incremental doses), midazolam (0.5 mg IV incremental doses), and dexmedetomidine (0.4–0.7 mcg/kg/h IV infusion).

  • The nasal mucosa should be anesthetized if a nasal intubation is planned and there are no contraindications. Administer two sprays of oxymetazoline or phenylephrine solution into each nostril. If not contraindicated by mechanism of injury, spray 50 mg of lidocaine into each nostril using a plastic intravenous catheter and syringe.

  • Anesthetize the pharynx. Hold the tongue with a gauze pad and apply 50 mg of lidocaine to both palatoglossal arches. This can be done by soaking a gauze pad with lidocaine and placing it against the palatoglossal arch.

  • Anesthetize the hypopharynx: Hold the tongue with a gauze pad and apply 100 mg of lidocaine to the back of the tongue using a syringe and a plastic IV catheter. Continue to hold the tongue for several minutes to encourage aspiration of the lidocaine.

Consider a superior laryngeal block: Draw 4mL of lidocaine 2% into a 5-cc syringe with a 25 g needle. Palpate the hyoid bone just cephalad to the thyroid notch. Using the thumb and first finger of one hand, the lateral aspects of the hyoid can be identified bilaterally. Insert the needle just below the most lateral aspect of the hyoid on one side, feeling for resistance of the thyrohyoid membrane. If blood or air can be aspirated, withdraw the needle and reposition. Inject 2 mL of local anesthetic into the membrane. Repeat the block on the contralateral side.

  • Anesthetize the trachea: Identify the cricothyroid membrane approximately 1–1.5 cm below the thyroid notch. Insert a needle attached to a syringe filled with 4 mL of lidocaine 2%–4% through the membrane with constant aspiration until air is easily aspirated. After warning the patient that he or she may cough, inject the lidocaine rapidly into the trachea.

Complications

  • Failure to provide sufficient airway analgesia may result in coughing, regurgitation, and aspiration.

  • Oversedation may cause apnea or airway obstruction.

Special Considerations

Any intubation device, which is used in the asleep patient, may also be used for awake intubation.

  • If a FOB is used, lidocaine can be injected through the working channel to augment tracheal analgesia.

  • If a video laryngoscope is being used, an atomizer can be used to apply lidocaine to the vocal cords.

  • If retrograde intubation is being performed (as described), local anesthetic can be injected during the cricothyroid puncture.

Cricothyroidotomy

Cannula (Needle) Cricothyroidotomy

Indications

  • Cannula (needle) Cricothyroidotomy is a method of minimally invasive access into the airway for the purpose of emergent re-oxygenation.

  • This procedure should only be performed by personnel who have received proper training and have the proper equipment available because this procedure is associated with high complication and failure rates. Clinicians should pursue advanced airway training prior to using this technique.

Contraindications

  • Inability to identify the cricoid-thyroid membrane

  • Transected airway

  • Laryngeal injury

  • Surgical cricothroidotomy is not recommended in patients <12 years of age unless the cricothyroid membrane is clearly identifiable.

Equipment Checklist for Needle Cricothyroidotomy

  • Specialized translaryngeal catheter or 14-gauge IV needle when the patient must be oxygenated but catheters are not available. Standard IV catheters are prone to kinking catheters available from Cook Critical Care, (Bloomington, IN) and VBM (Germany).

  • 10-cc syringe

  • High pressure (20–50 psi) oxygen source with pressure reducing regulator

Procedure

  • Anatomic landmarks: The cricothyroid membrane is one finger-breadth below the thyroid notch. The larynx is immobilized with the left thumb and middle finger. The index finger is then used to identify the thyroid cartilage and the cricothyroid membrane.

Needle Cricothyroidotomy

  • Clean and drape the anterior aspect of neck (if time permits).

  • Palpate the larynx and identify the cricothyroid membrane as described.

  • Stabilize the larynx with the thumb and middle finger.

  • Attach the needle-cannula to a 10-mL syringe (with or without fluid).

  • Puncture the skin and cricothyroid membrane at a 90-degree angle to the plane of the neck while continuously aspirating until air can be aspirated from the larynx.

  • Once air is aspirated, aim the needle-cannula 45 degrees caudad, insert the cannula into the airway, and withdraw the needle.

  • Confirm aspiration of tracheal air.

  • Attach the regulated high-pressure oxygen source and inject oxygen at 20 cm H2O pressure for 1 second. Repeat with an inspiration: expiration ratio of 1:3.

  • Adjust timing and pressure to achieve chest expansion and recoil.

Large-Bore Cricothyroidotomy (Melker)

Percutaneous Large-Bore Cricothyroidotomy

  • Clean and drape the anterior aspect of the neck.

  • Immobilize the trachea with the thumb and middle finger and feel the cricothyroid membrane with the index finger.

  • Make a vertical incision over the cricothyroid membrane—first through the skin and subcutaneous tissue.

  • Attach the included stainless steel needle to a syringe (with or without fluid) and insert it through the cricothyroid membrane into the trachea at a 90-degree angle to the plane of the neck. Aspiration of air confirms that the needle is in the trachea.

  • Aim the needle 45 degrees caudad.

  • Remove the syringe and pass a guide wire through the needle.

  • Ensure that the wire is directed caudad, then remove the needle.

  • Pass the assembled dilator-airway (included in the kit) over the wire and into the airway.

  • Remove the dilator and inflate the airway cuff (if included).

  • Secure the airway to skin and ventilate with a self-inflating bag or the anesthesia machine circuit.

Complications

  • Bleeding from the cricothyroid artery or anterior thyroid vein

  • Barotrauma or pneumothorax caused by jet ventilation

  • Subcutaneous emphysema caused by high-pressure air forced into the subcutaneous space

  • Injury to the posterior wall of the trachea

Special Considerations

  • In a “can-not-ventilate, can-not-intubate” situation, cricothyroidotomy provides a definitive airway more quickly than a tracheostomy.

  • Percutaneous cricothyroidotomy requires prior training and experience.

Double Lumen Endotracheal Tube

Definition

A double lumen endotracheal tube (DLET) can be inserted into either the left or right main stem bronchus in order to selectively ventilate one or both lungs.

Indications

  • Selective one-lung ventilation for procedures including lung resection, surgeries of the thoracic esophagus, spine, descending thoracic aorta, video assisted thoracoscopy, and minimally invasive mitral valve surgery via a thoracotomy.

  • Selective one-lung ventilation in patients who have bullae or a bronchopleural fistula

  • Protection of one lung from the contamination (e.g., blood or infected material) from the opposite lung

  • Unilateral lung lavage

Contraindications

  • Known or anticipated difficult airway

  • Tracheal stenosis or a tracheal stent

  • Rapid sequence intubation is a relative contraindication

Equipment Checklist

  • Average tube sizes for adults: 35 Fr (for women <160 cm), 37 Fr (for women >160 cm), 39 Fr (for men <170 cm), and 41 Fr (for men >170 cm). Each DLT exists for the left main bronchus and right main bronchus. The left DLT is usually used because of ease of placement due to the variable origin of the right upper lobe.

  • Tubes in sizes 28 Fr and 32 Fr are available for pediatric patients.

  • Surgical clamp for either the bronchial or tracheal connector.

  • Pediatric FOB to verify tube position and to examine the bronchi if necessary

  • Lubrication and defogger for the FOB

  • DLT suction catheters

Procedure

  • Evaluate the airway. If the patient may have a difficult airway, consider using a FOB to intubate with a single lumen ETT, switch to a DLT over a tube exchange catheter.

  • If a difficult airway is not anticipated, preoxygenate the patient for 5 minutes prior to induction.

  • After preoxygenation, proceed with induction of general anesthesia.

  • Direct the tip of the DLT anteriorly, then place it through the vocal cords under direct laryngoscopy.

  • After the bronchial cuff is past the vocal cords, remove the DLT stylet.

  • Rotate the DLT 90 degrees either to the right or left depending on the bronchus to be intubated and continue to push the tube distally until resistance is encountered (usually 28–30 cm).

  • Inflate the tracheal cuff and connect the breathing circuit. Auscultate bilater breath sounds and confirm the presence of ETCO2.

  • Insert FOB into the tracheal lumen and identify the carina. If the bronchial cuff is in the desired bronchus inject 1–2 mL of air into the bronchial cuff and verify that it does not herniate above the carina.

  • If the bronchial cuff is not visualized, withdraw the DLT after deflating the tracheal cuff. After the bronchial cuff is observed, inflate the tracheal and bronchial cuffs and again verify the positioning of the bronchial cuff relative to the carina.

Complications

  • Hypoxemia during one lung ventilation. Some patients do not tolerate OLV. This could also be caused by a malpositioned DLT.

  • Trauma, including vocal cord damage, abrasion, laryngitis, and perforation.

  • Inadvertent suturing the of DLT during surgery on a bronchus.

  • If the patient develops hypoxemia, confirm proper location of DLT by FOB. Determine if adequate OLV tidal volumes are being deliver 4–6 mL/kg, adjust accordingly, Supply 100% oxygen. If no improvement is observed, provide CPAP to the nonventilated lung. Positive end-expiratory pressure can be added to the ventilated lung. If these maneuvers do improve oxygenation, inform the surgeon that bilateral ventilation is required.

Special Considerations

  • A double lumen tube (DLT) is preferred in patients with blood or infectious contamination because it permits suctioning of the isolated lung.

  • Verify the position of the DLT after the patient is in the final position to rule out migration of the tube.

Further Reading

Campos JH. Lung isolation techniques for patients with difficult airway. Curr Opin Anaesthesiol. 2010; 23: 12–17.Find this resource:

Femoral Vein Catheter

The femoral vein is the preferred route for central venous cannulation in an emergency because the femoral vessels are easier to find and offer direct access to the central circulation. Catheterization of the femoral vein does not have some of the risks associated with internal jugular and subclavian vein catheterization (e.g., arrhythmias, hemothorax, pneumothorax, phrenic nerve, recurrent laryngeal nerve, thoracic duct injury, cardiac tamponade, and valvular injury).

Indications

  • Inability to obtain peripheral venous access

  • Administration of blood, fluids, and medications in an emergency

  • Central venous pressure monitoring

  • Parenteral nutrition

  • Plasmapheresis

  • Dialysis

  • Insertion of pulmonary artery catheter

  • Insertion of a transvenous pacemaker

  • Venous access in patients with superior vena cava syndrome

Contraindications

  • Adequate peripheral access

  • Patient refusal or uncooperative patient

  • Deep venous thrombosis or IVC filter

  • Abdominal trauma or known IVC trauma

  • Burn, infection, or skin damage at insertion site

Equipment Checklist

  • Sterile prep solution

  • Sterile drapes

  • Sterile gown and gloves

  • Central venous catheter kit

Technique

  • Position the patient supine.

  • Prep the site with chlorhexidine alcohol solution (preferred) or povidone iodine solution.

  • Put on mask, sterile gown, and sterile gloves. Apply a sterile drape to the site.

  • Locate the femoral artery. It is usually 1–2 cm distal to the inguinal ligament and medial to the femoral artery.

  • If the patient is awake, inject local anesthetic (lidocaine 1%) subcutaneously, then infiltrate the deeper tissue. Aspirate prior to injecting to avoid inadvertent intravascular injection.

  • Insert a needle attached to a 10-cc syringe medial to the femoral artery. After the needle has passed through the skin, apply negative pressure to the syringe while advancing in a cranial direction. Venous blood will fill the syringe when the needle enters the femoral vein.

  • Remove the syringe, leaving the needle in the vessel and check for pulsatile (arterial) flow. If a pressure transducer is available, connect it to the needle and verify that a venous pressure and tracing is displayed. In an emergency in which a pressure transducer is not available, aspiration of nonpulsatile, dark blood suggests (but does not confirm) that the needle is in the vein.

  • Insert the guide wire through the needle to a depth of 20 cm. Do not let go of the guide wire.

  • After removing the needle over the wire, use the supplied scalpel make an incision along the wire.

  • If inserting a triple lumen catheter, slide the supplied dilator over the wire through the skin to the same depth at which the needle was advanced.

  • Remove the dilator while leaving the guide wire in place. Advance the catheter over the wire. Slowly remove the wire from the vein, advancing it into the catheter until the end emerges from the distal port. Grasp the end of the wire and slide the triple lumen over the wire and into the femoral vein. Remove the wire and suture the femoral catheter to the skin.

  • If inserting a percutaneous sheath, the dilator and catheter are inserted as one unit. Place sheath/dilator assembly over the wire, withdrawing the wire until it emerges from the dilator. Make a skin incision along the guide wire and slide the sheath and dilator together through the skin. Holding the wire and dilator in one hand, slide the sheath off of the dilator into the femoral vein. Remove the dilator and guide wire as a unit. Secure the catheter to the skin.

Special Considerations

  • Femoral vein catheterization is associated with the highest rate of infection and thrombosis.

  • The anatomic relationship of the femoral vein and artery can be variable. The risk of arterial puncture and hematoma should be considered, with increased risk in the anticoagulated patient, especially an anticoagulated patient.

  • The femoral vein is the preferred route of access during cardiopulmonary resuscitation because it is not necessary to stop chest compressions or discontinue intubation attempts during cannulation.

  • Puncturing the femoral vein above the inguinal ligament may cause a retroperitoneal hematoma.

  • Ultrasound guided femoral catheterization is less likely to result in an arterial puncture and hematoma than are techniques involving the use of anatomic landmarks.

Complications

  • Hematoma

  • Inadvertent arterial catheterization

  • Intra-abdominal injury, such as bowel perforation

  • Retroperitoneal hematoma

  • Infection

  • Femoral nerve injury

  • Air embolism

  • Pseudoaneurysm

  • Femoral artery or venous thrombosis

  • Psoas abscess

  • Hip infection

Intubating Laryngeal Masks

The intubating laryngeal masks (ILM) can be used for ventilation and as a tracheal intubation device. Intubating laryngeal masks are similar to the classic laryngeal mask airway (LMA), but include features that facilitate blind or fiberoptic bronchoscope (FOB) placement of a tracheal tube. The barrel of an ILM has a larger diameter than does a typical supraglottic airway, is often more rigid, and is molded with a fixed or pliable anatomic (right angle) curve. These devices perform well in a can-not-intubate/can-not-ventilate situations.

Indications

  • Difficult intubation, difficult ventilation or both

  • Elective ventilation or tracheal intubation

Contraindications

  • Elective use in the patient at risk for gastric content aspiration

Equipment Checklist

  • Intubating laryngeal mask airway (Teleflex Medical, Research Triangle Park, NC; Ambu, Inc., Glen Burnie; Intersurgical, Liverpool, NY; Mercury Medical, Clearwater, FL). Follow manufacture recommendations for size (e.g., for the Teleflex Fastrach: Size 3 is preferred in children older than 12 years of age, size 4 in adults 50–70 kg, and size 5 in adults 70–100 kg.)

  • Cuffed endotracheal tube for blind intubation: Use a straight, wire-reinforced, beveled tracheal tube with a Teleflex Fastrach. These are distributed by the manufacturer. Any tracheal tube can be used with devices from other manufacturers.

Procedure

  • Intubating laryngeal masks are generally used in anesthetized patients.

  • Check the integrity of the cuff and lubricate the ILM with a water-soluble lubricant.

  • Position the patient supine with the head and neck in neutral position.

  • Hold the device in the left hand while opening the patient’s mouth with the right hand.

  • Insert the ILM with the posterior cuff tip pressed against the palate and pharyngeal wall. When inserting a Teleflex Fastrach, place in the mouth with the handle parallel to the chest wall. Keep the posterior surface against the palate and pharyngeal wall.

  • Continue posterior pressure until resistance occurs and the proximal barrel is parallel with the oral cavity

  • Once the device is in place, inflate the cuff and confirm the position with gentle ventilation of the lungs.

  • Pass the endotracheal tube through the ILM. If using a Teleflex Fastrach tube, the longitudinal black line should be facing cephalad during insertion. This ensures correct bevel orientation.

  • Insert the endotracheal tube 15 cm (to the horizontal black line on Teleflex Fastrach tube) and then advance it another 5 cm.

  • If resistance is encountered, gently lift the ILM anteriorly (the Verghese maneuver) while advancing the ETT into the trachea. This maneuver seals the cup of the LMA against the laryngeal orifice.

  • Once the ETT is in place, inflate its cuff and confirm its position by ventilating the patient and observing for CO2 return.

  • After an emergency intubation, the ILM can be left in situ while expert advice is sought.

Complications

  • The epiglottis may fold as ILM is advanced, occluding the airway. If this occurs, gently withdraw the inflated ILM 6 cm along the access of insertion, and then reintroduce it.

  • Do not inflate the ILM for longer than 15 minutes because it can exert excessive pressure on the surrounding tissues.

Special Considerations

  • Select the appropriate size ILM to ensure correct placement of the device.

  • If the distal end of ILM folds, insert it while it is partially inflated.

  • The ILM is a ventilation and an intubation device. If ventilation is possible with the ILM but intubation is difficult, the clinician should continue ventilation until help arrives.

One Lung Ventilation

Absolute indications for one lung ventilation (OLV) include positive pressure ventilation of one lung in the presence of a bronchopleural fistula or bullae in the contralateral lung and the isolation of one lung from the contamination of blood or infected material from the opposite lung. Relative indications for OLV include lung resection, video-assisted thoracoscopy; surgery of the thoracic esophagus, spine, descending thoracic aorta; and minimally invasive mitral valve surgery via thoracotomy. Bronchial blockers and double lumen tubes are the two devices used most commonly to achieve OLV.

Bronchial Blocker: Definition

A bronchial blocker (BB) device is inserted through a single lumen endotracheal tube after tracheal intubation. One-lung ventilation is achieved by inserting the bronchial blocker into the left or right main stem bronchus and inflating the cuff.

Indications

  • One lung ventilation

  • Known or potential difficult airway

  • Difficulty or inability to place a double lumen tube

  • Pre-existing ETT in situ

  • Patients who are anticipated to require postoperative mechanical ventilation

  • One lung ventilation in patients who have a tracheotomy

  • Selective lobar isolation

Contraindications

  • Patients who are undergoing a lung sleeve resection

  • Pathology (e.g., tumor) in the main stem bronchus

  • Lack of fiberoptic bronchoscope to confirm placement

  • Existing bronchopleural fistula

  • Right lung isolation in a patient in whom the takeoff of right upper lobe is above the carina

Equipment Checklist

  • Minimum size of the ETT should be 7.5 mm; a larger ETT is preferable.

  • Pediatric fiberoptic bronchoscope

  • Lubricant for fiberoptic bronchoscope and bronchial blocker

  • Defogger for fiberoptic bronchoscope

  • Bronchial blocker device

Preparation

  • Evaluate the airway to determine if ventilation or intubation may be difficult.

  • Discuss the use of a bronchial blocker with the surgical team.

  • Confirm that the ETT can accommodate both the bronchial blocker and FOB prior to intubation by placing both into the ETT

Technique

  • Check the bronchial cuff by placing the specified amount of air from the manufacturer. Once cuff integrity is confirmed, remove the air from the cuff.

  • Lubricate both the bronchial blocker and fiberoptic bronchoscope.

  • Intubate the patient with an ETT with an outer diameter of at least 7.5 mm.

  • Insert the FOB into the ETT and identify the region to be isolated.

  • Insert the bronchial blocker into the ETT and advance it until visualized with the fiberoptic bronchoscope.

  • Direct the bronchial blocker into the bronchus or lobe that is to be blocked.

  • Inflate the cuff with the specified volume of air and confirm that the bronchial blocker has not moved.

  • Remove the fiberoptic bronchoscope and open the bronchial blocker lumen to permit the lung to deflate.

Complications

  • Trauma to airway, including bleeding, rupture, pneumothorax, or bronchopleural fistula.

  • Overinflation of the cuff can reduce mucosal blood flow and cause ischemia.

  • Airway occlusion can occur if the bronchial blocker cuff migrates into the carina.

  • Hypoxemia may occur in a patient who is unable to tolerate one-lung ventilation.

Special Considerations

  • Bronchial blockers can easily become dislodged. Verify that the bronchial blocker is in the correct location if the patient is repositioned.

  • Unlike double lumen tubes, bronchial blockers cannot be suctioned.

  • The lumen of the bronchial blocker may become occluded during surgery. If this happens, it can usually be reopened by irrigating with 2–3 cc of normal saline.

Further Reading

Campos JH. Lung isolation techniques for patients with difficult airway. Curr Opin Anaesthesiol. 2010; 23: 12–17.Find this resource:

Campos JH. Update on selective lobar blockade during pulmonary resections. Curr Opin Anaesthesiol. 2009; 22(1): 18–22.Find this resource:

Retrograde Intubation

Definition

An intubation technique in which a guide wire is inserted through the cricothyroid membrane and retrieved from the mouth (or nose). A tracheal tube is then threaded over the guide wire into the trachea.

Indications

  • Retrograde intubation is indicated when conventional techniques for intubation either fail or are not feasible.

  • Unstable cervical spine

  • Excessive secretions or blood in the airway

  • Oropharyngeal malignancy

  • Small mouth opening (direct laryngoscopy and fiberoptic intubation requires that the mouth open 3–4 cm)

  • Failed intubation by other means in an otherwise stable patient

  • Elective intubation of a patient with a known or suspected difficult airway

Contraindications

  • Inability to access the cricothyroid membrane or local infection

  • Coagulopathy

  • Tumor or trauma involving the larynx

  • Retrograde intubation can be time-consuming and should be considered to be an elective procedure.

Equipment Checklist

  • Intravenous catheter or Tuohy needle: The size should be able to accommodate the following wire.

  • Wire: 0.035-inch guide wire (75 cm long: 2–2.5 times the length of a standard endotracheal tube)

  • 5- to 10-mL syringe

  • Magill forceps

  • Endotracheal tube

  • Complete kits are available (e.g., Cook Critical Care). Using a kit ensures that all necessary equipment is available.

Procedure

  • Position the patient supine with the neck slightly extended.

  • If the patient is conscious, prepare as suggested in the section on awake intubation (see page [link]).

  • Clean and drape the anterior part of the neck.

  • Identify the cricothyroid membrane and, if the patient is conscious, infiltrate the skin and subcutaneous tissue over the cricothyroid membrane with 1% lidocaine.

  • Insert the intravenous catheter into the trachea through the cricothyroid membrane. Confirm its position by aspirating air.

  • Direct the catheter cephalad. The 0.035-inch guide wire is threaded through the catheter and retrieved from the mouth. A laryngoscope and Magill forceps may be required to reach the proximal end of the guide wire.

  • Remove the catheter and place a small clamp over the distal end of the guide wire to prevent it from slipping out.

  • Thread the ETT over the proximal end of the guide wire. Maintain tension by gently pulling on both ends of the wire while the ETT is being passed.

  • Remove the guide wire from the cricothyroid membrane and pass the ETT further down into the trachea.

Complications

  • Subcutaneous emphysema

  • Wire travels in a caudad direction, causing coughing

  • Failure to achieve tracheal insertion of the wire

  • Inability to pass the larger endotracheal tube past the entrance of the larynx.

Special Considerations

  • The guide wire can be threaded through the Murphy’s eye of the endotracheal tube to provide better control over the distal end of the endotracheal tube.

  • After the ETT enters the trachea, a soft bougie can be passed before advancing the tube further.

  • If resistance is encountered when passing the ETT, the tube is most likely impinging on the pyriform fossa. Gently rotate the tube while advancing it.

Transcutaneous Pacing

Definition

Cardiac pacing through external cardiac defibrillator pads. Transcutaneous pacing is most commonly used in patients with cardiac rhythm that is causing hemodynamic instability.

Indications

  • Unstable and symptomatic bradycardia

  • Mobitz type II second-degree AV block

  • Third-degree heart block

  • Exchange or repair of an existing permanent pacemaker

  • During re-do cardiac surgery

  • Overdrive pacing in patients with atrial flutter and monomorphic ventricular tachycardia

Contraindication

  • Asymptomatic patients with stable rhythm

  • Hypothermia-induced bradyarrhythmias

Complications

  • Incorrect pacing mode causing tachycardia or atrial or ventricular fibrillation

  • Pain

  • Skin burn

  • Diaphragm irritation

Equipment Checklist

  • Electrocardiogram

  • External pacemaker

  • Defibrillator

  • Pacing pads

Pad Application

  • If the patient has thick hair, shaving may be required prior to pad application.

  • Place the anterior pad at the cardiac apex.

  • Place the posterior pad medial to the right scapula.

Transcutaneous Pacemaker Operation

  • In the conscious patient: Apply the pads as above and connect them to the external pacemaker. Set the current to 0 mA and the heart rate to 80 bpm in the demand (synchronous) mode. (When set to synchronous mode, the pacer only delivers a pulse when no cardiac complex is sensed in a set amount of time.)

  • Increase the output in 10 mA increments until capture is achieved as indicated by a QRS complex after each pacing spike on the ECG. Capture is confirmed by feeling a pulse consistent with the pacing rate.

  • The pacer should be set to deliver 10 mA above the threshold current.

  • In an unconscious patient, set the pacer to the maximum output (200 mA). Decrease the output in 10-mA increments until capture is lost. The final current delivery should be set to 10 mA above threshold.

  • If the pacer does not capture in the synchronous mode, select the asynchronous mode, in which the pacer delivers pulses at at preset time intervals without sensing underlying intrinsic cardiac activity.

Special Considerations

  • Transcutaneous pacing is not recommended for treatment of asystole. Multiple randomized controlled trials showed no improvement in rate of admission to hospital or survival to hospital discharge when transcutaneous pacing was used in the prehospital setting or in the emergency department.

  • It has been reported that a prognosis is poorer when transcutaneous pacing is used for asystole as compared to bradycardia.

Further Reading

Epstein AE, DiMarco JP, Ellenbogen KA, et al. ACC/AHA/HRS 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the ACC/AHA/NASPE 2002 Guideline Update for Implantation of Cardiac Pacemakers and Antiarrhythmia Devices): developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons. Circulation. 2008; 117(21): e350–408.Find this resource:

Rosenthal E, Thomas N, Quinn E, Chamberlain D, Vincent R. Transcutaneous pacing for cardiac emergencies. Pacing Clin Electrophysiol. Dec; 11(12): 2160–2167.Find this resource:

Ryan TJ, Anderson JL, Antman EM, Braniff BA, Brooks NH, Califf RM, Hillis LD, Hiratzka LF, Rapaport E, Riegel BJ, Russell RO, Smith EE III, Weaver WD. ACC/AHA guidelines for the management of patients with acute myocardial infarction: executive summary. Circulation. 1996; 94: 2341–2350.Find this resource:

Transport of a Critically Ill Patient

The intrahospital transport of a critically ill patient carries a significant risk for life-threatening adverse events, including:

  • Hypoxia

  • Severe hypotension or hypertension

  • Arrhythmias

  • Cardiac arrest

  • Agitation

  • Intracranial hypertension

  • Inadvertent extubation

  • Bronchospasm

  • Pneumothorax

  • Medication errors

  • Hemorrhage

  • Equipment failure

Objectives of safe transport include:

  • Stabilization of the patient prior to transport

  • Appropriate level of monitoring (e.g., vital signs, pressure tracings, intracranial pressure)

  • Maintaining consistent ventilator settings prior to and throughout patient movement

  • Communication between the care teams at the points of departure and destination to decrease transport time and minimize the time that the patient away from a critical care environment

  • Provision of sedation to prevent the patient from harming himself or herself by removing ETTs, IVs, chest tubes, drains, or pacer wires

  • Anticipation of and preparation for potential deterioration of the patient’s condition

Transport teams members must be qualified to provide the same level of care as in the ICU, and must be prepared to correct any adverse events. Medications, fluids, a self-inflating bag and mask, airway management supplies, and resuscitation equipment must be immediately available throughout transport.

Equipment Check

  • Transport monitor with capabilities to measure noninvasive blood pressure, arterial and venous waveforms, ECG, and pulse oximetry

  • Transport ventilator with a full oxygen tank

  • Self-inflating bag and mask

  • Airway management equipment; ETTs and stylets, oral airway, laryngoscope and blades, and empty 10-cc syringe

  • Emergency medications for hemodynamic support, sedation, and intubation

  • Intravenous fluids and infusion pumps (if need is anticipated)

  • All electronic equipment, including monitors, infusion pumps, and respiratory equipment, must have sufficient charge for the duration of the transport.

Ready for Transport

  • Begin patient handoff when all required personnel for transport are present.

    • Airway: Confirm that the ETT is secure, suction if necessary, and verify that airway management equipment is ready.

    • Anesthesia: Continue patient sedation during transport. Anticipate the need to increase the level of sedation during transport. If the patient requires neuromuscular blocking agents, these should be administered prior to leaving the room.

    • Breathing: If possible, a respiratory therapist should accompany the patient. Bring a portable ventilator (preset to the patient’s ventilator settings) and a full oxygen tank.

    • Bed: The handoff discussion should include specific patient positioning requirements (e.g., elevated head for intracranial hypertension or flat position for a patient with an unstable cervical spine).

    • Circulation: Confirm that monitoring equipment is functioning properly. Stabilize the blood pressure and heart rate before moving the patient. Bring medications, IV fluids, and check infusion bag volumes to verify sufficient volume for the expected transport duration.

    • Destination: All the team members must know the destination. Confirm that the personnel at the new location are ready to receive the patient.

Transfer of Patient Care in the Intensive Care Unit

  • Place patient on ICU monitors and record the vital signs for the transfer note.

  • Connect patient to the ICU ventilator. Use settings that worked well in the operating room.

  • Administer appropriate medication and fluids, and adjust ventilator settings to stabilize the patient’s vital signs.

  • If the patient is receiving medication infusions (e.g., sedatives, vasoactive drugs), plug the pumps into wall sockets to prevent battery failure.

  • Sign out the patient to the ICU team. Include pertinent intraoperative events (including any adverse events), fluid status, medication administration, including timing of last doses, issues related to airway management, and intraoperative laboratory values.

Further Reading

Fanara B, Manzon C, Barbot O, Desmettre T, Capellier G. Recommendation for the intra-hospital transport of critically ill patients. Crit Care. 2010, 14: R87.Find this resource:

Transvenous Pacing

Definition

Insertion of pacing electrodes through a vein into the right atrium and/or ventricle for treatment of severe symptomatic bradycardia.

Indications

  • Symptomatic bradycardia

  • Mobitz type II second-degree AV block

  • Third-degree heart block

  • Exchange or repair of an existing permanent pacemaker

  • Overdrive pacing in patients with atrial flutter and monomorphic ventricular tachycardia

  • Failure to capture with transcutaneous pacing

  • Temporary electrode insertion after transarterial valve replacement surgery (high incidence of bradycardia and heart block)

Contraindications

  • Hypothermia induced bradyarrhythmias

  • Asymptomatic patients who have a stable cardiac rhythm

Equipment

  • Physiologic monitors, including ECG, blood pressure, and pulse oximetry

  • Advanced cardiac life support medications and supplies

  • Airway management equipment

  • Defibrillator with transcutaneous pads

  • Sterile prep solution, sterile gloves and gown, face mask, and head cover

  • Local anesthetic (e.g., lidocaine 1% solution)

  • Pacer percutaneous sheath introducer kit

  • Pacing leads

  • Suture material

  • Flouroscopy for lead placement location if available

  • External pacer generator

Technique

  • If the patient is conscious, obtain informed consent.

  • Place ECG leads on the patient

  • Refer to Ultrasound Guided Central Venous Access (page [link]) to obtain central venous access for introducer sheath. (The most common venous access sites are the internal jugular or subclavian vein.)

  • Insert a balloon tipped pacing wire through the introducer. When the tip is, in the vein inflate the balloon and connect to the V1 lead of the ECG.

  • Advance the pacing wire while observing the ECG. The waveform will initially display a small P and a larger QRS.

  • As the tip of the wire is advanced into the RA the P wave will be larger than the QRS.

  • When the catheter enters the RV, the P wave decreases in amplitude and the QRS becomes larger. When the tip contacts the RV wall, the V wave amplitude will increase and ST segment elevation may be noted (injury current), indicating proper contact for pacer conduction.

  • Connect the lead to the external generator. If perfusion is compromised, use the highest available current output then decrease slowly until pacing capture is lost. Increase the current to regain capture.

  • If the patient is hemodynamically stable, set the pacer rate to 20 beats above the underlying intrinsic heart rate with a low output. Increase current incrementally until pacer capture is obtained. Current setting should be 2–3× capture threshold.

  • After insertion, obtain a chest X-ray to confirm placement and rule out pneumothorax.

Complications

  • Failure to detect arrhythmias

  • Induction of atrial and ventricular fibrillation and tachycardia

  • Hematoma

  • Pneumothorax

  • Arterial puncture

  • SVC, RA, RV perforation leading to pericardial tamponade

  • Infection

  • Venous air embolism

Special Considerations

  • Transesophageal echocardiography can be used to verify lead position during insertion.

  • Flexible catheters are preferred because they carry less risk of perforation than do stiff catheters.

  • Loss of capture can occur if the lead is displaced. If this happens, increase output to determine whether capture can be regained. Request a chest X-ray to verify lead position.

  • Acidosis, electrolyte abnormalities, hypoxia, and antiarrhythmic medications can increase the capture threshold and cause loss of pacing.

Further Reading

Epstein AE, DiMarco JP, Ellenbogen KA, et al. ACC/AHA/HRS 2008 guidelines for device-based therapy of cardiac rhythm abnormalities: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (writing committee to revise the ACC/AHA/NASPE 2002 guideline update for implantation of cardiac pacemakers and antiarrhythmia devices): developed in collaboration with the American Association for Thoracic Surgery and Society of Thoracic Surgeons. Circulation. 2008; 117(21): e350–408.Find this resource:

Ryan TJ, Anderson JL, Antman EM, Braniff BA, Brooks NH, Califf RM, Hillis LD, Hiratzka LF, Rapaport E, Riegel BJ, Russell RO, Smith EE III, Weaver WD. ACC/AHA guidelines for the management of patients with acute myocardial infarction: executive summary. Circulation. 1996; 94: 2341–2350.Find this resource:

Ultrasound-Guided Central Venous Access

Definition

Use of ultrasonographic imaging to facilitate insertion of a catheter into the external jugular, internal jugular, femoral, or subclavian veins. Ultrasonic guidance also can be used to gain access to central arteries (e.g., the femoral artery), peripheral arteries (e.g., the radial artery) and peripheral veins.

Contraindications

  • Inexperience with ultrasound use

  • Inadequate knowledge of anatomic landmarks and ultrasound structures

Anatomy

  • Arteries appear pulsatile on two-dimensional ultrasound, have a characteristic appearance on color flow Doppler, and cannot be compressed when mild to moderate pressure is applied with the probe.

  • Veins do not appear nonpulsatile on two-dimensional ultrasound (except for the internal jugular veins in patients with severe tricuspid regurgitation), can be compressed when mild pressure is applied with the probe, and distend when there is increased venous pressure (e.g., Trendelenburg position when examining the jugular or subclavian veins veins and during tourniquet application when examining peripheral veins).

Equipment Checklist

  • Ultrasound machine and probes:

Linear transducer probes are useful for smaller sectors and high resolution. Curved transducer probes are useful for scanning a wide field

  • Central line kit, including sterile prep solution and drapes

  • Sterile sheath and ultrasound gel to cover the ultrasound probe

  • Sterile gloves, sterile gown, face mask, and head cover for operator

  • To access a peripheral artery or vein, all of the above supplies except the central line kit. Supplies for peripheral IV or arterial line catheter should be available.

Technique for Right Internal Jugular Central Line Placement

  • Turn the patient’s head to the left <30 degrees if possible.

  • Apply ultrasound gel to the probe and orient to medial and lateral on the probe to the image on the ultrasound monitor.

  • Scan the neck with the ultrasound probe after gel has been applied to identify the carotid and internal jugular veins. The carotid artery in most patients will be located medial to the internal jugular vein.

  • Place the patient into the Trendelenburg position, with the head down 15–25 degrees. (The patient should be secured to the bed or operating room table.)

  • Don a face mask, hat, sterile gloves and gown using standard aseptic technique.

  • Open central line kit using sterile technique.

  • Scrub the neck with sterile prep solution and apply a sterile drape.

  • Open the sterile ultrasound sheath and place gel inside. An assistant should place the probe inside the sheath, leaving the external part sterile.

  • Pull the sheath tight to eliminate air bubbles between the probe and the sheath.

  • Prepare the central line kit.

  • Palpate the carotid pulse and apply ultrasound gel to the skin.

  • Orient the ultrasound probe in the transverse (perpendicular to flow) direction on the neck and identify the carotid and internal jugular vein. Scan the neck caudal and cephalad to find the area where the carotid and internal jugular are separated (or overlap the least), and the internal jugular is largest in diameter.

  • If the patient is awake, infiltrate the skin with 1–2 mL of lidocaine 1%. If the patient is anesthetized, local anesthesia is not necessary.

  • Align the ultrasound probe so that the carotid artery is medial and the internal jugular vein lateral. The internal jugular vein should be aligned with the middle of the probe.

  • Attach a needle or catheter large enough to accommodate a wire to a 5-mL syringe. Place the needle a 45-degree angle in the middle of the transducer probe and press down (without piercing the skin). It should be possible to see an indentation that is aligned with the internal jugular vein.

  • Enter the skin while observing that the trajectory is still aligned with the internal jugular vein. After the needle pierces the skin, apply negative pressure to the syringe. If the needle is seen to approach the artery, pull it back to the skin and direct it in a more lateral direction.

  • As the needle tip approaches the vein, an indentation should be seen on the monitor. Direct eyesight toward the syringe as it is advanced to watch for aspiration of venous blood.

  • Remove the syringe and thread the central line guide wire to a depth of 20 cm. The ultrasound probe should confirm the wire is in the internal jugular vein by both transverse and longitudinal imaging.

  • Remove the needle, make a skin incision in the direction of the wire, and advance the dilator to the same depth as the needle was inserted.

  • Advance the central line over the wire and secure using suture material.

  • Confirm the position with a chest x-ray.

Special Considerations

  • The frequencies used most commonly for catheter insertion are 2–12 MHz.

  • Higher frequencies offer better resolution with decreased depth of penetration.

  • Lower frequencies offer increased depth of penetration with poorer resolution.

Further Reading

Ortega R, Song M, Hansen CJ, Barash P. Ultrasound-guided internal jugular vein cannulation. Videos in clinical medicine. N Engl J Med. 2010; 362: 16.Find this resource: