Implantable Cardioverter-Defibrillator (ICD) Insertion

What Is an ICD?

• A power source (lithium-based battery, lasts 5-10 years; longevity depends on shock frequency)
• Electronic circuitry with storage/remote monitoring capability
• A transvenous lead system (right ventricular lead for sensing, pacing, and shock delivery)

Indications

Class I (Recommended)

1. Survivors of cardiac arrest from VF or hemodynamically unstable sustained VT not due to reversible causes (with >1 year meaningful survival expected)
2. Structural heart disease with spontaneous sustained VT (hemodynamically stable or unstable)
3. Syncope of undetermined origin with inducible sustained VT/VF at electrophysiologic study
4. LVEF <35% due to prior MI - at least 40 days post-MI, 90 days post-revascularization, NYHA class II or III
5. Nonischemic dilated cardiomyopathy with LVEF <35% and NYHA class II or III
6. LV dysfunction post-MI with LVEF <30%, NYHA class I (40 days post-MI, 90 days post-revascularization)
7. Nonsustained VT with prior MI, LVEF <40%, inducible VF/VT at EP study
8. Long QT syndrome with syncope and/or VT while on beta-blockers
9. Catecholaminergic polymorphic VT with syncope/sustained VT on beta-blockers
10. Spontaneous type 1 Brugada pattern with sustained VA or syncope from presumed VA

Class IIa (Reasonable)

• Unexplained syncope + significant LV dysfunction + nonischemic dilated cardiomyopathy
• Sustained VT with normal/near-normal ventricular function
• NYHA class IV patients as bridge to transplant or LVAD (>1 year survival expected)
• Nonischemic cardiomyopathy from Lamin A/C mutation with ≥2 risk factors
• Hypertrophic cardiomyopathy with ≥1 major SCD risk factor
• Arrhythmogenic RV dysplasia/cardiomyopathy with syncope
• Cardiac sarcoidosis, giant-cell myocarditis, or Chagas disease

Class IIb (May Be Considered)

• Nonischemic heart disease, LVEF <35%, NYHA class I
• Long QT syndrome with SCD risk factors
• Syncope + advanced structural heart disease with unexplained cause
• Familial cardiomyopathy associated with sudden death
• LV noncompaction

Class III (Not Indicated)

• Life expectancy <1 year or poor functional status
• Incessant VT/VF (insufficient arrhythmia control)
• Significant psychiatric illness that would preclude follow-up
• NYHA class IV drug-refractory heart failure without transplant/LVAD candidacy
• Syncope in patients with no inducible VT and no structural heart disease

Device Types

The Procedure

Historical Context

• 1970s-80s: Required thoracotomy for epicardial patch placement under general anesthesia with one-lung ventilation
• Modern era: Percutaneous transvenous lead placement has replaced epicardial approaches

Technique

1. Venous access - typically subclavian or cephalic vein (pneumothorax is a recognized complication of subclavian access)
2. Lead placement - RV lead advanced under fluoroscopy to RV apex or septum; RA lead added if dual-chamber
3. Pocket creation - generator placed in subcutaneous or submuscular infraclavicular pocket
4. Device testing - VT/VF is induced; cardioversion/defibrillation thresholds (DFT) are tested; shock strength programmed above minimum required
5. ATP programming - antitachycardia pacing set up for VT zones (interrupts reentry circuit without shock)
6. VF management: device can deliver up to 5 additional shocks if the first shock fails

Anesthesia Options

• Local anesthesia + IV sedation (midazolam + fentanyl)
• Monitoring: pulse oximetry, 5-lead ECG, NIBP
• Deep sedation required for device testing (shocks are painful)

• Preferred in patients with: EF <30%, CHF, CAD, pulmonary hypertension, CKD, valvular disease, or those who cannot lie flat
• Additional monitoring: arterial line may be added
• External defibrillator pads required for all ICD placements (backup if implanted device fails)
• Must be vigilant for complications: MI, stroke, cardiac perforation/tamponade, pneumothorax

Preoperative Evaluation

• EP studies to characterize arrhythmia type
• Optimize CHF/hemodynamic status preoperatively
• Patients often present with EF <30% and may require vasopressors during procedure
• Electrophysiologic studies may define VT morphology and substrate

Complications of Implantation

• Infection (up to 11.7% with repeated instrumentation/device revisions)
• Pneumothorax (subclavian access)
• Cardiac perforation/tamponade
• Pocket hematoma
• Lead dislodgement
• Venous thrombosis

ICD Malfunction (Post-implant)

• Increase/change in shock frequency
• Inappropriate shocks (SVT sensed as VT, oversensing of T waves, noncardiac signals)
• Syncope, near-syncope, dizziness (undersensing of VT/VF)
• "Phantom shock" - sensation without device evidence (~10% of patients; associated with PTSD)

• Magnet application: temporarily disables ATP and defibrillation; switches pacemaker to asynchronous mode (AOO/VOO/DOO)
• Device interrogation to identify cause

Lead Extraction

• Lead fracture, venous/myocardial rupture, tamponade
• Small but real chance of requiring emergent cardiac surgery

Postoperative Care

• Continuous monitoring in PACU (especially in patients with EF <30%)
• Watch for early lead dislodgement and pocket complications
• Remote device monitoring available on most modern ICDs
• Patients should be counseled about activity restrictions and driving limitations per institutional/guideline protocols

Intercostal Drain (ICD) Insertion

Overview

Indications

Key anatomy note: Insertion below the 5th intercostal space risks crossing the pleural recesses and injuring the liver (right side) or spleen (left side).

Anatomy and the "Triangle of Safety"

• Anterior - anterior axillary line / lateral border of pectoralis major
• Posterior - mid-axillary line
• Inferior - above the level of the nipple (5th intercostal space)
• Superior - apex of the axilla

• Avoids the breast tissue
• Avoids the internal mammary artery (which runs ~3 cm lateral to the sternal border)
• Minimizes damage to underlying muscle
• 4th or 5th intercostal space is the target - confirmed by palpating the sternal angle (angle of Louis = articulation of rib II), then counting inferiorly

Equipment

• Sterile drape, gown, gloves, mask
• Local anaesthetic (e.g., lidocaine 1-2%)
• Scalpel (size 15 or 11 blade)
• Large curved artery forceps (Kelly clamp) for blunt dissection
• Chest drain tube (see size guide below)
• Suture (0 or 1-0 silk) - retaining stitch + closing stitch
• Underwater seal drainage system
• Sterile dressing/tape

Pre-procedure Preparation

1. Patient position - Semi-recumbent, arm abducted and placed behind head to open the axillary space
2. Consent - Explain procedure and risks
3. Imaging - Confirm side and level (CXR; ultrasound guidance recommended, especially for effusion/empyema)
4. IV access - Ensure patent; analgesia/sedation as needed
5. Monitoring - SpO2, HR, BP
6. Mark the site before cleaning and draping

Surgical (Blunt Dissection) Technique - Step by Step

1. Anaesthesia

• Infiltrate the skin, subcutaneous tissue, periosteum of the rib, and parietal pleura with local anaesthetic (e.g., 10-20 mL of 1% lidocaine)
• The rib periosteum is extremely sensitive - it must be adequately anaesthetized
• Aspirate as you advance to confirm pleural entry before incising

2. Skin Incision

• Make a 2-3 cm horizontal incision in the chosen intercostal space, at the upper border of the rib below
• Cut only the skin with the scalpel; deeper dissection is blunt

3. Blunt Dissection

• Use a curved artery forceps (Kelly clamp) to blunt dissect through the subcutaneous tissue and muscle layers (serratus anterior and intercostals)
• Advance just over the top of the rib to avoid the neurovascular bundle
• Once through the internal intercostal fascia, open the clamp to enlarge the hole to at least 2 cm

4. Pleural Entry

• Insert a gloved finger through the tract to:
  • Confirm you are in the pleural space
  • Check the lung is not adherent to the chest wall (prevents lung puncture)
  • Clear any clot or adhesions

5. Oblique Tract

• Create an oblique tract so that the skin incision and the pleural hole do not directly overlie each other - this reduces the risk of air entrainment around the tube

6. Tube Insertion

• Clamp the distal end of the chest tube to prevent spillage
• Guide the tube with a finger or over the artery forceps (not trocar, which is no longer recommended due to injury risk)
• Advance until all side holes are 2.5-5 cm inside the chest wall
• Direction of tube:
  • Pneumothorax - aim toward the apex (anterosuperiorly)
  • Haemothorax - aim posteriorly and laterally (dependently)
  • Pleural effusion/empyema - toward the base

7. Secure the Drain

• Retaining stitch - a suture around the tube at the skin to secure it; must not obliterate the drain lumen
• Closing (mattress) suture - a vertical mattress suture inserted alongside for later wound closure:
  • Include for pneumothorax management
  • Omit for empyema (the tract should remain open for drainage, provided pleural adherence is present)
• Cover with an occlusive dressing

8. Connect to Underwater Seal

• Connect immediately to the underwater seal drainage bottle
• Confirm correct placement by:
  • Swinging of fluid in the tubing with respiration (indicates patent connection to pleural space)
  • Bubbling on expiration (if pneumothorax present)
  • Confirm with chest X-ray

Seldinger (Small-Bore) Technique

1. Needle and syringe to enter the pleural space (confirm with fluid/air aspiration)
2. Pass a guidewire through the needle
3. Remove the needle; dilate the tract with sequential dilators
4. Advance the drain over the guidewire
5. Remove the guidewire; connect to drainage system

Needle Decompression (Emergency Temporizing Measure)

• Insert a 14-gauge IV cannula into the 2nd intercostal space, midclavicular line, just above the 3rd rib
• Alternatively: 4th-5th intercostal space, anterior axillary line (shorter distance to pleura)
• Rush of air confirms the diagnosis
• Must be followed immediately by tube thoracostomy
• Avoids the internal mammary vessels (3 cm lateral to the sternal border)

Underwater Seal Drainage

• The bottle acts as a one-way valve - air and fluid exit but cannot re-enter
• The drain tube is submerged 2-3 cm below the water surface
• Suction: 20-30 cm H₂O may be applied if lung fails to re-expand
  • Caution: inserting the drain - not the suction - is the life-saving manoeuvre
  • Suction can worsen an air leak if the lung is fragile
  • Suction can deviate the mediastinum if the lung is reluctant to expand
• Never clamp a bubbling drain - rapid lung collapse or tension pneumothorax can result
  • Exception: immediate life-threatening hemorrhage on drain insertion (clamp and go to OR for emergency thoracotomy)

Post-Procedure Management

• Pneumothorax - when bubbling has stopped for 24 hours on suction (or water seal), lung fully expanded on CXR
• Haemothorax/effusion - when drainage is serous and <200 mL/24 hours
• Do not remove chest tubes from mechanically ventilated patients (risk of new pneumothorax)

• Ask the patient to take a deep breath in and hold (Valsalva/end-inspiration)
• Remove briskly while an assistant ties the closing mattress suture
• Apply an occlusive dressing

Complications

Insertion-Related

Post-Insertion

Special Notes

• Infection risk is slightly higher than for pacemaker insertion; meticulous sterile technique throughout
• Autotransfusion: In massive haemothorax, collect blood in a heparinized autotransfusion device for reinfusion
• Blocked tube: Do not irrigate or use a Fogarty catheter - replace the tube or insert a second one
• Empyema drainage: Omit the closing stitch; the tract should lie open. Small-bore Seldinger drains are now preferred first-line for effusions/empyema alongside fibrinolytics

• Triangle of Safety (green zone) - the preferred site for all chest drain insertions; 5th ICS between the anterior and mid-axillary lines, above the nipple level
• Needle decompression site (red dot) - 2nd ICS midclavicular line, used for emergency tension pneumothorax decompression
• Alternative decompression site (orange) - 4th-5th ICS anterior axillary line, increasingly preferred as the chest wall is thinner here
• Intercostal cross-section inset - shows the neurovascular bundle (VAN - vein, artery, nerve) on the inferior surface of the rib with the correct insertion point just above the upper border of the rib below
• Patient positioning inset - arm raised behind the head to open the axillary space

Subcutaneous Emphysema (Surgical Emphysema)

Definition

Pathophysiology

1. Lung parenchyma / tracheobronchial tree - air leaks through a breach in the parietal pleura and enters the chest wall directly
2. Macklin effect (interstitial emphysema) - air from alveolar rupture dissects back along bronchovascular sheaths into the hilum, then into the mediastinum (pneumomediastinum), then into the extrapleural/subcutaneous spaces
3. External source - gas-producing organisms, penetrating wounds, GI tract perforations, dental air drills

Causes

Thoracic Causes (most common)

Other Causes

Clinical Features

Symptoms

• Neck/facial/chest swelling and tightness
• Voice change (hoarseness if laryngeal air)
• Dysphagia (if severe facial/neck SE)
• Eye closure from periorbital swelling (alarming but benign)
• Rarely: dyspnoea, stridor (if SE contributes to airway compression)

Signs

• Crepitus - the hallmark; a characteristic crackling/crunching sensation on palpation ("snow crunching underfoot" or "Rice Krispies")
• Swelling that does not pit (unlike oedema)
• May extend from chest wall to neck, face, axillae, abdomen, scrotum
• Hamman's sign - mediastinal crunch heard on auscultation with each heartbeat (indicates pneumomediastinum)
• Signs of the underlying cause (absent breath sounds, tracheal deviation, etc.)

Diagnosis

Approach

Step 1: Clinical Assessment (ABCDE)

• Airway: Is there stridor, hoarseness, or difficulty swallowing? Is the airway at risk?
• Breathing: Respiratory rate, SpO₂, breath sounds, tracheal position
• Circulation: HR, BP (tension pneumothorax/haemothorax)
• History: Trauma, recent procedure, cough, vomiting, dental work, ventilator patient?

Step 2: Imaging

Key rule from Tintinalli's: Always presume an underlying pneumothorax in any patient with SE - even if it is not visible on CXR. POCUS is more sensitive than CXR for detecting the pneumothorax.

Red Flags Requiring Urgent Investigation

Management

Immediate Priorities

1. Secure the airway if at risk (stridor, hoarseness, rapidly progressive neck SE)
   • Intubation may become impossible if SE progresses - act early
   • In neck trauma: fibreoptic intubation or surgical airway (tracheostomy) below the level of injury
   • Tracheostomy is the definitive airway in laryngotracheal injury with SE
2. Identify and treat the underlying cause - SE itself is rarely immediately dangerous, but its cause often is

Treat the Underlying Cause

Management of the SE Itself

• Observation - SE resorbs spontaneously over days to weeks as the underlying leak is controlled
• High-flow supplemental oxygen - accelerates resorption by replacing nitrogen with oxygen (which resorbs ~65x faster); use 100% O₂ via non-rebreather mask
• Reassure the patient - periorbital swelling is alarming but benign

• Airway compromise → surgical airway
• Severe discomfort / inability to close eyes
• Compartment syndrome

• Blowhole incisions - small bilateral infraclavicular incisions allowing air to escape
• Drain manipulation - if caused by misplaced ICD side hole, reposition or add suction
• Subcutaneous drains - fenestrated drains placed subcutaneously in severe cases

Specific Notes for Ventilated Patients

• Maintain ICD for the full duration of mechanical ventilation - never remove while ventilated
• If SE develops on the ventilator: place ICD on the affected side without waiting for CXR confirmation
• Reduce ventilator pressures (target Pplat <30 cmH₂O, TV 6 mL/kg IBW)

Summary Algorithm

Subcutaneous Emphysema Detected
        |
        ├── Airway threatened? (stridor, hoarse, neck SE) → SECURE AIRWAY FIRST
        |
        ├── Haemodynamically unstable?
        |       └── Tension PTX → Needle decompression → ICD
        |
        ├── Trauma patient?
        |       ├── POCUS / eFAST
        |       ├── CXR + CT chest
        |       └── PTX → ICD; if massive SE + persistent air leak → bronchoscopy
        |
        ├── Ventilated patient?
        |       ├── ICD on affected side
        |       └── Reduce ventilator pressures
        |
        ├── Post-vomiting + chest pain?
        |       └── Boerhaave → CT + contrast swallow → surgical/endoscopic repair
        |
        ├── Fever + systemic sepsis?
        |       └── Gas gangrene → urgent surgical debridement
        |
        └── SE only, cause treated, mild-moderate
                └── High-flow O₂ + observation → resolves spontaneously