心包积液胸腔镜的方法（图文演示）

中文版：心包积液胸腔镜的方法（中文图文演示）

THORACOSCOPIC   APPROACH   TO   PERICARDIAL   EFFUSIONS
Authors
D Gossot
Abstract
The description of the Thoracoscopic approach to pericardial effusions covers all aspects of the surgical procedure used for the management of (description de la pathologie en cause).
Operating room set up, position of patient and equipment, instruments used are thoroughly described. The technical key steps of the surgical procedure are presented in a step by step way: Introduction, Anatomy, Indications, Preop period, Operating room set-up, Trocar placement, Instruments, Access/pericardium, Puncture/pericardium, Pericardial opening, Pericardial exploration, Drainage, Complications, Postop period, Reference.
Consequently, this operating technique is well standardized for the management of this condition.

1. Introduction
If pericardial drainage or pericardial biopsy is indicated, the pericardium is approached either by thoracotomy or by subxiphoid abdominal incision. When the patient is in good cardiorespiratory condition, a thoracoscopy is sometimes preferred. This approach allows the creation of a window in the pericardium and a more efficient drainage of pericardial fluid. Thoracoscopy offers a better view than the subxiphoid approach. It is better tolerated than the conventional thoracic approach (Gossot et al., 1994; Nakamoto et al., 2001).

2. Anatomy

[点击按纽展开更多->收起->回放]

The pericardium is a double-layer envelope that surrounds the heart and the origin of large vessels. The 2 layers comprise an external fibrous layer (parietal pericardium) and an internal serosa (visceral pericardium) that enclose a potential cavity between them.
There is often a small quantity of serous fluid (less than 50 mL) between the 2 layers. This liquid is drained by the thoracic duct via the parietal pericardium and the right pleura.
1. Parietal pericardium
2. Visceral pericardium

• Topographic anatomy
• Visceral pericardium
The visceral layer of the pericardium surrounds the heart from its apex to its base, covering the coronary vessels. Cephalad and posteriorly, it extends over the large vessels (aorta and pulmonary artery) and over the pulmonary veins forming 2 vascular sheaths, one for the aorta and the pulmonary artery and another for the pulmonary veins.

[点击按纽展开更多->收起->回放]

The parietal layer of the pericardium may be described as follows:
- laterally: it is separated from the mediastinal pleura by a thin layer of loose cellular tissue that is crossed by the phrenic nerve and the superior phrenic vessels;
- cephalad: it extends over the anterior surface of the large vessels and finally fuses with their tunica adventitia.
1. Esophagus
2. Phrenic nerve
3. Internal thoracic vein
4. Mediastinal pleura
5. Pericardial sac
6. Azygos vein
7. Inferior vena cava
8. Fat pad
9. Aorta

[点击按纽展开更多->收起->回放]

- posteriorly: the elements of the posterior mediastinum, especially the esophagus;
- anteriorly: the fat pads of the pericardium, filling in the cardiophrenic angle, the parietal pleura, the sternum and the thoracic wall;
- caudad: the pericardium lies on the tendinous central part of the diaphragm; they are separated by the phrenico-pericardial ligament.
1. Pericardial sac
2. Internal thoracic vein
3. Right phrenic nerve
4. Inferior vena cava
5. Tendinous diaphragm
6. Aorta and esophagus
7. Left phrenic nerve
8. Fat pad

[点击按纽展开更多->收起->回放]

The pericardium may be approached either from the right or from the left. The view is the same.
However, the left approach is easier because:
- the pericardial surface is wider on the left side than on the right;
- it is usually possible to retract the lung without instruments and to perform the procedure with only 3 trocars. The pericardium may be approached directly through the left interlobar fissure.
1. Middle lobe
2. Muscular diaphragm
3. Phrenic nerve
4. Upper lobe
5. Lower lobe
6. Pericardium
7. Tendinous part of the diaphragm

• Vascular supply
The vascular supply of the visceral pericardium is provided by the coronary arteries. The parietal pericardium is supplied by the phrenic, bronchial and esophageal arteries. Venous drainage takes place via the phrenic and azygos veins.

• Pathophysiology
The pericardium is an envelope with limited expansiveness. Increased intrapericardial pressure owing to the accumulation of fluid has an impact on the heart and induces an increase in intracardiac pressures. This results in a decrease in ventricular preload, of which an extreme manifestation is absent diastolic function. Systolic ejection volume is decreased and pericardial, right atrial, right and left ventricular pressures tend to equalize.
Decrease in systolic ejection volume is first compensated by an increase in sympathetic tone (tachycardia) that helps maintain a constant cardiac output. The subsequent increase in peripheral resistance results in a state of shock.
The deterioration of hemodynamics during pericarditis and tamponade is mainly due to the compression of the right atrium, which impairs venous return. This phenomenon induces a drop in cardiac output.

3. Indications
▶
Indications for surgical drainage of the pericardium
Surgical drainage of the pericardium is indicated in 3 situations:

1. Non-constrictive acute pericarditis, either benign or malignant:
In benign pericarditis: post-traumatic; viral; uremic; post-radiation; tuberculous; purulent.
In viral or uremic pericarditis, a medical treatment (non-steroidal anti-inflammatory drugs, possibly associated with a percutaneous puncture) may be sufficient. Surgery is only indicated in case of failure or diagnostic uncertainty. In purulent pericarditis, a surgical approach is almost always necessary.
In malignant pericarditis: a percutaneous approach is rarely sufficient as recurrence may occur rapidly. Surgical drainage is most often indicated.

2. Constrictive pericarditis:
This necessitates pericardectomy, which is often performed by median sternotomy. In this case, thoracoscopy is not indicated (Hazelrigg et al., 1993).

3. Postoperative pericarditis after cardiac surgery:
This is fairly common, especially after valve replacement surgery in patients on anticoagulants. Repeat surgery by sternotomy carries a significant infectious risk. An endoscopic approach may be interesting in such cases.

Indications of the thoracoscopic approach
- recurrent pericardial effusion that has already been drained by the subxiphoid route;
- previous history of sternotomy;
- biopsy of the pericardium is indicated (the thoracoscopic approach permits larger and more precise biopsies than with the subxiphoid approach);
- indication to explore the pleura simultaneously (concomitant pleural effusion).

Contraindications of the thoracoscopic approach
- previous history of ipsilateral thoracotomy;
- tamponade with hemodynamic instability;
- cardiorespiratory failure;
- selective intubation impossible to perform.

4. Preop period
▶
Assess severity criteria:

Clinical criteria:
- polypnea, orthopnea;
- low blood pressure;
- heart rate >100 beats per minute;
- intolerance to supine position;
- jugular vein distension.
Ultrasonographic criteria:
- circumferential effusion;
- hyperkinetic myocardium (“swinging heart”), or asystoly;
- septal deviation;
- compression of right cavities.

The existence of severity criteria is an indication for emergency surgery. A thoracoscopic approach may be contraindicated. A rapid intervention is preferred (subxiphoid incision). The patient should be placed in supine position, or half-seated. A pericardiocentesis under local anesthesia may be necessary before a definitive procedure.

The following preoperative guidelines should be followed:
- surgeon present in the operating room at the time of anesthetic induction;
- pericardial puncture under local anesthesia in case of hemodynamic instability;
- placement of a venous and arterial catheter;
- continuous cardiac monitoring.

5. Operating room set-up

[点击按纽展开更多->收起->回放]

▶
The procedure is performed under general anesthesia with the lungs deflated by selective intubation or an endobronchial blocker.
When the pericardium is approached from the left, the procedure can be performed without selective ventilation. Yet this method is uncomfortable as the view of the pericardium is generally limited.

[点击按纽展开更多->收起->回放]

▶
- in thoracotomy position, arm hanging down over the table, without a sandbag;
- slightly bent forward to free the posterior surface of the pericardium. In case of massive effusion, the pericardium is very close to the wall, which limits the operative field.

[点击按纽展开更多->收起->回放]

▶
1. Surgeon at the back of the patient
2. Assistant opposite the surgeon
3. Scrub nurse to the surgeon’s left

[点击按纽展开更多->收起->回放]

Two video monitors are placed at the patient’s feet because the surgeon usually views the operating field from a posterior to an anterior position and from cephalad to caudad.

[点击按纽展开更多->收起->回放]

A: the optic instrument is introduced in the fifth left intercostal space, slightly posterior to the mid-axillary line. The introduction of this trocar should be done cautiously as there may be very little space between the wall and the pericardium in case of massive effusion. When the interlobar fissure is free, the introduction of the optic instrument into the fissure offers a direct approach to the pericardium.
B: a 5 mm trocar is introduced in the ninth intercostal space on the posterior axillary line. A grasper is used through this port.
C: a 5 mm trocar is placed on the posterior axillary line in the fifth intercostal space. The scissors are used through this port.
D (optional): a fourth trocar is sometimes necessary to introduce a grasper that helps retract the lower lobe in case of partial or ineffective deflation of the lung. It is introduced on the anterior axillary line in the sixth intercostal space.

[点击按纽展开更多->收起->回放]

1. 0° scope (10 mm)
Three trocars are usually enough:
2. 1 x 10 mm for the scope
3. 2 x 5 mm for the instruments
4. 5 mm suction device
5. 5 mm Metzenbaum type scissors
6. 5 mm grasper
7. 5 mm scalpel with a retractable blade

8. Access/pericardium

[点击按纽展开更多->收起->回放]

Fluid from a potential concomitant pleural effusion is sent for cytologic and bacteriological examination. The effusion is then evacuated.
The pleura is explored and any suspicious lesion is submitted for biopsy.
The pericardium is approached in 2 ways:
If the interlobar fissure separates the 2 lobes completely or almost so, the most direct and simplest approach is to work between the upper and lower lobes.
1. Upper lobe
2. Lower lobe

[点击按纽展开更多->收起->回放]

If the fissure is not complete, the pericardium should be approached caudad to the lower lobe. Then it may be necessary to retract it, especially when the lung is incompletely collapsed. It may be necessary to use a fourth trocar.
The phrenic nerve is identified. This is usually done easily.
1. Diaphragm
2. Phrenic nerve
3. Pericardium
4. Lower lobe

[点击按纽展开更多->收起->回放]

In the presence of an inflammatory or neoplastic pericardium, the phrenic nerve is sometimes difficult to identify.
A probe is introduced through the lower trocar. This helps to explore and identify potential adhesions and to choose a zone that is poorly-vascularized for the incision. The phrenic nerve should remain a landmark throughout the procedure.
1. Lower lobe
2. Diaphragm
3. Pericardium
4. Upper lobe

[点击按纽展开更多->收起->回放]

The pericardium is often under tension, making it impossible to grip with the jaws of a grasper. It should be punctured first. The following instruments may be used:
- coagulating hook (yet the use of monopolar cautery to open the pericardium is contraindicated because of the risk of dysrhythmias);
- sharp scissors;
- endoscopic scalpel with a retractable blade.
Whenever possible, the pericardium is punctured in a non-vascular zone once the phrenic nerve has been identified. The puncture may be performed above or below the nerve. It is easier to create the window below the phrenic nerve. The puncture should be performed cautiously especially when the preoperative echocardiography shows loculations or when effusion is minimal. The puncture helps clear the fluid that may blur the scope when effusion is under pressure. A suction-irrigation cannula is introduced into the puncture site to suck out the residual fluid. The fluid is then processed for cytology and cultures.