Keiji Goto, M.D., Ph.D. Department of Anesthesiology & Intensive Care Medicine Okayama University Graduate School of Medicine

Key Points in Anesthetic Management

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How to introduce anesthesia?
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Use of CPB or ECMO
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Ventilation strategy
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Circulatory management for patients with Primary Pulmonary Hypertension (PPH, IPAH)
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Management of early graft failure

Preoperative Anesthetic Management

- Patient Evaluation -

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Cardiac function
  • echocardiography
  • catheterization
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Respiratory function
  • spirometory
  • arterial blood gas analyses
  • ventilation/blood flow scintigraphy
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Activities of daily living
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Infection　　All available new data and the patient’s condition should be reviewed.

- Preoperative Medication -

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No routine premedication
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Psychological preparation
  • Preoperative visit and interview with patient and family serves as a nonpharmacologic antidote to apprehension.
  • Invasive monitoring prior to induction of anesthesia requires proper planning and patient education.
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Activities of daily living
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Pharmacological preparation
  • Discomfort or exertion during the phase of the initial anesthetic preparation may develop rapidly hypoxia, hypercapnia, or cardiac failure.
There is no routine premedication. Preoperative medication consists of psychological preparation and pharmacological preparation. Premedication should be administered with extreme caution, as any further respiratory compromise could be catastrophic. The need for sedation is also real and should not be ignored. Thus, when possible, small, carefully titrated doses of an anxiolytic can be administered. In patients with PPH, who are usually young, some kind of premedication is necessary because anxiety can further compromise pulmonary vasoconstriction and right ventricular afterload. Psychological preparation is important.

- Continuing Pre-operative Medication & Preparation -

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Bronchodilators
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Chest physiotherapy (patients with copious secretions)
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Anti-arrhythmic drugs
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Anti-hypertensive drugs
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Pulmonary vasodilator
  • Prostacyclin I2 by IV infusion (FLOLAN) or Nitric Oxide (NO) should be maintained until on CPB.
Bronchodilators should use them prior to the OR. Patients with copious secretions should do chest physiotherapy. Patients on anti-arrhythmic or anti-hypertensive medication should continue to take these medications. Of note, Patients on pulmonary vasodilator therapy such as FLORAN or NO should be maintained until on CPB or PCPS to avoid catastrophic increases in PA pressures.

- Monitoring of LTx -

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ECG
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Pulse oximeters
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Capnogram
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Tidal volume, Airway pressure
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Temperature probes ( blood, rectum, surface)
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Arterial lines ( right radial artery & femoral artery)
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Pulmonary artery catheter : PAP, CVP
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Multiplane transesophageal echocardiography (TEE)
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NO & NO2 gas analyzer
Extensive monitoring is essential for the management of patients for LTx because hemodynamic and ventilatory changes can be critical and precipitous.

- Additional equipment for LTx -

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Anesthesia ventilator
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Sophisticated ventilator for differential ventilation
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Fiberoptic bronchoscope
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Cardiopulmonary bypass
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VA (venoarterial) ECMO (extracorporeal membrane oxygenation)
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Infusion pumps
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Body surface warming apparatus

Induction of Anesthesia

- Crisis during Induction of Anesthesia -

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Progressive Hypercapnia or Hypoxia
  • Bronchiectasis
  • Cystic fibrosis
  • Emphysema
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Circulatory collapse　　・Primary pulmonary hypertension（PPH）　　・COPD
Induction of anesthesia should be cautious and gradual.

- Induction & Maintenance for Patient with various diseases except PPH -

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Induction & Maintenance
  • Fentanyl
  • Pancuronium or Vecuronium
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Supplementary use
  • Midazolam
  • Propofol
  • Inhaled Sevoflurane
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Ventilation
  • O2 (+ Air) inhalation

- Induction of Anesthesia in PPH Patient -

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Prophylactic use of inotropes for hypotension before induction
  • Dopamine (5-10 μg/kg/min)
  • Noradrenalin (0.01-0.05 μg/kg/min)
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High-dose Fentanyl
  • Induction： 50- μg/kg,　　　Maintenance： 0.3-1 μg/kg/min
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Pancuronium
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Avoid sedatives
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Ventilation
  • 100% O2 inhalation
  • Hyperventilation
  • NO inhalation
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V-A ECMO

- Endotracheal Intubation -

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General Principal : Left-sided double-lumen endobronchial tube (DLT)
  • When possible, a DLT is changed to a single-lumen tube at the end of the case.
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Patient with copious secretions
  • Single-lumen endotracheal tube
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Pediatric LTx
  • a long uncut endotracheal tube may be advanced into the mainstem bronchus to achieve separation.
Bronchial blocker is rarely used because it is difficult as repeated sequential ventilation is desirable

- Ventilation Strategy before CPB -

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Patient with airway disease require:
  • Increased expiratory phase, to minimize gas trapping
  • Treatment of bronchospasm
  • Constant suctioning of secretions (CF, bronchiectasis)
  • High peak airway pressure to maintain gas exchange
  • Manual Ventilation: need 2 anesthesiolosist
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Patient with pulmonary vascular disease require:
  • avoidance of hypoxemic or hypercapnic episodes in severe PH
  • avoidance of atelectasis and excessive pulmonary distention
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Progressive hypercapnia/acidosis, hypoxia, or arrhythmias may require CPB

Management during CPB

- CPB -

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Advantages
  • Right heart is unloaded (decreased afterload)
  • Provide greater hemodynamic stability
  • Permit easier dissection of the lung and hilum
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Disadvantages
  • Obligate infusion of crystalloid
  • Coagulopathy that accompanies heparinization, Bleeding
  • Platelet dysfunction, Activation of complements, Neutrophil activation, Systemic inflammatory response
may contribute to increased reperfusion injury in transplant allograft.

- Hematologic Considerations -

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Adequate preparation of blood transfusion
  • Massive bleeding can occur
  • Blood from suction pump cannot turn in CPB circuit
  • Packed red blood cells and FFP should be prepared 2-3 times more than general cardiac surgery on CPB
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Optimal hematocrit during LTx is likely approximately 30%
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Risk of dilutional coagulopathy and thrombocytopenia

Management after Implantation

- Complications after implantation of the grafts -

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Ischemia-reperfusion lung injury
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Pulmonary venous or arterial anastomotic obstruction
  • TEE
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Pulmonary Hypertension
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Cardiac failure
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Pulmonary thromboembolism

- Reference Index to induce ECMO after Implantation -

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BP：＜ 50～60 mmHg
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mean PAP：＞ 40 mmHg
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SaO2：＜ 85%
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SvO2：＜ 60%
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pH：＜ 7.1
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C.I.：＜ 2.0L/min/m2

- Hemodynamic Management after Implantation -

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for Pulmonary Hypertension
  • PGE1: 0.01 - 0.05μg/kg/min
  • Nitroglycerine or Nitroprusside
  • 100% O2 inhalation
  • Nitric Oxide (NO) inhalation: 10 - 20 ppm
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for Hypotension
  • Dopamine, Dobutamine
  • Norepinephrine: 0.1 - 0.4μg/kg/min
  • Avoidance of fluid overload and excessive increase in cardiac output
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for Arrhythmias (AF, VT)
  • usually related to acute electrolyte abnormalities

- Electrolytes -

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Acute electrolyte abnormalities cause arrhythmias and should be treated aggressively
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Mg++ infusion of 2-3gm may avoid some arrhythmias
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Ca++
  • frequently given after discontinuing CPB
  • useful in the presence of hypocalcemia, hyperkalemia, and hypotension
  • may potentially worsen reperfusion lung injury
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K+ is released during reperfusion of transplanted lungs

Ischemia-Reperfusion Lung Injury

- Prevention of Ischemia-reperfusion Injury -

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Strict hemodynamic management
  • desirable to keep the patient “dry”
  • However, hypovoremia contributes hemodynamic instability
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NO inhalation → Re-expansion of the grafts → reperfusion
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Avoidance of rapid increase in pulmonary perfusion
  • PA clamp removed over 10 minute period for slow reperfusion
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Avoidance of hyperinflation of the grafts

- Medication for Ischemia-reperfusion Injury -

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Methylprednisolone : 20 mg/kg
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PGE1 : 0.01 - 0.05 μg/kg/min
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Nitroglycerin : 0.1 - 2 μg/kg/min
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Inhaled Nitric oxide (NO) : 10 - 20 ppm
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Diuretics
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Furosemide

- Nitric Oxide -

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Mechanism of Action
  • NO induce vasodilation in vascular endothelial cells
    NO activates Guanyl cyclase and increases cGMP
  • NO is delivered by inhalation, directly to pulmonary alveoli to the pulmonary circulation
  • NO is inactivated locally by hemoglobin, hence there is virtually no systemic effect
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Decrease of PVR
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Improvement of V/Q matching
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NO may inhibit neutrophil adhesion to the endothelial cells and platelet aggregation

Differential Lung Ventilation for one-sided graft failure

- Differential Lung Ventilation -

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Purpose : Correction of uneven distribution of V/Q ratio
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Methods：
  • Double-lumen endobroncheal tube
    Two Ventilators
  • Selective PEEP levels
  • Selective Tidal volumes
  • Positioning
  • Selective NO inhalation

General outline in a patient with IIP (on December 4th, 2006)

- Admission to the theater -

Monitor (ECG; 5 leads), SpO2 (right and left hand)
Intravenous line（18G）
Arterial pressure line（22Ｇ）
Secure of right femoral artery and vein (for ECMO)
Triple lumen central venous line (right jugular vein)

- Induction of anesthesia -

Starting the infusion of Noradrenalin and Dopamine
Mask ventilation with Oxygen and NO
Intubation（double-Lumen tube, 37Fr left）
Trans-esophageal echo (TEE)
Pulmonary artery catheter（left jugular vein）
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Induction
□ Fentanyl 60ml
□ Pancronium 8mg
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Maintenance
□ Continuous fentanyl (30ml/hr)
□ Continuous Midazolam (4mg/hr)
□ Continuous Vecronium (5mg/hr)
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The dose was adjusted as required

- Induction of anesthesia -

CPB on (33-34℃)
Removal of right lung（Artery→Vein→Bronchus）
Removal of left lung（Artery→Vein→Bronchus）
Rinse the oral cavity.（isodine）
Rinse the thorax（Saline500ml＋Tobramycin 60mg）
Transplantation of right lung（Bronchus→Vein→Artery）
Transplantation of left lung（Bronchus→Vein→Artery）
Transplantation of right lung（Bronchus→Vein→Artery）
Reventilation of right lung
Reperfusion of right lung
Reventilation of left lung
Reperfusion of left lung

- (weaning from CPB) -

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Preparation for reperfusion
□ PGE1(start 30min before reperfusion)
□ NO (10-20ppm)
□ nitroglycerin 0.5 μg/kg/min
□ methylprednisolone１ｇ(just before reperfusion)
□ Preparation of blood products
□ Dopamine 5γ
□ Dobutamine, Noradrenalin, PD III inhibitors as required

- Pump Off -

Evaluation of PV flow and LV function by TEE

- Post operation -

Observation of the anastomosis of bronchus by optical fiber (Suctioning sputum)
Intubation (Single lumen tube)
Insertion of duodenal tube (through the fluoroscope.)
Insertion of stomach tube (through the fluoroscope.)
Chest X-ray