Post on 13-Jan-2016
Mortality Conference– FESS and Pulmonary Hyperten
sion
R1 陳建宇 / VS 李宗勳
Brief History (1)
81/3/6: BOD 81/6(3m/o): s/p Kasai operation 86/6/24 (5y/o): RV: 66/6 mmHg/ MPA: 63/
17mmHg 87/4/27 (6y/o): Living related liver transpla
ntation( Prednisolone, FK506)
Brief History (2)
89/5(8y/o): MgSO4, PGE1 for pulmonary HTN
89/8/24: RV: 123/21 mmHg/ MPA: 120/75 mmHg, start i.v. use of PGI2 7 ng/kg/min
89/10/13: Timentin and Vancomycin for Pseudomonas and MRSA
89/10/17: FESS
EKG
89/8/24
CXR
89/10/7 89/10/17
Anesthesia Course(1)
Induction drugs:
Fentanyl 1ml
Pentothal 125mg
Atracurium 15mg
Droperidol 0.5mg Gas:
Isoflurane
ETT: 5.5mm with cuff (17cm)
A-line: L’t pedal a. I/O: 300/300ml
Anesthesia Course(2)
Brief History(3)
89/10/17 3:50pm: Transferred to PICU-- bradycardia, desat
uration; CPR; ABG revealed metabolic acidosis. Pupil was dilated.
7:05pm: Another episode of bradycardia followed by asystole happened
8:00pm: ECMO 89/10/19 12:10am: expired
Pulmonary Hypertension
Primary (Idiopathic)Pulmonary Hypertension
Secondary Pulmonary Hypertension Postoperative Pulmonary Artery
Hypertension
Primary Pulmonary Hypertension
A progressive, fatal d’x PAP↑PVR↑ Mean pressure>25mmHg Young population, F>M Median survival from time of diagnosis is
2-3 years
Secondary Pul. HTN
Causes:
L’t heart dysfunction, Hypoxic lung d’x,
L’t to R’t shunt, Liver d’x Same treatment as PPH
Postoperative Pul. Artery HTN
Especially perioperative Rapidly fatal
Treatment of Pul. HTN
Conventional Mamagement• General support care• Hyperventilation• Pharmacologic vasodilator
General Support Care
CO2:
O2 with mechanical positive-pressure ventilation(PPV)
PH Blood Pressure Narcotics and muscle relaxants can
decrease the morbidity and mortality
Hyperventilation
To produce respiratory alkalosis:• Pulmonary circulation is sensitive to hydro
gen ion than CO2 • Respiratory alkalosis promotes PGI2 relea
se High intrathoracic pressure may compromi
se CV function and exacerbate the hypoxemia
Vasodilator Therapy
Alpha-adrenergic antagonists Nitrovasodilators Beta-adrenergic agonists Prostaglandins Calcium channel blockers
Alpha-adrenergic Antagonists
Tolazoline Neonate PVR↓ Systemic hypotension
Nitrovasodilators
Sodium nitroprusside• Direct vascular smooth m. relaxant• Both arterial and venous smooth m. Nitroglycerin• Venous vasodilator• Reduction in PVR and PAP• Systemic hypotension
Beta-Adrenergic Agonists
Increase intracellular cAMP Isoproterenol Dobutamine
Prostaglandins
PGE1 PGI2
PGI2(Epoprostenol)(1)
Potent vasodilator and inhibitor of platelet aggregation
Adult: 5.5ng/kg/min( 5-20ng/kg/min) Effects: increase cardiac index, exercise
tolerance, subjective improvements Decrease PVR( 46+/-5%) and SVR( 50+/-
4%) Children greater than adults
PGI2(2)
Unstable at room temporature in solution and must be shielded from light, thus limiting its use to the acute setting
Iloprost is a stable synthetic analogue of PGI2
Delay the need of transplantation
PGI2(3)
Complications:
bradycardia, arrhythmia, hypotension,
prolonged bleeding time, severe
hypoxemia Abrupt withdrawal may results in rebound
pulmonary hypertension Expensive: £45,000/yr
Calcium Channel Blockers
Calcium: regulation of smooth muscle contraction
Nifedipine PAP and PVR↓ Side effects:
sinus arrest, systemic hypotension,
decreased myocardial contractility
Nonconventional Management
-- Fail to respond to conventional medical t’x
-- Only experimental and no routinely practice Mechanical ventilation Anticoagulants Experimental vasodilators Inhaled nitric oxide Extracorporeal support Transplantation
Mechanical Ventilation
Maintain gas exchange while decreasing adverse effort on CV function
High frequency ventilation( HFV) -poor outcome
Airway pressure release ventilation( APRV) -only one case
Anticoagulants
Warfarin Combined with a vasodilator Prostacyclin
Experimental Vasodilators
MgSO4:
activate adenylate cyclase which
suppress the release of catacholamine Adenosine and ATP:
rapid clearance and is relatively
selective pulmonary vasodilator
Inhaled Nitric Oxide
Most promise as a routine therapeutic tool Selective pulmonary vasodilator Both infants and adults Unknown potential toxicities
Extracorporeal Support
Extracorporeal membrane oxygenation (ECMO)
Mortality rate: 100% decrease to 40-60% Complications:
bleeding, neurologic injury and multiple
organ system failure
Transplantations
Heart/ lung or lung transplantation Three year survival rate: 50-60%
(prognosis similar to the results of i.v. prostacyclin)
Decision-making algorithm for postoperative pulmonary HTN
I. Ventilatory Strategy
1. Increase Alveolar and Arterial Oxygen
a. FiO2
b. Positive pressure ventilation
2. Alkalinization
a. Bicarbonate administration
3. Decrease PaCO2
a. Positive pressure ventilation
b. High tidal volume( 15-20 ml/kg)
c. Low ventilation rate( 15-20bpm)
d. Short inspiratory time( ,0.75sec)
4. Decrease Mean Airway Pressure
a. Low PEEP<4cmH2O
b. Low ventilatory rate
↓
If no improvement
↓
II. High Frequent Jet Ventilation
↓
If no improvement
↓
III.Pharmacologic Manipulation
1. Nitrovasodilators
2. Isoproterenol
3. PGE1, PGI2
4. Nitric oxide
↓
If no improvement
↓
IV. ECMO
Epinephrine(1)
Powerful alpha- and beta-adrenergic agonist Alpha-- Pulmonary vasoconstrction Beta-- Pulmonary vasodilation Low and medium doses-- PVR↓ Higher dose-- PVR↑ Increase of SVR> increase of PVR
Epinephrine(2)
In preinfusion high PVR p’t, high dose epinephrine may predominantly beta-adrenergic stimulation inducing pulmonary vasodilation
Side effects:
hypokalemia, hypercapnia( most common
metabolic side effects)
Discussing
Pre-evaluation: risk? 此刀非開不可嗎 ? Monitoring: CVP? Swan-Ganz? ETCO2 為何會上升 ? Anesthetic management:
對於麻醉用藥有否其他選擇 ? Drug’s effects: Bosmin, PGI2….. Why pupil dilated and bradycardia?