pulmonary hypertension and general anesthesia

1. PULMONARY HYPERTENSION
& ANESTHESIA
Dr. wesam farid Mousa
Dr. Salwa hassan khalil
Anesthesia & Surgical ICU Department
Faculty of Medicine
Tanta University

2.  Definition.
 Classification.
 Pathogenesis.
 Diagnosis and treatment of PH.
 Peri-operative management of PH crisis.
 PH in special situations.
.
objectives

3. Pulmonary circulation is a high flow, low resistance circuit
capable of accommodating the entire right ventricular output
at one-fifth the pressure of the systemic circulation.

4. DEFINITION
PH is defined as a mean pulmonary artery pressure greater than
25 mmHg at rest based upon right heart catheterization
measurements .
A mean pulmonary artery pressure of 8 to 20 mmHg at rest is
considered normal,.

5. RV enlargement
secondary to any
underlying cardiac or
pulmonary disease.
Pulmonary hypertension is
the most common cause of
cor pulmonale.
Cor pulmonale

6. An estimated 15 to 52 people in 1 million have
PAH world wide.
Armin Sablotzki1, Hans-Juergen SeyfarthJochen Gille1, Stefan Gerlach1, Michael Malcharek1 and Elke Czeslick.
Critical Care and Pain Medicine, Klinikum St. Georg gGmbH,
Germany Department of Pneumology, Universitätsklinikum Leipzig AöR, Germany
Clinic for Anesthesiology and Critical Care Medicine, Martin-Luther-University of Halle-Wittenberg, Germany2015
Epidemiology

7. CLASSIFICATION

8. A distinction between
pre-capillary and post capillary PH is
fundamental to understand the vascular and
hemodynamic changes present in patients
with PH.

9. VC RA RV PA PV
PC
LA LV Ao
Post-Capillary PH
(PCWP>15 mmHg; PVR nl)
Systemic HTN
AoV Disease
Myocardial Disease
DCM,HCM,ischemic CM
RCM,Obesity , others
Atrial Myxoma
Cor Triatriatum
PV
compression
PVOD
PAH
Respiratory
Diseases
PE
Pulmonary Hypertension: Define Lesion
MV Disease
LVEDP
Pre-capillary PH
PCWP<15 mmHg
PVR > 3 Wu

10. CLASIFICATION
Mean PAP (mmHg)
25 - 40
41 - 55
>55
Degree of disease
 Mild
 Moderate
 Severe

11. NORMAL REVERSIBLE DISEASE IRREVERSIBLE DISEASE
Pathogenesis of Pulmonary Arterial
Hypertension

12. DIAGNOSIS OF PH
Symptoms of PH
 Dyspnea 60%
 Fatigue 19%
 Near syncope/syncope 13%
 Chest pain 7%
 Palpitations 5%
 Leg edema 3%

13. PHYSICAL EXAMINATION
 Loud pulmonary component of the 2nd heart sound
P2 (increases PAP)
 Left parasternal lift (RV heave=R sided overload)
 Systolic ejection murmur of TR
 S3 gallop (advanced RV failure)
 Signs of RV failure:
 Jugular venous distention
 Hepatomegaly
 Perepheral edema
CLEAR LUNGS

14. INVESTIGATIONS:
Right heart catheterization is the gold standard to
confirm the diagnosis and establish the severity of
PH.
Transthoracic echocardiogram (TTE) remains the
method of choice for screening and assessing the PH
when clinically suspected.
Once the diagnosis is confirmed, other diagnostic
tools assist in establishing the underlying etiology and
clinical group to which the patient belongs.

15. Diagnosis Associated condition
Echocardiography Left ventricular systolic and
diastolic dysfunction
Left-sided valvular heart disease
CHD with systemic to pulmonary
shunt
X-ray chest, PFT COPD, sarcoidosis
Interstitial pulmonary fibrosis
V̇ /Q̇ scan, CTPA Chronic thromboembolic pulmonary
disease
Sleep study Obstructive sleep apnoea
Serological test
(ANA, HIV) Lupus, scleroderma, HIV
Liver ultrasound Portopulmonary hypertension
Right heart Catheterisation CHD with systemic to pulmonary
shunt
Postcapillary PH due to left heart
disease
Cardiac MRI CHD, cardiomyopathies
Over night Oxymetry PH with OSAH

16. ALGORITHM FOR INVESTIGATION OF SUSPECTED PH

17. TREATMENT OF PH
Goals of Therapy
 Alleviate symptoms, improve exercise capacity
and quality of life
 Improve cardiopulmonary hemodynamics and
prevent right heart failure
 Delay time to clinical worsening
 morbidity and mortality

19. TERAPUTIC TARGETS FOR PH

20. ANESTHETIC MANAGEMENT OF PH.
PH is a serious condition.
perioperative mortality of 7-24%.
Peri-operative morbidity 14–42% includes:
 Respiratory failure
 Heart failure, dysrhythmias
 Sepsis,
 Renal insufficiency,
 Myocardial infarction.

21. pre-operative evaluation:
Multidisciplinary team anesthetists, surgeons, pulmonologists
and cardiologists.
Patients ‘suspected’ of having PH and ungraded severity are at high
risk of peri-operative complications.
Elective surgery must be postponed till a proper pre-op evaluation &
optimization.

22. pre-operative evaluation:
Patient with established PH should be based on a risk
assessment :
 functional state
 severity of the disease
 type of surgery.

23. WHO CLASSIFICATION OF FUNCTIONAL STATUS
OF PATIENT WITH PH

24. SIGNS OF DISEASE SEVERITY
 Dyspnea at rest ( WHO- FC class 4)
 Low cardiac output with metabolic acidosis
 Hypoxemia
 Signs of right heart failure
 Syncope (poor prognosis)
 Chest pain (secondary to RV ischemia)
 Rapid progression of symptoms
 6 minute walking test <300m.

25. PREOPERATIVE MANEGMENT

26. pre-operative evaluation:
A detailed history and physical examination should be
complemented with relevant investigations :
Laboratory tests, electrocardiography, chest radiography,
arterial blood gas analysis, echocardiography,
recent right heart catheterization which is the gold standard for
diagnosis of PH.

27. PREOPERATIVE MANEGMENT
Ideally before surgery, mean PAP should be reduced to a normal of
25 mm Hg.
If substantial RV dysfunction is present, the advisability of surgery
should be reexamined.
Any chronic pulmonary hypertensive therapies that patients are
currently taking should be continued perioperatively to avoid
rebound PH
 Short acting anticoagulant like heparin should replace indirect
anticoagulant until the surgical procedure.
 Avoid anxiety, pain, and sympathetic stimulation.
 Avoid over sedation and hypoventilation.
 Antibiotic prophylaxis must be given.

28. INTRAOPERATIVE MANAGEMENT
Anesthetic and Hemodynamic goals for PH :

29. ANESTHETIC CONSIDERATIONS
Intraoperative “basic treatment” to avoid an increase of pulmonary
arterial pressure:
 “Luxury”-oxygenation with inspiratory FiO2 0.6 – 1.0
 Moderate hyperventilation (goal: PaCO2 30-35 mmHg)
 Avoidance of metabolic acidosis (pH > 7.4)
 Recruitment-manoeuver to avoid ventilation/perfusion-mismatch.
 Low-tidal-volume ventilation to avoid over-inflation of aveoli (goal: 6
ml/kg ideal body weight)
 Temperature management to maintain body temperature of 36-37
°C
 “Goal-directed” fluid- and volume-therapy with hemodynamic
monitoring

30. INTRAOPERATIVE MANAGEMENT
Optimize RV function and CO with adequate preload, SVR,
and avoid contractility, avoid myocardial depressants
Consider pulmonary vasodilators to decrease RV afterload
Maintain sinus rhythm.
It is good practice to remove air from intravenous syringes
and lines

31. MONITORING
There is no strong evidence to suggest that any specific type of
monitoring has an influence on patient morbidity and mortality.
The standard monitoring is considered sufficient for minor &
medium procedures in functional state 2.
All major interventions and those in functional state III should be
carried out under extended monitoring.
Transesophageal echocardiography (TOE).
pulmonary artery catheter.

32. MONITORING
Invasive arterial monitoring before anesthetic induction
 Early recognition of hemodynamic instability.
 Intermittent arterial blood gas sampling to check adequacy
of ventilation.
Right atrial pressure measurement (central venous
pressure)reflects the relationship of blood volume to the
capacity of the venous system and also reflects the functional
capacity of the right ventricle.

33. ANESTHETIC TECHNIQUES
All standard anesthetic techniques
can, in principle applied to patients with PH

34. ANESTHETIC TECHNIQUES
Regional anesthetic techniques:
 Not impairing spontaneous breathing
 postoperative analgesic therapy
Nearly all patients with pulmonary hypertension receive
continuous anticoagulant therapy; this fact must be taken under.
In severe PH or in diseases affecting the lung, patients cannot
be subjected to remaining in a flat position for long period of
time.
Regional anesthesia combined with careful GA to ensure
adequate oxygenation.

35. GENERAL ANESTHESIA
the main advantages are
Safe oxygenation , uncomplicated airway management, and
intraoperative selective pulmonary vasodilation can – if
necessary – easily be administered through the breathing
circuit.

36. GENERAL ANESTHESIA
All standard induction anesthetics can be used in combination with
opioids, as they have no influence on pulmonary vascular
resistance and oxygenation.
Ketamine may PVR due to catecholamine effect. However
patients with RV failure may be catecholamine depeleted.
Histamine-releasing muscle relaxants (atracurium , mivacurium)
should be avoided for patients with PH, PVR.

37. GENERAL ANESTHESIA
Volatile anesthetic agents of concentrations up to 1 MAC can
be administered without any negative effects on pulmonary
pressure and resistance.
Nitrous oxide better avoided as it may raise PVR.
So use balanced technique, mixing higher doses of opioids
and low-dose volatile anesthetic agents ,careful with stress
response during intubation.

38. During Extubation:
Maintaining haemodynamic stability and adequate ventilation
can be difficult.
Deep extubation
 May decrease SVR, contractility
 Hypoxia and hypercarbia will increase PVR
Awake extubation
 Can cause severe pulmonary vasoconstriction
 Need tube tolerance without increased sympathetic tone
Patient may need post-op ventilation with ICU admission

39.  postoperative monitoring until pulmonary pressures and
right-sided heart functions have stabilized at the preoperative
level.
 sufficient analgesic therapy in the form of continuous regional
anesthesia to avoids higher doses of opioid-based analgesics.
 The specific therapy for PH should be resumed at the
preoperative dosage as soon as possible.

 In the postoperative course, it is also advisable to treat
pressure elevations.
POSTOPERATIVE MANEGMENT

40. PERI-OPERATIVE MANAGEMENT OF PH CRISIS

41. PULMONARY HYPERTENSION WITH LAPAROSCOPY
Pneumoperitoneum with CO2 causes an increase in end tidal carbon
dioxide. Acidosis, arrhythmias ,decrease preload PH crisis.
post operative benefits of laparoscopic surgery must be balanced with
intraoperative risk involved.
IAP to be maintained at 10-12 mm of Hg.
CO2 insufflation slow rate to attenuate abdominal stretch response
Temporarily deflate the abdomen if necessary.
Combined general with epidural anaesthesia
 decreasing intraoperative anaesthetic requirement.
 post operative pain relief.

42. PULMONARY HYPERTENSION WITH PREGNANCY
Mortality rate of 30% in patients with idiopathic PAH and 56% in
patients with PH associated with other conditions.
GA associated with a four-fold increase in maternal mortality
Physiological increase in blood volume causes volume overload
in the right heart may cause:
 thromboembolic events.
 cerebrovascular accidents.
General principals for high risk parturient.
Left lat. Position .

43. Fetal monitoring as IUGR due to hypoxemia and increased
Hct level.
Anticoagulation is usually recommended. LMWH.
Warfarin and Endothelin receptor antagonists are avoided due
to potential teratogenicity.
Elective CS before 32 Ws allows for better planning, a
multidisciplinary team.
Oxytocine use low dose (10 units IV inf) slowly over 4-8 hr.
Methergine absolute CI

45. SUMMARY