A lemon can sometimes help

Aintree

pharmacology of anesthesia

Pharmacology of Anesthesia Exam 1 » online testing software

general anesthesia quiz

Alkadhi s General Anesthesia » quiz software

anesthesia quiz

GETA for C-Section » Make A Quiz

just for fun

A cardiac anesthesiologist is flying across the country for a conference, when a flight attendant comes running down the aisle, shouting, "Is anyone on board a cardiac anesthesiologist?!?!"

The anesthesiologist raises his hand and announces his presence, and asks what the problem is, and whether anyone is sick.

"Oh, no, no one's sick, but there's a cardiac surgeon up in first class who needs his table adjusted."

THE PATIENT WITH PULMONARY HYPERTENSION

ANAESTHESIA FOR THE PATIENT WITH
PULMONARY HYPERTENSION
ANAESTHESIA TUTORIAL OF THE WEEK 228

JUNE 2011
Dr Sarah Thomas, Senior Anaesthetic Registrar
Royal Hobart Hospital
Correspondence to sarah.thomas@dhhs.tas.gov.au
QUESTIONS
Before continuing, consider the following scenario and question.  The answers can be found at the end
of the article, together with an explanation.
You are to anaesthetise a 65-year-old woman for laparoscopic sigmoid colectomy.  She has recently
been diagnosed with colorectal carcinoma.  The patient has been a heavy smoker in the past and has
severe chronic obstructive pulmonary disease (COPD), with secondary pulmonary hypertension.  She
also has essential hypertension.  Medications include a beta-blocker, ACE inhibitor, inhaled
steroid/beta-agonist and aspirin.
What are your concerns in anaesthetising this patient?
INTRODUCTION
The disease spectrum of Pulmonary Hypertension (PH) has received greater interest in the past decade,
as specific therapies have been developed and survival has improved.  More patients with PH are now
presenting for surgery, and this poses a challenge to the anaesthetist.  Knowledge of the underlying
physiology is paramount in preventing the feared complication of right heart failure.
DEFINITION AND CLASSIFICATION
Pulmonary Hypertension is defined as a mean pulmonary artery pressure (PAP) >25mmHg at rest with
a pulmonary capillary wedge pressure <12mmHg.   Pulmonary hypertension is considered moderately
severe when mean  PAP >35mmHg.  Right ventricular failure is unusual unless mean PAP is
>50mmHg.
The World Health Organisation classifies pulmonary hypertension by aetiology into five groups. The
disease, including its classification, was comprehensively reviewed at the 4
th World Symposium on
Pulmonary Hypertension in 2008.
Table 1: Clinical classification of pulmonary hypertension
1 Pulmonary Hypertension (PAH)
2 Pulmonary hypertension owing to left heart disease
3 Pulmonary Hypertension owing to lung disease
4 Chronic thromboembolic pulmonary hypertension (CTEPH)
5 Pulmonary hypertension with unclear multifactorial mechanisms
Group 1 includes the disease idiopathic pulmonary hypertension (formerly known as primary
pulmonary hypertension), as well as PH associated with connective tissue disorders. This group of
diseases share similar pathological findings and clinical appearance.  The incidence of idiopathic PH is
higher than previously thought, although remains relatively rare at 15 per million.
Of greater interest to the anaesthetist are the more common forms of PH: those due to left heart disease
(group 2) and those due to lung disease (group 3).  Cardiac anaesthetists have long been familiar with
PH due to left heart disease,  which often occurs  in patients undergoing cardiac surgery.  Examples
would include patients with mitral valve disease undergoing valve replacement, or patients with severe
LV failure undergoing coronary bypass surgery.
Non-cardiac anaesthetists are more likely to encounter PH in patients with lung disease.  Underlying
diseases include COAD, interstitial lung disease, and sleep disordered breathing.  The majority of
patients in this group have modest PH.
PITFALLS IN DIAGNOSIS
Pulmonary hypertension may be suspected after  patient  assessment  based on history, examination,
ECG and chest x-ray.  The symptoms of PH are non-specific, and diagnosis can be delayed.
If PH is suspected, transoesophageal echocardiography (TTE) is usually the first investigation
undertaken.  TTE utilizes Doppler across a tricuspid regurgitant jet, to estimate pulmonary artery
pressure.  This technique has been shown to under or over estimate PAP in up to half of patients at risk
of PH, and therefore as a diagnostic test has limitations in accuracy.
Right heart catheterization is required to confirm the diagnosis.  A vasodilator challenge forms part of
this assessment.