This document provides guidance on preoperative assessment for cardiothoracic surgery. It outlines key areas to evaluate including pulmonary function, lung mechanics, gas exchange, and cardiopulmonary reserve. A comprehensive assessment involves spirometry, arterial blood gases, exercise testing, imaging, and considering factors like predicted postoperative lung function. The goal is to identify risks for postoperative respiratory and cardiac complications so high-risk patients can be optimized or potentially alternative treatment considered.

1. PREOPERATIVE ASSESSMENT FOR
CARDIOTHORACIC SURGERY
Group 4
Muhammad Arsalan Khan
Said Khitab Shah
Liaqat Ali
Gauhar Rahman
KMU, IPMS, 3rd batch
Department of Anesthesiology.

2. Key Points
• Patients for pulmonary resection
• Three pulmonary areas observed
• Lung mechanical function
• Pulmonary parenchymal function
• Cardio pulmonary reserve
• Pulmonary resection surgery
• Patient extubated provided AWaC (alert warm and
comfortable)
• Geriatric patient are at high risk for cardiac complications
i.e. arrhythmias etc.
• Assessment for malignancy done by 4 M’s i.e. mass
effect, metabolic effect, metastases and medication.

3. Introduction
• Thoracic anesthesia
• Wide variety of diagnostic and therapeutic procedures.
• Involves lungs and other thoracic structures.
• Anesthetic technique have changed as the population of
patient presenting for cardiothoracic surgery have
changed.
• Major causes of morbidity and mortality of thoracic
surgeries are
• Respiratory complications 15-20% i.e. atelectasis, pneumonia etc.
• Cardiac complications 10 -15% morbidity i.e. Ischemia etc.

4. Initial PreoperativeAssessment
• Respiratory complication are the major cause of morbidity
and mortality.
• Following are the initial preoperative assessment for
thoracic surgeries:

6. Pulmonary Assessment
• Best assessment for respiratory function is done by
• Detailed history of patient quality of life.
• Simple baseline spirometery preoperatively to measure
FEV1 and FVC.
• Three legged assessment of lungs
• Respiratory mechanics
• Pulmonary parenchymal function
• Cardio respiratory interaction
• Basic functional units for extracellular respiration which
get atmospheric O2.
• Into alveoli
• Into the blood
• To the tissue ( reserved for CO2 removal).

7. Lung mechanical Function
•Spirometery:
• Test for respiratory mechanics and volume.
• FEV1, FVC, mechanical voluntary ventilation (MVV),
RV/TLC.
• Most valid single test for post thoracotomy
respiratory complication is ppoFEV1%.
• ppoFEV1%= preop. FEV1x (1- % functional lung tissue
removal /100)
• ppoFEV1% > 40% no or minor complications.
• ppoFEV1% <40% have complication but not in all.
• ppoFEV1% <40% are operated with acceptable
morbidity and mortality.

11. Pulmonary Parenchymal Function
• Arterial blood gas data
• PaO2 < 60mmHg
• PaCO2 > 45mmHg
• Pulmonary resection contraindicated.
• Cancer resection can successfully performed under the
above situation.
• Most useful test for gas exchange capacity of lungs is the
diffusing capacity of carbon mono oxide i.e. DLCO
• DLCO is non invasive.
• ppoDLCO% same as ppoFEV1% (<40%) have both
respiratory and cardiac complications.
• DLCO% < 20% unacceptable because of preoperative
mortality rate.

13. Cardiopulmonary Interactions
• Laboratory exercise testing is gold standard.
• Max. oxygen consumption (VO2) is best predictor of post
thoracotomy outcomes.
• Resting measurement is for 3 to 5 minutes.
• Max. working capacity is reached normally at 8 to 15 min.
• After that limitations are initiated i.e. severe dyspnea,
significant ECG abnormalities.
• Estimation of VO2 is based on age, sex and height.

14. • Predicted VO2 max (mL/min)= [(height – age)X20] whole
divided by weight.
• If VO2 is <15 mL/kg/min , the morbidity and mortality is
highly unacceptable.
• Few patients having VO2 max. >20 mL/kg/min have
respiratory complications.
• Poor exercise tolerance test is due to pulmonary versus
cardiac etiologies.
• Anaerobic threshold 55% of VO2 max. observed in
untrained person while it exceeds >80% in trained
athletes.
• Repeated blood lactate analysis documents the increase
in threshold of CO2production above the initial respiratory
quotient (ratio of CO2 production/O2 consumption).

16. Regional Lung Function
• Assessment of preoperative contribution of lung or lobe to
be resected by imaging of regional lung function.
• For any potential pneumonectomy who has ppo <40%
predicted for 80% of FEV1 and/or DLCO.
• Three techniques done.
• Radionuclide ventilation/perfusion V/Q lung scanning.
• Pulmonary quantitative CT-scanning
• MRI

17. Combination Of Tests

18. Final Assessment
• Assessment just prior to the admission of the patient to
the operating room.

19. Difficult Endobronchial Intubation
• Factors leading to suspicion of difficult endobronchial
intubation are:
 Previous radiotherapy
 Infections
 Pulmonary or airway surgery
• Assessment are made:
 Bronchoscopy report
 X –Ray, CT- Scan preoperatively

20. Preoperative chest X-ray of a patient with a
history of
previous tuberculosis, right upper
lobectomy, and recent hemoptysis
presenting for right thoracotomy possible
completion pneumonectomy.
The potential problems positioning a left-
sided double-lumen
tube in this patient are easily appreciated
by viewing the X-ray but
are not mentioned in the Radiologist’s
report. The Anesthesiologist
must examine the chest imaging
him/herself preoperatively to anticipate
problems in lung isolation.

21. Prediction of Desaturation During
One-Lung Ventilation
• Most patients suffer desaturation during OLV.
• Factors correlating are:
• High percentage of ventilation or perfusion to the
operative lung on preoperative
• V/Q scan
• Poor PaO2 during two-lung ventilation, particularly in the
lateral position intraoperatively
• Right-sided thoracotomy
• Normal preoperative spirometery (FEV1 or FVC) or
restrictive lung disease
• Supine position during one-lung ventilation

22. References
• Preanesthetic Assessment for Thoracic Surgery by Peter Slinger and Gail
Darling (pdf)
• Slinger P, Suissa S, Triolet W. Predicting arterial oxygenation during one-lung
anaesthesia. Can J Anaesth. 1992;39:1030–5.
• Kempainen RR, Benditt JO. Evaluation and management of patients with
pulmonary disease before thoracic and cardiovascular surgery. Semin Thorac
Cardiovasc Surg. 2001;13:105–15.
• Liu SS, Mulroy MF. Neuraxial anesthesia and analgesia in the presence of
standard heparin. Reg Anesth Pain Med. 1998;23(6 Suppl 2):157–63.
• Licker M, Widikker I, Robert J, et al. Operative mortality and respiratory
complications after lung resection for cancer: impact of chronic obstructive
pulmonary disease and time trends. Ann Thorac Surg. 2006;81:1830–8.
• British Thoracic Society. Guidelines on the selection of patients with lung
cancer for surgery. Thorax. 2001;56:89–108.
• Patterson AG. Pearson’s thoracic and esophageal surgery. 3rd ed.
Philadelphia, PA: Elsevier; 2008. p. 1168.