Mechanical ventilation for robotic surgery

Dr. Nurdan BedirliGazi University Anesthesiology Department

Agenda • Respiratory challenges• Pneumoperitoneum• Steep Trendelenburg position

• Optimizing mechanical ventilation setting

Minimal invasivesurgery

Maximum invasive respiratory physiology

Respiratory problems related to robotic surgery

Learning curve

Need for multiple breathing circuits

Positioning• Trendelenburg• Reverse Trendelenburg

Pneumoperitoneum

• ↑CO2

• ↑IAP

Reverse Trendelenburg position

• FRC↑• Respiratory work↓• Thromboembolism

Respiratory System

Steep‐Trendelenburg position

• Endobronchial intubation• Atelectasis• FRC ↓• TLC↓• Compliance↓• Breathing work increases• Hypoxia

Respiratory system

Compression

Airway Chest Wall Pleura LungsAirwayresistance↑

Pleural pressure > alveolar pressureCOMPRESSION ATELECTASIA

Vena Cava

IAP↑Steep Trendelenburg

Blood shift tothorax

80 Patients 60 without COPD

20 with COPD

TV 6‐8 ml/IBW

PEEP 5‐7cmH2O

The day before the surgery, postoperative 40 min. 120 min, 24 h, 5 d 

VC

FEV1

MEF50/MIF50

What is the effect of intraoperative Trendelenburg position andpneumoperitoneum on postoperative lung function in healty lungs?

Prolonged use of steep Trendelenburg position combined with pneumoperitoneumduring surgery• Effects lung function in the postoperative period• In heathy lungs• Recovery may need 5 days• MV• low TV• constant PEEP (5‐7)• no RM

General anesthesia +Pneumoperitonium + Position

Conventional MV

Prevent hipoxia‐Improve SpO2

Low TV / PEEP<5

Alveolar injury

Postoperative complication

Lung protective ventilation prevents PPC

LPMV=Individualized mechanical ventilation

Individualizing mechanical ventilation‐key points• Preoperative risk assessment • Starts with induction of anesthesia• Optimal ventilatory setting• Low tidal volume• PEEP titration• Alveolar recruitment

• Intraoperative monitoring of lung mechanics• Crs• Pplat• Pdriving• Ptp

Preoperative evaluation

Anamnesis Airwayevaluation

Pulmonary risk

Cardiac risk

Glaucoma anamnesis

Central nervous system diseases

Tromboemboli anamnesis

Patient constent: orbital/facial edemaprolonged intubation

Induction of anesthesia• Patient positioning at the induction• Avoid supine position• 30 degree head up and reverse Trendelenburg position• NIPPV or CPAP

Intraoperative ventilatory settings

Tidal volume

Serpa Neto A, Schultz MJ, Gama de Abreu M. Intraoperative ventilation strategies toprevent postoperative pulmonary complications: Systematic review, meta‐analysis, and trial sequential analysis. Best Pract Res Clin Anaesthesiol. 2015 Sep;29(3):331‐40

Hemmes SN, Gama de Abreu M, Pelosi P, et al. on behalf oft he PROVE Network Investigators forthe Clinical Trial Network of the European Society of Anaesthesiology. High versus low positive end‐expiratory pressure during general anaesthesia for open abdominal surgery (PROVHILO trial): a multicentre randomised controlled trial. Lancet. 2014 Aug 9;384(9942):495‐50

Futier E, Constantin JM, Paugam‐Burtz C, et al; IMPROVE Study Group. A trial of intraoperative low‐tidal‐volume ventilation in abdominal surgery. N Engl J Med. 2013 Aug 1;369(5):428‐37. 

Tidal volume

Serpa Neto A, Schultz MJ, Gama de Abreu M. Intraoperative ventilation strategies toprevent postoperative pulmonary complications: Systematic review, meta‐analysis, and trial sequential analysis. Best Pract Res Clin Anaesthesiol. 2015 Sep;29(3):331‐40

Hemmes SN, Gama de Abreu M, Pelosi P, et al. on behalf oft he PROVE Network Investigators forthe Clinical Trial Network of the European Society of Anaesthesiology. High versus low positive end‐expiratory pressure during general anaesthesia for open abdominal surgery (PROVHILO trial): a multicentre randomised controlled trial. Lancet. 2014 Aug 9;384(9942):495‐50

Futier E, Constantin JM, Paugam‐Burtz C, et al; IMPROVE Study Group. A trial of intraoperative low‐tidal‐volume ventilation in abdominal surgery. N Engl J Med. 2013 Aug 1;369(5):428‐37. 

Don’t forget !

Low TV

IBW

• NIH/NHLBI ARDSNet• Women: 45.5 + 0.905 x ([boy‐cm] – 152.4)• Men: 50.0 + 0,905 x ([boy‐cm] – 152.4)

29.343 patient / Postop 30 day mortality / Hospital stay lenght

Low TV (IBW) + PEEP < 5 

Low tidal volume alone may be insufficient or even harm  the lungs

Low TV is effective only combined with PEEP

PEEP does not open collapsed alveolusPrevents the alveolus from collapse 

Individualize PEEP‐How?

• Complians• Respiratory pressure• Plato pressure• Driving pressure• Transpulmonary pressure

• IAP Robotic Surgery

• Adjust PEEP that provides• maximum complians• within safe driving pressureslimits

Monitoring

Always with RM

Robotic surgery‐ Problems relating interpretation of the pressure• Elevation of intra‐abdominal pressure• Position‐related lung volume changes• Obesity

Crit Care Med. 2013 Aug;41(8):1870‐7. 

PigInfluence of IAP

FRCPlateau and driving pressuresCL and CCWEnd expiratory and end inspiratory transpulmonary pressures

GroupsPEEP 1 cm H2O PEEP 10 cm H2O + RM (PCV‐ PIP= 40 and PEEP =20) 

• FRC reduce as IAP increase• Capacity of PEEP to preventreduce FRC is limited when IAP exceed PEEP

• TV and PEEP is constant• increased IAP result in increased Pplat and Pdriving• changes in transpulmonary driving pressure withrespect to IAP increase is negligible

• Conclusion• FRC reduced as IAP increases

• Capacity of PEEP 10 to prevent reduction of FRC is limited when IAP exceed the PEEP level

• In the presence of raised IAP• Ptp may be helpful for setting mechanical ventilator parameters

What fraction of increased driving pressure icrease Ptp and risk for VILI during robotic surgery? 

• 35 ASA II patients Robotic surgery pneumoperitoneum andtrendelenburg position• Surgery stages: Pneumoperitoneum/Pneumoperitoneum + Trendelenburg• Respiratory mechanics calculated• Esophageal baloon pressures• Respiratory flows

• Regional lung ventilation assessed• Electrical impedance tomography

• Pn + Trendelenburg• 82% increse in driving pressure (A)• 38 % increse in Ptp (B)• 198% increase in chest Wall component of driving pressure (C)

Comparion baseline withPneumoperitoneum+Trendelenburg• Ecw increased 223%• EL incresed 48% 

• During robotic surgery elastance CW is the primary contributor to total respiratory system elastance in contrast to laparoscopy• Mechanism• Not clear• Diaphragm and abdominal wall stretch• Reduced area of lung apposed to the rib cage because of Trendelenburg position• Rigid framework that the robot arms docked to the ports

Moderate‐High PEEP needed to resist IAP for robotic surgery

Recruitment + PEEP

Robotic surgery ventilationdependent on RM + PEEP

Contradications RM

Emphysema

Hemodynamic instability

Right heart failure

Increased ICP

During RM

• Arrhythmia• Newly emerged• Resistant

• SAP<90 mmHg• >3 minutes• Resistant fluid replasment and medication

Hemodynamic instabilty

• SpO2<92%• SpO2<92% before RM –5% decrease

Decreased in oxygen saturation

strategy for ventilation

FiO2 0.4

VCV ‐ tidal volume  6 to 8 mL/kg IBW

PEEP 5‐7 cmH2O

Respiratuary rate ‐ETCO2 40‐45 mmHg 

I:E 1:2

Monitor P plato and P driving

Initial

• Just after intubation• After Pneumoperitoneum

• Afterpneumoperitoneum+Trendelenburgposition• Before docking

RM‐automated

strategy for ventilation problems

Driving pressure>15cm 

H2O

Hipoksia SpO2<92 

Rule out bronchospasm andendobronchial intubation

FiO2 ↑ (not more than 50)

I:E= 1:1 

Perform recruitment maneuvers

Reduce insuflation pressure

strategy for ventilation problems

Hypercarbia

Hyperventilation

Subcutaneous emphysema

Hipoxia andhypercarbia

persistDiscuss conversion to open surgery

Summary

FiO2< 70% induction/extubation

Semi fowler‐intubation/extubation

NIMV‐induction/extubation

TV↓, Frequency↑

Minimal FiO2 

Recruitment +PEEP 

Reverse (sugammadeks)

Emergence from anaesthesiaand postoperative care

Avoide condition that negate theintraoperative efforts to recruit and

maintain an open lung

Emergence‐Optimize position

• Avoid supine position• 30 degree head up and reverse Trendelenburg position

Emergence‐Avoid ZEEP

• Avoid tracheal tube suctioning immediately before trachealextubation• NIPPV or CPAP• Don’t turn off the ventilator allowing carbon dioxide to accumulate tostimulate spontaneous ventilation• Other interventions likely beneficial• prevention of coughing and bucking on the tracheal tube

Emergence‐FiO2

• In the appropriate clinical conditions, the use of low FIO2 (<0.4)

Postoperative

• When high FiO2 (>0.8) is used during emergence• use of low FiO2 (<0.3) CPAP immediately after tracheal extubation may reducethe risk of resorption atelectasis

• Administration of postoperative supplemental oxygen is recommended when room air SpO2 decreases below 94% • Avoid routine application of supplemental oxygen withoutinvestigating and treating the underlying cause

CPAP/NIMW

• During the transition between mechanical ventilation andspontaneous breathing• Postoperative prophylactic CPAP/NIMW for patients who use thesebefore surgery• Think for patients with high risk • Obese• Robotic surgery

CPAP administered after a major surgery may reduce atelectasis, thefrequency PPC• Postoperative• CPAP of 7.5 cm H2O vs 6 L min flow of 50% oxygen by the Venturi mask mayreduce reintubation rate, PPC• CPAP of 10 cmH2O