Anesthesia for Thoracic Surgery Part 2 Flashcards
explain a VATS (video assisted thoracoscopic surgery)
use of video camera and surgical instruments inserted through ports in the thoracic wall; usually 3-5 ports are used. staplers also used to resect the lung tissue and divide large blood vessels
indications for a VATS (6)
lung biopsy wedge resection biopsy of hilar and mediastinal masses esophageal and pleural biopsy pericardectomy pneumonectomy
advantages of thoracoscopic procedures over thoracotomy
smaller incision, no intraoperative rib spreading, less postoperative pain
less risk of postoperative hypoxemia
faster recovery and discharge from the hospital
thoracoscopic surgery can be performed under which types of anesthesia
local, regional, general
two lung ventilation or OLV
GA most common
pain management options for patient undergoing thoracoscopic procedures include
PCA for chest tube pain and NSAIDS usual after thoracoscopy
intraoperative considerations for thoracoscopic procedures
GA/OLV with DLT or bronchial blocker is common
infiltration with local anesthesia by surgeon prior to placement of potrs
lateral decubitus position with bean bag/axillary roll
routine monitors
minimum one large bore PIV (or 2)
arterial line usually placed
check ABG’s q30m iso
describe end of intraoperative part of thoracoscopy procedure events (3)
lung is suctioned and gently her inflated
change DLT to standard ETT if patient cannot be extubated. may want to valsalva up to 30mmHg
chest tube placed prior to closing
what type of ventilation do you do during a closed thoracoscopic procedure
one lung ventilation (deflate lung)
intraoperative complications during thoracoscopic procedures
CO2 insufflation used to improve surgical visualization in pleural cavity. this can create a gas embolism or hemodynamic compromise. do not allow them to insufflated >2LPM and anticipate increase in EtCO2
tension pneumothorax
hemorrhage
perforation of diaphragm or other organs
complications related to positioning and DLT
describe a mediastinoscopy
usually performed with lymph node or tissue biopsy to either establish a diagnosis (carcinoma of the lung, thymoma, or lymphoma) or to determine resectability of an intrathoracic tumor
performed through small transverse incision just above suprasternal notch. blunt dissection along pre tracheal fascia permits biopsy or paratracheal lymph nodes to the level of the carina.
shoulder roll and head extended
2 big things with patients undergoing mediastonoscopy
hemorrhage is possible related to vasculature. T&C and have 2U in OR and large bore IV’s
AW: do a good assessment! this includes looking at CT or MRI. if they lie flat and cough, maybe dont put those bitches to sleep ya feel.
mediastonoscopy anesthetic considerations related to artery compression
compression to innominate artery can cause poor flow to right carotid artery. therefore always put pulse ox and arterial line on the right
innominate artery supplies not only the right arm but also the right common carotid
poor cerebral perfusion results
mediastonoscopy anesthetic considerations related to airway obstruction
central airway obstruction due to compression of the trachea may occur during induction of anesthesia or during the manipulation of the mediastinoscope near the trachea
anesthetic technique for mediastonoscopy
GA with ETT and CV
placement of monitors on mediastinoscopy patient
monitor aline/pulse ox on right arm (if absent waveform, ask surgeon to reposition mediascinoscope because he is impeding blood flow to the head and arm
BP on left
90% of lymph node masses in the middle mediastinum result from
metastatic spread of malignancies
signs and symptoms associated with mediastinal masses
most are asymptomatic and discovered accidentally on CXR
symptomatic masses are usually malignant and are larger with extensive involvement
airway obstruction, impaired cerebral circulation, distortion of anatomy
other s/sx include cough, dyspnea, stridor, JVD, exaggerated changes in BP associated with postural changes. (may be related to SVC syndrome)
mediastinal tumors are frequently associated with these systemic syndromes (5)
myasthenia gravis (thymoma) cushings syndrome (thymoma, carcinoid) hypercalcemia (parathyroid adenoma) HTN (pheochromocytoma) myasthenic syndrome (lung CA)
SVC syndrome
progressive mediastinal tumor growth may result in compression of SVC, obstruction of venous drainage in upper thorax ensues
clinical manifestations of SVC syndrome
caval obstruction (venous distention in neck, thorax, and upper extremities)
edema of face, conjunctiva, neck, upper chest
external edema may be accompanied by edema of mouth, larynx, and associated with severe upper aw obstruction
cyanosis: mucosal edema, direct compression can severely compromise airflow in trachea
CO may be severely depressed due to impeded venous return from upper body or by direct mechanical compression on heart from tumor
venous back flow into upper extremity IV lines
evidence of increased ICP possible
relative contraindications to mediastinoscopy (5)
SVC syndrome previous mediastinoscopy (scar tissue) obstruction and distortion of aw (assess laying flat, scans, PFT's) impaired cerebral circulation myasthenic syndrome
absolute contraindications to mediastinoscopy (3)
inoperability
coagulopathy
thoracic aortic aneurysm
preoperative considerations for mediastinoscopy
-assess for evidence of aw compromise: dyspnea, tachypnea, tracheal compression or deviation
-preoperative CXR and CT scan are essential to assess size and location of tumor and to evaluate tracheal distortion or compression
-if AW compression is present, obtain PFT’s in upright and supine positions: flow volume loops detect AW obstruction
-many patients will favor upright position
assess for evidence of SVC obstruction. evidence of impaired cerebral circulation?
-worsening symptoms may be precipitated by muscle relaxants, coughing, and breath holding/position changes
anesthetic management for mediastinoscopy: monitoring and what to have
large bore PIVx2, may need to place in lower extremities if s/sx of SVC syndrome
monitor right radial pulse, doppler, arterial pressure line, pulse oximeter on right hand fingerr
BP cuff monitoring in left arm
peripheral nerve stimulator
complications during mediastinoscopy (4)
- acute AW obstruction d/t tumors and tracheal malasia that facilitates collapse (GA with reinforced ETT)
- anticipate intubation/ventilation difficulties (have different sized ETT’s, ensure ventilation before NMB, muscle relaxation intraop to prevent coughing or straining
- VAE: HOB often 30 degree elevation
- mediastinal hemorrhage (most common). most likely with increased CVP patients, be sure to not over hydrate
ways to induce a patient receiving a mediastinoscopy with a possible tumor that will obstruct the airway
can put them in semi fowlers, do awake fiberoptic, inhalation induction, or propofol induction with increments of prop at a time to maintain spontaneous ventilation
what is the first most common complication of mediastinoscopy
hemorrhage
what is the second most common complication for mediastinoscopy (and what to avoid)
pneumothorax, avoid N2O
what is the 3rd most common complication from mediastinoscopy and how to monitor for it
RLN injury, hoarseness during postoperative respiratory status/assessment. vocal cord paralysis and injury to phrenic nerve both possible
what can happen from compression of trachea or great vessels during mediastinoscopy
vagally mediated reflex bradycardia
if an airway obstruction or SVC obstruction occurs during mediastinoscopy
place patient in lateral, reverse trendelenburg, prone, or high fowlers. may cause mass to shift away from trachea or SVC and relieve the obstruction
anesthetic management for mediastinoscopy: emergence considerations
prior to extubation, ensure a strong full TOF, full return of aw reflexes, patients with SVC syndrome must be fully awake as they can easily obstruct
postoperative CXR on all patients to r/o pneumothorax
major complications of mediastinosopy listed (7)
hemorrhage pneumothorax RLN injury phrenic nerve injury/left hemiparesis esophageal injury air embolism dysrhythmias
summary point: patients undergoing pulmonary resection should have a preoperative assessment of their respiratory function in these 3 areas
lung mechanical function
pulmonary parenchymal function
cardiopulmonary reserve
interventions that have been shown to decrease the incidence of respiratory complications in high risk patients undergoing thoracic surgery include
cessation of smoking
physiotherapy
thoracic epidural analgesia
what is the best predictor of post thoracotomy outcome in elderly?
preoperative exercise capacity
should you run your patient less than one MAC of gas when doing OLV
you should if you can- use of IV anesthetics or volatiles at less than or equal to one MAC can decrease the incidence of hypoxemia
summary point: anesthetic management of a patient with an anterior or superior mediastinal mass should by guided by
the patients symptoms and a preoperative CT and echo
