DEPARTMENT OF ANESTHESIOLOGY SUGGESTED GUIDELINES

 

 

SUBJECT:

 

 

EFFECTIVE

DATE:                     2/14/02                 

 

SECTION:    ?

 

 

PROTOCOL FOR SURGERY IN THE SITTING POSITION

 

 

DATE 

ISSUED:                 2/14/02 

 

Revision:

 

 

 

PREPARED

BY:          Michael McCormick, MD

 

PAGE: 1 of 2

 

 

 

APPROVAL:          Witold Waberski, MD

Clinical Chief

                                Department of Anesthesiology

 

 

I.                   Introduction

Sitting position is currently being used for cervical spine procedures and posterior fossa craniectomies in neurosurgical operating rooms. Neurosurgeons who use this position include Drs. Druckemiller, Kvam, Polletti and Rossi. Other (non-neurosurgical) procedures that require the sitting or head-elevated position may include arthroscopic and open procedures on the shoulder, head and neck procedures, plastic and reconstructive breast surgery, and procedures not specified in which the head is elevated above the heart during surgery.

 

II.                Patient Selection

A.     Absolute Contraindications:  Hypovolemia, cerebral vascular insufficiency in upright position, known patent foramen ovale or ASD.

B.     Relative Contraindications:  Known cervical stenosis can lead to spinal cord stretch, compression or ischemia from inadequate perfusion. ASA III/IV patients with known severe cardiac disease (severe pulmonary disease is not a contraindication for the sitting position).

 

III.             Management Considerations for Surgery in the Sitting Position

 

A.     Monitoring. Continuous ECG and pulse oximetry. Whenever possible continuous, non-invasive arterial pressure monitoring is desirable to monitor for unwanted hypotensive / bradycardic events during shoulder arthroscopy

 

B.     Positioning. Normal body alignment should be maintained without flexion or extension beyond the usual ranges of motion for the patient. Correct positioning of the head is crucial. Extreme neck flexion  can stretch the spinal cord and it can obstruct venous drainage from the face and tongue. Extremes of head rotation can alter flow in the vertebral artery system. Positional changes should be accomplished slowly to allow for maximum hemodynamic compensation.

 

C.     Anesthetic Technique. Deliberate hypotensive anesthesia is not recommended without continuous cardiac function and blood pressure monitoring. Patients should be observed closely for vasovagal episodes whenever brachial plexus anesthesia is used alone or in combination with general anesthesia (Activation of Bezold-Jarisch Reflex)

 

IV.              Special Management Considerations for Neurosurgical Procedures

 

 

A.     Monitoring

1.      Precordial Doppler

2.      ETCO2 or ETN2 monitoring

3.      “Long arm” CVP

Arrow #16 G ACF Catheter

Advantages: Multi-orifice, protective sheath allows movement of

catheter during the case, ECG port allows exact positioning of

catheter tip, requires initial placement of only a #18 G jelco.

Disadvantages: Length of catheter and absence of markings could

allow inadvertent placement in pulmonary artery, guide wire increases risk of arrythmias with placement.

Placement “Hints”: Veins of choice (best to worst) Right basilic, Left Basilic, Right cephalic, Left cephalic.  Arm abducted 900 with head turned toward site of insertion.  The patient complaining of pain in the shoulder or neck indicates a problem with insertion.  (This is my reason for placing the catheter while the patient is awake). If catheter placement via the anticubital fossa fails our protocol is to proceed without the catheter for cervical laminectomies or discs.  We do not place IJ or subclavian lines for the specific purpose of aspirating air.

 

B.     Anesthetic: Most use Desflurane, 1-3 ug/kg fent, muscle relaxant of choice   and 100% 02.  (Avoid N20) Watch BP while patient placed in sitting position.  (A-lines not used unless indicated by CV status.

 

C.     VAE Protocol:  Doppler indicates air!

1.                                    Check ETC02 (2 mmHg drop) or ETN2 (.2% increase) as these would indicate significant air.

2.                                    Inform surgeon

3.                                    Jugular venous compression(surgeon looks for new sites of  bleeding)

4.                                    Maintain cardiac output

5.                                    Aspirate catheter

6.                                    Modify position

 

References

 

Warner, MA.  Positioning in Anesthesia and Surgery.

 

Conroy JM, Dorman BH.  Anesthesia for Orthopedic Surgery. Raven Press 1994