92 



SPECIAL PHYSIOLOGY 



through the skin and subcutaneous tissue to the surface of the muscle. 

 The external jugular vein lies close to the incision externally. 



Sponge the oozing vessels until hemorrhage is checked, then using 

 forceps and ringers dissect away the fascia until you reach the external 

 margin of the sternothyroid muscle. Separate this muscle to the 

 inside, making an opening down to the carotid artery, where pulsation 

 may be felt near the trachea. Lifting the sheath which contains the 

 carotid artery and the vago-sympathetic nerve, taking care not to 



FIG. 52 



The manometer tambour : M, manometer ; Tb, tambour ; R, reservoir filled with one-half 

 saturated solution NasCOs ; T, T-tube ; Pt, pressure tube ; Cl, clamp ; C, cannula ; P, proximal 

 limb of manometer ; D, distal limb of manometer ; t, tracing point of tambour lever. 



wound the internal jugular vein, which lies in close relation to these 

 structures, tear open the sheath of the artery and nerve and separate 

 out the carotid artery to the extent of one or two inches. 



Choose a glass cannula not larger than the carotid; place the 

 large end of the cannula in the pressure tubing attached to the 

 manometer. Open the screw clamp and allow the tubes to fill with 

 the solution clear to the point of the cannula. Close the screw 



