1. Right atrium
2. Right AV valve
3. Right ventricle
4. Pulmonary semilunar valve
5. Pulmonary artery
11. Pulmonary veins
12. Left atrium
13. Left AV valve
14. Left ventricle
15. Aortic semilunar valve
17. Arteries of each organ
18. Arterioles of each organ
19. Capillaries of each organ
20. venules of each organ
21. Veins of each organ
22. Vena cava
1. Straight mayo (suture scissors)
2. Curved mayo
4. Metzenbaum carbide insert
•The tunica media, which is composed of inner layers of smooth muscle bounded by connective tissue. Smooth muscle is under the control of the autonomic nervous system.
•The tunica intima, which secretes substances that cause vasodilation or constriction, as well as substances that prevent platelet aggregation in the vessel. The structure of arteries and veins is shown in Figure 32-1.
•Gender: Adult females generally have higher blood pressure than males.
•Age: A gradual rise in blood pressure occurs from childhood to adulthood.
•Weight: Blood pressure is higher in individuals with a high body mass index, regardless of age.
•Exercise: Blood pressure rises with strenuous activity but returns to baseline level at rest.
•Diurnal (daily) fluctuation: Blood pressure tends to rise during the day and is lowest in the mornings.
b. Thoracic cavity- The aorta arises from the left ventricle of the heart to form an arch (the aortic arch). Three major arteries arise from the top of the arch: the brachiocephalic artery, the left common carotid artery, and the left subclavian artery.
c. Head- The brachiocephalic artery gives rise to the right common carotid artery, which branches to the external carotid artery and the arteries of the brain. The vertebral artery, which branches from the brachiocephalic artery, follows the cervical vertebrae and branches distally to the arteries of the head.
d. Upper extremities- The brachiocephalic artery branches into the right common carotid and the right subclavian arteries. These supply blood to the right side of the head, neck, right shoulder, and upper arm. The left common carotid artery supplies blood to the left side of the neck and head. The left subclavian artery provides blood to the left shoulder and right arm.
e. Abdomen- The descending aorta continues through the abdomen and branches to the celiac trunk, a network that gives rise to the gastric, splenic, and hepatic arteries.
f. Lower limbs- The iliac arteries divide into the internal and external iliac arteries in the pelvis and the external iliac artery converges into the femoral artery in the groin.
g. Major veins- The largest vein of the body is the vena cava, which is divided into inferior and superior segments. The venae cavae communicate with the heart through the right atrium. The superior vena cava receives deoxygenated blood from the head, neck, and upper extremities, and the inferior vena cava receives blood from the lower body and extremities.
h. Portal circulation- The hepatic portal circulation is unique in structure and function. The superior mesenteric and splenic veins converge to form the portal vein. This large vessel carries nutrients from the digestive system into the liver and also supplies about 60% of that organ’s oxygen requirements. The hepatic veins carry blood out of the liver to the vena cava.
b. Doppler scanning intensifies the sounds made by blood flowing through a vessel. The pitch, rhythm, and quality of the sound reflect pressure, volume, and flow rate.
c. Arteriography is radiographic imaging of the artery. This is done as an intraoperative, diagnostic, or interventional procedure to delineate the shape and interior surface of the arteries.
d. Intravascular ultrasound is used in both peripheral and coronary surgery to map the lumen of a vessel. A rotating flexible catheter carrying a transducer is introduced into the vessel.
b. Vascular scissors are extremely sharp and fine. Many are angled so that the tips can be easily inserted into the vessel. (Potts, De Martel)
c. Vascular forceps (pickups) have very fine serrations at the tips to allow a secure grip without tearing or slipping. The most common vascular forceps are DeBakey forceps.
d. There are few vascular-specific retractors except small vein retractors, which are also used in general surgery. Nonpenetrating shallow retractors are commonly used during superficial vascular surgery. A dull Weitlaner (self-retracting) or spring retractor should be available for skin and subcutaneous retraction in the hand, arm, or superficial leg. Handheld retractors include the Senn retractor, vein retractor, and shallow Richardson retractor. Skin hooks occasionally may be needed.
e. Small suction tips, such as the Frazier tip, are commonly used in most vascular procedures. The suction pressure should be lowered for use on the actual vessels. General surgical tips, such as the Poole (vented) or Yankauer suction tip, are used in abdominal vascular surgery.
f. A tunneler is used to burrow a channel through connective tissue to make space for a tubular vascular graft.
b. Vascular grafts are used to replace a blood vessel or to patch a vessel. Synthetic grafts are made of Dacron, polyester, or Gore-Tex. Sources of biological materials are banked human umbilical cord and autograft (usually from the saphenous vein). Grafts may be straight or bifurcated (Y-shaped). The length is measured in centimeters and the diameter reflects the outside diameter.
c. The most common method of removing thrombi is with a Fogarty-type embolectomy catheter. This is a narrow flexible catheter with a firm tip surrounded by an inflatable balloon.
d. The central venous catheter, known commonly as a central line, was introduced in Chapter 13 as a method of administering IV drugs, solutions, parenteral nutrients, and for blood draws in patients that require long or medium term therapy. Central line catheters are constructed of polyvinyl choride, Teflon, polyurethan, or silastic (silicone elastomer blend).
e. An endovascular stent is a tubular mesh implant that fits against the wall of an artery. The stent thus provides a physical barrier between the atherosclerotic plaque and the vessel lumen. It also holds the vessel open so that blood can flow freely without platelet aggregation. Stents are made of stainless steel, titanium, or a metal alloy called Nitinol.
f. During vascular surgery, blood vessels are mobilized and positioned for incision and entry. Retraction is performed with a vessel loop. Several types of loops are available. The most common is a thin length of Silastic material, which is carried around the vessel with a right-angle clamp. The ends of the vessel loop are clamped together with a hemostat. Umbilical tapes (18 inches [45 cm] by 1 8 -or 1 4 -inch [0.3-or 0.6-cm] flat, mesh cotton) are available prepackaged for use as vessel loops. A vessel loop may also be used to occlude a blood vessel by acting as a tourniquet.
g. Anticoagulation-During vascular surgery, heparinized saline solution is used to prevent coagulation in the area of the operative vessels. This prevents thrombi from forming at the surgical site and reduces the risk of embolus. Systemic heparin may be administered just before arterectomy (incision into the operative artery) begins. Heparinized saline is prepared by the scrubbed surgical technologist.
Coagulation- Hemostasis is maintained at anastomosis sites with collagen or fibrin products, such as microfibrillar collagen hemostat (Gelfoam, Avitene) or topical thrombin.
A solution of 60% Renografin is frequently used. A third syringe of IV saline is prepared to flush the contrast medium from the arteries when radiography has been completed.
A common type of balloon-expandable stent is the Palmaz stent.
The vena cava filter is inserted by percutaneous needle insertion. The procedure requires a guidewire and filter introducer. The guidewire is a fine flexible wire coated with a chemical (e.g., polytetrafluoroethylene [PTFE]), which prevents platelet aggregation and allows the wire to slide easily through the vessel. The filter itself, which resembles an umbrella without fabric, is made of titanium, stainless steel, or Nitinol.
The patient is placed in the supine position on the fluoroscopy or radiology table. The groin is prepped with povidoneiodine solution and the area is draped in the usual manner. Local anesthesia with or without sedation is administered.
A local anesthetic usually is used.
The scrub should have heparinized saline, vessel irrigation tips, vascular sutures, ties, and hemostatic agents available. A variety of vascular clamps matched to the size of the vessel (or the surgeon’s preference) also should be available on the instrument table. Small-bore suction and larger atraumatic suction tips are needed. Vascular forceps are used throughout
Carotid endarterectomy may be performed using either a general or regional anesthesia. When a regional anesthetic is used, the patient will respond to simple neurological tests, such as hand strength tests or speaking.
The suture line is observed for leaks and blood flow confirmed with Doppler. Any leaks are repaired with additional sutures and controlled with topical hemostatic agents. Protamine sulfate is administered to reverse the effects of systemic heparin.
Each artery is opened, and the proximal ends are irrigated with heparinized saline. The bifurcated graft is trimmed and distal limbs anastomosed with 3-0 or 4-0 polypropylene suture.
Heparin is administered to the patient and the femoral arteries are clamped with right angle vascular clamps. The inferior mesenteric artery is clamped to prevent an embolus from entering it when the aortic clamp is applied.
The patient is given heparin intravenously and the axillary artery is clamped. The artery is incised with a #11 scalpel blade and the anastomosis is performed with 5-0 or 6-0 polypropylene suture.
Suture lines are checked for leaks and the heparin is reversed with protamine. An angiogram may be obtained to ensure patency of the graft. Both wounds are irrigated and closed in layers.
Hemostatic agents are applied to the suture lines. Protamine sulfate may be administered to reverse the effects of systemic heparin.
During both anastomoses, the scrub should have heparinized saline solution available for irrigation of the arterial sites. Hemostatic agents are used to check bleeding at the anastomosis and additional sutures are placed if needed.
A general anesthetic usually is administered because the procedure is performed in conjunction with peripheral or cardiac bypass surgery.
Frequent irrigation with saline solution is necessary. An Asepto syringe can be used for irrigation. Some surgeons inject papaverine or lidocaine into the subcutaneous tissue to prevent vein spasm.
A general or regional anesthetic is administered.
You are relieving the surgical technologist on a bilateral femoropopliteal bypass.
a. What is the first thing you should do when you scrub in?
Patients with end-stage renal disease require frequent hemodialysis. This treatment requires long-term access to the patient’s vascular system. What surgical interventions might be needed to create a means of long-term access?