Parotidectomy

Anatomy and Physiology

The parotid gland is the largest of the salivary glands. It arises as an epithelial invagination in the lining of the oral cavity at about 5 weeks' gestation. The parotid gland is located anteroinferior to the external acoustic meatus wedged between the ramus of the mandible anteriorly and the mastoid process posteriorly. Its apex is found posterior to the angle of the mandible, and its base is found slightly inferior to the zygomatic arch.

The gland is divided into a larger superficial lobe and smaller deep lobe by the facial nerve, which enters the posterior parotid, branches and then exits the gland anteriorly. Adjacent to but slightly deeper to the facial nerve is the retromandibular vein, followed by the external carotid artery, both of which have a number of branches within the gland. The retromandibular vein, which drains into the external jugular vein, roughly parallels the course of the facial nerve. Therefore, this vein can be used as guide to determine the location of the nerve on imaging studies.

The parotid gland itself is enclosed by a tough fascial capsule, the parotid sheath, which is derived from the deep cervical fascia. Innervation of the parotid gland includes both parasympathetic fibers from the glossopharyngeal nerve and sympathetic innervation via the external carotid nerve plexus.

Histologically, the gland is composed primarily of acinar cells, and upon stimulation, they produce a watery, serous solution, which is excreted by the parotid (Stensen) duct. This duct exits the anteromedial portion of the gland, crosses the masseter superficially, pierces the buccinator, and enters the oral cavity opposite the second maxillary molar. In addition to parotid tissue, parotid glands typically have lymph nodes that may or may not be visible on imaging.

Pathophysiology

Pleomorphic adenomas, commonly called a benign mixed tumor, are histologically composed of 2 subtypes of cells: epithelial and mesenchymal. The tumors are typically well demarcated from the surrounding tissue by a fibrous capsule, which varies both in thickness and completeness.

These lesions have been reported to contain small protrusions (pseudopodia) that extend beyond the central mass, caused by variability in the growth rates of the various cell types. This factor contributes to recurrence rates as high as 50%, depending on the type of surgical intervention.

Hemorrhage, calcification, and necrosis are occasionally present. Most pleomorphic adenomas are confined to the superficial lobe of the parotid gland, but they can occasionally arise in the deep lobe in other salivary glands. Malignant degeneration, most commonly carcinoma ex pleomorphic adenoma, has been reported to occur in as many as 25% of untreated cases. In rare cases, pleomorphic adenomas degenerate into a true malignant mixed tumor and a metastasizing benign mixed tumor.

Discussion of Surgical Procedure

Preoperative Phase

Although the physician is responsible for explaining the surgical procedure to the patient, the patient may ask the nurse questions about the surgery. There may be specific learning needs about the surgery that the patient and support persons should know. A nursing care plan and a teaching plan should be carried out. During this phase, emphasis is placed on:

a. Assessing and correcting physiological and psychological problems that may increase surgical risk.

b. Giving the patient and significant others complete learning and teaching guidelines regarding the surgery.

c. Instructing and demonstrating exercises that will benefit the patient postoperatively.

d. Planning for discharge and any projected changes in lifestyle due to the surgery.

Intraoperative Phase

Scrub Nurse/Assistant. The scrub nurse or scrub assistant is a nurse or surgical technician who prepares the surgical set-up, maintains surgical asepsis while draping and handling instruments, and assists the surgeon by passing instruments, sutures, and supplies. The scrub nurse must have extensive knowledge of all instruments and how they are used. In the Army, the Operating Room Technician (MOS 91D) often fills this role. The scrub nurse or assistant wears sterile gown, cap, mask, and gloves.

Circulating Nurse. The circulating nurse is a professional registered nurse who is liaison between scrubbed personnel and those outside of the operating room. The circulating nurse is free to respond to request from the surgeon, anesthesiologist or anesthetist, obtain supplies, deliver supplies to the sterile field, and carry out the nursing care plan. The circulating nurse does not scrub or wear sterile gloves or a sterile gown. Other responsibilities include:

(1) Initial assessment of the patient on admission to the operating room, helping monitoring the patient.

(2) Assisting the surgeon and scrub nurse to don sterile gowns and gloves.

(3) Anticipating the need for equipment, instruments, medications, and blood components, opening packages so that the scrub nurse can remove the sterile supplies, preparing labels, and arranging for transfer of specimens to the laboratory for analysis.

(4) Saving all used and discarded gauze sponges, and at the end of the operation, counting the number of sponges, instruments, and needles used during the operation to prevent the accidental loss of an item in the wound.

Post Operative Phase

Once surgery has been completed, patient is brought to the recovery room, which also may be called the post-anesthesia care unit. In the recovery room, clinical staff will closely monitor patient as he/she recover from anesthesia. The length of time spent in recovery depends on the type of surgery performed and the individual patient. While a patient is in recovery, the clinical staff may do the following:

· monitor vital signs such as blood pressure, pulse, and breathing

· monitor for any signs of complications

· take the patient's temperature

· check for swallowing or gagging

· monitor the patient's level of consciousness

· check any lines, tubes, or drains

· check the wound

· check intravenous infusions

· monitor the patient's bladder distention

· maintain the patient's comfort with pain medication and body positioning

Nursing Responsibilities

Circulating Nurse

The Surgical Technology student can assist the Registered Nurse with the following:

A. Clean operating room and discard suction prior to case.

B. Gather all supplies, instruments and equipment necessary for case.

C. Arrange O.R. furniture properly.

D. Open and flip sterile supplies for the surgical procedure.

E. Assist with IV therapy.

F. Assist the anesthesiologist.

G. Assist with the skin preparation.

H. Tie gowns of the scrub nurse and surgeon.

I. Provide scrub personnel with sitting stools and foot stools as necessary.

J. Turn and help adjust lights as necessary.

K. Supply the scrub nurse with necessary supplies.

L. Receive and label specimen properly.

M. Log and deliver specimen to pathology properly.

N. Help apply wound dressing.

O. Pull case for following procedure.

Scrub Nurse

1. Perform surgical hand scrub.

2. Gown and glove using closed glove technique.

3. Re-gown and glove when breaks in technique occur.

4. Assist the 1st scrub in setting up case (back table, mayo stand and O.R. basins). The tasks include:

A. Arrange instruments and supplies (back table, mayo stand and O.R.).

B. Count needles, instruments and sponges.

C. Check instruments for proper functions.

D. Prepare irrigating solution.

E. Draw medications properly.

F. Gown and glove surgeon and assistant.

G. Assist with draping.

H. Prepare electric cautery, suction and light handles for proper use.

I. Prepare necessary sutures.

J. Pass instruments to surgeon and assistant.

K. Retract, sponge, and suction during case as necessary.

L. Proper identification and handling of specimen.

M. Prepare instruments for decontamination at completion of case.

N. Dispose of sharps properly.

O. Discard soiled drapes and trash properly.

P. Transport soiled drapes and trash properly.

Q. Anticipate the surgeon and assistant needs.

R. Anticipate the operative procedure needs.

S. Help apply wound dressing.

Bibliography

http://emedicine.medscape.com/article/384327-overview

http://www.ghorayeb.com/ParotidectomyFAQ.html

http://www.harlingen.tstc.edu/surgtech/scrub.aspx

http://www.brooksidepress.org/Products/Nursing_Fundamentals_II/lesson_8_Section_2.htm

http://www.stjohns.com/healthinfo/adult/surgery/postop.aspx

http://www.entnursing.com/parotidectomy.htm