perform biopsies and collect specimens. references –c288 clinical procedures for physician...

Perform Biopsies and Collect Specimens


• References– C288 Clinical Procedures for Physician Assistants

– C348 Minor Surgery A Text and Atlas


Outline– Describe the indications, contraindications and

rationale for biopsies

– Identify and describe the common complications encountered in biopsy performance

– Describe and demonstrate common biopsy procedures

– Describe fundamentals of specimen collection with joint and bursa aspiration and lumbar punctures


General for all procedures– patients must be fully briefed about procedure,

potential risks etc and must sign an informed consent – often application of a topical anesthetic such as EMLA

can reduce the discomfort– all procedures must be performed under sterile

conditions– all specimens must be sent for pathology– areas to be biopsied or excised should be marked with a

skin marker especially those areas which may blanche when the local anesthetic is injected

Skin Biopsies

Skin Biopsies– performed to determine the cause of a lesion and often

to remove the lesion

– general categories include:

• shave

– snip

– curettage

• punch

• excision

Shave and/or Curettage Biopsy


Shave– easiest of all to perform, particularly if the lesion is

raised above the skin

– can be done with a scalpel, razor blade or special disposable blade

– removes the epidermis and a portion of the upper dermis

– is performed along the horizontal plane

– variations include snip excisions and curettage


Indication– shave biopsy

• Seborrheic keratoses

• Verrucous lessions

• Molluscum contagiosum

• Superficial basal cell carcinomas

– occasionally shave biopsy may be performed on benign nevi particularly on the face when good cosmetic results is essential.


Indication– Curettage

• may be performed on superficial lesions such as:

– Molluscum contagiosum

– Verruca vulgaris

– Seborrheic keratoses with or without cryotherapy


Contraindications– contraindications for a shave biopsy include the

following:

• most pigmented lesions, except benign nevi

• for the diagnosis of infiltrative dermatoses

• in a suspected sclerosing basal cell carcinoma

• any lesion with a dermal component


Potential Complications– bleeding

– infection

– regrowth of tissue

• lesions such as warts and incompletely removed nevi or seborrheic keratoses can regrow

• an estimated 1 in 20 nevi will regrow

– scarring

• it is more of a risk if shave is deep into the dermis

Shave Biopsy

Procedure– inject the lesion with anesthetic so a wheel is raised– hold the No. 15 blade flat and parallel with the skin

surface– use a gentle sawing motion to shave through the

lesion– the lesion may be elevated with the use of forceps or

by spearing the lesion with a needle– attempt to shave the base of the lesion completely by

shaving into the uppermost portion of the dermis

NOTE: Care must be taken not to crush the lesion with forceps which will distort the histologic specimen referred to as crush artifact

Shave Biopsy

Curettage Biopsy

Procedure– for superficial basal cell carcinomas or any other

lesion in which the use of cautery is anticipated, the lesion should be injected with anesthetic

– hold the curette like a pencil with the sharp side down

– stabilize the skin and use a quick scraping motion

– control any bleeding

Curette

Punch Biopsy

Punch Biopsy

Punch biopsy– is when a core of tissue is removed using a specially

designed biopsy instrument

– biopsy punches are made in a variety of sizes ranging from 2mm to 15mm

– rapid and simple

– smaller wound than excisional

– may not require suturing

Punch Biopsy

Indication– when a lesion or dermatosis covers a large surface area

and diagnosis needs to be confirmed prior to treatment being started

– important to take the most representative area of the lesion for the highest diagnostic yield*

– in the case of pruritic dermatoses it is best to biopsy a lesion that has not been excoriated

– for vesicular lesions an intact vesicle or bulla may provide the best diagnostic yield

Punch Biopsy

Indication cont’d– in suspected melanoma that is too large to excise at that

time, the biopsy should be obtained from the darkest or thickest area of the lesion

Contraindications– any lesion with highly suspected malignant potential

such as a melanoma that could be easily excised at the initial visit

Punch Biopsy

Potential Complications– are similar to those of shave biopsies– discomfort with the injection of anesthetic– the risk of bleeding– infection rate is higher because procedure is slightly

more invasive– scarring will occur but the extent is dependent on the

patient’s ability to heal versus the size of the end defect– Hand-held cautery is the method of choice to stop brisk

bleeding

Punch Biopsy

Punch Biopsy

Procedure– prepare and drape the area

– inject the lesion with the anesthetic

– after selecting the appropriate size punch, hold the skin taut and perpendicular to the lines of tension, wrinkles or skin folds

Punch Biopsy

–hold the punch perpendicular to the skin and place it so that the lesion is centered within the punch area

–apply downward pressure while rotating the punch

Punch Biopsy

–the punch should extend to the subcutaneous fat

–once complete, remove the punch and the specimen will remain attached to the subcutaneous fat by a pedicle

–gently lift the specimen with a pair of forceps

Punch Biopsy

–cut at the base with a pair of scissors and send for pathology

–suture the wound placing half as many sutures as the size of the punch. (I.e. a 6mm punch would require three evenly spaced sutures)

Punch

Biopsy

Excisional Biopsy

Excisional Biopsy

Indications– suspected melanomas, larger basal cell and squamous

cell carcinomas– epidermal inclusion cyst– lipomas and dermal lesions larger than 1cm

Potential Complications– anesthestic injection discomfort – risk of bleeding (cautery is best method of control) – infection– possible scarring

Excision Biopsy

Procedure– adequate knowledge of the lines of skin tension is

required to determine orientation of excision biopsies

– use a sterile surgical marker to mark the intended incision line taking into account the lines of tension, wrinkles or skin folds

Excision Biopsy

–use the tip of the 15 blade to incise the corner of the ellipse

–continue the incision through the dermis to the subcutaneous fat

Excision Biopsy

Procedure cont’d– use the forceps to lift the specimen and cut at the base

or subcutaneous fat

– once the specimen is completely removed place it in the specimen container

– if deep wound, begin closure with the subcutaneous vertical mattress sutures then place simple interrupted sutures to close the skin

Needle Biopsy

Needle Biopsy

Needle biopsy– subcutaneous lumps may be diagnosed by fine needle

aspiration rather than total excision

– this may give rapid diagnosis and help formulate a plan of action in e.g. breast lumps/cysts or lymph nodes

– as the volume of tissue obtained is very small, it must be placed in the fixative immediately

– ensure that sample is taken from a representative area

Needle Biopsy

Contraindications– when the mass to be biopsied lies close to important

structures which might be injured during the procedure

Complications– bleeding

– infection

Needle Biopsy

Procedure– usually no local anesthetic is needed

– a 21g needle is attached to a 5ml syringe

– needle is inserted into the center of the lump, moved backwards and forwards a few times and traction applied to the syringe plunger

– a vacuum is created which pulls cells into the syringe

– needle is withdrawn, contents are put on a slide and immediately covered with a fixative

Joint Aspiration

Joint Aspiration

Joint Aspiration– joint aspiration offers both diagnostic and therapeutic

benefits and permits acquisition of synovial fluid for analysis

– despite the benefits, joint aspiration is an invasive procedure with the potential for grave injury if not carried out under strict sterile conditions

– each joint has specific anatomic landmarks by which the joint space is outline and the needle can be placed for aspiration.

Joint Aspiration

Indication– painful effusion of a joint or suspicion of a systemic

rheumatic disorder of uncertain cause.

– trauma can result in painful joint effusion which can be remedied easily by joint aspiration

– in the case of articular inflammation of unknown cause, the synovial fluid analysis may be the most accurate diagnostic tool

Joint Aspiration

Contraindications– circumstances exist by which entering the joint

facilitates the seeding of bacteria into the joint

– introducing needle into joint space through burns or infected skin

– when risks for introduction of bacteria outweigh the benefits of aspiration

– after total joint arthroplasty except under the supervision of an orthopedic specialist

Joint Aspiration

Contraindications cont’d– in drainage of a hemarthrosis in a hemophiliac patient,

the hemarthrosis will re-accumulate if bleeding has not been controlled before the procedure

– patients who have been on long term anticoagulation therapy

Joint Aspiration

Potential Complications– most common complications include:

• bleeding, infection, pain, intra-articular injury and re-accumulation of fluid

– inadvertent injury to vascular or neural structures near joint spaces

– topical and systemic allergic reactions

Knee Joint Aspiration

Joint Aspiration

Patient Preparation– have the patient in supine position with knee extended

as much as effusion permits as this allows patella to ride more closely to the femur narrowing the retro-patellar space.

– tension on the anterior cruciate ligament is greatest when the knee is in full extension or deep flexion

– the patient may prefer to have a 30 to 70o flexion to maintain laxity of anterior cruciate and allow for comfort

Joint Aspiration

Procedure– the area must be cleansed and draped

– identify the joint space lateral to the patella by ballottement of the fluid beneath the patella

– draw up 1% lidocaine in a 5 or 10ml syringe

– identify the landmarks to determine the location for needle placement

Joint Aspiration

Anesthesia– draw a visual line along either lateral margin of the

patella to intersect with the line of the superior patellar margin

– enter the skin at that point or slightly more laterally and superiorly, administer a small amount of anesthetic subcutaneously.

– angle 45o off the sagittal plane and 30o off the frontal plane directing the needle caudally and advance as far as required

– as needle is withdrawn administer the anesthetic along the tract from the joint capsule out to the skin

Joint Aspiration

Joint Aspiration

Aspiration Procedure– assemble an 18 gauge needle on a 20 or 30ml syringe– hold the syringe like a pencil and align to advance

medially and caudally into the joint space behind the patella

– introduce the 18 gauge needle into the anesthetized track angled 45o laterally and directed 30o caudally

– place gentle pressure on the syringe plunger while advancing and aspirate the synovial fluid on entering the joint space as the needle is directed medially and downward behind the patella

Joint Aspiration

Joint Aspiration

Aspiration Procedure cont’d– aspirate fluid until knee joint is no longer distended or

fluid can no longer be aspirated

– withdraw the needle from the joint space and apply direct pressure with sterile dressing over the puncture site for several minutes

Bursal Aspiration

Bursal Aspiration

Indication– painful bursal swelling which persists despite

conservative treatment or when questions arise about cause

Contraindication– aspiration of a bursa is likewise contraindicated when

the risk for introducing bacteria outweigh the benefits of aspiration

Bursal Aspiration

Potential Complications– infection, pain, chronic recurrence, chronic drainage via

a sinus tract and acute recurrent swelling

– keep in mind that some bursae communicate directly with the joint space

– Baker’s cysts or popliteal bursae are actually herniations of the joint capsule

Bursal Aspiration

Potential Complications– communication between the olecranon bursa and elbow

joint may develop in rheumatoid arthritis

– when aspirating the olecranon bursa, a lateral aspiration approach is recommended to prevent subsequent development of a chronic sinus tract that can result from introducing a needle directly into the tip of the elbow bursa

Olecranon Bursal Aspiration


Positioning– if sitting the arm must be supported on a Mayo stand

flexed at the elbow to 90o

– if lying have patient rest arm on the table with elbow flexed and shoulder comfortably abducted to allow access to the lateral olecranon bursa


Anesthesia– draw up 1ml of 1% lidocaine in a syringe. Identify the

landmarks to determine the location for needle placement

– administer the anesthetic under the skin of the elbow centering the needle over the lateral surface of the distended bursa


Procedure– with the elbow flexed to 90o and resting comfortably

switch to an 18 gauge needle and syringe.

– enter into the distended olecranon bursa at 90o to the plane of the arm

– aspirate the fluid slowly until the bursal sac is flat


– apply direct pressure over the puncture site. Dress with an adhesive bandage and wrap the elbow with an elastic compression bandage to retard the re-accumulation of fluid

– observe the synovial fluid for evidence of a cloudy appearance and obtain a Gram stain, cell counts, and cultures if there is suspicion of infection.

Lumbar Puncture

Lumbar Puncture

Purpose– to obtain CSF for cell count, glucose, protein, culture

and other specialized analysis

Indications– frequently used in the evaluation of infection in

meninges, subarachnoid hemorrhage and demyelinating diseases

– may serve as a route for medication– in infants and children, may be used to relieve

increased intraventicular pressure from hydrocephalus

Lumbar Puncture

Contraindications– increased intracranial pressure

– in the presence of suspected or known coagulation disease or disorders

– presence of surface infection, severe illness or medically unstable

– in the presence of abnormalities that may be associated with spinal cord structural deformities

Lumbar Puncture

Potential Complications– most common is postdural puncture headache 30-50%

of patients

– herniation into the foramen magnum

– nerve damage

– bleeding

– infection from poor sterile technique

Lumbar Puncture

Lumbar Puncture

Procedure– ensure patient is fully briefed– check to make sure all necessary equipment is available

on tray– set up four collection tubes and pre-assemble the

manometer and attach three way stopcock– place in the lateral recumbent position with knees

flexed toward the chest and chin touching the knees– cleanse the area (sterile technique is extremely

important)

Lumbar Puncture

Procedure cont’d– identify the level of L4, which is usually at the level of

the iliac crests

– anesthetize the area with 1% lidocaine

– once surface anesthesia, the spinal needle is slowly inserted with the stylet into the L3-L4 intervertebral space

Lumbar Puncture

Lumbar Puncture

Procedure cont’d– once into the space remove the stylet and CSF should

flow

– attach the manometer as soon as fluid appears in the hub of the needle and measure the opening pressure. Have the patient gently relax the legs and breathe slowly

– collect approx. 1ml in each of the four specimen tubes

– when sufficient fluid has been obtained, replace the stylet and slowly withdraw the needle

Lumbar Puncture

Procedure cont’d– apply pressure with sterile gauze until no fluid or blood

can be detected

– observe and instruct patient re follow up care

Review Procedures

Sterile technique is paramount to any aspiration or puncture procedure

Sterile collection of fluid and prompt evaluationKnow your anatomy and landmarksPatient positioning is a big factor in proper

placementKnow the possible complications of the

proceduresKnow the indications and contraindications

perform biopsies and collect specimens. references –c288 clinical procedures for physician...

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