Iguana Surgeries

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    Iguana

    SurgeriesEdited for print and up

    Scott J. Stahl, DVM

    Dipl. ABVP-Avian Pract

    Lucy Bartlett, DVMDipl. ABVP-Avian Pract

    Teresa Lightfoot, DVDipl. ABVP-Avian Pract

    Ovariectomy/Ovariosalpingectomy

    Orchiectomy

    Tail Amputation

    Adapted from Lightfoot T, Bartlett L: Exotic Companion Animal Surgeries Vol 1 CD-ROM, Zoological Education Network, 1999

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    2

    IGUANA

    PATIENT EVALUATION

    A complete physical exam, serum chemistry profile,

    complete blood count and fecal exam for parasites should

    be performed to assist in evaluation of the overall

    condition of the patient prior to anesthesia and surgery.

    It should be noted that elevated blood calcium levels arenormal in gestating iguanas.

    The caudal tail vein is the preferred venipuncture site for

    most lizards. Initial medical treatment should be adjusted

    as indicated by the blood work results.

    If sepsis is suspected, aerobic and anaerobic blood

    cultures are recommended, and antibiotics should be

    initiated to treat infection prior to anesthesia and surgery.

    Patients should be hydrated prior to surgery with balanced

    electrolyte solutions.

    Pre-surgery

    Subcutaneous fluidadministration

    Caudal tail vein

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    INSTRUMENTATION

    Surgical instruments appropriate for a small animal

    procedure are adequate if there are several small

    mosquito hemostats included. Curved iris scissors a

    useful.

    Hemostatic clips come in several sizes and are very

    but not necessary for vessel ligation. A 3-0 to 4-0

    synthetic absorbable suture material may also be us

    Clear plastic drapes allow better visualization of the

    iguanas respiration and heartbeat during surgery.

    Instrumentation for tail amputation includes Metzen

    scissors, forceps, mosquito hemostats, needle holde

    small Penrose drain, 2-0 nonabsorbable suture and

    bandaging material.

    Pre-surgery

    Instruments neededfor a tail amputation

    Instruments needed for

    an ovariectomy or an

    orchiectomy

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    4

    IGUANA

    ANESTHESIA

    Removal of food and water is recommended for 12-24

    hours prior to surgery.

    Supplemental heat is used to maintain the patient at

    approximately 85F (29.5C). It is important to keep this

    temperature consistent throughout the anesthetic

    induction, the surgical procedure, and the recovery

    phase.

    Anesthetic induction with propofol at 5-10 mg/kg IV is

    recommended. Alternate approaches for anesthesia

    include induction with ketamine at 20-40 mg/kg IM or

    tiletamine with zolazepam (Telazol) at 2-5 mg/kg IM.

    Note that the tiletamine and zolazepam combination has

    a narrow safety margin compared to ketamine.

    When the iguana is sedated, it may be further induced

    with isoflurane by face mask to allow intubation.

    Pre-surgery Basking lamp providesa heat source

    Anesthetic induction Face mask

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    The iguana is intubated. Note that the glottis is pos

    at the base of the tongue and is easily visualized. Th

    no epiglottis.

    Isoflurane gas anesthesia is maintained using a

    nonrebreathing system.

    An esophageal stethoscope or Doppler is useful foranesthetic monitoring during surgery.

    During a surgical plane of anesthesia, iguanas often

    become apneic, as the muscles involved with respir

    are paralyzed. Therefore, assisted ventilation is usua

    necessary during anesthetic procedures. Intermitten

    positive pressure ventilation (IPPV) may be provided

    the use of an automated electric ventilator to offer

    consistent and accurate ventilation for reptile patien

    Alternatively, IPPV can be provided manually with a

    technician operating the breathing bag for the iguan

    during the procedure.

    For the adult green iguana, providing IPPV 4-6 times

    minute is a good starting point. This may vary based

    the depth of anesthesia and the animals voluntary

    respiration.

    Pre-surgery

    Tongue

    Tracheal

    opening

    Endotracheal tube

    Tracheal

    opening

    Nonrebreathing

    system

    Tape

    Esophagealstethoscope

    Nonrebreathing

    system

    Ventilator

    ScottStahl,DVM,

    DiplABVP-AvianPractice

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    IGUANA

    CLINICAL SIGNS

    Both pre- and post-ovulatory egg stasis (also called egg

    binding) are common reproductive syndromes in captive

    female iguanas. The causes are numerous and often

    multifactorial. Lack of proper diet, less than optimalenvironmental temperatures, handling stress, improper

    light sources and inadequate nesting sites are some of

    the common causes of egg stasis in captive iguanas.

    Local or systemic disease may also lead to egg stasis.

    True gestation time in the green iguana is thought to be

    60-90 days. Gravid females will often stop eating for a

    3-4 week period prior to egg laying but remain active. A

    change in behavior and restlessness may occur as the

    iguana seeks a nesting site.

    A quiet, depressed, gravid female indicates a problem.

    Loss of weight or muscle mass may be evident over the

    pelvis, shoulders and limbs.

    The abdomen may distend dramatically, and eggs will often

    be palpable in the abdomen or visible on the body wall.

    Radiographs will reveal lobulated space-occupying masses

    in the caudal abdomen. Calcification of eggs may be

    visible in cases of post-ovulatory egg stasis.

    It is difficult to differentiate between a coelomic cavity filled

    with enlarged ovarian follicles and one with oviductal eggs.

    Ovarian follicles tend to be spherical and are located more

    Ovariectomy/Ovariosalpingectomy

    Distended

    abdomen

    Visible eggsin oviduct

    ScottStahl,DVM,

    DiplABVP-AvianPractice

    ScottStahl,DVM,

    DiplABVP-AvianPractice

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    dorsally in the abdomen, whereas oviductal eggs are

    oblong and are found in a more ventral/caudal locatio

    Occasionally bladder stones may cause mechanical

    binding, which can be diagnosed radiographically.

    MEDICAL MANAGEMENT

    In cases of suspected post-ovulatory egg binding, ox

    at a dose of 10-20 units/kg IM may be used in an

    attempt to stimulate oviposition; however, prior to u

    oxytocin for dystocia, the clinician must:

    Confirm eggs in the oviduct by historical informati

    (iguana has already laid some eggs), radiography

    ultrasonography, as oxytocin is contraindicated for

    pre-ovulatory egg stasis.

    Confirm the dystocia is non-obstructive via radiogr

    or ultrasonography, as oxytocin is contraindicated obstructive dystocia.

    A very short window of opportunity exists for succes

    oxytocin. It is most effective if given within 72-96 ho

    after initial oviposition, attempt at oviposition or nesti

    behavior. Eggs retained much longer will likely have

    become adhered to the oviduct, and the use of oxyt

    in these cases may result in torsion or tearing of the

    oviduct.

    Before using oxytocin, the iguana should be hydrate

    and 10% calcium gluconate (100 mg/kg IM every 6

    hours) should be administered if hypocalcemia is

    suspected. If seizures or tremors are present, calciu

    gluconate may be administered IV slowly PRN to eff

    Ovariectomy/OvariosalpingectomyIM injection of oxytocinto stimulate oviposition

    Subcutaneous fluid

    administration

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    8

    IGUANA

    INDICATIONS FOR SURGERY

    If egg stasis fails to respond to correction of environmen-

    tal or dietary factors or the use of oxytocin is inappropri-

    ate or is appropriate but nonresponsive, surgery should

    be pursued.

    Even if the eggs are safely passed during this season with

    the use of oxytocin, a similar episode will likely follow in

    future seasons, and surgery will eliminate these

    potentially dangerous issues.

    It is recommended that pet iguanas not intended for

    breeding should be stabilized and scheduled immediately

    for surgery, as ovariectomy and ovariosalpingectomy will

    resolve future reproductive issues for these pets.

    PATIENT PREPARATION

    The animal is placed in dorsal recumbency and secured

    (masking tape works well).

    The abdominal area is prepared for surgery in a routine

    manner from the xiphoid to the pubis. Povidone iodine or

    chlorhexidine surgical scrub may be used on reptiles.

    Ovariectomy/Ovariosalpingectomy

    Xiphoid process Pubis

    Midline

    Large ventral

    abdominal vein is

    usually within this area

    Small initial incision

    about 1 cm to the right

    or left of midline to

    avoid the ventral

    abdominal vein

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    SURGICAL STEPS

    Iguanas and other lizards have a ventral

    abdominal vein that is located caudal to the

    umbilical scar along the ventral midline and is

    suspended by a short mesentery from the

    linea alba.

    A paramedian incision is made 1-2 cm to the

    right or left of the midline, depending on the

    size of the iguana. The small initial incision is

    used to identify the ventral abdominal vein and

    reduce the likelihood of damaging it. This

    incision can be made with a scalpel, then

    extended with iris scissors. A large incision

    should then be made to allow good

    visualization.

    Care should be taken to avoid incising thebladder, which is often located just under the

    linea alba.

    If the ventral abdominal vein is damaged,

    ligation of the vein may be needed to control

    hemorrhage.

    Once the surgeon has accessed the coelomic

    cavity, the reproductive tract and position of

    the eggs or ova can be evaluated.

    Ovariectomy/OvariosalpingectomyInitial paramedianincision

    Ventral abdominal vein

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    10

    IGUANA

    PRE-OVULATORY EGG STASIS

    Pre-ovulatory egg stasis is characterized by

    large yellow ovarian follicles that remain

    attached to the ovaries like huge clusters of

    grapes. There can be 20 or more follicles on

    each ovary; each follicle may be approximately

    2 cm in diameter. In some cases thesefollicles are greenish in color, necrotic and

    friable. Other cases may demonstrate an

    associated peritonitis with large amounts of

    purulent material within the coelomic cavity.

    In cases of pre-ovulatory egg stasis, the

    ovaries are removed. It is not necessary to

    remove the oviducts, as they appear to

    atrophy and are not readily susceptible to

    infection.

    The left ovary is gently exteriorized and the

    vein and artery supplying the ovary are

    identified. When ligating the vessels to the left

    ovary, care must be taken to avoid damaging

    the renal vein or the left adrenal gland. The

    adrenal gland in the iguana will appear pink,

    long and relatively flat. It is located on either

    side of the renal vein and should not be

    removed inadvertently.

    Ovariectomy/Ovariosalpingectomy Follicles on ovary

    Left adrenal gland

    Renal vein

    Left ovary with follicles

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    Apertures are created in the avascular meso-

    varium, and the vessels are double ligated

    close to the ovary to avoid the adrenal gland.

    It is important to remove all ovarian tissue, as

    any remnant tissue may regenerate. A 3-0 to

    4-0 synthetic absorbable suture or vascular

    clips are used.

    Once the vessels are ligated, the tissue is

    transected between the clips or sutures.

    Ovariectomy/Ovariosalpingectomy

    Hemostatic clips

    Left adrenal gland

    Hemostatic clips

    Renal vein

    Aperture

    Transect here

    IGUANA

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    12

    IGUANA

    The right ovary is gently exteriorized with care

    to avoid damaging the vena cava. Anatomically

    the right ovary is attached directly to the vena

    cava. The right adrenal gland is located on the

    opposite side of the vena cava.

    As with the approach to the left ovary,

    apertures are created through the avascular

    areas of the mesovarium, and the vessels

    supplying the ovary are double ligated.

    Ovariectomy/Ovariosalpingectomy

    Right adrenal gland

    Caudal vena cava

    Right ovary

    with follicle

    Hemostatic clips

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    The tissue between the ligatures is transected

    and the ovary is removed. Any potential

    bleeding is noted and corrected.

    i

    POST-OVULATORY EGG STASIS

    In the case of post-ovulatory egg binding,

    multiple, whitish-colored eggs are apparent

    within the oviducts upon entering the coelomic

    cavity. Oviducts with eggs are removed, and

    the small inactive paired ovaries must be

    identified and removed.

    Ovariectomy/Ovariosalpingectomy

    Vena cava

    Hemostatic clip

    Bladder

    Multiple eggs

    in oviduct

    IGUANA

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    14

    The cranial and caudal aspects of an oviduct

    are exteriorized, and the vascular supply is

    identified.

    From the cranially aspect, the thin fimbria

    (infundibulum) is ligated with suture or

    hemoclips. Moving caudally, the small groups

    of vessels in the mesosalpinx are also ligated

    with suture material or hemoclips.

    Ovariectomy/Ovariosalpingectomy

    Applying

    vascular clips

    Ligation placed at

    the infundibulum

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    At the distal end, the oviduct is double ligated

    with suture or hemoclips close to the junction

    with the urodeum. The tissue between the

    ligatures is then transected and the entire

    oviduct is removed. Any potential bleeding is

    noted and corrected.

    The procedure is repeated with the opposite

    oviduct.

    Ovariectomy/Ovariosalpingectomy

    Bladder

    Ligature on the

    oviduct where itjoins the cloaca

    Ligation of

    oviduct

    Ligature being

    applied

    IGUANA

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    16

    After removing both oviducts, the small paired

    inactive (involuted) ovaries are identified

    dorsally and along the midline. The ovarian

    vascular supply is substantial, and the vessels

    are short. Caution must be used when

    attempting to elevate the ovaries. Often the

    ovaries cannot be exteriorized, and the

    surgeon must work within the coelom.

    When removing the left ovary, care must be

    taken not to damage the large renal vein or

    the left adrenal gland, which is often located

    between the renal vein and the ovary in the

    mesovarium.

    Anatomically the right ovary is situated very

    close to the vena cava. The right adrenal gland

    is usually found just medial to the vena cava.

    Ovariectomy/Ovariosalpingectomy

    Exteriorized ovaryattached to dorsum

    by mesovarium

    Right ovary

    Vena cava

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    Apertures are created through the avascular

    areas of mesovarium, and clips or ligatures are

    carefully placed around the vessels supplying

    the left ovary. It is important to remove all

    ovarian tissue, as regeneration of any remnant

    tissue can occur.

    The tissue between the ligatures and the ovaryis transected and the ovary is removed.

    The right ovary is removed in the same

    manner, taking care not to damage the vena

    cava. The right adrenal gland is usually found

    on the opposite side of the vena cava.

    Tissues for histopathology and swabs for

    bacterial cultures should be taken when

    indicated. If ovarian follicles or purulent

    material is present in the coelomic cavity,

    copious irrigation is recommended followed by

    appropriate use of antibiotics.

    Before closing, the ovarian ligatures should be

    checked for hemorrhage.

    Ovariectomy/Ovariosalpingectomy

    Removing ovary

    post-ligation

    Ovary

    Apertures or windows

    in avascular areas of

    mesovarium

    OvaryVascular clip

    Vascular clip

    Three vascular clips are visible

    along the vena cava at the pointwhere the ovary was removed

    Vena cava

    IGUANA

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    18

    The coelom/peritoneum is gently closed with a

    simple continuous pattern using 4-0 absorb-

    able suture. This closure is not the holding

    layer but helps to seal the coelom. The fragile

    coelom/peritoneum musculature is easy to

    tear so this tissue must be handled with care

    during suturing.

    The primary holding layer is the skin layer.

    Nonabsorbable suture material, such as 2-0 to

    3-0 nylon or polypropylene should be used.

    The tendency of iguana skin to invert is

    discouraged with the use of an everting suture

    pattern, such as a horizontal mattress pattern.

    This allows the proper apposition of the edges

    to promote faster healing.

    In general, it is recommended that sutures be

    removed in 6-8 weeks. Often skin sutures will

    be shed out during this time frame.

    Ovariectomy/Ovariosalpingectomy Muscular layerin place

    Interrupted horizontal

    mattress pattern

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    POSTOPERATIVE CONSIDERATIONS

    Recovery is usually uneventful as long as the iguana

    was in good condition prior to surgery and the prope

    temperature of approximately 85F (29.5C) is

    maintained throughout recovery.

    Butorphanol (Torbutrol) at 0.2-0.5 mg/kg IM and/o

    meloxicam (Metacam) at 0.2-0.3 mg/kg IM q24h f3-5 days may be used for pain management.

    A slight serohemorrhagic discharge from the incision

    occur for the first 24 hours post surgery.

    Post-surgical antibiotics, if necessary, should be sele

    based on culture and sensitivity results.

    Iguanas should not soak for 10-14 days following su

    Hydration can be maintained orally and by daily mis

    Oral or subcutaneous fluids may be warranted, depe

    on the condition of the patient.

    Additional supportive care postoperatively may inclu

    assist-feeding or tube-feeding with a slurry of soake

    rabbit chow and strained green baby food or other h

    fiber-based enterals.

    The iguana is placed in an incubator to recover from

    anesthesia; a hunched posture reflects abdominal

    discomfort.

    Return to normal activity and appetite should take

    3-5 days.

    Ovariectomy/Ovariosalpingectomy

    ScottStahl,DVM,

    DiplABVP-AvianPractice

    IGUANA

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    20

    INDICATIONS/CLINICAL SIGNS

    As pet iguanas mature, they may display offensive

    aggression towards owners or others, particularly during

    the breeding season. These iguanas often have free roam

    of the house and begin biting without provocation.

    PRE-SURGICAL CONCERNS

    Before recommending castration of adult male iguanas,

    offensive aggression must be differentiated from

    defensive aggression.

    Environmental changes should be initiated. These include

    decreasing the photoperiod and confining the iguana to a

    smaller territory, especially during breeding season. If

    these measures do not help resolve the problem, surgical

    castration may be considered.

    Owners should be forewarned that castration may not

    decrease the aggression. Behavioral changes postsurgery

    do not occur immediately and may not be appreciable.

    Castration is a more effective behavioral modifier in pre-

    pubescent iguanas than in mature male iguanas.

    PATIENT PREPARATION

    The animal is placed in dorsal recumbency and secured

    (masking tape works well).

    The abdominal area is prepared for surgery in a routine

    manner from the xiphoid to the pubis. Povidone iodine or

    chlorhexidine surgical scrub may be used on reptiles.

    Orchiectomy

    Xiphoid process Pubis

    Midline

    Large ventral

    abdominal vein is

    usually within this area

    Small initial incision

    about 1 cm to the right

    or left of midline to

    avoid the ventral

    abdominal vein

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    SURGICAL STEPS

    Iguanas and other lizards have a ventral

    abdominal vein that is located caudal to the

    umbilical scar along the ventral midline and is

    suspended by a short mesentery from the

    linea alba.

    A paramedian incision is made 1-2 cm to theright or left of the midline, depending on the

    size of the iguana. The small initial incision is

    used to identify the ventral abdominal vein and

    reduce the likelihood of damaging it. This

    incision can be made with a scalpel, then

    extended with iris scissors. A large incision

    should then be made to allow good

    visualization.

    Care should be taken to avoid incising thebladder, which is often located just under the

    linea alba.

    If the ventral abdominal vein is damaged,

    ligation of the vein may be needed to control

    hemorrhage.

    OrchiectomyInitial paramedianincision

    Ventral abdominal vein

    IGUANA

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    22

    Care should be taken to avoid damaging the

    coelomic organs beneath the incision.

    The fat pads will be first noted upon entering

    the coelomic cavity. The testicles are locateddeep in the coelom along the dorsal midline

    and under the gastrointestinal tract.

    Orchiectomy

    Ventral abdominal vein

    Coelomic contents

    Testicles

    Colon

    O h

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    The testicles are covered by a capsule and

    must be gently elevated to expose the vessels.

    The left testicle receives its blood supply from

    the testicular vein and artery, which are

    supplied by the large renal vein and artery. The

    left adrenal gland is located between the left

    testicle and these vessels and should be kept

    intact if at all possible.

    Medium hemostatic clips or absorbable suture

    material are used to double ligate the vesselsrunning through the transparent capsule.

    Orchiectomy

    Adrenal glandHemostatic clip applied

    Testicle

    Left adrenal gland

    Renal vein

    Stay suture

    IGUANA

    O hi t

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    24

    The testicle is removed and the area is

    checked for bleeding.

    The right testicle is attached to the vena cava

    by extremely short vessels. The right adrenalgland is located on the opposite side of the

    vena cava and is therefore easy to avoid.

    Orchiectomy

    Right adrenal gland

    Stay suture

    Right testicle

    Caudal vena cava

    OrchiectomyTesticle

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    Apertures are placed through the capsule

    and each vessel is double clipped or double

    ligated.

    A small hemostat is placed above the clips,

    and the capsule is transected.

    Orchiectomy

    Vascular clip

    Vascular clip

    Aperture

    Double clamped

    Testicle

    IGUANA

    Orchiectomy Vascular clips Abdominal musculature

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    26

    The testicle is removed and the ligatures are

    checked for bleeding prior to closing the

    coelom.

    The coelom/peritoneum is gently closed with a

    simple continuous pattern using 4-0

    absorbable suture. This closure is not the

    holding layer but helps to seal the coelom. Thefragile/peritoneum musculature is easy to tear

    so be gentle with suturing this tissue.

    The primary holding layer is the skin layer.

    Nonabsorbable suture material, such as 2-0 to3-0 nylon or polypropylene should be used.

    The tendency of iguana skin to invert is

    discouraged with the use of an everting suture

    pattern such as a horizontal mattress pattern.

    This allows the proper apposition of the edges

    to promote faster healing.

    In general, it is recommended that sutures be

    removed in 6-8 weeks. Often skin sutures will

    be shed out during this time frame.

    Orchiectomy

    Interrupted horizontal

    mattress pattern

    Vena cava

    Vascular clips Abdominal musculature

    OrchiectomyBasking lamp

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    POSTOPERATIVE CONSIDERATIONS

    Recovery is usually uneventful as long as the iguana

    in good condition prior to surgery and the proper tem

    ature of approximately 85F (29.5C) is maintained

    throughout recovery.

    Butorphanol (Torbutrol) at 0.2-0.5 mg/kg IM and/o

    meloxicam (Metacam

    ) at 0.2-0.3 mg/kg IM q24h f3-5 days may be used for pain management.

    A slight serohemorrhagic discharge from the incision

    occur for the first 24 hours post surgery.

    Post-surgical antibiotics, if necessary, should be sele

    based on culture and sensitivity results.

    Iguanas should not soak for 10-14 days following su

    Hydration can be maintained orally and by daily mis

    Oral or subcutaneous fluids may be warranted, depe

    on the condition of the patient.

    Additional supportive care postoperatively may inclu

    assist-feeding or tube-feeding with a slurry of soake

    rabbit chow and strained green or other high fiber-b

    enterals.

    The iguana is placed in an incubator to recover from

    anesthesia; a hunched posture reflects abdominal

    discomfort.

    Return to normal activity and appetite should take3-5 days.

    The owners should be reminded that behavioral cha

    may not be noticed until the following breeding seas

    OrchiectomyBasking lampprovides heat source

    IGUANA

    T il Am t tio

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    28

    Necrotic tail

    INDICATIONS/CLINICAL SIGNS

    Iguana tail amputation may be necessary in cases of

    trauma or necrosis.

    Tail necrosis may progress from the tip cranially. When

    this is the case, it is important to determine the extent of

    devitalized tissue prior to selecting the site for amputation.

    EVALUATION/PRE-SURGICAL CONCERNS

    A complete physical examination, serum chemistry profile

    and complete blood count should be performed to assist

    in the evaluation of the overall condition of the iguana

    prior to anesthesia and removal of the tail.

    Additionally, radiographs are important to determine the

    extent of bone involvement in the infected tail and to rule

    out associated metabolic diseases.

    If the iguana is in renal failure or has other metabolic

    diseases, these issues should be addressed prior to

    proceeding with tail amputation.

    Tail necrosis can occur as a result of septicemia leading

    to vascular thrombosis.

    Dysecdysis, or abnormal shed, may constrict the tail and

    result in ischemia that necessitates amputation.

    PATIENT PREPARATIONThe chosen area of tail separation is aseptically prepared.

    A wide margin between the amputation site and devitalized

    tissue is recommended when tail necrosis is progressive.

    Tail Amputation

    Area of necrosis

    dorsal to visible lineof demarcation

    Devitalized area Area prepared

    for amputation

    Tail Amputation

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    SURGICAL STEPS

    The tail of an iguana is designed to break

    away when needed to protect the lizard from

    capture by predators. This feature allows the

    tail to break at a natural point, and very little

    bleeding takes place. The surgeon holds the

    tail with one hand cranial and one hand

    caudal to the area chosen for the break.

    The tail is bent and twisted at the same time.

    The combined forces applied are lateral and

    dorsoventral with some rotation. On a large

    iguana, a fair amount of force is necessary to

    separate the tail.

    Audible popping will precede separation.

    Muscle tissue will extend from both ends as

    the tail separates. Bleeding is minimal tononexistent.

    The protruding tissue may be trimmed flush

    with the skin or left as is.

    p

    IGUANA

    Tail Amputation

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    30

    Two pieces of Penrose drain are cut and

    placed on either side of the remaining tail.

    Nonabsorbable 2-0 suture material is placed

    in a simple interrupted pattern through the

    skin and the Penrose drain on each side.

    The Penrose drain and sutures are used to

    decrease the area of exposed muscle tissue

    and pull the edges of the skin closer together

    without directly apposing them. The tail will

    grow back more slowly if the skin is closed

    over the amputated end.

    A gauze pad with antibiotic ointment applied

    is placed on the end of the tail to absorbdrainage.

    The tail is bandaged to prevent contamination.

    Vetrap

    Antibiotic ointment

    on gauze pad

    Tail Amputation

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    POSTOPERATIVE CONSIDERATIONS

    The bandage is changed every 2-3 days. The suture

    drain material are removed in 7-10 days.

    Postoperative antibiotics are used at the surgeons

    discretion.

    The tail remains bandaged until a smooth layer of p

    granulation tissue covers the amputated area.

    The tail will begin to regrow 3-6 weeks after surgery

    The regrown tail will be slightly smaller in diameter t

    the original tail, and the scales will be smaller and dThe regenerated section of tail will lack the ventral t

    vein and bones.

    Regrown tail

    Healthy granulation Tail regrowth

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    1. Frye F: Biomedical and Surgical Aspects of Captive

    Reptile Husbandry 2nd ed. Melbourne, FL, Krieger

    Publishing Co, 1991.2. Johnson-Delaney CA: Exotic Companion Medicine

    Handbook. Lake Worth, FL, Zoological Education

    Network, 2000.

    3. Mader DR (ed): Reptile Medicine and Surgery 2nd ed.

    Philadelphia, PA, WB Saunders Co, 2006.

    4. Stahl S: Reproductive diseases in the green iguana.Proc No Am Vet Conf, 1998, pp 810-813.

    5. Stahl S: Surgical resolution of reproductive disorders

    in female green iguanas. Exotic DVM 1(0):5-9, 1998.

    6. Stahl S: Reptile Obstetrics. Proc No Am Vet Conf,2006, pp 1680-1683.

    Zoological Education Network 2006

    Photographs copyrighted by Teresa Lightfoot, Lucy Bartlett and Zoological Education Network except photos by Scott Stahl and Stephen Hernandez-Divers where noted.

    REFERENCES AND FURTHER READING