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186
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and ideal; but it is costly. It has very less side effects. TPA
dose is 50 mg over 2 hours IV.
¾
TPA pulse-spray method: Here lysis occurs in 6 hours.
Severe ischaemia causes oedema in the muscular compartment
with raise in compartment pressure more than the essential
capillary perfusion pressure causing acute compartment
syndrome. It is common in the anterior compartment
CONTRAINDICATIONS FOR THROMBOLYSIS
B
x Recent stroke, Recent eye surgery, Pregnancy
x Recent major surgery or major bleed like of varices
x History suggestive of or confirmed active duodenal/gastric ulcers
x Uncontrolled hypertension or coagulation disorders
of the leg. It is basically in the skeletal muscles deep
to deep fascia. Compartment pressure when measured
using transducer needles will be more than 40 mmHg or
>30 mmHg for 3 hours or above the mean arterial pressure.
Muscle weakness, sensory changes, leg pain which is
aggravated by dorsiflexion of toes.
Advantages and disadvantages of thrombolysis
T
Advantages Disadvantages
SRB’s Manual of Surgery
• Gentle angiographic clot
removal
• Survival and limb salvage is
equal
• It is mainly useful for acute
thrombus
• For embolus it is used often as an
adjunct along with embolectomy
• It avoids surgery
• Useful only for class I and
IIa acute ischaemia
• Bleeding at the site and
elsewhere is possible
• 25% rate of failure
Anticoagulant Therapy
It is to prevent recurrent emboli formation. Immediate infu-
sion of heparin 5,000 units intravenously is helpful to prevent
further extension of thrombus. Later oral anticoagulants may
be added.
‘No re-flow’ phenomenon due to tissue oedema causes capil-
lary perfusion block. Even though compartment syndrome
and ‘no reflow’ phenomemenon are separate entities they are
always seen together along with reperfusion injury.
Metabolic acidosis, acute tubular necrosis causing acute
renal failure and cardiac arrhythmias may set in and become
life-threatening.
Features are—toxaemia; oliguria; persistent pain and
oedema in the leg with muscular tenderness; raised blood
urea and serum creatinine with features of acute ischaemia
in the limb. Raised creatinine level (renal failure), creatine
kinase (muscle lysis) are typical.
Treatment:
¾
Mannitol to prevent renal failure; fluid therapy.
¾
Fasciotomy to reduce raised compartment pressure.
All four compartments of lower limb should be decompressed surgically. Long vertical lateral deep fasciotomy
incision in the calf behind the fibula along the deep fascia
and its fibular attachments is a must. Bleeding is common
after fasciotomy as patient is heparinised. Infection of the
Complications of Revascularisation in
Acutely Ischaemic Limb
Reperfusion injury
‘No reflow’ phenomenon: It is due to severe capillary oedema
causing poor peripheral tissue hypoperfusion in spite of major
vessel revascularisation.
Acute compartment syndrome can occur due to massive
ischaemic oedema especially of skeletal muscles deep to
deep fascia which compress on venules exceeding tissue
interstitial pressure causing further compromise in tissue
perfusion.
Other complications are—sepsis, reblock, bleeding and
wound can occur. Later, once the patient is stabilised
and oedema subsides with healthy wound, secondary
suturing or skin grafting is done. If after fasciotomy,
patient survives then it is with eventual development of
Volkmann’s ischaemic contracture.
¾
Antibiotics and supportive therapy.
SADDLE EMBOLUS
It is an embolus blocking at bifurcation of aorta.
Causes: Mural thrombus after myocardial infarction; Mitral
stenosis with atrial fibrillation; Aortic aneurysm.
catheter-related complications.
REPERFUSION INJURY
It occurs after reestablishment of arterial flow to an ischemic
tissue bed which further leads to tissue death causing specifically peripheral muscle infarction. It is due to sudden release
of oxygen free radicals which blocks the microcirculation,
with release of high levels of potassium (hyperkalaemia) and
myoglobin (myoglobinaemia and myoglobinuria). Haemodynamically patient becomes unstable with lactic acidosis,
intracellular changes, interstitial oedema and cardiac dysfunction. It is often life-threatening.
Haimovici triad of revascularisation injury (1960)—(1)
Muscle infarction; (2) Myoglobinuria; (3) Acute renal failure.
Fig. 1.3 41: Saddle embolus blocking the bifurcation of abdominal aorta.
It causes severe, rapid, dramatic symptoms.
(EIA: external iliac artery; CIA: common iliac artery; IIA: internal iliac artery)
The embolus which blocks at aortic bifurcation is usually large.
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Features:
¾
Features of sudden, rapidly progressive ischaemia in
both lower limbs.
¾
Gangrene of both lower limbs.
¾
Features of associated infection.
Investigations: Arterial Doppler, aortic angiogram; Ultra-
sound abdomen.
Treatment
¾
Initially, heparin is injected intravenously—10,000 units
and later 5,000 units subcutaneously 8th hourly.
¾
Embolectomy can be done using Fogarty’s catheter.
¾
Open arteriotomy and embolectomy can also be tried.
¾
Antibiotic prophylaxis is given to prevent infection.
Note:
In aortic bifurcation thrombus, there is earlier history of claudication in the
buttock often with Leriche’s syndrome. Symptoms are slow and gradual but
not dramatic. Collaterals between aorta and iliac arteries have well-formed
and so sudden, rapid development of gangrene will not occur.
EMBOLECTOMY
Indications
¾
Acute embolic blockade of artery commonly seen in
common femoral, cranial vessels, mesenteric vessels.
¾
It should be done within 6 hours as after 6 hours irreversible changes occur—Golden hour.
B
Fig. 1.343B:
Figs. 1.343A and B: Fogarty’s catheter. It is 80 cm in length with 4 to 7
French size. It is used for embolectomy. Note the inflated balloon at the tip.
¾
It is usually done under local anaesthesia under C-arm
guidance with anaesthetist monitoring the patient. It can
be done under spinal or general anaesthesia.
Methods:
¾
Interventional method is usually employed using Foga-
rty’s catheter. Good back bleed signifies com plete ness
of embolectomy.
¾
Open arteriotomy method is done directly over the artery
followed by suturing the artery.
Complications: Bleeding; sepsis; thrombosis; narrowing;
incomplete removal.
After embolectomy: Patient is placed in ICU care; Monitoring
with—PTT, thromboplastin time.
Note:
• Intraoperative arteriogram is a must to confirm the adequacy of blood
flow and completion.
• Intraoperative thrombolysis as an adjunct to save the limb using
urokinase 2,50,000 IU for minutes into distal artery may be beneficial.
• Prophylactic fasciotomy is needed in delayed cases to prevent reperfu-
sion injury.
• Postoperative systemic heparin and later oral anticoagulant is given.
• Treatment for atrial fibrillation, atherosclerotic stenosis and other
causes is needed.
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CHAPTER 1L General Surgery: Arterial Diseases
Fig. 1.342: Embolectomy technique.
A
Fig. 1.343A:
FAT EMBOLISM (Ernst Von Bergmann, in 1873)
90% of major trauma especially with fractures develop fat
embolism from aggregation of fat globules and chylomicrons
derived from bone marrow. Fat globules release fatty acids
which act as toxins.
It is common in fracture long bones, and multiple fractures.
It is observed after intramedullary nailing, liposuction, joint
reconstruction, parenteral lipid infusion, cardiopulmonary
bypass, and pathological fractures.
Only 5–10% will develop fat embolism syndrome (FES).
FES shows respiratory distress (ARDS), and skin manifestations. Approximately 20–30% of the population have a patent
foramen ovale; fat emboli pass through the pulmonary circulation causing the systemic manifestations of FES, particularly
involving the brain and kidneys. As a result of the occluded
cerebral vasculature, patients exhibit encephalopathy, localised cerebral edema. FES has got 20% mortality.
Food is the unavoidable necessity of existence.
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¾
Features
Pulmonary: Cyanosis, tachypnoea, right heart failure, froth
in mouth and nostrils, fat droplets in sputum, eventually
respiratory failure.
Cutaneous: Petechial haemorrhages in the skin.
Cerebral: Drowsy, restlessness, disoriented, constricted
pupils, pyrexia and coma.
Retinal artery emboli is the earliest sign to appear, causing
striae haemorrhages, fluffy exudates confirmed on fundo-
scopic examination.
Kidney: Blockage in renal arterioles results in fat droplets
SRB’s Manual of Surgery
in urine.
Gurd and Wilson criteria for FES
T
Major criteria Minor criteria
• Symptoms and radiologic
evidence of respiratory
insufficiency
• Cerebral sequelae unrelated to
head injury or other conditions
• Petechial rash—over upper
body, axillae
Differential diagnosis: Pulmonary embolism; Thrombotic
• Tachycardia (heart rate
>110/min)
• Pyrexia (>38.5°C)
• Retinal changes or
petechiae
• Renal dysfunction
• Jaundice
• Acute drop in hemoglobin
level
• Sudden thrombocytopaenia
• Elevated erythrocyte
sedimentation rate
• Fat microglobulinaemia
thrombocytopenic purpura.
Investigations:
¾
Presence of fat lobules in the blood obtained by pulmonary capillary wedging is diagnostic.
¾
Haemoglobin estimation, platelet count and total WBC
count.
¾
Chest X-ray shows snow storm appearance.
¾
CT chest is useful; CT head is done to rule out causes of
intracranial injuries.
¾
Transesophageal echocardiography (TEE) may be of
use in evaluating the intraoperative release of marrow
contents into the bloodstream during intramedullary
reaming and nailing.
¾
Bronchoalveolar lavage with staining for fat will show
lipid inclusions.
Treatment:
¾
Adequate oxygenation with ventilator support (ICU care).
¾
Hydration, nutrition, achieving haemodynamic stability,
prevention of DVT, avoiding volume overload with proper
fluid therapy.
¾
Methylprednisolone may be useful; but use of heparin,
low molecular dextran and other steroids are controversial even though commonly used.
¾
Albumin transfusion may be helpful as it binds with fatty
acids to reduce the lung injury.
Early fixation of the fractures; placement of IVC filters will
prevent the chances of fat embolism or emboli reaching
into the lungs.
AIR/GAS EMBOLISM
Causes
Through venous access like IV cannula, most common cause.
During artificial pneumothorax.
During surgeries of neck and axilla.
Traumatic opening of major veins sucking air inside, causing
embolism.
During fallopian tube insufflation; laparoscopic surgeries.
During illegal abortion.
Features
It causes respiratory distress, haemoptysis, convulsions,
unconsciousness, visual and hearing disturbances, fatigue and
numbness, paralysis, haemodynamic instability and coma.
x Amount of air required causing venous air/gas embolism is 15
m
L. To precipitate symptoms in venous embolism 100 mL of air
required. 100 m
x When the air enters the right atrium, it gets churned up forming
foam which enters the right ventricle and blocks the pulmonary
artery.
x Mill-Wheel murmur (machinery) heard over the precordium
through a stethoscope is diagnostic.
x During open heart surgery/therapeutic pneumothorax, by acci-
dental pulmonary vein puncture or in atrial septal defect (ASD)
air may enter left side of the heart (paradoxical air embolism)
causing coronary block or cerebral air embolism.
x Arterial gas embolism is more dangerous and often early fatal.
2 m
L of gas/air is fatal in cerebral circulation; and 0.5 mL is fatal
in coronary arteries.
x Through paravertebral veins also air embolism to brain can occur.
L of air at a rate more than 100 mL/second is fatal.
Treatment
Patient is placed in Trendelenburg left lateral decubitus
position. The Trendelenburg position keeps left ventricular
air bubble away from the coronary artery ostia (which are
near the aortic valve) so that air bubbles do not enter and
occlude the coronary arteries. Left lateral decubitus positioning helps to trap air in the non-dependent segment of
the right ventricle (where it is more likely to remain instead
of progressing into the pulmonary artery and occluding
it). The left lateral decubitus position also prevents the air
from passing through a potentially patent foramen ovale
(present in as many as 30% of adults) and entering the
left ventricle, from which it could then embolise to distal
arteries.
Hyperbaric oxygen is useful in both venous and arterial
gas/air embolism as it reduces the ischaemia, reduces
the bubble size; in arterial gas embolism it removes the
nitrogen from the bubble so that to improve perfusion and
oxygenation.
By passing a needle, the air has to be aspirated from the
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right ventricle. Often requires life-saving open thoracotomy
to aspirate the excess air causing the block.
THERAPEUTIC EMBOLISATION
Indications
Haemangiomas; AV fistulas.
Malignancies like renal cell carcinoma, hepatoma.
Cerebrovascular problems.
To arrest haemorrhage from GIT, urinary and res piratory tract.
¾
In bleeding duodenal ulcer or gastric ulcer, embolisation
is done to occlude gastroduodenal artery or left gastric
artery respectively.
¾
It is also useful in bleeding oesophageal varices, secondaries in liver (mainly due to carcinoids), hepatoma.
MATERIALS USED FOR THERAPEUTIC EMBOLISATION
B
x Blood clot
x Gel foam
x Balloons
x Quick setting plastics
x Stainless steel coils
x Human dura
x Plastic microspheres
x Ethyl alcohol
x Wool
False aneurysm contains single layer of fibrous tissue as wall
of the sac and it usually occurs after trauma.
TYPES
B
x Fusiform—uniform dilatation of entire circumference of arterial
wall
x Saccular—dilatation of part of circumference of the arterial wall
x Dissecting—through a tear in the intima blood dissects between
inner and outer part of tunica media of the artery
Fig. 1.344: True and false aneurysms. In true type, all layers are intact.
In false type all layers breached with haematoma having a false capsule.
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CHAPTER 1L General Surgery: Arterial Diseases
CAISSON’S DISEASE OR DECOMPRESSION DISEASE
(BEND’S DISEASE)
It occurs due to rapid decompression from high altitude, aircraft,
compressed air chambers, deep sea divers causing bubbling of
nitrogen which blocks the small vessels.
It is classified as TypeI/(Simple) involving musculoskeletal
system, skin, lymphatics and Type II (Serious) involving also
major organs. Commonest part involved is musculoskeletal
system (90%) mainly major joints like elbow, shoulder, hip,
wrist, knee and ankle.
In joints and muscles it causes excruciating pain (bends).
Spinal cord ischaemia causing neurological deficits.
Lungs may be affected causing choking with chest pain,
tightness and dry cough.
Treatment:
¾
Oxygen therapy; Recompression and gradual decompression in special chamber.
ANEURYSM
There is no disease more conducive to clinical humility than aneurysm
of the aorta. —William Osler, Circa 1900
It is an abnormal permanent dilatation of localised segment
of arterial system. Diameter will be 50% more than expected
normal diameter of that artery in aneurysm. Atherosclerosis
which is the most common (90%) facilitating cause of
aneurysm is due to destruction and loss of stability of tunica
media.
True aneurysm contains all three layers of artery.
Fig. 1.345: Fusiform and saccular types of aneurysms.
Fig. 1.346: Thoracic aortic aneurysm.
When you cease to dream, you cease to live.
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Causes
¾
Acquired:
–
–
Degenerative: Atherosclerosis (most common
cause— 90%); mucoid degeneration of intima and
media (in South African young Negroes).
Traumatic: Direct; indirect like in post-stenotic dilata-
Distal oedema due to venous compression.
Altered sensation due to compression of nerves.
Erosion into bones, joints, trachea or oesophagus.
Aneurysm with thrombosis can throw an embolus causing
gangrene of toes, digits, extending often proximally also.
tion by cervical rib; traumatic AV aneurysmal sac;
aneurysm due to irradiation (due to dryness and
destruction of vasa vasorum causing weakening).
–
Infective: Syphilis; mycotic; tuberculosis (in lung);
arteritis; acute sepsis.
–
Collagen diseases like Marfan‘s syndrome, polyarte-
SRB’s Manual of Surgery
Sites: Aorta; Femoral; Popliteal; Subclavian; Cerebral, mesen-
ritis nodosa, Ehler-Danos syndrome.
¾
Congenital:
–
Berry aneurysm; cirsoid aneurysm; congenital AV fistula.
teric, renal, splenic arteries.
The most common is true, fusiform, atherosclerotic, aortic
aneurysms.
Berry aneurysms are multiple aneurysms occurring in circle
of Willis.
EFFECTS AND COMPLICATIONS OF ANEURYSM
B
x Thrombosis and distal ischaemia
x Release of emboli causing acute arterial occlusion
x Pressure effects on bone (erosion); skin; veins (oedema);
nerves (pain, paraesthesia); stomach (erosion—haematemesis);
oesophagus (dysphagia)
x Rupture; Infection of aneurysm
Clinical Features of Aneurysms
Swelling at the site which is pulsatile (expansile), smooth,
soft, warm, compressible, with thrill on palpation and bruit
on auscultation. Swelling reduces in size when pressed
proximally.
Fig. 1.347: Chest X-ray showing aortic aneurysm.
Differential Diagnosis
Pyogenic abscess: Abscess has to be always con firmed by
aspiration; especially in axilla, popliteal region, groin.
Vascular tumours.
Pulsating tumours: Sarcomas, pulsating secon daries.
Pseudocyst of pancreas mimics aortic aneurysm.
AV fistula.
A B
Figs. 1.348A to C: Different methods of aneurysm repair. (A) Matas aneurysmorrhaphy for saccular aneurysm; (B) Excision and Dacron grafting; (C)
Ligation and exclusion of the aneurysm using autologous vein graft and excision of aneurysm and bypass using autologous vein graft.
C
Investigations
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Doppler study, duplex scan, CT angiogram, DSA.
Tests relevant for the cause, like blood sugar, lipid profile,
echocardiography.
Fig. 1.349: Right renal artery aneurysm on CT angiogram.
Fig. 1.350: Cerebral CT angiogram showing (intracranial)
Berry’s aneurysm.
Treatment
branch—Wardrop’s; ligature one proximal and another distal
to aneurysmal sac—Antylus’).
MYCOTIC ANEURYSM (INFECTIVE ANEURYSM) (3%)
It is a misnomer. It is mushroom shaped aneurysm, hence
the name (William Osler, 1885).
It is not due to fungus but due to bacterial infection of the
arterial wall. It is actually an endovascular infective vasculitis.
Common bacteria are gram positive organisms like Staphylo-
coccus aureus (most common) and Streptococcus. Salmo-
nella infection also can cause infective aortic aneurysm.
Infective aortic aneurysm is common in Taiwan.
Common aetiology is bacterial endocarditis but could be any
infective site. Cholecystitis, urinary infection, osteomyelitis,
diverticulitis and pneumonia also occasionally cause infective aneurysm.
It is seen in diseased atherosclerotic artery (like aorta) or
traumatized disrupted intima of the artery (femoral).
Common vessels involved are aorta, visceral, head and neck
and intracranial.
Commonly it is saccular, multilobed, with a narrow neck.
Patient presents with fever, back pain (if aorta), toxaemia and
tender pulsatile mass if it is in the periphery.
Torrential haemorrhage and sepsis can occur as complica-
tion. It has got 50% mortality.
Investigations: Leucocytosis and raised ESR; positive blood
culture (70% cases), positive culture from aneurysmal sac,
MR or CT angiogram are relevant.
Treatment: Broad-spectrum antibiotics (often for long term,
>6 weeks); resection of the aneurysm; debridement and
drainage of the infected aneurysm with adequate blood transfusions; extra -anatomic bypass through uninfected tissue
planes to avoid contamination of the graft. Endovascular
aneurysm repair (EVAR) often with covered endovascular
reconstruction of aortic bifurcation (CERAB) is becoming
more commonly used nowadays as less invasive effective
therapy.
Note:
Microbial arteritis with aneurysm is a different entity is due to bacteraemia
occurring in an athero sclerotic vessel due to Salmonella infection.
191
CHAPTER 1L General Surgery: Arterial Diseases
Reconstruction of artery using arterial grafts.
Arterial endoaneurysmorrhaphy—MATAS. It is done usually
for peripheral saccular aneurysm. Matas aneurysmorrhaphy
may be restorative or endo-obliterative or reconstructive.
Therapeutic embolisation.
Clipping the vessel under guidance (e.g. cranial aneurysms).
Older methods which are now not used but popular earlier
were—wiring of the aneurysmal sac/wrapping of the aneu-
rysmal sac/ligatures at different levels (ligation just proximal
to aneurysmal sac—Anel’s; ligation proximally proximal to
an arterial branch—Hunter’s; ligation just distal to aneu-
rysmal sac—Brasdor’s; ligation distally distal to an arterial
ABDOMINAL ANEURYSM
Abdominal aortic aneurysm is the most common aortic aneu-
rysm. Splenic artery aneurysm is the 2nd most common type.
Incidence is 2%. It is more common in males.
Transverse diameter of aorta in an aneurysm should be
3 cm or more.
Common in elderly; common in males (4:1); chance of getting
aneurysm in genetically related first degree relatives is 10
times more.
Common in smokers (8:1 with nonsmokers); in 55% of
patients Chlamydia pneumoniae is identified.
Today’s impossibilities are tomorrow’s miracle.
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ABDOMINAL AORTIC ANEURYSM (AAA)
AAA is a localised, progressive and permanent dilatation usually
larger than 3 cm in diameter of the abdominal aortic wall.
Causes
Atherosclerosis (as degenerative process) is the most
common facilitating cause (95%)—aortic wall contains
smooth muscle cell matrix, elastin, collagen; elastin (in
tunica media) is the main load bearing part with collagen (in
adventitia) as safe net in the wall to provide tensile strength
preventing aneurysm formation. Elastin in medial layer of
SRB’s Manual of Surgery
aorta is degraded and reduced significantly in infrarenal
aorta in relation to collagen, absence or less vasa vasorum in
infrarenal aorta and atherosclerotic unstability of the medial
wall of aorta cause infrarenal aorta more prone to develop
aneurysm. Increased proteolytic activity of aortic medial wall
due to increased matrix metalloproteinases (MMP) (derived
from aortic smooth muscle cells and macrophages) cause
elastin and collagen degradation and increase in diameter of
aneurysm. Collagen degradation in adventitia causes rupture.
Familial aortic aneurysm (associated with 25% of AAA) is
more prevalent in females to reduce male-to-female ratio to
2:1. It is related to decrease in type III collagen, α1 antitrypsin
and lysyl oxidase. Marfan’s, Ehler Danlos syndromes are
related genetically.
Others: Syphilis, dissection, trauma, collagen diseases,
infection, arteritis, cystic medial necrosis, association with
Chlamydia pneumoniae (55%).
x Classification I
– Infrarenal—most common (95%).
– Suprarenal—5%. Isolated suprarenal type is rare; it is usually
associated with thoracic and or infrarenal types.
x Classification II
– Asymptomatic.
– Symptomatic.
– Symptomatic ruptured.
Asymptomatic Type
It is found incidentally either on clinical examination or on
angiography or on ultrasound.
Repair is required if diameter is over 5.5 cm on ultrasound.
It is identified during routine abdominal palpation or while
assessing or operating for some other abdominal conditions.
In infrarenal type upper border is clearly felt.
Lower limb ischaemia and embolic episodes can occur.
Being a retroperitoneal mass back pain is common—may be
due to retroperitoneal stretching, nerve irritation or vertebral
erosion.
5% present as inflammatory aneurysm adherent to ureters,
left renal vein, inferior vena cava and duodenum. Expanding
aneurysm blocks lymphatics causing inflammation and
fibrosis; or it may be due to infection and fibrosis of earlier
localised ruptured abdominal aortic aneurysm. Such chronically inflamed aneurysm will not rupture further; but it is
always symptomatic with fever and severe pain in abdomen
and back. It needs surgical repair through retroperitoneal
approach.
Aortocaval fistula, presents as high output cardiac failure with
continuous bruit in abdomen and severe lower limb ischaemia
(steal phenomenon).
Aortoenteric fistula is due to erosion of aneurysm into 4th
part of duodenum presenting as gastrointestinal (GI) bleed,
malaena, shock. It is treated by duodenal closure, aortic ligation, aneurysmal exclusion with extra-anatomic bypass graft
with gastrojejunostomy. Contamination is the major threat
here.
Aneurysm in a patient with horseshoe kidney which is
anterior to aorta is difficult to manage. Left retroperitoneal
approach is needed. Endovascular aneurysm repair (EVAR)
is not possible.
Investigations
Blood urea, serum creatinine.
US (most widely used noninvasive test; but neck of the aneu-
rysm, dimensions and relation to renal arteries are difficult to
assess), aortogram, DSA, CT scan (most precise). US is an
effective screening tool. Screening is done in cardiovascular
patients in men (60–85 years), in women (60–85 years); men
and women above 50 years with family history; annually in
asymptomatic AAA with 4.0–4.5 cm size, with size >4.5 cm
once in every 6 months.
CT angiogram, MR angiogram.
Blood sugar, lipid profile, other relevant investigations like
ECG, echocardiography, cardiac and pulmonary assessment.
Symptomatic without Rupture
(Clinical features/presentations)
It presents as back pain, abdominal pain, mass abdomen
which is smooth, soft, nonmobile, not moving with respira-
tion, vertically placed above the umbilical level, pulsatile both
in supine as well as knee-elbow position with same intensity,
resonant on percussion.
Common in males (4:1); common in smokers.
GIT, urinary, venous symptoms can also occur.
Hypertension, diabetes, cardiac problems should be looked
for and dealt with.
Note:
X-ray will show eggshell calcification. CT scan is more reliable and precise
investigation of choice—gives better information regarding extent on sides/
neck, size, dimensions, size and site of the thrombus, calcification, relation
of renal arteries, inflammation and fibrosis and adjacent tissues. MRI may
be better only in renal failure patients.
COMPLICATIONS OF ABDOMINAL AORTIC ANEURYSM
B
x Rupture, infection
x Thrombosis, embolism, distal ischaemia/gangrene
x Aortocaval fistula, aortoenteric fistula formation
x Erosion of vertebra, spinal cord ischaemia when thrombosis
develops
impairment and noninflammatory aneurysm); if aneurysm
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size is <5 cm; if growth rate is <0.5 cm/year.
It includes risk factor modifications; stopping smoking;
control of blood pressure (propranolol), cholesterol; usage
of drugs—alpha blockers, elastase inhibitors (NSAID—
indomethacin), matrix metalloproteinases (MMP) inhibitor
(doxycycline).
Periodic size measurement of an aneurysm using ultrasound
once in 6 months to find out growth rate is essential during
conservative treatment.
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CHAPTER 1L General Surgery: Arterial Diseases
A
B
Figs. 1.351A and B: USG abdomen showing abdominal
aortic aneurysm.
Fig. 1.352: Abdominal aortic aneurysm showing widened aortic wall
with thrombosis in the periphery in CT angiogram.
Differential Diagnosis
Retroperitoneal mass, pseudocyst of pancreas, retroperito-
neal cyst mimic abdominal aortic aneurysm especially when
it is thrombosed.
Mesenteric ischaemia, acute pancreatitis, perforated duodenal
ulcer may mimic ruptured aneurysm.
Other conditions causing back pain like disc prolapse, sciatica.
Treatment
Conservative/Medical Treatment
It is done in low-risk abdominal aortic aneurysm (age below
70 years; active physically without cardiac, respiratory, renal
Surgical Treatment
Indications for surgery
¾
Asymptomatic aneurysm more than 5.5 cm.
¾
Growth rate more than 0.5 cm/year.
¾
Painful, tender aneurysm.
¾
Thrombosed aneurysm, aneurysm with distal emboli.
Low-risk, intermediate-risk and high-risk of abdominal
T
aortic aneurysm
Low-risk abdominal aortic aneurysm—age below 70 years; active
physically without cardiac, respiratory, renal impairment and
noninflammatory aneurysm. Here surgical mortality is <3%.
Intermediate-risk—sedentary; stable coronary disease; mild COPD;
creatinine 2–3 mg%; inflammatory/suprarenal aneurysm. Here
surgical mortality is 3–7%.
High-risk—restricted daily works; significant coronary disease;
dyspneic COPD; creatinine >3 mg%; liver failure status. Here
surgical mortality is >10%.
Open surgical repair
¾
It is called as endo-aneurysmorrhaphy with intraluminal
graft placement (Crawford, 1960). It is done under GA
with epidural support. Major challenges during anaesthesia are—blood loss, haemodynamic control, problems
during clamping and declamping of aorta, temperature
control, renal hypoperfusion, left ventricular strain.
¾
Incision is commonly lengthy midline transperitoneal or
supraumbilical transverse. Retroperitoneal approach is used
in horseshoe kidney, abdominal wall stoma, inflammatory
aneurysm, suprarenal extension, peritoneal dialysis, hostile
abdomen. Retroperitoneal approach favors rapid control
of proximal aorta but prevents visualisation of abdomen.
¾
After laparotomy, duodenum and small bowel are
retracted laterally and above; left renal vein which is in
front of aorta is dissected and retracted; occasionally
it may require to be ligated and it is safer provided left
gonadal and left suprarenal veins are intact. Distal arterial
clamps are applied first along common or external and
internal iliac arteries on both sides. Proximal aortic clamp
is applied at infrarenal level. Aorta is opened longitudinally
midline towards right to avoid injury to orifice of inferior
mesenteric artery. Atheroma, thrombus is removed until
A positive thought is a seed of positive result.
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adequate back-bleeding occurs. Lumbar vessels are
ligated from the luminal side. Knitted Dacron graft after
preclotting or woven Dacron graft or ePTFE tube graft is
used. Graft is anastomosed above and below using polypropylene sutures (4-zero). Inferior mesenteric artery can
be reimplanted. Clamps are released first below. Colonic
and limb perfusion is checked for adequacy. Graft is
covered with aneurysmal sac.
¾
Minimal incision aortic surgery (MIAS) is done in thin
individual with midline abdominal incision 12 cm in length
with its 9 cm part above the umbilicus. Specialised retrac-
SRB’s Manual of Surgery
tors and vascular clamps are used for this. Advantages
are less postoperative pain, ileus and incisional hernia.
Endovascular aneurysm repair (EVAR)
¾
In 1991 Juan Parodi and Julio Palmaz first did EVAR. It
B
Aorto bifemoral dacron graft (Woven) with right femoral exposed
is less invasive, less morbid with less mortality rate and
shorter hospital stay. It is basically aneurysm exclusion
method. It is useful in old age and patients who are not fit
for surgery. EVAR is basically a prophylactic procedure.
EVAR is indicated if aneurysm is less than 5.5 cm in
men and less than 5.0 cm in women. It is usually done
in patients after 65 years (Figs. 1.355A and B).
¾
It is endoluminal stent graft placement into the aneurysmal segment of aorta using interventional radiology
with Seldinger’s technique approach through femoral
artery.
¾
Dacron or ePTFE with integral metallic stent for support
C
Graft in place in retroperitoneum
Figs. 1.353B and C
Figs. 1.353A to C: Abdominal aortic aneurysm with aortofemoral graft
placement (Courtesy: Dr Ashok Shetty,
Mangaluru).
MCH, Cardiothoracic Surgeon,
and firm attachment is used as stent/endovascular
prosthesis.
¾
One aortic and iliac (of one/same side) stent is commonly
used together which is passed through same side
common femoral. Other iliac is maintained with a separate
stent approached through opposite common femoral.
¾
Procedure can cause endoleak, thrombosis, embolism,
malposition/displacement of stent, sigmoid ischaemia,
renal failure, failure of stent function causing recurrence
and infection.
Symptomatic Ruptured Aortic Aneurysm
Risk of rupture is 1%, if diameter is within 5.5 cm in size.
Risk increases to 20% once the diameter = 7 cm.
It may be anterior rupture (20%) into the free peritoneal cavity
causing severe shock and death very early; or posterior rupture
(80%) with formation of retroperitoneal haematoma of large
size causing severe back pain, hypotension, shock, absence of
femoral pulses and with a palpable mass in the abdomen.
Management of ruptured aortic aneurysm
¾
Immediate diagnosis by ultrasound.
¾
Resuscitation.
¾
Massive blood transfusions (10–15 bottles).
¾
Emergency surgery is the only life-saving pro cedure in
these cases.
Patient has to be shifted to the operation theatre. Abdomen is
opened. Vascular clamps or bull dog clamps are applied to the
aorta above and below the aneurysm. Adventitia is opened and
the clot is removed. Aneurysm is excised and the arterial graft
either PTFE (Polytetra fluoroethylene), knitted Dacron graft, or
woven dacron graft is placed. The graft is sutu red to the vessel
A
Fig. 1.353 A
above and below using monofilament, nonabsorbable suture
material, polypropylene 5-zero.
Fig. 1.354: Infrarenal aortic aneurysm repair. It is the most common site of aortic aneurysm. Adventitia of aorta is opened; aneurysm is excised;
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graft is sutured above and below; adventitia is wrapped around.
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CHAPTER 1L General Surgery: Arterial Diseases
A B
Figs. 1.355A and B: Endovascular aneurysm repair (EVAR). Aortic and one side iliac stent is used as one unit modulus which is passed
through same side common femoral artery; opposite side iliac part is inserted as separate modulus through opposite CFA.
COMPLICATIONS OF SURGERY
B
x MI is the most common cardiac complication in perioperative and
in first 2 days of postoperative period
x Haemorrhage and haemodynamic complications
x Renal failure—is most common noncardiac complication
x Colonic ischaemia—10% due to poor IMA circulation
x Sexual dysfunction
x Aortoduodenal fistula; Aortovenacaval fistula
x Spinal cord ischaemia—paraplegia
x Paralytic ileus
x Distal thromboembolism—blue toe syndrome
x DVT, limb ischaemia
x Graft leak, graft thrombosis, graft failure
x Anastomotic disruption, pseudoaneurysm formation
x Prosthetic infection/migration
REMEMBER
B
x Pulsation of an aneurysm is expansile. Pulsation may be absent
if it is thrombosed
x Abdominal aneurysm of any size which is painful or tender should
be operated
x Abdominal aortic aneurysm of any size causing embolus should
be operated
x Abdominal aortic aneurysm more than 5.5 cm should be operated
x In ruptured abdominal aortic aneurysm emergency surgery is the
only choice operation with rapid resuscitation; immediate opening
and repair using graft. Systolic pressure in this patient should be
just adequate to maintain the cardiac function but should not be
more than 100 mmHg as it will cause more bleeding
x Anterior rupture is more dangerous than posterior rupture
x Endoluminal stenting is becoming popular
Move to the rhythm of soul and you’ll never miss a beat.
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