Pathophysiology 3
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Transcript of Pathophysiology 3
Admission Diagnosis:
Acute abdomen secondary to gunshot wound 0.5cm point of entry left flank with
no point of exit, gunshot wound, left scapular area with no point of exit
Principal Diagnosis:
Acute abdomen secondary to gunshot wound 0.5 cm point of entry left Flank with
Grade II Splenic Injury; Grade III Pancreatic Injury Tail; Grade II Descending Colon In-
jury; Splenic Artery Complete Transection with mild Hemoperitoneum
A gunshot wound (GSW) is caused by a missile propelled by combustion of powder.
These wounds involve high-energy transfer and, consequently, can involve an unpre-
dictable pattern of injuries. Secondary missiles, such as bullet and bone fragments, can
inflict additional damage. Military and hunting firearms have higher missile velocity than
handguns, resulting in even higher energy transfer.
The severity of shotgun wounds depends on the distance of the victim from the weapon.
The mass of a shot pellet is minimal, and thus its velocity decreases rapidly after the
shell leaves the barrel of the gun. When the distance is less than 3 yd, the injury is con-
sidered high velocity; if the distance exceeds 7 yd, most of the buckshot penetrates only
the subcutaneous tissue.
Abdomen
The abdomen contains
most of the tube-like organs of
the digestive tract, as well as
several solid organs. Hollow ab-
dominal organs include the stomach, the small intestine, and the colon with its at-
tached appendix. Organs such as the liver, its attached gallbladder, and the pan-
creas function in close association with the digestive tract and communicate with it via
ducts. The spleen, kidneys, andadrenal glands also lie within the abdomen, along with
many blood vessels including the aorta and inferior vena cava. Anatomists may consider
the urinary bladder, uterus, fallopian tubes, and ovaries as either abdominal organs or as
pelvic organs. Finally, the abdomen contains an extensive membrane called theperi-
toneum. A fold of peritoneum may completely cover certain organs, whereas it may
cover only one side of organs that usually lie closer to the abdominal wall. Anatomists
call the latter type of organs retroperitoneal.
Digestive tract: Stomach, small intestine, large intestine with cecum and appendix
Accessory organs of the digestive tract: Liver, gallbladder and pancreas
Urinary system: Kidneys, ureter, urinary bladder and urethra
Immune system: Spleen
FlankThe flank is the
area between the anterior and posterior axillary lines, superiorly bordered by the sixth
rib and inferiorly bordered by the iliac crest. Although a penetrating wound to the flank
can produce intraperitoneal injury with the associated physical examination findings of
peritonitis or hemoperitoneum with shock, it is possible that a penetrating flank wound
only injure the retroperitoneal organs.
A delay in diagnosis of duodenal, colonic, rectal, renal, pancreatic, or major vas-
cular injuries may result in delayed septic or hemorrhagic shock. The path of a gunshot
or stab wound to the flank may track superiorly. Bullets may ricochet off the bony struc-
tures of the spine and produce a unique bullet path and injury pattern. Other intra-ab-
dominal organs may be injured such as the stomach, pancreas, diaphragm, and in-
trathoracic organs. Inferior tracking will jeopardize the lower GI tract and colon.
Spleen
The spleen is an organ shaped like a shoe that lies relative to the 9th and 11th
ribs and is located in the left hypochondrium and
partly in the epigastrium. Thus, the spleen is situ-
ated between the fundus of the stomach and the
diaphragm. The spleen is very vascular and red-
dish purple in color; its size and weight vary. A
healthy spleen is not palpable.
Functions of the Spleen
Immune responses
After antigenic stimulation, increased for-
mation of plasma cells for humoral responses and
increased lymphopoiesis for cellular responses
occurs.
Phagocytosis
One of the spleen's most important functions is phagocytosis. The spleen is a
component of the reticuloendothelial system. The splenic phagocytes include reticular
cells, free macrophages of the red pulp, and modified reticular cells of the ellipsoids.
Phagocytes in the spleen remove debris, old and effete red blood cells (RBCs), other
blood cells, and microorganisms, thereby filtering the blood. Phagocytosis of circulating
antigens initiates the humoral and cellular immune responses.
Hematopoiesis
The spleen is an important hematopoietic organ during fetal life; lymphopoiesis contin-
ues throughout life. The manufactured lymphocytes take part in immune responses of
the body. In the adult spleen, hematopoiesis can restart in certain diseases such as
chronic myeloid leukemia and myelosclerosis.
Storage of red blood cells
The RBCs are stored in the spleen. Approximately 8% of the circulating RBCs are
present within the spleen; however, this function is seen better in animals than humans.
. Spleen is 1 inch thick, 3 inches broad and 5 inches long. The enlargement of
spleen is referred to as splenomegaly.
Tail of Pancreas
The tail of the pancreas, located
anatomically left near the hilum of the spleen, is not simply an anatomical distinction.
The tail[disputed – discuss] is the only part of the pancreas which contains Pancreatic
Polypeptide (PP) cells, which are responsible for secreting pancreatic polypeptide to
coordinate exocrine and islet enzyme release. PP cells are found in the tail's periph-
ery. Beta cells (insulin secretory) and delta cells (somatostatin secretory) are found in
the central part of the tail as with the rest of the pancreas.
The cells described above are located exclusively in the islet cells; their secre-
tions reach exocrine portions of the pancreas via the capillary network surrounding the
islet cell populations.
De-
scend- ing
Colon
The descending colon is a segment of the large intestine and is the third and
penultimate segment of the colon. It transports feces from the transverse colon inferiorly
along the left side of the abdominal cavity to the sigmoid colon. Feces passing through
the descending colon are stored until they are ready to be eliminated from the body.
The walls of the descending colon absorb water as well as remaining nutrients and vita-
mins from the feces, depositing these valuable substances into our bloodstream
The descending colon is a hollow tube that is part of the gastrointestinal (GI)
tract. Its diameter is roughly 2.5 inches (7 cm), while its length is approximately 9 to 10
inches (25 cm). It contains many small pouches, known as haustra, along its length that
increase its surface area and help to move feces through the colon. At its superior end,
the descending colon connects to the transverse colon at the splenic flexure just inferior
to the spleen. From the splenic flexure, the descending colon extends inferiorly toward
the left hip before turning about 90 degrees to the right and forming the sigmoid colon.
Like all parts of the gastrointestinal tract, the descending colon consists of four
major tissue layers surrounding a hollow lumen. The mucosa forms the innermost layer
that surrounds the lumen and is in contact with fecal matter stored in the colon. Mucosa
is a mucous membrane made of simple columnar epithelial tissue and a thin underlying
layer of areolar connective tissue. The mucus secreted from goblet cells in the mucosa
layer provides lubrication to feces moving through the lumen, protecting the delicate tis-
sues of the colon. Epithelial cells in the mucosa absorb any remaining nutrients, vita-
mins, and water present in the feces. Surrounding the mucosa are the supportive tis-
sues of the submucosa layer, where we find blood vessels, nerves and connective tis-
sues. The muscularis layer is found deep to the submucosa and enables movement of
the descending colon. Several layers of smooth muscle make up the muscularis and al-
low the descending colon to form the pocket-like haustra. During defecation, these mus-
cle cells contract in waves of peristalsis to push feces down the colon toward the sig-
moid colon. Finally, the outermost anterior layer of the descending colon is visceral peri-
toneum; on the posterior of the descending colon, the outermost layer is areolar con-
nective tissue (known as adventitia). These tissues anchor the colon along the posterior
body wall; provide blood flow to the colon; and offer protection from friction as our bod-
ies move.
By the time feces reach the descending colon, the vast majority of nutrients, vita-
mins and water have been extracted by the ascending and transverse colon, leaving
mostly waste products. Still, some absorption of water and vitamins produced by bacte-
rial fermentation of feces – including vitamins K, B1, B2 and B12 – does occur in the de-
scending colon. Its primary function, however, is the storage and accumulation of feces
prior to defecation. During defecation, the descending colon helps to propel feces to-
ward the sigmoid colon and rectum and eventually out of the body by contraction of its
smooth muscle tissue.
Splenic Artery
The splenic artery is, along with the gastric and common hepatic arteries, one of
the three main branches of theceliac artery. The celiac artery branches from the abdom-
inal aorta, the largest artery in the abdomen.
The splenic artery is responsible for supplying oxygenated blood to the spleen,
but also has several branches that deliver blood to the stomach and pancreas. The
branches of the splenic artery are the short gastric, the left gastroepiploic, the posterior
gastric, and the branches to the pancreas.
The short gastric arteries consist of five to seven small branches that run along
the greater curvature of the stomach.
The left gastroepiploic artery is the largest branch of the splenic artery and runs toward
the interior of the stomach through the greater omentum, a large membrane that hangs
down from the stomach.
The branches to the pancreas consist of numerous, small, blood vessels that run
behind the upper border of the pancreas, supplying it with blood.
Large volumes of blood lost before signs and symptoms manifest
Blast Injury – Gunshot: point of entry left flank
Trauma to left flank
Injury to the abdominal wall – penetrating trauma may appear minimal externally in com-
parison to internal trauma. Muscle may mask the size of the external wound
Injury to the spleen:
Grade II• Subcapsular haematoma 10-50% of surface area• Intraparenchymal haematoma <5 cm in diameter• Laceration 1-3 cm depth not involving trabecular vessels
S/S•Abdominal pain and tenderness.•Bleeding, swelling, or bruising from the wound site.•Burned skin caused by a gun fired at close range.•Open wounds where the objects may have entered or exited.•Pain on the left shoulder.
• Signs of shock including a fast pulse (heartbeat), low blood pressure, and pale skin.
Injury to Tail of PancreasGrade III - Distal transection
---- S/S
Injury to Descending Colon Grade II - Laceration <50% of circumference----- S/S