Anatomy of Surgical Incisions Flashcards
What are some common O & G incisions?
Lower segment C-section = suprapubic incision
Laparotomy = vertical midline incision
Laparoscopy = subumbilical incision
Abdominal hysterectomy = vertical midline incision
Where do the external obliques attach?
Attach between lower ribs and iliac crest, pubic tubercle and linea alba
What direction do the fibres of the external obliques go in?
Fibres run in same direction as external intercostals
Where do the internal obliques attach?
Attach between the lower ribs, thoracolumbar fascia, iliac crest and linea alba
What direction do the fibres of the internal obliques go in?
Fibres run in same direction as internal intercostals
What are the attachments of the transversus abdominis?
Attach between lower ribs, thoracolumbar fascia, iliac crest and linea alba
What is the purpose of the tendinous intersections of the rectus abdominus?
Divide each rectus abdominis into 3 or 4 smaller muscles
What forms the linea alba?
Interweaving of muscle aponeuroses = runs from xiphoid process to pubic symphysis
Where is the rectus sheath located?
Immediately deep to superficial fascia
What is the rectus sheath?
Combined aponeuroses of anterolateral abdominal wall muscles
What does the rectus sheath surround?
Rectus abdominis muscles
How is the rectus sheath incised during a suprapubic incision?
Incised anyeriorly
Where does the nerve supply of the anterolateral abdominal wall enter from?
Enters from the lateral direction
What is the nerve supply to the anterolateral abdominal wall?
7th-11th intercostal = become thoracoabdominal nerves
Subcostal (T12), iliohypogastric (L1), ilioinguinal (L1)
What is the blood supply to the anterior abdominal wall?
Superior epigastric arteries and inferior epigastric arteries
What are some features of the superior epigastric arteries?
Continuation of the internal thoracic arteries
Emerge at superior aspect of abdominal wall
What are some features of the inferior epigastric arteries?
Branch of the external iliac artery
Emerge at inferior aspect of the abdominal wall
What is the blood supply of the lateral abdominal wall?
Intercostal and subcostal arteries = continuations of posterior intercostal arteries, emerge at lateral aspect
What are the principles when incising muscle?
Minimise traumatic injury to muscle fibres = incise in same direction as muscle fibre
Avoid damaging nerves and interrupting blood supply
How is a lower segment C-section carried out?
Rectus muscle not cut = separated from each other in lateral direction
What are the layers encountered when opening during a lower segment C-section?
Skin and fascia, anterior rectus sheath, rectus abdominis, fascia and peritoneum, (retract bladder), uterine wall, amniotic sack
What are the layers that have to be stitched closed after a lower segment C-section?
Uterine wall with visceral peritoneum, rectus sheath, skin
What are the layers encountered when opening during a laparotomy?
Skin and fascia, linea alba, peritoneum
What are the layers that have to be stitched closed after a laparotomy?
Peritoneum and linea alba, fascia skin
What kind of incision is used for a laparotomy?
Midline incision = relatively bloodless, increases chance of wound complications
What kind of incision is used for a laparoscopy?
Subumbilical incision
What must care be taken to avoid if a lateral port is needed during a laparoscopy?
Must avoid the inferior epigastric artery
How can view of the organs during a laparoscopy be improved?
Position of uterus can be manipulated by grasping the cervix with forceps inserted through vagina
Where does the inferior epigastric artery emerge?
Just medial to the deep inguinal ring = passes in superomedial direction posterior to rectus abdominis
What occurs in an abdominal hysterectomy?
Removal of uterus via an incision in the abdominal wall
What occurs in a vaginal hysterectomy?
Removal of uterus via vagina
What structures must be differentiated from each other during a hysterectomy?
Ureter and uterine artery
How can the ureter be distinguished from the uterine artery?
Ureter passes inferior to artery
Ureter will often vermiculate when touched
