This document provides an overview of the abdominal surgery curriculum for appendectomy. It discusses the indications for and differences between laparoscopic versus open appendectomy. The benefits of the laparoscopic approach include shorter hospital stays, faster return to work, fewer wound infections, and better cosmetic results. Considerations for anesthesia include fluid management, issues related to pneumoperitoneum, and special precautions for pregnancy. Sample board review questions are provided to test understanding of concepts like hypotension during insufflation and appropriate interventions.

1. Abdominal Surgery Curriculum
Jen Basarab-Tung
Appendectomy

2. Background
 Indicated for acute or perforated appendicitis
 Diagnosed or suspected
 10-15% false positive rate acceptable
 Laparoscopic vs. open
 Most appendectomies are laparoscopic
 3 trocars (umbilical, suprapubic, LLQ)
 Open appendectomy done through RLQ or right
paramedian incision
 Cochrane review shows small benefit to
laparoscopic procedure, particularly for young,
female, obese, and employed patients

3. Benefits of Lap Approach
 Shorter hospital stay
 Faster return to work
 Fewer wound infections
 Exception: more intra-abdominal
abscesses with laparoscopic
 Decreased pain
 Better cosmetic result

4. Relevant Anatomy
A. Trocar placement B. Internal anatomy

5. Preoperative Considerations
 Most common in teens and young adults,
but can occur at any age
 Patients may have received antibiotics in
the ED or on the floor
 Pathogens are usually enteric gram negatives
 Cefazolin or cefoxitin commonly
used at Stanford
 Hypovolemia is common
 Decreased po intake, vomiting

6. Induction and Maintenance
 Treat any acute abdomen as a full stomach
 RSI or modified RSI and endotracheal
intubation
 Most patients require only standard
monitors and one PIV
 Exception: septic pts from perforated appendix
 Muscle relaxation is helpful when under
pneumoperitoneum
 Twitch monitoring (goal TOF 1 of 4)

7. Fluid Management
 Keep in mind: Foley often not placed due
to brevity of procedure (60-90 minutes)
 Patients often present with vomiting and
decreased po intake and may be septic
 Replace fluid deficit and intraoperative losses
 Fortunately, insensible losses and blood
loss are minimal
 5-8 mL/kg/hr of crystalloid as a
guideline, but let the vitals be your guide
 Resuscitate more if patient is septic or
volume depleted

8. Issues w/ Pneumoperitoneum
 Avoidance of N2O
 Some use N2O for emergence after
discontinuation of pneumoperitoneum, but
check with attending because of PONV
 Difficulties with Ventilation
 Pneumoperitoneum can increase PIPs,
especially in obese patients
 Consider pressure control ventilation
 Cardiovascular changes
 Decreased venous return -> decreased CO
 Compensatory increase in SVR

9. Special Considerations
 PONV is common
 Zofran for virtually everyone; consider additional
prophylaxis with decadron
 Extubate awake to protect airway
 Pregnancy
 Appendectomy is the most common non-OB
procedure performed on pregnant women
 Recent evidence shows laparoscopy is safe in all
stages of pregnancy
 Preop OB consult, left uterine displacement,
aspiration precautions, careful trocar placement
 Fetal monitoring generally preferred during
surgery in late-term pregnant women, but
not feasible as monitors would encroach on
surgical field

10. Board Review Questions
 In using general anesthesia for
laparoscopic appendectomy, which of the
following is true?
 A. Inhaled N2O will diffuse into CO2-containing
spaces and increase their volume or pressure
 B. Peak airway pressures usually do not
change under pneumoperitoneum.
 C. Small but detectable (via Doppler or
TEE) CO2 emboli are the exception rather
than the rule
 D. Minute ventilation will need to be
approximately tripled to eliminate the
exogenously administered CO2

11. Board Review Questions
 Answer: A
 N2O will diffuse into CO2-containing spaces and
increase the pressure and/or volume.
 Pneumoperitoneum usually increases peak
airway pressures.
 CO2 emboli are common during laparoscopic
procedures; however, most are fortunately of
little clinical significance.
 Minute ventilation needs to be increased by
about a third in the average patient during
laparoscopic surgery in order to maintain a
normal value for end-tidal CO2.

12. Board Review Questions
 A 27 year-old woman is anesthetized with
propofol, sevoflurane, N2O, and O2 for
laparoscopic appendectomy. She is placed in
Trendelenburg position after insertion of the
needle through the abdominal wall, and CO2 is
insufflated. There is sudden onset of
hypotension. The hypotension may be due to
any of the following EXCEPT:
 A. CO2 embolism
 B. Hemorrhage
 C. Compression of the IVC
 D. Position

13. Board Review Questions
 Answer: D
 The patient for laparoscopic appendectomy
may be hypotensive due to CO2 embolus,
hemorrhage, and compression of the IVC
from increased intra-abdominal pressure.
The Trendelenburg position should not cause
hypotension.

14. Board Review Questions
 In the previous scenario, which of the
following is NOT an appropriate step to
take?
 A. Administer IV fluids
 B. Inform the surgeon
 C. Administer epinephrine
 D. Discontinue the N2O

15. Board Review Questions
 Answer: C
 After the onset of hypotension during laparoscopic surgery, the
surgeon should immediately be informed and the insufflation of CO2
discontinued.
 In the case of CO2 embolism, hypotension and desaturation are the
usual presenting signs. Administration of 100% O2 may increase
oxygen saturation.
 Placement of the patient in the left lateral position acts to trap the
gas in the right ventricle and decrease the amount entering the
pulmonary artery. Since CO2 is very soluble, aspiration of the gas
via a right atrial catheter is rarely necessary.
 The occurrence of hemorrhage via laceration or cannulation of a
blood vessel with the insufflating needle may require laparotomy for
repair.
 If the hypotension is due to IVC compression, decreasing the intra-
abdominal pressure should increase the blood pressure. Epinephrine
is not indicated unless the hypotension persists and requires
beginning ACLS.

16. References
 Curet MJ et al. (2009). Laparoscopic General Surgery.
In Jaffe RA, Samuels SI (Eds.), Anesthesiologist’s
Manual of Surgical Procedures (4th Ed., pp. 569-608).
Philadelphia: Lippincott Williams and Wilkins.
 Jeong J et al. Laparoscopic appendectomy is a safe
and beneficial procedure in pregnant women. Surg
Laparosc Endosc Percutan Tech 2011;21:1, 24-27.
 Sauerland S, Jaschinski T, Neugebauer EA.
Laparoscopic versus open surgery for suspected
appendicitis. Cochrane Database Syst Rev. 2010 Oct
6;(10):CD001546.
 Dershwitz M, ed. The MGH Board Review of
Anesthesiology, 5th ed. New York: Appelton & Lange,
1999.