COMAT General Surgery Final Exam Prep (2026-
2027) Comprehensive Study Guide with 100
Practice Questions & Detailed Rationales
QUESTIONS AND ANSWERS ALREADY GRADED A+
Table of Contents
• Section 1: Perioperative Care & Complications (Questions 1-12)
• Section 2: Surgical Emergencies (Acute Abdomen) (Questions 13-20)
• Section 3: Gastrointestinal Surgery (Questions 21-35)
• Section 4: Hepatobiliary Surgery (Questions 36-42)
• Section 5: Breast & Endocrine Surgery (Questions 43-50)
• Section 6: Trauma & Burns (Questions 51-58)
• Section 7: Vascular Surgery (Questions 59-64)
• Section 8: Urology (Questions 65-70)
• Section 9: Skin, Soft Tissue & Wound Healing (Questions 71-76)
• Section 10: Surgical Oncology (Questions 77-85)
• Section 11: Fluid & Electrolyte Management (Questions 86-90)
• Section 12: Osteopathic Principles in Surgery (Questions 91-95)
• Section 13: High-Yield Mixed Review (Questions 96-100)
Section 1: Perioperative Care & Complications (Questions 1-12)
Q1. A 65-year-old male undergoes elective right hemicolectomy for colon cancer. On
postoperative day 3, he develops fever (38.9°C), tachycardia, and tachypnea. His oxygen
saturation is 88% on room air. On examination, he is confused and has crackles in the right lung
base. What is the most likely diagnosis?
A) Atelectasis
B) Pulmonary embolism
,C) Hospital-acquired pneumonia
D) Aspiration pneumonia
Answer: C – Hospital-acquired pneumonia
Rationale: This patient presents with fever, hypoxia, crackles, and altered mental status on
postoperative day 3, which is consistent with hospital-acquired pneumonia. The timing (day 3)
helps distinguish it from atelectasis (which typically occurs earlier, often within 24 hours, and
presents with low-grade fever and crackles that improve with deep breathing). While pulmonary
embolism is a consideration, the presence of crackles and fever makes pneumonia more likely .
Q2. A 45-year-old woman undergoes laparoscopic cholecystectomy. On postoperative day 2, she
develops fever (38.5°C), dysuria, and urinary frequency. She has an indwelling urinary catheter
that was placed during surgery and remains in place. Urinalysis shows leukocyte esterase and
nitrites. What is the most appropriate next step?
A) Remove the urinary catheter and obtain a urine culture
B) Start empiric antibiotics without removing the catheter
C) Obtain a CT scan of the abdomen and pelvis
D) Perform a bladder scan to assess for urinary retention
Answer: A – Remove the urinary catheter and obtain a urine culture
Rationale: This patient has a catheter-associated urinary tract infection (CAUTI). The first step in
management is removal of the indwelling catheter, which eliminates the source of bacterial
contamination. After catheter removal, a urine culture should be obtained to guide antibiotic
therapy. The most common organisms associated with CAUTI are enteric organisms including E.
coli, Klebsiella, and Proteus mirabilis .
Q3. A 70-year-old male undergoes emergent exploratory laparotomy for a perforated duodenal
ulcer. On postoperative day 5, he develops fever (39°C), abdominal pain, and purulent drainage
from the surgical incision. The wound edges are erythematous and tender. What is the most
appropriate next step?
A) Obtain wound cultures and start empiric antibiotics
B) Open the wound, irrigate, and debride necrotic tissue
C) Apply a sterile dressing and observe for 24 hours
D) Obtain a CT scan of the abdomen
Answer: B – Open the wound, irrigate, and debride necrotic tissue
,Rationale: This patient presents with a surgical site infection (wound infection) on postoperative
day 5, which is the classic timing for wound infections. The appropriate management is to open
the wound to allow drainage, irrigate the wound, and debride any necrotic tissue. Once the
wound is opened, it can be left to heal by secondary intention or packed. Wound cultures may
be obtained, but opening the wound is the priority. The "5 W's" of postoperative fever help
localize the source of fever: Wind (pneumonia/PE), Water (UTI), Wound (surgical site infection),
Walk (DVT), and Wonder Drugs (drug fever) .
Q4. A 55-year-old female undergoes total hip arthroplasty. On postoperative day 6, she
develops acute onset of shortness of breath, pleuritic chest pain, and hemoptysis. Her oxygen
saturation is 85% on room air. What is the most appropriate initial diagnostic test?
A) D-dimer
B) CT pulmonary angiography
C) Chest X-ray
D) Ventilation-perfusion scan
Answer: B – CT pulmonary angiography
Rationale: This patient presents with signs and symptoms concerning for pulmonary embolism
(PE) on postoperative day 6. The most appropriate initial diagnostic test in a patient with high
clinical suspicion for PE is CT pulmonary angiography (CTPA), which has high sensitivity and
specificity for detecting PE. While D-dimer is useful for ruling out PE in low-risk patients, it is less
specific in hospitalized post-surgical patients who often have elevated D-dimer from other
causes. Deep vein thrombosis (DVT) is a risk in post-surgical patients and is one of the "5 W's" of
postoperative fever ("Walk") .
Q5. A 60-year-old male develops a fever on postoperative day 9 after a Whipple procedure. He
is on broad-spectrum antibiotics including vancomycin and piperacillin-tazobactam. Examination
is unremarkable except for a diffuse maculopapular rash. No source of infection is identified on
workup. What is the most likely diagnosis?
A) Surgical site infection
B) Drug fever
C) Central line-associated bloodstream infection
D) Clostridioides difficile colitis
Answer: B – Drug fever
, Rationale: Drug fever is a diagnosis of exclusion that should be considered when a
postoperative patient develops fever without an identifiable infectious source, especially when
receiving medications known to cause drug fever. Drug fever is typically associated with
anticonvulsants, beta-lactam antibiotics, sulfonamides, and allopurinol. It usually occurs within
1-2 weeks of drug initiation. The presence of a diffuse rash is a clue, though drug fever can
occur without rash. Discontinuation of the offending agent typically leads to resolution of fever
within 24-72 hours. This is one of the "5 W's" ("Wonder Drugs") .
Q6. A 40-year-old male undergoes splenectomy for traumatic spleen rupture. On postoperative
day 1, his platelet count is 450,000/μL (normal: 150,000-400,000). What is the most appropriate
management?
A) Start aspirin 81 mg daily
B) Start low-molecular-weight heparin
C) Observe with no intervention
D) Start warfarin
Answer: C – Observe with no intervention
Rationale: Reactive thrombocytosis (platelet count >400,000/μL) is common following
splenectomy and typically peaks at 1-3 weeks post-surgery. This reactive process is generally
benign and does not require pharmacologic intervention unless the platelet count exceeds
1,000,000/μL or there are additional risk factors for thrombosis. Aspirin may be considered for
very high counts (>1,000,000/μL) or in patients with additional thrombotic risk factors. Routine
anticoagulation is not indicated for mild reactive thrombocytosis .
Q7. A 75-year-old male undergoes emergent repair of a strangulated inguinal hernia. On
postoperative day 2, he develops fever, tachycardia, and hypotension. Physical examination
reveals a tender, erythematous right lower extremity with edema extending from the calf to the
thigh. What is the most appropriate next step?
A) Obtain a venous duplex ultrasound
B) Start empiric antibiotics
C) Obtain a D-dimer
D) Apply warm compresses to the extremity
Answer: A – Obtain a venous duplex ultrasound
2027) Comprehensive Study Guide with 100
Practice Questions & Detailed Rationales
QUESTIONS AND ANSWERS ALREADY GRADED A+
Table of Contents
• Section 1: Perioperative Care & Complications (Questions 1-12)
• Section 2: Surgical Emergencies (Acute Abdomen) (Questions 13-20)
• Section 3: Gastrointestinal Surgery (Questions 21-35)
• Section 4: Hepatobiliary Surgery (Questions 36-42)
• Section 5: Breast & Endocrine Surgery (Questions 43-50)
• Section 6: Trauma & Burns (Questions 51-58)
• Section 7: Vascular Surgery (Questions 59-64)
• Section 8: Urology (Questions 65-70)
• Section 9: Skin, Soft Tissue & Wound Healing (Questions 71-76)
• Section 10: Surgical Oncology (Questions 77-85)
• Section 11: Fluid & Electrolyte Management (Questions 86-90)
• Section 12: Osteopathic Principles in Surgery (Questions 91-95)
• Section 13: High-Yield Mixed Review (Questions 96-100)
Section 1: Perioperative Care & Complications (Questions 1-12)
Q1. A 65-year-old male undergoes elective right hemicolectomy for colon cancer. On
postoperative day 3, he develops fever (38.9°C), tachycardia, and tachypnea. His oxygen
saturation is 88% on room air. On examination, he is confused and has crackles in the right lung
base. What is the most likely diagnosis?
A) Atelectasis
B) Pulmonary embolism
,C) Hospital-acquired pneumonia
D) Aspiration pneumonia
Answer: C – Hospital-acquired pneumonia
Rationale: This patient presents with fever, hypoxia, crackles, and altered mental status on
postoperative day 3, which is consistent with hospital-acquired pneumonia. The timing (day 3)
helps distinguish it from atelectasis (which typically occurs earlier, often within 24 hours, and
presents with low-grade fever and crackles that improve with deep breathing). While pulmonary
embolism is a consideration, the presence of crackles and fever makes pneumonia more likely .
Q2. A 45-year-old woman undergoes laparoscopic cholecystectomy. On postoperative day 2, she
develops fever (38.5°C), dysuria, and urinary frequency. She has an indwelling urinary catheter
that was placed during surgery and remains in place. Urinalysis shows leukocyte esterase and
nitrites. What is the most appropriate next step?
A) Remove the urinary catheter and obtain a urine culture
B) Start empiric antibiotics without removing the catheter
C) Obtain a CT scan of the abdomen and pelvis
D) Perform a bladder scan to assess for urinary retention
Answer: A – Remove the urinary catheter and obtain a urine culture
Rationale: This patient has a catheter-associated urinary tract infection (CAUTI). The first step in
management is removal of the indwelling catheter, which eliminates the source of bacterial
contamination. After catheter removal, a urine culture should be obtained to guide antibiotic
therapy. The most common organisms associated with CAUTI are enteric organisms including E.
coli, Klebsiella, and Proteus mirabilis .
Q3. A 70-year-old male undergoes emergent exploratory laparotomy for a perforated duodenal
ulcer. On postoperative day 5, he develops fever (39°C), abdominal pain, and purulent drainage
from the surgical incision. The wound edges are erythematous and tender. What is the most
appropriate next step?
A) Obtain wound cultures and start empiric antibiotics
B) Open the wound, irrigate, and debride necrotic tissue
C) Apply a sterile dressing and observe for 24 hours
D) Obtain a CT scan of the abdomen
Answer: B – Open the wound, irrigate, and debride necrotic tissue
,Rationale: This patient presents with a surgical site infection (wound infection) on postoperative
day 5, which is the classic timing for wound infections. The appropriate management is to open
the wound to allow drainage, irrigate the wound, and debride any necrotic tissue. Once the
wound is opened, it can be left to heal by secondary intention or packed. Wound cultures may
be obtained, but opening the wound is the priority. The "5 W's" of postoperative fever help
localize the source of fever: Wind (pneumonia/PE), Water (UTI), Wound (surgical site infection),
Walk (DVT), and Wonder Drugs (drug fever) .
Q4. A 55-year-old female undergoes total hip arthroplasty. On postoperative day 6, she
develops acute onset of shortness of breath, pleuritic chest pain, and hemoptysis. Her oxygen
saturation is 85% on room air. What is the most appropriate initial diagnostic test?
A) D-dimer
B) CT pulmonary angiography
C) Chest X-ray
D) Ventilation-perfusion scan
Answer: B – CT pulmonary angiography
Rationale: This patient presents with signs and symptoms concerning for pulmonary embolism
(PE) on postoperative day 6. The most appropriate initial diagnostic test in a patient with high
clinical suspicion for PE is CT pulmonary angiography (CTPA), which has high sensitivity and
specificity for detecting PE. While D-dimer is useful for ruling out PE in low-risk patients, it is less
specific in hospitalized post-surgical patients who often have elevated D-dimer from other
causes. Deep vein thrombosis (DVT) is a risk in post-surgical patients and is one of the "5 W's" of
postoperative fever ("Walk") .
Q5. A 60-year-old male develops a fever on postoperative day 9 after a Whipple procedure. He
is on broad-spectrum antibiotics including vancomycin and piperacillin-tazobactam. Examination
is unremarkable except for a diffuse maculopapular rash. No source of infection is identified on
workup. What is the most likely diagnosis?
A) Surgical site infection
B) Drug fever
C) Central line-associated bloodstream infection
D) Clostridioides difficile colitis
Answer: B – Drug fever
, Rationale: Drug fever is a diagnosis of exclusion that should be considered when a
postoperative patient develops fever without an identifiable infectious source, especially when
receiving medications known to cause drug fever. Drug fever is typically associated with
anticonvulsants, beta-lactam antibiotics, sulfonamides, and allopurinol. It usually occurs within
1-2 weeks of drug initiation. The presence of a diffuse rash is a clue, though drug fever can
occur without rash. Discontinuation of the offending agent typically leads to resolution of fever
within 24-72 hours. This is one of the "5 W's" ("Wonder Drugs") .
Q6. A 40-year-old male undergoes splenectomy for traumatic spleen rupture. On postoperative
day 1, his platelet count is 450,000/μL (normal: 150,000-400,000). What is the most appropriate
management?
A) Start aspirin 81 mg daily
B) Start low-molecular-weight heparin
C) Observe with no intervention
D) Start warfarin
Answer: C – Observe with no intervention
Rationale: Reactive thrombocytosis (platelet count >400,000/μL) is common following
splenectomy and typically peaks at 1-3 weeks post-surgery. This reactive process is generally
benign and does not require pharmacologic intervention unless the platelet count exceeds
1,000,000/μL or there are additional risk factors for thrombosis. Aspirin may be considered for
very high counts (>1,000,000/μL) or in patients with additional thrombotic risk factors. Routine
anticoagulation is not indicated for mild reactive thrombocytosis .
Q7. A 75-year-old male undergoes emergent repair of a strangulated inguinal hernia. On
postoperative day 2, he develops fever, tachycardia, and hypotension. Physical examination
reveals a tender, erythematous right lower extremity with edema extending from the calf to the
thigh. What is the most appropriate next step?
A) Obtain a venous duplex ultrasound
B) Start empiric antibiotics
C) Obtain a D-dimer
D) Apply warm compresses to the extremity
Answer: A – Obtain a venous duplex ultrasound
