Surgical Infections Practice Questions

Q: Preferred time for prophylactic antibiotic administration for surgery?

At the time of induction of anaesthesia. ***At the time of induction of anaesthesia*** - This timing ensures that a **therapeutic concentration** of the antibiotic is present in the tissues at the time of the initial surgical incision, when the risk of bacterial contamination is highest. - Administering the antibiotic too early or too late can reduce its effectiveness in preventing **surgical site infections (SSIs)**. *1 day before surgery* - Administering antibiotics a day before surgery would lead to the drug being **metabolized and eliminated** from the body before the surgical incision is made, rendering it ineffective for prophylaxis. - This timing also increases the risk of **antibiotic resistance** development without providing adequate protection against SSIs. *I.V. during surgery* - Administering the antibiotic intravenously during surgery means that the drug will not have reached sufficient **tissue concentrations** at the crucial moment of the initial incision. - The protective effect is largely dependent on adequate tissue levels **prior to contamination**, which would not be achieved by administration only during the procedure. *I.M. 6 hrs before surgery* - While closer to the optimal timing than 1 day before, administering intramuscularly 6 hours prior may result in **suboptimal drug levels** at the time of incision, especially for drugs with shorter half-lives. - Intramuscular administration can also have variable absorption rates compared to intravenous, potentially delaying peak tissue concentration and reducing reliability for **prophylactic efficacy**.

Q: Fibreoptic scopes are sterilized by

Glutaraldehyde. ***Glutaraldehyde*** - **Glutaraldehyde** is the most commonly used agent for **high-level disinfection** of heat-sensitive endoscopes and fibreoptic equipment in clinical practice. - It effectively kills bacteria, viruses, fungi, and most spores through **alkylation** of proteins and nucleic acids. - While technically providing high-level disinfection rather than true sterilization, it is the **standard method** for processing flexible endoscopes between procedures. - **Advantages:** Liquid-based, relatively quick (20-45 minutes), compatible with delicate instruments, and does not require special equipment. *Ethylene oxide* - **Ethylene oxide** (EtO) can achieve true sterilization of heat-sensitive instruments and is sometimes used for rigid endoscopes requiring sterility. - However, it is **not practical for routine flexible endoscope processing** due to: lengthy cycle times (12-24 hours including aeration), need for specialized equipment, toxic residue concerns, and cost. - Glutaraldehyde remains preferred for **routine clinical use** of flexible fibreoptic scopes. *Alcohol* - **Alcohol** (ethanol, isopropanol) is an intermediate-level disinfectant effective against many bacteria and viruses. - It is **not sporicidal** and cannot achieve high-level disinfection or sterilization. - Used only for surface disinfection and preliminary cleaning, not as the primary disinfection method for endoscopes. *Autoclaving* - **Autoclaving** uses high-pressure steam (121°C or 134°C) for sterilization and is highly effective. - **Not suitable for flexible fibreoptic scopes** as the high heat would **damage** the delicate optical fibers, lenses, and plastic components. - May be used for some heat-resistant rigid endoscopic instruments.

Q: Acute paronychia is commonly treated by:

Incision and drainage. ***I & D*** - **Incision and drainage (I&D)** is the primary treatment for **acute paronychia** when an abscess has formed. - This procedure relieves pressure, drains pus, and promotes healing of the infection around the nail. *Nail bed destruction* - **Nail bed destruction** is typically performed for chronic or recurrent nail problems, such as **onychomycosis** or **ingrown toenails**, not for acute infections. - It involves removing or chemically destroying the nail matrix to prevent future nail growth. *Partial nail avulsion* - **Partial nail avulsion** involves removing only a portion of the nail, usually for **ingrown toenails** or local trauma, and is not the primary treatment for resolving the pus pocket of acute paronychia. - The focus is on removing the problematic nail edge, not draining an infection. *Total nail avulsion* - **Total nail avulsion** is the complete removal of the nail plate, generally reserved for severe infections, trauma, or certain fungal infections where the entire nail is involved, and it is considered a more aggressive procedure than needed for most uncomplicated acute paronychia. - This procedure leaves the nail bed exposed and can be painful with a longer recovery time.

Q: Which of the following is true regarding prophylactic antibiotic use in surgical practice?

first dose is given before induction of anesthesia. ***First dose is given before induction of anesthesia*** - **Prophylactic antibiotics** are most effective when present in adequate concentrations in tissue **before the surgical incision** is made - Administering the first dose **within 60 minutes before incision** (typically before induction of anesthesia) ensures optimal tissue levels at the time of potential bacterial contamination - This timing is a **key principle** of effective surgical antibiotic prophylaxis *Is given orally* - Surgical prophylaxis requires **intravenous administration** for rapid and reliable tissue levels - IV route ensures predictable bioavailability and adequate drug concentration at the surgical site - Oral route may be used in specific outpatient scenarios but is **not standard** for surgical prophylaxis *Continued for a minimum of 7 days* - Prophylactic antibiotics are given for **short duration**: typically a **single dose** or continued for less than 24 hours post-operatively - Extended courses (≥7 days) are reserved for **treating established infections**, not prophylaxis - Prolonged use increases risk of **antibiotic resistance**, adverse effects, and *Clostridioides difficile* infection *Depends on individual preference* - Prophylactic antibiotic use follows **evidence-based guidelines** and institutional protocols, not individual preference - Guidelines consider surgery type, patient risk factors, local **antibiogram data**, and established efficacy - Standardized protocols improve outcomes and reduce surgical site infections

Q: When do we have to start antibiotics to prevent post-operative infection?

30-60 minutes before incision (up to 24 hours post-op). ***30-60 minutes before incision (up to 24 hours post-op)*** - Surgical antibiotic prophylaxis (SAP) should be administered **30-60 minutes before surgical incision** to ensure adequate tissue and serum concentrations at the time of incision. - This timing allows optimal drug distribution to surgical tissues, which is crucial for preventing surgical site infections (SSIs). - For most clean and clean-contaminated surgeries, prophylaxis should be limited to a **single dose** or continued for **maximum 24 hours post-operatively** as per WHO and CDC guidelines. - Prolonged post-operative antibiotics beyond 24 hours do **not** reduce infection rates and increase the risk of **antibiotic resistance** and **adverse effects**. *1 week before surgery* - Administering antibiotics this far in advance is **unnecessary** and **ineffective** for surgical prophylaxis. - It increases the risk of **antibiotic resistance** and does not guarantee adequate drug levels at the time of incision. - Pre-operative antibiotic use should be avoided unless treating an active infection. *2 days before surgery* - This timeframe is too early to achieve prophylactic benefit during the surgical procedure. - Prolonged pre-operative use promotes **bacterial resistance** without providing additional protection. - Drug levels will not be optimal at the time of incision due to metabolism and excretion. *After surgery* - Starting antibiotics **after surgical incision** is **too late** for prophylaxis as contamination has already occurred. - Post-operative initiation is considered **therapeutic treatment** for established infection, not prevention. - The critical window for prophylaxis is the period from skin incision to wound closure.

Q: Which of the following is a risk factor for postoperative infection after hysterectomy?

Surgery for malignancy. ***Surgery for malignancy*** - **Surgery for malignancy** is a significant risk factor for postoperative infection after hysterectomy due to multiple factors: - **Longer operative duration** and more extensive dissection increase tissue trauma and infection risk - **Radical hysterectomy** for cancer involves wider resection margins and lymph node dissection, creating larger surgical fields - Cancer patients often have **underlying immunocompromise** from the malignancy itself - **Greater blood loss** may necessitate transfusions, which can impact immune function - **Compromised tissue perfusion** in the surgical field due to tumor involvement - Studies consistently show **higher surgical site infection rates** in cancer surgeries compared to benign indications *Urinary catheterization > 7 days* - While prolonged catheterization does increase UTI risk, standard practice involves **catheter removal within 24-48 hours** after uncomplicated hysterectomy - Catheterization beyond 7 days is **uncommon** in routine hysterectomy and would typically indicate complications already present - Though a risk factor when it occurs, it's not the primary established risk factor in standard hysterectomy practice *Use of prophylactic antibiotics* - **Prophylactic antibiotics** are a protective measure that **reduces infection risk** by 50-75% - Standard perioperative protocol specifically designed to prevent surgical site infections - Their use is recommended by all major surgical guidelines (ACOG, WHO, CDC) *Age > 50 yrs* - Age alone is **not an independent risk factor** for postoperative infection - While older patients may have more comorbidities, **age per se** does not significantly increase infection risk - The presence of specific comorbidities (diabetes, immunosuppression) rather than chronological age determines risk

Q: A patient is diagnosed having paronychia. Which of the following would one expect to note during the assessment?

Red shiny skin around the nail fold. ***Red shiny skin around the nail bed*** - **Paronychia** is an infection of the **nail fold**, the skin around the nail. This inflammation results in characteristic redness and swelling. - The skin often appears **shiny** due to underlying inflammation and edema in the perionychial area. *Swelling involving the distal pulp* - Swelling of the **distal pulp** (fingertip pad) is more characteristic of a **felon**, which is a closed-space infection of the fingertip pulp. - While paronychia can be painful, its primary location of swelling is the **nail fold**, not solely the pulp. *Avulsion of nail from its bed* - **Onycholysis** or avulsion (separation) of the nail from its bed can occur in various nail disorders, but it is not a direct or defining feature of acute paronychia. - Nail avulsion is often seen in conditions like **psoriasis**, fungal infections, or trauma. *White taut skin at the finger pulp* - **White and taut skin** surrounding the finger pulp suggests ischemia or necrosis, which is not typical of paronychia. - Such findings might be seen in conditions like **frostbite** or severe vascular compromise.

Q: Percentage of surgical site infection in patients with a clean-contaminated wound after prophylactic antibiotic administration?

<10%. ***<10%*** - For **clean-contaminated wounds**, the rate of surgical site infection (SSI) is generally maintained **below 10%** with proper prophylactic antibiotic administration. - This low percentage reflects the effectiveness of **antibiotic prophylaxis** in preventing SSIs in wounds where controlled entry into a viscus is made. *1-2%* - This range is more typical for **clean wounds** where no viscus is entered, and the risk of contamination is minimal. - Prophylactic antibiotics are highly effective in clean wounds, leading to a very low infection rate. *10-20%* - This percentage is generally considered high for clean-contaminated wounds and may indicate suboptimal antibiotic prophylaxis, an underlying patient risk factor, or a technical surgical issue. - The goal of prophylactic antibiotics is to keep the infection rate well below this range for this wound class. *20-30%* - An infection rate in this range is typically seen in **contaminated** or **dirty wounds**, or in cases where no antibiotics were given. - Such high rates would be unacceptable for a clean-contaminated procedure with appropriate prophylaxis.

Question 1

Preferred time for prophylactic antibiotic administration for surgery?

Accepted Answer

At the time of induction of anaesthesia

Answer

1 day before surgery

Answer

I.V. during surgery

Answer

I.M. 6 hrs before surgery

Question 2

Fibreoptic scopes are sterilized by

Accepted Answer

Glutaraldehyde

Answer

Ethylene oxide

Answer

Alcohol

Answer

Autoclaving

Question 3

Most common cause of death in burns is

Accepted Answer

Septicemic shock

Answer

Hypovolemic shock

Answer

Neurogenic shock

Answer

Haemorrhagic shock

Question 4

Acute paronychia is commonly treated by:

Accepted Answer

Incision and drainage

Answer

Nail bed destruction

Answer

Partial nail avulsion

Answer

Total nail avulsion

Question 5

Which of the following is true regarding prophylactic antibiotic use in surgical practice?

Accepted Answer

first dose is given before induction of anesthesia

Answer

is given orally

Answer

continued for a minimum of 7 days

Answer

depends on individual preference

Question 6

When do we have to start antibiotics to prevent post-operative infection?

Accepted Answer

30-60 minutes before incision (up to 24 hours post-op)

Answer

1 week before surgery

Answer

2 days before surgery

Answer

After surgery

Question 7

Which of the following is a risk factor for postoperative infection after hysterectomy?

Accepted Answer

Surgery for malignancy

Answer

Use of prophylactic antibiotics

Answer

Age > 50 yrs

Answer

Urinary catheterization > 7 days

Question 8

Which of the following is true about tenosynovitis of the finger?

Accepted Answer

Tenosynovitis of little finger will spread to thumb rather than ring finger.

Answer

Treatment is conservative.

Answer

Fingers held in mild extension / Extension deformity at the involved fingers.

Answer

With involvement of little finger the infection can spread to the ring finger.

Question 9

A patient is diagnosed having paronychia. Which of the following would one expect to note during the assessment?

Accepted Answer

Red shiny skin around the nail fold

Answer

Swelling involving the distal pulp

Answer

Avulsion of nail from its bed

Answer

White taut skin at the finger pulp

Question 10

Percentage of surgical site infection in patients with a clean-contaminated wound after prophylactic antibiotic administration?

Accepted Answer

<10%

Answer

1-2%

Answer

10-20%

Answer

20-30%

Surgical Infections — MCQs

Surgical Infections — MCQs

On this page

Practice by Chapter

Want unlimited practice?