NEET-PG 2012 Practice Questions

Q: Which of the following local anesthetics has the highest maximum concentration allowed for epidural block?

Chlorprocaine. ***Chlorprocaine*** - **Chlorprocaine** is an ester-type local anesthetic that can be safely used in higher concentrations for epidural blocks up to **3%**, due to its rapid hydrolysis by plasma pseudocholinesterase, leading to a very short half-life and reduced systemic toxicity. - Its rapid metabolism minimizes the risk of accumulation and systemic toxicity, making it a suitable choice when a dense block is needed and a short duration of action is acceptable. *Lidocaine* - **Lidocaine** is an amide-type local anesthetic commonly used in epidural blocks, but its maximum concentration for this application is typically limited to **2%** to avoid systemic toxicity. - Higher concentrations of lidocaine are associated with an increased risk of neurological and cardiovascular adverse effects. *Ropivacaine* - **Ropivacaine** is an amide-type local anesthetic that is less cardiotoxic than bupivacaine, with common concentrations for epidural use ranging from **0.2% to 1%**. - Its maximum concentration is significantly lower than chlorprocaine due to its longer duration of action and potential for systemic toxicity at higher doses. *Bupivacaine* - **Bupivacaine** is a potent amide-type local anesthetic with a high risk of cardiotoxicity, and its maximum concentration for epidural use is generally restricted to **0.5%** or even less for continuous infusions. - Using concentrations above this limit significantly increases the risk of severe cardiovascular complications, including arrhythmias and cardiac arrest.

Q: An incised-looking laceration is seen in all except:

Chest. ***Chest*** - The skin and subcutaneous tissue over the chest are generally **pliable and abundant**, allowing tissues to stretch and tear irregularly rather than creating a clean, incised-looking wound. - Due to the **underlying musculature and lack of prominent bony structures** just beneath the skin, impacts tend to cause contusions, irregular lacerations, or deeper tissue damage rather than sharp, distinct cuts. *Shin* - The shin has minimal subcutaneous tissue and skin that is **tightly bound over the tibia**, a prominent bony structure. - Impacts here often cause the skin to be compressed against the bone, leading to a **clean, sharp tear that mimics an incised wound**. *Zygomatic bone* - The skin over the zygomatic bone (cheekbone) is **thin and adheres closely to the underlying bone**. - Trauma to this area can result in a **linear, incised-appearing laceration** due to the skin being split against the rigid bony surface. *Iliac crest* - Similar to the shin and zygomatic bone, the iliac crest is a **superficial bony prominence with thin skin and limited subcutaneous tissue**. - A blunt force impact can cause the skin to **split cleanly over the bone**, creating an incised-looking laceration.

Q: Foamy liver is seen in:

Putrefaction. ***Putrefaction*** - **Foamy liver** is a characteristic post-mortem finding in **putrefaction**, the process of post-mortem decomposition of body tissues. - **Gas-forming bacteria** (especially Clostridium species) produce gases like **hydrogen sulfide, methane, and carbon dioxide** that accumulate within the liver parenchyma. - This creates multiple **gas bubbles** throughout the liver tissue, giving it a characteristic **frothy or foamy appearance** on sectioning. - This is part of the broader putrefactive changes that include gas accumulation in blood vessels (marbling), body cavities, and soft tissues. *Arsenic poisoning* - Acute arsenic poisoning causes **fatty degeneration of the liver**, congestion, and characteristic gastrointestinal findings. - Post-mortem findings include **"rice water" stools**, gastroenteritis, and hepatic congestion, but NOT the foamy liver appearance. - The liver may show fatty changes and cellular necrosis, but gas bubble formation is not a characteristic feature. *Electrocution* - **Electrocution** causes death primarily through cardiac arrest or respiratory paralysis. - Post-mortem findings include **thermal burns** at entry and exit points, Joule burns, and sometimes arborescent markings. - It does not cause foamy liver; tissue changes are related to current passage and thermal effects. *Hanging* - **Hanging** results in **asphyxial death** with characteristic findings of mechanical asphyxia. - Typical findings include **ligature mark**, petechial hemorrhages, facial congestion, and cyanosis. - Does not cause foamy liver, as gas production within hepatic tissue is not a consequence of mechanical asphyxia.

Q: Cause of death for drowning in cold water:

Inability to breathe (asphyxia). ***Inability to breathe (asphyxia)*** - Drowning fundamentally involves **inhalation of water** into the airway, which prevents gas exchange in the lungs, leading to **asphyxia**. - In cold water, the initial gasp reflex can lead to rapid aspiration of water, causing immediate **laryngospasm** and closure of the airway, resulting in inability to breathe. - Asphyxia remains the **most common mechanism** across all types of drowning, including cold water cases. *Loss of consciousness due to hypoxia* - While **hypoxia** certainly occurs in drowning due to lack of gas exchange, loss of consciousness is a *consequence* of prolonged asphyxia, not the primary cause of death. - The immediate cause of death is the inability to oxygenate the blood due to water filling the lungs or severe laryngospasm. *Cardiac arrest due to vagal inhibition* - **Vagal inhibition** (also called **hydrocution** or **immersion syndrome**) is an important mechanism specifically in **cold water drowning**. - Sudden immersion in cold water can trigger massive vagal stimulation leading to immediate cardiac arrest (often asystole) before significant water aspiration occurs. - However, this mechanism occurs in a **minority of cold water drowning cases**, while asphyxia remains the predominant cause of death overall. *Cardiac arrest due to ventricular fibrillation* - **Ventricular fibrillation** can be a terminal event in drowning, often secondary to severe hypoxia and hypothermia, but it is usually not the initial or primary cause of death. - The cessation of breathing and subsequent lack of oxygen directly lead to organ failure, including cardiac dysrhythmias, rather than ventricular fibrillation being the independent initial event.

Q: Burking includes:

Chest compression and airway obstruction. ***Chest compression and airway obstruction*** - Burking is a **homicidal method** of suffocation that involves **covering the mouth and nose** (airway obstruction) combined with **compressing the chest or abdomen** to prevent breathing. - Named after **William Burke**, this technique was used to kill victims without leaving obvious signs of violence, making deaths appear natural. *Ligature strangulation* - Involves using a **cord, rope, or similar object** around the neck to compress blood vessels and/or airway. - Leaves characteristic **ligature marks** on the neck, which burking aims to avoid by using manual compression instead. *Drowning mechanism* - Involves **submersion in liquid** causing respiratory impairment and asphyxia. - Completely different mechanism from burking, which involves **manual suffocation** on dry land without water involvement. *Hanging technique* - Hanging involves **suspension of the body by the neck**, causing death through compression of neck structures. - This is completely different from burking and leaves distinct **hanging marks** on the neck, which burking specifically avoids.

Q: Ehrlichia chaffeensis is the causative agent of -

HME. ***HME (Human Monocytic Ehrlichiosis)*** - **Ehrlichia chaffeensis** is the primary causative agent of **Human Monocytic Ehrlichiosis**, a tick-borne illness. - This bacterium primarily infects **monocytes** and macrophages, leading to characteristic intracellular inclusions called **morulae**. *Glandular fever* - Glandular fever, also known as **infectious mononucleosis**, is predominantly caused by the **Epstein-Barr virus (EBV)**. - It is characterized by fever, sore throat, lymphadenopathy, and fatigue, and is not caused by bacteria. *HGE (Human Granulocytic Ehrlichiosis)* - **Human Granulocytic Ehrlichiosis (HGE)** is caused by **Anaplasma phagocytophilum**, not *Ehrlichia chaffeensis*. - HGE primarily targets **neutrophils** (granulocytes), differentiating it from HME which targets monocytes. *None of the options* - This option is incorrect because *Ehrlichia chaffeensis* is indeed the causative agent of HME, as described above.

Q: Hanging drop method is used for:

Trichomonas. ***Trichomonas*** - The **hanging drop method** is a highly effective technique for visualizing the characteristic **motility** of *Trichomonas vaginalis*. - This method allows for the observation of living, unstained organisms directly from clinical samples, making it valuable for rapid diagnosis. *Toxoplasma* - **Toxoplasma gondii** is an intracellular parasite best identified through serological tests for **antibodies** or molecular diagnostics like **PCR**. - It does not exhibit characteristic motility in a hanging drop preparation that would aid in its direct identification. *Cryptosporidium* - **Cryptosporidium** species are typically identified by detecting **oocysts** in stool samples, often using **acid-fast staining** or **immunofluorescence assays**. - Their small size and lack of distinctive motility under a hanging drop method make this technique unsuitable for their diagnosis. *Plasmodium* - **Plasmodium** species, the causative agents of malaria, are diagnosed by visualizing **parasites within red blood cells** on **Giemsa-stained blood smears**. - The hanging drop method would not effectively identify these intracellular parasites for malaria diagnosis.

Q: All of the following cause Fournier's gangrene except:

Clostridium. ***Clostridium*** - While *Clostridium* species (especially *C. perfringens*) **CAN be isolated** from Fournier's gangrene cases and contribute to gas formation and tissue necrosis, they are **less commonly identified as primary pathogens** compared to other organisms. - In the context of this question, *Clostridium* is considered the "except" option because it is **relatively less frequently implicated** in Fournier's gangrene compared to the other listed organisms, though it is NOT entirely excluded from the microbiology of this condition. - *Clostridium* species are more classically associated with **gas gangrene (clostridial myonecrosis)** in traumatic wounds and deep muscle tissue. *Bacteroides* - ***Bacteroides fragilis*** and other **anaerobic gram-negative bacilli** are among the **most commonly isolated organisms** in Fournier's gangrene. - They produce enzymes that facilitate tissue destruction and contribute significantly to the **polymicrobial synergistic necrotizing infection**. - Essential component of the typical microbial flora in perianal and genital infections. *Streptococcus* - ***Streptococcus pyogenes*** (Group A Streptococcus) and other streptococcal species are **frequently isolated** from Fournier's gangrene. - They produce toxins and enzymes causing **rapid necrotizing fasciitis** with systemic toxicity. - Major contributor to the aggressive nature and rapid progression of the infection. *Staphylococcus* - ***Staphylococcus aureus*** (including MRSA) is **commonly found** in polymicrobial Fournier's gangrene infections. - Contributes to local tissue destruction through toxin production and enzyme activity. - Often isolated from perianal and genital skin flora, facilitating its involvement in these infections.

Q: Rokitansky protuberances are seen in -

Teratoma. ***Teratoma*** - **Rokitansky protuberance** (mural nodule or dermoid plug) is a raised solid area found within a **mature cystic teratoma**, particularly in the ovary [1]. - It often contains various tissues derived from the three germ layers such as **hair**, **sebaceous glands**, bone, and teeth [3]. *Papillary carcinoma* - Characterized by **papillary projections** formed by tumor cells, often seen in thyroid, kidney, or ovary. - While it can have protuberances, these are **composed of malignant cells** and lack the diverse tissue components of a Rokitansky protuberance. *Epidermoid cyst* - A benign cyst lined by **stratified squamous epithelium** and filled with keratin debris, typically located in the skin or skull. - These cysts do not form internal protuberances with heterogeneous tissue types like those seen in teratomas. *Mucinous carcinoma* - A malignant tumor characterized by the production of **mucin**, often affecting the ovary, colon, or breast [2]. - Lesions are typically filled with mucinous material or present as mucinous masses, and do not contain the specific solid Rokitansky protuberance. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Female Genital Tract, p. 1034. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Female Genital Tract, pp. 1033-1034. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Female Genital Tract Disease, pp. 480-481.

Q: Maximum duration of time is spent in NREM stage:

II. ***II*** - **NREM Stage II** constitutes the largest percentage of total sleep time, typically accounting for about 45-55% of an adult's sleep. - This stage is characterized by the presence of **sleep spindles** and **K-complexes** on an EEG, and it is a relatively stable period of sleep. *I* - **NREM Stage I** is the lightest stage of sleep, representing the transition from wakefulness to sleep. - It is the shortest stage, lasting only a few minutes, and is characterized by slow eye movements and a decrease in muscle tone. *III* - **NREM Stage III** (along with Stage IV in older classifications) is considered **slow-wave sleep** or deep sleep. - While crucial for restorative processes, Stage III does not account for the majority of total sleep time, typically being less than Stage II. *IV* - **NREM Stage IV** is the deepest stage of sleep, now often combined with Stage III as part of **slow-wave sleep**. - It involves the lowest brain wave activity and is difficult to awaken from, but its duration is significantly less than Stage II.

Question 1

Which of the following local anesthetics has the highest maximum concentration allowed for epidural block?

Accepted Answer

Chlorprocaine

Answer

Lidocaine

Answer

Ropivacaine

Answer

Bupivacaine

Question 2

An incised-looking laceration is seen in all except:

Accepted Answer

Chest

Answer

Shin

Answer

Zygomatic bone

Answer

Iliac crest

Question 3

Foamy liver is seen in:

Accepted Answer

Putrefaction

Answer

Arsenic poisoning

Answer

Electrocution

Answer

Hanging

Question 4

Cause of death for drowning in cold water:

Accepted Answer

Inability to breathe (asphyxia)

Answer

Loss of consciousness due to hypoxia

Answer

Cardiac arrest due to vagal inhibition

Answer

Cardiac arrest due to ventricular fibrillation

Question 5

Burking includes:

Accepted Answer

Chest compression and airway obstruction

Answer

Ligature strangulation

Answer

Drowning mechanism

Answer

Hanging technique

Question 6

Ehrlichia chaffeensis is the causative agent of -

Accepted Answer

HME

Answer

Glandular fever

Answer

HGE

Answer

None of the options

Question 7

Hanging drop method is used for:

Accepted Answer

Trichomonas

Answer

Toxoplasma

Answer

Cryptosporidium

Answer

Plasmodium

Question 8

All of the following cause Fournier's gangrene except:

Accepted Answer

Clostridium

Answer

Bacteroides

Answer

Streptococcus

Answer

Staphylococcus

Question 9

Rokitansky protuberances are seen in -

Accepted Answer

Teratoma

Answer

Papillary carcinoma

Answer

Epidermoid cyst

Answer

Mucinous carcinoma

Question 10

Maximum duration of time is spent in NREM stage:

Accepted Answer

II

Answer

I

Answer

III

Answer

IV

NEET-PG 2012

Anesthesiology

Forensic Medicine

Microbiology

Pathology

Physiology