Surgery

1344 questions

Question 781Question →

Match each post-bariatric surgery clinical presentation with the most likely diagnosis or surgical complication.

Click a left item, then click its matching right item

Items

A 38-year-old female, 3 years status-post Roux-en-Y gastric bypass, presents with abrupt-onset, severe, colicky periumbilical pain and non-bilious emesis. CT abdomen demonstrates a mesenteric 'swirl' sign.
A 45-year-old male, 12 days status-post laparoscopic sleeve gastrectomy, presents with unexplained tachycardia of 125/min, fever of 38.6°C (101.5°F), and new-onset left upper quadrant pain radiating to the left shoulder.
A 42-year-old female, 8 months status-post Roux-en-Y gastric bypass, presents with chronic burning epigastric pain, nausea, and recent onset of melena. She regularly uses naproxen for osteoarthritis.
A 35-year-old female, 4 months status-post Roux-en-Y gastric bypass, reports lightheadedness, flushing, diaphoresis, and crampy abdominal pain occurring 15-30 minutes after consuming high-carbohydrate meals.

Matches

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Answer

Internal hernia matches with colicky pain and CT swirl sign. Gastric staple-line leak matches with early post-operative tachycardia and fever. Marginal ulceration matches with NSAID use and melena. Early dumping syndrome matches with postprandial vasomotor symptoms.
Each bariatric complication has a distinct presentation: internal hernias present with small bowel obstruction and mesenteric twisting (swirl sign); leaks present early with sepsis and tachycardia; marginal ulcers are exacerbated by NSAID use and present with pain and bleeding; and dumping syndrome presents with vasomotor instability after high-carbohydrate meals.

Step-by-Step Solution

1
Analyze the timeframe of the complication relative to the bariatric surgery date.
Early presentations (1-2 weeks) strongly suggest acute surgical complications like staple-line leaks. Late presentations (months to years) suggest structural, mucosal, or physiologic changes like internal hernias, marginal ulcers, or dumping syndrome.
Post-operative bariatric complications follow highly specific temporal patterns that narrow the differential diagnosis.
2
Identify the key pathognomonic clinical sign or symptom in each vignette.
Unexplained tachycardia with sepsis points to a leak. A 'swirl' sign points to an internal hernia. Chronic NSAID use with GI bleeding points to an ulcer. Vasomotor symptoms directly triggered by eating high-carbohydrate meals point to dumping syndrome.
These distinct signs directly correspond to the underlying pathophysiology of each complication.

Key Concept

Recognition and differentiation of specific complications following bariatric surgery, focusing on their timelines, unique clinical manifestations, and risk factors.
Question 782Question →

A 45-year-old man is brought to the emergency department 30 minutes after falling from a 3-story building. He is confused and moaning in pain. His temperature is 36.2°C (97.2°F), blood pressure is 75/40 mm Hg, heart rate is 135/min, and respiratory rate is 24/min. The airway is patent, and breath sounds are clear and equal bilaterally. A portable chest radiograph is unremarkable. A portable pelvic radiograph demonstrates a 4.5-cm diastasis of the pubic symphysis. A pelvic binder is immediately applied and secured appropriately. Focused assessment with sonography for trauma (FAST) demonstrates a large volume of anechoic fluid in the hepatorenal and splenorenal recesses. The patient receives 2 units of uncrossmatched packed red blood cells and 2 units of fresh frozen plasma via a rapid infusion device. Following the transfusion, his blood pressure is 78/42 mm Hg and heart rate is 130/min. Which of the following is the most appropriate next step in management?

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Answer: Immediate exploratory laparotomy

Answer

Immediate exploratory laparotomy
The most appropriate next step in management is immediate exploratory laparotomy. This patient is in severe hemorrhagic shock due to blunt trauma and is a non-responder to initial damage-control resuscitation (pelvic binder application and massive transfusion protocol initiation). The unequivocally positive FAST scan indicates significant intra-abdominal hemorrhage. According to Advanced Trauma Life Support (ATLS) guidelines, a hemodynamically unstable patient with a positive FAST requires an emergent exploratory laparotomy to surgically control the bleeding. Although the patient has a concurrent life-threatening 'open-book' pelvic fracture, the intra-abdominal bleeding takes immediate surgical priority. During the laparotomy, if the patient remains hemodynamically unstable from suspected retroperitoneal pelvic bleeding, concurrent preperitoneal pelvic packing can be performed in the operating room.

Step-by-Step Solution

1
Identify the patient's hemodynamic status.
The patient is in Class III/IV hemorrhagic shock (BP 75/40 mm Hg, HR 135/min) and is a non-responder to initial damage-control resuscitation (binder and blood products).
Establishing hemodynamic instability dictates the urgency and type of subsequent interventions.
2
Assess the sources of hemorrhage.
There are two major sources identified: severe pelvic fracture (diastasis of the pubic symphysis) and intra-abdominal injury (positive FAST).
Multiple sources of hemorrhage require prioritization based on ATLS guidelines.
3
Determine the priority of intervention.
Immediate exploratory laparotomy is chosen as the next step.
In the presence of a positive FAST and hemodynamic instability, intra-abdominal hemorrhage control takes absolute precedence over isolated pelvic interventions.

Key Concept

In hemodynamically unstable blunt trauma patients with multiple sources of hemorrhage (e.g., severe pelvic fracture and positive FAST), exploratory laparotomy is the mandatory next step to control intra-abdominal bleeding.
Estimated Time:1m 30s
Question 783Question →

A 68-year-old woman is recovering in the surgical intensive care unit shortly after undergoing a pancreaticoduodenectomy. Due to poor peripheral venous access, the surgical resident places a right internal jugular central venous catheter. Ten minutes after the procedure, the patient suddenly develops severe shortness of breath. Her temperature is 37.1°C, blood pressure is 76/40 mm Hg, heart rate is 138/min, and respiratory rate is 32/min. Oxygen saturation is 82% on room air. Physical examination reveals distended neck veins, absent breath sounds over the right lung field, and deviation of the trachea to the left side. Arrange the following management steps in the most appropriate chronological sequence for this patient.

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Answer

The correct sequence for managing an acute tension pneumothorax is to first maximize oxygenation, followed immediately by needle decompression, then placement of a definitive chest tube, and finally confirming placement with a chest radiograph.
This patient has developed an iatrogenic tension pneumothorax, a known complication of central venous catheter placement, characterized by obstructive shock, absent unilateral breath sounds, and tracheal deviation. Management must proceed sequentially: initial ABCs with supplemental oxygen, immediate clinical intervention via needle decompression to relieve intrathoracic pressure, definitive surgical intervention via tube thoracostomy, and finally, diagnostic confirmation of the intervention via chest radiography.

Step-by-Step Solution

1
Administer supplemental oxygen.
Maximizes oxygen delivery.
Hypoxia must be immediately addressed as part of primary ABC assessment.
2
Perform needle decompression.
Converts a tension pneumothorax into a simple pneumothorax.
Rapidly relieves the intrathoracic pressure causing obstructive shock and cardiovascular collapse.
3
Insert a chest tube.
Provides continuous air evacuation.
Needle decompression is temporary; a chest tube definitively manages the pleural space.
4
Obtain a chest radiograph.
Visualizes the lung and tube.
Confirms adequate lung re-expansion and proper placement of the thoracostomy tube.

Key Concept

The diagnosis of iatrogenic tension pneumothorax is clinical and requires immediate needle decompression followed by tube thoracostomy before any radiographic confirmation in a hemodynamically unstable patient.
Question 784Question →

Match each postoperative clinical presentation following abdominal surgery to the most likely diagnosis.

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Items

Sudden, copious drainage of serosanguineous fluid from a midline laparotomy incision on postoperative day 7, with intact skin sutures.
Nausea, obstipation, and abdominal distention on postoperative day 3, with X-ray revealing uniformly dilated small and large intestine without a transition point.
Colicky abdominal pain, recurrent vomiting, and hyperactive bowel sounds 3 weeks after surgery, with CT showing a discrete bowel transition point.
Spiking fevers, leukocytosis, and a boggy, tender mass on digital rectal examination on postoperative day 6 following surgery for a perforated viscus.

Matches

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Answer

Presentation 1 matches Fascial dehiscence; Presentation 2 matches Postoperative ileus; Presentation 3 matches Adhesive small bowel obstruction; Presentation 4 matches Pelvic abscess.
Postoperative complications follow distinct clinical patterns. Fascial dehiscence is heralded by sudden serosanguineous drainage. Ileus is a temporary functional motility loss globally affecting the bowel. Mechanical obstruction features localized blockage with hyperactive upstream motility. Pelvic abscesses present with infectious symptoms and dependent fluid collections.

Step-by-Step Solution

1
Analyze the timing and nature of the surgical complication for the first presentation.
Serosanguineous drainage on postoperative day 7 indicates fascial breakdown.
Recognizing classic signs like 'salmon-colored fluid' is key for identifying fascial dehiscence before gross evisceration occurs.
2
Evaluate the imaging findings for the second presentation.
Global bowel dilation without a transition point points to a functional, non-mechanical issue.
Differentiating functional ileus from mechanical obstruction relies heavily on the presence or absence of a discrete transition point.
3
Correlate the physical exam and imaging for the third presentation.
Hyperactive bowel sounds and a discrete transition point confirm a mechanical blockage.
Mechanical obstruction forces the bowel to hyperperistalse against a fixed point, causing colicky pain and high-pitched sounds.
4
Identify the source of infection in the fourth presentation.
Postoperative fever with a boggy rectal mass indicates a dependent fluid collection in the pelvis.
Infected intra-abdominal fluid tends to pool in gravity-dependent areas, such as the rectovesical pouch, palpable on rectal exam.

Key Concept

Diagnosis of postoperative abdominal surgical complications based on timeline, physical exam, and imaging.
Estimated Time:1m 30s
Question 785Question →

A 42-year-old woman presents to the emergency department with steady, severe right upper quadrant abdominal pain that radiates to her right scapula. The pain began 6 hours ago after eating a large, fatty meal. She reports nausea and two episodes of vomiting. Her temperature is 38.2°C (100.8°F), blood pressure is 130/80 mmHg, and heart rate is 92/min. Physical examination reveals tenderness to palpation in the right upper quadrant with inspiratory arrest (positive Murphy sign). Arrange the following steps in the most appropriate chronological sequence for the evaluation and management of this patient.

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Answer

The correct chronological sequence for managing this patient is: initial stabilization (NPO, IV fluids, analgesia), followed by confirmatory diagnostic imaging (RUQ ultrasound), then administration of intravenous antibiotics, and finally definitive surgical treatment (laparoscopic cholecystectomy).
The correct sequence prioritizes patient safety and standard evidence-based stepwise surgical management. Initial stabilization with intravenous fluids, NPO status, and pain control must occur first. Once the patient is stabilized, right upper quadrant ultrasound is the initial diagnostic test of choice. Following confirmation of acute cholecystitis, intravenous antibiotics are initiated to treat and prevent systemic infection. Finally, early laparoscopic cholecystectomy is performed as the definitive, curative intervention.

Step-by-Step Solution

1
Initial stabilization
Patient is made NPO and receives IV fluids and analgesia.
Ensures hemodynamic stability, relieves acute pain, and prepares the gastrointestinal tract for potential surgery.
2
Diagnostic imaging
A right upper quadrant ultrasound is performed.
Ultrasound is the most sensitive and specific initial test for gallstones and signs of gallbladder inflammation (e.g., gallbladder wall thickening, pericholecystic fluid).
3
Medical optimization
Intravenous antibiotics are administered.
Treats potential secondary bacterial infection of the gallbladder and serves as crucial surgical prophylaxis.
4
Definitive surgery
Laparoscopic cholecystectomy is performed.
Surgical removal of the inflamed gallbladder is the standard of care and definitive cure for acute cholecystitis.

Key Concept

The standard sequential management of acute cholecystitis involves clinical suspicion followed by stabilization, ultrasound confirmation, antibiotic administration, and early surgical intervention.
Question 786Question →

A 50-year-old construction worker is evacuated by helicopter to the trauma center following a localized industrial explosion. The patient weighs 80 kg80\text{ kg}. Paramedics report the incident occurred exactly 2 hours2\text{ hours} prior to arrival. Primary survey reveals a patent airway with no signs of inhalation injury, clear breath sounds bilaterally, and a heart rate of 115 beats/min115\text{ beats/min}. Secondary survey is notable for deep partial-thickness and full-thickness thermal burns covering the entirety of his posterior trunk (including buttocks), his entire left lower extremity, and his entire right upper extremity. Superficial (first-degree) burns are noted on his face but are not blistering. Large-bore intravenous access is established. The trauma team initiates fluid resuscitation using lactated Ringer solution according to current Advanced Trauma Life Support (ATLS) guidelines (2 mL/kg/%TBSA2\text{ mL/kg/\%TBSA} for adult thermal burns).

What should be the initial rate of the fluid infusion (in mL/hr\text{mL/hr}) programmed on the intravenous pump for the time remaining in the first 8-hour post-injury window?

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Answer: 600

Answer

600
The correct calculation requires summing the TBSA (18%18\% posterior trunk + 18%18\% left leg + 9%9\% right arm = 45%45\%), multiplying by 80 kg80\text{ kg} and 2 mL2\text{ mL} (totaling 7,200 mL7,200\text{ mL} for 24 hours), dividing in half for the first 8 hours (3,600 mL3,600\text{ mL}), and dividing by the 66 hours remaining in that window (3,600 mL/6 hr=600 mL/hr3,600\text{ mL} / 6\text{ hr} = 600\text{ mL/hr}).

Step-by-Step Solution

1
Calculate affected Total Body Surface Area (TBSA)
45%45\%
Using the Rule of Nines: Posterior trunk is 18%18\%, left leg is 18%18\%, and right arm is 9%9\%. Superficial burns are not included in TBSA calculations for fluid resuscitation.
2
Calculate total 24-hour fluid requirement
7,200 mL7,200\text{ mL}
Formula: 2 mL×80 kg×45=7,200 mL2\text{ mL} \times 80\text{ kg} \times 45 = 7,200\text{ mL}.
3
Determine fluid volume for the first 8 hours
3,600 mL3,600\text{ mL}
Half (50%50\%) of the total 24-hour volume is administered during the first 8 hours post-injury.
4
Calculate infusion rate for the remaining time in the first 8-hour window
600 mL/hr600\text{ mL/hr}
The injury occurred 22 hours prior to arrival, leaving 66 hours (8−2=68 - 2 = 6) in the initial window. Rate = 3,600 mL/6 hr=600 mL/hr3,600\text{ mL} / 6\text{ hr} = 600\text{ mL/hr}.

Key Concept

Calculation of initial burn fluid resuscitation using the Rule of Nines, the ATLS modified formula (2 mL/kg/%TBSA for adult thermal burns), and adjusting the rate for pre-hospital time elapsed since the injury.
Question 787Question →

A 34-year-old man is brought to the emergency department 20 minutes after a high-speed motor vehicle collision. He was the restrained driver of a vehicle that struck a concrete barrier. On arrival, the patient is confused and diaphoretic. His temperature is 36.5°C (97.7°F), blood pressure is 78/45 mm Hg, pulse is 135/min, and respirations are 24/min. Pulse oximetry shows 97% on room air. The airway is patent, and breath sounds are equal bilaterally. A focused assessment with sonography for trauma (FAST) reveals a large amount of free fluid in the hepatorenal recess (Morison pouch) and splenorenal recess. Which of the following is the most appropriate next step in management?

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Answer: Immediate exploratory laparotomy

Answer

Immediate exploratory laparotomy
Immediate exploratory laparotomy is the correct next step. This patient has sustained blunt trauma and is presenting in hemorrhagic shock (hypotension, tachycardia, altered mental status). In the Advanced Trauma Life Support (ATLS) algorithm, hemodynamically unstable patients with blunt abdominal trauma who have a positive FAST exam (indicating intra-abdominal hemorrhage) must be taken directly to the operating room for an exploratory laparotomy. The goal is to rapidly identify and control the source of bleeding (e.g., splenic or hepatic laceration) before irreversible shock or death occurs.

Step-by-Step Solution

1
Assess the patient's hemodynamic status.
The patient has a blood pressure of 78/45 mm Hg and a heart rate of 135/min, indicating Class III or IV hemorrhagic shock (hemodynamic instability).
Hemodynamic status determines whether a trauma patient can safely undergo time-consuming imaging like a CT scan.
2
Evaluate the results of the primary survey and adjuncts (FAST exam).
The airway is intact, breathing is normal, but the FAST exam shows free fluid (blood) in the abdomen.
The primary survey identifies the most immediate life threats. A positive FAST in the setting of shock confirms intra-abdominal hemorrhage.
3
Determine the definitive next step for hemorrhage control.
The patient requires immediate transfer to the operating room.
An unstable patient with a confirmed intra-abdominal bleed must undergo an emergent exploratory laparotomy to stop the bleeding.

Key Concept

Management of blunt abdominal trauma in a hemodynamically unstable patient
Estimated Time:1m 0s
Question 788Question →

A 7171-year-old woman is assessed by the rapid response team five days after undergoing an elective sigmoid resection with primary anastomosis for recurrent complicated diverticulitis. The nursing staff activated the response due to acute mental status changes and hypotension. Her temperature is 39.4∘C39.4^\circ\text{C} (102.9∘F102.9^\circ\text{F}), blood pressure is 78/48 mm Hg78/48\text{ mm Hg}, pulse is 132/min132/\text{min}, and respirations are 26/min26/\text{min}. Pulse oximetry shows 93%93\% on room air. The patient is lethargic and oriented only to person. Abdominal examination reveals a rigid, board-like abdominal wall with severe diffuse tenderness and absent bowel sounds. A closed-suction pelvic drain, which had been outputting minimal clear fluid, has abruptly filled with 200 mL200\text{ mL} of dark, foul-smelling, turbid liquid. Electrocardiography demonstrates sinus tachycardia alongside 2-mm2\text{-mm} ST-segment depressions in leads II, III, and aVF. Laboratory studies reveal a leukocyte count of 22,000/mm322,000/\text{mm}^3, a serum lactate level of 5.4 mmol/L5.4\text{ mmol/L}, and a serum troponin I concentration of 0.8 ng/mL0.8\text{ ng/mL} (normal: <0.04 ng/mL<0.04\text{ ng/mL}). Intravenous crystalloid resuscitation is initiated. Which of the following is the most appropriate next step in the management of this patient?

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Answer: Exploratory laparotomy

Answer

Exploratory laparotomy
The correct answer is exploratory laparotomy. This patient presents with septic shock and diffuse peritonitis secondary to an anastomotic leak, indicated by the timeline (postoperative day 5) and the sudden appearance of feculent fluid in the surgical drain. In the setting of hemodynamic instability and a rigid abdomen, immediate surgical source control via laparotomy is the definitive and lifesaving intervention. The elevated troponin and ST-segment depressions represent demand ischemia (Type 2 myocardial infarction) driven by the extreme physiologic stress, tachycardia, and hypoperfusion of septic shock. Delaying surgery to investigate or medically manage the secondary cardiac findings is a critical clinical error that significantly increases mortality.

Step-by-Step Solution

1
Evaluate the patient's hemodynamic status and physical examination findings.
The patient is in profound shock (hypotension, tachycardia, altered mental status, elevated lactate) with diffuse peritonitis (rigid, board-like abdomen).
Establishing stability and recognizing an acute surgical abdomen dictates the immediacy of intervention.
2
Identify the most likely source of the patient's condition based on the surgical history and drain output.
The sudden output of foul-smelling, turbid fluid from the pelvic drain on postoperative day 5 strongly indicates a colonic anastomotic leak.
Correlating the timeline (POD 5 is classic for leak) with direct evidence (feculent drain output) confirms the primary diagnosis.
3
Interpret the cardiac findings in the context of the primary diagnosis.
The ST-segment depressions and elevated troponin in a patient with profound septic shock represent demand ischemia (Type 2 myocardial infarction).
Severe physiologic stress, tachycardia, and hypoperfusion lead to a supply-demand mismatch in the myocardium, rather than a primary thrombotic event (Type 1 MI).
4
Determine the definitive management.
Immediate exploratory laparotomy is required.
Hemodynamically unstable patients with peritonitis secondary to a surgical leak require immediate operative source control. Delays for imaging or cardiac evaluation are contraindicated.

Key Concept

Management of postoperative anastomotic leak and secondary Type 2 myocardial infarction
Question 789Question →

A 3535-year-old man weighing 70 kg70 \text{ kg} is brought to the emergency department 2 hours2 \text{ hours} after being rescued from a structural fire. On examination, he is hemodynamically stable, and his airway is secure with no evidence of inhalational injury. He has sustained deep partial-thickness and full-thickness burns involving his anterior chest, anterior abdomen, entire right arm, and the anterior aspect of his left leg. The remainder of his skin is intact. Intravenous access is obtained. According to current Advanced Trauma Life Support (ATLS) guidelines for adult thermal burns, what should be the initial rate of intravenous lactated Ringer solution administration for this patient? (Enter the value in mL/hr\text{mL/hr})

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Answer: 420

Answer

420
The correct initial fluid resuscitation rate is 420 mL/hr420 \text{ mL/hr}. According to the Advanced Trauma Life Support (ATLS) 10th edition guidelines, adult patients with thermal burns should be resuscitated using 2 mL2 \text{ mL} of lactated Ringer solution per kilogram of body weight per percent of affected Total Body Surface Area (TBSA). First, the Rule of Nines is applied: the anterior chest (9%9\%), anterior abdomen (9%9\%), entire right arm (9%9\%), and anterior left leg (9%9\%) yield a 36%36\% TBSA burn. The total 24-hour fluid requirement is 2 mL×70 kg×36=5,040 mL2 \text{ mL} \times 70 \text{ kg} \times 36 = 5,040 \text{ mL}. Half of this volume (2,520 mL2,520 \text{ mL}) must be administered within the first 8 hours8 \text{ hours} from the time of the burn. Because the patient presented 2 hours2 \text{ hours} after the injury, the 2,520 mL2,520 \text{ mL} must be infused over the remaining 6 hours6 \text{ hours}, resulting in a rate of 2,520 mL÷6 hours=420 mL/hr2,520 \text{ mL} \div 6 \text{ hours} = 420 \text{ mL/hr}.

Step-by-Step Solution

1
Calculate the burned Total Body Surface Area (TBSA).
36%36\%
Using the Rule of Nines, the anterior chest is 9%9\%, anterior abdomen is 9%9\%, entire right arm is 9%9\%, and anterior left leg is 9%9\%.
2
Calculate the total 24-hour fluid requirement using the ATLS 10th edition formula.
5,040 mL5,040 \text{ mL}
The current guideline for adult thermal burns is 2 mL×weight (kg)×TBSA (%)2 \text{ mL} \times \text{weight (kg)} \times \text{TBSA (\%)}. Therefore, 2×70×36=5,040 mL2 \times 70 \times 36 = 5,040 \text{ mL}.
3
Determine the fluid volume required for the first 8-hour block.
2,520 mL2,520 \text{ mL}
Half of the total 24-hour calculated volume is given in the first 8 hours8 \text{ hours} post-injury.
4
Adjust the infusion time based on the delayed presentation.
6 hours6 \text{ hours}
The 8-hour block begins at the time of injury. Since 2 hours2 \text{ hours} have already elapsed, the 2,520 mL2,520 \text{ mL} must be infused over the remaining 6 hours6 \text{ hours}.
5
Calculate the required hourly infusion rate.
420 mL/hr420 \text{ mL/hr}
2,520 mL2,520 \text{ mL} divided by 6 hours6 \text{ hours} equals 420 mL/hr420 \text{ mL/hr}.

Key Concept

Management of acute burn fluid resuscitation involves applying the Rule of Nines, utilizing the updated ATLS guidelines (2 mL/kg/%TBSA2 \text{ mL/kg/\%TBSA} for adult thermal burns), and dynamically adjusting the infusion rate for the time elapsed since the injury.
Question 790Question →

Eighteen hours into resuscitation for severe thermal injuries, a 4242-year-old male patient exhibits acute clinical deterioration in the intensive care unit. He initially presented following an industrial fire with full-thickness burns covering 55%55\% of his total body surface area, localized exclusively to his back and bilateral lower extremities. He was intubated upon arrival, and standard Parkland formula-based crystalloid infusion was initiated.

Current assessment reveals a precipitous drop in urine output to 10 mL/hr10 \text{ mL/hr}. Vital signs show a temperature of 38.4∘C38.4^\circ\text{C} (101.1∘F101.1^\circ\text{F}), blood pressure of 82/50 mm Hg82/50 \text{ mm Hg}, and a heart rate of 135/min135\text{/min}. The central venous pressure is elevated at 18 mm Hg18 \text{ mm Hg}. The mechanical ventilator repeatedly triggers high-pressure alarms, with peak airway pressures rising acutely from 25 cm H2O25 \text{ cm H}_2\text{O} to 48 cm H2O48 \text{ cm H}_2\text{O}. On physical examination, the abdomen is tensely distended. Transducer measurement via the urinary catheter demonstrates an intravesical pressure of 34 mm Hg34 \text{ mm Hg}. Which of the following is the most appropriate next step in management?

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Answer: Decompressive laparotomy

Answer

Decompressive laparotomy
The correct answer is decompressive laparotomy. This patient has developed secondary abdominal compartment syndrome (ACS), a known complication of the massive crystalloid resuscitation required for large surface area burns (burn shock resuscitation). The diagnosis is confirmed by an intra-abdominal pressure (measured via the bladder) greater than 20 mm Hg20 \text{ mm Hg} in the setting of new-onset organ failure. The upward displacement of the diaphragm causes high peak airway pressures, while compression of the inferior vena cava decreases venous return, leading to hypotension, elevated central venous pressure, and decreased renal perfusion (oliguria). The definitive, life-saving treatment for ACS with established multi-organ failure is immediate surgical decompression of the abdomen.

Step-by-Step Solution

1
Identify the complication of massive fluid resuscitation.
The patient has received massive crystalloid volumes for a 55% TBSA burn, leading to severe third-spacing and splanchnic edema.
Large-volume resuscitation causes capillary leak and fluid accumulation in the peritoneal and retroperitoneal spaces.
2
Interpret the clinical parameters.
Intravesical pressure is 34 mm Hg (normal < 5-7 mm Hg), indicating severe intra-abdominal hypertension (IAH).
Bladder pressure is the standard surrogate measurement for intra-abdominal pressure. Pressures > 20 mm Hg define abdominal compartment syndrome (ACS) if organ dysfunction is present.
3
Assess for organ dysfunction.
The patient has oliguria (renal), hypotension with elevated CVP (cardiovascular compression reducing venous return), and high peak airway pressures (pulmonary compression via upward diaphragmatic displacement).
The triad of IAH, respiratory compromise, and renal failure definitively establishes the diagnosis of ACS.
4
Determine the definitive intervention.
Decompressive laparotomy must be performed immediately.
When ACS causes refractory multi-organ failure, surgical opening of the abdominal fascia is required to release the pressure and restore organ perfusion.

Key Concept

Secondary abdominal compartment syndrome is a life-threatening complication of massive burn fluid resuscitation, diagnosed by intravesical pressures > 20 mm Hg with new organ dysfunction, and treated definitively with decompressive laparotomy.
Estimated Time:1m 30s
Question 791Question →

A 35-year-old man presents to the emergency department complaining of severe, crampy periumbilical pain and worsening abdominal bloating for the past two days. He has had multiple episodes of bilious emesis over the last 12 hours. His last bowel movement was 3 days ago, and he has not passed flatus for 24 hours. His surgical history is significant for an open appendectomy for ruptured appendicitis 8 years ago.

Temperature is 37.8°C (100.0°F), blood pressure is 135/85 mm Hg, pulse is 98/min, and respirations are 18/min. Physical examination reveals a distended and tympanitic abdomen. High-pitched, tinkling bowel sounds are auscultated. There is diffuse, mild tenderness to deep palpation, but no rebound tenderness, rigidity, or involuntary guarding.

Laboratory results:
- Leukocyte count: 11,500/mm311,500/\text{mm}^3
- Hemoglobin: 15.2 g/dL15.2 \text{ g/dL}
- Blood urea nitrogen: 28 mg/dL28 \text{ mg/dL}
- Serum creatinine: 1.2 mg/dL1.2 \text{ mg/dL}
- Serum lactate: 1.2 mmol/L1.2 \text{ mmol/L} (normal: 0.5−2.2 mmol/L0.5-2.2 \text{ mmol/L})

An abdominal CT scan with oral and intravenous contrast demonstrates dilated proximal small bowel loops measuring up to 4.5 cm4.5 \text{ cm} in diameter. A distinct transition point is seen in the distal ileum. Contrast is visualized within the cecum. There is no bowel wall thickening, pneumatosis intestinalis, mesenteric fat stranding, or free intraperitoneal fluid.

Which of the following is the most appropriate next step in the management of this patient?

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Answer: Enteric tube decompression and intravenous fluid administration

Answer

The most appropriate next step is conservative management with enteric tube decompression and intravenous fluid administration.
This patient presents with a classic adhesive small bowel obstruction (SBO), secondary to his prior open appendectomy. The critical decision in managing an SBO is distinguishing between an uncomplicated obstruction and one complicated by ischemia, strangulation, or perforation. While this patient has mild tachycardia, a low-grade fever, and a mildly elevated leukocyte count, these are common findings in simple SBO due to third-spacing of fluids, vomiting, and physiological stress. The elevated blood urea nitrogen and hemoglobin confirm hemoconcentration and significant dehydration. Most importantly, the physical examination reveals no peritoneal signs (no rebound or rigidity), the serum lactate is strictly normal, and the CT scan shows no signs of bowel compromise. Furthermore, the presence of oral contrast in the cecum explicitly defines this as a partial SBO. Partial SBOs resolve with non-operative management in up to 80% of cases. Therefore, the most appropriate initial step is conservative management, which consists of bowel rest, enteric tube decompression, intravenous fluid resuscitation, and serial abdominal examinations.

Step-by-Step Solution

1
Identify the primary diagnosis based on the clinical presentation and imaging.
Adhesive small bowel obstruction (SBO).
The patient has a history of abdominal surgery, crampy abdominal pain, bilious emesis, obstipation, and a CT scan showing dilated small bowel with a transition point.
2
Assess for critical complications that mandate immediate surgical intervention (e.g., ischemia, necrosis, perforation).
The SBO is uncomplicated.
Despite mild tachycardia and leukocytosis (which are likely due to dehydration and stress, supported by an elevated BUN), there is no peritonitis on physical exam, the serum lactate is normal, and the CT scan lacks ischemic signs like pneumatosis intestinalis or wall thickening.
3
Determine if the mechanical obstruction is complete or partial.
Partial SBO.
The CT scan explicitly reveals oral contrast reaching the cecum, proving that the bowel lumen is not completely occluded.
4
Select the appropriate initial management based on the obstruction characteristics.
Conservative, non-operative management.
Partial, uncomplicated SBOs have a high rate of spontaneous resolution (up to 80%) when treated with bowel rest, enteric (nasogastric) decompression, and intravenous fluid resuscitation.

Key Concept

Uncomplicated, partial adhesive small bowel obstructions (evidenced by oral contrast reaching the colon and absence of ischemic signs) should be initially managed conservatively with enteric tube decompression and intravenous fluid resuscitation.
Question 792Question →

A 65-year-old man presents to the outpatient surgical clinic 6 days after undergoing an emergency laparotomy and omental patch repair for a perforated duodenal ulcer. He reports worsening, throbbing pain at his surgical site that began yesterday. His temperature is 38.2°C (100.8°F), blood pressure is 128/78 mm Hg, heart rate is 90/min, and respiratory rate is 14/min. Physical examination shows a midline abdominal incision closed with surgical staples. The inferior one-third of the incision is erythematous, indurated, and exquisitely tender to palpation. Thick, yellowish fluid is spontaneously draining from between two of the staples in this area. The remainder of the abdominal examination is unremarkable, with normal bowel sounds and no rebound tenderness. Which of the following is the most appropriate next step in management?

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Answer: Remove the surgical staples and open the involved portion of the incision

Answer

The most appropriate next step is to remove the surgical staples and open the involved portion of the incision.
The most appropriate next step in management for a patient presenting with a superficial surgical site infection (SSI) is to remove the staples and open the involved portion of the incision. This patient presents on postoperative day 6 with classic signs of a superficial SSI, including fever, localized erythema, induration, tenderness, and spontaneous purulent drainage. These infections involve the skin and subcutaneous tissue. The definitive treatment is source control, which is achieved by opening the wound, draining the purulent collection, and packing the wound to allow for healing by secondary intention. Systemic antibiotics are generally not required for uncomplicated superficial SSIs unless there are signs of severe systemic illness or extensive surrounding cellulitis.

Step-by-Step Solution

1
Identify the postoperative complication based on the clinical presentation.
The patient has a superficial surgical site infection (SSI), indicated by the fever, localized erythema, induration, and purulent drainage on postoperative day 6.
Superficial SSIs typically present between postoperative days 4 and 7 with classic signs of localized inflammation at the incision site.
2
Determine the primary management strategy for a superficial SSI.
The definitive treatment is source control via mechanical wound opening.
Systemic antibiotics cannot penetrate undrained purulent fluid collections effectively, so physical drainage is the mandatory standard of care.
3
Select the option that provides the necessary source control.
Removing the surgical staples and opening the involved portion of the incision is the correct choice.
This allows the purulent material to drain and the wound to subsequently heal safely by secondary intention.

Key Concept

The primary management of a superficial surgical site infection is immediate source control, achieved by opening the wound and allowing it to heal by secondary intention.
Question 793Question →

Emergency medical services bring a 22-year-old male to the trauma bay following an ejection from a moving vehicle. The patient is semi-conscious, with visible facial trauma and a deformed right lower extremity with surrounding ecchymosis. Arrange the following initial management steps in the correct chronological sequence according to the Advanced Trauma Life Support (ATLS) primary survey protocol.

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Answer

The correct sequence follows the ATLS primary survey ABCDE protocol: Airway, Breathing, Circulation, Disability, and Exposure.
The Advanced Trauma Life Support (ATLS) protocol mandates a sequential approach to trauma resuscitation known as the primary survey (ABCDE). Airway with cervical spine protection is always first, as airway obstruction causes the fastest mortality. Breathing follows to ensure gas exchange. Circulation is third to address shock and perfusion. Disability provides a baseline neurologic assessment. Finally, Exposure ensures all injuries are identified while preventing hypothermia. Skipping or rearranging these steps can lead to missed life-threatening conditions.

Step-by-Step Solution

1
Identify the clinical scenario
The patient is a trauma victim requiring initial evaluation and resuscitation.
Trauma resuscitations follow a standardized algorithm to prioritize the most life-threatening conditions first.
2
Determine the first priority (A)
Airway patency with cervical spine restriction must be evaluated first.
Loss of airway kills more rapidly than any other injury mechanism.
3
Determine the second priority (B)
Breathing and ventilation assessment follows airway management.
A patent airway is useless if the patient cannot adequately exchange gases.
4
Determine the third priority (C)
Circulation and hemorrhage control are assessed next.
Once oxygen is reaching the lungs, the cardiovascular system must be able to deliver it to tissues.
5
Determine the fourth priority (D)
Disability (neurologic evaluation) is performed.
A rapid assessment of neurologic status helps identify severe traumatic brain injury requiring urgent intervention.
6
Determine the final priority (E)
Exposure and environmental control conclude the primary survey.
Full exposure is necessary to find hidden injuries, followed by immediate warming to prevent trauma-induced hypothermia.

Key Concept

The Advanced Trauma Life Support (ATLS) primary survey follows a strict ABCDE algorithm to address the most immediately life-threatening injuries first.
Question 794Question →

A surgical clerkship director is teaching medical students about the evaluation of postoperative fever. To help students prioritize their differential diagnoses, she asks them to recall the classic timeline for various complications. Arrange the following common etiologies of postoperative fever in typical chronological order, from earliest expected onset to latest expected onset.

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Answer

The classic chronological sequence for the onset of postoperative fever is Atelectasis, followed by Catheter-associated urinary tract infection, Deep surgical site infection, and finally Deep vein thrombosis.
The timeline of postoperative fever is classically taught using the 'W's mnemonic. Atelectasis ('Wind') occurs first (days 1-2), followed by urinary tract infections ('Water') from catheter use (days 3-5), surgical site infections ('Wound') as bacteria incubate and form abscesses (days 5-7), and deep vein thrombosis ('Walking') from prolonged immobility (days 7-10).

Step-by-Step Solution

1
Determine the onset time for atelectasis ('Wind').
Atelectasis classically presents on postoperative days 1 to 2.
Early postoperative fever is most commonly associated with pulmonary issues like atelectasis or an expected physiologic inflammatory response to surgical tissue injury.
2
Determine the onset time for a urinary tract infection ('Water').
Urinary tract infections typically manifest on postoperative days 3 to 5.
Foley catheter use and postoperative urinary retention create an environment for bacterial colonization that takes a few days to cause a systemic fever.
3
Determine the onset time for a surgical site infection ('Wound').
Surgical site infections most commonly appear on postoperative days 5 to 7.
It takes several days for contaminating bacteria to incubate and proliferate sufficiently to form an abscess or cause significant cellulitis.
4
Determine the onset time for deep vein thrombosis ('Walking').
Deep vein thrombosis typically presents on postoperative days 7 to 10.
Prolonged postoperative immobility leads to venous stasis, allowing time for significant thrombus formation and potential pulmonary embolism.

Key Concept

The classic mnemonic 'Wind, Water, Wound, Walking' is used to recall the chronological timeline of common postoperative fever etiologies.
Question 795Question →

A 64-year-old man is evaluated in the surgical intensive care unit on postoperative day 8 following a pancreaticoduodenectomy. His postoperative course was complicated by delayed gastric emptying, requiring bowel rest and total parenteral nutrition (TPN) via a right internal jugular central venous catheter. Today, he develops sudden chills. His temperature is 39.4°C (102.9°F), blood pressure is 92/58 mm Hg, heart rate is 124/min, and respiratory rate is 22/min. Physical examination reveals mild erythema at the central line insertion site. The surgical drains continue to output a small amount of non-purulent, clear fluid, and his abdomen is soft and non-tender. His leukocyte count has increased from 10,500/mm³ yesterday to 19,500/mm³ today.

Which of the following are the most appropriate initial steps in the evaluation and management of this patient's acute change in condition? (Select exactly two)

Select all that apply

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Answer: Draw paired blood cultures from the central venous catheter and a peripheral vein; Initiate empiric intravenous broad-spectrum antimicrobial therapy

Answer

The most appropriate initial steps are to draw paired blood cultures from the central venous catheter and a peripheral vein, and to initiate empiric intravenous broad-spectrum antimicrobial therapy.
The patient is presenting with signs of septic shock (fever, tachycardia, hypotension) on postoperative day 8. In the setting of total parenteral nutrition (TPN) via an indwelling central venous catheter and erythema at the insertion site, a central line-associated bloodstream infection (CLABSI) is the most likely diagnosis. The initial management of suspected CLABSI requires obtaining paired blood cultures (one from the catheter and one from a peripheral vein) to determine the differential time to positivity. Concurrently, because the patient is hemodynamically unstable, empiric broad-spectrum intravenous antibiotics must be initiated immediately to cover typical hospital-acquired pathogens, including MRSA and Pseudomonas.

Step-by-Step Solution

1
Analyze the patient's presentation and timeline.
The patient is on postoperative day 8 with a central venous catheter receiving TPN. He presents with new-onset high fever, tachycardia, hypotension, leukocytosis, and mild erythema at the line site, without new abdominal signs.
Establishing the postoperative day and recognizing the presence of foreign bodies (such as a central line) helps narrow the differential diagnosis for postoperative fever.
2
Identify the most likely source of infection.
The most likely diagnosis is a central line-associated bloodstream infection (CLABSI) leading to septic shock.
Fever starting after postoperative day 5 in a patient with an indwelling central line, especially one used for TPN, is highly suspicious for CLABSI, particularly when accompanied by localized erythema and hemodynamic instability.
3
Determine the appropriate diagnostic and therapeutic interventions.
The immediate priorities are obtaining appropriate cultures (paired central and peripheral blood cultures) and administering broad-spectrum empiric antibiotics.
In suspected sepsis, identifying the organism and starting early broad-spectrum coverage are critical to reducing mortality. Catheter removal is also indicated for TPN-associated infections.

Key Concept

Patients with central venous catheters (especially those receiving total parenteral nutrition) who develop fever and hemodynamic instability should be evaluated for a central line-associated bloodstream infection (CLABSI). Immediate management includes paired blood cultures and broad-spectrum empiric antibiotics.
Question 796Question →

Accompanied by her daughter, a 61-year-old female is evaluated in the surgical assessment unit due to three days of worsening left lower abdominal pain, chills, and anorexia. Her past medical history is notable for hypertension and hyperlipidemia. Vital signs show a temperature of 38.8°C (101.8°F), heart rate of 102/min, blood pressure of 128/78 mm Hg, and respiratory rate of 16/min. Physical examination reveals focal tenderness and voluntary guarding in the left lower quadrant, but no generalized rigidity or diffuse rebound tenderness. Laboratory studies demonstrate a leukocyte count of 16,500/mm³ with a left shift. A contrast-enhanced computed tomography scan of the abdomen and pelvis reveals severe sigmoid diverticulitis accompanied by a 6.5-centimeter unilocular fluid collection adjacent to the inflamed bowel segment. Based on current surgical guidelines, arrange the following steps in the most appropriate sequential order for the comprehensive management of this patient.

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Answer

The correct sequence of management for a stable patient with a large diverticular abscess is to first initiate medical management with IV fluids and broad-spectrum antibiotics, followed by percutaneous image-guided drainage of the abscess. The patient is then observed while the drain output decreases and acute inflammation subsides. Finally, an interval elective sigmoid resection is scheduled 6 to 8 weeks later.
The standard of care for a hemodynamically stable patient with complicated diverticulitis involving an abscess > 3-4 cm (Hinchey II) dictates a stepwise approach to minimize morbidity. The patient must first be medically resuscitated with fluids and antibiotics. Next, source control is achieved via CT-guided percutaneous drainage, which avoids operating on acutely inflamed and friable tissue. The patient is then observed clinically as the acute inflammation resolves and the drain output tapers. Finally, to prevent recurrent complicated disease, an interval elective sigmoid resection is performed 6 to 8 weeks later, offering a high probability of successful primary anastomosis without a stoma.

Step-by-Step Solution

1
Diagnose the specific stage of diverticulitis based on imaging.
The patient has a 6.5-cm unilocular fluid collection adjacent to the sigmoid colon, establishing a diagnosis of complicated acute diverticulitis with a macroabscess (Hinchey stage II).
Accurate staging dictates the degree of invasiveness required for initial management.
2
Determine the necessity of immediate medical resuscitation.
The patient requires prompt initiation of bowel rest, IV fluids, and broad-spectrum antibiotics.
Medical stabilization is the universal first step to halt the progression of infection before any procedural interventions are attempted.
3
Select the appropriate modality for source control.
Image-guided percutaneous drainage is selected.
Because the patient is hemodynamically stable without generalized peritonitis, and the abscess is greater than 3 cm, percutaneous drainage is the safest and most effective method to control the source of infection without major surgery.
4
Establish a plan for long-term definitive management.
Plan an interval elective sigmoid resection.
Operating on acutely inflamed bowel often results in a Hartmann procedure (end colostomy). Allowing the inflammation to cool down over 6-8 weeks permits a much safer elective surgery with a primary anastomosis.

Key Concept

Sequential management of Hinchey stage II complicated diverticulitis (diverticular macroabscess)
Estimated Time:2m 0s
Question 797Question →

An 81-year-old woman is transported to the trauma bay via ambulance after sustaining a ground-level fall, striking her left flank against a heavy wooden bench. She has a history of essential hypertension and hyperlipidemia. On initial evaluation, her temperature is 36.4°C (97.5°F), blood pressure is 82/46 mmHg, pulse is 126/min, and respiratory rate is 24/min. Her airway is patent and breath sounds are equal bilaterally. Her abdomen is distended and exhibits severe guarding over the left upper and lower quadrants. Pelvic compression does not elicit instability. She is given 1 L of warmed lactated Ringer fluid via two large-bore peripheral intravenous catheters. Reassessment shows a blood pressure of 80/44 mmHg and a pulse of 130/min. A bedside ultrasound examination demonstrates a large amount of free anechoic fluid in the hepatorenal and splenorenal spaces. Which of the following is the most appropriate next step in management?

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Answer: Transfer to the operating room for celiotomy

Answer

Transfer to the operating room for celiotomy is the most appropriate next step in management.
The correct next step is to transfer the patient to the operating room for a celiotomy (exploratory laparotomy). In the Advanced Trauma Life Support (ATLS) algorithm, patients presenting with blunt abdominal trauma are initially evaluated for hemodynamic stability. This patient presents with class III hemorrhagic shock (hypotension, tachycardia) and remains unstable despite an initial fluid bolus. The presence of free fluid on a focused assessment with sonography for trauma (FAST) exam in an unstable patient is highly indicative of active, life-threatening intra-abdominal hemorrhage. The definitive management is immediate surgical exploration to locate and arrest the bleeding.

Step-by-Step Solution

1
Assess the patient's hemodynamic status based on initial and post-resuscitation vitals.
The patient is hemodynamically unstable (hypotensive and tachycardic) and fails to respond to an initial fluid bolus of 1 L of crystalloid.
Hemodynamic stability dictates the algorithmic pathway for blunt abdominal trauma management.
2
Determine the source of shock based on primary survey adjuncts.
The bedside ultrasound (FAST) reveals free fluid in the abdomen, indicating intra-abdominal hemorrhage as the primary cause of her hemorrhagic shock.
Identifying the anatomical compartment of bleeding rapidly directs definitive therapy.
3
Select the definitive treatment modality.
The correct action is urgent surgical exploration (celiotomy).
A hemodynamically unstable patient with blunt abdominal trauma and a positive FAST requires immediate operative intervention to control hemorrhage.

Key Concept

Hemodynamically unstable patients with blunt abdominal trauma and a positive focused assessment with sonography for trauma (FAST) examination require immediate exploratory laparotomy (celiotomy).
Question 798Question →

A 72-year-old man is evaluated for a new-onset fever on postoperative day 4 following an open repair of a ventral hernia. He has been recovering well, tolerating a regular diet, and ambulating with assistance in the surgical ward hallways. An indwelling urethral catheter was placed prior to surgery and removed on postoperative day 2. Today, his temperature is 38.6∘C38.6^\circ\text{C} (101.5∘F101.5^\circ\text{F}). Blood pressure is 128/76 mm Hg128/76\text{ mm Hg}, pulse is 96/min96/\text{min}, and respirations are 16/min16/\text{min}. Oxygen saturation is 96%96\% on room air. The patient reports feeling slightly fatigued but denies shortness of breath, cough, nausea, or calf pain. He notes that he has been urinating more frequently than usual since the catheter was removed, which he attributes to his postoperative intravenous fluids. Examination shows a soft abdomen with mild tenderness near the surgical incision. The incision is clean and intact with no erythema, induration, or purulent discharge. The lungs are clear to auscultation bilaterally. Which of the following is the most appropriate next step in management?

Show answer & explanation

Answer: Obtain a urinalysis and urine culture

Answer

Obtain a urinalysis and urine culture
The most appropriate next step is to obtain a urinalysis and urine culture. This patient presents with a new-onset fever on postoperative day 4, accompanied by urinary frequency shortly after the removal of an indwelling urethral catheter. This clinical picture is highly indicative of a catheter-associated urinary tract infection (CAUTI). Based on the classic '5 Ws' mnemonic for postoperative fever, 'Water' refers to urinary tract infections, which most commonly occur on postoperative days 3 to 5. The correct approach is to confirm the diagnosis with a urinalysis and identify the specific organism via culture to guide targeted antibiotic therapy.

Step-by-Step Solution

1
Analyze the timing of the patient's postoperative fever.
The fever is occurring on postoperative day 4.
The timing of a postoperative fever is a critical diagnostic clue, commonly remembered via the '5 Ws' mnemonic.
2
Evaluate the patient's symptoms and clinical risk factors associated with this specific timeframe.
The patient had an indwelling catheter removed two days ago and now reports urinary frequency.
Fever on postoperative days 3 to 5 is most frequently associated with urinary tract infections ('Water'), particularly in patients with a history of urinary catheterization.
3
Determine the most appropriate initial diagnostic step based on the suspected etiology.
A urinalysis and urine culture should be obtained.
Confirming the presence of a urinary tract infection and identifying the causative organism is necessary to guide appropriate, targeted antimicrobial therapy.

Key Concept

The timing of postoperative fever provides crucial clues to its etiology (the '5 Ws'). Fever presenting on postoperative days 3 to 5 is most commonly due to a urinary tract infection ('Water'), especially following the use of an indwelling urethral catheter.
Question 799Question →

A 32-year-old male utility worker is brought to the emergency department after sustaining a high-voltage electrical injury while repairing a power line. The incident occurred exactly 2 hours prior to his arrival. On presentation, he is awake, alert, and complains of severe pain in his extremities. His temperature is 36.8∘C36.8^\circ \text{C} (98.2∘F98.2^\circ \text{F}), heart rate is 112/min112/\text{min}, and blood pressure is 110/70 mm Hg110/70 \text{ mm Hg}. Physical examination reveals deep, full-thickness burns involving his entire anterior trunk and his entire right lower extremity. There are also deep, charred entry and exit wounds on his right hand and left foot, though these cover a negligible surface area. His body weight is estimated at 75 kg75 \text{ kg}. A Foley catheter is inserted to monitor urine output, and large-bore intravenous access is obtained. According to the Advanced Trauma Life Support (ATLS) guidelines for high-voltage electrical injuries, what is the appropriate initial intravenous fluid infusion rate (in mL/hour\text{mL/hour}) for this patient?

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Answer: 900

Answer

900
The appropriate initial fluid infusion rate is 900 mL/hour because high-voltage electrical burns require 4 mL/kg/%TBSA for fluid resuscitation, totaling 10,800 mL for this 75 kg patient with 36% TBSA burns. Half of this total (5,400 mL) must be administered in the first 8 hours post-injury. Because 2 hours have already elapsed, the 5,400 mL must be infused over the remaining 6 hours, yielding a rate of 900 mL/hour.

Step-by-Step Solution

1
Calculate the Total Body Surface Area (TBSA) burned using the Rule of Nines.
TBSA = 36%
The entire anterior trunk accounts for 18% and the entire right lower extremity accounts for 18% (18+18=3618 + 18 = 36).
2
Select the correct ATLS fluid resuscitation multiplier for the injury mechanism.
4 mL/kg/%TBSA
High-voltage electrical injuries require 4 mL/kg/%TBSA to ensure adequate diuresis and prevent acute kidney injury from rhabdomyolysis, unlike the 2 mL/kg/%TBSA used for standard thermal burns.
3
Calculate the total estimated fluid requirement for the first 24 hours.
10,800 mL
4 mL×75 kg×36%=10,800 mL4 \text{ mL} \times 75 \text{ kg} \times 36\% = 10,800 \text{ mL}.
4
Determine the fluid volume to be administered in the first 8 hours.
5,400 mL
Half of the total 24-hour calculated volume is given in the first 8 hours (10,800÷2=5,400 mL10,800 \div 2 = 5,400 \text{ mL}).
5
Calculate the target hourly infusion rate, accounting for time elapsed since the injury.
900 mL/hour
The patient presented 2 hours post-injury, leaving 6 hours for the first 8-hour window (8−2=68 - 2 = 6). The rate is 5,400 mL÷6 hours=900 mL/hour5,400 \text{ mL} \div 6 \text{ hours} = 900 \text{ mL/hour}.

Key Concept

High-voltage electrical burns require fluid resuscitation at 4 mL/kg/%TBSA, with half the volume administered over the first 8 hours starting from the time of injury, requiring rate adjustments for delayed presentations.
Estimated Time:2m 0s
Question 800Question →

A 52-year-old man is brought to the emergency department complaining of sudden-onset, excruciating epigastric pain that started 2 hours ago. He has a history of chronic knee osteoarthritis for which he takes high-dose ibuprofen daily. His temperature is 38.2°C (100.8°F), pulse is 118/min, and blood pressure is 92/58 mmHg. The patient is lying completely still on the stretcher. Physical examination reveals a rigid, board-like abdomen with severe diffuse rebound tenderness. An upright chest radiograph demonstrates a crescent of radiolucency under the right hemidiaphragm. Which of the following is the most appropriate next step in management?

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Answer: Emergent exploratory laparotomy

Answer

Emergent exploratory laparotomy is the appropriate next step for a patient presenting with an acute abdomen, hemodynamic instability, and pneumoperitoneum due to a perforated viscus.
The correct answer is emergent exploratory laparotomy. This patient presents with a classic perforated peptic ulcer, supported by his history of NSAID use, sudden-onset severe pain, and rigid, board-like abdomen. The upright chest radiograph showing free air under the diaphragm confirms pneumoperitoneum. In the setting of a perforated viscus, generalized peritonitis, and hemodynamic instability (tachycardia and hypotension), the absolute next best step is immediate surgical exploration for washout and repair of the defect. Any delay increases the risk of severe sepsis and death.

Step-by-Step Solution

1
Identify the patient's key clinical presentation.
The patient has sudden, severe epigastric pain, a history of NSAID use, hypotension (92/58 mmHg), and a rigid abdomen.
Recognizing signs of an acute surgical abdomen is the critical first step in triage.
2
Interpret the diagnostic imaging provided.
The upright chest radiograph shows free air under the right hemidiaphragm.
This finding confirms the presence of pneumoperitoneum, which indicates a perforated hollow viscus, most likely a peptic ulcer in this context.
3
Determine the optimal management based on patient stability and diagnosis.
The patient is hemodynamically unstable and has peritonitis; therefore, immediate surgical intervention is required.
Delaying surgery for further imaging or attempting non-operative management in this setting significantly increases mortality.

Key Concept

Patients presenting with signs of a perforated hollow viscus (e.g., rigid abdomen, pneumoperitoneum) and hemodynamic instability require emergent exploratory laparotomy.
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