Trauma Flashcards
A 25-year-old man is brought to the emergency department after being involved in a motor vehicle collision. Blood pressure is 75/40 mmHg, and vasopressors are administered. Glasgow Coma Scale score is 5. Intracranial pressure (ICP) via ventriculostomy is 35 mmHg. Which of the following is the most appropriate immediate treatment to lower his ICP?
Answers:
A. Neuromuscular Paralysis.
B. Titrate vasopressor for goal systolic blood pressure 90-100.
C. Hypertonic saline by intermittent bolus.
D. Secondary Decompressive hemicraniectomy.
E. Mannitol bolus.
Hypertonic saline by intermittent bolus.
Hypertonic saline via intermittent bolus is considered tier 1 management for intracranial pressure (ICP) control. Mannitol would not be appropriate given the hypotension. Secondary decompressive hemicraniectomy and paralysis are higher tier and can be used after temporizing with hypertonic saline. Although treatment of the hypotension is appropriate, ICP would be more effectively treated with hypertonic saline.
Which of the following is the recommended transfusion ratio for units of red blood cells (RBC), plasma, and platelets (RBC:plasma:platelets) during massive transfusion?
Answers:
A. 1:2:2
B. 2:1:1
C. 1:3:1
D. 1:1:4
E. 1:1:1
**1:1:1
**
The PROPPR trial (randomized controlled) demonstrated that among patients with severe trauma and major bleeding, early administration of plasma, platelets, and red blood cells in a 1:1:1 ratio compared with a 1:1:2 ratio did not result in significant differences in mortality at 24 hours or at 30 days. However, more patients in the 1:1:1 group achieved hemostasis and fewer experienced death due to exsanguination by 24 hours. Even though there was an increased use of plasma and platelets transfused in the 1:1:1 group, no other safety differences were identified between the 2 groups.
Which of the following is the optimal initial agent for rapid reversal of warfarin for emergency neurosurgery?
Answers:
A. prothrombin complex concentrates (PCCs)
B. Factor VIIa
C. Vitamin K
D. fresh frozen plasma (FFP)
E. Factor II
prothrombin complex concentrates (PCCs)
Prothrombin complex concentrates (PCCs) should be considered for emergent use for reversal of coagulopathy in patients with major or life-threatening bleeding. PCC is administered as a small volume, has a quick onset, and results in immediate decrease in INR. Vitamin K1 (phylloquinone) allows for the synthesis of vitamin K-dependent clotting factors de novo, while fresh frozen plasma (FFP) and prothrombin complex concentrates (PCCs) provide supplemental coagulation factors, including proteins C and S in some preparations.
FFP is derived from donor plasma that is rapidly frozen and stored at 18°C or colder. It contains all coagulation factors, as well as fibrinogen, protein C, and vWF. The intrinsic INR of FFP is 1.5, and it has not shown clinical benefit in patients with an INR below 1.7. Human immunodeficiency virus and hepatitis transmission are known risks of transfusion, as well as the development of transfusion-related acute lung injury (TRALI) and allergic reactions. FFP remains in the intravascular space and can precipitate fluid overload, and the evidence for its efficacy is only of low quality.
Recombinant factor VII, rVIIa (NovoSeven) is not recommended as a warfarin reversal agent.
A 42-year-old man has leakage of CSF after undergoing translabyrinthine resection of a vestibular schwannoma. Seven days later, his temperature is 40.0°C (104.0°F). Examination shows hypotension and altered mental status. On pulmonary artery catheterization, cardiac output is 2.4 L/min, pulmonary capillary wedge pressure is 8 mmHg, and systemic vascular resistance is 800 dyne·sec/cm5. The most appropriate management is administration of which of the following agents?
Answers:
A. Norepinephrine 0.1 mcg/kg/min
B. 500 ml 4% albumin
C. Epinephrine 0.01 mcg/kg/min
D. 500-1000 ml crystalloid
E. Vasopressin 0.01 mcgs/min
500-1000 ml crystalloid
This patient has a high fever, hypotension, and altered mental status in the setting of a post-operative spinal fluid leak. It is likely that he has post-operative meningitis. Cardiac output is low at 2.4L liters/minute (normal is 4-8 liters per minute). SVR at 800 dyne·sec/cm5 is on the low end of normal (700-1600) suggesting peripheral vasodilation. PCWP is within
normal range.
This patient is septic and should be started on broad spectrum antibiotics as soon as possible and preferrably after blood cultures are drawn (Dellinger, 2012). Hypotension in sepsis should be treated initially with IV crystalloids (up to 30 ml/kg over the first 3 hours) regardless of PCWP or any other static variable (Michard, 2002). There is little data suggesting that albumin is superior to crystalloid for initial resusitation (Finfer 2004) but albumin is substantially more expensive. Patients who are unresponsive to fluids and/or have pulmonary edema are started on vasopressors. Norepinephine (Levophed) is the vasopressor of choice in sepsis and can be supplemented with vasopressin or epinephrine if needed.
Which of the following interventions to lower intracranial pressure exerts its effect by reducing blood viscosity?
Answers:
A. Lasix.
B. Hypertonic Saline Bolus.
C. Propofol.
D. Mannitol Bolus.
E. Crystalloid bolus.
Mannitol Bolus.
Mannitol has been shown to reduce blood viscosity. Hypertonic saline, crystalloid, Lasix and sedation do not typically do this. Mannitol’s effect is that of osmotically dehydrating the brain. In addition, it is known to decrease cerebrovascular resistance and increase cerebral blood flow. Mannitol may also cause a decrease in blood pressure and should be carefully used in cases of hypotension.
Induced mild hypothermia has been shown to improve neurological outcome in which of the following emergency conditions?
Answers:
A. Traumatic Brain Injury
B. Subarachnoid hemorrhage
C. Stroke
D. Cardiac arrest
E. Intracerebral Hemorrhage
Cardiac arrest
Induced hypothermia, or targeted temperature managment (TTM), remains controversial. While the recent TTM2 trial showed no improvement in mortality with hypothermia after cardiac arrest (PMID: 34133859), previous studies have found evidence of improved neurological outcomes after cardiac arrest with the use of hypothermia (PMID: 11856793, PMID: 11856794, PMID: 31577396). Treatment wth moderate (33 degrees C) vs mild (36 degrees C) hypothermia does not seem to confer a clear benefit (PMID: 24237006). Prophylactic hypothermia for the treatment of severe hypothermia resulted in no benefit (PMID: 30357266), nor did the use of hypothermia to treat elevated ICP after TBI (PMID: 26444221). No evidence suggests improved outcomes after stroke, ICH, or aSAH with induced hypothermia.
Which of the following early physiologic changes would alert the surgical anesthesia team to the possibility of air embolization?
Answers:
A. Bradycardia
B. Hypocapnia
C. Decreased End Tidal CO2
D. Increased End Tidal CO2
E. Hypotension
Decreased End Tidal CO2
An abrupt decrease in end tidal carbon dioxide and development of tachycardia are the earliest indicators of a venous air embolism in patients undergoing general anesthesia. Hypocapnia and bradycardia would indicate another more likely diagnosis. Hypotension can certainly be seen but usually is not the earliest physiologic indicator.
A venous air embolism occurs when air enters the venous system and eventually causes an obstruction in the pulmonary circulation. The gradient between external atmospheric pressure and the intravascular low central venous pressure (CVP) is especially increased by hypovolemia or during inspiration by creating a negative intrathoracic pressure which enhances the possibility of air entry. As CVP may be sub-atmospheric at baseline in up to 40% of patients, those patients in an upright position or those undergoing IR procedures such as hemodialysis catheter placements are particularly susceptible.
A 42-year-old woman is admitted to the intensive care unit with headache, nausea and vomiting, altered mental status, visual disturbances, and a single grand mal seizure. MR imaging shows a widespread T2 hyperintense signal involving the occipital and parietal white matter bilaterally. Which of the following is the most likely diagnosis?
Answers:
A. Venous sinus thrombosis
B. Acute Disseminated EncephaloMyelitis (ADEM)
C. Posterior reversible encephalopathy syndrome
D. CNS vasculitis
E. Posterior circulation stroke
**Posterior reversible encephalopathy syndrome
**
Posterior Reversible Encephalopathy Syndrome (PRES) is characterized by seizures, encephalopathy, headaches, and visual disturbance (Fugate, 2010). PRES is often associated with severe, acute hypertension (70-90% of cases). PRES can also result from drug exposure, especially immunosuppressing agents (tacrolimus, cyclosporine). The pathophysiology behind medication-induced PRES is not well-understood but believed to be similar to the potential mechanisms of hypertensive PRES, including local breakdown of the blood–brain barrier secondary to hyperperfusion causing extravasation of blood and subsequent localized cerebral edema, and endothelial dysfunction secondary to the direct
effects of the immunosuppressant causing vasospasm and brain hypoperfusion. The classic radiographic finding is vasogenic edema in the parietal-occipital lobes. CNS vasculitis may have a similar clinical presentation to PRES but is associated with ischemic lesions on DWI rather than vasogenic edema. A posterior circulation stroke showing such widespread changes would be expected to be associated with cranial nerve palsies, paralysis, and more profound vision loss. Thrombosis of the superior sagittal sinus can also lead to brain edema in a similar pattern, but typical findings would also include hemorrhage, bland infarction, and evidence of thrombus in the sinus. ADEM is a monophasic, demyelinating disease with a fulminant course. It is usually diagnosed in children under age 15 and is more common in males. The demyelinating lesions, as in MS, are typically periventricular.
A 66-year-old woman with a history of hypothyroidism and rheumatoid arthritis presents with a three-week history of worsening diplopia, arm weakness, and difficulty walking long distances. These symptoms are worse in the late afternoon. Physical examination shows normal reflexes and proximal muscle weakness. Vital capacity is 5 cc/kg. Arterial blood gas analysis shows a pCO2 level of 51 mmHg. Administration of which of the following is most appropriate for this patient?
Answers:
A. Decadron 10 mg IV x 1
B. Sodium bicarbonate
C. Plasma Exchange
D. BiPAP
E. Intravenous Immunoglobulin
BiPAP
Myasthenia Gravis (MG) is an autoimmune disease that occurs when patients develop autoantibodies to the acetylcholine or MuSK receptor at the skeletal muscle endplate causing disruption of neuromuscular transmission. On a clinical level, this results in rapid fatigue of the affected muscle groups. Classically, MG starts in the muscles of the face and eye lids leading to droopy eye lids and double vision. Progression over time may lead to difficulty swallowing, weakness in the extremities, and difficultly breathing. Around 20% of MG patients suffer from a respiratory failure event referred to as a myesthenic crisis. Often the cause is linked to a pulmonary infection or medication changes, but in many cases there is no obvious inciting event. Guillain-Barré syndrome can present in a similar manner in terms of respiratory failure and extremity weakness, but usually spares the cranial nerves. Deep tendon reflexes are typically absent in GBS.
MG and GBS are treated similarly with either intravenous immunoglobulin (IVIG) or plasma exchange. Steroids are sometimes used but can exacerbate symptoms. It may take up to 1 month for these treatments to have effect. This patient is in respiratory failure as evidenced by her very low vital capacity and high pCO2. The patient should be initiated on BiPAP
followed by intubation if hypercapnea persists.
Positive end-expiratory pressure (PEEP) causes which of the following?
Answers:
A. Increased ventilation
B. Respiratory alkalosis
C. Increased oxygenation
D. Decreased ventilation
E. Respiratory acidosis
Increased oxygenation
Normal ventilation of the lungs involves the exchange of oxygen (O2) and carbon dioxide (CO2) at the junction between the alveolus and the capillary. Management of mechanically ventilated patients requires an understanding how changes in both O2 (oxygenation) and CO2 (ventilation) affect the bodies physiology to make the necessary adjustments in ventilator settings. For patients that are hypoxemic (low O2 saturation), there are only two ways to adjust the ventilator to increase the oxygen saturation: increase the fraction of expired oxygen (FiO2) or increase positive end-expiratory pressure (PEEP). PEEP is the positive pressure that remains within the airways at the end of the exhalation phase of the respiratory cycle. Based on the principles of Henry’s law, increasing PEEP will increase the solubility of oxygen and its diffusion across the alveolocapillary membrane and therefore increase the oxygen content of the blood. PEEP does not influence ventilation (CO2 exchange), which is primarily affected by respiratory rate and tidal volume. PEEP and its effect on oxygenation do not play a role in respiratory acid-base physiology.
A 45-year-old man with chronic alcoholism presents to the emergency department in acute withdrawal with hypoglycemia and altered mental status. Administration of glucose must be preceded by which of the following?
Answers:
A. Lorazepam
B. Potassium
C. Thiamine
D. Folic Acid
E. Chlordiazepoxide
Thiamine
Chronic alcoholism can lead to failure of absorption of important nutrients including thiamine. Lack of thiamine can lead to Wernicke’s encephalopathy characterized by ataxia, confusion, and ophthalmoplegia. If administering glucose in setting of chronic alcoholism, thiamine must be given prior to this to prevent depletion of thiamine (used in glucose metabolism) to avoid exacerbation of these symptoms. Folic acid and potassium levels may be abnormal but are not directly involved with glucose metabolism.
Patients in alcohol withdrawal can present with symptoms of autonomic overactivity which can be treated with benzodiazepines.
A 23-year-old man with paraplegia due to myelomeningocele develops acute laryngospasm and hypotension during induction of anesthesia for an emergency shunt revision. Which of the following is the most likely cause of these symptoms?
Answers:
A. Latex exposure
B. Endotracheal tube mechanical trauma
C. Neck compression from head positioning
D. Propofol infusion syndrome
E. Opioid overdose
Latex exposure
Approximately 85% of patients with spina bifida will have sensitivity to latex which can be severe and life threatening to some. In this case, the patient’s laryngospasm and hypotension is most likely due to latex exposure. An allergic reaction
could present in similar fashion.
Propofol infusion syndrome can lead to rhabdomyolysis, metabolic acidosis, renal failure, and heart failure for people treated with chronic anesthetic. Acute propofol change can cause hypotension but not laryngospasm. Increased dose of opioid can lead to respiratory failure but not laryngospasm. Positioning of head and neck can make intubation difficult and lead to mechanical trauma or hypoxemia but would not cause hypotension or laryngospasm.
A 67-year-old woman becomes abruptly obtunded (GCS 6) 12 hours after sustaining a middle cerebral artery embolic stroke. Which of the following is the most appropriate immediate management?
Answers:
A. Treat systolic blood pressure to goal < 160
B. Heparin drip for goal PTT 50-60
C. tPA administration
D. Surgical decompression
E. Intubation
Intubation
A GCS drop to 6 requires emergent intubation prior to other interventions. As she is 12 hours out from the event, she is outside the tPA window. Acute lowering of the blood pressure is not appropriate, and heparin should not be started before a CT scan because the patient may have a hemorrhagic conversion or midline shift requiring decompression. Surgical decompression may be required given her history, but intubation and imaging would be appropriate first.
Which of the following classes of organisms most commonly causes ventilator-associated pneumonia?
Answers:
A. Coagulase-negative staphylococci
B. S. aureus
C. E. coli
D. Serratia
E. Candida
S. aureus
The most common pathogens in ventilator-associated pneumonia is usually reported to be S. aureus, although gram negative organisms such as P. aeruginosa, and Acinetobacter species are other common culprits. The other pathogens listed are rarely the primary pathogen in ventilator acquired pneumonia.
A 52-year-old woman with hypertension is evaluated because of a Hunt-Hess grade 4 subarachnoid hemorrhage from a ruptured posterior communicating artery aneurysm. She is intubated for airway protection. Blood pressure is 70/30 mmHg and SpO2 is 75%. Chest x-ray shows bilateral pulmonary edema. ECG shows T-wave inversions in the precordial leads. Transthoracic echocardiography shows apical hypokinesis and an ejection fraction of 20%. Which of the following is the most likely diagnosis?
Answers:
A. Neurogenic pulmonary edema
B. Ischemic cardiomyopathy
C. Aspiration pneumonia
D. Volume overload
E. Takotsubo cardiomyopathy
**Takotsubo cardiomyopathy
**
This patient likely has neurogenic stress cardiomyopathy, also known as Takotsubo cardiomyopaty. Cardiac injury may occur immediately after subarachnoid hemorrhage (SAH) or within hours after aneurysmal rupture. SAH-induced cardiac dysfunction with reduced LV function may lead to congestive heart failure and pulmonary edema. A catecholamine surge
after SAH is thought to contribute to cardiomyopathy. Echocadiography often reveals apical ballooning. T waves inversions are common with Takotsubo cardiomyopathy (up to 65% of cases, mostly in the precordial leads).
Desmopressin (DDAVP) promotes hemostasis through which of the following mechanisms?
Answers:
A. Inhibiting the conversion of plasminogen to plasmin.
B. Inducing the release of von Willebrand factor from endothelial cells. C. Inhibiting the cyclooxygenase-1 enzyme.
D. Increasing the level of circulating fibrinogen.
E. Increasing the levels of coagulation factors II, VII, IX and X.
Inducing the release of von Willebrand factor from endothelial cells.
The synthetic analog of vasopressin, desmopressin (DDAVP), is widely used for the treatment of patients with von Willebrand disease (VWD), hemophilia A, several platelet disorders, and uremic bleeding. DDAVP induces an increase in plasma levels of von Willebrand factor (VWF), coagulation factor VIII (FVIII), and tissue plasminogen activator (t-PA). It also has a vasodilatory action. Its effect on VWF and t-PA as well as its vasodilatory effect are likely explained by a direct action on the endothelium, via activation of endothelial vasopressin V2R receptor and cAMP-mediated signaling. This leads to exocytosis from Weibel Palade bodies where both VWF and t-PA are stored, as well as to nitric oxide (NO) production via activation of endothelial NO synthase.
Which of the following side effects of dexmedetomidine infusion in patients in the intensive care unit is of the greatest concern?
Answers:
A. Hypotension
B. Sedation
C. Hypertension
D. Tachycardia
E. Respiratory depression
Hypotension
Dexmedetomidine is a centrally acting alpha-2-adrenergic receptor agonist frequently used in neurocritical care for sedation. Unlike most other sedative medications (e.g. benzodiazepines, barbiturates, propofol) which act on GABA, dexmedetomidine does not result in respiratory depression. This makes it an ideal sedative of choice for non-intubated patients requiring sedation. However, the central mechanism of dexmedetomidine does result in hypotension in 30-50% of patients which may limit its utility in some patients. Additionally, dexmedetomidine may also result in tachycardia, however, this is typically of lesser concern than hypotension in neurocritical care patients.
Which of the following is the drug of choice for treating malignant hyperthermia?
Answers:
A. Propofol
B. Rocuronium
C. Acetaminophen
D. Dantrolene
E. Succinylcholine
**Dantrolene
**
Malignant hyperthermia (MH) is an autosomal dominate disorder associated with the ryodine receptor gene that can result in severe, potentially life-threatening complications with certain anesthetics. In individuals with a predisposition for MH, exposure to halogenated anesthetics (i.e. sevoflurane, halothane, enflurane, etc.) or succinylcholine (depolarizing paralytic) results in an uncontrolled release of calcium from skeletal muscle resulting in sustained muscle contraction. This results in a depletion of ATP and subsequent increase in O2 consumption and CO2 production. The earliest sign of MH is a rapid, unexplained rise in end-tidal CO2 associated with persistent tachycardia. Additional symptoms of MH include tachypnea, hypotension, rigidity, and fever. Laboratory evaluation may reveal anion gap metabolic acidosis, hyperkalemia, and hypercarbia.
If left untreated, MH can result in cardiac dysrhythmias and cardiac arrest. The treatment for suspected MH is removal of the offending anesthetic agent, hyperventilation with 100% O2, and administration of dantrolene. Dantrolene is a muscle relaxant that acts by inhibiting the release of calcium from the sarcoplasmic reticulum of skeletal muscle. Succinylcholine is incorrect as it is one of the agents that precipitates MH. Rocuronium is a non-depolarizing paralytic and may be used as an alternative paralytic in cases of MH. Acetaminophen may be used as an anti-pyretic in cases of MH but is not the treatment of choice. Propofol is a sedative anesthetic that may be used in patients with MH but is not the treatment of choice.
Which of the following factors is most likely responsible for the characteristic appearance of acute cerebral ischemia on the diffusion-weighted MR image shown?
A. Seizure
B. Hemorrhage
C. Large Vessel Occlusion
D. Vasculitis
E. Hypotension
Large Vessel Occlusion
The diffusion-weighted imaging depicts and MCA territory infarction. The middle cerebral artery (MCA) is the most common artery involved in acute stroke. It branches directly from the internal carotid artery and consists of four main branches, M1, M2, M3, and M4. These vessels provide blood supply to parts of the frontal, temporal, and parietal lobes of the brain, as well as deeper structures including the caudate, internal capsule, and thalamus.
Large vessel occlusions are defined as blockages in the intracranial ICA, M1, M2, A1, intracranial vertebral artery, posterior cerebral artery, or basilar artery. This pattern of diffusion restriction is not typical for vasculitic or watershed infarctions. The pattern of diffusion restriction would not be seen in seizure, hemorrhage, or infection.
A 46-year-old man presents with an aneurysmal subarachnoid hemorrhage. The aneurysm is treated and secured. On post-hemorrhage day 7, a delayed, new ischemic neurological deficit develops from severe, diffuse vasospasm. Pulse is 100/min and regular, and blood pressure is 105/80 mmHg. He has no known cardiac disease. Which of the following is the most effective agent to induce hypertension in this patient?
Answers:
A. Dopamine
B. Norepinephrine
C. Epinephrine
D. Dobutamine
E. Vasopressin
Norepinephrine
Use of vasopressors to augment blood pressure is an important modality of treatment for Delayed Cerebral Ischemia (DCI). Various agents have been used to induce hypertension. Norepinephrine may be a suitable first line choice due to its combination of alpha and beta receptor stimulation, low frequency of tachyarrythmias, and reliable hemodynamic response. Vasopressin is typically reserved for use in refractory DCI patients who need additional vasoactive agents to attain hemodynamic goals. Given normal cardiac function in this patient, dopamine and dobutamine are likely not the best first choice agents and are much more likely to contribute to tachycarrythmias. Dobutamine has can indeed augment cardiac output, however cardiac output augmentation should be used as a second-line hemodynamic intervention once arterial BP has been optimized. Furthermore, milrinone may be a more effective agent to augment cardiac output due to the occurence of beta-receptor desensitization associated with stunned myocardium. Norepinephrine has been shown to be result in better hemodynamic response and lower risk of poor clinical outcome than phenylephrine (PMID: 28319954). However, data remain incosistent on this point (PMID: 32357322), and some providers still favor using phenylephrine.
A 56-year-old man comes to the emergency department with progressive fatigue and ataxia, followed by leg weakness over the past 24 hours. On physical examination, he is tachypneic and can barely lift his legs. Reflexes are absent. On hospital day 2, EMG, nerve conduction velocity studies, and lumbar puncture show no abnormalities. Pulmonary function tests show a vital capacity of 4 cc/kg. Which of the following is the most appropriate treatment for this patient?
Answers:
A. Hydrocortizone 100 mg IV
B. Edrophonium
C. Intravenous immunoglobulin
D. Plasmaphoresis
E. Intubation
Intubation
The clinical description of this patient (ascending paralysis, respiratory failure, and absent DTRs) is suggestive of Guillain- Barré syndrome. EMG and NCS will point to multifocal deyelination, but are often normal in the first few days after onset of motor symtoms (Gordon, 2001).
Classically, CSF analysis shows albumino-cytologic dissociation– high CSF protein with a normal WBC count, but can be normal early in the course of disease. Immunotherapy treatments such as steroids, plasmaphoresis, and intravenous immunoglobulin are often used but do not work immediately.
Edrophonium (Tensilon), an aceylcholinesterse inhibitor, was historically used to diagnose GBS, but not in treatment as its effect is short-lived– around 10 minutes. It has not been available for sale in the United States since 2017.
This patient has a more pressing issue, however– impending resiratory failure. GBS patients with a Forced Vital Capacity (FVC) < 20 cc/kg are at risk for respiratory failure. Patients with an FVC under 15 cc/kg like this patient should be considered for elective intubation.
Prophylactic use of antiepileptic drugs in the acute management of patients with traumatic brain injury has been shown to decrease the incidence of which of the following?
Answers:
A. Overall mortality
B. Disability
C. Late post-traumatic epilepsy
D. Sudden unexpected death
E. Early post-traumatic epilepsy
**Early post-traumatic epilepsy
**
In a large, randomized controlled trial, Temkin (1990) showed that phenytoin administered to a patient with a serious head
injury reduced the incidence of early post-traumatic seizures (within the 1st week of injury) from 14.2% to 3.6% when compared to a placebo. There was no significant reduction in the incidence of late seizures or mortality, however. The same group reported that the use of phenytoin did impair performance on neurobehavioral testing that resolved after discontinuing the drug (Dikmen 1991).
Which of the following prevention efforts has been shown to be most effective in reducing catheter-associated urinary tract infections in hospitalized neurosurgical patients?
Answers:
A. Use of hydrophobic catheters
B. Use of Antibiotics
C. Permanent indwelling catheter placement
D. Suprapubic Catheter Placement
E. Avoidance of indwelling catheter placement
**Avoidance of indwelling catheter placement
**
Avoidance of indwelling catheter placement, or early removal of catheters in conjunction with hospital development of protocols and bundles directed at infection prevention are the most effective means of decreasing rates of urinary tract infections. Permanent catheter placement, frequent antibiotic use, suprapubic catheters, and latex or hydrophobic catheter use would all increase the rates of urinary tract infections compared to avoidance or early removal of indwelling catheters.
A 21-year-old woman is being treated for tuberculous meningitis with a combination of isoniazid, rifampin, pyrazinamide, and ethambutol. She develops symmetric tingling in her hands and feet and decreased reflexes in her ankles. Which of the following is the most likely cause of her symptoms?
Answers:
A. Vitamin B2 deficiency
B. Drug induced hepatotoxicity
C. Ethambutol toxicity
D. Isoniazid toxicity
E. Intracerebral Abscess
**Isoniazid toxicity
**
First line anti-tuberculosis medications include rifampin, ethambutol, pyrazinamide and isoniazid. During therapy, side effect monitoring is important. Isoniazid can lead to peripheral neuropathy causing numbness and tingling in hands and feet as well as sensory loss, painful gait, and loss of ankle reflexes. Pyridoxine (Vitamin B6) supplementation can help limit these effects. Ethambutol has known ototoxicity and all the medications have known hepatotoxicity. Intracerebral abscess may lead to seizure or focal neurological deficit.
A 25-year-old man who has been hospitalized for ten days after a severe motor vehicle collision, but has otherwise been clinically stable, develops a temperature of 39.0°C (102.2°F) and blood pressure of 85/50 mmHg. Which of the following is the most likely cause of this patient’s symptoms?
Answers:
A. Deep Vein Thrombosis
B. Paroxysmal Sympathetic Hyperactivity
C. Drug Fever
D. Pneumothorax
E. Sepsis
Sepsis
The most likely diagnosis in a hospitalized patient after trauma who develops fever and hypotension is infection. The hypotension (SBP< 100) meets criteria for sepsis. Pneumothorax may lead to hypotension and respiratory difficulty without fever.
Paroxysmal Sympathetic Hyperactivity or storming may present with fever and associated hypertension and tachycardia. Deep Vein Thrombosis and Drug Reaction should be considered in evaluation of fever, but hypotension is uncommon.
According to the Surviving Sepsis Guidelines, a sepsis diagnosis requires the presence of infection, which can be proven or suspected, and 2 or more of the following criteria:
* Hypotension (systolic blood pressure < 90 mm Hg or fallen by >40 from baseline, mean arterial pressure < 70 mm Hg) * Lactate > 1 mmol/L
* Mottled skin
* Decreased capillary refill of nail beds or skin
* Fever > 38.3 degrees C, or 101 degrees F
* Hypothermia < 36 degrees C core temperature (<96.8 degrees F)
* Heart rate > 90
* Tachypnea
* Change in mental status
* Significant edema or positive fluid balance (>20 mL/kg over 24 hours)
* Hyperglycemia (>140 mg/dL) in someone without diabetes
* White blood cell count > 12,000 or less than 4,000, or with >10% “bands” (immature forms)
* Elevated C-reactive protein in serum (according to your lab’s cutoffs)
* Elevated procalcitonin in serum (according to your lab)
* Arterial hypoxemia (paO2 / FiO2 < 300)
* Acute drop in urine output (<0.5 ml/kg/hr for at least 2 hours despite fluid resuscitation, or about 35 ml/hour for a 70 kg
person)
* Creatinine increase > 0.5 mg/dL
* INR > 1.5 or aPTT > 60 seconds
* Absent bowel sounds (ileus)
* Platelet count < 100,000
* High bilirubin (total bilirubin > 4 mg/dL
The definition of severe sepsis is sepsis with impaired blood flow to body tissues (hypoperfusion) or detectable organ dysfunction. Severe sepsis may occur with or without sepsis-induced hypotension (e.g., with fever, encephalopathy and renal failure but a normal blood pressure).
The definition of septic shock is severe sepsis with sepsis-induced hypotension [systolic blood pressure < 90 mm Hg (or a drop of > 40 mm Hg from baseline) or mean arterial pressure < 70 mm Hg] that persists after adequate fluid resuscitation. “Adequate” is determined by the estimation of the patient’s pre-sepsis intravascular volume status.
Which of the following is the primary mechanism of action of remifentanil?
Answers:
A. Mu opioid receptor agonist
B. GABA receptor agonist
C. Alpha-2-adrenergic receptor agonist D. Delta opioid receptor agonist
E. NMDA receptor antagonist
**Mu opioid receptor agonist
**
Remifentanil is a short-acting and potent opioid analgesic that acts as a mu opioid receptor agonist. There are five types of opioid receptors, with three (mu, delta, and kappa) being responsible for most of the clinical effects of opioid medications. Various opioid medications (e.g. morphine, codeine, fentanyl) have the greatest affinity to the mu opioid receptor, which is responsible for analgesia, sedation, and respiratory depression. Remifentanil may have some affinity for the delta opioid receptor; however, this is not its primary mechanism of action. The remaining receptors are not involved in the mechanism of action of opioids. GABA receptor agonists (e.g. benzodiazepines and propofol) are anesthetics that primarily result in sedation. Ketamine is a dissociative anesthetic that acts as an NMDA receptor antagonist. Dexmedetomidine is a sedative anesthetic that acts as a selective alpha-2-adrenergic receptor agonist.
A 55-year-old man is admitted to the intensive care unit (ICU) because of generalized weakness and deteriorating pulmonary function. The ICU team strongly suspects organophosphate toxicity. Which of the following is most consistent with the pathophysiology or clinical presentation of organophosphate toxicity?
Answers:
A. Tachycardia and hypotension
B. Constipation and urinary retention
C. Miosis and increased salivation
D. Anhidrosis
E. Sensory loss
**Miosis and increased salivation
**
Organophosphate poisoning causes inhibition of acetylcholinesterase which leads to overstimulation of nicotinic and muscarinic ACh receptors. This can lead to weakness and respiratory difficulty as well as common early symptoms of salivation, lacrimation, urination, defecation, gastric cramps, emesis, and miosis (SLUDGEM). It can also cause bradycardia, hypertension, and increased sweating. Severe neurologic changes can occur including seizures, headaches, and coma.
Sensory loss can be a rare late symptom of organophosphate poisoning.
Which of the following types of rhythm is depicted in the rhythm strip shown?
A. Sinus pause
B. Second degree type 1 AV block
C. Third degree AV block
D. Second degree type 2 AV block
E. First degree AV block
**Second degree type 1 AV block
**
This is a second-degree type 1 AV block, also known as Mobitz I second degree AV block. This condition is a regular sinus rhythm with a progressively prolonging PR interval consistent with an AV conduction delay which finishes with a single, non- conducted P wave. Second-degree type 2 AV block presents as a single non-conducted P wave but WITHOUT progressive prolongation of the PR interval.
Which of the following disorders prolongs both prothrombin time and partial thromboplastin time?
Answers:
A. Vitamin K deficiency
B. Hemophilia A
C. Von Willenbrand’s Disease
D. Hemophilia B
E. Liver disease
Liver disease
Prothrombin time evaluates clotting within the extrinsic and common coagulation pathways and prolongation in PT is associated with medications such as warfarin and other vitamin K antagonists, as well as vitamin K deficiency. aPTT evaluates clotting within the intrinsic and common coagulation pathways and prolonged aPTT is seen in Hemophilia A and B, and rarely with Von Willenbrand’s disease. Liver disease can result in a prolongation of both PT and aPTT.
According to the 2017 fourth edition of the Guidelines for the Management of Severe Traumatic Brain Injury, which of the following topics contained a Level I recommendation?
Answers:
A. Use of Steroids
B. Nutrition
C. Prophylactic Hypothermia
D. Cerebrospinal fluid drainage
E. Decompressive hemicraniectomy
Use of Steroids
The correct answer is use of steroids. The guidelines stated it was a Level 1 Recommendation that the use of steroids is not recommended for improving outcome or reducing intracranial pressure (ICP). In patients with severe traumatic brain injury (TBI), high dose methylprednisolone was associated with increased mortality and is contraindications. Feeding patients to attain basal caloric replacement at least by the fifth day and at most by the seventh day post-injury is recommended to decrease mortality is a level IIA recommendation. An EVD system zeroed at the midbrain with continuous drainage of CSF may be considered to lower ICP burden more effectively than intermittent use is a level III recommendation. Bifrontal decompressive craniotomy is not recommended to improve outcomes as measured by the GOS-E score at 6 months post-injury in severe (TBI) patients with diffuse injury (without mass lesions), and with ICP elevation to values 20 mm Hg for more than 15 min within a 1h period that are refractory to first-tier therapies. However, this procedure has been demonstrated to reduce ICP and to minimize days in the ICU. This is a level IIA recommendation.
Protamine reverses the effects of heparin through which of the following mechanisms?
Answers:
A. Direct binding to heparin
B. Formation of Thrombin
C. Von Willenbrand Factor release
D. Inhibition of Antithrombin III
E. Activation of Direct Clotting cascade
**Direct binding to heparin
**
Intravenous heparin is readily reversible with the use of protamine (Class I evidence).1
Protamine binds to heparin to form a stable salt which does not have anticoagulant properties. This salt is cleared from the system. The ability of protamines to neutralize heparin varies with heparin chain length. Short chain fragments cannot be neutralized with protamine, resulting in incomplete neutralization of anti-factor Xa activity. This explains why protamine has weaker effectiveness against Low molecular weight heparin than unfractionated heparin.
Intravenous heparin is readily reversible with the use of protamine (Class I evidence). Protamine must be administered intravenously to avoid the risk of histamine release and resultant bronchoconstriction and hypotension. Most clinicians use a 1-mg to 100-U algorithm for bleeding immediately following a bolus infusion of heparin. If 30 minutes to 1 hour has elapsed since the intravenous injection of heparin, 0.5 mg of protamine sulfate should be given for every 100 U of heparin, and if 2 hours or more have elapsed since the intravenous injection of heparin, 0.25–0.375 mg of protamine sulfate should
be given for every 100 U of heparin administered.
A 39-year-old man is 10 days status post an aneurysmal subarachnoid hemorrhage. He has developed hypotonic hyponatremia with a serum sodium level of 128 mEq/L. Which of the following is the most important factor in determining this patient’s treatment?
Answers:
A. Urine sodium concentration
B. Volume status
C. Urine osmolality
D. Brain natriuretic peptide (BNP)
E. Thyroid stimulating hormone (TSH) level
Volume status
Hyponatremia is common after aneurysmal subarachnoid hemorrhage (aSAH). Both the syndrome of inappropriate secretion of antiduretic hormone (SIADH) and cereral salt wasting (CSW) can occur after brain injury. Distinguising SIADH from CSW has important treatment implications. CSW often indicates the presence of vasospasm and should be treated with hypertonic saline, while a diagnosis of SIADH may trigger treatment with fluid restriction or even diuresis. Volume status is critical to distinguish these conditions. SIADH is characterized by euvolemic hyponatremia whereas CSW is a syndrome of hypovolemic hyponatremia. Urine osmolality and urine sodium values are elevated in both CSW and SIADH. Brain natriuretic peptide (BNP) is typically normal in SIADH. While BNP can be increased in some cases of CSW, this can be variable and is not often used in clinical practice. While hypothyrodisim can contribute to hyponatremia, this mechanism is distinct from hyponatremia in CSW and SIADH and is unlikely to be the cause of hyponatremia here.
On postoperative day one following resection of an epidermoid cyst, the patient develops altered mental status, fever, vomiting, and nuchal rigidity. Which of the following is the most likely source of the patient’s symptoms?
A. Aseptic meningitis
B. Malignant hyperthermia
C. Post-operative seizure
D. Post-operative hematoma
E. Bacterial meningitis
Aseptic meningitis
The symptom combination of altered mental status, fever, vomiting, and nuchal rigidity one day after resection of an epidermoid cyst should raise concern for aseptic meningitis. This is caused by the caustic and irritative effects of the cyst contents on surrounding tissue and CSF. Although bacterial meningitis can occur after a craniotomy, this is typically in a delayed fashion. Post-operative hematoma is less likely given imaging and post-operative seizure typically presents with neurologic signs in absence of fever and nuchal rigidity. Malignant hyperthermia can cause fever and muscle spasms in post-operative period but is less likely given the clinical scenario.
Isolation of Streptococcus milleri from a brain abscess should prompt which of the following?
Answers:
A. Cerebrospinal fluid analysis
B. Oral cavity inspection
C. Thorough skin examination
D. Bone Marrow Biopsy
E. Ophthalmologic exam
**Oral cavity inspection
**
Streptococcus milleri is normal flora within the oral cavity and gastrointestinal tract. It can lead to distant infection including brain abscess after trauma or severe periodontal disease. If isolated from brain abscess, an examination of the oral cavity should be performed. A thorough skin evaluation and CSF analysis can be helpful if an organism has not been obtained or skin flora is identified. A bone marrow biopsy and ophthalmologic exam are not indicated in an infection with streptococcus milleri.
Which of the following interventions has been shown to prevent radiocontrast-induced nephropathy?
Answers:
A. Statins.
B. N-acetylcysteine plus IV normal saline.
C. IV normal saline.
D. IV sodium bicarbonate.
E. IV lactated ringers.
N-acetylcysteine plus IV normal saline.
Radiocontrast administration remains the third leading cause of hospital-acquired acute renal failure. Clinically, radiocontrast-induced nephropathy (RIN) is defined as a sudden decline in renal function after radiocontrast administration. Typically, the serum creatinine level begins to increase at 24 to 72 hours after the administration of contrast, peaks at 3 to 5 days, and requires another 3 to 5 days to return to baseline. RIN increases the incidence of life-threatening complications such as sepsis, bleeding, and respiratory failure and increases the cost of medical care by extending the hospital stay.
In the past, a variety of therapeutic interventions have been used to prevent or attenuate RIN, including saline hydration,
diuretics, mannitol, calcium channel antagonists, theophylline, endothelin receptor antagonists, hemodialysis, and dopamine. More recently, studies demonstrate a positive impact of fenoldopam (dopamine-1 receptor, dopamine-1 agonist) and the antioxidant N-acetylcysteine in ameliorating RIN.
N-acetylcysteine (NAC), the acetylated variant of the amino acid L-cysteine, is an excellent source of sulfhydryl groups, and is converted in the body into metabolites capable of stimulating glutathione synthesis, promoting detoxification, and
acting directly as freeradical scavengers. Besides, the scavenging effect, NAC could also protect by inhibiting ACE, which has been shown to be involved in experimental RIN.
Prevention of RIN seems possible by omission or reduction of contrast, ameliorating predisposing factors, saline hydration 24 hr before and after exposure, and 600 mg acetylcysteine orally twice daily 24 h before and after exposure.
A large meta-analysis found that the use of N-acetylcysteine plus IV normal saline was effective in preventing contrast- induced nephropathy. The other choices are less effective or not at all.
A conscious, confused patient with a minor head injury has normal findings on a CT scan. Twenty hours after the injury, the patient develops new-onset right-sided hemiparesis. A new CT scan of the head shows no change. Which of the following is the most appropriate next step in management?
Answers:
A. Electroencephalogram (EEG)
B. Non-Contrast CT of the Cervical Spine
C. Non-Contrasted Magnetic Resonance Imaging (MRI) of the Brain
D. Combined CT Angiography (Head and Neck) and CT Perfusion Study (Brain)
E. Catheter Angiogram
Combined CT Angiography (Head and Neck) and CT Perfusion Study (Brain)
CT Angiography of the head and neck combined with a CT Perfusion study should be considered a first-line imaging modality for the workup/diagnosis of an acute stroke or arterial dissection in a patient presenting with trauma. MRI / MR Angiography could also be considered but was not a choice. In the patient with a fixed neurologic deficit, stroke workup should take precedence over the workup for seizure, which is less likely in this patient given the symptomatology. However, if all other imaging remains negative an EEG would be the next appropriate step in the workup. CT of the cervical spine is of little value in this clinical scenario. A non-contrasted MRI of the brain may be diagnostic for acute ischemic event, but does not provide enough information to guide acute treatment. Catheter angiography may be required for treatment, but is not used as a first-line diagnostic modality.
Which of the following drugs best minimizes the acute sympathomimetic symptoms of thyrotoxicosis?
Answers:
A. Digitalis
B. Beta blockers
C. Cholestyramine
D. Levothyroxine
E. Calcium channel blockers
Beta blockers
Symptoms of overt thyrotoxicosis include heat intolerance, palpitations, anxiety, fatigue, weight loss, muscle weakness, and, in women, irregular menses. Clinical findings may include tremor, tachycardia, lid lag, and warm moist skin.
Treatment of thyroid storm has multiple aims: 1. supportive care
2. inhibition of new hormone synthesis
3. inhibition of thyroid hormone release
4. peripheral β-adrenergic receptor blockade 5. preventing peripheral conversion of T4 to T3 6. identifying and treating precipitating factors.
Beta blockers are used for the management of acute sympathomimetic symptoms of hyperthyroidism by providing a peripheral B-adrenergic receptor blockade. The other medications will either harm or have no effect.
Which of the following antiepileptic drugs is associated with hyperammonemia?
Answers:
A. phenytoin
B. carbamazepine
C. lamotrigine
D. Valproic acid
E. levetiracetam
Valproic acid
Valproic acid can lead to elevated ammonia levels due to a deficiency in carnitine. Replacement of carnitine is indicated for treatment. Valproic acid does not commonly cause a severe rise in liver enzymes level but other drugs that do can increase risk of hyperammonemia while on valproic acid.
Carbamazepine can cause leukopenia and in rare cases agranulocytosis and aplastic anemia.
Phenytoin toxicity can cause neurologic symptoms such as diplopia, ataxia, and confusion while side effects of anemia, gingival hypertrophy, and osteopenia can occur with chronic dosing.
Lamotrigine can lead to serious rashes that require discontinuation and hospitalization if serious. Levetiracetam has better side effect profile and can cause drowsiness and fatigue.
A 48-year-old woman with multiple sclerosis underwent placement of an intrathecal baclofen pump several years ago to control spasticity. She is brought to the emergency department with increased spasticity, temperature of 40.5°C (104.9°F), tachycardia, and increased blood pressure. In addition to baclofen, which of the following is the most appropriate medication to administer to this patient?
Answers:
A. Labetolol
B. Propofol
C. Midazolam
D. Dantrolene
E. Nicardipine
Midazolam
A patient presenting with hypertension, fever, and tachycardia who has been on chronic baclofen therapy is concerning for withdrawal. Intrathecal baclofen replacement should be first line treatment and benzodiazepine therapy can be lifesaving in the interim. Dantrolene can help with muscle rigidity but does not treat other symptoms. Although baclofen acts on GABA-b receptors, benzodiazepine effect on GABA-a receptors can decrease withdrawal symptoms and prevent seizures.
The remaining medications can be helpful in treating hemodynamic instability and support of intubated patient if critically ill, but benzodiazepines help prevent decline prior to restoration of baclofen therapy.
A 50-year-old man with acute respiratory distress syndrome is being treated with controlled volume mechanical ventilation following a severe head injury and sepsis. Close monitoring of which of the following is most likely to minimize barotrauma?
Answers:
A. Tidal volume of 6 mL/kg of predicted body weight
B. Peak pressure > 35 cmH2O
C. Plateau Pressure > 35 cmH2O
D. Positive end-expiratory pressure >20 cmH2O
E. pCO2 of 60-70 mmHg
Tidal volume of 6 mL/kg of predicted body weight
Functional lung volume in acute respiratory distress syndrome (ARDS) is significantly reduced, thus typical lung volumes can cause overdistention of the alveoli and compromise the alveolar-capillary interface causing ventilator-associated lung injury. Protective lung ventilation is the current standard of care for mechanical ventilation, based on the ARDS-net trial, which includes low tidal volume ventilation (4-8 mL/kg of predicted body weight, with 6 mL/kg being the commonly used number given this was the intervention arm of the ARDSnet trial) and permissive hypercapnia. The other interventions will either have no effect or be detrimental.
Pericardial tamponade is most commonly associated with which of the following clinical findings?
Answers:
A. Widened Pulse Pressure
B. Hypertension
C. Muffled Heart Sounds
D. Decreased Breath Sounds
E. Bounding Pulses
Muffled Heart Sounds
The most common findings associated with acute cardiac tamponade are hypotension, jugular venous distension, and muffled heart sounds. The key element which determines the clinical presentation is the rate of fluid accumulation relative to pericardial stretch and the effectiveness of compensatory mechanisms. Thus, cardiac tamponade comprises a continuum from an effusion causing minimal effects to one causing circulatory collapse.
Acute or rapid cardiac tamponade is a form of cardiogenic shock and occurs within minutes. The symptoms are sudden onset of cardiovascular collapse and may be associated with chest pain, tachypnoea, and dyspnea. The decline in cardiac output leads to hypotension and cool extremities. The jugular venous pressure rises which may show as venous distension at the neck and head. Acute cardiac tamponade is usually caused by bleeding due to trauma, aortic dissection or is iatrogenic.
The physiology is obstructive in nature and hypertension, widened pulse pressure, and bounding pulses would not be seen. Decreased breath sounds would be expected in pneumothorax, not necessarily cardiac tamponade.
Which of the following is the most common endocrinologic side effect of etomidate?
Answers:
A. Hyperglycemia
B. Hypoglycemia
C. Adrenal insufficiency
D. Diabetes insipidus
E. Thyrotoxicosis
Adrenal insufficiency
Etomidate is a commonly used anesthetic often for the purpose of induction for general anesthesia or in rapid sequence intubation (RSI). The most used agents for induction of anesthesia are propofol, etomidate, midazolam, and ketamine. In neurocritical care the selection of induction agent must be tailored to the clinical situation. Etomidate results in rapid general anesthesia without significant inhibition of sympathetic tone or myocardial function, unlike propofol and midazolam. This results in minimal changes in blood pressure, which is important in many emergent neurologic conditions (e.g. stroke and spinal shock) in which a sudden decrease in systemic pressure may worsen outcomes. Additionally, etomidate decreases cerebral blood flow and metabolic rate, resulting in decreased intracranial pressure and increased cerebral perfusion pressure, whereas ketamine increases the cerebral metabolic rate and ICP and should therefore be avoided in cases with concern for elevated ICP or intracranial mass effect. The most significant adverse effect of etomidate is adrenal cortical inhibition resulting in adrenal insufficiency. This is more pronounced in cases in which an etomidate infusion is used; however, adrenal insufficiency is well documented to last at least 24 hours after even a single dose. There is conflicting evidence that the adrenal insufficiency of etomidate may increase mortality in septic patients and therefore sepsis is a relative contraindication.
Which of the following describes the mechanism of action of propofol?
Answers:
A. Agonist of the D2 dopamine receptors
B. Agonist of the GABA-B receptor
C. Modulation of the GABA-A receptor D. Inhibits presynaptic calcium channels E. Modulation of NMDA receptor
Modulation of the GABA-A receptor
Propofol is frequently used in sedation and general anesthesia and acts by positive modulation and potentiation of the GABA-A receptor.
Baclofen is a frequently used agonist of GABA-B receptors in treatment of muscle spasticity.
Memantine and ketamine are NMDA modulating drugs acting as antagonists.
Cabergoline is a common D2 dopamine receptor agonist used in treatment of prolactinomas and Parkinsons disease. Levetiracetam is an anti-epileptic drug that binds with synaptic vesicles that inhibits presynaptic calcium channels.
Which of the following is the most common causative organism in cases of ventriculoatrial shunt infection?
Answers:
A. E. coli
B. Cutibacterium acnes
C. Coagulase-negative staphylococci
D. S. Aureus
E. P. aeruginosa
Coagulase-negative staphylococci
Most shunt infections are caused by skin flora. The most common pathogen is coagulase negative staphalococcus (S. epidermidis in particular) followed by S. Aureus. Cutibacterium acnes (formally P. Acnes) is a well described but less common pathogen in shunt infections. Gram negative organisms account for less than 10% of shunt infections.
A 3-month-old, 5-kg infant is brought electively to the operating room for an endoscopic sagittal strip craniectomy. Which of the following is the most accurate estimate of the circulating total blood volume of this patient?
Answers:
A. 600 mL
B. 400 mL
C. 700 mL
D. 200 mL
E. 300 mL
400 mL
An infant’s blood volume is 75-80 mL/kg. For a 5 kg child, the blood volume is 375-500mL.
An arterial pCO2 of 25 mmHg with a pH of 7.34 most likely represents
Answers:
A. Pure respiratory acidosis
B. Normal ABG
C. Metabolic acidosis with concomitant respiratory alkalosis.
D. Respiratory alkalosis with metabolic compensation
E. Pure metabolic alkalosis
Metabolic acidosis with concomitant respiratory alkalosis.
This patient has a metabolic acidosis with concomitant respiratory alkalosis. A pH of 7.34 and PaCO2 of 25 indicates a bicarbonate of about 13. Using Winters’s formula, PaCO2 would be expected to be 28 (26-30). Given that this patient’s PaCO2 is lower than this, a respiratory alkalosis is also present. The concomitant presence of a respiratory alkalosis likely explains why this patient’s pH is closer normal than would be expected with a PaCO2 of 25.
A 48-year-old woman has acute onset of left hemiplegia. She is alert, answers questions, and follows commands. A CT scan is shown. Pulse is 80/min, and arterial line blood pressure is 210/110 mmHg. Which of the following is the most appropriate next step in management of this patient?
A. Start Levetiracetam 1000mg q12h
B. 1gr/kg of Mannitol IV
C. Start 3% hypertonic saline infusion
D. Transfuse 1 unit of platelets
E. Acute blood pressure control with SBP goal to 140mmHg.
**Acute blood pressure control with SBP goal to 140mmHg.
**
Per AHA 2015 Guidelines:
1. For ICH patients presenting with SBP between 150 and 220 mmHg and without contraindication to acute BP treatment, acute lowering of SBP to 140 mmHg is safe (Class I; Level of Evidence A) and can be effective for improving functional outcome (Class IIa; Level of Evidence B). (Revised from the previous guideline)
- For ICH patients presenting with SBP >220 mmHg, it may be reasonable to consider aggressive reduction of BP with a continuous intravenous infusion and frequent BP monitoring (Class IIb; Level of Evidence C).(New recommendation)
Elevated BP is very common in acute ICH because of a variety of factors, including stress, pain, increased ICP, and premorbid acute or persistent elevations in BP. High SBP is associated with greater hematoma expansion, neurological deterioration, and death and dependency after ICH. Compared with ischemic stroke, in which consistent U- or J-shaped associations between SBP nadir of 140 and 150 mm Hg and poor outcome have been shown, only 1 study of ICH has shown a poor outcome at low SBP levels (<140 mm Hg).
None of the other options have been shown to improve functional outcome.
A 3-month-old girl is evaluated in the emergency department for a skull fracture. An x-ray film is shown. After an initial observation period, she is sent home. Three months later, she returns to the clinic with a soft, boggy scalp mass in the right parietal region. She is neurologically intact, and is feeding well. Which of the following is the most likely diagnosis?
A. Fibrous Dysplasia.
B. Dermoid Cyst.
C. Leptomeningeal cyst.
D. Langerhan Cell Histiocytosis.
E. Benign Fibrous Histiocytoma.
Leptomeningeal cyst.
This is consistent with a leptomeningeal cyst (growing skull fracture). The other options occur in children but are not associates with recent skull fracture and are less likely in this case scenario.
The initial skull fracture, with its dural tearing and entrapment of the arachnoid membrane or brain tissue within the fracture margin, is the most important factor for growing skull fracture (GSF) pathogenesis. More than half of GSFs occur in persons under the age of 12 months and 90% in persons under the age of 3 years. During the first 2 years of life, rapid growth of the brain and skull occurs; the dura adheres more tightly to the bone and thus is more easily torn when the skull is fractured. In those younger than 3 years old, the skull is thinner, less stiff, and more deformable, and in deforming may also more readily tear the dura. In the early stage of GSF, the main damages to the brain and bone are caused by the injury itself. However, the damages as well as the neurological deficits will increase during the progression of GSF, especially in the late stage.
Which of the following types of rhythm is depicted in the rhythm strip shown?
A. Atrial flutter
B. Sinus tachycardia
C. Normal sinus rhythm
D. Multifocal atrial tachycardia
E. Atrial fibrillation
**Atrial flutter
**
Atrial flutter is electrocardiographically characterized as a supraventricular tachycardia with an atrial rate between 250 and 350 beats per minute. There are no P waves present, only f-waves or “saw-tooth waves”. The R-R interval tend to be regular but can be irregular. Atrial fibrillation is always an irregularly irregular rhythm. Given the lack of P waves, sinus tachycardia and normal sinus rhythm are incorrect.
