A 79-year-old woman is hospitalized after a fall that resulted in a left femoral neck fracture. She tripped over her dog while cleaning her home, hit her head on a bookshelf, and landed on her left side. Prior to this she had been in her usual state of health; her other medical issues include obesity, type 2 diabetes mellitus, hypertension, chronic kidney disease, and hypothyroidism. The patient lives at home by herself. She has smoked a pack of cigarettes daily for 38 years. She drinks alcohol every weekend. Results of the patient's initial workup in the emergency department demonstrated the left femoral neck fracture, creatinine of 2.0 mg/dL, and a negative noncontrast head CT. She was admitted to the hospital and the following day underwent surgical repair. The procedure was uncomplicated. However, on postoperative day 3 the patient is noted to be uncomfortable and mildly agitated. She is unable to coherently explain her symptoms. Current medications include prophylactic subcutaneous heparin, insulin glargine, omeprazole, hydrocodone, and levothyroxine. Temperature is 37.7 C (99.9 F), blood pressure is 104/68 mm Hg, pulse is 114/min, and respirations are 28/min. Pulse oximetry is 86% on room air. Examination shows equal round and reactive pupils. Lung examination demonstrates decreased breath sounds at the bilateral bases. Heart rhythm is regular with normal S1 and S2. The surgical incision shows no surrounding erythema or purulent drainage. The patient follows commands and moves all extremities except the left leg. Laboratory results are as follows:
Troponin I is undetectable. Chest x-ray shows slight bibasilar atelectasis without focal consolidation, pleural effusion, or pulmonary edema. ECG shows sinus tachycardia but is otherwise unremarkable.
Ventilation-perfusion scan shows high probability for pulmonary embolism. The patient is started on intravenous heparin. The next day, the nurse reports that the patient has a fever. The patient still has some chest pain but her shortness of breath and mental status are improved. There is no cough, abdominal pain, nausea, vomiting, diarrhea, dysuria, urinary frequency, or headache. Temperature is 38.3 C (101 F), blood pressure is 121/73 mm Hg, pulse is 102/min, and respirations are 22/min. Oxygen saturation is 92% on 2 L of oxygen by nasal cannula. She does not appear ill. The lungs are clear to auscultation. The abdomen is soft and nontender. Neurologic examination is nonfocal. The operative site is healing well without erythema or purulence. The patient's 2 peripheral IV lines have no evidence of infection. Indwelling urinary catheter is draining clear yellow urine. Laboratory results are as follows:
Chest x-ray shows no new abnormalities. Urinalysis is normal. Blood cultures are sent. Which of the following would be the most appropriate next step for this patient?

Question

A 79-year-old woman is hospitalized after a fall that resulted in a left femoral neck fracture.  She tripped over her dog while cleaning her home, hit her head on a bookshelf, and landed on her left side.  Prior to this she had been in her usual state of health; her other medical issues include obesity, type 2 diabetes mellitus, hypertension, chronic kidney disease, and hypothyroidism.  The patient lives at home by herself.  She has smoked a pack of cigarettes daily for 38 years.  She drinks alcohol every weekend.  Results of the patient's initial workup in the emergency department demonstrated the left femoral neck fracture, creatinine of 2.0 mg/dL, and a negative noncontrast head CT.  She was admitted to the hospital and the following day underwent surgical repair.  The procedure was uncomplicated.  However, on postoperative day 3 the patient is noted to be uncomfortable and mildly agitated.  She is unable to coherently explain her symptoms.  Current medications include prophylactic subcutaneous heparin, insulin glargine, omeprazole, hydrocodone, and levothyroxine.  Temperature is 37.7 C (99.9 F), blood pressure is 104/68 mm Hg, pulse is 114/min, and respirations are 28/min.  Pulse oximetry is 86% on room air.  Examination shows equal round and reactive pupils.  Lung examination demonstrates decreased breath sounds at the bilateral bases.  Heart rhythm is regular with normal S1 and S2.  The surgical incision shows no surrounding erythema or purulent drainage.  The patient follows commands and moves all extremities except the left leg.  Laboratory results are as follows:
 Troponin I is undetectable.  Chest x-ray shows slight bibasilar atelectasis without focal consolidation, pleural effusion, or pulmonary edema.  ECG shows sinus tachycardia but is otherwise unremarkable.
Ventilation-perfusion scan shows high probability for pulmonary embolism.  The patient is started on intravenous heparin.  The next day, the nurse reports that the patient has a fever.  The patient still has some chest pain but her shortness of breath and mental status are improved.  There is no cough, abdominal pain, nausea, vomiting, diarrhea, dysuria, urinary frequency, or headache.  Temperature is 38.3 C (101 F), blood pressure is 121/73 mm Hg, pulse is 102/min, and respirations are 22/min.  Oxygen saturation is 92% on 2 L of oxygen by nasal cannula.  She does not appear ill.  The lungs are clear to auscultation.  The abdomen is soft and nontender.  Neurologic examination is nonfocal.  The operative site is healing well without erythema or purulence.  The patient's 2 peripheral IV lines have no evidence of infection.  Indwelling urinary catheter is draining clear yellow urine.  Laboratory results are as follows:
 Chest x-ray shows no new abnormalities.  Urinalysis is normal.  Blood cultures are sent.  Which of the following would be the most appropriate next step for this patient?

Quizplus · Accepted Answer

Explanation: In general, any patient with a body temperature ≥38.3 C (101 F) is considered to have fever. Although fever often indicates the presence of infection, there are numerous other causes of fever (eg, rheumatologic disease, malignancy, medications). Acute pulmonary embolism (PE) is estimated to cause fever in approximately 15% of cases, possibly due to tissue necrosis in the setting of pulmonary infarction. This patient's high pretest probability of PE, combined with a high-probability ventilation-perfusion scan, confirms the diagnosis of acute PE, which is the most likely cause of her fever. The improvement in her clinical status (eg, heart rate, blood pressure, respiratory rate) with intravenous heparin, combined with stable blood leukocytes and absence of clinical evidence of infection (eg, consolidation on chest x-ray, incisional purulence, peripheral line erythema, abnormal urinalysis), makes concomitant infection unlikely. Collection of blood cultures is reasonable; however, continued treatment for acute PE without initiation of antibiotics is most appropriate. (Choices B and C) Initiation of antibiotics for community- or hospital-acquired pneumonia is not appropriate in this patient with no evidence of consolidation on chest x-ray and no cough or sputum production. The fever and ongoing supplemental oxygen requirement are explained by acute PE. (Choice D) Clostridium difficile colitis is a potential cause of fever in hospitalized patients; however, the absence of diarrhea, abdominal tenderness, and recent antibiotic use in this patient makes the diagnosis very unlikely. (Choice E) Fever and ongoing mild tachypnea and tachycardia are readily explained by acute PE; therefore, empiric antibiotics are not appropriate in this clinically stable patient with no other evidence of infection. Educational objective: Acute pulmonary embolism is estimated to cause fever in approximately 15% of cases; therefore, fever in these patients is not an indication for antibiotics in the absence of other evidence of infection (eg, consolidation on chest x-ray, incisional purulence, peripheral line erythema, abnormal urinalysis). References: Guidelines for evaluation of new fever in critically ill adult patients: 2008 updated from the American College of Critical Care Medicine and the Infectious Diseases Society of America. (http://www.ncbi.nlm.nih.gov/pubmed/18379262) Fever in acute pulmonary embolism. (http://www.ncbi.nlm.nih.gov/pubmed/10631196)

A 79-Year-Old Woman Is Hospitalized After a Fall That Resulted