Ossicular necrosis, 1322 Osteochondritis dissecans (OCD), 279 , 302 clinical recognition, 1370 evidences, 1369 –1370 initial assessment/H&P, 1370 magnetic resonance imaging, 1371 f management/diagnostic testing, 1370 –1371 medial femoral condyle, 1370 f Osteogenic sarcomas, 286 , 302 Osteoid osteoma, 302 , 362 Osteolysis, 283 Osteomyelitis, 302 , 362 , 402 , 721 , 1359 antibiotic therapy, 1361 t clinical recognition, 1359 discharge/admission, clinical indications for, 1361 evidences, 1358 –1359 initial assessment/H&P, 1359 magnetic resonance imaging of, 1360 f management/diagnostic testing, 1359 –1361 periosteal activity, in distal fibula, 1360 f treatment goals, 1359 triage considerations, 1359 Osteosarcoma, 279 Otalgia See Ear pain Otitis externa, 389 –390 , 396 , 1329 –1330 , 1329 f–1330 f Otitis media (OM), 157 , 175 , 222 , 225 , 396 , 909 See also Acute otitis media (AOM) chronic/recurrent, 224 Otitis media with effusion (OME), 390 –392 , 1319 Otolaryngology, inner ear injury, 1115 –1116 Otorrhea, 392 Otoscopy, 138 Ottawa Ankle Rules (OARs), 265 , 1204 Ottawa Knee rules, 280 , 403 Out-of-hospital cardiac arrest (OHCA) incidence rate, 43 age-wise, 43 , 44 t demographic studies, 44 etiologies, 44 prevalence of VT and VF, 57 , 57 t survival after, 44 , 46 use of mild hypothermia after, 69 Ovarian and adrenal tumors, 344 Ovarian cyst, 1291 –1292 , 1307 Ovarian dermoids, 1308 f Ovarian masses, 1307 Ovarian tumors, 344 Overuse syndromes acute tibial tubercle avulsion fracture, 1367 f air, CT scan visualization, 1366 f bursitis, 1369 evidences, 1365 –1367 little Leaguer elbow, 1368 –1369 medial epicondylar apophysis, 1368 f medial epicondyle, small avulsion fracture of, 1368 f Osgood–Schlatter disease, 1367 , 1367 f sever disease, 1369 Sinding-Larsen–Johansson disease, 1367 –1368 , 1368 f treatment goals, 1365 Oxygen delivery devices, 49 Oxygen masks nonrebreathing masks, 49 partial rebreathing masks, 49 simple, 49 P Paget–Schroetter syndrome, 286 Pain abdominal, 354 –360 back, 362 –364 chest, 366 –374 ear, 389 –393 limp with, 304 –305 management in oncologic emergencies, 926 –927 pleural, 366 referred, 393 , 510 scrotal, 408 –416 Pain analgesia, 1113 Paliperidone, for schizophrenia, 1442 Pallor, 501 , 886 acute accentuation of, 420 with anemia, 418 t associated with shortened red cell survival, 420 by autoimmune hemolytic anemia, 420 caused by anemia, 417 common causes, 418 t diagnostic approach to, 422 f differential diagnosis, 417 –421 disorders of heme, 419 evaluation and decision, 421 –423 from low hemoglobin level, 420 membrane abnormalities and, 420 from sudden, massive hemorrhage, 421 systemic disorder and, 419 without anemia, 418 t Palmar psoriasis, 470 f Palmoplantar psoriasis, 468 Palpitations, 486 associated with exercise, 425 common causes, 425 t differential diagnosis, 424 –425 , 425 t drug-induced, 426 t etiologies, 424 evaluation and decision, 426 –427 , 427 f life-threatening causes, 425 t pathophysiology, 424 Pancreas tumors, 914 Pancreatic injuries, 1090 –1091 hyperamylasemia, 1090 nasogastric decompression/bowel rest, 1091 Pancreatitis, 358 , 732 –734 clinical indications for admission, 734 clinical recognition, 732 management, 734 treatment, goals of, 732 triage, 733 Panic attacks, 1444 Papilledema, 180 , 341 Papular-purpuric gloves-and-socks eruption (PPGS), 475 , 475 f Papules characteristic appearance, 634 insect bites, 636 , 636 f louse infestation, 637 –638 , 637 f milia, 634 molluscum contagiosum, 634 –635 , 635 f scabies infestation, 637 , 637 f spider bites, 636 –637 , 637 f tick bites, 636 vascular papules and nodules, 638 , 638 f warts, 635 –636 xanthomas, 636 yellow, tan/brown papules, 638 –639 , 638 f Papulosquamous eruptions, 468 –474 Paracoccidioidomycosis, 444 Paradoxical vocal cord movement, 515 Paraesophageal hernia, 1421 –1422 Parainfluenza virus, 572 Paralytic ileus, 87 , 127 –128