approach to diagnosis, 397 f associated with muscle contractions, 395 associated with vascular changes, 394 –395 bad, 394 benign, 394 brain tumor, 398 t–399 t dental abscess and, 396 differential diagnosis, 394 –396 evaluation and decision, 396 –400 history, 396 –398 laboratory and radiographic testing, 399 –400 physical examination, 398 –399 inflammatory conditions and, 395 –396 laboratory and radiographic testing, 399 –400 occipital, 396 pathophysiology, 394 of psychogenic origin, 396 signs and symptoms, 399 t from traction and compression, 396 treatment and disposition, 400 Head and neck tumors clinical assessment, 909 –910 clinical recognition, 909 evidences, 909 goals of treatment, 909 management, 910 Head injuries approach to diagnosing complications, 272 –274 , 273 f clinical assessment history, 270 –271 neurologic examination encompasses, 271 physical examination, 271 –272 radiographic investigation, 272 criteria for discharge with home observation, 274 t differential diagnosis, 268 evaluation and decision, 270 pathophysiology, 268 Head tilt, 329 Health care delivery, Hearing loss acquired sensorineural, 222 –224 common and life-threatening causes, 224 t conductive, 222 congenital sensorineural, 222 differential diagnosis, 222 –224 , 223 t evaluation and decision, 224 –226 , 225 f functional, 224 pathophysiology, 222 Heart murmur characteristics, 228 –229 ancillary diagnostic aids, 229 –230 “seven Ss” of innocent, 229 t common, 233 t differential diagnosis, 227 –230 , 228 t due to congenital heart defects (CHDs), 227 evaluation and decision, 230 –234 of acyanotic infant, 230 , 232 f cardiac murmur, 230 of cyanotic infant, 230 , 231 f examination, 227 –230 general assessment, 227 –228 precordial examination, 228 functional murmurs, 232 history, 227 innocent vs pathologic, 234 t signs and symptoms, 229 Heart palpitations, 424 Heat exhaustion, 690 Heat stroke, 203 , 688 , 690 Heel padding, 1369 Heel walking, 564 Helicobacter pylori infection, 215 Hemangiomas, 317 , 320 –321 , 347 , 1352 , 1352 f Hematemesis, 213 , 215 , 1419 Hematoceles, 411 –412 , 415 Hematochezia, 213 , 218 , 220 Hematologic abnormalities, 692 Hematologic dysfunction, definition, 77 t Hematologic emergencies, 769 anemia, 769 –770 blood loss, 770 –773 decreased red blood cell production, 777 hemolytic anemia, 773 –776 hemophilia, 795 –797 heparin-induced thrombocytopenia, 790 –791 , 791 t hypercoagulability, 798 –801 immune thrombocytopenia, 787 –790 methemoglobinemia, 776 –777 neonatal thrombocytopenia, 790 neutropenia, 785 –787 nonimmune thrombocytopenia, 791 sickle cell disease, 779 –783 , 781 t–782 t transfusion reactions, 801 Hematoma, 1388 Hematometrocolpos, 130 Hematuria, 529 approach to, 238 f causes common, 236 t life-threatening, 236 t principal, 236 t differential diagnosis, 235 evaluation and decision, 235 –239 history, 237 pathophysiology, 235 physical examination, 237 Heme protoporphyrin, 294 Hemiatlas, 330 Hemodialysis, 694 , 876 Hemoglobin, 417 , 419 , 421 Hemoglobinopathies, 420 Hemolytic uremic syndrome (HUS), 152 –153 , 164 , 218 , 233 , 235 , 237 , 420 , 731 –732 , 981 –982 Hemophagocytic lymphohistiocytosis (HLH), 906 , 1018 –1019 , 1019 t Hemophilia, 352 , 795 –797 clinical indications for discharge/admission, 797 clinical recognition, 795 –797 hemostasis, X-linked disorders, 795 management/diagnostic testing compartment syndrome, 797 emergent/major surgery, 797 hematuria, 797 iliopsoas/thigh hemorrhage, 797 patients with inhibitors, management, 795 –796 throat/neck swelling, 797 treatment, goals of, 795 triage, 795 Hemoptysis, 134 , 947 –948 Hemorrhage, 119 –120 , 1257 f, 1314 Hemorrhagic diathesis, 168 Hemorrhagic shock, 39 history and physical examination findings, 76 management source control, 81 mortality following, 84 POCUS findings, 76 Hemorrhoids, 1356 Hemothorax, 1275 –1278 , 1277 f bedside ultrasound, 1277 chest radiograph, 1277 chest tube, 1277 –1278 clinical assessment, 1276 clinical recognition, 1276 disposition, 1278 evidences, 1275 –1276 needle decompression, 1277 open, 1277 tension pneumothorax, 1276 –1277 , 1276 f