阑尾炎(英文)ppt课件

1、1Acute AppendicitisAcute Appendicitis23Anatomy 4Varied anatomyLength: 510 cm, narrow lumenhaustra of colon5EpidemiologyThe most common acute abdomen disease The incidence of appendectomy appears to be declining due to more accurate preoperative diagnosis.Despite newer imaging techniques, acute appen

2、dicitis can be very difficult to diagnose. 6Pathophisiology Simple appendicitisSuppurative appendicitis Gangrenous appendicitisPerforated appendicitisPeritonitisAbscess around the appendixMucocele of appendix7PathophysiologyAcute appendicitis is thought to begin with obstruction of the lumenObstruct

3、ion can result from food matter, adhesions, or lymphoid hyperplasiaAppendix is twisted, and Lumen of appendix is narrow, result in obstructionMucosal secretions continue to increase intraluminal pressure8Etiology 1. The anatomy characteristics2. The tissue features3. fecality, foreign body obstructi

4、on4. Parasites cause the mucosa damage5. adhesion, pressure cause appendix distortedObstruction high pressure limph obstructed, ischemia mucosa damage bacteria invade（70%80%）9Artery The appendix artery has no branches, is easily to be obstacled 10EtiologyEventually the pressure exceeds capillary per

5、fusion pressure and venous and lymphatic drainage are obstructed.With vascular compromise, epithelial mucosa breaks down and bacterial invasion by bowel flora occurs.microbes：Ecoli, streptococcus, Pseudomonas, anaerobe11EtiologyIncreased pressure also leads to arterial stasis and tissue infarctionEn

6、d result is perforation and spillage of infected appendiceal contents into the peritoneum12PathophysiologyInitial luminal distention triggers visceral afferent pain fibers, which enter at the 10th thoracic vertebral level.This pain is generally vague and poorly localized.Pain is typically felt in th

7、e periumbilical or epigastric area.13PathophysiologyAs inflammation continues, the serosa and adjacent structures become inflamedThis triggers somatic pain fibers, innervating the peritoneal structuresTypically causing pain in the RLQ14PathophysiologyThe change in stimulation form visceral to somati

8、c pain fibers explains the classic migration of pain in the periumbilical area to the RLQ seen with acute appendicitis.15PathophysiologyExceptions exist in the classic presentation due to anatomic variability of the appendixAppendix can be retrocecal causing the pain to localize to the right flankIn

9、 pregnancy, the appendix can be shifted and patients can present with RUQ pain16PathophysiologyIn some males, retroileal appendicitis can irritate the ureter and cause testicular pain.Pelvic appendix may irritate the bladder or rectum causing suprapubic pain, pain with urination, or feeling the need

10、 to defecateMultiple anatomic variations explain the difficulty in diagnosing appendicitis17Manifestations Primary symptom: abdominal pain to 2/3 of patients have the classical presentationPain beginning in epigastrium or periumbilical area that is vague and hard to localize 18Manifestations As the

11、illness progresses RLQ localization typically occursRLQ pain was 81 % sensitive and 53% specific for diagnosisMigration of pain from initial periumbilical to RLQ was 64% sensitive and 82% specific19Manifestations Associated symptoms: indigestion, discomfort, flatus, need to defecate, anorexia, nause

12、a, vomitingAnorexia is the most common of associated symptomsVomiting is more variable, occuring in about of patients20Physical ExamFindings depend on duration of illness prior to exam.Early on patients may not have localized tendernessWith progression there is tenderness to deep palpation over McBu

13、rneys point21Physical ExamRovsings sign: pain in RLQ with palpation to LLQObturator sign: passively flex the R hip and knee and internally rotate the hip. If there is increased pain then the sign is positive22Physical examPsoas sign: place patient in L lateral decubitus and extend R leg at the hip.

14、If there is pain, the sign is positive.Rectal exam: pain can be most pronounced if the patient has pelvic appendix23Physical ExamAdditional components that may be helpful in diagnosis: rebound tenderness, voluntary guarding, muscular rigidity, tenderness on rectalFever: another late finding.At the o

15、nset of pain fever is usually not found. Temperatures 39 C are uncommon in first 24 h, but common after rupture24DiagnosisAcute appendicitis should be suspected in anyone with epigastric, periumbilical, right flank, or right sided abd pain who has not had an appendectomyWomen of child bearing age ne

16、ed a pelvic exam and a pregnancy test.Additional studies: CBC, UA, imaging studies25DiagnosisThe WBC is of limited value. Sensitivity of an elevated WBC is 70-90%, but specificity is very low.But, +predictive value of high WBC is 92% and predictive value is 50%CRP and ESR have been studied with mixe

17、d results26DiagnosisImaging studies: include X-rays, US, CTX rays of abd are abnormal in 24-95%Abnormal findings include: fecalith, appendiceal gas, localized paralytic ileus, blurred right psoas, and free airAbdominal xrays have limited use:for the findings are seen in multiple other processes27Dia

18、gnosisLimitations of US: retrocecal appendix may not be visualized, perforations may be missed due to return to normal diameter28DiagnosisCT: best choice based on availability and alternative diagnoses.In one study, CT had greater sensitivity, accuracy, -predictive value 29Special PopulationsVery yo

19、ung, very old, pregnant, and HIV patients present atypically and often have delayed diagnosisHigh index of suspicion is needed in the these groups to get an accurate diagnosis30TreatmentAppendectomy is the standard of carePatients should be given IVF, and preoperative antibiotics Antibiotics are most effective when given preoperatively and they decrease post-op infections and abscess formation31TreatmentThere are multiple acceptable antibiotics to use as long there is anaerobic flora, enterococci and gram(-) intestinal flora coverageOne sample monot