Discuss the Aetiology, Pathology and Management of post Operative PyrexiaByDr. AkinniyiNOH-Dala

OutlineIntroductionTemprature PatternsTime Scale of Post Operative PyrexiaAetiologyPathogenesisManagementConclusion

IntroductionDefinition: Elevation of body temperature above normal base line value(37.2+0.50C) in the post operative period.T0C=4hrly, 38.3, 41.0, 430CExclusion: Ongoing pathologic process with associated pyrexiaIndicatorProblems: Non specific indexAim: Early identification of cause Prompt definitive Rx.

Temperature PatternsNormal(36.6-37.2+0.40C)Constitutional hyperthermiaAbnormal: subnormal, hypothermia, pyrexiaTemperature ChartsPersistent, Intermittent, RemittentQuotidian, Quartan, Tertian, Erb Stein

Time scale of post operative pyrexiaFirst 24hrsSystemic response to traumaDrug RxnsTransfusion RxnsPre-existing infection/septicaemia24-72hrsPulmonary atelectasisChest infection3-7 daysChest infectionSWIIntraperitoneal sepsis

UTIAnastomotic leak7-10 daysDVTPulmonary embolus

Aetiology Metabolic response to traumaTransfusion RxnsInfestationInfection: uti, swi, rti, iv-devicesOngoing pathologic processSurgical complications Anastomotic leak Thyroid crisisAnaesthetic complications: Malignant hyperthermiaDrug Rxns

PathogenesisA: Metabolic response to traumaNeuroendocrine response to afferent visceral stimulationPath waysChemical mediators cutaneous nociceptors brainstem autonomic afferent endocrine/metabolic XngesPain somatic/association areas hypothalamus hypothalamic/pituitary rlsHypovolaemia;dehydration;fasting- brain stem baro/ chemoreceptors(area postrema)Anxiety/change in sleep pattern alteration in circardian rythm

Endocrine responses: - catabolic hormones-cortisol/adrenalin, - - anabolic hormones-GH, insulin, LH, FSH*T3/T4

B: Alteration in hypothalamic thermoregulatory function

Endotoxins/ Pyrogens Inflammatory Cell Activation Endogenous pyrogens (IL-1,IL6,TNF,IFN,IFN) Circumventricular organ (OVLT) Hypothalamus (Preoptic area) >>synthesisPGE2

C: Abnormal metabolism of skeletal muscleRyanodine receptor defect Alteration in intracellular Ca2+ metab

ManagementHx: complain: fever/cold sensation/rigorTime of onsetPattern/periodicityComplication; convulsion, altrd sensoriumConstitutional symptomsPossible aetiologyPreoperative diagnosisExtent/Nature of surgeryComorbidity (D/M,HIV,Scdx,Asthma,COPD, etc)Review of systems (Resp,Git,Genito/uri,cvs,cns)

Examination:General:palor,icterus,hydratn,petechiae..Vital signs(T0C Vs charts)Systems Resp,Cvs,Git,Genito/urinary,Cns,MssDressings,drainsObservation charts(pre,intra,post op)Rxt Charts

Investigations: Fbc+Esr, Blood film, septic work-up,Euc Ecg,Echo,CXR,Blood gas analysis, urinalysis,Rbs/FbsSeptic work-up-Throat swab-Sputum -Blood-Urine-Lumbar puncture-Wound swab

Treatment Palliative/ConservativeLight colthing+aerationTepid spongeWarm bathNSAIDS (pcm,dypirone,ibuprrofen,asa)IVFNutritional rehabilitation

Defitive Based on identified causeMetabolic responsePlasmodiasisTransfusion RxnSeptacaemiaAnastomotic leaksThyroid crisisDVT/microembolismMalignant hypertermiamonitoring

Conclusion Post operative pyrexia is of variable aetiology. Hence the need for the attending clinician to identify clearly possible cause and institute appropriate treatment. THANKS