This document provides information on post-operative fever, including its definition, causes, signs and symptoms, diagnostic workup, and treatment. It notes that fever developing within 24 hours of surgery is usually not due to infection, while fever developing after post-operative day 2 is usually infectious. The diagnostic workup of post-operative fever involves examination of the surgical site and other body systems, along with blood and urine cultures. Treatment is directed at the underlying cause, which could be infectious such as wound infection or non-infectious such as pulmonary embolism.

1. Prof. M.C.Bansal.
Founder Principal &controller; Jhalawar Medical
College Jhalawar.
Ex. Principal & Controller; Mahatma Gandhi
Medical College & Hospital; Sitapura, Jaipur

2.  Definition Fever is the rise of normal core temperature of an individual that
exceeds the normal diurnal variation and is accompanied by an increased
hypothalamic setup.
 DiurnalVariation in 18-40 years of age—
MeanTemperature : 36.8+/- 0.4 C (98.2+/- 0.7 F ). ;being low at 6 AM –36.2 c or98.0 F
and highest at 4-6pm in the range of 37.7 c or 98.9 F.
Temperature > 38C(100.4 F )recorded at two occasions at the interval of 4hrs apart ,
excluding 1st 24 hrs after surgery or any one temperature recording more than 38.6 c
( 101.5 F ) is taken as post operative fever.
Incidence varies widely from 14-91 % .
THIS MAY BE INFECTIOUS / NONINFECTIOUS.
80-90 % patients developing temperature with in 24hrs after operation are not infected
, but patients who develop fever on /5th post operative day(80-90 % ) usually have
commonly identifiable infection .
Infection is definite if it develops after 2days of surgery.

3.  Shivering;
 Chills– may be alternate to feeling of hot;
 General Malaise;
 Somnolence;
 Anorexia;
 Arthralgia , myalgia, skin sensitivity to touch ;
 Absence / presence of sweating;
 Skin rash;
 Increased pulse rate / BP.

4.  Time related causes described here are only guidelines
and do not serve as rule. On many times there is temporal
overlap in the causes described –5Ws
 POD 1-2 Wind (respiratory ) atelectasis develop within
24-48 hrs . Aspiration pneumonia, ventilator associate
pneumonia .
 POD3-5Water—UTI, specially in catheterized patient.
 POD5-6W(veins) , wings , walking –DVT , Iv cannula site
plebitis , IM, injection abscess.
 POD5-7 wound– check for wound infection ,drainage ,
alternate sutures removal , swab culture and diagnose
serious problem such as necrotizing fascitis and peritonitis
due to intestinal leak ( internal wound).
 POD 7+ Wonder if ? Drug induced—drug reaction ,
drugs used intra / post operative / transfused blood or
blood products , anti inflammatory agents etc.

5. Sinusitis Thyroid disorders Meningitis
Seasonal infections--
Pharyingitis, Swine Flue
malaria , Dangu etc.
Adrenal Insifficiency Medication s
Infected central catheter Pheochromocytoma **Drug Fever associated with
skin rash/ eosinophilia--
Ventilator –associate
Pneumonia
Myocardial infarction ----Antiepileptics—phenytoin,
Infected Hematoma Pulmonary Embolism --- Antibiotics beta lectum
s, sulphas , piperacillin
,tezobactam.
Acute gout / flare-up . Neuroleptic malignancy
tumor
---Anti inflammatory drugs –
Endomethacin,
AcuteAlcohol withdrawal Intra cranial pathologies --- Intra operative drug –
Succinyl chloride

6.  Malignant Hyperthermia  rare
 dominantly transient
 genetic disorder triggered by administration of succinyl
chloride
 occurs with in ½ an hour of its administration , but may
persist for < 10 hours.
 BP unstable , rise in heart rate , fever may shoot up to 41-
42 C .
 Muscle rigidity , acidosis, hypoxia cardiac arrhythmia
develops .
 Treatment is to stop all anesthetic drugs , hyper
ventilation, O2.
 Initiate cooling , and diuresis to prevent precipitation of
myoglobin . Inject dantrolene sodium and procainamide.

7.  Adrenal Insufficiency-Typically occurs in patient
who are taking corticosteroids for a long duration ;
owing to suppression of endogenous steroids
(hypothalmo- pituitary –adrenal axis ). Fever ,
refractory fall in BP may develop . Steroid
supplementation in time will resolve the problem.
 Pulmonary embolism  usually presents as
hemodynamic sudden post operative hemodynamic
instability and collapse . Fever, although uncommon ,
may be present.
 AlcoholWithdrawal  frequently presents with fever ,
prompt recognition and treatment prevents excessive
morbidity and mortality.

8.  Myo necrosis –
 common due to wound infection
 Clostridium species or group A Strepto –cocci.
 It is a surgical emergency
 patient presents with shock, tachycardia, fever and septicemia
with in 24 hours after operation.
 Di9agnosis is easy if dressing is opened and wound is examined .
Thin brownish copious malodorous discharge is present .Take
swab for culture and sensitivity.
 Skin may be discolored , subcutaneous crepitations , bullae
formation .Patient has severe pain, restlessness and local
tenderness. If not treated immediately patient may have vascular
collapse, acute renal failure , haemoglobinuria and jaundice.
 Wide excision of all infected and necrosed tissue , high dose of C.
penicillin 20 lacs 6hrly after AST / tetracyclines is mandatory.
 D/D – metastastic Myonecrosis from adeno carcinoma of bowel

9.  Necrotizing Fascitis
 occurs due to wound infection by poly microbes–
haemolytic strepto cocci, staphylococcis anaerobes or
mixed bacteria.
 Necrosis of superficial fascia results ; underlying
muscle are spared .Toxicity is more severe thanWBC
counts / fever / hypothermia , hypotension
,tachycardia and lethargy.
 Locally the wound is dusky with subcutaneous edema
, induration, crepitations , hyperesthesia and bullae
formation in skin .
 Haemoconcentration ,hypokalemia , hemolysis,
hyperbilrubinaemia develop at faster rate.
 Hepatic, renal pulmonary insufficincy soon develop
and patient is in state of septic shock.

10.  Aggressive treatment started as in cases of major
degree burns.
 Predisposing factors include --- diabetes , obesity,
trauma , alcoholism , immunosuppressive state,
hypertension , peripheral vascular disease , IV drug
abuse and addiction .
 A wide excision and debridement / re debridement is
done .
 Iv fluid therapy and nutrition with correction of
electrolyte imbalance and broad spectrum antibiotics
are started ; to be changed as soon the c/s reports are
available.

11.  Intestinal Leak It occurs early / late from devitalized
/ crushed intestine during dissection from pelvic
tumors / leaking anastomosis site.
 Diagnosed by suspicion / flat plate abdomen in
standing posture for gas under diaphragm.
 Manage by -- exploratory laparotomy , repair of the
damaged gut , peritoneal toileting and drainage ,
blood transfusion , antibiotics , resuscitation with fluid
,electrolytes minerals , vitamin supplementation .
Ketoacidocis is prevented by ensuring adequate total
parenteral nutritional therapy; till oral feeding is
suspended .

12.  A care full review of history , investigations ,pre / intra
, post operative sequence of events .
 Through general physical, systemic and operative site
examination , Consultation with physician / general
surgeon / necessary investigations are the key points
in prompt diagnosis of post operative fever.
 An early , timely and appropriate diagnosis ,
immediate treatment helps in minimizing the
mortality and morbidity
 The presence of non infectious cause of fever does not
exclude the possibility of infective reason as both
may co –exist.

13.  Fever associate with diarrhoea and central abdominal
pain---- Enterocolitis due to c Clostridium difficile.
 Calf pain & tenderness--- DVT .
 Cough with sputum , breathlessness ---Pulmonary
infection .
 Urinary frequency , dysurea, haematurtia , urgency supra
pubic and loin pain ----UTI / Pyelonephrytis.
 Site of pain ---helps in localizing the infection ---wound , IV
cannula , catheter site . Intense pain at wound ,
restlessness with fever may be due to clostridium
myonecrosis.
 Fever with delirium ---- acute alcohol withdrawal .
 Rigors and chills ---atelectasis , malaria / pyelonephritis.
 Headache , projectile vomits, stiff neck----Meningitis.
 Pain at IM injection site-----injection abscess

14.  Previous H/O pyrexial illness ---Malaria,TB, Sinusitis ,UTI
,pulmonary disease( empyema, plueral effusion bronciectasis ).
 Local infection--- vaginal vaginosis, cervicitis , infected fibroid /
malignant legion/ decubitous ulcer in case of prolapse , skin
infection at the site of skin incision etc
 Family or Personal H/O malignant hype pyrexia , thyroid disorder ,
IV drug abuse , alcohol / tobacco intake , obesity , Pre operative
transfusion of blood , fluids . Drugs and drug reaction.
 Patients who are more susceptible ---- obese , diabetic , Immuno
compromised , taking chemo / radiotherapy , Corticosteroids ,
debilitating disease, malnutrition , renal / liver insufficency ,
extremes of age ( old aged ) and BP, cardiac valular disease.

15.  Date of surgery ---exact Post operative day and onset
of fever .
 Its type and duration ,
 Use of Implants—mesh
 Type and duration of preoperative antibiotics given .
 Pattern of onset of symptoms on which Post
operative day . Existing symptoms prior to surgery ,
investigations / any treatment given and its response .
 Any complication during operation / anesthesia.
 H/O prolonged ventilation .
 Left over packing , swabs or instruments / poor
debridement / excision of infected , nacrosed tissue /
un recognized / over looked injury to gut.

16.  Monitor vital parameters .
 If tachycardia is out of proportion to rise in
temperature is an ominous sign as in severe sepsis ,
associated with hypotension and oliguria.
 Tachypnoea --- pulmonary cause .
 Pattern , trend and its flctuation should be noted.
 Detailed examination of wound– color of skin ( dusky ,
red, blue/black , indurations , discharge(amount,
color , odor , frothing ) , tenderness, necrosis of edges,
bulla , crepitations.
 if any ,silent dehiscence of wound , presence of
cellulitis , fascitis, abscess, haematoma, gas gangrene
hyperaesthesia, spreading erythematous streaks.

17.  In early stage of wound infection, there is
swelling ,warmth ,redness peri wound edema
and increasing tenderness .
 Later there are more signs of stephylococcal
infection ---maximum erythema and fluctuation
; while with enteric organisms tenderness is
more and erythema is minimal.
 Other signs of infection like fever , malaise .
Leucocytosis ,tachycardia/ chills may develop.
 Lymph node draining the infected are may also
be involved---to be examined.

23.  All intravenous puncture sites with/ without cannulae along with
all drain sites ---to be seen for any evidence of infection as
thoroughly as wound site examination.
 Nose , throat , ear, chest for infection ---sinusitis , chronic SOM,
atelectasis/ consolidation/ collapse of lung / pleural effusion /
empyema , Pulmonary embolism .
 Abdominal Examination---hepato splenomegaly and tenderness,
abdominal distension , tenderness (localized or general ),rebound
tenderness , free fluid , characters of intestinal sounds , evidence
of peritonitis , intraperitoneal abscess, foreign body , peri nephric
abscess, subdiaphragmatic abscess , pelvic abscess(PR / PV if
needed needling).

24.  Tenderness over renal , bladder indicate UTI.
 Cardiovascular examination----alular disease
(SABE)
 CNS--- Neck stiffness , neck rigidity ,
kerning's sign +vet , photophobia , altered
level of consciousness ----- exclude
meningitis / cerebral infection.

27.  Bacteriological assessment---
 Blood culture , urine culture , wound swab
culture
 sputum/ aspirated pleural fluid / peritoneal fluid
. CSF , if LP done
 Needle aspirate from indurated area/ sp[reading
cellulitis surrounding wound / enlarged lymph
node , culture from cannula and catheter on
removal.
 Stool culture. It should be for identification of
Pathogen and their sensitivity to drugs .

28.  Chest X ray --- PA view --- Pneumonia, etelactasis, pleural
effusion , pleural thickening , metastasis , Lung collapse.
Consolidation , tuberculosis. Chronic bronchitis , cardiomegaly
, pulmonary embolism. Pericardial effusion . Mediastinal mass
etc.
 Flat plate Abdomen --- multiple fluid levels and distended
intestinal loops incases of peritonitis., air under diaphragm in
cases of intestinal perforation. displacement of gas filled
intestinal loops by foreign body, pelvic abscess/ free fluid in
peritoneal cavity.

29.  USG Whole abdomen and pelvis ----amoebic
liver abscess, spleen and liver enlargement, renal
and peri nephric pathology , pelvic abscess,
hematoma, forgotten lepard /instrument .
Doppler can help in identifying thrombosis.
 CAT & MRI can identify abscess , foreign body ,
hematoma and other lesions .
 ECG and Echocardiography ---- myocardial
infarction , pulmonary embolism , intra cardiac
thrombus , valvular disease .

43.  Infection / pus collection may be located My be ---
- endogenous, exogenous ( nurse / doctor ,
instruments , visitors , aseptica conditions of Hospital )
1. Intracranial --thorough History , CNs examination ,
LP , Brain scan---Cat / MRI with dye or without dye.
2. Above Oral Diaphragm –sinusitis, pharyngitis ,Ch.
SOM , Parotid abscess ,Tonsillitis ---ENT checkup ,
throat swab culture .
3. AboveThoraces -abdominal Diaphragm—cardio –
respiratory system—History taking , Chest
examination , X ray chest , sputum examination,
culture , ECG and echocardiogram.

44. 4. Above Pelvic diaphragm --- Symptoms and signs on
abdominal ,pelvic , PR , p v examination .Wound
examination , flat plate X Ray in standing position ,
CBC , wound swab culture, USG,TVS , Urine
examination and culture , Blood culture , catheter /
drain / canola site examination , and culture .
5. In between Pelvic and perineal diaphragm ----
local symptoms of deep seated pain in pelvis and
perineum ---local examination --- pelvic and Perineal
USG.
6. other sites--- gluteal region , Calf muscles for DVT ,
Epidural / spinal anesthesia site .

47.  It is directed at the cause .
 General Measures---Replacement of fluid loss ,
maintain input out put , electrolytes, nutrition , avoid
development of acidosis, control fever below 1ooF by
antipyretics( paracetamol / N-SAIDs and Aspirin ) ,
cold sponging.
 In patient to have an infection , examination to
localize the site and source of infection , culture for
identification of offending pathogens / their
sensitivity to antibiotics --- and appropriate therapy in
optimal doses is must.
 Surgical intervention may be required in the form of
wound debridement , excision of infected wound or
diseased organ to eliminate the constant source of
infection and drainage of pus collected at any site .

51.  Exploratory Laparotomy when intra peritoneal lesion
is suspected .
 Septic pelvicThrombophlebitis may develop 2-4 days
postoperatively. Clinical signs may be unreliable ; can
best be confirmed by Doppler USG / venography .
Immediate heparinization and broad spectrum
antibiotic therapy should be started.
 Patient with septic shock need fluid resuscitation ,
inotopes , vasoactive drugs are needed to address
impending myocardial depression . Mechanical
Ventilation with high saturated oxygenation in ICU
will be needed.

52.  Careful temperature recording and pulse
monitoring will help in early detection of the
fever.
 Thorough review of each individual- right from
the history, pre-op, intra-op, post-op clinical
examination and relevant investigations will
help to clinch the diagnosis.
 Appropriate conservative/ operative
management should be started as early as
possible and if needed, second opinion from
fellow colleagues- physician, surgeon and
anesthetist, microbiologist should be sought.