Surgical site infections - SSI, Study Guides, Projects, Research of Medical Sciences

Download Surgical site infections - SSI and more Study Guides, Projects, Research Medical Sciences in PDF only on Docsity! Surgical infections Acute Abscess * Definition: A localized suppurative inflammation. * Aetiology: A) Predisposing factors: Senility, debility, malignancy, poor general resistance, DM, lack of cleanliness, anaemia, immune deficiency, AIDS & corticosteroid ,chemotherapy or immune suppressive drug. B) Route of infection: 1. Direct spread through a wound , ulcer or natural passage as lactiferous ducts. 2. Local spread from an adjacent septic focus. 3. Blood spread from a septic focus — bacteraemia or pyaemia > e.g. pyaemic liver or lung abscesses 4. Lymphatic Spread to the regional L.Ns. C) Organism: e Usually staphococci that secrete coagulase enzyme. e Less commonly streptococci , gonococci, pneumococci, meningococci , E. coli and B. proteus. * Pathology: The abscess formed of 3 zones, A) Central zone: There is coagulative necrosis — liquefaction by the enzymes released from dead leucocytes — pus which is formed of necrotic tissue, inflammatory exudate, dead & living organism and dead leucocytes. B) Intermediate zone: Formed of granulation tissue forms a protective layer against spread of bacteria and their toxins . C) Peripheral zone of acute inflammation. Surgical Infections * Fate and Complications: T) Resolution: If the general resistance is good and treatment is early and efficient. II) Pointing and rupture is the commonest sequel. The pus tracks along the plane of least resistance until it points on the skin, m.m. or serous surface where it ruptures . III) Spread of infection : 1- Generally — bacteraemia, septicaemia or pyaemia. 2- Locally —> celulitis, lymphangitis and lymphadenitis 3- Cavernous sinus thrombosis if infection affect dangerous area of the face . IV) Chronicity due to inadequate drainage and treatment. V) Antibioma: If pus is formed and not drained but proper antibiotics are given — subside of inflammation and pus become sterile but never absorbed — lump called antibioma. * Clinical Picture: I) Before suppuration: a) General: Fever, anorexia , headache, malaise (FAHM) and tachycardia . b) Local: 1- Abscess start as a painful ill-defined indurated swelling. 2- Pain which is dull aching (due to compression of nerves), tenderness , increases on pressure , dependency & movement and relieved by elevation of the part. 3- Hotness and redness due to hyperaemia. 4- Oedema. 5- Loss of function. Surgical Infections e Packing by gauze or rubber drain protrucing from the abscess cavity for haemostasis and drainage. Remove packing material and repack the abscess every 1 to 2 days until the abscess cavity has resolved and packing materials can no longer be inserted into the abscess. e Later on dressing without packing until complete healing. e Post-operative antibiotics for immunocompromise patient or sever infection . * Acute Abscess * Hilton’s Method Surgical Infections Hilton's methods b) Ultrasound or CT scan guided aspiration for deep abscess as intra-peritoneal abscess . IIT) If chronicity occur: 1. Thin walled abscess > incision and drainage. 2. Thick walled abscess > excision. * NB: e No incision and drainage in amoebic liver, brain , lung and cold abscesses. e Fluctuation is very late and never waited in the breast, prostate, parotid, perineum, perianal, hand and Ludwigs angina. Carbuncle * Definition: A localized infective gangrene of subcutaneous tissues. * Aetiology: 1. Predisposing factors: (As acute abscess) D.M is the most important. 2. Organism: Staphylococcus aureus which has potent necrotoxins. Surgical Infections * Pathology: e Sites: Hairy area e.g. nape of neck (commonest site), back & face. e Infection starting in a hair follicles then it spreads to the underlying fatty subcutaneous tissue with necrosis and thrombosis of blood vessels — infective gangrene of subcutaneous tissue. e The sloughs are adherent and separates slowly. wr . Furuncle * Fate and complications: 1- Spread of infection : (as acute abscess) 2- Sloughs separate leaving an infected ulcer . Surgical Infections Cellulitis Erysipelas Suppurative hidradenitis Necrotizing fasciitis & Fournier’s gangrene 10 Surgical Infections Surgical Site Infections (Postoperative Wound infection) * Definition : Infections of tissues , organs or spaces during or after surgical procedure . * Aetiology: I) Predisposing factors: a) General factors: (As acute abscess) b) Local Factors: 1- Poor blood supply e.g. suture under tension. 2- Poor surgical technique: rough manipulation of tissues, excessive use of diathermy, improper haemostasis & wound haematoma. 3- Presence of foreign body. 4- Operations for peritonitis, operations on unprepared colon or urinary tract. 5- Poor sterilization in the operating theatre. II) Organisms: 1- Endogenous organisms: The organisms are derived from the microflora of the patient eg. from skin (Staph. & Strept), G.I.T. (E. coli, Pseudomonas pyocyanea & Clostriduim Welchii), urinary tract (B. proteus) & respiratory tract (Klebsiella group). 2- Exogenous organisms: The organisms are derived from the external environment (surgical team, instruments, dressings or other patients). IIT) Route of infection: usually direct introduction of infection. * Pathology: e Surgical site infections are classified into : 11 Surgical Infections 1) Incisional which may be : " Superficial : limited to skin and subcutaneous tissues . = Deep : Involving musculoaponeurotic layers . 2) Organs. 3) Spaces as subphrenic , iliac or pelvic abscess . Skin . Superficial Incisional ssl Subcutaneous Tissue Deep Incisional ssl Deep Soft Tissue (fascia & muscle) Organ/Space Ssl Organ/Space e There are 4 types of surgical wounds : 1) Clean: ( class I) = Elective surgery and GIT, urinary & respiratory tracts are not entered . = No contamination with organisms e.g. thyroidectomy. 12 Surgical Infections * D.D: Other causes of postoperative fever (e.g. D.V.T & chest infections) & other causes of wound swelling (eg. haematoma & incisional hernia). * Investigations: 1. Blood picture: usually show leucocytosis but in severe infections (eg. gas gangrene) there is leucopenia. 2. Bacteriological examination with culture & sensetivity of the discharge (no antibiotics 3 days before the sample is taken). 3. Blood culture is essential in serious infections. Usually 3 blood samples are taken over 24 hours. 4. For deep infections: plain X-ray, ultrasonography, C.T scan & radionuclide scan may be needed. * Treatment: I) Prophylaxis: 1. Avoid any predisposing factors (mention them). 2. Prophylactic antibiotics are indicated for clean contaminated or contaminated wounds. They are given preoperative, operative & postoperative. 3. Heavily contaminated wounds should be left opened with delayed primary suture on the 5‘ postoperative day when there is no infection. 4. Correct any source of hospital infection. II) Curative: 1. Drainage of pus by removing stitches & open the wound. 2. Antibiotics guided by culture & sensitivity. 15 Surgical Infections Hand Infections (General Principles) * Incidence: More in manual workers & house wives. * Aetiology: 1. Predisposing factors: Trauma, wounds or punctures 2. Route of infection: usually direct spread of infection or less commonly spread from the surrounding. 3. Organism: Usually staph. aureus (90%). * Pathology: e The condition starts by cellulitis which is followed by resolution or suppuration. e Sloughing and necrosis may result from bacterial toxins or pressure necrosis from tense oedema in closed space with increase pressure . * Classification: 1, Cutaneous & S.C infections: e Paronychia e Pulp space infection e Web space infection 2- Fascial spaces infections: e Thenar space e Hypothenar space e Midpalmar space e Parona space. 3- Synovial sheath: e Digital tenosynovitis e Ulnar and radial bursitis 16 Surgical Infections 4. Bone & joint infections. * Complications: (As acute abscess) * Clinical picture: A) Before suppuration: (as acute abscess). B) After suppuration: (as acute abscess): 1- History of the cause e.g. puncture wound . 2- Pain, tenderness & swelling (pain increases by dependency or during sleep). The site of maximum pain & tenderness is usually diagnostic. 2. There is diffuse oedema, maximum on the dorsum of hand (loose dorsal skin). 3. The characteristic features for the commonest hand infection (mention in short) * Investigations: (as acute abscess) * Treatment: A) Before suppuration: 1- General: Antibiotics against sraph. aureus (flucloxacillin, amoxycillin, erythromycin & cephalosporins) & analgesics. 17 Surgical Infections 7- Soft drains are preferred & dressing. 8- Put the hand in the position of function (the fingers are approximated from the thumb as if holding something). 9- Postoperative physiotherapy to avoid stiffness. * Position of * Position of rest function Fig. 2.42: Cobar sk abscess Acute Paronychia * Definition: Acute Infection of the nail fold. * Incidence: The commonest hand infection. * Aetiology: Trimming skin tags or manicurist unsterile instruments. * Clinical picture: Pain, tenderness & swelling over the nail fold, max. at the angle. 20 Surgical Infections * Treatment: (as usual) + e when pus is formed (throbbing pain), local ring anaesthesia without adrenaline at the root of the finger and drainage by one of the followings : 1- A fine tipped scalpel to raise the nail fold & to incise the skin cap through which pus points 2- Oblique incision or excision of a triangle of skin at the angle of the nail fold. 3- If pus present under the nail > excise the related part of the nail. 4- If floating nail > the nail is dead and it is removed to drain infection. Acute Paronychia 21 Surgical Infections Distended * Purulent paronychia drainage Treatment of Acute Paronychia Pulp Space Infection (Felon infection) Gioss section @ 2004 RENEE L. CANNON Fibrous septa” * Anatomy: e It is the subcutaneous space in front of the terminal phalanx. e It is a closed space separated from the middle phalanx by the inter-phalangeal crease & shut on both sides & distally by a septum extend from skin to periosteum. 22 Surgical Infections engitudinal paramedian = OK: fishiouth = net recommended parallel throuat-and through; not ree lorigitudinal lateral - 04 Treatment of pulp space infection Nail blade Dorsal incision —J flexor Digital a. Pulp space tendon Web space Infection * Anatomy: e There are 3 web spaces, each one of them is wedge in shape with a base at the free edge of the web and an apex between the 2 related metacarpo-phalangeal joints. e It is bounded on both sides by the proximal phalanx and both anteriorly and posteriorly by the skin of the web. e Each web space is continuous distally with related 2 proximal volar spaces ( space in front of proximal phalanx). e Each space contain fat and a lumbrical muscle. e Along the lumbrical muscles infection may spread to the mid- palmar space or thenar space. 25 Surgical Infections * Aetiology: (as general) * Complications: Spread of infections along lumbricals to mid-palmar space & proximal volar spaces. * Clinical Picture: Pain, tenderness & swelling over the web and opposing sides of the related 2 fingers with separation of the 2 adjacent fingers. Figure 4: Cystic swelling over the right pel * Treatment: (as usual) e A dorsal longitudinal incision over the most tender point in the web then Hilton's method. 26 Surgical Infections Midpalmar Space Infection * Anatomy of fascial spaces of the hand : eThe plam of the hand is divided into 3 fascial spaces by: 1. Medial fibrous spetum extending from the medial border of palmar aponeurosis to the 5 metacarpal bone. 2. Lateral fibrous septum extending from the lateral border of plamar aponeurosis to the 3 metacorpal bone. eThese 3 facial spaces are: 1. Hypothenar space medially which contains hypothenar muscles. 2. Thenar space laterally which contains thenar muscles. 3. Mid-palmar space in between the previous 2 spaces. 27 Surgical Infections Hypotnenar Space Infection * Aetiology : puncture wound in the hypothenar eminence . * Clinical Picture: Localized pain, tenderness, hotness, redness and swelling in the hypothenar eminence causing accentuation of the concavity of the hand. * Treatment: A longitudinal incision in the skin only along the medial border of 5th metacarpal bone followed by Hilton's method. Thenar Space Infection * Aetiology : puncture wound in the thenar eminence . * Clinical Picture: Pain, tender, red, hot, swelling with ballooning of thenar eminence and accentuation of the concavity of the hand. * Treatment: e Curved incision along lat. border of 1st dorsal interosseous muscle then introduce a closed sinus forceps along the anterior surface of adductor pollices muscle followed by Hilton's method. 30 Surgical Infections e Incision along the lateral border of the dorsum of the 2nd metacarpal bone followed by Hilton's method. * Alternative incisions for thenar space infection. Ml tf an Parona Space Infection * Anatomy: It is bounded posteriorly by pronator quadratus & anteriorly by ulnar and radial bursae. It communicates with mid- palmar space. 31 Surgical Infections Radius Ulna Pronator Quadratus Space of Parona Flexor Pollicus Longus Ulna Bursa Flexor Carpi Radialis 8, Flexor digitorum profundus 9. Median Nerve 10. Flexor carpi Ulnaris PoP wn no * Aetiology : Usually spread of infection from midpalmar space , ulnar or radial bursitis . * Clinical Picture: Pain, tender, red, hot swelling in the distal part of front of forearm. * Treatment: Drainage along the ulnar side of forearm deep to the flexor tendons & ulnar nerve & artery. 32 Surgical Infections * Treatment: e Through a transverse incision in the distal palmar crease over the proximal cul-de- sac, then introduce a fine catheter and irrigate with antibiotic. In severe cases a counter incision can be done on the distal cul de sac. Incisions for Hand infection Acute Tenosynovitis Of Little Finger and Ulnar Bursitis * Definition: It is a tenosynovitis of the commom flexor synovial sheath with involvement of the synovial sheath of the little finger. * Aetiology: Usually due deep puncture wound. * Clinical Picture: 1- Swelling & oedma of the whole hand, especially the dorsum. 2- Pain & Tenderness: Over the ulnar bursa and the little finger. Maximum pain is present over the kanavel's point (point of meeting 35 Surgical Infections between the proximal palmar crease with the lateral border of hypothenar eminence). 4-There is limitation of movements of the medial 4 fingers with slight semiflexion. * Treatment: e Longitudinal incision along the lateral border of hypothenar eminence. e If extension of infection occur to the forearm > another incision is added along the anterior surface of ulna. Digital — Sheaths yn. Radial Bursa 36 Surgical Infections Acute tenosynovitis Of thumb and radial bursitis * Definition: It is a tenosynovitis of the flexor synovial sheath of the thumb . * Aetiology: Usually due deep puncture wound in the thumb. * Clinical Picture: 1. Pain, tenderness & swelling of the thumb, thenar eminence extending to the distal part of forearm. 2. Limitation of movement & semiflexed thumb. * Treatment: e A longitudinal incision on the medial border of the thenar eminence stopping 2cm distal to the distal crease of the wrist to avoid injury of the motor branch of median nerve. e If extension of infection occur to the forearm: Longitudinal incision in front of radius along the medial side of flexor carpi radialis. » * Incision for drainage of radial bursa. 37