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General Surgery

Cardiovascular Effects of Sevoflurane, Halothane, and Isoflurane

  • Sevoflurane:
    • Maintains cardiac index and heart rate effectively.

    • Exhibits less hypotensive and negative inotropic effects compared to halothane.

    • Cardiac output is greater than that observed with halothane.

    • Recovery from sevoflurane anesthesia is smooth and comparable to isoflurane, with a shorter time to standing than halothane.

  • Halothane:
    • Causes significant decreases in mean arterial pressure, ejection fraction, and cardiac index.

    • Heart rate remains at baseline levels, but overall cardiovascular function is depressed.

    • Recovery from halothane is less favorable compared to sevoflurane and isoflurane.

  • Isoflurane:
    • Preserves cardiac index and ejection fraction better than halothane.

    • Increases heart rate while having less suppression of mean arterial pressure compared to halothane.

    • Cardiac output during isoflurane anesthesia is similar to that of sevoflurane, indicating a favorable cardiovascular profile.

An ulcer is a break in the continuity of the skin or the mucous membrane.

Mode of onset:  Traumatic ulcers heal when the traumatic agent is removed., If it persists it becomes chronic as in the case of dental ulcer of the tongue. Ulcers may develop spontaneously as in the case of gumma (syphilitic ulcer). It may develop with varicose veins called varicose ulcer, which develops in the lower third of the leg.

Sometimes a malignant ulcer develops in a scar called Marjolin’s ulcer. Special features are:

 No pain - as there are no nerves. It does not spread - as there is scar tissue. No metastases - as there are no lymphatics Treatment:- Wide excision.

Classification of Ulcer

A) Pathologically

I. Non-specific ulcers:

a. Due to infected wound after trauma, that is physical or chemical agents.

b. Due to local infection example dental ulcer, pressure sore

 Specific ulcers: Caused by specific infection

a. Syphilitic ulcers (Hunterian chancre)

b. Tubercular  ulcers, actinomycosis

Trophic ulcer:- Caused by two factors:

Diminished nutrition due to inadequate blood supply to the tissues

Eg. Ulcers in Buerger’s Disease, Artherosclerosis

b. Diminished or absence of sensation of the skin leading to perforating ulcer of the foot

iv. Malignant ulcer: Due to squamous cell carcinoma, rodent ulcers and melanoma.

B) Clinical classification of ulcers

1. Acute Ulcer:  The edge is inflamed oedematous and painful with slough in the floor and n o granulation tissue. Profuse purulent Discgarge seen

2. Healing ulcers: edge sloping with bluish margin The floor is covered with a red, healthy granulation tissue.

3. Chronic or callous ulcer (non- healing) There is no tendency to heal by itself, the base is jndurated  unhealthy granulation tissue is present in the floor The edge is rounded and thickened.

Chronic ulcer occur due to:

Chronic infection , Defective circulation , Foreign body, Persistent local oedema , Malignancy , Diabetes , Malnutrition (loss of proteins), Gout

Specific Ulcers

Tubeculous Ulcer

Edge Undermined, floor contains granulation tissue a watery discharge is present. Caseous material is found in the floor of the ulcer. It usually occurs in tubercular lymphadenitis in the neck, axilla or groin.

Syphilitic Ulcer

a) Huntarian Chancre or  primary sore or hard chancre: usuaIly occurs over the genitalia especially on penis. Occurs in the primary stage of syphilis Ulcer is round or oval, it is hard,indurated, elevated and painless It feels like a button, discharges serum containing spirochetes (cork screw) which is highly infective.

b) In the Secondary stage mucous patches and condylomata occurs The ulcers are shallow white patches, of sodden thickness which occur in the mouth and tongue. Condyloma are hypertrophied epithelium with serous discharge occurring in mucocutaneous junction around the anus. The regional lymphnod (inguinal transverse chain) are enlarged.

c) In tertiary stage of syphilis gummatous ulcers occur They have a punched  out edge and wash Ieather floor. They occur on the subcutaneous bones like sternum and tibia. They are painless and refuse to heal.

Soft Sore (chanchroid)

They are painful muitiple ulcers, with copious discharge. They are caused by Bacillus Ducrey  lncubation time is 3 to 4 days. located on glans penis and prepuce is due to venereal infection. They are associated with enlarged called bilateral inguinal lymphnodes

Tropical ulcer:

a) Oriental Sore - due to L. Tropica (lieshmaniasis)

b) Ulcers and sinuses are due to guinea worm abscess

c) Histoplasmosis with multiple ulcers on the tibia.

d) Chronic ulcers due to yaws

e) Amoebic ulcers occur in colon_and rectum , flask shaped ulcers , undermined edge , caused by  Entamoeba Histolytica

Varicose Ulcer:

Associated with varicose veins. Occurs on the inner aspect of the lower third of leg , chronic ulcer The surrounding area is pigmented and eczema is present. The sore is longitudinally oval It does not penetrate the deep fascia and is painless The base is adherent to the periosteum of the tibia

Rodent ulcer

Usually Occurs on the face above a line joining the lobule of the ear to the angle of the mouth. Usually occurs at the inner canthous of the eye . Edge is raised and rolled, Erodes the deeper structures and the bone, the lyrnph nodes are not involved.

Treatment: If small wide excision is done with skin grafting, If large, radiotherapy is given.

Malignant Ulcer

Occurs due to chronic irritation as in the case of malignant ulcer of the tongue. The edge is everted. The floor is covered with slough and tumor tissue The regional lymph nodes are hard.

Initially mobile later becomes hard

Treatment: Wide excision is done.

Marjolin ulcer: Malignant Ulcer occurring on scar of Burns

Advanced Trauma Life Support (ATLS)

Introduction

Trauma is a leading cause of death, particularly in the first four decades of life, and ranks as the third most common cause of death overall. The Advanced Trauma Life Support (ATLS) program was developed to provide a systematic approach to the management of trauma patients, ensuring that life-threatening conditions are identified and treated promptly.

Mechanisms of Injury

In trauma, injuries can be classified based on their mechanisms:

Overt Mechanisms

  1. Penetrating Trauma: Injuries caused by objects that penetrate the skin and underlying tissues.
  2. Blunt Trauma: Injuries resulting from impact without penetration, such as collisions or falls.
  3. Thermal Trauma: Injuries caused by heat, including burns.
  4. Blast Injury: Injuries resulting from explosions, which can cause a combination of blunt and penetrating injuries.

Covert Mechanisms

  1. Blunt Trauma: Often results in internal injuries that may not be immediately apparent.
  2. Penetrating Trauma: Can include knife wounds and other sharp objects.
  3. Penetrating Knife: Specific injuries from stabbing.
  4. Gunshot Injury: Injuries caused by firearms, which can have extensive internal damage.

The track of penetrating injuries can often be identified by the anatomy involved, helping to determine which organs may be injured.

Steps in ATLS

The ATLS protocol consists of a systematic approach to trauma management, divided into two main surveys:

1. Primary Survey

  • Objective: Identify and treat life-threatening conditions.
  • Components:
    • A - Airway: Ensure the airway is patent. In patients with a Glasgow Coma Scale (GCS) of 8 or less, immediate intubation is necessary. Maintain cervical spine stability.
    • B - Breathing: Assess ventilation and oxygenation. Administer high-flow oxygen via a reservoir mask. Identify and treat conditions such as tension pneumothorax, flail chest, massive hemothorax, and open pneumothorax.
    • C - Circulation: Evaluate circulation based on:
      • Conscious level (indicates cerebral perfusion)
      • Skin color
      • Rapid, thready pulse (more reliable than blood pressure)
    • D - Disability: Assess neurological status using the Glasgow Coma Scale (GCS).
    • E - Exposure: Fully expose the patient to assess for injuries on the front and back.

2. Secondary Survey

  • Objective: Conduct a thorough head-to-toe examination to identify all injuries.
  • Components:
    • AMPLE: A mnemonic to gather important patient history:
      • A - Allergy: Any known allergies.
      • M - Medications: Current medications the patient is taking.
      • P - Past Medical History: Relevant medical history.
      • L - Last Meal: When the patient last ate.
      • E - Events of Incident: Details about the mechanism of injury.

Triage

Triage is the process of sorting patients based on the severity of their condition. The term "triage" comes from the French word meaning "to sort." In trauma settings, patients are categorized using a color-coded system:

  • Red: First priority (critical patients, e.g., tension pneumothorax).
  • Yellow: Second priority (urgent cases, e.g., pelvic fracture).
  • Green: Third priority (minor injuries, e.g., simple fracture).
  • Black: Zero priority (patients who are dead or unsalvageable).

Blunt Trauma

  • Common Causes: The most frequent cause of blunt trauma is road traffic accidents.
  • Seat Belt Use: Wearing seat belts significantly reduces mortality rates:
    • Front row occupants: 45% reduction in death rate.
    • Rear seat belt use: 80% reduction in death rate for front seat occupants.
  • Seat Belt Injuries: Marks on the thorax indicate a fourfold increase in thoracic injuries, while abdominal marks indicate a threefold increase in abdominal injuries.

Radiographs in Trauma

Key radiographic views to obtain in trauma cases include:

  1. Lateral cervical spine
  2. Anteroposterior chest
  3. Anteroposterior pelvis

Tracheostomy

Tracheostomy is a surgical procedure that involves creating an opening in the trachea (windpipe) to facilitate breathing. This procedure is typically performed when there is a need for prolonged airway access, especially in cases where the upper airway is obstructed or compromised. The incision is usually made between the 2nd and 4th tracheal rings, as entry through the 1st ring can lead to complications such as tracheal stenosis.

Indications

Tracheostomy may be indicated in various clinical scenarios, including:

  1. Acute Upper Airway Obstruction: Conditions such as severe allergic reactions, infections (e.g., epiglottitis), or trauma that obstruct the airway.
  2. Major Surgery: Procedures involving the mouth, pharynx, or larynx that may compromise the airway.
  3. Prolonged Mechanical Ventilation: Patients requiring artificial ventilation for an extended period, such as those with respiratory failure.
  4. Unconscious Patients: Situations involving head injuries, tetanus, or bulbar poliomyelitis where airway protection is necessary.

Procedure

Technique

  • Incision: A horizontal incision is made in the skin over the trachea, typically between the 2nd and 4th tracheal rings.
  • Dissection: The subcutaneous tissue and muscles are dissected to expose the trachea.
  • Tracheal Entry: An incision is made in the trachea, and a tracheostomy tube is inserted to maintain the airway.

Complications of Tracheostomy

Tracheostomy can be associated with several complications, which can be categorized into intraoperative, early postoperative, and late postoperative complications.

1. Intraoperative Complications

  • Hemorrhage: Bleeding can occur during the procedure, particularly if major blood vessels are inadvertently injured.
  • Injury to Paratracheal Structures:
    • Carotid Artery: Injury can lead to significant hemorrhage and potential airway compromise.
    • Recurrent Laryngeal Nerve: Damage can result in vocal cord paralysis and hoarseness.
    • Esophagus: Injury can lead to tracheoesophageal fistula formation.
    • Trachea: Improper technique can cause tracheal injury.

2. Early Postoperative Complications

  • Apnea: Temporary cessation of breathing may occur, especially in patients with pre-existing respiratory issues.
  • Hemorrhage: Postoperative bleeding can occur, requiring surgical intervention.
  • Subcutaneous Emphysema: Air can escape into the subcutaneous tissue, leading to swelling and discomfort.
  • Pneumomediastinum and Pneumothorax: Air can enter the mediastinum or pleural space, leading to respiratory distress.
  • Infection: Risk of infection at the incision site or within the tracheostomy tube.

3. Late Postoperative Complications

  • Difficult Decannulation: Challenges in removing the tracheostomy tube due to airway swelling or other factors.
  • Tracheocutaneous Fistula: An abnormal connection between the trachea and the skin, which may require surgical repair.
  • Tracheoesophageal Fistula: An abnormal connection between the trachea and esophagus, leading to aspiration and feeding difficulties.
  • Tracheoinnominate Arterial Fistula: A rare but life-threatening complication where the trachea erodes into the innominate artery, resulting in severe hemorrhage.
  • Tracheal Stenosis: Narrowing of the trachea due to scar tissue formation, which can lead to breathing difficulties.

SHOCK

Shock  is  defined  as  a  pathological  state  causing  inadequate  oxygen  delivery  to  the peripheral tissues and resulting in lactic acidosis, cellular hypoxia and disruption of normal metabolic condition.

CLASSIFICATION

Shock is generally classified into three major categories:

1.    Hypovolemic shock

2.    Cardiogenic shock

3.    Distributive shock

Distributive shock is further subdivided into three subgroups:

a.    Septic shock

b.    Neurogenic shock

c.    Anaphylactic shock

Hypovolemic  shock  is  present  when  marked  reduction  in  oxygen  delivery results from diminished cardiac output secondary to inadequate vascular volume. In general, it results from loss of fluid from circulation, either directly or indirectly.
e.g.    ?    Hemorrhage
    •    Loss of plasma due to burns
    •    Loss of water and electrolytes in diarrhea
    •    Third space loss (Internal fluid shift into inflammatory exudates in
        the peritoneum, such as in pancreatitis.)

Cardiogenic shock is present when there is severe reduction in oxygen delivery secondary to impaired cardiac function. Usually it is due to myocardial infarction or pericardial tamponade.

Septic Shock (vasogenic shock) develops as a result of the systemic effect of infection. It is the result of a septicemia with endotoxin and exotoxin release by gram-negative and gram-positive bacteria. Despite normal or increased cardiac output and oxygen delivery, cellular oxygen consumption is less than normal due to impaired extraction as a result of impaired metabolism.

Neurogenic shock results primarily from the disruption of the sympathetic nervous system which may be due to pain or loss of sympathetic tone, as in spinal cord injuries.

PATHO PHYSIOLOGY OF SHOCK

Shock stimulates a physiologic response. This circulatory response to hypotension is to conserve perfusion to the vital organs (heart and brain) at the expense of other tissues. Progressive vasoconstriction of skin, splanchnic and renal vessels leads to renal cortical necrosis and acute renal failure. If not corrected in time, shock leads to organ failure and sets up a vicious circle with hypoxia and acidosis.

CLINICAL FEATURES

The clinical presentation varies according to the cause. But in general patients with hypotension and reduced tissue perfusion presents with:
•    Tachycardia
•    Feeble pulse
•    Narrow pulse pressure
•    Cold extremities (except septic shock)
•    Sweating, anxiety
•    Breathlessness / Hyperventilation
•    Confusion leading to unconscious state

PATHO PHYSIOLOGY OF SHOCK

Shock stimulates a physiologic response. This circulatory response to hypotension is to conserve perfusion to the vital organs (heart and brain) at the expense of other tissues. Progressive vasoconstriction of skin, splanchnic and renal vessels leads to renal cortical necrosis and acute renal failure. If not corrected in time, shock leads to organ failure and sets up a vicious circle with hypoxia and acidosis.

CLINICAL FEATURES

The clinical presentation varies according to the cause. But in general patients with hypotension and reduced tissue perfusion presents with:
•    Tachycardia
•    Feeble pulse
•    Narrow pulse pressure
•    Cold extremities (except septic shock)
•    Sweating, anxiety
•    Breathlessness / Hyperventilation
•    Confusion leading to unconscious state

Ludwig's Angina

Ludwig's angina is a serious, potentially life-threatening cellulitis or connective tissue infection of the submandibular space. It typically arises from infections of the teeth, particularly the second or third molars, and can lead to airway obstruction due to swelling. This condition is named after the German physician Wilhelm Friedrich von Ludwig, who first described it in the 19th century.

Etiology

  • Common Causes:

    • Dental infections (especially from the lower molars)
    • Infections from the floor of the mouth
    • Trauma to the submandibular area
    • Occasionally, infections can arise from other sources, such as the oropharynx or skin.
  • Microbial Agents:

    • Mixed flora, including both aerobic and anaerobic bacteria.
    • Common organisms include Streptococcus, Staphylococcus, and Bacteroides species.

Pathophysiology

  • The infection typically begins in the submandibular space and can spread rapidly due to the loose connective tissue in this area.
  • The swelling can lead to displacement of the tongue and can obstruct the airway, making it a medical emergency.

Clinical Presentation

  • Symptoms:

    • Swelling of the submandibular area, which may be bilateral
    • "Brawny induration" (firm, non-fluctuant swelling)
    • Pain and tenderness in the submandibular region
    • Difficulty swallowing (dysphagia) and speaking (dysarthria)
    • Fever and malaise
    • Possible elevation of the floor of the mouth and displacement of the tongue
  • Signs:

    • Swelling may extend to the neck and may cause "bull neck" appearance.
    • Trismus (limited mouth opening) may be present.
    • Respiratory distress due to airway compromise.

Diagnosis

  • Clinical Evaluation: Diagnosis is primarily clinical based on history and physical examination.
  • Imaging:
    • CT scan of the neck may be used to assess the extent of the infection and to rule out other conditions.
    • X-rays may show air in the soft tissues if there is a necrotizing infection.

Management

Initial Management

  • Airway Management:
    • Ensure the airway is patent; this may require intubation or tracheostomy in severe cases.

Medical Treatment

  • Antibiotics:
    • Broad-spectrum intravenous antibiotics are initiated to cover both aerobic and anaerobic bacteria. Common regimens may include:
      • Ampicillin-sulbactam
      • Clindamycin
      • Metronidazole combined with a penicillin derivative

Surgical Intervention

  • Drainage:
    • Surgical drainage may be necessary if there is an abscess formation or significant swelling.
    • Incisions are typically made in the submandibular area to allow for drainage of pus and to relieve pressure.

Complications

  • Airway Obstruction: The most critical complication, requiring immediate intervention.
  • Sepsis: Can occur if the infection spreads systemically.
  • Necrotizing fasciitis: Rare but serious complication that may require extensive surgical intervention.
  • Thrombosis of the internal jugular vein: Can occur due to the spread of infection.

Prognosis

  • With prompt diagnosis and treatment, the prognosis is generally good. However, delays in management can lead to significant morbidity and mortality due to airway compromise and systemic infection.

Inflammation is the respone of the body to an irritant.

Stages of Inflammation

1. General: Temperature Raised. In severe cases bacteremia or septicemia ,rigors may occur.

2. Local: classical signs of inflammation are due to hyperemia and inflammation exudate

i) Heat:  inflammed area feels warmer than the surrounding tissues.

ii) Redness

iii) Tenderness: Due to pressure of exudate on the surrounding nerves  If the exudate is  under tension, e.g. a furuncle (boil) of the ear, pain is severe.

iv) swelling

v) Loss of function.

The termination of Inflammation

This may be by:1. Resolution 2. Suppuration 3. Ulceration 4. Ganangren s. Fibrosis

Management

i. Increase the patients resistance., Rest,  Relief of pain by analgesics,  Diet: High protein and high calorie diet with vitamins,  Antibiotics,  Prevent further contamination of wound.

Surgical measures

1. Excision: If possible as in appendicectomy.

2. Incision and drainage: If an abscess forms.

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