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General Surgery

Zygomatic Bone Reduction

When performing a reduction of the zygomatic bone, particularly in the context of maxillary arch fractures, several key checkpoints are used to assess the success of the procedure. Here’s a detailed overview of the important checkpoints for both zygomatic bone and zygomatic arch reduction.

Zygomatic Bone Reduction

  1. Alignment at the Sphenozygomatic Suture:

    • While this is considered the best checkpoint for assessing the reduction of the zygomatic bone, it may not always be the most practical or available option in certain clinical scenarios.
  2. Symmetry of the Zygomatic Arch:

    • Importance: This is the second-best checkpoint and serves multiple purposes:
      • Maintains Interzygomatic Distance: Ensures that the distance between the zygomatic bones is preserved, which is crucial for facial symmetry.
      • Maintains Facial Symmetry and Aesthetic Balance: A symmetrical zygomatic arch contributes to the overall aesthetic appearance of the face.
      • Preserves the Dome Effect: The prominence of the zygomatic arch creates a natural contour that is important for facial aesthetics.
  3. Continuity of the Infraorbital Rim:

    • A critical checkpoint indicating that the reduction is complete. The infraorbital rim should show no step-off, indicating proper alignment and continuity.
  4. Continuity at the Frontozygomatic Suture:

    • Ensures that the junction between the frontal bone and the zygomatic bone is intact and properly aligned.
  5. Continuity at the Zygomatic Buttress Region:

    • The zygomatic buttress is an important structural component that provides support and stability to the zygomatic bone.

Zygomatic Arch Reduction

  1. Click Sound:

    • The presence of a click sound during manipulation can indicate proper alignment and reduction of the zygomatic arch.
  2. Symmetry of the Arches:

    • Assessing the symmetry of the zygomatic arches on both sides of the face is crucial for ensuring that the reduction has been successful and that the facial aesthetics are preserved.

Types of Head Injury

1. Extradural Hematoma (EDH)

Overview

  • Demographics: Most common in young male patients.
  • Association: Always associated with skull fractures.
  • Injured Vessel: Middle meningeal artery.
  • Common Site of Injury: Temporal bone at the pterion (the thinnest part of the skull), which overlies the middle meningeal artery.
  • Location of Hematoma: Between the bone and the dura mater.

Other Common Sites

  1. Frontal fossa
  2. Posterior fossa
  3. May occur following disruption of major dural venous sinus.

Classical Presentation

  • Initial Injury: Followed by a lucid interval where the patient may only complain of a headache.
  • Deterioration: After minutes to hours, rapid deterioration occurs, leading to:
    • Contralateral hemiparesis
    • Reduced consciousness level
    • Ipsilateral pupillary dilatation (due to herniation)

Imaging

  • CT Scan: Shows a lentiform (lens-shaped or biconvex) hyperdense lesion between the brain and skull.

Treatment

  • Surgical Intervention: Immediate surgical evacuation via craniotomy.
  • Mortality Rate: Overall mortality is 18% for all cases of EDH, but only 2% for isolated EDH.

2. Acute Subdural Hematoma (ASDH)

Overview

  • Location: Accumulates in the space between the dura and arachnoid.
  • Injury Mechanism: Associated with cortical vessel disruption and brain laceration.
  • Primary Brain Injury: Often associated with primary brain injury.

Presentation

  • Consciousness: Impaired consciousness from the time of impact.

Imaging

  • CT Scan: Appears hyperdense, with hematoma spreading diffusely and having a concavo-convex appearance.

Treatment

  • Surgical Intervention: Evacuation via craniotomy.
  • Mortality Rate: Approximately 40%.

3. Chronic Subdural Hematoma (CSDH)

Overview

  • Demographics: Most common in patients on anticoagulants and antiplatelet agents.
  • History: Often follows a minor head injury weeks to months prior.
  • Pathology: Due to the tear of bridging veins leading to ASDH, which is clinically silent. As the hematoma breaks down, it increases in volume, causing mass effect on the underlying brain.

Clinical Features

  • Symptoms may include:
    • Headache
    • Cognitive decline
    • Focal neurological deficits (FND)
    • Seizures
  • Important to exclude endocrine, hypoxic, and metabolic causes in this group.

Imaging

  • CT Scan Appearance:
    • Acute blood (0–10 days): Hyperdense
    • Subacute blood (10 days to 2 weeks): Isodense
    • Chronic (> 2 weeks): Hypodense

Treatment

  • Surgical Intervention: Bur hole evacuation rather than craniotomy.
  • Anesthesia: Elderly patients can often undergo surgery under local anesthesia, despite comorbidities.

4. Subarachnoid Hemorrhage (SAH)

Overview

  • Causes: Most commonly due to aneurysms for spontaneous SAH, but trauma is the most common cause overall.
  • Management: Conservative treatment is often employed for trauma cases.

5. Cerebral Contusions

Overview

  • Definition: Bruising of the brain tissue due to trauma.
  • Mechanism: Often occurs at the site of impact (coup) and the opposite side (contrecoup).
  • Symptoms: Can range from mild confusion to severe neurological deficits depending on the extent of the injury.

Imaging

  • CT Scan: May show areas of low attenuation (hypodense) or high attenuation (hyperdense) depending on the age of the contusion.

Treatment

  • Management: Depends on the severity and associated injuries; may require surgical intervention if there is significant mass effect.

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.

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

Types of Brain Injury

Brain injuries can be classified into two main categories: primary and secondary injuries. Understanding these types is crucial for effective diagnosis and management.

1. Primary Brain Injury

  • Definition: Primary brain injury occurs at the moment of impact. It results from the initial mechanical forces applied to the brain and can lead to immediate damage.
  • Examples:
    • Contusions: Bruising of brain tissue.
    • Lacerations: Tears in brain tissue.
    • Concussions: A temporary loss of function due to trauma.
    • Diffuse axonal injury: Widespread damage to the brain's white matter.

2. Secondary Brain Injury

  • Definition: Secondary brain injury occurs after the initial impact and is often preventable. It results from a cascade of physiological processes that can exacerbate the initial injury.
  • Principal Causes:
    • Hypoxia: Reduced oxygen supply to the brain, which can worsen brain injury.
    • Hypotension: Low blood pressure can lead to inadequate cerebral perfusion.
    • Raised Intracranial Pressure (ICP): Increased pressure within the skull can compress brain tissue and reduce blood flow.
    • Reduced Cerebral Perfusion Pressure (CPP): Insufficient blood flow to the brain can lead to ischemia.
    • Pyrexia: Elevated body temperature can increase metabolic demands and worsen brain injury.

Glasgow Coma Scale (GCS)

The Glasgow Coma Scale is a clinical tool used to assess a patient's level of consciousness and neurological function. It consists of three components: eye opening, verbal response, and motor response.

Eye Opening (E)

  • Spontaneous: 4
  • To verbal command: 3
  • To pain stimuli: 2
  • No eye opening: 1

Verbal Response (V)

  • Normal, oriented: 5
  • Confused: 4
  • Inappropriate words: 3
  • Sounds only: 2
  • No sounds: 1

Motor Response (M)

  • Obeys commands: 6
  • Localizes to pain: 5
  • Withdrawal flexion: 4
  • Abnormal flexion (decorticate): 3
  • Extension (decerebrate): 2
  • No motor response: 1

Scoring

  • Best Possible Score: 15/15 (fully alert and oriented)
  • Worst Possible Score: 3/15 (deep coma or death)
  • Intubated Cases: For patients who are intubated, the verbal score is recorded as "T."
  • Intubation Indication: Intubation should be performed if the GCS score is less than or equal to 8.

Additional Assessments

Pupil Examination

  • Pupil Reflex: Assess size and light response.
  • Uncal Herniation: In cases of mass effect on the ipsilateral side, partial third nerve dysfunction may be noted, characterized by a larger pupil with sluggish reflex.
  • Hutchinson Pupil: As third nerve compromise increases, the ipsilateral pupil may become fixed and dilated.

Signs of Base of Skull Fracture

  • Raccoon Eyes: Bilateral periorbital hematoma, indicating possible skull base fracture.
  • Battle’s Sign: Bruising over the mastoid process, suggesting a fracture of the temporal bone.
  • CSF Rhinorrhea or Otorrhea: Leakage of cerebrospinal fluid from the nose or ear, indicating a breach in the skull base.
  • Hemotympanum: Blood in the tympanic cavity, often seen with ear bleeding.

Walsham’s Forceps

Walsham’s forceps are specialized surgical instruments used primarily in the manipulation and reduction of fractured nasal fragments. They are particularly useful in the management of nasal fractures, allowing for precise adjustment and stabilization of the bone fragments during the reduction process.

  1. Design:

    • Curved Blades: Walsham’s forceps feature two curved blades—one padded and one unpadded. The curvature of the blades allows for better access and manipulation of the nasal structures.
    • Padded Blade: The padded blade is designed to provide a gentle grip on the external surface of the nasal bone and surrounding tissues, minimizing trauma during manipulation.
    • Unpadded Blade: The unpadded blade is inserted into the nostril and is used to secure the internal aspect of the nasal bone and associated fragments.
  2. Usage:

    • Insertion: The unpadded blade is carefully passed up the nostril to reach the fractured nasal bone and the associated fragment of the frontal process of the maxilla.
    • Securing Fragments: Once in position, the nasal bone and the associated fragment are secured between the padded blade externally and the unpadded blade internally.
    • Manipulation: The surgeon can then manipulate the fragments into their correct anatomical position, ensuring proper alignment and stabilization.
  3. Indications:

    • Walsham’s forceps are indicated for use in cases of nasal fractures, particularly when there is displacement of the nasal bones or associated structures. They are commonly used in both emergency and elective settings for nasal fracture management.
  4. Advantages:

    • Precision: The design of the forceps allows for precise manipulation of the nasal fragments, which is crucial for achieving optimal alignment and aesthetic outcomes.
    • Minimized Trauma: The padded blade helps to reduce trauma to the surrounding soft tissues, which can be a concern during the reduction of nasal fractures.
  5. Postoperative Considerations:

    • After manipulation and reduction of the nasal fragments, appropriate postoperative care is essential to monitor for complications such as swelling, infection, or malunion. Follow-up appointments may be necessary to assess healing and ensure that the nasal structure remains stable.

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

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