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.

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.

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.

1 Cellulitis: a non-suppurative inflammation of subcutaneous tissue, extending along connective tissue planes and across intercellular spaces.

Spreading inflammation in the tissue planes is called cellulitis. There is wide spread swelling, redness and pain without definite localization.

Caused by Streptococcus pyogenes.. If general condition of the patient is undermined, as in diabetes, cellulitis spreads rapidly and leads to Septicemia (infection in the blood).Redness, itching and stiffness is present in the site of inoculation (where the bacteria enter the skin), local Gangrene (death of the tissue) may occur. The appearance of skin creases or wrinkles, indicates resolution (healing).

Treatment

1. Rest , Appropriate antibiotics.

Cellulitis of the neck: Is a complication of wounds tonsillitis or mastoiditis Ludwig’s angina is the term applied to sub-maxillary cellulitis. The two dangers of cervical cellulitis are:

1. Oedema of glottis - with possible asphyxia (respiratory obstructon )

2. Mediastinitis - In ludwig’s angina the floor of the mouth become oedematous. The tongue can be seen displaced, turned upwards by swelling and oedema. The patient is unable to close the mouth owing to oedema of the tongue and the floor of the mouth. This can also CCC when the tongue is bitten by a wasp.

Ludwig’s angina: Ludwig - characterized by a brawny (non pitting) swelling of the sub-mandibular region, corn with inflammatory oedema of the mouth. It is the combined cervical and intrabuccal signs that constitute the characteristic feature of the lesion. The cause of the condition is virulent, usually streptococcal infection of the cellular tissue surrounding the sub-mandibular salivary gland.

Clinical features

 The swollen tongue is pushed towards the palate and forwards through the open mouth, while the cellulitis extends down the neck.

The most dangerous plane, is deep to the deep fascia.

Ludwig’s angina is an infection of closed fascial space and if .untreated, the inflammatory exudate often passes via, the tunnel occupied by stylohyhoid to the submucosa of glottis, in which event the patient is in immediate danger of death from oedema of the glottis.

Treatment

1. antibiotics on Early Diagnosis

2. In cases where the swelling, both cervical and intrabuccal, does not subside rapidly with such treatment, a curved incision, beneath the jaw is made and this decompresses the closed fascial space. The incision is deepened and after displacing the superficial lobe of the sub-mandibular salivary gland, the mylohyoid muscle are divided. This decompresses the closed fascjal space referred to. The wound is lightly sutured and drained. The operation can be conducted with greatest safety under local anaesthesia.

Bacteraemia and  Septicemia

Bacteraemia and septicaemia means the organisms are present in the blood. Clinical features are those of severe infection and shock: , Pyrexia is intermittent , Rigors ,  Jaundice is due to liver damage,  Acute renal failure may occur , Peripheral circulatory failure,  lntravascular coagulation indicates a fatal outcome

 causative focus found and treated surgically .g., Appendicetomy in perforated appendix

2. Blood culture taken

3. Broad spectrum antibiotic is given

4. Blood transfusion is given.

5. Injection hydrocortisone is given.

Pyaemia

Pyaemia is due to infected emboli circulating in blood stream. Pyaemia is characterized by: -

1. Rigors

2. Intermittent fever

3. Formation of abscess in vital organs like heart or brain.

Treatment

1. Is to prevent emboli reaching the blood stream

2. Broad spectrum antibiotic is given.

3. Abscess are incised and drained

If not treated portal pyaemia with multiple abscesses in liver occur, which is a dangerous condition.

Acute Abscess :  An abscess a collection of pus.

Bacteria which cause pus formation is called pyogenic organisms. Bacteria reach the infected area by:

1. Direct route: eg. Penetrating wound

Local extension: From adjacent focus of infection

2 Lymphatics

4. Blood stream

Pyogenic membrane surrounds the abscess and is infiltration with (leukocytes and bacteria.

Pus: Pus contains dead leukocytes and bacteria. It reaches the surface of the body or is discharged into a hollow viscous.

Symptoms: patient feels ill., Throbbing pain is characteristic of suppuration. Pain becomes more severe in the dependent position. E.g. infected finger,

Classical signs

Temperature is elevated , Rigors, inflammation

Fluctuation: Present in the later stages, and reveals the presence of pus. Prevention

1. An abscess can sometimes be aborted by antibiotics in the early stage.,. Rest,  Elevation of the affected part.

Treatment

Is incision and drainage of abscess

Hilton’s method of opening an abscess:

It is used where important anatomical structures like the blood vessels and nerves are preesnt, as in the neck, axilla and groin. The skin and superficial fascia is incised. A sinus forceps is thrust into the abscess  cavity. The blades are opened and the pus is drained. A gloved finger is introduced and loculi are broken. A ribbon gauze is lightly packed and antibiotics are given. This is done under surface anaesthesia i.e., ethyl chloride spray.

Antibioma

 If antibiotic is given the pus in the abscess frequently becomes sterile and a large brawny edematous swelling remains which takes many weeks to resolve.

Treatment: explore the mass with a wide-bore aspirating needle

 Most antibiornas are due to late, inadequate, and ineffective antibiotics.

CANCRUM ORIS

Is an infective gangrene of cheek and lip.

may occur as a complication of kala azar, enteric fever and  children with poor oral hygiene.

The lesion starts as an acute inflammatory patch on oral mucosa which is seen ulcerated.

The affected part of the cheek or the lip gradually becomes gangrenous.

Focal vascular thrombosis and sepesis occur.

When slough separates, a part of the cheek or lip sloughs out to form a buccal fistula with ugly deformity. The adjacent jaw may be infected too.

Various organisms are found - specially Fusiform bacillus and_Borrellia vincenti.

The foetid odour, gangrenous patch of cheek or lip, purulent discharge from the mouth, fever and toxaemia are the characteristic features. The patient is unable to open the mouth properly.

Treatment

1. Antibiotics, multivitamins and repeated mouth washes

2 Neostibamine in kala-azar. Sequestrectomy in chronic osteomyelitis of the mandible.

4. Plastic reconstruction of the lip or cheek for unsightly deformity undertaken.

CARBUNCLE

Is an infective gangrene of the subcutaneous tissue. It is due to staphylococcal aureus infection. It is uncommon before the age of 40. Males are the usual sufferers. Diabetes may be present. It often occurs on the nape of the neck.

Clinical features

Subcutaneous tissue becomes painful and indurated. Ove skin is red. Unless treated promptly, extension will occur and late softening. The skin gives way and thick pus and slough are discharged.

Usually, there is one central large slough, surrounded by smaller areas of necrosis. Infection extends widely and fresh openings appear

Treatment

1. Many carbuncles are aborted, if penicillin is used adequately in the early stage.

2. Local treatment consists of hygroscopic dressings being given ie. magsulph-glycerin dressing Later the carbuncle is excised with a cruciate incision.

3. If the gap is large and when the granulation tissue comes to the surface, skin grafting is done.

Dautrey Procedure

The Dautrey procedure is a surgical intervention aimed at preventing dislocation of the temporomandibular joint (TMJ) by creating a mechanical obstacle that restricts abnormal forward translation of the condylar head. This technique is particularly beneficial for patients who experience recurrent TMJ dislocations or subluxations, especially when conservative management strategies have proven ineffective.

1. Indications:

   • The Dautrey procedure is indicated for patients with a history of recurrent TMJ dislocations. It is particularly useful when conservative treatments, such as physical therapy or splint therapy, have failed to provide adequate stabilization of the joint.

2. Surgical Technique:

   • Osteotomy of the Zygomatic Arch: The procedure begins with an osteotomy, which involves surgically cutting the zygomatic arch, the bony structure that forms the prominence of the cheek.
   • Depressing the Zygomatic Arch: After the osteotomy, the zygomatic arch is depressed in front of the condylar head. This depression creates a physical barrier that acts as an obstacle to the forward movement of the condylar head during jaw opening or excessive movement.
   • Stabilization: The newly positioned zygomatic arch limits the range of motion of the condylar head, thereby reducing the risk of dislocation during functional activities such as chewing or speaking.

3. Mechanism of Action:

   • By altering the position of the zygomatic arch, the Dautrey procedure effectively changes the biomechanics of the TMJ. The new position of the zygomatic arch prevents the condylar head from translating too far forward, which is a common cause of dislocation.

4. Postoperative Care:

   • Following the procedure, patients may require a period of recovery and rehabilitation. This may include:
     • Dietary Modifications: Soft diet to minimize stress on the TMJ during the healing process.
     • Pain Management: Use of analgesics to manage postoperative discomfort.
     • Physical Therapy: Exercises to restore normal function and range of motion in the jaw.

5. Outcomes:

   • The Dautrey procedure has been shown to be effective in preventing recurrent TMJ dislocations. Patients often experience improved joint stability and a better quality of life following the surgery. Successful outcomes can lead to reduced pain, improved jaw function, and enhanced overall satisfaction with treatment.

Suture Materials

Sutures are essential in surgical procedures for wound closure and tissue approximation. Various types of sutures are available, each with unique properties, advantages, and applications. Below is a summary of some commonly used suture materials, including chromic catgut, polypropylene, polyglycolic acid, and polyamide (nylon).

1. Chromic Catgut

• Description:

  • Chromic catgut is a natural absorbable suture made from collagen derived from the submucosa of sheep intestines or the serosa of beef cattle intestines. It is over 99% pure collagen.

• Absorption Process:

  • The absorption of chromic catgut occurs through enzymatic digestion by proteolytic enzymes, which are derived from lysozymes contained within polymorphonuclear leukocytes (polymorphs) and macrophages.

• Absorption Rate:

  • The absorption rate depends on the size of the suture and whether it is plain or chromicized. Typically, absorption is completed within 60-120 days.

• Applications:

  • Commonly used in soft tissue approximation and ligation, particularly in areas where a temporary support is needed.

2. Polypropylene (Proline)

• Description:

  • Polypropylene is a synthetic monofilament suture made from a purified and dyed polymer.

• Properties:

  • It has an extremely high tensile strength, which it retains indefinitely after implantation. Polypropylene is non-biodegradable, meaning it does not break down in the body.

• Applications:

  • Ideal for use in situations where long-term support is required, such as in vascular surgery, hernia repairs, and other procedures where permanent sutures are beneficial.

3. Polyglycolic Acid

• Description:

  • Polyglycolic acid is a synthetic absorbable suture formed by linking glycolic acid monomers to create a polymer.

• Properties:

  • It is known for its predictable absorption rate and is commonly used in various surgical applications.

• Applications:

  • Frequently used in soft tissue approximation, including in gastrointestinal and gynecological surgeries, where absorbable sutures are preferred.

4. Polyamide (Nylon)

• Description:

  • Polyamide, commonly known as nylon, is a synthetic non-absorbable suture that is chemically extruded and generally available in monofilament form.

• Properties:

  • Nylon sutures have a low coefficient of friction, making passage through tissue easy. They also elicit minimal tissue reaction.

• Applications:

  • Used in a variety of surgical procedures, including skin closure, where a strong, durable suture is required.