LIPOSUCTION

Liposuction History

·  1921 - Dujarrier, a French surgeon, curetted a ballerina's knees with a uterine curette but the patient developed gangrene from femoral artery damage and required an amputation.

·  1964, Schrudde used small stab incisions with sharp curettage and suction of debris. Complicated by bleeding and seroma formation.

·  1978 Kesselring and Meyer added strong suction to sharp curettage – complications of bleeding and skin necrosis.

·  1983 Illouz described using blunt cannulas using a wet technique with hypertonic saline (aim to cause adipocyte swelling and lysis)

·  1983 Fournier favored using the syringe technique and a cross-tunneling technique. He popularised the dry technique.

·  1984 Hetter stressed importance of using adequate suction pressures

·  1982 Teimourian advocated small cannulas to minimise coutour deformities

·  1986 Fodor introduces the superwet technique

·  1987 UAL introduced by Zochhi

·  1990 Klein introduced tumescent technique using lignocaine up to 35mg/kg, performed under local anaesthesia with sedation

·  1992 Gasparotti – superficial liposuction

Indications

·  Lipoplasty is not an effective substitute for weight loss. Its use should be restricted to the removal of fat deposits which have failed to respond to diet and exercise.

·  Patients in good health, good skin tone and close to ideal body weight with

o  Primary modality to treat minimal to moderate localised fat deposits

o  Adjunct to more invasive lipectomy procedures – Le Jour breast reduction, submental plastymaplasty, combined abdominoplasty

o  Lipodystrophy

·  Also used in thinning flaps (post TRAM, groin flap) extravasation injuries, evacuation of hematomas post facelift, correction of axillary hyperhidrosis, buffalo hump and lymphedema.

Principles in liposuction management

1. appropriate patient selection

2. appropriate anatomical sites

3. attention to operative technique

4. careful selection of infiltrating solutions

5. adequate fluid management

6. good patient monitoring and documentation

7. postoperative compression garments.

Original technique

·  Illouz 1982

1)  Instill a hypotonic saline solution into areas of fat (theoretically to "rupture" the adipocytes).

2)  Insert blunt-tipped, hollow metal cannulas (of 5-, 8-, and 10-mm internal diameters with a lateral side opening) into these fatty deposits.

3)  Attach the cannulas via hose or tube to a high-power suction machine.

4)  Move these cannulas in and out of the fat in a fan-shaped pattern.

Advances

1)  smaller cannulas with blunt tips and more holes

  1. better contouring
  2. able to get to smaller anatomic regions
  3. less traumatic

2)  wetting solutions

Wetting solutions

Typical mixture:

  1. 1000ml Ringers warmed to 32°
  2. 1ml of 1:1000 Adrenaline =1:1,000,000
  3. 25ml of 2% lignocaine(20mg/ml) =0.05% =500mg

Risks of bleeding depends on:

  1. type of wetting solution
  2. site of liposuction
  3. number of passes
  4. size of cannula
  5. plane of liposuction – deep bleeds less

Estimation of blood loss

·  with dry technique, 1% drop in haematocrit for every 88ml of aspirate

·  with wet technique, 1% drop in haematocrit for every 150ml of aspirate(Hetter’s predictive rule of 150)

·  with superwet technique, 1% drop in haematocrit for every 250ml of aspirate

§  Using the 150 rule, liposuction under 1500mls should not drop the heamatocrit >10%, so unlikely to need blood transfusions

§  Due to the amount of blood loss associated with the dry technique, its use is not recommended except in limited applications with a volume of 100 cc of total aspirate or less

§  . The dry technique should never be used in conjunction with ultrasound-assisted liposuction.

Infiltration solution (tumescent)

Absorption rate in heavily infiltrated subcutaneous tissue is decreased due to

1)  infusion into a relatively avascular space

2)  local vasoconstriction

3)  absorption of lignocaine by adipocytes

4)  very dilute concentrations (lidocaine ≤0.1% and epinephrine ≤1:1,000,000).

·  Adrenaline

1)  0.07mg/kg but up to 10mg reported to be safe (PRS 1996), usual 4-5mg.

2)  Peak serum levels occur at 3hours (up to 4x normal)

3)  Return to normal at 12 hours

4)  Symptomatic reactions:anxiety, restlessness, tremor, weakness, headache, pallor, palpitations, nausea, and vomiting.

5)  Catecholamine overdose presents clinically with hypertension, chest pain, diaphoresis, tachycardia, paraesthesia of extremities, and cardiac arrhythmias.

6)  Adverse reactions may progress to hypotension, metabolic acidosis, pulmonary edema, asystole, and death

7)  use should be avoided in patients who present with pheochromocytoma, hyperthyroidism, severe hypertension, cardiac disease, or peripheral vascular disease.

§  Lignocaine

1)  Minimal concentration of 0.04% required for anaesthesia

2)  Evidence that using lignocaine reduces post-op analgesia requirements for 18-24 hours

3)  Peak serum levels occur at 12 hours

4)  Max dose 35mg/kg (Klein), 55mg/kg (Ostad) for tumescent technique - otherwise usual limit is 7mg/kg (with adrenaline)

5)  Side effects are:

  1. CNS – excitatory then depressant: light-headedness, nervousness, apprehension, euphoria, confusion, dizziness, drowsiness, tinnitus, blurred or double vision, vomiting, sensations of heat, cold or numbness, twitching, tremors, convulsions, unconsciousness, respiratory depression and arrest.
  2. CVS - usually depressant and are characterized by bradycardia, hypotension, and cardiovascular collapse, which may lead to cardiac arrest.

Is lignocaine necessary? - controversial

Perry PRS 1999 - study failed to show a significant difference in postoperative pain and concluded that lignocaine to be unnecessary in liposuction performed under general or epidural anesthesia.

§  Many plastic surgeons prefer to not have lignocaine in large volume liposuction and go with GA.

Reply by Jeff Klein:He feels GA is more dangerous

  1. the dose-dependent impairment of protective laryngeal reflexes and respiratory depression,
  2. the temptation to do too much liposuction on a single day
  3. multiple unrelated cosmetic surgical procedures on the same day
  4. thromboembolism associated with excessive surgical trauma
  5. iatrogenic pulmonary edema resulting from unnecessary use of intravenous fluids following tumescent infiltration.

When liposuction is done totally by local anesthesia, these risks are virtually eliminated. Because of the limits on total lidocaine dosage, the volume of liposuction is usually less than 3 liters of supranatant fat.

§  Marcaine, the longest-acting anesthetic in its class, is rapidly absorbed, has the slowest elimination in its class, and is not readily reversed. Marcaine toxicity affects the cardiovascular, neurologic, and hematologic systems and may result in cardiac arrhythmias, seizure, and coma with respiratory depression. Not recommended in wetting solutions

Large Volume Liposuction

With wet technique, Illouz observed the following:

§  If more than 500 ml of fat is re-moved, fluid replacement is required.

§  If more than 1500 ml of fat is re-moved, blood transfusion is required.

§  Those patients having removals of more than 2000 ml often required overnight observation and ongoing fluid replacement.

§  Major problems occur after 2500 to 3000 ml are removed.

§  As a general rule, excisions should not exceed 2000 ml, with 2500 ml being the upper limit.

§  Most commonly, large volume liposuction is defined as >4L of supernatant fat removed or >5L total volume.

§  The increase in adverse events with lipoplasty has been associated almost exclusively with large volumes of preinjectate and aspirated tissue, the risk of complications is unavoidably higher as the volume of fluid exchange increases

§  Large-volume liposuction combined with certain other procedures has resulted in serious complications, and such combinations should be avoided

Minimising Risks

1.  The surgeon must be properly trained and educated in liposuction techniques and have a thorough understanding of the physiologic changes that occur with regular and large volume liposuction.

2.  The anesthesiologist working with the surgeon also must be well trained and have a complete understanding of the physiology associated with infusion and removal of large volumes of fluids.

3.  The facility where the procedure is performed must be completely equipped to deal with any problem or complication that may occur during or after the procedure. The facility should be certified and accredited by a nationally recognized surgery accreditation body.

4.  The support staff working in the operating room and recovery room should be thoroughly trained and familiar with the procedure, care, and recovery of the patient.

  1. The patient must be selected appropriately for the procedure

§  Healthy mentally and physically, ASA<III

§  Not morbidly obese, stable weight

§  Realistic goals

§  Intraop monitoring

§  Keep patient warm – warming blankets, fluids, operating room

§  IDC

§  Calf compression pumps

§  Admit overnight for analgesia and fluid monitoring

§  Compressive garments

Fluid Management

§  Estimated that aspirate will contain 30% of the infiltrate – thus 70% will be absorbed into the blood stream.

Rohrich intraoperative fluid ratio (PRS Feb 2006)

§  intraoperative fluid ratio was defined as the sum of the super-wet infiltration volume plus the intraoperative intravenous fluid volume divided by the volume of aspiration.

§  He maintains intraoperative fluid ratios near 1.8 for small-volume reductions and 1.2 for large-volume aspirations

§  Despite this urine output was still high (2.9 ml/kg/hour and 2.5 ml/kg/hour for the small- and large-volume groups)

Residual fluid theory (G Commons, PRS 2001)

§  Uses the principle of Hypodermoclysis - the injection of large volumes of fluid into the tissues for hydration.

§  The residual volume represents the fluid available for autoresuscitation by hypodermoclysis

§  Residual fluid volume = total fluid volume in - total fluid volume out.

§  Total fluid volume in = total volume of wetting solution used + total volume of intravenous fluid used.

§  The total volume out = total volume of aspirated wetting solution (which is approximately 30 percent of the total aspirated volume in most cases) + urine output.

§  By retaining a residual volume of 120 ml/kg, fluid balance inconsistencies or difficulties can be avoided.

§  Relies heavily on the slow absorption of the wetting solution from the subcutaneous space in the postoperative period.

§  This is facilitated by compression garments and would prevent third spacing and further promote shifting of the fluid into the intravascular space.

Complications:

Major

  1. death : risk is 1:5000 (PRS 1999)
  2. causes
  3. pulmonary oedema
  4. cardiogenic
  5. noncardiogenic (increased capillary permeability) – ARDS
  6. epidural anaesthesia may worsen this by predisposing to vasodilatation and hypotension
  7. lignocaine toxicity – worsened by
  8. hepatic disease (metabolised in liver)
  9. renal disease
  10. cardiac disease
  11. hyperthyroidism – cardiac excitability
  12. hypovolumia (increased plasma levels)
  13. drug interactions (SSRI)
  14. hypothermia

5.  pulmonary thrombosis/DVT

6.  fat embolism syndrome

  1. penetration injuries
  2. lung
  3. cardiac
  4. bowel
  5. bleeding/haemorrhage and unplanned blood transfusions
  6. skin burns (UAL), necrosis

10.  infection, necrotising faciitis

Minor

  1. contour irregularities
  2. prolonged swelling
  3. scars
  4. seromas – more common with UAL. Treat with serial aspiration and postoperative compression
  5. nerve injuries - sensory changes
  6. skin blisters
  7. long term skin staining from hemosiderin

Equipment

Suction-assisted

§  High powered suction usually 1atm of negative pressure

§  End points of SAL

1.  Final contour

2.  Pinch test

Cannulas:

§  Multiple openings facilitate extraction of fat and traumatize the tissue less because repeated movement over a given area is minimized.

Power-assisted

§  Can be electrically or gas-driven, small motor drives the 2-4mm tip

§  Advantage in decreasing fatigue

§  Disadvantage: noisy and excessive vibration

Internal Ultrasound-assisted

§  Pioneered by Zocchi 1993

§  ultrasonic generator, which transmits electrical energy to a handpiece containing a piezoelectric crystal that converts the incoming electrical signal into a mechanical vibration at an ultrasonic frequency of 20–30 kHz with a cyclical displacement of around 100 μm.

§  Mechanism of action

1.  Cavitation

o  Sound waves consist of alternating expansion and compression cycles.

o  The compression phase exerts positive pressure in the medium, while expansion results from the negative pressure phase.

o  Ultrasound of sufficient intensity can produce microbubbles in a liquid or semiliquid medium during the expansion cycle. Rupture of these bubbles lead to microcavitation – causes emulsification of fat

o  Microcavitation can be observed at the tip of a UAL cannula, although the energy is rapidly dispersed.

o  Concern of free radical production and chromosomal damage

2.  Thermal effects

o  passage of heat through fatty tissue is poor, so that loss of heat may be limited – skin at particularly risk but also connective tissue

3.  Direct tissue effects

§  Benefits:

1.  Easier removal of fat from fibrous areas - gynecomastia, the back, upper abdomen, and posterior hip rolls.

2.  more even shaping of overlying skin surfaces

3.  less blood loss (probably the same as SAL, PRS 2001)

4.  less vascular disruption to flaps

5.  improved skin retraction

§  To prevent thermal injury

1.  never apply to dry tissue – usually superwet or tumescent

2.  cannula must be kept in motion

§  Procedure:

1.  Stage I: subcutaneous infiltration to decrease tissue density and blood loss

2.  Stage II: UAL to emulsify fat

3.  Stage III: evacuation of emulsified fat and final contouring with SAL

§  End points of UAL:

1.  Loss of tissue resistance

2.  blood tinged aspirate

§  Disadvantages

1.  skin burns/necrosis (4%)

o  entry burn - a skin protector is used at the entry site (longer incision)

o  tip burn – thermal end-hit – reduce risk by using adequate volume of wetting solution

o  devascularisation

2.  fat necrosis (4%)

3.  dysesthesias (6%) - potential for injury to myelin sheaths because of their high lipid content

4.  skin staining from hemosiderin

5.  high seroma rates – reduced with evacuation of emulsified fat

6.  rare risk of air embolus

7.  longer operating times

8.  potential damage to DNA – through the generation of free radicals

§  Recommendations (ANZ 2001)

1.  proper training in use of device – thermal injury and endpoints

2.  use as an adjunct to SAL

3.  use of submaximal amplitude settings except in very fibrous zones

4.  limiting treatment time

5.  not recommended for female breast contouring - The concern is that cancer of the breast that has not yet spread locally or remotely could do so.