and Peter M. Prendergast2
(1)
Elysium Aesthetics, Bogota, Colombia
(2)
Venus Medical, Dublin, Ireland
Introduction
With the increase in the number and type of plastic surgical procedures that aim to improve the physical appearance and social acceptance, anesthesia can become the most feared factor by the patient, sometimes even more than the surgical procedure itself. It becomes necessary to educate the patient about the safety of the surgery and the anesthesia. Demystification of the anesthesia as a dangerous endeavor, diminishing the risk by an adequate preoperative evaluation, and performing the surgery according to the safety standards will keep high-definition lipoplasty as a safe, effective, and rewarding surgery.
We cannot forget certain issues that otherwise would disturb the desirable outcomes. These variables include lots of individual particularities, sometimes hard to figure out: from the socioeconomical level up to the particular environment for the postsurgical recovery.
It is always important to highlight and reassure all the advantages and disadvantages of the procedure and clear all the doubts, myths, and misinformation about the anesthesia. The patient is the only one who can decide about how the procedure is going to be done. For the body-contouring anesthesia, we must emphasize to the patient on how the preanesthetic drugs work and what is the appropriate pre- and postsurgical care and let them know all the possible complications of the anesthesia.
The type of anesthesia used for high-definition body sculpting depends on several factors, including the patient condition and preference, extent of procedure, staff, and facility.
This chapter describes the principles and technique for tumescent local anesthesia, monitored anesthesia care (MAC), and general anesthesia.
Preanesthesia
The first patient contact is done during the preanesthetic appointment. This must be done in a pleasant environment, with enough time and disposition to explain and clear all doubts. It is important to notice that not all the planned procedures can always be done; the possibility to perform the procedure depends in the findings of the past medical history and habits with the aim of looking for the best conditions of quality and security for the patient and the anesthesiologist.
It is always important to highlight the importance of the veracity of the information that the patient provides and letting them know that this information can be very useful to prevent complications and legal issues, and in the case of their appearance, a quick response can be provided.
Medical Record
Start the preanesthetic consultation emphasizing in establishing a good doctor-patient relationship. The questioning must be addressed to reveal the socioeconomic status of the patient with the aim of having a conversation that the patient can plenty understand and can retrieve accurate information about past medical history. When asking about their labor performance, we can get clues about the functional class that for this type of procedures must be I/IV according to the NYHA.
Always ask about the past allergy history to the drugs used in previous anesthesia and to food, environment, and other substances used in surgery (surgical tape, iodine solutions, latex, etc.) that in one or other way can alter the anesthesia process.
Take the vital signs to keep a record of the expected hemodynamic variables of the patient according to their past medical history and the medications he/she might be in. Include heart rate, blood pressure, oximetry at ambient, height, and weight. Calculate the body mass index, which must be lower than 30 to allow the procedure and to avoid complications such as ventilatory failure, thrombosis, long bedridden periods, delay in recovery, and probable displeasure with the final outcomes.
The patient classification using the New York Heart Association (NYHA) scale gives an idea of the cardiovascular risks, functional state, and some information about the patient’s habits. It is important to ask about past history of cardiovascular disease (hypertension, venous insufficiency, thromboembolic disease, myocardial ischemia or infarcts, arrhythmias), pulmonary disease (smoking, asthma, recent upper viral infections, COPD), urinary diseases (recent infections and how it was managed, chronic kidney disease), and gastrointestinal diseases (gastritis, bowel movements, irritable bowel syndrome). Remember also to note the received treatments, the efficacy of it, and the possible surgical and anesthetic issues of these treatments. All this information is valuable because the symptoms and management of any of these diseases can alter the recovery process even if the postsurgical pain is controlled and there are no surgical complications.
The past surgical history must include the number and type of procedures and surgical and anesthetic complications including dental work. Past traumatic history includes treatment, complications, sequels, and handicaps. Previous history of metabolic diseases like thyroid dysfunction or diabetes, must include: current management of the disease, last medical check-up, especific medical recommendations and latest blood tests.
The patient behavior is also important. Always ask about the use of tobacco, alcohol, and recreational drugs like cocaine, marihuana, LSD, heroin, amphetamines, etc.; check the time and frequency of use and signs of dependency. A period of at least 5 months of abstinence of tobacco, 15 days in the case of psychiatric medicines, and 3 days if there is alcohol use is recommended. We must always emphasize the importance of knowing these habits and warn the patient about the possible complications.
The physical examination must always include the vital signs record, blood pressure, heart rate, and oxygen saturation with the fraction of inspired oxygen of 21 %; weight; and height. Calculate the body mass index (BMI), which ideally must be below 30.
Normal value: 18.1–24.9
Overweight: 25.0–29.9
Obesity: >30.0.
Using this index, and considering the surgical blood looses, we calculate a safe volume of fat extraction:
Where FH: final hematocrit
HT: hematocrit
ivl: intra-surgical blood volume loss
tbv: total estimated blood volume
e: Euler’s constant (2.71828)
This formula lets us estimate the blood losses on every stage of the surgery and not in a linear manner like what is usually done.
The lab works must include the following: complete blood count checking for platelet and white cells condition, hemoglobin, hematocrit, coagulation times (prothrombin time/PT, INR, and partial thromboplastin time/PTT), renal function (creatinine and blood urea nitrogen/BUN), pregnancy test, HIV testing, and glycemia. When there is a known pathology like thyroid disease, the specific lab work must be addressed.
It is also important to take a 12-lead electrocardiogram (EKG) and chest X-rays even though most guidelines argue that these tests should not be taken on a healthy patient, but our the experience has shown that every day, we find many “healthy” patients with EKG abnormalities like arrhythmias, electric conduction alterations, and chest X-rays with signs of obstructive disease in young people.
Having this set of tests done, we can promptly plan a presurgical management if needed or definitely contraindicate the procedure.
After getting all the medical data collected and analyzed, we proceed to assign the anesthetic risk according to the American Society of Anesthesiologist (ASA) scale and the functional class according to the New York Heart Association (NYHA). By general rule, surgery is only performed in patients with an ASA scale of II/VI or lower.
Tumescent Anesthesia
Since the introduction of tumescent local anesthesia (TLA) in 1986, this method has been widely adopted for traditional liposuction and has an unprecedented safety record [1–4]. Intravenous sedation may be performed in combination with TLA to reduce discomfort and anxiety for the patient. There is a fine line between moderate sedation, deep sedation, and general anesthesia, so it is imperative that the anesthesiologist present has the equipment and monitoring available to convert to general anesthesia if required [5]. In cases of large volume, extensive high-definition body sculpting, general anesthesia may be desirable.
During tumescent anesthesia, a mixture of physiologic saline, lidocaine, epinephrine, and sodium bicarbonate are infiltrated into fatty tissue until a state of “tumescence” is reached. Tumescence is characterized by firm, swollen tissue that is turgid and somewhat fixed (Fig. 5.1). There are several reasons for the high safety profile of liposculpture performed under tumescent local anesthesia without IV sedation or general anesthesia:
Fig. 5.1
Tumescent anesthesia. Tumescent fluid is infiltrated until the tissues become firm and rigid. Note the blanching secondary to epinephrine-induced vasoconstriction
1.
The dilution of lidocaine with saline to concentrations of 0.05–0.1 % and dispersion in fatty tissue alters the pharmacokinetics entirely. The maximum safe dose of lidocaine with epinephrine increases from 7 to 55 mg/kg [6].
2.
Epinephrine has a dual role. It causes vasoconstriction in the subcutaneous fat, creating an almost bloodless field, and reduces blood loss to less than 1 % of liposuction aspirate. The vasoconstriction also slows systemic absorption of lidocaine so that serum levels of lidocaine rise slowly and peak only 4–14 h after infiltration [7].
