Impact of liposome bupivacaine on the adequacy of pain management and patient experiences following aesthetic surgery: Results from an observational study.

BACKGROUND: Despite the efficacy of opioid analgesics for postsurgical pain, they are associated with side effects that may complicate recovery. Liposome bupivacaine is a prolonged-release formulation of bupivacaine approved for intraoperative administration at the surgical site for postsurgical analgesia. OBJECTIVES: To evaluate the effect of a single intraoperative administration of liposome bupivacaine on postsurgical pain, opioid use and opioid-related side effects in subjects undergoing breast surgery and/or abdominoplasty. METHODS: In the present phase IV, multicentre, prospective observational study, subjects received a single intraoperative administration (266 mg) of liposome bupivacaine. Rescue analgesia was available to all subjects as needed. Outcome measures, assessed through postoperative day 3, included postsurgical pain intensity (11-point numerical rating scale), opioid consumption and overall benefit of analgesic score. Results were evaluated comparing investigators' previous experience with similar surgeries. RESULTS: Forty-nine subjects entered the study: 34 underwent breast surgery only and 15 underwent abdominoplasty with or without breast surgery (six underwent breast surgery in addition to abdominoplasty). Mean numerical rating scale pain scores remained ≤4.3 from discharge through postoperative day 3. Median daily oral opioid consumption was approximately 1.0 tablet postoperatively on the day of surgery and was approximately 2.0 tablets by postoperative day 3. Mean overall benefit of analgesic score ranged between 2.8 and 4.9 throughout the study. CONCLUSION: In this particular subject population, liposome bupivacaine was associated with low pain intensity scores and reduced opioid consumption compared with the investigators' previous experiences. Subjects' satisfaction with postsurgical analgesia was high, with a low burden of opioid-related side effects.

HISTORIQUE: Malgré l'efficacité des opioïdes pour soulager la douleur postchirurgicale, des effets secondaires peuvent compliquer le rétablissement. La bupivacaïne liposomique est une formulation à libération prolongée approuvée pour l'administration peropératoire d'une analgésie postchirurgicale au site opératoire. OBJECTIFS: Évaluer l'effet de l'administration peropératoire d'une seule dose de bupivacaïne liposomique sur la douleur postchirurgicale, ainsi que sur l'utilisation d'opioïdes et leurs effets secondaires chez des sujets subissant une chirurgie mammaire, une abdominoplastie ou les deux interventions. MÉTHODOLOGIE: Dans le cadre de la présente étude d'observation prospective et multicentrique de phase IV, les sujets se sont fait administrer une seule dose peropératoire de bupivacaïne liposomique (266 mg). Tous les sujets pouvaient recevoir une analgésie de secours, au besoin. Les mesures des résultats, évaluées jusqu'au troisième jour postopératoire, incluaient l'intensité de la douleur postchirurgicale (sur une échelle numérique de onze points), la consommation d'opioïdes et les bienfaits globaux du score analgésique. Les chercheurs ont évalué les résultats en les comparant à leur expérience de chirurgies similaires. RÉSULTATS: Quarante-neuf sujets ont participé à l'étude : 34 ont subi seulement une chirurgie mammaire et 15, une abdominoplastie accompagnée ou non d'une chirurgie mammaire (six ont subi une chirurgie mammaire en plus de l'abdominoplastie). Les scores de douleur moyens sur l'échelle numérique ne dépassaient pas 4,3 entre le congé et le troisième jour postopératoire. La consommation quotidienne médiane d'opioïdes par voie orale après l'opération était d'environ 1,0 comprimé le jour de la chirurgie et d'environ 2,0 comprimés le troisième jour postopératoire. Les avantages globaux moyens du score analgésique se situaient entre 2,8 et 4,9 tout au long de l'étude. CONCLUSION: Au sein de cette population de sujets, la bupivacaïne liposomique s'associait à de faibles scores d'intensité de la douleur et à une consommation réduite d'opioïdes par rapport aux expériences passées des chercheurs. Les sujets étaient très satisfaits de l'analgésie postchirurgicale et présentaient un faible fardeau d'effets secondaires liés aux opioïdes.

Platelet gel sealant use in rhytidectomy.

BACKGROUND: A prospective study was used to evaluate the efficacy of a commercially available platelet gel product as a sealant to decrease postsurgical drain fluid rates and volumes in patients who have undergone rhytidectomy procedures. Quantitative assessments of postoperative drain fluid outputs were compared in subjects who did and did not receive platelet gel treatment. METHODS: Autologous platelet concentrate was prepared from each subject (n = 19), combined with bovine thrombin to form a platelet gel, and applied during the rhytidectomy procedure. Surgical drains were placed and effluent was collected postoperatively at 8-hour intervals for 24 hours and the volumes were recorded. A retrospective examination of surgical drain output over time in subjects (n = 14) who did not receive platelet gel treatment was performed; this group served as the control group. RESULTS: Subjects who received the platelet gel sealant treatment had significantly decreased surgical drain fluid levels over 24 hours [109 +/- 8.5 ml (mean +/- SEM)] compared with subjects who did not receive the platelet gel sealant (78 +/- 7.5 ml) (p < 0.02). From 0 to 8 hours postoperatively, platelet gel-treated subjects had a mean 35 percent decrease in fluid levels compared with the controls (p < 0.03). No difference in surgical drain outputs was observed from 8 to 16 hours between the two experimental groups. From 16 to 24 hours, the control group had increased mean fluid levels (20 percent) and the platelet gel sealant group output levels decreased (50 percent). CONCLUSIONS: Platelet gel sealant treatment was associated with decreased surgical fluid drain output in the first 24 hours postoperatively.

Autologous human fat grafting: effect of harvesting and preparation techniques on adipocyte graft survival.

BACKGROUND: Autogenous fat transfer with lipoinjection for soft-tissue augmentation is a commonly used technique without a universally accepted approach. The high percentage and variable amount of fat resorption reduce the clinical efficacy of this procedure and often result in the need for further grafting. The purposes of this study were to evaluate the effect of different harvesting and preparation techniques on human fat tissue viability and to determine fat tissue viability rates among the different fat preparations transplanted into a severe combined immune deficiency mouse model at 3 months. METHODS: Using standard liposuction and syringe aspiration, fat was removed from patients (n = 3) undergoing elective body contouring. Tissue was prepared by six different combinations of centrifugation and/or washing the cells with lactated Ringer's solution or normal saline. Metabolic activities of fat cell viability were monitored to assess overall cell viability. To analyze viability over 3 months, freshly harvested tissue specimens (minimum n = 5) were prepared by a combination of various procedures (wash, centrifugation, and different solutions) and subsequently injected under the dorsal flank skin of severe combined immune deficiency mice in two experiments. Mice were monitored for 12 weeks and the fat xenografts were removed for mass and histological evaluations. RESULTS: Metabolic analyses showed improved cell viability in tissue specimens undergoing minimal manipulation. No significant differences in fat cell viability, as assessed by graft weight maintenance or histologic evaluations, were observed with regard to harvesting or preparation techniques. CONCLUSIONS: Improved viability of freshly harvested but untreated fat specimens may be expected as compared with grafts that have undergone additional manipulations. No unique combination of preparation or harvesting techniques appeared to be more advantageous on transplanted fat grafts at 3 months. This study also demonstrated a reliable animal model for future investigation into examining novel applications for augmenting fat graft survival.

Pharmacokinetics and safety of epinephrine use in liposuction.

Patients are routinely exposed to high-dose epinephrine infiltration during large-volume liposuction. Because of the serious cardiovascular side-effect profile of catecholamine overdose, the authors examined the safety of larger-volume liposuction by assessing epinephrine pharmacokinetics. Five female volunteers with American Society of Anesthesiologists physical status of I or II, aged 29 to 40 years and weighing 75.9 to 95 kg, underwent liposuction. The wetting solution contained 7.3 mg (SEM, 0.7 mg) of epinephrine, corresponding to 0.09 mg/kg (0.04 mg/kg). Total plasma epinephrine and norepinephrine concentrations were assessed by high-performance liquid chromatography. Approximate exogenous epinephrine absorption was calculated after correction for estimated endogenous epinephrine production. Pharmacokinetic assessments were performed using standard equations. The total plasma epinephrine peak occurred at the final intraoperative reading (5 hours after induction) and was 323 pg/ml (24.8 pg/ml), three to four times maximum baseline resting levels. The norepinephrine level was slightly elevated throughout the study period, with a reversal of the normal epinephrine/norepinephrine ratio (<0.5:1) demonstrated intraoperatively (>5:1). Estimated time to peak exogenous epinephrine level ranged from 1 to 4 hours from the start of infiltration. Area under the plasma concentration versus time curve was approximately 2089 to 2610 pg x hour/ml. Peak exogenous epinephrine concentration was estimated to be 286 to 335 pg/ml. Clearance was 764,508 ml/hour and volume of distribution was 0.4 liter/kg (0.006 liter/kg). Total absorbed epinephrine was estimated, 1.8 mg to 2.2 mg, equivalent to 25 to 32 percent of the infiltrated dose. The reversal of the normal epinephrine/norepinephrine ratio and the fact that norepinephrine levels were within normal range implied that the majority of plasma epinephrine measured was exogenously infiltrated and not endogenously synthesized. On the basis of these observations, pharmacokinetic analyses were performed. Although unequivocal toxic epinephrine levels were not demonstrated, epinephrine peaks were three to four times the maximum observed in normal resting patients. Peak levels were comparable to those observed during major physiologic stresses, such as exercising to exhaustion, open abdominal surgery, or cross-clamping the aorta during surgical repair. Furthermore, epinephrine has been associated with myocardial infarction, arrhythmias, and fatal asystole in susceptible patients at these levels. Patients should be carefully screened for clinical evidence of hemodynamic and cardiac pathology before larger-volume liposuction is undertaken, as it may result in unnecessary high risk for patients who have preexisting cardiovascular disorders. Healthy American Society of Anesthesiologists physical status I or II patients should have sufficient cardiac reserve to tolerate these catecholamine levels.

Electrolyte and plasma enzyme analyses during large-volume liposuction.

Substantial fluid shifts occur during liposuction as wetting solution is infiltrated subcutaneously and fat is evacuated, causing potential electrolyte imbalances. In the porcine model for large-volume liposuction, plasma aspartate aminotransferase and alanine transaminase levels were elevated following liposuction. These results raised concerns for possible mechanical injury and/or lidocaine-induced hepatocellular toxicity in a clinical setting. The first objective of this human model study was to explore the effect of the liposuction procedure on electrolyte balance. The second objective was to determine whether elevated plasma aminotransferase levels were observed subsequent to large-volume liposuction. Five female volunteers underwent three-stage, ultrasound-assisted liposuction. Blood samples were collected perioperatively. Plasma levels of sodium, potassium, venous carbon dioxide, blood urea nitrogen, chloride, and creatinine were determined. Liver function analyte levels were measured, including albumin, total protein, aspartate aminotransferase, and alanine transaminase, alkaline phosphatase, gamma-glutamyl transpeptidase, and total bilirubin. To further define intracellular enzyme release, creatine kinase levels were measured. Mild hyponatremia was evident postoperatively (134 to 136 mmol/liter) in four patients. Hypokalemia was evident intraoperatively in all subjects (mean +/- SEM; 3.3 +/- 0.16 mmol/liter; range, 3.0 to 3.4 mmol/liter). Hypoalbuminemia and hypoproteinemia were observed throughout the study (baseline: 2.9 +/- 0.2 g/dl; range, 2.6 to 3.5 g/dl), decreasing to 10 to 40 percent 24 hours postoperatively (2.0 +/- 0.2 g/dl; range, 1.7 to 2.1 g/dl). Aspartate aminotransferase, alanine transaminase, and creatine kinase levels were significantly elevated after the procedure (190 +/- 47.1 U/liter, 50 +/- 7.7 U/liter, and 11,219 +/- 2556.7 U/liter, respectively) (p < 0.01). Release of antidiuretic hormone and even mildly hypotonic intravenous fluid infiltration have long been known to cause hyponatremia postoperatively. Intraoperative hypokalemia is associated with hypocarbia and respiratory alkalosis and the elevated epinephrine levels observed in the concurrent study. Factors having the greatest initial impact on diminished serum albumin and protein levels postoperatively are redistribution and hemodilution. Subsequent diminished viscosity may significantly affect postoperative hemodynamics. Elevated aspartate aminotransferase, alanine transaminase, and creatine kinase levels are associated with skeletal muscle injury, adipocyte lysis, and/or hepatic damage. Therefore, tissue injury is associated with large-volume liposuction as observed in several cellularly released enzymes. Future clinical studies are required to determine the degree of injury and specific tissues that are damaged or sensitive to mechanical trauma and/or drugs used in large-volume liposuction.

Hemodynamic physiology and thermoregulation in liposuction.

Little is known about the physiology of large-volume liposuction. Patients are exposed to prolonged procedures, general anesthesia, fluid shifts, and infusion of high doses of epinephrine and lidocaine. Consequently, the authors examined the thermoregulatory and cardiovascular responses to liposuction by assessing multiple physiologic factors. The aims of their study were to serially determine hemodynamic parameters perioperatively, to quantify perioperative and postoperative plasma epinephrine levels, and to chronologically document fluctuations in core body temperature. Five female volunteers with American Society of Anesthesiologists' physical status I and II underwent moderate- to large-volume liposuction. Heart rate, blood pressure, mean pulmonary arterial pressure, cardiac index, and central venous pressure were monitored. Serum epinephrine levels and core body temperature were assessed perioperatively. The hemodynamic responses to liposuction were characterized by an increase in cardiac index (57 percent), heart rate (47 percent), and mean pulmonary arterial pressure (44 percent) (p < 0.05). Central venous pressure was not significantly altered. Maximum epinephrine levels were observed 5 to 6 hours after induction. Significant correlations between cardiac index and epinephrine concentrations were shown intraoperatively (r = 0.75). All patients developed intraoperative low body temperatures (mean 35.5 degrees C). An overall enhanced cardiac function was observed in patients subsequent to large-volume liposuction. The etiology of the altered cardiac parameters was multifactorial but may have been attributable in part to the administration of epinephrine, which counters the effects of general anesthesia and operative hypothermia. Additional explanations for raised cardiac output may be hemodilution or emergence from general anesthesia. Elevated mean pulmonary arterial pressure may be a result of subclinical fat embolism demonstrated in previous porcine studies, although fat was not observed in urine. The unchanged central venous pressure levels indicate that young healthy patients with compliant right ventricles can accommodate the fluid loads of large-volume liposuction. Overall hemodynamic parameters remained within safe limits. Within these surgical parameters, patients should be clinically screened for cardiovascular and blood pressure disorders before liposuction is undertaken, and preventative measures should be taken to limit intraoperative hypothermia.

In search of improved fat transfer viability: a quantitative analysis of the role of centrifugation and harvest site.

Fat grafting is an unpredictable procedure that continues to challenge the field of plastic surgery due to irregular resorption. Applications for this procedure are broad in both reconstructive and cosmetic plastic surgery. Fat grafts are carefully obtained and manipulated to obtain better graft takes and results, yet there is no universal agreement on what constitutes an ideal methodology. The present study examines adipocyte viability from four commonly used donor sites in five subjects. No statistical differences in adipocyte viability were demonstrated among abdominal fat, thigh fat, flank fat, or knee fat donor sites that were immediately removed and untreated (p < 0.225). In addition, no differences were observed in representative tissue samples that were removed and centrifuged (thigh, p = 0.508; knee, p = 0.302; flank, p = 0.088; abdomen, p = 0.533). On the basis of these quantitative data, neither harvest location nor centrifugation demonstrated any advantage in terms of lipocyte viability. Fat tissue transfers from these common sites may be considered equal, and centrifugation does not appear to enhance immediate fat tissue viability before implantation.

Is the umbilicus truly midline? Clinical and medicolegal implications.

A common misconception is that the umbilicus is a midline structure. To date, an anatomical survey examining whether the umbilicus is located at the midline has not been reported. This study measured the position of the umbilicus among 136 subjects, in two separate experiments. The results demonstrated that the umbilicus was not at the midline for nearly 100 percent of subjects and was more than 2 percent from the midline for more than 50 percent of subjects. This finding is of great importance for patient counseling in preoperative and postoperative settings. Because the discerning eye has repeatedly been demonstrated to be able to detect smaller asymmetries, these findings are significant and should be discussed with patients undergoing cosmetic abdominoplasty or reconstructive procedures, for preoperative informed consent. Education and preoperative demonstration can help prevent medicolegal ramifications. The umbilicus is rarely midline and, when critically analyzed, is located lateral to the midline axis more often than not.

Recurrent mammary hyperplasia: current concepts.

LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Understand the factors leading to undesirable long-term reduction mammaplasty results. 2. Delineate the differential diagnosis of recurrent hypermastia. 3. Understand the significance of preoperative counseling, particularly with regard to expected postoperative outcome. 4. Understand short-term and long-term expected and undesirable postoperative results. 5. Understand safe and effective surgical planning for revision reduction mammaplasty. A large majority of patients who undergo reduction mammaplasty are satisfied with their aesthetic outcome and resolution of preoperative symptoms. Occasionally, patients present with postoperative concerns; these are usually aesthetic in nature and caused by breast scarring, breast asymmetry, and/or breast shape. Inadequate excision and recurrent hypermastia are more complex concerns, which require careful evaluation and treatment. Analysis of both the presenting deformity and the original surgical approach is critical in determining an operative plan. This article discusses the safe approach to revision reduction mammaplasty. Current concepts are discussed and presented. An algorithm for decision-making is presented and discussed.