Ronald E. Hoxworth

Validation of the Caprini Risk Assessment Model in Plastic and Reconstructive Surgery Patients

BACKGROUND The Venous Thromboembolism Prevention Study (VTEPS) Network is a consortium of 5 tertiary referral centers established to examine venous thromboembolism (VTE) in plastic surgery patients. We report our midterm analyses of the studys control group to evaluate the incidence of VTE in patients who receive no chemoprophylaxis, and validate the Caprini Risk Assessment Model (RAM) in plastic surgery patients. STUDY DESIGN Medical record review was performed at VTEPS centers for all eligible plastic surgery patients between March 2006 and June 2009. Inclusion criteria were Caprini score ≥3, surgery under general anesthesia, and postoperative hospital admission. Patients who received chemoprophylaxis were excluded. Dependent variables included symptomatic deep vein thrombosis (DVT) or pulmonary embolism (PE) within the first 60 postoperative days and time to DVT or PE. RESULTS We identified 1,126 historic control patients. The overall VTE incidence was 1.69%. Approximately 1 in 9 (11.3%) patients with Caprini score >8 had a VTE event. Patients with Caprini score >8 were significantly more likely to develop VTE when compared with patients with Caprini score of 3 to 4 (odds ratio [OR] 20.9, p < 0.001), 5 to 6 (OR 9.9, p < 0.001), or 7 to 8 (OR 4.6, p = 0.015). Among patients with Caprini score 7 to 8 or Caprini score >8, VTE risk was not limited to the immediate postoperative period (postoperative days 1-14). In these high-risk patients, more than 50% of VTE events were diagnosed in the late (days 15-60) postoperative period. CONCLUSIONS The Caprini RAM effectively risk-stratifies plastic and reconstructive surgery patients for VTE risk. Among patients with Caprini score >8, 11.3% have a postoperative VTE when chemoprophylaxis is not provided. In higher risk patients, there was no evidence that VTE risk is limited to the immediate postoperative period.

Postoperative enoxaparin prevents symptomatic venous thromboembolism in high-risk plastic surgery patients.

Background: Venous thromboembolism is a major patient safety issue. The Plastic Surgery Foundation–sponsored Venous Thromboembolism Prevention Study examined whether postoperative enoxaparin prevents symptomatic venous thromboembolism in adult plastic surgery patients. Methods: In 2009, four sites uniformly adopted a clinical protocol. Patients with a Caprini score of 3 or higher received postoperative enoxaparin prophylaxis for the duration of inpatient stay. Venous Thromboembolism Prevention Study historical control patients had an operation between 2006 and 2008 but received no chemoprophylaxis for 60 days after surgery. The primary study outcome was symptomatic 60-day venous thromboembolism. Results: Three thousand three hundred thirty-four patients (1876 controls and 1458 enoxaparin patients) were included. Notable risk reduction was present in patients with a Caprini score greater than 8 (8.54 percent versus 4.07 percent; p = 0.182) and a Caprini score of 7 to 8 (2.55 percent versus 1.15 percent; p = 0.230) who received postoperative enoxaparin. Logistic regression was limited to highest risk patients (Caprini score ≥7) and demonstrated that length of stay greater than or equal to 4 days (adjusted odds ratio, 4.63; p = 0.007) and Caprini score greater than 8 (odds ratio, 2.71; p = 0.027) were independent predictors of venous thromboembolism. When controlling for length of stay and Caprini score, receipt of postoperative enoxaparin was protective against venous thromboembolism (odds ratio, 0.39; p = 0.042). Conclusions: In high-risk plastic surgery patients, postoperative enoxaparin prophylaxis is protective against 60-day venous thromboembolism when controlling for baseline risk and length of stay. Hospitalization for 4 or more days is an independent risk factor for venous thromboembolism. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

The role of biologic mesh in abdominal wall reconstruction: a systematic review of the current literature

BACKGROUND Biologic mesh in the form of allograft or xenograft products have been used in complicated abdominal hernia repair, but few comparative studies exist. METHODS A systematic review of original incisional hernia studies was conducted to include 2 primary end points: hernia recurrence and surgical site occurrence. Analysis of variance and a Satterthwaite t test compared the devices. RESULTS Twenty-nine studies were included in this analysis, which included 1,257 patients. The total number of studies and the total subjects for each device include the following: Permacol (Tissue Science Laboratories, Hampshire, UK) (4/64), Surgisis (Cook Medical, Bloomington, IN) (3/87), and Alloderm (LifeCell, Corp, Branchburg, NJ) (23/1,106). Device-specific recurrence rates and surgical site occurrence rates, respectively, were as follows: Alloderm (20.8%, 31.4%), Permacol (10.9%, 25%), and Surgisis (8.0%, 40.2%). A Satterthwaite t test comparison revealed significantly higher numbers of hernia recurrence (P = .006) and surgical site occurrence (P = .04) when comparing Alloderm with Permacol. CONCLUSIONS Biologic mesh does play a beneficial role in abdominal wall reconstruction although allograft acellular dermal matrix does have a higher recurrence rate as compared with xenograft products, which limits its current role in hernia repair.

Assessment of postoperative venous thromboembolism risk in plastic surgery patients using the 2005 and 2010 Caprini Risk score.

Background: Venous thromboembolism is an important patient safety issue. The authors sought to compare the predictive capacity of the 2005 and 2010 Caprini Risk Assessment Models for perioperative venous thromboembolism risk. Methods: The authors performed a retrospective, observational, crossover study using an established surgical outcomes database. A total of 3334 adult plastic surgery patients were identified. Patients were risk-stratified using both the 2005 and 2010 Caprini Risk Assessment Models. Each patient served as his or her own control, resulting in precise matching for identified and unidentified confounders. The outcome of interest was 60-day, symptomatic venous thromboembolism. The predictive capacities of the 2005 and 2010 Caprini risk scores were compared. Results: Use of the 2010 Caprini Risk Assessment Model resulted in a systematic increase in the aggregate risk score. The median 2010 Caprini score was significantly higher than the median 2005 Caprini score (6 versus 5, p < 0.001). When compared with the 2010 model, the 2005 Caprini Risk Assessment Model was able to better separate the lowest and highest risk patients from one another. Patients classified as “super-high” risk (Caprini score >8) using the 2005 Caprini Risk Assessment Model were significantly more likely to have a 60-day venous thromboembolism event when compared with patients classified as super-high risk using the 2010 guidelines (5.85 percent versus 2.52 percent, p = 0.021). Conclusions: When compared with the 2010 Caprini Risk Assessment Model, the 2005 Caprini Risk Assessment Model provides superior risk stratification. The 2005 Caprini Risk Assessment Model is the more appropriate method to risk-stratify plastic surgery patients for perioperative venous thromboembolism risk. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.

The effect of postoperative enoxaparin on risk for reoperative hematoma.

Background: The risk of postoperative bleeding is the chief concern expressed by plastic surgeons who do not use pharmacologic prophylaxis against venous thromboembolism. The Plastic Surgery Foundation–funded Venous Thromboembolism Prevention Study examined whether receipt of postoperative enoxaparin prophylaxis changed 60-day reoperative hematoma rates. Methods: In 2009, the studys network sites uniformly adopted a “best practice” clinical protocol to provide postoperative enoxaparin to adult plastic surgery patients at risk for perioperative venous thromboembolism. Historical control patients (2006 to 2008) received no chemoprophylaxis for 60 days after surgery. Retrospective chart review identified demographic and surgery-specific risk factors that potentially contributed to bleeding risk. The primary study outcome was 60-day reoperative hematoma. Stratified analyses examined reoperative hematoma in the overall population and among high-risk patients. Multivariable logistic regression controlled for identified confounders. Results: Complete data were available for 3681 patients (2114 controls and 1567 enoxaparin patients). Overall, postoperative enoxaparin did not change the reoperative hematoma rate when compared with controls (3.38 percent versus 2.65 percent, p = 0.169). Similar results were seen in subgroup analyses for breast reconstruction (5.25 percent versus 4.21 percent, p = 0.737), breast reduction (7.04 percent versus 8.29 percent, p = 0.194), and nonbreast plastic surgery (2.20 percent versus 1.46 percent, p = 0.465). In the regression model, independent predictors of reoperative hematoma included breast surgery, microsurgical procedure, and post–bariatric surgery body contouring. Receipt of postoperative enoxaparin was not an independent predictor (odds ratio, 1.16; 95 percent CI, 0.77 to 1.76). Conclusion: Postoperative enoxaparin does not produce a clinically relevant or statistically significant increase in observed rates of reoperative hematoma. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk: II

Anatomy of the auriculotemporal nerve: variations in its relationship to the superficial temporal artery and implications for the treatment of migraine headaches.

BACKGROUND Clinical experience with surgical decompression of specific peripheral nerves in the head and neck for the relief of migraine headache symptoms has proven to be effective in most patients. Some patients, however, continue to have residual symptoms after these procedures. In an effort to better understand potential etiologies for failure of treatment, an investigation was performed to determine whether or not vascular-mediated peripheral trigger points exist that have heretofore been undescribed that may be contributing to persistent symptomatology. One such potential trigger point is the superficial temporal arterys interaction with the auriculotemporal nerve. A cadaveric investigation was performed to advance this anatomical understanding of this relationship. METHODS Both sides of 25 fresh cadaveric heads were dissected in the preauricular and temporal regions. The superficial temporal artery and auriculotemporal nerve were identified and dissected both proximally and distally. Their relationship was examined, and a topographical map of their intersections was generated. RESULTS The auriculotemporal nerve and superficial temporal artery run together in the superficial soft tissue in the preauricular and temple regions. A contiguous relationship between the two was found in 17 hemiheads (34.0 percent). CONCLUSIONS There are variations in the relationship between the auriculotemporal nerve and the superficial temporal artery. These variations may serve as an anatomical explanation for this point as a source of migraine headaches in some patients. A topographical map of the relationship between these two structures may serve as a guide for surgeons interested in decompressing the nerve from the artery when indicated.

The role of the columellar strut in rhinoplasty: Indications and rationale

Summary: There are a variety of techniques that can be used to enhance or improve the nasal tip. These techniques often use suture techniques and invisible grafts to achieve the desired result. The former methods have been well described throughout the literature. Among the latter techniques, the columellar strut remains a popular and effective form of an invisible graft in rhinoplasty. The purpose of this article is to define the role of the columellar strut graft, describe how to perform it correctly in rhinoplasty, provide a clinical algorithm for its application, and detail a 15-year retrospective analysis of the senior authors (R.J.R.) experience. Previous references to the importance of the columellar strut graft in rhinoplasty have been described; however, none has formally defined its singular importance in both primary and secondary open rhinoplasty. This article details the role of the columellar strut and its relationship to nasal tip projection and lower lateral cartilage symmetry with an explanation of methods for improving each. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

The pyriform ligament.

Background: Several ligaments are believed to support the nasal tip. Intraoperative dissection has suggested that a broader ligament may exist along the pyriform rim than has been previously noted. This observation, along with the concept that pyriform rim shape may affect nasal tip projection by ligamentous fixation, led to the present study. Methods: Ten hemifacial fresh cadaver dissections were performed. Sequential dissection was performed of tissue layers aided by magnification with loupes and an operating microscope. The fascial connection between pyriform rim bone and the upper and lower lateral cartilages and to the alar base was noted. The relationship of upper to lower lateral cartilage, and of the investing fascia to the lower lateral cartilage, was defined. Results: A dense fascial system was noted in all cadaver dissections arising from the periosteum of the pyriform rim. This ligamentous system inserted onto both the upper and lower lateral cartilages. It encompassed the previously described lateral sesamoid complex ligament and the ligament between the upper and lower lateral cartilage. This fascia has a consistent anatomical location and spans the pyriform rim from nasal bone to anterior nasal spine. Conclusions: A ligament exists between the pyriform rim and lateral cartilages and is broader and more expansive than previously described. It encompasses the previously described lateral sesamoid complex and the ligament between the upper and lower lateral cartilages. The consistent anatomical origin of this membrane suggests that the term “pyriform ligament” may be appropriate nomenclature. This ligament may be important in translating anatomical shape—and distortion—of the pyriform rim to the nasal cartilages, and may therefore affect tip shape, tip projection, and nasal vault architecture.

The effect of the columellar strut graft on nasal tip position in primary rhinoplasty.

Background: The columellar strut cartilage graft has historically been assumed to be a technique that increases tip projection. The purpose of this study was to retrospectively analyze a series of 100 consecutive rhinoplasty cases by the senior author (R.J.R) with a specific focus directed toward the effect of the columellar strut on final tip position, namely, tip projection and tip rotation. Methods: Medical information and digital images were obtained from 100 consecutive primary rhinoplasty patients. All postoperative images were obtained from 1-year or greater follow-up visits. Preoperative and postoperative digital images were compared using a software application that quantitatively analyzed various facial anatomical features, including the nasofrontal angle, the nasolabial angle, tip projection, and tip translation. Results: Tip projection (defined as the tip position on the x axis) actually decreased in 65 percent, increased in 27 percent, and was unchanged in 8 percent of subjects. Tip translation (defined as the tip position on the y axis) was decreased in 59 percent, increased in 34 percent, and unchanged in 7 percent. The nasofrontal angle was increased in 67 percent, decreased in 23 percent, and unchanged in 10 percent of patients. The nasolabial angle was increased in 46 percent, decreased in 34 percent, and unchanged in 20 percent. Conclusion: Use of the columellar strut cartilage graft does not necessarily imply an increase in tip projection, but rather serves as a means of unifying the nasal tip and helping to control final tip position. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Primary breast augmentation today: a survey of current breast augmentation practice patterns.

A study was undertaken to survey current practice patterns concerning primary breast augmentation. Members of the American Society for Aesthetic Plastic Surgery (ASAPS) were electronically surveyed concerning issues such as incision location, implant size and type, and complications, as well as information about the surgeons, their practices, and where procedures are performed. The survey response rate was 30%. Plastic surgeons from the South and Southwest made up 40% of respondents. Forty-six percent of respondents had more than 20 years of experience in practice. Forty-three percent of primary breast augmentations were performed in outpatient surgery centers. An anesthesiologist was in attendance in 60% of cases. The average operative time--indicated in 80% of responses--ranged from 45 to 90 minutes. Thirty-three percent of responding plastic surgeons used the base diameter to determine implant size and respondents most commonly used a smooth saline implant placed through an inframammary incision in a submuscular pocket. The most frequently reported complication was nipple sensation changes. Although the reintroduction of silicone gel implants was accompanied by expectations of a sharp increase in their use, this survey revealed that among ASAPS members, saline implants currently are used more often than silicone gel implants. However, both saline and silicone gel implants are used frequently, safely, and reliably. This survey represents a snapshot of current practice and future trends in primary breast augmentation will require additional assessment, although increased use of silicone gel breast prostheses over time is expected.