Faculty Bibliography

BACKGROUND: Trichloroacetic acid is routinely used by gynecologists to treat anogenital diseases, and accidental exposure to the health care providers may result in serious burns. This case serves to raise awareness of accidental exposure of trichloroacetic acid and describes preventive, first aid, and treatment recommendations that may limit the incidence and severity of burn injury among gynecologists. CASE: A 32-year-old female gynecologist incurred a deep second-degree, 12x14-cm, work-related chemical burn by unintentionally spilling a container of approximately 20 mL of 80% trichloroacetic acid onto her right thigh during an outpatient procedure. First aid included removal of her soaked clothing, 5 minutes of soap and cold water irrigation, and liberal placement of petroleum-based ointment onto the injury site. Treatment consisted of topical silver sulfadiazine cream twice a day, coverage with silver-impregnated silicone foam dressing, and a circumferential soft bandage to minimize sheer forces along the wound. A 9-month follow-up demonstrated a well-healed, mildly hypopigmented, aesthetically favorable wound with return of sensation. CONCLUSION: Accidental trichloroacetic acid burns are a potential hazard in a gynecology office. Health care workers should be familiar with prevention, first aid, and appropriate treatment that often can result in acceptable long-term outcomes.

BACKGROUND: The purposes of this study were to report a 7-year experience of microvascular reconstruction of scalp defects, compare flap type and outcomes, and evaluate the implications of short and long term complications. METHODS: Following institutional review board approval, a single surgeon's patients requiring microvascular scalp reconstruction were retrospectively reviewed from 2005 to 2011. Flap choice, complications, and outcomes were statistically analyzed. RESULTS: Nineteen patients met inclusion criteria (10 male and 9 female) with a mean age of 60.2 +/- 21.4 years (range, 23-90 years). All free tissue transfers (n = 20) achieved 100% soft tissue coverage. Mean size calvarial defect was 106.6 +/- 67.2 cm (range, 35-285 cm), with 11 requiring cranioplasty. Free flaps included the following: 13 anteriolateral thigh, 5 ulnar, 1 latissimus dorsi, and 1 thoracodorsal artery perforator. Mean flap size was 154.1 +/- 87.3 cm (range, 42-336 cm). Early complications (<30 days following surgery) occurred in 21.1% of patients and late complications (>30 days following surgery) in 52.6% of patients. Patients with an early complication were 2 times more likely to develop a late complication (relative risk, 2.1) but did not reach statistical significance. Late complications were more likely to require surgical intervention, 84.2% versus 60% of early complications (P = 0.079). CONCLUSIONS: Microvascular free tissue transfer is the mainstay of complex scalp defects but carries a high likelihood of future reoperations. Early complications are less concerning than late complications, as the need for future surgical intervention is associated with late complications. There is lack of evidence to support a superior flap choice.

INTRODUCTION: The anatomy of the facial artery, its tortuosity, and branch patterns are well documented. To date, a reliable method of identifying the facial artery, based on surface landmarks, has not been described. The purpose of this study is to characterize the relationship of the facial artery with several facial topographic landmarks, and to identify a location where the facial artery could predictably be identified. METHODS: Following institutional review board approval, 20 hemifacial dissections on 10 cadaveric heads were performed. Distances from the facial artery to the oral commissure, mandibular angle, lateral canthus, and Manson's point were measured. Distances were measured and confirmed clinically using Doppler examination in 20 hemifaces of 10 healthy volunteers. RESULTS: Manson's point identifies the facial artery with 100% accuracy and precision, within a 3 mm radius in both cadaveric specimens and living human subjects. Cadaveric measurements demonstrated that the facial artery is located 19 mm +/- 5.5 from the oral commissure, 31 mm +/- 6.8 from the mandibular angle, 92 mm +/- 8.0 from the lateral canthus. Doppler examination on healthy volunteers (5 male, 5 female) demonstrated measurements of 18 mm +/- 4.0, 50 mm +/- 6.4, and 79 mm +/- 8.2, respectively. CONCLUSIONS: The identification of the facial artery is critical for the craniofacial surgeon in order to avoid inadvertent injury, plan for local flaps, and in preparation of a recipient vessel for free tissue microvascular reconstruction. Manson's point can aid the surgeon in consistently indentifying the facial artery.

BACKGROUND: Fractures of the mandibular condyle are common following blunt facial trauma and carry an increased risk for concomitant blunt carotid artery injuries (BCAI), a potentially life-threatening complication. Further elucidation of the relationship between specific condylar fracture patterns and BCAI may improve vascular injury screening and management. METHODS: A retrospective cohort study was performed for all craniofacial trauma patients sustaining condylar fractures that presented to a large trauma center from 2000 to 2012. Condylar fracture locations were classified according to the Strasbourg Osteosynthesis Research Group (SORG) system (SORG 1: condylar head, SORG 2: condylar neck, SORG 3: extracapsular condylar base). BCAI severity was based on the Biffl scale. Severe BCAI was defined as a Biffl score greater than I. RESULTS: We identified 605 patients with mandibular condyle fractures consisting of 21.0% (n=127) SORG 1, 26.8% (n=162) SORG 2, and 52.2% (n=316) SORG 3. Overall incidence of BCAI in this population was 5.5%(n=33), of which 75.8 % (n=25) were severe. Severe BCAIs occurred in 1.6% (n=2) of SORG 1, 2.5% (n=4) of SORG 2, and 6.0% (n=19) of SORG 3 fractures (p<0.05). SORG 3 fractures were independently associated with a 2.94-fold increased risk of a severe BCAI compared to other condyle fractures on multivariable analysis (p-value <0.05). CONCLUSIONS: The presence of extracapsular subcondylar fractures should heighten suspicion for concomitant BCAI. Our data additionally support a force transmission mechanism of injury in addition to direct vascular injuries from bony fragments.

PURPOSE: Abdominal compartment syndrome (ACS) is a severe complication of ventral hernia repair. The aims of this study were to investigate the effects of intra-abdominal pressure on the physiologic changes of abdominal wall reconstruction and component separation in a porcine model. METHODS: Ventral hernia repair (VHR) was simulated by abdominal fascial imbrication of a 10 x 15 cm defect in 45 Yorkshire pigs assigned to five experimental groups. ACS was simulated by a Stryker endoscopy insufflator with intra-abdominal pressure elevated to 20 mmHg in two groups. Component separation was performed in one of these groups and in one group without ACS. Physiological parameters were measured before and after the procedures and monitored for 4 h. The animals were euthanized for histologic analysis of organ damage. RESULTS: VHR led to an increase in intra-abdominal pressure, bladder pressure, and central venous pressure by an average of 14.89, 13.93, and 14.69 mmHg (p < 0.001) in all animals. Component separation was performed in 25 animals and the three pressures reduced by 9.11, 8.00, 7.89 mmHg (p < 0.001). ACS correlated with higher percentages of large and small bowel necrosis compared to groups without abdominal compartment syndrome. CONCLUSIONS: The results confirm that primary repair of large abdominal wall defects leads to increased intra-abdominal pressure, which can be reduced with component separation. In animals with ACS, component separation may reduce the risk of organ damage. Central venous pressure, bladder pressure, and other physiologic parameters accurately correlated with elevated intra-abdominal pressure and may have utility as markers for diagnosis of ACS.

BACKGROUND: Composite mandibular tissue loss results in significant functional impairment and cosmetic deformity. This study classifies patterns of mandibular composite tissue loss and describes a microvascular treatment algorithm. METHODS: A retrospective review of microvascular composite mandibular reconstruction from July of 2005 to April of 2013 by the senior surgeon at the R Adams Cowley Shock Trauma Center and at The Johns Hopkins Hospital yielded 24 patients with a mean follow-up of 17.9 months. Causes of composite mandibular defects included tumors, osteoradionecrosis, trauma, infection, and congenital deformity. Patients with composite tissue loss were classified according to missing subunits. RESULTS: A treatment algorithm based on composite mandibular defects and microvascular reconstruction was developed and used to treat 24 patients. A type 1 defect is a unilateral dentoalveolar defect not crossing the midline and not extending into the angle of the mandible. A type 2 defect is a unilateral defect extending beyond the angle. A type 3 defect is a bilateral defect not involving the angles. A type 4 defect is a bilateral defect with extension into at least one angle. Type 2 defects were the predominant group. Patients had microvascular reconstruction using either fibula flaps (n = 19) or iliac crest flaps (n = 5). Complications included infection, partial necrosis, plate fracture, dehiscence, and microvascular thrombosis. CONCLUSION: This novel classification system and treatment algorithm allows for a consistent and reliable method of addressing composite mandibular defects and focuses on recipient vasculature and donor free flap characteristics. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

BACKGROUND: Multiple perfusion assessment technologies exist to identify compromised microvascular free flaps. The effectiveness, operability, and cost of each technology vary. The authors investigated surgeon preference and clinical behavior with several perfusion assessment technologies. METHODS: A questionnaire was sent to members of the American Society for Reconstructive Microsurgery concerning perceptions and frequency of use of several technologies in varied clinical situations. Demographic information was also collected. Adjusted odds ratios were calculated using multinomial logistic regression accounting for clustering of similar practices within institutions/regions. RESULTS: The questionnaire was completed by 157 of 389 participants (40.4 percent response rate). Handheld Doppler was the most commonly preferred free flap-monitoring technology (56.1 percent), followed by implantable Doppler (22.9 percent) and cutaneous tissue oximetry (16.6 percent). Surgeons were significantly more likely to opt for immediate take-back to the operating room when presented with a concerning tissue oximetry readout compared with a concerning handheld Doppler signal (OR, 2.82; p < 0.01), whereas other technologies did not significantly alter postoperative management more than simple handheld Doppler. Clinical decision making did not significantly differ by demographics, training, or practice setup. CONCLUSIONS: Although most surgeons still prefer to use standard handheld Doppler for free flap assessment, respondents were significantly more likely to opt for immediate return to the operating room for a concerning tissue oximetry reading than an abnormal Doppler signal. This suggests that tissue oximetry may have the greatest impact on clinical decision making in the postoperative period.