Abstract
Purpose
Various protocols exist to prevent thrombosis after free flap surgery in the head and neck. This study reviews the outcome and incidence of perioperative complications in patients undergoing head and neck reconstruction, simply using subcutaneous low-molecular-weight heparin.
Materials and methods
A total of 137 free tissue transfers performed between 2007 and 2010 were reviewed. All patients received a general thrombosis prophylaxis with subcutaneous low-molecular-weight enoxaparin. No aspirin, dextran, or additional antithrombotic medication was administered.
Results
Overall flap survival was 97.1%. A total of 3 complete and 1 partial flap loss occurred, all due to venous thrombosis. Five cases of venous congestion were successfully revised.
Conclusion
The free flap survival rate using simple subcutaneous heparin seems to be equivalent to other management regimens. Therefore, we suggest that no additional antithrombotic treatment is needed for patients who undergo head and neck reconstruction with free tissue transfer.
1
Introduction
Since the first free tissue transfer in 1959 by Seidenberg et al , free flap transplants have become the preferred method of reconstruction for complex defects in the head and neck. Success rates between 90% and 99% have been reported in the literature . Despite the reliability of microvascular procedures, loss of a free flap remains a serious concern. Most flap failures are due to microvascular thrombosis, generally occurring as venous thrombosis . Numerous protocols are described in the literature to prevent such an event ( Table 1 ). Intravenous heparin, low-molecular-weight dextran, and aspirin are frequently used as anticoagulant agents in patients undergoing microvascular reconstruction . However, there is no consensus on the ideal pharmacologic agent, dosing, efficacy, and, therefore, necessity. The purpose of this study was to evaluate the outcome of patients receiving no specific medication solely to improve flap perfusion. Only perioperative low-molecular-weight heparin as a prophylaxis for general thrombosis was given to the patient.
| Study | N | Medication | Free flap survival rate (%) | Thrombosis rate (%) | Revision rate (%) | Hematoma rate (%) | Salivary fistula (%) |
|---|---|---|---|---|---|---|---|
| Chalian et al 2001 | 156 | Heparin infusion 300 IU/kg bw/24 h for 5 d | 99 | No information | 3.8 | No information | No information |
| Intraoperatively 1500 IU heparin before releasing the vessel clamps | |||||||
| Eckardt et al 2003 | 500 | Dextran 40 for 24–48 h postoperatively | 94 | No information | 8 | No information | No information |
| Nakamizo et al 2004 | 187 | Prostaglandin E1 for 5 d postoperatively | 97.3 | 2.1 | 1.1 | 5.7 | 8.7 |
| Pohlenz et al 2007 | 202 | Heparin infusion 200 IU/kg bw/24 h | 97.1 | 2.9 | 8.4 | 2.5 | 2.5 |
| Chernichenko et al 2008 | 124 | Aspirin for 14 d postoperatively | 97.6 | 7.9 | No information | No information | No information |
| Fukuiwa et al 2008 | 102 | Prostaglandin E1 for 5 d postoperatively | 94.1 | 5.9 | No information | No information | No information |
2
Materials and methods
The charts of patients undergoing free flap reconstruction between March 1, 2007, and July 1, 2010, were retrospectively reviewed. Patients were operated in the ears, nose, and throat department of the Ludwig Maximilian University, Munich, and the ears, nose, and throat department of the Friedrich Alexander University, Erlangen, Germany. The identical peri- and postoperative protocol was applied at both institutes. Patient information, including sex, age, cause of free flap reconstruction, and the type of flap used, were sampled ( Tables 2-4 ). Furthermore, charts were reviewed for postoperative complications, in particular, free flap failures, salivary fistulas, and hematoma formation. Patients who did not receive the simple low-molecular-weight heparin protocol, for example, due to cardiac risk factors, were excluded from the study. All included patients received a standard protocol of low-molecular-weight enoxaparin (Clexane; Sanofi Aventis, Paris, France). Patients with low peri- and postoperative thrombosis risk received 20-mg enoxaparin once a day, starting at postoperative day 0. Patients with medium to high thrombosis risk (eg, respiratory diseases, bony reconstruction, etc) received 40 mg of enoxaparin, also starting at postoperative day 0 . This treatment was conducted daily until the patient was mobilized. Intraoperatively, no drainage was placed to the side of the neck where the vessel anastomoses were performed. After surgery, all patients were monitored in the intensive care unit. The head was maintained in a neutral position, and any mechanical compression in the neck was strictly avoided. Patients were kept pain free and well hydrated, whereas administration of more than 7 L of crystalloids was avoided to prevent further complications . Monitoring was performed on an hourly basis for the first 72 hours and every 2 hours on days 4 and 5, as flaps rarely fail after that period . Flap surveillance was performed mostly by trained nursing staff, supported by the microvascular surgeon, using clinical assessment and Doppler signal. Patients were dismissed from the intensive care unit on postoperative day 1, provided that the general condition of the patient at this time allowed it.
| n | Percentage | |
|---|---|---|
| Male | 83 | 64.9 |
| Female | 45 | 35.1 |
| Total | 128 | 100 |
| Average age | 51.8 |
| Site | n | Percentage |
|---|---|---|
| Radial forearm | 110 | 80.3 |
| Anterolateral thigh | 22 | 16.1 |
| Fibula | 5 | 3.6 |
| Total | 137 | 100 |
| Site | n | Percentage |
|---|---|---|
| Oropharyngeal | 66 | 48.2 |
| Oral soft tissue | 45 | 32.8 |
| Pharyngoesophageal | 18 | 13.2 |
| Oromandibular | 4 | 2.9 |
| Facial soft tissue | 3 | 2.2 |
| Midface | 1 | 0.7 |
| Total | 137 | 100 |
2
Materials and methods
The charts of patients undergoing free flap reconstruction between March 1, 2007, and July 1, 2010, were retrospectively reviewed. Patients were operated in the ears, nose, and throat department of the Ludwig Maximilian University, Munich, and the ears, nose, and throat department of the Friedrich Alexander University, Erlangen, Germany. The identical peri- and postoperative protocol was applied at both institutes. Patient information, including sex, age, cause of free flap reconstruction, and the type of flap used, were sampled ( Tables 2-4 ). Furthermore, charts were reviewed for postoperative complications, in particular, free flap failures, salivary fistulas, and hematoma formation. Patients who did not receive the simple low-molecular-weight heparin protocol, for example, due to cardiac risk factors, were excluded from the study. All included patients received a standard protocol of low-molecular-weight enoxaparin (Clexane; Sanofi Aventis, Paris, France). Patients with low peri- and postoperative thrombosis risk received 20-mg enoxaparin once a day, starting at postoperative day 0. Patients with medium to high thrombosis risk (eg, respiratory diseases, bony reconstruction, etc) received 40 mg of enoxaparin, also starting at postoperative day 0 . This treatment was conducted daily until the patient was mobilized. Intraoperatively, no drainage was placed to the side of the neck where the vessel anastomoses were performed. After surgery, all patients were monitored in the intensive care unit. The head was maintained in a neutral position, and any mechanical compression in the neck was strictly avoided. Patients were kept pain free and well hydrated, whereas administration of more than 7 L of crystalloids was avoided to prevent further complications . Monitoring was performed on an hourly basis for the first 72 hours and every 2 hours on days 4 and 5, as flaps rarely fail after that period . Flap surveillance was performed mostly by trained nursing staff, supported by the microvascular surgeon, using clinical assessment and Doppler signal. Patients were dismissed from the intensive care unit on postoperative day 1, provided that the general condition of the patient at this time allowed it.
