Original Article
Impact of Timing of Admission and Microvascular Reconstruction on Free Flap Success Rates in Traumatic Upper Extremity Defects Jonas Kolbenschlag, MD1,2 Kai Megerle, MD2,5
Marek Klinkenberg, MD2
1 Department of Plastic Surgery, BG University Hospital
Bergmannsheil, Ruhr University Bochum, Bochum, Germany 2 Department for Hand, Plastic and Reconstructive Surgery, BG Trauma Center, Ludwigshafen, Germany 3 Department of Plastic and Reconstructive Surgery, Protestant Hospital Göttingen – Weende, Göttingen, Germany 4 Ethianum Clinic for Plastic and Reconstructive Surgery, Aesthetic and Preventive, Heidelberg, Germany 5 Clinic for Plastic Surgery and Hand Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
Susanne Hellmich, MD2,3
Günter Germann, MD4
Address for correspondence Jonas Kolbenschlag, MD, Department of Plastic Surgery, BG University Hospital Bergmannsheil, Bürkle-de-laCamp-Platz 1, Bochum, Germany (e-mail: [email protected]).
J Reconstr Microsurg 2015;31:414–419.
Abstract
Keywords
► free flap ► timing ► microsurgical reconstruction ► upper extremity ► coagulation ► platelets ► trauma
received December 30, 2014 accepted after revision February 4, 2015 published online March 24, 2015
Background Despite a growing body of knowledge, the timing of microsurgical reconstruction for the upper extremity remains a controversial topic. Most of the available literature deals with lower extremity reconstruction and the few reports on microsurgical reconstruction of the upper extremity are mostly concerned with infection rates and rarely consider thrombosis and changes in coagulation parameters. Methods We performed a retrospective review of all free flaps performed for upper extremity reconstruction at our institution from 2000 to 2010. Only acute, isolated traumatic defects of the upper extremity requiring a free flap for reconstruction were included in this study. A review of medical records was performed to assess, among others, comorbidities, timing of reconstruction, and platelet levels. Results A total of 41 patients were included in this study, 70% of whom were male. Mean age at the time of surgery was 40.8 15.4 years. Patients who were directly referred to our hospital underwent reconstruction significantly faster than those who were transferred secondarily (p ¼ 0.0001). The number of surgical revisions as well as the flap loss rate was higher in patients undergoing reconstruction more than 1 week after trauma (p ¼ 0.09 and 0.033, respectively). A significantly higher platelet count was seen in the patients undergoing delayed reconstruction (p ¼ 0.002). Conclusion In our study, early microsurgical reconstruction of the upper extremity yielded better results in terms of lower rates of surgical revisions and flap loss. This might be partly because of a trauma-induced thrombocythemia, with a maximum level of platelets in the 2nd week post trauma. We, therefore, advocate a timely coverage of these defects along with an anticoagulatory regimen including some form of platelet inhibition.
Copyright © 2015 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA. Tel: +1(212) 584-4662.
DOI http://dx.doi.org/ 10.1055/s-0035-1548550. ISSN 0743-684X.
Downloaded by: University of Florida. Copyrighted material.
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Patients and Methods This study was conducted in accordance with the declaration of Helsinki and local regulations. All patients undergoing microsurgical reconstruction at our institution over a period of 10 years were screened for inclusion using a prospectively maintained database. To be eligible for inclusion, patients had to have an isolated, acute traumatic soft-tissue defect of the hand or forearm necessitating microsurgical reconstruction. Amputation injuries were excluded. Out of the over 760 free flaps performed during this period, a total of 41 patients matched these criteria. After identification of the patients, we conducted a retrospective chart review recording the patient’s sex, age, comorbidities, size and etiology of the defect, type of flap used, and thrombocyte count. Also, the number of surgical revisions performed and the time between trauma and coverage of the defect were recorded. Laboratory findings were extracted from the most recent blood work obtained before the surgery, in all cases less than 24 hours before reconstruction. Perioperative anticoagulation consisted of 500 mL hydroxyethyl starch and 15.000 units of unfractionated heparin per 24 hours for a total of 5 days.
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Of the 41 patients included, 29 (70%) were male and the mean age at the time of surgery was 40.8 15.4 years. A total of 17 patients (40%) were active smokers, 11 (27%) suffered from obesity, and 1 patient suffered from diabetes. For comparison between groups, Student t-test and Fisher exact test were used. A significance level of p < 0.05 was assumed. Results are displayed as standard deviation (SD).
Results Primary Referral Out of the 41 patients included, 22 were referred directly to our department (52%). These patients underwent 1.41 1.3 surgical interventions before defect coverage was achieved (range, 1–5). Negative pressure wound therapy (NPWT) was used as a bridging tool in 11 patients for a duration of 5.2 2.9 days (range, 1–12 days). The mean duration from trauma to flap coverage was 6.85 7 days (range, 0–36 days). Three flap losses occurred in this group (14% flap loss rate, 50% of total flap losses). The mean duration of total hospital stay for directly referred patients was 42.5 14.8 days (range, 12–71 days).
Secondary Referral A total of 19 patients were transferred to our hospital 13.6 11.9 days after trauma (range, 1–35 days). These patients underwent 3.3 2 surgical interventions before defect coverage was achieved (p ¼ 0.0006). NPWT was applied in 10 patients for 10.9 11.1 days (range, 4–42 days). In this group, the time to definitive coverage of the defect was significantly longer (22.8 15 days, p ¼ 0.0001). Three flap losses occurred in this group (16% flap loss rate, 50% of total flap losses). The mean duration of total hospital stay for patients who were referred secondarily was 50.5 15.2 days (p ¼ 0.11).
Reconstruction within 7 Days A total of 17 patients underwent reconstruction within 1 week after trauma. Five flaps (12%) were performed as emergency free flaps within 24 hours after injury, the remaining 12 (28%) were performed during the first 2 to 7 days post trauma. Thirteen defects were located on the hand and four on the forearm. Parascapular flaps were used in most cases (five), followed by anterior lateral thigh (ALT) flaps and serratus fascia flaps in three cases each. Of the total of 14 surgical revisions, only three had to be performed in this group (2 thrombosis, 1 infection). All three flaps that underwent revision could be salvaged. The mean preoperative thrombocyte count in this group was 252.8 119 103/μL. The mean duration of hospital stay for patients who underwent reconstruction within 1 week was 34.1 14.9 days.
Delayed Reconstruction (> 7 days) A total of 24 patients underwent delayed reconstruction more than 1 week after trauma. Nine (21%) and five (12%) microsurgical reconstructions were performed during the 2nd and 3rd week, respectively. Journal of Reconstructive Microsurgery
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Reconstructive microsurgery has made tremendous progress in the last decades. Because of improvements in technique and perioperative care, outcomes have considerably improved.1 In the past, improvement of microsurgical techniques and development of new flap variations were the primary focus of interest, leading to an impressive armamentarium of reconstructive options.2 Nowadays, the success rate of microsurgical reconstruction has reached a level which can hardly be increased any further solely on technical improvements. Therefore, the focus of interest has shifted toward optimizing patient selection, timing of surgery, and perioperative care to further optimize the reconstructive outcomes.1 One of the earliest articles dealing with factors influencing the reconstructive outcome is Godina’s landmark article from 1986.3 Based on his findings in 532 microsurgical reconstructions of the lower extremities, he proposed that definitive free flap coverage should be achieved within 72 hours after injury for best outcomes. This “golden window” has been challenged by several authors in recent years, although most of the literature deals with lower extremity reconstruction.4–6 However, there are also reports that back up Godina’s findings, making the timing of lower extremity reconstruction a controversial topic up to date.7 Regarding microsurgical reconstruction of the upper extremity, a recent meta-analysis was able to identify only 15 articles dealing with this topic. The reported results were heterogeneous concerning the impact of timing on free flap complication rates.8 While all of these articles gave the number of total flap losses (range, 0–10%), only a few reported the number of surgical revisions or the incidence of microvascular thrombosis. Also, no study examined the potential coagulatory abnormalities of these patients. Therefore, the aim of our study was to further elucidate the influence of the timing of referral and reconstruction on the rates of flap failure and surgical revisions, as well potential coagulatory abnormalities in these patients.
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Kolbenschlag et al.
The remaining 10 flaps (22%) were performed more than 3 weeks after trauma. Sixteen defects were located on the hand and eight on the forearm. Eleven of the 14 flaps (78%) that had to undergo surgical revision were performed more than 1 week after trauma. Of these revisions, six were due to thrombosis of the pedicle thrombosis and five were due to infections. The rate of revision was noticeably higher for both infections and thrombosis in the 24 patients who received coverage later on; however, this difference was not statistically significant (p ¼ 0.09). Five of those 11 flaps could be salvaged, resulting in six total flap losses (salvage rate: 45%). The rate of flap losses was significantly higher in this group (p ¼ 0.033). The mean duration of hospital stay for patients who underwent reconstruction more than 1 week after injury was 39.4 13.9 days (p ¼ 0.25). The mean preoperative thrombocyte count in this group was significantly higher than in the group undergoing early reconstruction (451.27 147.97 103/μL; p ¼ 0.002). For a summary of these findings, see ►Table 1 and ►Fig. 1. The case of an ALT emergency free flap is depicted in ►Figs. 2–4.
Fig. 1 Distribution of performed flaps, surgical revisions, and flap losses depending on timing of defect coverage.
Discussion The need for microsurgical reconstruction of the upper extremity often arises from large complex defects with exposed tendons, neurovascular bundles, joints, or bone.9–11 Such defects can seriously affect upper extremity function and also have social and psychological consequences.12 To preserve the inherent function of the exposed structures, timely and adequate soft-tissue coverage is mandatory for optimal functional recovery.13,14 Earlier publications have advocated immediate reconstruction,3,15–17 while Derderian et al found complication rates to be lowest in a subacute period between days 6 to 21.18 Kumar et al in accordance to a recent meta-analysis also found no advantages of immediate reconstruction.8,19 In our study, however,
Fig. 2 A 29-year-old patient who sustained a traumatic injury of the dorsal lower arm and hand due to a grinder.
Table 1 Demographic data of patients, location of defects, type of flaps used, and thrombocyte count (in 103/μL) for patients undergoing microvascular tissue transfer within and after 1 week post trauma 1 wk
Sex (m:f)
12:5
17:7
Age
43.4 18
38.9 12
Forearm
4
8
Hand
13
16
Parascapular
5
8
Serratus fascia
3
5
Latissimus dorsi
2
4
ALT
3
3
Other flaps
4
4
Thrombocytes
252.8 119
445.45 151
Abbreviation: ALT, anterolateral thigh flap. Journal of Reconstructive Microsurgery
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Fig. 3 Early postoperative view of the emergency anterolateral thigh flap, performed immediately after surgical debridement.
we found lower rates of infection, thrombosis of the anastomoses, and total flap losses in the patients undergoing reconstruction within 1 week after trauma. A variety of factors have been mentioned as possible reasons for these findings, including less edema and inflammation as well as lower rates of bacterial contamination and subsequent
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Fig. 4 Two weeks postoperatively, the flaps showed adequate healing without the need for surgical revision.
infections.3,15,16 But as most of these factors deal with infection rather than thrombotic occlusion of the microvascular anastomoses, they can hardly be blamed for the higher revisions rate we observed because of thrombotic incidences in patients undergoing delayed reconstruction. Trauma, on the other hand, is known to trigger various changes in the coagulatory system, known as trauma-induced coagulopathy (TIC).20 A central part of these changes is the increased mobilization of platelets, resulting in a posttraumatic thrombocythemia. As these platelets can be dysfunctional to some extent, both hemorrhage and thrombosis can occur in these posttraumatic patients.21,22 Regarding the kinetics of posttraumatic thrombocythemia, a recent study found that the platelet count was lowest on the 3rd day after trauma, while the peak value was found 15 days after sustaining thermal injury.23 This is further supported by our findings, with significantly higher number of platelets found in the 2nd week after trauma. Although there is evidence that platelet (dys)function might be even more important for clot formation than their sheer number,24 they still account for a major part of it.25 While the majority of thrombotic occlusions of the microvascular anastomoses can be explained by technical errors or direct vessel trauma, coagulation seems to play an important role in recurrent thrombosis, ultimately leading to flap loss.26 This might especially be true in an anticoagulatory regimen with little direct platelet inhibition, similar to the one in our study population. It might also partly explain the difference in the findings of our foreign colleagues, as perioperative anticoagulation utilizing direct platelet inhibition is more common in the United States than in Germany.27,28 Therefore, if reconstruction has to be delayed, such patients might potentially benefit from platelet inhibition, for example, by acetylsalicyclic acid (ASA). ASA in combination with
Kolbenschlag et al.
heparin has proven to be superior to the sole administration of heparin for the prevention of thrombosis.29 Although the application of ASA in the face of major surgical interventions remains a controversial topic, the majority of evidence shows that it does not lead to an increased risk of bleeding.30–35 A recent study showed an increase in hematoma formation in patients who were administered ASA after deep inferior epigastric perforators flap breast reconstruction. Therefore, the authors stopped its routine use in these cases.36 However, in cases of highly increased numbers of thrombocytes, as described in this study or recurrent microvascular thrombosis, ASA might be beneficial.37,38 However, because of the limited data available concerning the impact of TIC and platelet function on microvascular thrombosis and the retrospective nature of this work, more research regarding these topics seems warranted to further elucidate potential connections between these findings. Even if the minimization of adverse events from a delayed reconstruction might be possible by such an anticoagulatory regimen, a timely coverage of the defect should be paramount. While most of the patients directly transferred to our hospital after trauma underwent microsurgical reconstruction within a week’s time, this was not true for those who were referred secondarily. For those patients, the time interval between trauma and coverage of the defect was nearly three times as long, resulting in inferior outcomes. This delay might be due to the fact that even severe isolated trauma to the upper extremity is not automatically referred to a designated trauma center, where the full spectrum of reconstructive surgery is provided. Often, serial debridements are performed and futile local coverage of the defect might be attempted because of the absence of microsurgical capabilities. This leads to the significantly higher amount of surgical interventions before definitive coverage of the defect can be achieved. Therefore, awareness of the potential problems of soft-tissue coverage of the upper extremity and the reconstructive possibilities should be raised to allow for faster reference to trauma centers and, therefore, faster care. This could also lead to shorter durations of hospital stay, which not only benefit the patients but also reduce health-care costs. If necessary, NPWT can be used as a bridging tool after adequate debridement. A recent study showed that this could potentially reduce complications in microsurgical reconstruction.39 Several limitations apply to this study. Although the highly significant difference in platelet counts between the 1st and 2nd weeks after trauma is striking, coagulation is much more complex and platelets are only one piece of the puzzle. Therefore, further work regarding platelet function and its course over time after trauma is needed. In addition, global screening tests of coagulation, such as rotational thromboelastometry, might be able to add valuable information regarding the coagulatory state of the trauma patient.26,40 In addition, the influence of comorbidities and smoking on flap revision rates and wound healing is well documented and might affect the results seen here.41 Also, the impact of an earlier reconstruction on functional outcome was not studied because of the retrospective nature of this work. Journal of Reconstructive Microsurgery
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Conclusion
15 Georgescu AV, Ivan O. Emergency free flaps. Microsurgery 2003;
According to our findings, early referral of patients with upper extremity defects that require microsurgical reconstruction to a dedicated center can significantly shorten the time to reconstruction and reduce the number of surgical interventions necessary. Such timely reconstruction also seems to be beneficial in terms of lower flap loss rates. We, therefore, advocate an immediate reference of such cases to microsurgical centers to allow for sufficient and timely care. Because of posttraumatic changes in coagulation, these patients might potentially benefit from an anticoagulatory regimen including some form of platelet inhibition.
16 Ninkovic M, Deetjen H, Ohler K, Anderl H. Emergency free tissue
23(3):206–216
17
18
19
20 21
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Kolbenschlag et al.
Journal of Reconstructive Microsurgery
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Impact of Timing of Admission and Microvascular Reconstruction on Free Flap Success Rates in Traumatic Upper Extremity Defects Jonas Kolbenschlag, MD1,2 Kai Megerle, MD2,5
Marek Klinkenberg, MD2
1 Department of Plastic Surgery, BG University Hospital
Bergmannsheil, Ruhr University Bochum, Bochum, Germany 2 Department for Hand, Plastic and Reconstructive Surgery, BG Trauma Center, Ludwigshafen, Germany 3 Department of Plastic and Reconstructive Surgery, Protestant Hospital Göttingen – Weende, Göttingen, Germany 4 Ethianum Clinic for Plastic and Reconstructive Surgery, Aesthetic and Preventive, Heidelberg, Germany 5 Clinic for Plastic Surgery and Hand Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
Susanne Hellmich, MD2,3
Günter Germann, MD4
Address for correspondence Jonas Kolbenschlag, MD, Department of Plastic Surgery, BG University Hospital Bergmannsheil, Bürkle-de-laCamp-Platz 1, Bochum, Germany (e-mail: [email protected]).
J Reconstr Microsurg 2015;31:414–419.
Abstract
Keywords
► free flap ► timing ► microsurgical reconstruction ► upper extremity ► coagulation ► platelets ► trauma
received December 30, 2014 accepted after revision February 4, 2015 published online March 24, 2015
Background Despite a growing body of knowledge, the timing of microsurgical reconstruction for the upper extremity remains a controversial topic. Most of the available literature deals with lower extremity reconstruction and the few reports on microsurgical reconstruction of the upper extremity are mostly concerned with infection rates and rarely consider thrombosis and changes in coagulation parameters. Methods We performed a retrospective review of all free flaps performed for upper extremity reconstruction at our institution from 2000 to 2010. Only acute, isolated traumatic defects of the upper extremity requiring a free flap for reconstruction were included in this study. A review of medical records was performed to assess, among others, comorbidities, timing of reconstruction, and platelet levels. Results A total of 41 patients were included in this study, 70% of whom were male. Mean age at the time of surgery was 40.8 15.4 years. Patients who were directly referred to our hospital underwent reconstruction significantly faster than those who were transferred secondarily (p ¼ 0.0001). The number of surgical revisions as well as the flap loss rate was higher in patients undergoing reconstruction more than 1 week after trauma (p ¼ 0.09 and 0.033, respectively). A significantly higher platelet count was seen in the patients undergoing delayed reconstruction (p ¼ 0.002). Conclusion In our study, early microsurgical reconstruction of the upper extremity yielded better results in terms of lower rates of surgical revisions and flap loss. This might be partly because of a trauma-induced thrombocythemia, with a maximum level of platelets in the 2nd week post trauma. We, therefore, advocate a timely coverage of these defects along with an anticoagulatory regimen including some form of platelet inhibition.
Copyright © 2015 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA. Tel: +1(212) 584-4662.
DOI http://dx.doi.org/ 10.1055/s-0035-1548550. ISSN 0743-684X.
Downloaded by: University of Florida. Copyrighted material.
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Patients and Methods This study was conducted in accordance with the declaration of Helsinki and local regulations. All patients undergoing microsurgical reconstruction at our institution over a period of 10 years were screened for inclusion using a prospectively maintained database. To be eligible for inclusion, patients had to have an isolated, acute traumatic soft-tissue defect of the hand or forearm necessitating microsurgical reconstruction. Amputation injuries were excluded. Out of the over 760 free flaps performed during this period, a total of 41 patients matched these criteria. After identification of the patients, we conducted a retrospective chart review recording the patient’s sex, age, comorbidities, size and etiology of the defect, type of flap used, and thrombocyte count. Also, the number of surgical revisions performed and the time between trauma and coverage of the defect were recorded. Laboratory findings were extracted from the most recent blood work obtained before the surgery, in all cases less than 24 hours before reconstruction. Perioperative anticoagulation consisted of 500 mL hydroxyethyl starch and 15.000 units of unfractionated heparin per 24 hours for a total of 5 days.
415
Of the 41 patients included, 29 (70%) were male and the mean age at the time of surgery was 40.8 15.4 years. A total of 17 patients (40%) were active smokers, 11 (27%) suffered from obesity, and 1 patient suffered from diabetes. For comparison between groups, Student t-test and Fisher exact test were used. A significance level of p < 0.05 was assumed. Results are displayed as standard deviation (SD).
Results Primary Referral Out of the 41 patients included, 22 were referred directly to our department (52%). These patients underwent 1.41 1.3 surgical interventions before defect coverage was achieved (range, 1–5). Negative pressure wound therapy (NPWT) was used as a bridging tool in 11 patients for a duration of 5.2 2.9 days (range, 1–12 days). The mean duration from trauma to flap coverage was 6.85 7 days (range, 0–36 days). Three flap losses occurred in this group (14% flap loss rate, 50% of total flap losses). The mean duration of total hospital stay for directly referred patients was 42.5 14.8 days (range, 12–71 days).
Secondary Referral A total of 19 patients were transferred to our hospital 13.6 11.9 days after trauma (range, 1–35 days). These patients underwent 3.3 2 surgical interventions before defect coverage was achieved (p ¼ 0.0006). NPWT was applied in 10 patients for 10.9 11.1 days (range, 4–42 days). In this group, the time to definitive coverage of the defect was significantly longer (22.8 15 days, p ¼ 0.0001). Three flap losses occurred in this group (16% flap loss rate, 50% of total flap losses). The mean duration of total hospital stay for patients who were referred secondarily was 50.5 15.2 days (p ¼ 0.11).
Reconstruction within 7 Days A total of 17 patients underwent reconstruction within 1 week after trauma. Five flaps (12%) were performed as emergency free flaps within 24 hours after injury, the remaining 12 (28%) were performed during the first 2 to 7 days post trauma. Thirteen defects were located on the hand and four on the forearm. Parascapular flaps were used in most cases (five), followed by anterior lateral thigh (ALT) flaps and serratus fascia flaps in three cases each. Of the total of 14 surgical revisions, only three had to be performed in this group (2 thrombosis, 1 infection). All three flaps that underwent revision could be salvaged. The mean preoperative thrombocyte count in this group was 252.8 119 103/μL. The mean duration of hospital stay for patients who underwent reconstruction within 1 week was 34.1 14.9 days.
Delayed Reconstruction (> 7 days) A total of 24 patients underwent delayed reconstruction more than 1 week after trauma. Nine (21%) and five (12%) microsurgical reconstructions were performed during the 2nd and 3rd week, respectively. Journal of Reconstructive Microsurgery
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Reconstructive microsurgery has made tremendous progress in the last decades. Because of improvements in technique and perioperative care, outcomes have considerably improved.1 In the past, improvement of microsurgical techniques and development of new flap variations were the primary focus of interest, leading to an impressive armamentarium of reconstructive options.2 Nowadays, the success rate of microsurgical reconstruction has reached a level which can hardly be increased any further solely on technical improvements. Therefore, the focus of interest has shifted toward optimizing patient selection, timing of surgery, and perioperative care to further optimize the reconstructive outcomes.1 One of the earliest articles dealing with factors influencing the reconstructive outcome is Godina’s landmark article from 1986.3 Based on his findings in 532 microsurgical reconstructions of the lower extremities, he proposed that definitive free flap coverage should be achieved within 72 hours after injury for best outcomes. This “golden window” has been challenged by several authors in recent years, although most of the literature deals with lower extremity reconstruction.4–6 However, there are also reports that back up Godina’s findings, making the timing of lower extremity reconstruction a controversial topic up to date.7 Regarding microsurgical reconstruction of the upper extremity, a recent meta-analysis was able to identify only 15 articles dealing with this topic. The reported results were heterogeneous concerning the impact of timing on free flap complication rates.8 While all of these articles gave the number of total flap losses (range, 0–10%), only a few reported the number of surgical revisions or the incidence of microvascular thrombosis. Also, no study examined the potential coagulatory abnormalities of these patients. Therefore, the aim of our study was to further elucidate the influence of the timing of referral and reconstruction on the rates of flap failure and surgical revisions, as well potential coagulatory abnormalities in these patients.
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The remaining 10 flaps (22%) were performed more than 3 weeks after trauma. Sixteen defects were located on the hand and eight on the forearm. Eleven of the 14 flaps (78%) that had to undergo surgical revision were performed more than 1 week after trauma. Of these revisions, six were due to thrombosis of the pedicle thrombosis and five were due to infections. The rate of revision was noticeably higher for both infections and thrombosis in the 24 patients who received coverage later on; however, this difference was not statistically significant (p ¼ 0.09). Five of those 11 flaps could be salvaged, resulting in six total flap losses (salvage rate: 45%). The rate of flap losses was significantly higher in this group (p ¼ 0.033). The mean duration of hospital stay for patients who underwent reconstruction more than 1 week after injury was 39.4 13.9 days (p ¼ 0.25). The mean preoperative thrombocyte count in this group was significantly higher than in the group undergoing early reconstruction (451.27 147.97 103/μL; p ¼ 0.002). For a summary of these findings, see ►Table 1 and ►Fig. 1. The case of an ALT emergency free flap is depicted in ►Figs. 2–4.
Fig. 1 Distribution of performed flaps, surgical revisions, and flap losses depending on timing of defect coverage.
Discussion The need for microsurgical reconstruction of the upper extremity often arises from large complex defects with exposed tendons, neurovascular bundles, joints, or bone.9–11 Such defects can seriously affect upper extremity function and also have social and psychological consequences.12 To preserve the inherent function of the exposed structures, timely and adequate soft-tissue coverage is mandatory for optimal functional recovery.13,14 Earlier publications have advocated immediate reconstruction,3,15–17 while Derderian et al found complication rates to be lowest in a subacute period between days 6 to 21.18 Kumar et al in accordance to a recent meta-analysis also found no advantages of immediate reconstruction.8,19 In our study, however,
Fig. 2 A 29-year-old patient who sustained a traumatic injury of the dorsal lower arm and hand due to a grinder.
Table 1 Demographic data of patients, location of defects, type of flaps used, and thrombocyte count (in 103/μL) for patients undergoing microvascular tissue transfer within and after 1 week post trauma 1 wk
Sex (m:f)
12:5
17:7
Age
43.4 18
38.9 12
Forearm
4
8
Hand
13
16
Parascapular
5
8
Serratus fascia
3
5
Latissimus dorsi
2
4
ALT
3
3
Other flaps
4
4
Thrombocytes
252.8 119
445.45 151
Abbreviation: ALT, anterolateral thigh flap. Journal of Reconstructive Microsurgery
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Fig. 3 Early postoperative view of the emergency anterolateral thigh flap, performed immediately after surgical debridement.
we found lower rates of infection, thrombosis of the anastomoses, and total flap losses in the patients undergoing reconstruction within 1 week after trauma. A variety of factors have been mentioned as possible reasons for these findings, including less edema and inflammation as well as lower rates of bacterial contamination and subsequent
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Fig. 4 Two weeks postoperatively, the flaps showed adequate healing without the need for surgical revision.
infections.3,15,16 But as most of these factors deal with infection rather than thrombotic occlusion of the microvascular anastomoses, they can hardly be blamed for the higher revisions rate we observed because of thrombotic incidences in patients undergoing delayed reconstruction. Trauma, on the other hand, is known to trigger various changes in the coagulatory system, known as trauma-induced coagulopathy (TIC).20 A central part of these changes is the increased mobilization of platelets, resulting in a posttraumatic thrombocythemia. As these platelets can be dysfunctional to some extent, both hemorrhage and thrombosis can occur in these posttraumatic patients.21,22 Regarding the kinetics of posttraumatic thrombocythemia, a recent study found that the platelet count was lowest on the 3rd day after trauma, while the peak value was found 15 days after sustaining thermal injury.23 This is further supported by our findings, with significantly higher number of platelets found in the 2nd week after trauma. Although there is evidence that platelet (dys)function might be even more important for clot formation than their sheer number,24 they still account for a major part of it.25 While the majority of thrombotic occlusions of the microvascular anastomoses can be explained by technical errors or direct vessel trauma, coagulation seems to play an important role in recurrent thrombosis, ultimately leading to flap loss.26 This might especially be true in an anticoagulatory regimen with little direct platelet inhibition, similar to the one in our study population. It might also partly explain the difference in the findings of our foreign colleagues, as perioperative anticoagulation utilizing direct platelet inhibition is more common in the United States than in Germany.27,28 Therefore, if reconstruction has to be delayed, such patients might potentially benefit from platelet inhibition, for example, by acetylsalicyclic acid (ASA). ASA in combination with
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heparin has proven to be superior to the sole administration of heparin for the prevention of thrombosis.29 Although the application of ASA in the face of major surgical interventions remains a controversial topic, the majority of evidence shows that it does not lead to an increased risk of bleeding.30–35 A recent study showed an increase in hematoma formation in patients who were administered ASA after deep inferior epigastric perforators flap breast reconstruction. Therefore, the authors stopped its routine use in these cases.36 However, in cases of highly increased numbers of thrombocytes, as described in this study or recurrent microvascular thrombosis, ASA might be beneficial.37,38 However, because of the limited data available concerning the impact of TIC and platelet function on microvascular thrombosis and the retrospective nature of this work, more research regarding these topics seems warranted to further elucidate potential connections between these findings. Even if the minimization of adverse events from a delayed reconstruction might be possible by such an anticoagulatory regimen, a timely coverage of the defect should be paramount. While most of the patients directly transferred to our hospital after trauma underwent microsurgical reconstruction within a week’s time, this was not true for those who were referred secondarily. For those patients, the time interval between trauma and coverage of the defect was nearly three times as long, resulting in inferior outcomes. This delay might be due to the fact that even severe isolated trauma to the upper extremity is not automatically referred to a designated trauma center, where the full spectrum of reconstructive surgery is provided. Often, serial debridements are performed and futile local coverage of the defect might be attempted because of the absence of microsurgical capabilities. This leads to the significantly higher amount of surgical interventions before definitive coverage of the defect can be achieved. Therefore, awareness of the potential problems of soft-tissue coverage of the upper extremity and the reconstructive possibilities should be raised to allow for faster reference to trauma centers and, therefore, faster care. This could also lead to shorter durations of hospital stay, which not only benefit the patients but also reduce health-care costs. If necessary, NPWT can be used as a bridging tool after adequate debridement. A recent study showed that this could potentially reduce complications in microsurgical reconstruction.39 Several limitations apply to this study. Although the highly significant difference in platelet counts between the 1st and 2nd weeks after trauma is striking, coagulation is much more complex and platelets are only one piece of the puzzle. Therefore, further work regarding platelet function and its course over time after trauma is needed. In addition, global screening tests of coagulation, such as rotational thromboelastometry, might be able to add valuable information regarding the coagulatory state of the trauma patient.26,40 In addition, the influence of comorbidities and smoking on flap revision rates and wound healing is well documented and might affect the results seen here.41 Also, the impact of an earlier reconstruction on functional outcome was not studied because of the retrospective nature of this work. Journal of Reconstructive Microsurgery
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15 Georgescu AV, Ivan O. Emergency free flaps. Microsurgery 2003;
According to our findings, early referral of patients with upper extremity defects that require microsurgical reconstruction to a dedicated center can significantly shorten the time to reconstruction and reduce the number of surgical interventions necessary. Such timely reconstruction also seems to be beneficial in terms of lower flap loss rates. We, therefore, advocate an immediate reference of such cases to microsurgical centers to allow for sufficient and timely care. Because of posttraumatic changes in coagulation, these patients might potentially benefit from an anticoagulatory regimen including some form of platelet inhibition.
16 Ninkovic M, Deetjen H, Ohler K, Anderl H. Emergency free tissue
23(3):206–216
17
18
19
20 21
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