Research
ajog.org
OBSTETRICS
Suture versus staples for skin closure after cesarean: a metaanalysis Awathif Dhanya Mackeen, MD, MPH; Meike Schuster, DO; Vincenzo Berghella, MD OBJECTIVE: We sought to perform a metaanalysis to synthesize
randomized clinical trials of cesarean skin closure by subcuticular absorbable suture vs metal staples for the outcomes of wound complications, pain perception, patient satisfaction, cosmesis, and operating time. STUDY DESIGN: A systematic search was performed using MEDLINE,
Cochrane Databases, and ClinicalTrials.gov registries. We included randomized trials comparing absorbable suture vs metal staples for cesarean skin closure. Data were abstracted regarding wound complications, patient pain perception, patient satisfaction, cosmesis as assessed by the physician and patient, and operating time. RESULTS: Twelve randomized trials with data for the primary
outcome on 3112 women were identified. Women whose incisions were closed with suture were significantly less likely to have wound complications than those closed with staples (risk ratio, 0.49; 95% confidence interval [CI], 0.28e0.87). This difference remained
significant even when wound complications were stratified by obesity. The decrease in wound complications was largely due to the lower incidence of wound separations in those closed with suture (risk ratio, 0.29; 95% CI, 0.20e0.43), as there were no significant differences in infection, hematoma, seroma, or readmission. There were also no significant differences in pain perception, patient satisfaction, and cosmetic assessments between the groups. Operating time was approximately 7 minutes longer in those closed with suture (95% CI, 3.10e11.31). CONCLUSION: For patients undergoing cesarean, closure of the
transverse skin incision with suture significantly decreases wound morbidity, specifically wound separation, without significant differences in pain, patient satisfaction, or cosmesis. Suture placement does take 7 minutes longer than staples. Key words: cesarean, incision closure, staples, suture, wound complications
Cite this article as: Mackeen AD, Schuster M, Berghella V. Suture versus staples for skin closure after cesarean: a metaanalysis. Am J Obstet Gynecol 2015;212:621.e1-10.
C
esarean is one of the most common surgeries performed worldwide and rates are increasing despite efforts to the contrary.1 Many of the surgical steps have been individually assessed previously, eg, prophylactic antibiotic administration, development of the bladder flap, techniques for expansion of the uterine incision and removal of the placenta, closure of the uterine and fascial incisions, closure of the
subcutaneous space when 2 cm, and closure of the skin incision.1,2 Our previous systematic review as well as Dahlke et al1 concluded that the data remain conflicting with regards to whether it is better to close the cesarean skin incision with suture or with staples.3 Though optimizing the individual steps of a cesarean is important with respect to providing the best possible care for patients, the skin incision is the
From the Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Geisinger Medical Center, Danville (Drs Mackeen and Schuster), and Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia (Dr Berghella), PA. Received Aug. 25, 2014; revised Nov. 18, 2014; accepted Dec. 15, 2014. One of the trials included in this metaanalysis, for which A.D.M. and V.B. are authors, was supported by Ethicon Inc. After that study was designed and initiated, Ethicon Inc agreed to provide funds to assist with patient recruitment and follow-up. The funding source had no influence on study design, study execution, data analysis, or publication. Those funds were not used to support this metaanalysis. The authors report no conflict of interest. Corresponding author: Awathif Dhanya Mackeen, MD, MPH. [email protected] 0002-9378/$36.00 ª 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ajog.2014.12.020
visible reminder to a patient about her cesarean. Despite the potential complexity of the surgery, the occurrence of a wound complication may be the aspect that the patient most clearly recalls. In addition, wound complications may result in prolonged hospital stay, readmission, increased time away from work, decreased infant bonding time, and increased health care expenditures. Choice of closure continues to vary among clinicians, most commonly between absorbable subcuticular suture and nonabsorbable metal staples.4 Additional evidence, including a trial recently published by 2 authors of this metaanalysis, has emerged regarding the optimal closure of the cesarean skin incision.5 As such our goal was to examine the pertinent randomized clinical trials (RCTs) to evaluate the incidence of wound complications, pain perception, patient satisfaction, cosmesis, and operating time when the cesarean skin incision was closed with suture vs with staples.
MAY 2015 American Journal of Obstetrics & Gynecology
621.e1
Research M ATERIALS
AND
ajog.org
Obstetrics M ETHODS
Sources The principles embodied in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement were used in compiling this metaanalysis.5 MEDLINE via Ovid and PubMed searches were performed in July 2014 to encompass the past 50 years of trials; additionally the Cochrane Databases were searched and clinical trials were identified using Ovid and Clinical Key and by searching ClinicalTrials.gov. Ovid MEDLINE was searched using Medical Subject Headings (MeSH) without restrictions for text words or word variations for the following search terms: “cesarean,” “caesarean,” “suture,” “suture techniques,” “stitches,” “staple,” “surgical stapling,” “skin,” “closure,” “wound complications,” “wound infection,” “wound healing,” “wound closure,” “cicatrix,” “scar,” “randomized controlled trial,” and “randomized clinical trial.” “Humans” was set as the only limit. A second search was conducted in PubMed to identify nonindexed citations using the search terms “caesarean,” “cesarean,” “skin,” “wound complications,” “wound healing,” “wound infection,” “surgical wound infection,” “staple,” “suture,” “stitches,” and “trial.” There were no language restrictions applied. Searches were performed by a health sciences library specialist, a reference librarian, and the primary author (A.D.M.). This search was conducted as a brand new search and not part of the original Cochrane review or RCT by this author. As this is a metaanalysis, it was considered exempt from institutional review board approval. Study selection All identified abstracts were independently reviewed by the primary author (A.D.M.) and an additional author (V.B. or M.S.) and full articles were retrieved and reviewed for trials considered for inclusion. The primary author and additional author independently reviewed the manuscripts to assess for inclusion or exclusion criteria for this metaanalysis. We included only RCTs comparing subcuticular absorbable
suture with nonabsorbable metal staples for cesarean skin closure. We chose to exclude RCTs that compared absorbable staples, nonabsorbable suture, or stapling devices (Figure 1). We excluded ongoing trials; studies that assessed surgical techniques for cesarean, but not the skin incision; and studies that did not provide applicable data for inclusion in the metaanalysis (eg, abstracts that did not report sample size).
Study outcomes The primary outcome was wound complications. This was defined as a composite of wound infection, separation, hematoma, seroma, or readmission secondary to a wound concern. These were defined as per the individual trials. Secondary outcomes were patient pain perception at discharge, patient satisfaction at 2 months postoperatively, cosmesis as assessed by the physician and patient at 2 months postoperatively, and operative time. Patient pain perception and satisfaction were collated among studies if a 10-point scale was used, typically the visual analog scale in which higher scores represent higher patient satisfaction and more pain.6 Cosmesis was assessed if studies used the validated Physician Observer Scar Assessment Scale (OSAS) for assessment; this scale has both subjective (Physician Scar Assessment Scale [PSAS]) and objective (OSAS) components as scored by the patient and physician, respectively.7 Patient assessment of cosmesis (PSAS) was scored from 6-60 and physician assessment of cosmesis (OSAS) was scored from 5-50: lower scores are considered superior. When applicable, attempts were made to contact authors to obtain more detail on outcomes not clearly reported in the manuscript. Additionally we analyzed the primary outcome stratified by body mass index (2 cm
50/50
If >2.5 cm
50/50
Not stated
If 2 cm
If >2 cm
100%
50/50
None
Staple removal day
6
3e4 for 4 Pfannenstiel; 7e10 for vertical
3
7
10
7
3e4
3
6
At discharge
2e4 wk
6 wk
4 mo
6 wk
0e10 scale
Assessed based on author’s survey tool
10-cm Pain scale
Singer SES
Cosmesis based on author’s assessment scale
Subjective
4e10
398
Postoperative 4e8 wk follow-up for wound complications
Unclear, but it 4e6 wk appears this was performed at day 3 and at 6 wk
6 wk
3 mo
Unclear at what point these were assessed
Day 1, 3, and 10
2 mo
Postoperative VAS pain assessment
VAS
0e10 scale
NRS
0e10 scale
VAS
Not assessed
Not assessed Not assessed
Incision assessment
POSAS
Stony Brook SES
POSAS and NRS
VAS and Singer SES
POSAS
Not specifically POSAS stated and VSS
POSAS
Mackeen. Suture vs staples in cesarean skin closure. Am J Obstet Gynecol 2015.
Telephone interview regarding wound complications
Pfannenstiel
(continued)
ajog.org
Figueroa Sharma et al,16 17 et al, 2014 2013
Obstetrics
Variable
Mackeen et al,5 2014
Research
621.e6 American Journal of Obstetrics & Gynecology MAY 2015
TABLE 1
ajog.org
1995 through 1996 Mackeen. Suture vs staples in cesarean skin closure. Am J Obstet Gynecol 2015.
NRS, numeric rating scale; POSAS, Physician Observer Scar Assessment Scale; SES, scar evaluation scale; VAS, visual analog scale; VSS, Vancouver Scar Scale.
2007 through Started 2003 2008 2009 through 2006 through 2008 through 2010 2008 2009 July through 2009 through 2007 through September 2013 2010 2009 Study length
2010 through 2012
2010 through 2007 through 2011 2008
Women and Infant’s Hospital (United States) University Hospital of Zurich (Switzerland) Addington University of Lehigh Valley Centre Hospital, Insubria (Italy) Health Network Hospitalier University of (United States) Universitaire Kwade Que´bec Zulu-Natal (Canada) (South Africa) University of Spaarne Hospital Copenhagen and Academic (Denmark) Medical Center in Amsterdam (The Netherlands) Study site
University of Alabama (United States) Prasad Government Medical College and Hospital, Kangra (India) Thomas Jefferson University, Lankenau Medical Center, Yale University (United States)
Jeroen Bosch Hospital (The Netherlands)
Assessed based Not assessed on author’s survey tool General satisfaction scale Telephone interview VAS Not assessed Patient Not assessed preference was assessed Subjective
Not assessed Not assessed Subjective Patient satisfaction assessment
Variable
Figueroa et al,16 Sharma 17 et al, 2014 2013 Mackeen et al,5 2014
Study characteristics (continued)
TABLE 1
Aabakke Huppelschoten et al,14 et al,15 2013 2013
de Graaf et al,13 2012
Chunder et al,18 2012
Cromi et al,12 2010
Basha et al,11 2010
Rousseau et al,10 2009
Gaertner et al,9 2008
Frishman et al,8 1997
Obstetrics
Research
were reported by the individual trials. Figure 6 shows the risk of bias assessments for the included studies. In Figure 6, “low risk” (indicated with a green circle with a ‘þ’) indicates: computer-generated or shuffle-cards (randomization), sequentially numbered opaque envelopes (allocation), outcome assessor blinded (blinding of outcome assessment), accounted for lost to follow-up and this was 30% lost to follow-up for their 4-month primary outcome so was listed as high risk of attrition bias. Two studies had >30% lost to follow-up at 6 months12 and 1 year,15 but had low attrition at 4 and 6 week follow-up, respectively; so we determined that other bias was high, but that attrition bias was low. Other bias was listed as unclear for 1 study18 that performed an interim analysis secondary to patients with staples reporting severe discomfort with removal and as high for 1 study11 that stopped early due to the results of an unplanned interim analysis. Supplemental Figure 9 depicts a funnel plot analysis to test for publication bias for the primary outcome of wound complications. As a large number of women were in the symmetrical part of the funnel plot, there was no serious publication bias present.
C OMMENT Our metaanalysis of randomized trials comparing cesarean skin closure with absorbable subcuticular suture vs metal MAY 2015 American Journal of Obstetrics & Gynecology
621.e7
Research
ajog.org
Obstetrics
TABLE 2
Wound complications reported in individual studies Infection
Separation
Hematoma
Seroma
Readmission for wound concern
O
O
O
O
O
O
O
O
No
Figueroa et al, 2013
O
O
O
No
15
O
O
O
No
No
Variable Mackeen et al,5 2014 17
Sharma et al, 2014 16
Huppelschoten et al, 2013
O b
O
b
Aabakke et al, 2013
O
O
No
No
No
de Graaf et al,13 2012
O
O
Oc
O
No
Chunder et al,18 2012
14
O
No
No
No
No
12
O
O
No
No
No
11
O
O
No
No
O
Rousseau et al, 2009
O
No
No
No
No
Gaertner et al,9 2008
O
O
O
O
No
O
O
O
O
Cromi et al, 2010 Basha et al, 2010 10
8
Frishman et al, 1997 a
a
b
No c
Included uterine infections in definition of infection; Hematoma and seroma numbers were not presented separately, but included as causes of skin separation; “Methods” section of study states that this was included as wound complication, however, no information is presented in results regarding this outcome.
Mackeen. Suture vs staples in cesarean skin closure. Am J Obstet Gynecol 2015.
staples favors the use of suture instead of staples to decrease wound morbidity. Wound complications occurred 51% less in patients closed with suture as compared to those closed with staples, and this benefit persisted even when data were stratified into obese and nonobese body mass index. The favorable effect on the wound complication composite was primarily due to a decreased incidence of wound separation in incisions closed with suture, as sutured incisions were 71% less likely to have a wound separation as compared to those closed with staples. Staples were removed between days 3 and 10 across studies (Table 1). Though most studies did not define a length of separation, the 3 largest studies defined separation as: 1 cm,5 as per patient or medical record,11 and as any subcutaneous skin or fascial dehiscence.16 This latter study noted that their results remained significant when defining skin separation as 1 cm.16 In all included studies, it is not clear whether the number of patients reported as having a skin separation had a preceding wound complication, such as a hematoma or seroma, or whether the converse was true. This may be a limitation of
assessing this type of outcome rather than a limitation of these trials. Occurrences of other wound complications such as infection, hematoma, seroma, and readmission, as well as pain perception, patient satisfaction, or cosmesis were not significantly different between the groups. While the choice of suture may have affected outcomes, 8 of the 12 studies (including the largest 3 trials) used monofilament (usually poliglecaprone) suture for closure. Only operating time favored closure with staples. Clay et al19 quoted $8-24/ min in the operating room and since our analysis showed a difference of 7 minutes when suture was used, that is equivalent to an additional $56-168/patient.20 However, a cost analysis must also take into consideration the materials used: metal skin staplers are $7 each ($42/box of 6) and 4-0 poliglecaprone is approximately $4 each (142.43/box of 36). This nominal increase in cost incurred by longer operating time could certainly be offset by the decreased incidence of wound complications in those closed with suture as these complications may necessitate additional office visits, hospital readmission, or treatment with antibiotics.
621.e8 American Journal of Obstetrics & Gynecology MAY 2015
Prior reviews comparing cesarean skin closure with sutures vs staples have been published,3,19,21 but have not included the most recent, large randomized trials.5,14-18 This clinical issue has remained unresolved until now, as evident by a 2011 survey of obstetricians that revealed that their choice for skin incision closure remains divided between suture and staples: 39% preferred absorbable sutures and 48% preferred metal staples.4 Strengths of our metaanalysis include the large number of studies (n ¼ 12) and patients (n ¼ 3112) included. For the first time, recent large studies were included, and this contributed to the ability to individually evaluate 5 different wound complications, but also pain perception, patient satisfaction, cosmesis, and operating time in the same comprehensive and complete review. Data were also analyzed by the subgroup of obese vs nonobese women, making the conclusions even more clinically useful. Not only published, but also unpublished data were sought, obtained, and included. PRISMA guidelines were followed in detail. Obviously, the quality of the metaanalysis rests on
ajog.org
FIGURE 6
Risk of bias within studies
The green circle with ‘þ’ represents low risk. The yellow circle with ‘?’ represents unclear risk. The red circle with ‘-’ represents high risk. Mackeen. Suture vs staples in cesarean skin closure. Am J Obstet Gynecol 2015.
the quality of the 12 included studies: which were of overall high quality (Figure 6). Weaknesses were inherent to weaknesses of the included trials. For example, while wound complications were reported by the vast majority of trials, not all studies reported on pain perception, cosmesis, operating time, or patient satisfaction, making the conclusions regarding these outcomes less reliable. Additionally, the primary outcome differed among studies (Table 1) and many trials focused on cosmesis; though the larger trials primarily assessed wound complications. While we present a composite primary outcome of wound complications, not all of the trials reported on each of the
Obstetrics individual complications included in this composite, so some of the individual outcomes may be underestimated, eg, readmission for wound concern and occurrence of seroma. Statistical heterogeneity was noted in several of the metaanalyses we performed. To account for heterogeneity, we applied random effects analyses and reported Tau2, c2, and I2 statistics where appropriate. We did not note significant publication bias. We assessed for methodology heterogeneity by assessing study quality and risk of bias and overall, the methodology was considered good for included trials. Though overall many of the larger trials were similarly designed, it is possible that clinical heterogeneity accounts for some of the differences noted in the study populations. Two studies were considered at high risk of bias for lack of blinding the (cosmetic) outcome assessment; these were not included in the forest plot analyses of cosmesis (Supplemental Figures 6 and 7), so sensitivity analyses were not indicated. Two of the more recent studies randomized subcuticular closure as well as subcutaneous tissue closure.13,15 It is uncertain how this additional step may have impacted their results, particularly wound separation. However, in the 3 largest studies, the subcutaneous layer was closed if the space was >2 cm.5,11,16 Only 2 of the trials included cesareans performed via vertical skin incisions with a total of 44 women with vertical incisions.11,16 Though these subjects were included in our metaanalysis, given the small number of vertical incisions, we do not believe that our results can be extrapolated to this group of patients. Cesarean is one of the most common surgeries performed worldwide and postoperative wound complications are the most common complications of this surgery.22 Although wound complications such as infection and skin separation are rarely fatal, they incur additional health care cost, additional visits, and possible readmission.23 They may also result in decreased patient satisfaction and increased pain. It is, therefore, crucial to identify the surgical method that will reduce wound complications,
Research
increase efficiency, decrease pain, result in a favorable cosmetic outcome, and improve patient satisfaction. In conclusion, for patients undergoing cesarean delivery, in which speed of closure is not paramount, we recommend closure of the transverse skin incision with suture as this decreases wound morbidity without significantly affecting pain, satisfaction, or cosmesis.ACKNOWLEDGMENTS The authors of this metaanalysis would like to thank the authors of the following RCTs for providing additional information (including unpublished data), for the purpose of this metaanalysis (listed in the order they appear in the paper): Drs Burkhardt,9 Rochon and Smulian,11 Cromi,12 de Graaf,13 Aabakke,14 Huppelschoten,15 and Figueroa and Tita.16 Additionally, the authors would like to thank Kay Johnstone1 (Health Sciences Library Specialist) and Desirae L. Cunningham, MLIS1 (Health Sciences Reference Librarian), who assisted with performing the systematic literature searches and statistician Jocelyn Sendecki, MSPH, for reviewing the statistical analyses.
REFERENCES 1. Dahlke JD, Mendez-Figueroa H, Rouse DJ, Berghella V, Baxter JK, Chauhan SP. Evidencebased surgery for cesarean delivery: an updated systematic review. Am J Obstet Gynecol 2013;209:294-306. 2. Berghella V, Baxter JK, Chauhan SP. Evidence-based surgery for cesarean delivery. Am J Obstet Gynecol 2005;193:1607-17. 3. Mackeen AD, Berghella V, Larsen ML. Techniques and materials for skin closure in cesarean section. Cochrane Database Syst Rev 2012;11:CD003577. 4. Mackeen AD, Devaraj T, Baxter JK. Cesarean skin closure preferences: a survey of obstetricians. J Matern Fetal Neonatal Med 2013;26: 753-6. 5. Mackeen AD, Khalifeh K, Fleisher J, et al. Suture compared with staple skin closure after cesarean delivery: a randomized controlled trial. Obstet Gynecol 2014;123:1169-75. 6. Quinn JV, Drzewiecki AE, Stiell IG, Elmslie TJ. Appearance scales to measure cosmetic outcomes of healed lacerations. Am J Emerg Med 1995;13:229-31. 7. Draaijers LJ, Tempelman FR, Botman YA, et al. The patient and observer scar assessment scale: a reliable and feasible tool for scar evaluation. Plast Reconstr Surg 2004;113:1960-5. 8. Frishman GN, Schwartz T, Hogan JW. Closure of Pfannenstiel skin incisions: staples vs subcuticular suture. J Reprod Med 1997;42: 627-30. 9. Gaertner E, Burkhardt T, Beinder E. Scar appearance of different skin and subcutaneous
MAY 2015 American Journal of Obstetrics & Gynecology
621.e9
Research
ajog.org
Obstetrics
tissue closure techniques in cesarean section: a randomized study. Eur J Obstet Gynecol Reprod Biol 2008;138:29-33. 10. Rousseau JA, Girard K, Turcot-Lemay L, Thomas N. A randomized study comparing skin closure in cesarean sections: staples vs subcuticular sutures. Am J Obstet Gynecol 2009;200:265.e1-4. 11. Basha SL, Rochon ML, Quinones JN, Coassolo KM, Rust OA, Smulian JC. Randomized controlled trial of wound complication rates of subcuticular suture vs staples for skin closure at cesarean delivery. Am J Obstet Gynecol 2010;203:285.e1-8. 12. Cromi A, Ghezzi F, Gottardi A, Cherubino M, Uccella S, Valdatta L. Cosmetic outcomes of various skin closure methods following cesarean delivery: a randomized trial. Am J Obstet Gynecol 2010;203:36.e1-8. 13. de Graaf I, Rengerink KO, Wiersma IC, Donker M, Mol BW, Pajkrt E. Techniques for wound closure at cesarean section: a randomized clinical trial. Eur J Obstet Gynecol Reprod Biol 2012;204(Suppl):S267.
14. Aabakke AJM, Krebs L, Pipper CB, Secher NJ. Subcuticular suture compared with staples for skin closure after cesarean delivery: a randomized controlled trial. Obstet Gynecol 2013;122:878-84. 15. Huppelschoten AG, van Ginderen JC, van den Broek KC, Bouwma AE, Oosterbaan HP. Different ways of subcutaneous tissue and skin closure at cesarean section: a randomized clinical trial on the long-term cosmetic outcome. Acta Obstet Gynecol Scand 2013;92:916-24. 16. Figueroa D, Jauk VC, Szychowski JM, et al. Surgical staples compared with subcuticular suture for skin closure after cesarean delivery: a randomized controlled trial. Obstet Gynecol 2013;121:33-8. 17. Sharma C, Verma A, Soni A, Thusoo M, Mahajan VK, Verma S. A randomized controlled trial comparing cosmetic outcome after skin closure with ’staples’ or ’subcuticular sutures’ in emergency cesarean section. Arch Gynecol Obstet 2014;290:655-9. 18. Chunder A, Devjee J, Khedun SM, Moodley J, Esterhuizen T. A randomized
621.e10 American Journal of Obstetrics & Gynecology MAY 2015
controlled trial on suture materials for skin closure at cesarean section: do wound infection rates differ? S Afr Med J 2012;102: 374-6. 19. Clay FS, Walsh CA, Walsh SR. Staples vs subcuticular sutures for skin closure at cesarean delivery: a metaanalysis of randomized controlled trials. Am J Obstet Gynecol 2011;204:378-83. 20. Singh BI, McGarvey C. Staples for skin closure in surgery. BMJ 2010;340:c403. 21. Tuuli MG, Rampersad RM, Carbone JF, Stamilio D, Macones GA, Odibo AO. Staples compared with subcuticular suture for skin closure after cesarean delivery: a systematic review and meta-analysis. Obstet Gynecol 2011;117:682-90. 22. Hamilton BE, Martin JA, Ventura SJ. Births: preliminary data for 2009. Natl Vital Stat Rep 2010;59:1-19. 23. Reilly J, Twaddle S, McIntosh J, Kean L. An economic analysis of surgical wound infection. J Hosp Infect 2001;49: 245-9.
ajog.org
OBSTETRICS
Suture versus staples for skin closure after cesarean: a metaanalysis Awathif Dhanya Mackeen, MD, MPH; Meike Schuster, DO; Vincenzo Berghella, MD OBJECTIVE: We sought to perform a metaanalysis to synthesize
randomized clinical trials of cesarean skin closure by subcuticular absorbable suture vs metal staples for the outcomes of wound complications, pain perception, patient satisfaction, cosmesis, and operating time. STUDY DESIGN: A systematic search was performed using MEDLINE,
Cochrane Databases, and ClinicalTrials.gov registries. We included randomized trials comparing absorbable suture vs metal staples for cesarean skin closure. Data were abstracted regarding wound complications, patient pain perception, patient satisfaction, cosmesis as assessed by the physician and patient, and operating time. RESULTS: Twelve randomized trials with data for the primary
outcome on 3112 women were identified. Women whose incisions were closed with suture were significantly less likely to have wound complications than those closed with staples (risk ratio, 0.49; 95% confidence interval [CI], 0.28e0.87). This difference remained
significant even when wound complications were stratified by obesity. The decrease in wound complications was largely due to the lower incidence of wound separations in those closed with suture (risk ratio, 0.29; 95% CI, 0.20e0.43), as there were no significant differences in infection, hematoma, seroma, or readmission. There were also no significant differences in pain perception, patient satisfaction, and cosmetic assessments between the groups. Operating time was approximately 7 minutes longer in those closed with suture (95% CI, 3.10e11.31). CONCLUSION: For patients undergoing cesarean, closure of the
transverse skin incision with suture significantly decreases wound morbidity, specifically wound separation, without significant differences in pain, patient satisfaction, or cosmesis. Suture placement does take 7 minutes longer than staples. Key words: cesarean, incision closure, staples, suture, wound complications
Cite this article as: Mackeen AD, Schuster M, Berghella V. Suture versus staples for skin closure after cesarean: a metaanalysis. Am J Obstet Gynecol 2015;212:621.e1-10.
C
esarean is one of the most common surgeries performed worldwide and rates are increasing despite efforts to the contrary.1 Many of the surgical steps have been individually assessed previously, eg, prophylactic antibiotic administration, development of the bladder flap, techniques for expansion of the uterine incision and removal of the placenta, closure of the uterine and fascial incisions, closure of the
subcutaneous space when 2 cm, and closure of the skin incision.1,2 Our previous systematic review as well as Dahlke et al1 concluded that the data remain conflicting with regards to whether it is better to close the cesarean skin incision with suture or with staples.3 Though optimizing the individual steps of a cesarean is important with respect to providing the best possible care for patients, the skin incision is the
From the Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Geisinger Medical Center, Danville (Drs Mackeen and Schuster), and Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia (Dr Berghella), PA. Received Aug. 25, 2014; revised Nov. 18, 2014; accepted Dec. 15, 2014. One of the trials included in this metaanalysis, for which A.D.M. and V.B. are authors, was supported by Ethicon Inc. After that study was designed and initiated, Ethicon Inc agreed to provide funds to assist with patient recruitment and follow-up. The funding source had no influence on study design, study execution, data analysis, or publication. Those funds were not used to support this metaanalysis. The authors report no conflict of interest. Corresponding author: Awathif Dhanya Mackeen, MD, MPH. [email protected] 0002-9378/$36.00 ª 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ajog.2014.12.020
visible reminder to a patient about her cesarean. Despite the potential complexity of the surgery, the occurrence of a wound complication may be the aspect that the patient most clearly recalls. In addition, wound complications may result in prolonged hospital stay, readmission, increased time away from work, decreased infant bonding time, and increased health care expenditures. Choice of closure continues to vary among clinicians, most commonly between absorbable subcuticular suture and nonabsorbable metal staples.4 Additional evidence, including a trial recently published by 2 authors of this metaanalysis, has emerged regarding the optimal closure of the cesarean skin incision.5 As such our goal was to examine the pertinent randomized clinical trials (RCTs) to evaluate the incidence of wound complications, pain perception, patient satisfaction, cosmesis, and operating time when the cesarean skin incision was closed with suture vs with staples.
MAY 2015 American Journal of Obstetrics & Gynecology
621.e1
Research M ATERIALS
AND
ajog.org
Obstetrics M ETHODS
Sources The principles embodied in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement were used in compiling this metaanalysis.5 MEDLINE via Ovid and PubMed searches were performed in July 2014 to encompass the past 50 years of trials; additionally the Cochrane Databases were searched and clinical trials were identified using Ovid and Clinical Key and by searching ClinicalTrials.gov. Ovid MEDLINE was searched using Medical Subject Headings (MeSH) without restrictions for text words or word variations for the following search terms: “cesarean,” “caesarean,” “suture,” “suture techniques,” “stitches,” “staple,” “surgical stapling,” “skin,” “closure,” “wound complications,” “wound infection,” “wound healing,” “wound closure,” “cicatrix,” “scar,” “randomized controlled trial,” and “randomized clinical trial.” “Humans” was set as the only limit. A second search was conducted in PubMed to identify nonindexed citations using the search terms “caesarean,” “cesarean,” “skin,” “wound complications,” “wound healing,” “wound infection,” “surgical wound infection,” “staple,” “suture,” “stitches,” and “trial.” There were no language restrictions applied. Searches were performed by a health sciences library specialist, a reference librarian, and the primary author (A.D.M.). This search was conducted as a brand new search and not part of the original Cochrane review or RCT by this author. As this is a metaanalysis, it was considered exempt from institutional review board approval. Study selection All identified abstracts were independently reviewed by the primary author (A.D.M.) and an additional author (V.B. or M.S.) and full articles were retrieved and reviewed for trials considered for inclusion. The primary author and additional author independently reviewed the manuscripts to assess for inclusion or exclusion criteria for this metaanalysis. We included only RCTs comparing subcuticular absorbable
suture with nonabsorbable metal staples for cesarean skin closure. We chose to exclude RCTs that compared absorbable staples, nonabsorbable suture, or stapling devices (Figure 1). We excluded ongoing trials; studies that assessed surgical techniques for cesarean, but not the skin incision; and studies that did not provide applicable data for inclusion in the metaanalysis (eg, abstracts that did not report sample size).
Study outcomes The primary outcome was wound complications. This was defined as a composite of wound infection, separation, hematoma, seroma, or readmission secondary to a wound concern. These were defined as per the individual trials. Secondary outcomes were patient pain perception at discharge, patient satisfaction at 2 months postoperatively, cosmesis as assessed by the physician and patient at 2 months postoperatively, and operative time. Patient pain perception and satisfaction were collated among studies if a 10-point scale was used, typically the visual analog scale in which higher scores represent higher patient satisfaction and more pain.6 Cosmesis was assessed if studies used the validated Physician Observer Scar Assessment Scale (OSAS) for assessment; this scale has both subjective (Physician Scar Assessment Scale [PSAS]) and objective (OSAS) components as scored by the patient and physician, respectively.7 Patient assessment of cosmesis (PSAS) was scored from 6-60 and physician assessment of cosmesis (OSAS) was scored from 5-50: lower scores are considered superior. When applicable, attempts were made to contact authors to obtain more detail on outcomes not clearly reported in the manuscript. Additionally we analyzed the primary outcome stratified by body mass index (2 cm
50/50
If >2.5 cm
50/50
Not stated
If 2 cm
If >2 cm
100%
50/50
None
Staple removal day
6
3e4 for 4 Pfannenstiel; 7e10 for vertical
3
7
10
7
3e4
3
6
At discharge
2e4 wk
6 wk
4 mo
6 wk
0e10 scale
Assessed based on author’s survey tool
10-cm Pain scale
Singer SES
Cosmesis based on author’s assessment scale
Subjective
4e10
398
Postoperative 4e8 wk follow-up for wound complications
Unclear, but it 4e6 wk appears this was performed at day 3 and at 6 wk
6 wk
3 mo
Unclear at what point these were assessed
Day 1, 3, and 10
2 mo
Postoperative VAS pain assessment
VAS
0e10 scale
NRS
0e10 scale
VAS
Not assessed
Not assessed Not assessed
Incision assessment
POSAS
Stony Brook SES
POSAS and NRS
VAS and Singer SES
POSAS
Not specifically POSAS stated and VSS
POSAS
Mackeen. Suture vs staples in cesarean skin closure. Am J Obstet Gynecol 2015.
Telephone interview regarding wound complications
Pfannenstiel
(continued)
ajog.org
Figueroa Sharma et al,16 17 et al, 2014 2013
Obstetrics
Variable
Mackeen et al,5 2014
Research
621.e6 American Journal of Obstetrics & Gynecology MAY 2015
TABLE 1
ajog.org
1995 through 1996 Mackeen. Suture vs staples in cesarean skin closure. Am J Obstet Gynecol 2015.
NRS, numeric rating scale; POSAS, Physician Observer Scar Assessment Scale; SES, scar evaluation scale; VAS, visual analog scale; VSS, Vancouver Scar Scale.
2007 through Started 2003 2008 2009 through 2006 through 2008 through 2010 2008 2009 July through 2009 through 2007 through September 2013 2010 2009 Study length
2010 through 2012
2010 through 2007 through 2011 2008
Women and Infant’s Hospital (United States) University Hospital of Zurich (Switzerland) Addington University of Lehigh Valley Centre Hospital, Insubria (Italy) Health Network Hospitalier University of (United States) Universitaire Kwade Que´bec Zulu-Natal (Canada) (South Africa) University of Spaarne Hospital Copenhagen and Academic (Denmark) Medical Center in Amsterdam (The Netherlands) Study site
University of Alabama (United States) Prasad Government Medical College and Hospital, Kangra (India) Thomas Jefferson University, Lankenau Medical Center, Yale University (United States)
Jeroen Bosch Hospital (The Netherlands)
Assessed based Not assessed on author’s survey tool General satisfaction scale Telephone interview VAS Not assessed Patient Not assessed preference was assessed Subjective
Not assessed Not assessed Subjective Patient satisfaction assessment
Variable
Figueroa et al,16 Sharma 17 et al, 2014 2013 Mackeen et al,5 2014
Study characteristics (continued)
TABLE 1
Aabakke Huppelschoten et al,14 et al,15 2013 2013
de Graaf et al,13 2012
Chunder et al,18 2012
Cromi et al,12 2010
Basha et al,11 2010
Rousseau et al,10 2009
Gaertner et al,9 2008
Frishman et al,8 1997
Obstetrics
Research
were reported by the individual trials. Figure 6 shows the risk of bias assessments for the included studies. In Figure 6, “low risk” (indicated with a green circle with a ‘þ’) indicates: computer-generated or shuffle-cards (randomization), sequentially numbered opaque envelopes (allocation), outcome assessor blinded (blinding of outcome assessment), accounted for lost to follow-up and this was 30% lost to follow-up for their 4-month primary outcome so was listed as high risk of attrition bias. Two studies had >30% lost to follow-up at 6 months12 and 1 year,15 but had low attrition at 4 and 6 week follow-up, respectively; so we determined that other bias was high, but that attrition bias was low. Other bias was listed as unclear for 1 study18 that performed an interim analysis secondary to patients with staples reporting severe discomfort with removal and as high for 1 study11 that stopped early due to the results of an unplanned interim analysis. Supplemental Figure 9 depicts a funnel plot analysis to test for publication bias for the primary outcome of wound complications. As a large number of women were in the symmetrical part of the funnel plot, there was no serious publication bias present.
C OMMENT Our metaanalysis of randomized trials comparing cesarean skin closure with absorbable subcuticular suture vs metal MAY 2015 American Journal of Obstetrics & Gynecology
621.e7
Research
ajog.org
Obstetrics
TABLE 2
Wound complications reported in individual studies Infection
Separation
Hematoma
Seroma
Readmission for wound concern
O
O
O
O
O
O
O
O
No
Figueroa et al, 2013
O
O
O
No
15
O
O
O
No
No
Variable Mackeen et al,5 2014 17
Sharma et al, 2014 16
Huppelschoten et al, 2013
O b
O
b
Aabakke et al, 2013
O
O
No
No
No
de Graaf et al,13 2012
O
O
Oc
O
No
Chunder et al,18 2012
14
O
No
No
No
No
12
O
O
No
No
No
11
O
O
No
No
O
Rousseau et al, 2009
O
No
No
No
No
Gaertner et al,9 2008
O
O
O
O
No
O
O
O
O
Cromi et al, 2010 Basha et al, 2010 10
8
Frishman et al, 1997 a
a
b
No c
Included uterine infections in definition of infection; Hematoma and seroma numbers were not presented separately, but included as causes of skin separation; “Methods” section of study states that this was included as wound complication, however, no information is presented in results regarding this outcome.
Mackeen. Suture vs staples in cesarean skin closure. Am J Obstet Gynecol 2015.
staples favors the use of suture instead of staples to decrease wound morbidity. Wound complications occurred 51% less in patients closed with suture as compared to those closed with staples, and this benefit persisted even when data were stratified into obese and nonobese body mass index. The favorable effect on the wound complication composite was primarily due to a decreased incidence of wound separation in incisions closed with suture, as sutured incisions were 71% less likely to have a wound separation as compared to those closed with staples. Staples were removed between days 3 and 10 across studies (Table 1). Though most studies did not define a length of separation, the 3 largest studies defined separation as: 1 cm,5 as per patient or medical record,11 and as any subcutaneous skin or fascial dehiscence.16 This latter study noted that their results remained significant when defining skin separation as 1 cm.16 In all included studies, it is not clear whether the number of patients reported as having a skin separation had a preceding wound complication, such as a hematoma or seroma, or whether the converse was true. This may be a limitation of
assessing this type of outcome rather than a limitation of these trials. Occurrences of other wound complications such as infection, hematoma, seroma, and readmission, as well as pain perception, patient satisfaction, or cosmesis were not significantly different between the groups. While the choice of suture may have affected outcomes, 8 of the 12 studies (including the largest 3 trials) used monofilament (usually poliglecaprone) suture for closure. Only operating time favored closure with staples. Clay et al19 quoted $8-24/ min in the operating room and since our analysis showed a difference of 7 minutes when suture was used, that is equivalent to an additional $56-168/patient.20 However, a cost analysis must also take into consideration the materials used: metal skin staplers are $7 each ($42/box of 6) and 4-0 poliglecaprone is approximately $4 each (142.43/box of 36). This nominal increase in cost incurred by longer operating time could certainly be offset by the decreased incidence of wound complications in those closed with suture as these complications may necessitate additional office visits, hospital readmission, or treatment with antibiotics.
621.e8 American Journal of Obstetrics & Gynecology MAY 2015
Prior reviews comparing cesarean skin closure with sutures vs staples have been published,3,19,21 but have not included the most recent, large randomized trials.5,14-18 This clinical issue has remained unresolved until now, as evident by a 2011 survey of obstetricians that revealed that their choice for skin incision closure remains divided between suture and staples: 39% preferred absorbable sutures and 48% preferred metal staples.4 Strengths of our metaanalysis include the large number of studies (n ¼ 12) and patients (n ¼ 3112) included. For the first time, recent large studies were included, and this contributed to the ability to individually evaluate 5 different wound complications, but also pain perception, patient satisfaction, cosmesis, and operating time in the same comprehensive and complete review. Data were also analyzed by the subgroup of obese vs nonobese women, making the conclusions even more clinically useful. Not only published, but also unpublished data were sought, obtained, and included. PRISMA guidelines were followed in detail. Obviously, the quality of the metaanalysis rests on
ajog.org
FIGURE 6
Risk of bias within studies
The green circle with ‘þ’ represents low risk. The yellow circle with ‘?’ represents unclear risk. The red circle with ‘-’ represents high risk. Mackeen. Suture vs staples in cesarean skin closure. Am J Obstet Gynecol 2015.
the quality of the 12 included studies: which were of overall high quality (Figure 6). Weaknesses were inherent to weaknesses of the included trials. For example, while wound complications were reported by the vast majority of trials, not all studies reported on pain perception, cosmesis, operating time, or patient satisfaction, making the conclusions regarding these outcomes less reliable. Additionally, the primary outcome differed among studies (Table 1) and many trials focused on cosmesis; though the larger trials primarily assessed wound complications. While we present a composite primary outcome of wound complications, not all of the trials reported on each of the
Obstetrics individual complications included in this composite, so some of the individual outcomes may be underestimated, eg, readmission for wound concern and occurrence of seroma. Statistical heterogeneity was noted in several of the metaanalyses we performed. To account for heterogeneity, we applied random effects analyses and reported Tau2, c2, and I2 statistics where appropriate. We did not note significant publication bias. We assessed for methodology heterogeneity by assessing study quality and risk of bias and overall, the methodology was considered good for included trials. Though overall many of the larger trials were similarly designed, it is possible that clinical heterogeneity accounts for some of the differences noted in the study populations. Two studies were considered at high risk of bias for lack of blinding the (cosmetic) outcome assessment; these were not included in the forest plot analyses of cosmesis (Supplemental Figures 6 and 7), so sensitivity analyses were not indicated. Two of the more recent studies randomized subcuticular closure as well as subcutaneous tissue closure.13,15 It is uncertain how this additional step may have impacted their results, particularly wound separation. However, in the 3 largest studies, the subcutaneous layer was closed if the space was >2 cm.5,11,16 Only 2 of the trials included cesareans performed via vertical skin incisions with a total of 44 women with vertical incisions.11,16 Though these subjects were included in our metaanalysis, given the small number of vertical incisions, we do not believe that our results can be extrapolated to this group of patients. Cesarean is one of the most common surgeries performed worldwide and postoperative wound complications are the most common complications of this surgery.22 Although wound complications such as infection and skin separation are rarely fatal, they incur additional health care cost, additional visits, and possible readmission.23 They may also result in decreased patient satisfaction and increased pain. It is, therefore, crucial to identify the surgical method that will reduce wound complications,
Research
increase efficiency, decrease pain, result in a favorable cosmetic outcome, and improve patient satisfaction. In conclusion, for patients undergoing cesarean delivery, in which speed of closure is not paramount, we recommend closure of the transverse skin incision with suture as this decreases wound morbidity without significantly affecting pain, satisfaction, or cosmesis.ACKNOWLEDGMENTS The authors of this metaanalysis would like to thank the authors of the following RCTs for providing additional information (including unpublished data), for the purpose of this metaanalysis (listed in the order they appear in the paper): Drs Burkhardt,9 Rochon and Smulian,11 Cromi,12 de Graaf,13 Aabakke,14 Huppelschoten,15 and Figueroa and Tita.16 Additionally, the authors would like to thank Kay Johnstone1 (Health Sciences Library Specialist) and Desirae L. Cunningham, MLIS1 (Health Sciences Reference Librarian), who assisted with performing the systematic literature searches and statistician Jocelyn Sendecki, MSPH, for reviewing the statistical analyses.
REFERENCES 1. Dahlke JD, Mendez-Figueroa H, Rouse DJ, Berghella V, Baxter JK, Chauhan SP. Evidencebased surgery for cesarean delivery: an updated systematic review. Am J Obstet Gynecol 2013;209:294-306. 2. Berghella V, Baxter JK, Chauhan SP. Evidence-based surgery for cesarean delivery. Am J Obstet Gynecol 2005;193:1607-17. 3. Mackeen AD, Berghella V, Larsen ML. Techniques and materials for skin closure in cesarean section. Cochrane Database Syst Rev 2012;11:CD003577. 4. Mackeen AD, Devaraj T, Baxter JK. Cesarean skin closure preferences: a survey of obstetricians. J Matern Fetal Neonatal Med 2013;26: 753-6. 5. Mackeen AD, Khalifeh K, Fleisher J, et al. Suture compared with staple skin closure after cesarean delivery: a randomized controlled trial. Obstet Gynecol 2014;123:1169-75. 6. Quinn JV, Drzewiecki AE, Stiell IG, Elmslie TJ. Appearance scales to measure cosmetic outcomes of healed lacerations. Am J Emerg Med 1995;13:229-31. 7. Draaijers LJ, Tempelman FR, Botman YA, et al. The patient and observer scar assessment scale: a reliable and feasible tool for scar evaluation. Plast Reconstr Surg 2004;113:1960-5. 8. Frishman GN, Schwartz T, Hogan JW. Closure of Pfannenstiel skin incisions: staples vs subcuticular suture. J Reprod Med 1997;42: 627-30. 9. Gaertner E, Burkhardt T, Beinder E. Scar appearance of different skin and subcutaneous
MAY 2015 American Journal of Obstetrics & Gynecology
621.e9
Research
ajog.org
Obstetrics
tissue closure techniques in cesarean section: a randomized study. Eur J Obstet Gynecol Reprod Biol 2008;138:29-33. 10. Rousseau JA, Girard K, Turcot-Lemay L, Thomas N. A randomized study comparing skin closure in cesarean sections: staples vs subcuticular sutures. Am J Obstet Gynecol 2009;200:265.e1-4. 11. Basha SL, Rochon ML, Quinones JN, Coassolo KM, Rust OA, Smulian JC. Randomized controlled trial of wound complication rates of subcuticular suture vs staples for skin closure at cesarean delivery. Am J Obstet Gynecol 2010;203:285.e1-8. 12. Cromi A, Ghezzi F, Gottardi A, Cherubino M, Uccella S, Valdatta L. Cosmetic outcomes of various skin closure methods following cesarean delivery: a randomized trial. Am J Obstet Gynecol 2010;203:36.e1-8. 13. de Graaf I, Rengerink KO, Wiersma IC, Donker M, Mol BW, Pajkrt E. Techniques for wound closure at cesarean section: a randomized clinical trial. Eur J Obstet Gynecol Reprod Biol 2012;204(Suppl):S267.
14. Aabakke AJM, Krebs L, Pipper CB, Secher NJ. Subcuticular suture compared with staples for skin closure after cesarean delivery: a randomized controlled trial. Obstet Gynecol 2013;122:878-84. 15. Huppelschoten AG, van Ginderen JC, van den Broek KC, Bouwma AE, Oosterbaan HP. Different ways of subcutaneous tissue and skin closure at cesarean section: a randomized clinical trial on the long-term cosmetic outcome. Acta Obstet Gynecol Scand 2013;92:916-24. 16. Figueroa D, Jauk VC, Szychowski JM, et al. Surgical staples compared with subcuticular suture for skin closure after cesarean delivery: a randomized controlled trial. Obstet Gynecol 2013;121:33-8. 17. Sharma C, Verma A, Soni A, Thusoo M, Mahajan VK, Verma S. A randomized controlled trial comparing cosmetic outcome after skin closure with ’staples’ or ’subcuticular sutures’ in emergency cesarean section. Arch Gynecol Obstet 2014;290:655-9. 18. Chunder A, Devjee J, Khedun SM, Moodley J, Esterhuizen T. A randomized
621.e10 American Journal of Obstetrics & Gynecology MAY 2015
controlled trial on suture materials for skin closure at cesarean section: do wound infection rates differ? S Afr Med J 2012;102: 374-6. 19. Clay FS, Walsh CA, Walsh SR. Staples vs subcuticular sutures for skin closure at cesarean delivery: a metaanalysis of randomized controlled trials. Am J Obstet Gynecol 2011;204:378-83. 20. Singh BI, McGarvey C. Staples for skin closure in surgery. BMJ 2010;340:c403. 21. Tuuli MG, Rampersad RM, Carbone JF, Stamilio D, Macones GA, Odibo AO. Staples compared with subcuticular suture for skin closure after cesarean delivery: a systematic review and meta-analysis. Obstet Gynecol 2011;117:682-90. 22. Hamilton BE, Martin JA, Ventura SJ. Births: preliminary data for 2009. Natl Vital Stat Rep 2010;59:1-19. 23. Reilly J, Twaddle S, McIntosh J, Kean L. An economic analysis of surgical wound infection. J Hosp Infect 2001;49: 245-9.
