Clinical Science. KEYWORDS: Femoral hernia; Ischemia; Intestinal obstruction; Risk factors

Transcription

1 The American Journal of Surgery (2013) 205, Clinical Science Improved outcomes of incarcerated femoral hernia: a multivariate analysis of predictive factors of bowel ischemia and potential impact on postoperative complications Cristina Alhambra-Rodriguez de Guzmán, M.D. a, Joaquín Picazo-Yeste, M.D., Ph.D. a, *, Jose María Tenías-Burillo, M.D., Ph.D. b, Carlos Moreno-Sanz, M.D., Ph.D. a a Department of General and Digestive Surgery, Hospital General La Mancha, Centro Avenida de la Constitución, Alcázar de San Juan, Ciudad Real, Spain; b Department of Epidemiology and Preventive Medicine, Hospital General La Mancha, Ciuda Real, Spain KEYWORDS: Femoral hernia; Ischemia; Intestinal obstruction; Risk factors Abstract BACKGROUND: Although much of the literature focuses on risk factors for intestinal resection in groin hernias, little is known specifically for the femoral type. This study identifies clinical and analytic parameters associated with intestinal ischemia in patients with an incarcerated femoral hernia. METHODS: Eighty-six patients with an incarcerated femoral hernia were included in an analytic, longitudinal, observational, retrospective cohort study. Clinical presentation, the duration of symptoms, analytic and radiologic studies, complications, and mortality rates were analyzed. RESULTS: Eight (9.3%) patients underwent intestinal resection. Factors related to intestinal ischemia were oral anticoagulants intake (odds ratio 5 9.6) and a duration of symptoms longer than 3 days (odds ratio 5 2.1). There was no relationship between leukocytosis (P 5.02) or radiographic signs of intestinal obstruction (P 5.28) and bowel resection. CONCLUSIONS: Patients with a duration of symptoms longer than 3 days and, interestingly, those having oral anticoagulant therapy appeared to be at a higher risk for developing intestinal ischemia. A remarkable reduction in morbimortality can be achieved through an earlier referral to the hospital, quick preoperative workup, and urgent operation. Ó 2013 Elsevier Inc. All rights reserved. Hernia surgery is one of the most frequently performed operations in the Western world. Despite this universally acknowledged fact, scant attention has been paid to * Corresponding author. Tel.: ; fax: address: salvelio@yahoo.es Manuscript received December 18, 2011; revised manuscript February 2, 2012 the prevalence, resulting disability, recurrence, and socioeconomic implications of hernias. The incidence of femoral hernia is reported to be 2% to 8% of all groin hernias in adult patients. This type of hernia, which is very rare in children, is most commonly observed between the fourth and seventh decades of life and is 4 to 5 times more common in women. In addition, for reasons yet unknown, right-sided presentation is more common than left-sided presentation /$ - see front matter Ó 2013 Elsevier Inc. All rights reserved.

2 C. Alhambra-Rodriguez de Guzmán et al. Outcomes of incarcerated femoral hernia 189 Although the incidence of femoral hernias is low, they are of high clinical importance because they often present with strangulation. The incidence of strangulation reaches 38% in some reports, leading to high morbidity and mortality rates. 1 4 The importance of an early diagnosis of incarceration is paramount because a delay increases the risk of ischemia and necrosis of the incarcerated tissue, thus augmenting the need for intestinal resection with its consequently higher morbidity and mortality rates. 5 7 The only satisfactory treatment for incarcerated femoral hernia is an urgent operation. Over the past several years, many published studies have examined the efficacy of different hernia repair techniques, which have undergone a remarkable evolution with the development of prosthetic materials. Currently, the Lichtenstein femoral plug repair is the most widely used technique. It is reliable, safe, and easily reproducible and has become the gold standard for both elective and emergency hernia repair. Although preperitoneal hernia repair is as reliable and safe as the anterior approach, 8 it requires specific training, and some surgeons find it more difficult to perform. With regard to complications, available studies have found no differences between anterior and preperitoneal techniques with respect to wound infection, seroma formation, or hematomas. 9 Although prostheses are widely used in elective groin hernia repair, the use of synthetic materials is considered controversial in emergency operations because of the inherent risk of sepsis. 10 Moreover, some surgeons consider the presentation of strangulated hernia to be an absolute contraindication for the use of prosthetic meshes because of a higher risk of infection. 11 However, others such as Pans et al 12 consider the risk of sepsis to be overestimated. They insist that with careful attention to local antisepsis and the use of systemic antibiotic therapy there should be no additional risk of local infection when inserting a prosthesis during an emergency herniorraphy procedure Late admission to the hospital is perhaps the most important factor in the evolution of an incarcerated femoral hernia because the prolonged duration of symptoms leads to a higher risk of intestinal ischemia and necrosis of the incarcerated tissue. Some reports show that bowel obstruction significantly increases the mortality rates associated with hernias. Several studies have analyzed the risk factors for intestinal resection in groin hernias but not specifically for the femoral type. Our special concern regarding abdominal wall pathology led us to develop and maintain a reliable database during the last 16 years. The awareness of a surprisingly low rate of bowel resection made us investigate this issue. As far as we know, this article reports on one of the largest single-institution series dealing with incarcerated femoral hernias. To anticipate bowel necrosis and its catastrophic consequences, we investigated the relationship between several preoperative clinical, radiologic, and laboratory findings and the occurrence of irreversible ischemia in incarcerated femoral hernias. This article also focuses on potential strategies aiming to achieve the best control of intestinal viability upfront bowel necrosis. Methods Study design and patients We conducted an analytic, longitudinal, observational, retrospective cohort study with 86 adult patients undergoing emergency treatment for incarcerated femoral hernias at La Mancha Centro General Hospital, Ciudad Real, Spain, between 1995 and All patients underwent a routine preoperative workup including blood analysis, an electrocardiogram, chest and abdominal radiographs, and anesthesiology consulting. Because incarcerated femoral hernia is mainly determined by a clinical diagnosis, other radiologic studies (ie, ultrasonography, a computed tomography scan, and magnetic resonance imaging) were deemed unnecessary. Attempts for the manual reduction of femoral hernias are forbidden in our hospital. A hematologist was consulted for patients on anticoagulant therapy, proceeding for immediate reversal (ie, vitamin K, plasma infusion, and/ or activated prothrombin complex). All operations were performed as soon as possible once the patient was prepared for surgery. Depending on the surgical team preference, the anterior or preperitoneal approach was used. The following patient information was recorded: sex, age, personal health history, a history of cardiopulmonary diseases, a history of intake of oral anticoagulants, the presence of diabetes mellitus, clinical presentation (ie, tumor, pain, nausea and vomiting, and fever), time until the operation, laboratory results (ie, white cell blood count), radiologic studies (ie, signs of bowel obstruction), postoperative medical complications (ie, heart failure and pneumonia), wound infection and the presence of fistula, the surgical technique used (anterior vs preperitoneal approach), the length of hospital stay, and mortality. Analysis All continuous data were expressed with central tendency measures as means and dispersion measures as standard deviations. Qualitative data are expressed as absolute and relative frequencies (percentages). Statistical analyses were performed using either the t test, chi-square test, or Fisher exact test. Differences were considered to be significant at P,.05. To identify predictive factors for bowel resection caused by ischemia, a predictive model was created with the aid of multiple logistic regression analysis. The dependent variable was the presence or absence of bowel ischemia. First, we performed a simple logistic regression to determine the relationship between each potential predictor variable with bowel resection caused by ischemia. Those variables with a P value %.25 were selected for the multiple logistic regression analysis. The Hosmer-Lemeshow test was performed for internal calibration of the model. The capability of discrimination of the model was calculated by the area under the receiver operating characteristic curve. All analyses were

3 190 The American Journal of Surgery, Vol 205, No 2, February 2013 performed with SPSS software (version 18.0; SPSS Inc, Chicago, IL). Results During the study period, a total of 86 adults with incarcerated femoral hernias were included in the analysis, 20 men (23.3%) and 66 women (76.7%). The average age of the patients was years (range 27.6 to 93.9 years). Twenty-nine (33.7%) patients suffered from cardiopulmonary disease; 4 (4.7%) had diabetes mellitus; and 10 (11.6%) patients were taking oral anticoagulants for the treatment of atrial fibrillation (7 cases), previous deep venous thrombosis (2 cases), and dilated cardiomyopathy (1 case). The most common complaint was pain in 77 cases (89.5%) followed by the presence of a femoral bulge in 64 cases (74.4%), nausea and vomiting in 44 cases (51.2%), and fever in 2 patients (2.3%). Leukocytosis above 11,000 was present in 31 cases (36%), and radiographic signs of bowel obstruction were observed in 37 patients (43%). In all 86 cases, the repair was buttressed with a polypropylene mesh. Forty-six cases (53.5%) were operated using the anterior approach (ie, placing a plug into the Table 1 Variables Characteristics of patients with and without bowel resection Total (N 5 86) No bowel resection (N 5 78) Bowel resection (N 5 8) P value Sex (%) Male 20 (23.3) 17 (21.8) 3 (37.5).38 Female 66 (76.7) 61 (78.2) 5 (62.5) Age (y) Duration of symptoms Concomitant disease (%) Without 56 (65.1) 53 (67.9) 3 (37.5).121 With 30 (34.9) 25 (32.1) 5 (62.5) Cardiopulmonary diseases (%) Without 57 (62.3) 52 (66.7) 5 (62.5) 1 With 29 (33.7) 26 (33.3) 3 (37.5) Anticoagulants oral (%) Without 76 (88.4) 71 (91.1) 5 (62.5).047 With 10 (11.6) 7 (8.9) 3 (37.5) Diabetes mellitus (%) Without 82 (95.3) 74 (94.9) 8 (100) 1 With 4 (4.7) 4 (5.1) 0 (0) Femoral tumor (%) Without 22 (25.6) 21 (26.9) 1 (12.5).674 With 64 (74.4) 57 (73.1) 7 (87.5) Pain (%) Without 9 (10.5) 7 (8.9) 2 (25).196 With 77 (89.5) 71 (91.1) 6 (75) Nausea and vomiting (%) Without 42 (48.8) 40 (51.3) 2 (25).266 With 44 (51.2) 38 (48.7) 6 (75) Fever (%) Without 84 (97.7) 78 (100) 6 (75).008 With 2 (2.3) 0 (0) 2 (25) Signs of bowel obstruction at abdomen radiography (%) Without 49 (56.9) 46 (58.9) 3 (37.5).282 With 37 (43.1) 32 (41.1) 5 (62.5) Leukocytosis* (%) Without 55 (63.9) 53 (67.9) 2 (25).023 With 31 (36.1) 25 (32.1) 6 (75) Length of stay (d) ,.001 Surgical technique (%) Anterior 46 (53.5) 44 (56.4) 2 (25).138 Preperitoneal 40 (46.5) 34 (43.6) 6 (75) *The presence of leukocytosis: values above 11,000; absence: values below 11,000. The Fisher exact test. t test for independent samples.

4 C. Alhambra-Rodriguez de Guzmán et al. Outcomes of incarcerated femoral hernia 191 Table 2 The duration of symptoms of patients at the moment of hospital admission Duration of symptoms Total (N 5 86) No bowel resection (N 5 78) (%) Bowel resection (N 5 8) (%) P value* %3 days (94.5) 4 (5.5) days 13 9 (69.2) 4 (30.8) *The Fisher exact test was used unless otherwise indicated. femoral ring), whereas 40 patients (46.5%) underwent a modified open preperitoneal hernioplasty as previously described by our group. 8 Briefly, the procedure consists of an open preperitoneal approach (ie, the Nyhus approach) to insert a patch of polypropylene individually fashioned in an approximately 12! 10 cm M -shaped piece to conform to each patient s anatomy and placed without fixation and covering all potential hernial orifices. The aim here is to create 3 prolongations (flaps) in the mesh for proper self-anchorage in the preperitoneal space. Because the spermatic cord is parietalized under the central flap, a slit in the prosthesis is unnecessary, thus avoiding its weakening. Bowel resection because of ischemia was required in 8 cases (9.3%). Demographic and clinical characteristics of patients with or without bowel resection are given in Table 1. Patients who required bowel resection were older ( vs years, P 5.24) and had a longer hospital stay (13.3 vs 4.8 days, P,.001). Seventy-three (85%) of the 86 patients were admitted to the hospital within the first 3 days after the onset of symptoms. The duration of symptoms was longer in patients who required bowel resection ( vs days, P 5.02) with a significant cutoff point at 3 days (Table 2). A multivariable logistic regression model identified 2 variables that were independent risk factors for bowel resection because of ischemia (Table 3): oral anticoagulants intake (odds ratio [95% confidence interval, 1.5 to 60.8], P 5.016) and a duration of symptoms.3 days (odds ratio [95% confidence interval, 1.1 to 3.7], P 5.015). Patients whose blood analysis showed over 11,000 leukocytes presented almost a 3-fold risk of bowel resection because of ischemia compared with those with lower values although the difference was not statistically significant (P 5.176). Two patients had fever; both belonged to the group requiring bowel resection because of ischemia (P 5.008). Severe postoperative complications are listed in Table 4. Bowel resection was associated with a higher likelihood of complications, including both medical condition and Table 3 Risk factors for bowel resection because of ischemia Risk factors P value OR (95% CI)* Duration of symptoms.3 days ( ) Oral anticoagulants ( ) CI 5 confidence interval; OR 5 odds ratio. *Odds ratio derived from logistic regression; values in parentheses are 95% confidence intervals. wound infection. There were 9 complications (10.5%); 2 patients developed pneumonia, and 7 presented with wound infection (62.5% vs 5.1%, P,.001). In 6 (86%) of 7 complicated wounds, the infections were located in the superficial site, and all healed with conservative treatment. The only patient with deep site infection (she had received a Lichtenstein plug repair with bowel resection through the femoral canal) developed a chronic cutaneous fistula. She was scheduled for removal of the plug 6 months after the first operation. The inguinofemoral area was reinforced with a new preperitoneal mesh with an uneventful recovery. Fifty percent of patients who underwent bowel resection developed wound infection, whereas this complication arose in only 3.8% of cases with no bowel resection. Two patients died, accounting for a global mortality rate of 2.3%. Both patients belonged to the bowel resection group (P 5.008). Indeed, mortality and general complications were both significantly associated with bowel resection. Comments Our results indicate 2 independent risk factors for bowel resection in patients with incarcerated femoral hernia. First, patients taking oral anticoagulants have a much higher risk of having bowel ischemia. Although it is not easy to find a physiopathological reason for this association, we suggest that patients receiving these medications may have some underlying disease that predisposes them to bowel ischemia. If this hypothesis is considered plausible, it raises serious doubts about the opinion that anticoagulant therapies may protect against ischemic complications. Moreover, reversion of anticoagulant effects before surgery should be undertaken as quickly as possible. Considering that our favorable results may be related to this way of proceeding, we should emphasize the role of operating as soon as possible, even more in the presence of anticoagulant therapy. In our experience, this management has led us to frequently find cyanotic but viable intestinal loops within the hernia sac. Second, we found a relationship between the prolonged duration of symptoms (.3 days) up to the time of surgery and a higher risk of bowel resection, which is consistent with the findings reported by Kurt et al. 16 Being female and/or being over the age of 65 years have been reported by several authors to be risk factors for incarcerated femoral hernia, 16,17 but our study found no evidence of this. Ge et al 18 retrospectively analyzed 182 patients who had undergone emergency surgery for incarcerated groin hernia,

5 192 The American Journal of Surgery, Vol 205, No 2, February 2013 Table 4 Postoperative complications of patients with and without bowel resection Variable Total (N 5 86) No bowel resection (N 5 78) Bowel resection (N 5 8) P value* General complications (%) Without 77 (89.5) 74 (94.9) 3 (37.5),.001 With 9 (10.5) 4 (5.1) 5 (62.5) Pneumonia (%) Without 84 (97.7) 77 (98.7) 7 (87.5).18 With 2 (2.3) 1 (1.3) 1 (12.5) Wound infection (%)) Without 79 (91.9) 75 (96.2) 4 (50).001 With 7 (8.1) 3 (3.8) 4 (50) Mortality (%) Without 84 (97.7) 78 (100) 6 (75).008 With 2 (2.3) 0 (0) 2 (25) *The Fisher exact test was used unless indicated otherwise. 28 of them with the femoral type. They observed a rate of bowel resection for femoral hernias of approximately 46%. This resection rate, the highest we have found in the literature, is consistent with several other reports 3,6,16 19 in which the rate ranges from 20.8% to 38.5%. In contrast, our study showed a significantly lower resection rate of only 9.3% (Table 5). This marked difference must be highlighted because it raises doubts about previously asserted associations. In our series, 73 (85%) patients experienced a duration of symptoms of 3 days or less before seeking specialized medical help, perhaps because of quick referrals on the part of their general practitioners. This suggests that minimizing the preoperative period in patients with incarcerated femoral hernias may be a way to lower bowel resection rates. The development of bowel necrosis and subsequent bowel resection has been associated with longer hospital stays and worse outcomes for patients with incarcerated femoral hernia; indeed, some studies have shown that bowel resection has a direct effect on morbidity and mortality. 5 This supposition is confirmed in our study because patients who underwent bowel resection had longer postoperative hospital stays, mainly because of surgical wound infections. Moreover, we observed a mortality rate of 25% after bowel resection, which is higher than the results published by Kulah et al 19 (17.6%) although the differences are not statistically significant (P 5.91). Suppiah et al 17 found morbidity and mortality rates of 21.4% and a 3.6%, respectively, after emergency or elective femoral hernia surgery, both of which exceed the rates observed in our study. Alterations in skin color and the presence of leukocytosis are usually considered to be signs of strangulated femoral hernia. However, we were not able to show an association between leukocytosis and bowel ischemia in our study. Although there was a clearly higher rate of bowel resection in patients with leukocyte values above 11,000, this association was not found to be statistically significant. 12 Our data likewise showed no association between the suspicion of intestinal obstruction as seen in abdominal radiography and bowel ischemia. This is consistent with observations made by Sarr et al, 20 who found no preoperative clinical parameters including the presence of continuous abdominal pain, fever, peritoneal signs, leukocytosis, or acidosis, or a combination thereof, proved to be sensitive, specific, and predictive for strangulation. The principal limitation of our study is its retrospective nature, and further prospective studies are needed for a better assessment of the proposed risk factors. However, some of the key issues discussed in this article may be integrated into Table 5 Literature reports of bowel resection and mortality in femoral hernia and comparison with this study Reference Study period Patients with emergency femoral hernia Resection rate (%) P value* Mortality rate (%) P value Álvarez et al (20.8) (3.9).9 Derici et al (21).3 1 (5.3).95 Kurt et al (38.5).014 d d Suppiah et al (28.6) (3.6).75 Ge et al (46.4),.001 d d Kulah et al (41) (7).4 This study (9.3) d 2 (2.3) d *P value: result of the comparison of the resection rate between this study and the rest. P value: result of the comparison of the mortality rate between this study and the rest.

6 C. Alhambra-Rodriguez de Guzmán et al. Outcomes of incarcerated femoral hernia 193 a strategy to achieve the highest advance before the development of irreversible bowel necrosis. In that sense, we should underline the following: improving the level of suspicion of incarcerated femoral hernia at primary care providers (maybe through specific medical instruction); stating clearly that any attempt of manual hernia reduction should be avoided at all levels of health care (ie, general practitioners, emergency room staff members, residents, and surgeons) when a femoral hernia is suspected; and preparing the patients for surgery as soon as possible, especially if they are receiving anticoagulant therapy or we think that the duration of symptoms is about 3 days or more. Conclusions Similar to previously published results, our study found that physical signs, leukocytosis, and radiologic data of intestinal obstruction are not useful for anticipating intestinal ischemia. Our main finding was that there is a strong association between the intake of oral anticoagulants and the prolonged duration of symptoms in patients with incarcerated femoral hernia and the presence of bowel necrosis. In these circumstances, a prompt operation is necessary. We also showed that the average rate of bowel resection among patients with incarcerated femoral hernia can be reduced from those in previously reported series if the aforementioned factors are properly controlled. References 1. Hachisuka T. Femoral hernia repair. Surg Clin N Am 2003;83: Oishi S, Page C, Schwesinger W. Complicated presentations of groin hernias. Am J Surg 1991;162: Álvarez-Pérez JA, Baldonedo-Cernuda RF, García-Bear I, et al. Presentation and clinical evolution of incarcerated groin hernias in adults. Cir Esp 2005;77: Gallegos NC, Dawson J, Jarvis M, et al. Risk of strangulation in groin hernias. Br J Surg 1991;78: Alimoglu O, Kaya B, Okan I, et al. Fermoral hernia: a review of 83 cases. Hernia 2006;10: Derici H, Unalp HR, Bozdag AD, et al. Factors affecting morbidity and mortality in incarcerated abdominal wall hernias. Henia 2007; 11: Chamary VL. Femoral hernia: intestinal obstruction is an unrecognized source of morbidity and mortality. Br J Surg 1993;80: Picazo JS, Seoane JB, Moreno C, et al. Description of M-shaped preperitoneal hernioplasty for inguinocrural hernias. Am J Surg 2003;185: Muldoon RL, Marchant K, Johnson DD, et al. Lichtenstein vs anterior preperitoneal prosthetic mesh placement in open inguinal repair: a prospective, randomized trial. Hernia 2004;8: Campanelli G, Nicolosi FM, Pettinari D, et al. Prosthetic repair, intestinal resection, and potentially contaminated areas: safe and feasible? Hernia 2004;8: Nyhus LM, Pollak R, Bombeck CT, et al. The preperitoneal approach and prosthetic buttress repair for recurrent hernia. The evolution of a technique. Ann Surg 1988;208: Pans A, Desaive C, Jacquet N. Use of preperitoneal prosthesis for strangulated groin hernia. Br J Surg 1997;84: Wysocki A, Kulawik J, Pozniczek M, et al. Is the Lichtenstein operation of strangulated groin hernia a safe procedure? World J Surg 2006; 30: Dahlstrand U, Wollert S, Nordin P, et al. Emergency femoral hernia repair. a study based on a National Register. Ann Surg 2009;249: Karatepe O, Adas G, Battal M, et al. The comparison of preperitoneal and Lichtenstein repair for incarcerated groin hernias: a randomized controlled trial. Int J Surg 2008;6: Kurt N, Oncel M, Ozkan Z, et al. Risk and outcome of bowel resection in patients with incarcerated groin hernias: retrospective study. World J Surg 2003;27: Suppiah A, Gatt M, Barandiaran J, et al. Outcomes of emergency and elective femoral hernia surgery in four district general hospitals: a 4-year study. Hernia 2007;11: Ge BJ, Huang Q, Liu L, et al. Risk factors for bowel resection and outcome in patients with incarcerated groin hernias. Hernia 2010;14: Kulah B, Duzgun AP, Moran M, et al. Emergency hernia repairs in elderly patients. Am J Surg 2001;182: Sarr MG, Bulkley GB, Zuidema G. Preoperative recognition of intestinal strangulation obstruction: prospective evaluation of diagnostic capability. Am J Surg 1983;145: