ABSTRACT
BACKGROUND:
Emergency anterior abdominal wall hernia surgery plays a pivotal role in emergency general surgery practice. In this study, the predictive value of laboratory and imaging findings as well as demographic information and comorbidities of the patients for the recognition of strangulation and intestinal resection was investigated.
METHODS:
Patients over the age of 18 who were operated consecutively with an indication for emergency anterior abdominal wall hernia surgery between January 2017 and December 2019 in a single tertiary hospital were included in this retrospective cohort study. The patient population was divided into two groups according to the pre-operative findings during the emergency anterior abdominal wall hernia surgery. Group 1 consisted of cases with incarceration but without strangulation, whereas Group 2 consisted of cases with strangulation in addition to incarceration. Moreover, in evaluation for the requirement for intestinal resection, patient Group 2 was divided further into two groups, namely, as Group (1 or 2) a and Group (1 or 2) b, defining the need for intestinal resection.
RESULTS:
A total of 106 patients who had emergency anterior abdominal wall repair surgery due to incarcerated hernias were included in the study. The evaluation of the indices related to systemic inflammation revealed that lactate dehydrogenase to white blood cell ratio was significantly lower but neutrophil to platelet and neutrophil to albumin ratios were significantly higher in patients with strangulation, showing the significance of those systemic inflammation indices in detecting strangulation (p=0.027, p=0.035 and p=0.030, respectively). Moreover, the analysis of the patients in whom intestinal resection was required (Group 2a vs. 2b) exposed that neutrophil to albumin ratio was significantly higher in the patients with intestinal resection (p=0.036).
CONCLUSION:
Indices of systemic inflammation such as lactate dehydrogenase to white blood cell ratio, neutrophil to platelet ratio, and particularly neutrophil to albumin ratio may be potentially beneficial to prevent complications and improve clinical outcomes in emergency hernia surgery.
Keywords: Emergency anterior abdominal wall hernia surgery, intestinal resection, neutrophil to albumin ratio, strangulation
INTRODUCTION
Emergency anterior abdominal wall hernia surgery plays a pivotal role in emergency general surgery practice.[1] A delay in surgical management might result in obstruction and/or strangulation, especially in the presence of an incarceration. The presence of strangulation in incarcerated emergency cases might lead to necrosis, perforation, or intestinal resection. Incarceration and strangulation might increase the risk for pre-operative difficulties and post-operative complications. Complications associated with anesthesia as well as surgical complications such as hemorrhage, intra-abdominal abscess, or recurrence were suggested to increase in incarcerated or strangulated cases. Early recognition of those cases and appropriate preparation of both the patient and the surgical team as well as close follow-up of the patients might be helpful in reducing and improved managing of the complications associated with incarceration and strangulation.[2,3] In emergency cases, laboratory findings such as white blood cell counts (leukocytes and WBC), C-reactive protein levels (CRP), lactate dehydrogenase (LDH) levels, and imaging findings such as ultrasonography (US) and computed tomography (CT) scans can be used to detect strangulation.[3,4] In addition, clinical findings such as age, gender, comorbidities, and hernia type should be evaluated.[5]
Herein, the predictive value of laboratory and imaging findings as well as demographic information and comorbidities of the patients for the recognition of strangulation was investigated. Moreover, the influence of those clinical, laboratory, and patient-related parameters on post-operative complications and surgical complications according to the Clavien-Dindo Classification System was assessed. Finally, pre-operative findings of the patients with emergency anterior abdominal wall hernia surgery were studied with respect to obtaining appropriate prognostic implications and potentially contributing to their use during and after the surgery.
MATERIALS AND METHODS
Patients over the age of 18 who were operated consecutively with an indication for emergency anterior abdominal wall hernia (incisional, umbilical, inguinal, femoral, etc.) surgery between January 2017 and December 2019 in a single tertiary hospital were included in this retrospective and cohort study after receiving ethical approval from the local committee. Elective cases, patients who were operated for other emergent reasons, patients with additional anterior abdominal wall hernia repairs, patients with missing hospital records, and post-operative follow-up as well as patients under the age of 18 were excluded from the study. As shown in Figure 1, 106 out of 825 patients were selected to be included in the study following the application of the inclusion and exclusion criteria.
Figure 1.
Study flow diagram.
Demographic and clinical data of the patients such as age, gender, smoking habits, comorbidities according to Charlson comorbidity index, hernia type, operation type, presence of strangulation, mesh use, drain use, length of hospital stay, presence of local complications such as seroma, hematoma, and surgical site infection/abscess, stage of the complications according to Clavien-Dindo classification system, recurrence, reoperation, and the requirement for intestinal resection were analyzed. Pre-operative laboratory such as WBC counts (×103/μl), CRP (mg/dL) levels, LDH (IU/L), total (TBil, mg/dL) and indirect bilirubin (IBil, mg/dL) levels, neutrophil counts (×103/μl), lymphocyte (×103/μl), and platelet counts (×106/μl) as well as albumin (g/dL) levels values were evaluated, followed-by the calculation of various indicators of systemic inflammation to evaluate their prognostic significance, such as LDH to albumin ratio, LDH to WBC ratio (LDH/WBC), indirect bilirubin to albumin ratio (IBil/Albumin), lymphocyte to CRP ratio (LCR), neutrophil to platelet ratio (NPR), neutrophil to lymphocyte ratio (NLR), CRP to albumin ratio (CAR), platelet to albumin ratio (PAR), platelet to lymphocyte ratio (PLR), and neutrophil to albumin ratio (NAR). Furthermore, the location of the hernia, the maximum defect size, and the presence of obstruction as well as strangulation on imaging were evaluated by examining the pre-operative abdominal and superficial ultrasonographies.
The patient population was divided into two groups according to the pre-operative findings during the emergency anterior abdominal wall hernia surgery. Group 1 consisted of cases with incarceration but without strangulation, whereas Group 2 consisted of cases with strangulation in addition to incarceration. Moreover, in evaluation for the requirement for intestinal resection, patient Group 2 was divided further into two groups, namely, as Group 2a and Group 2b, defining the need for intestinal resection.
This study was conducted in accordance with the fundamental ethical principles for medical research involving human subjects, as stated in the guidelines of World Medical Association Declaration of Helsinki and was approved by the Local Ethics Committee (March 11, 2021-2021/120).
Statistical Methods
This study was designed as a retrospective study. Continuous variables were defined by descriptive statistics (mean, median, minimum-maximum, and standard variation). Normal distribution of continuous variables was evaluated using the Kolmogorov–Simirnov and Shapiro–Wilks tests. Two groups of continuous variables that were normally distributed were compared with Student’s t-test, whereas two groups that were not normally distributed were compared with Mann–Whitney U test. More than two groups of continuous variables that were not normally distributed were compared using the Kruskal–Wallis test. Dichotomous and categorical variables in two groups were compared with the Pearson Chi-square test. Fisher’s exact test was used where appropriate. The evaluation of the correlation between nonparametric variables was performed using the Spearman’s rank test and the strength of the correlation was determined and demonstrated according to the calculated Spearman’s Rho values. The level of statistical significance was determined as 0.05. All analyses were performed using IBM SPSS Statistics® Statistical Software Program version 25 (IBM Corporation, 1 New Orchard Road, Armonk, New York, United States).
RESULTS
A total of 106 patients who had emergency anterior abdominal wall repair surgery due to incarcerated hernias were included in the study. The study population consisted of 45 (42.4%) males and 61 (57.6%) females with an overall median age of 63 (minimum-maximum: 20–94 years). Among all, inguinal hernias were the most common anterior abdominal wall defects observed (n=41, 38.6%). Group 1 study group, which consisted of cases with incarceration but without strangulation included 57 (53.7%) patients, whereas Group 2 study group that consisted of cases with strangulation in addition to incarceration included 49 (46.3%) patients.
The demographic and clinical characteristics of the patients are listed in Table 1. No significant differences could be found between the Group 1 and Group 2 patients in terms of age, gender, smoking habits, and the presence of comorbidities (p=0.237, p=0.938, p=0.324 and p=0.560, respectively, Table 2). Cardiac disease was the most common comorbidity in the study population, with 37 patients (34.9%) (n=21, 19.8% in Group 1 vs. n=16, 15.1% in Group 2). In contrast, 38 (35.8%) patients were found not to have any comorbidities. (n=19, 17.9% in group 1 vs. n=19, 17.9% in Group 2, Tables 1 and 2). Median Charlson comorbidity index point of the patients in Group 1 was 3 (0–6, Minimum-maximum), whereas the median Charlson comorbidity index point of the patients in Group 2 was 2 (0–6, Minimum-maximum). No statistically significant difference could be observed in terms of median Charlson comorbidity index points between the two patient groups (p=0.166, Table 2).
Table 1.
Patient characteristics
| Group 1 n (%) | Group 2 n (%) | Total | |||
|---|---|---|---|---|---|
|
|
|
||||
| Male | Female | Male | Female | ||
| Number of patients | 24 (22.6) | 33 (31.1) | 21 (19.8) | 28 (26.4) | 106 (100) |
| Smoking habitus | 8 (7.5) | 3 (2.8) | 5 (4.7) | 1 (0.9) | 17 (15.9) |
| Median age (years) (Min-Max) | 61 (20–89) | 69 (35–93) | 62 (23–94) | 57 (31–82) | |
| History of any comorbidities | 13 (12.3) | 25 (23.6) | 12 (11.3) | 18 (17.0) | 68 (64.3) |
| Type of comorbidity | |||||
| Cardiac | 8 (7.5) | 13 (12.3) | 7 (6.6) | 9 (8.5) | 37 (34.9) |
| Endocrine | 2 (1.9) | 4 (3.8) | 2 (1.9) | 7 (6.6) | 15 (14.2) |
| Respiratory | 3 (2.8) | 1 (0.9) | 1 (0.9) | 1 (0.9) | 6 (5.7) |
| Renal | 0 | 1 (0.9) | 2 (1.9) | 0 | 3 (2.8) |
| Rheumatological | 0 | 4 (3.8) | 0 | 1 (0.9) | 5 (4.7) |
| Malignancy | 0 | 2 (1.9) | 0 | 0 | 2 (1.9) |
| Charlson Comorbidity Index | |||||
| 0 | 9 (8.5) | 3 (2.8) | 4 (3.8) | 5 (4.7) | 21 (19.8) |
| 1 | 1 (0.9) | 2 (1.9) | 4 (3.8) | 3 (2.8) | 10 (9.4) |
| 2 | 2 (1.9) | 5 (4.7) | 3 (2.8) | 7 (6.6) | 17 (16.0) |
| 3 | 1 (0.9) | 8 (7.5) | 3 (2.8) | 5 (4.7) | 17 (16.0) |
| 4 | 5 (4.7) | 8 (7.5) | 4 (3.8) | 6 (5.7) | 23 (21.7) |
| 5 | 5 (4.7) | 6 (5.7) | 1 (0.9) | 2 (1.9) | 14 (13.2) |
| 6 | 1 (0.9) | 1 (0.9) | 2 (1.9) | 0 | 4 (3.8) |
| Mesh use | 18 (17.0) | 13 (12.3) | 10 (9.4) | 10 (9.4) | 51 (48.1) |
| Drain use | 7 (6.6) | 12 (11.3) | 12 (11.3) | 19 (17.9) | 50 (47.2) |
| Operation type | |||||
| Open | 22 (20.8) | 32 (30.2) | 21 (19.8) | 27 (25.5) | 102 (96.2) |
| Laparoscopic | 2 (1.9) | 1 (0.9) | 0 | 1 (0.9) | 4 (3.8) |
| Hernia type | |||||
| Indirect inguinal | 14 (13.2) | 5 (4.7) | 10 (9.4) | 2 (1.9) | 31 (29.2) |
| Direct inguinal | 2 (1.9) | 3 (2.8) | 4 (3.8) | 1 (0.9) | 10 (9.4) |
| Pantaloon | 1 (0.9) | 0 | 0 | 0 | 1 (0.9) |
| Femoral | 1 (0.9) | 7 (6.6) | 1 (0.9) | 3 (2.8) | 12 (11.3) |
| Umbilical | 3 (2.8) | 11 (10.4) | 5 (4.7) | 13 (12.3) | 32 (30.2) |
| Epigastric | 2 (1.9) | 0 | 0 | 0 | 2 (1.9) |
| Spigelian | 0 | 0 | 0 | 1 (0.9) | 1 (0.9) |
| Obturator | 0 | 0 | 0 | 1 (0.9) | 1 (0.9) |
| Incisional | 1 (0.9) | 7 (6.6) | 1 (0.9) | 7 (6.6) | 16 (15.1) |
| Hernia localization | |||||
| Inguinal | 18 (17.0) | 15 (14.2) | 14 (13.2) | 6 (5.7) | 53 (50.0) |
| Non-inguinal | 6 (5.7) | 18 (17.0) | 7 (6.6) | 22 (20.8) | 53 (50.0) |
| Recurrence | 1 (0.9) | 3 (2.8) | 1 (0.9) | 5 (4.7) | 10 (9.4) |
| Reoperation | 1 (0.9) | 3 (2.8) | 1 (0.9) | 7 (6.6) | 12 (11.3) |
| Side effects according to the Clavien-Dindo | |||||
| Classification System | |||||
| I | 15 (14.2) | 15 (14.2) | 9 (8.5) | 5 (4.7) | 44 (41.5) |
| II | 7 (6.6) | 10 (9.4) | 3 (2.8) | 6 (5.7) | 26 (24.5) |
| IIIa and IIIb | 0 | 0 | 0 | 1 (0.9) | 1 (0.9) |
| IVa and IVb | 2 (1.9) | 7 (6.6) | 9 (8.5) | 14 (13.2) | 32 (30.2) |
| V | 0 | 1 (0.9) | 0 | 0 | 1 (0.9) |
| Presence of any local complications | |||||
| Seroma | 1 (0.9) | 2 (1.9) | 0 | 0 | 3 (2.8) |
| Hematoma | 0 | 0 | 0 | 1 (0.9) | 1 (0.9) |
| Mesh reaction | 0 | 0 | 0 | 0 | 0 |
| Surgical site infection/abscess | 2 (1.9) | 3 (2.8) | 2 (1.9) | 6 (5.7) | 13 (12.3) |
| Wound dehiscence | 0 | 0 | 0 | 0 | 0 |
| Pre-operative US finding of strangulation | |||||
| No strangulation | 20 (18.9) | 20 (18.9) | 4 (3.8) | 15 (14.2) | 59 (55.7) |
| Strangulation | 4 (3.8) | 13 (12.3) | 17 (16.0) | 13 (12.3) | 47 (44.3) |
| Intestinal resection requirement | 0 | 1 (0.9) | 11 (10.4) | 14 (13.2) | 26 (24.5) |
Min: Minimum; Max: Maximum; US: Ultrasonography.
Table 2.
Comparison of the pre-operative data between Group 1 and 2
| Group 1 (Median [Min-Max]) | Group 1 (Median [Min-Max]) | p-value | |
|---|---|---|---|
| Median age (years) (Min-Max) | 66 (20–93) | 60 (23–94) | 0.237 |
| Gender | |||
| Male | 24 | 21 | 0.938 |
| Female | 33 | 28 | |
| Smoking habitus | 0.324 | ||
| Present | 11 | 6 | |
| Absent | 46 | 43 | |
| Type of comorbidities | 0.481 | ||
| Cardiac | 21 | 16 | |
| Endocrine | 6 | 9 | |
| Respiratory | 4 | 2 | |
| Renal | 1 | 2 | |
| Rheumatological | 4 | 1 | |
| Malignancy | 2 | 0 | |
| History of comorbid diseases | 0.560 | ||
| Present | 38 | 30 | |
| Absent | 19 | 19 | |
| Charlson Comorbidity Index | 3 (0–6) | 2 (0–6) | 0.166 |
| Preoperative WBC count (×103/μl) | 9000 (4500–20100) | 11500 (4500–25660) | 0.004 |
| Pre-operative CRP levels (mg/dL) | 16.64 (0.26–248.32) | 15.97 (0.30–338.15) | 0.255 |
| Pre-operative LDH levels (IU/L) | 222.5 (145.0–1241.0) | 218.0 (116.0–518.0) | 0.314 |
| Pre-operative neutrophil count (×103/μl) | 6500 (2900–17600) | 8400 (3300–23710) | 0.005 |
| Pre-operative IBil levels (mg/dL) | 0.56 (0.02–1.96) | 0.53 (0.11–1.82) | 0.779 |
| Pre-operative lymphocyte count (×103/μl) | 1700 (300–3400) | 1700 (300–5000) | 0.819 |
| Pre-operative platelet count (×106/μl) | 248 (127–487) | 259 (100–489) | 0.190 |
| Pre-operative albumin levels (g/dL) | 3.43 (1.99–4.84) | 3.40 (2.06–4.94) | 0.679 |
| Pre-operative LAR | 68.88 (36.93–256.41) | 66.87 (34.96–189.45) | 0.423 |
| Pre-operative LDH/WBC | 0.023 (0.000–0.124) | 0.019 (0.006–0.053) | 0.027 |
| Pre-operative IBil/Albumin | 0.154 (0.005–0.599) | 0.172 ()0.000–0.671) | 0.684 |
| Pre-operative LCR | 88.63 (3.92–6538.46) | 76.75 (2.66–4000.00) | 0.451 |
| Pre-operative NPR | 0.027 (0.011–0.066) | 0.033 (0.010–0.112) | 0.035 |
| Pre-operative NLR | 3.64 (0.97–43.33) | 4.82 (1.00–53.33) | 0.096 |
| Pre-operative CAR | 4.58 (0.08–106.58) | 5.72 (0.08–114.30) | 0.308 |
| Pre-operative PAR | 71572.83 (28995.43–232663.32) | 73756.51 (26595.75–204854.37) | 0.273 |
| Pre-operative PLR | 150.00 (40.97–860.00) | 147.92 (49.20–1055.00) | 0.768 |
| Pre-operative NAR | 1828.50 (871.80–5577.89) | 2466.54 (962.10–6504.07) | 0.030 |
| The maximum defect size according to | 23 (6–60) | 24 (9–100) | 0.720 |
| pre-operative US (mm) | |||
| Pre-operative US finding of strangulation | 0.001 | ||
| No strangulation | 40 | 19 | |
| Strangulation | 17 | 30 |
Min: Minimum; Max: Maximum; US: Ultrasonography; mm: Millimeter; WBC: White blood cells; CRP: C-Reactive protein; LDH: Lactate dehydrogenase; IBil: Indirect bilirubin; LAR: LDH to Alb ratio; LDH/WBC: LDH to WBC ratio; IBil/Albumin: Indirect bilirubin to albumin ratio; LCR: Lymphocyte to CRP ratio; NPR: Neutrophil to platelet ratio; NLR: Neutrophil to lymphocyte ratio; CAR: CRP to albumin ratio; PAR: Platelet to albumin ratio; PLR: Platelet to lymphocyte ratio; NAR: Neutrophil to albumin ratio. Statistically significant results (p<0.05) were written in bold format.
It was detected that the type of the surgical procedure (open or laparoscopic) and mesh usage did not differ significantly in both groups (p=0.622 and p=0.163, respectively), whereas the use of closed-suction drains was found to be more common in Group 2 (p=0.002). The distribution of inguinal and other hernias was also similar between the two groups (p=0.080, Table 3). Furthermore, there were not any significant differences between the two groups in terms of the presence of recurrence, reoperation, or local complications (p=0.359, p=0.132 and p=0.545, respectively), though it was determined that complications equal to or greater than Grade 2 according to Clavien-Dindo classification system were more common in group 2 (p=0.001). In addition, it was found out that Group 2 patients stayed significantly longer in the hospital (p=0.009, Table 3). Mortality was observed in only one patient in Group 1 over the whole course of the study.
Table 3.
Comparison of the intraoperative and post-operative data between Group 1 and 2
| Group 1 (Median [Min-Max]) | Group 1 (Median [Min-Max]) | p-value | |
|---|---|---|---|
| Mesh use | 31 | 20 | 0.163 |
| Present | 26 | 29 | |
| Absent | 0.002 | ||
| Drain use | 19 | 31 | |
| Used | 38 | 18 | |
| None | |||
| Requirement for intestinal resection | <0.001 | ||
| Present | 1 | 25 | |
| Absent | 56 | 24 | |
| Operation type | 0.622 | ||
| Open | 54 | 48 | |
| Laparoscopic | 3 | 1 | |
| Localization of the hernia defect | 0.080 | ||
| Inguinal | 33 | 20 | |
| Non-inguinal | 24 | 29 | |
| Duration of hospitalization (days) | 3 (1–18) | 5 (1–31) | 0.009 |
| Recurrence | 4/57 | 6/49 | 0.359 |
| Re-operation | 4/57 | 8/49 | 0.132 |
| Side effects according to Clavien-Dindo | |||
| Classification System | |||
| No complication | 0 | 2 | |
| Class I | 30 | 14 | |
| Class II | 17 | 9 | |
| Class IIIa and IIIb | 0 | 1 | |
| Class IVa and IVb | 9 | 23 | |
| Class V | 1 | 0 | |
| Side effects according to Clavien-Dindo | 0.001 | ||
| Classification System | |||
| Class 0-I-II | 47 | 25 | |
| Class >II | 10 | 24 | |
| Presence of local complications | |||
| No local complications | 49 | 40 | |
| Seroma | 3 | 0 | |
| Hematoma | 0 | 1 | |
| Surgical site infection/abscess | 5 | 8 | |
| Presence of local complications | 0.545 | ||
| Absence | 49 | 40 | |
| Presence | 8 | 9 |
Min: Minimum; Max: Maximum. Statistically significant results (p<0.05) were written in bold format.
The presence of pre-operative ultrasonographic findings concerning strangulation significantly determined the risk for finding signs of strangulation intraoperatively (Odds Ratio [OR] = 3.715, 95% confidence interval [CI]: 1.657–8.331, p=0.001). However, the presence of pre-operative sonographic findings of strangulation could not be able to dictate the risk for intestinal resection (OR=2.045, 95% CI: 0.834–5.018, p=0.115). Furthermore, patients with strangulation findings did not demonstrate significantly different defect sizes according to pre-operative imaging than those in patients without any strangulation findings (p=0.720, Table 2).
It was identified that pre-operative CRP levels, LDH levels, total and indirect bilirubin levels, lymphocyte counts, platelet counts, and albumin levels did not differ significantly between the patients without strangulation and those with strangulation (p=0.255, p=0.314, 0.756, p=0.779, p=0.819, p=0.190, and p=0.736, respectively). In contrast, pre-operative WBC and neutrophil counts were significantly higher in patients with strangulation (Group 2) (p=0.004 and p=0.005, respectively, Table 2).
The evaluation of the indices related to systemic inflammation revealed that LDH/WBC ratio was significantly lower but NPR and NAR ratios were significantly higher in patients with strangulation, showing the significance of those systemic inflammation indices in detecting strangulation (p=0.027, p=0.035 and p=0.030, respectively, Table 2). Moreover, the analysis of the patients in whom intestinal resection was required (Group 2a vs. 2b) exposed that NAR was significantly higher in the patients with intestinal resection (p=0.036, Table 4 and Fig. 2). The reason for intestinal resection in a patient without any strangulation was iatrogenic injury due to massive intra-abdominal adhesions.
Table 4.
Comparison of the Group 2a (no need for intestinal resection) and Group 2b (intestinal resection performed) patients within the patients of Group 2 (strangulation) in terms of different ratios of pre-operative laboratory tests
| Group 2a | Group 2b | p-value | |
|---|---|---|---|
| Pre-operative WBC count (x103/μl) | 10950 (5200–25660) | 12800 (4500–24480) | 0.114 |
| Pre-operative CRP levels (mg/dL) | 12.20 (0.30–190.21) | 69.30 (1.14–338.15) | 0.201 |
| Pre-operative LDH levels (IU/L) | 211 (116–518) | 219 (121–485) | 0.828 |
| Pre-operative neutrophil count (x103/μl) | 7650 (3500–23710) | 9700 (3300–21660) | 0.089 |
| Pre-operative IBil levels (mg/dL) | 0.52 (0.22–1.13) | 0.53 (0.11–1.82) | 0.332 |
| Pre-operative lymphocyte count (x103/μl) | 1800 (500–4400) | 1500 (300–5000) | 0.347 |
| Pre-operative platelet count (x106/μl) | 257 (100–476) | 273 (142–489) | 0.562 |
| Pre-operative albumin levels (g/dL) | 3.51 (2.70–4.94) | 3.31 (2.06–4.60) | 0.283 |
| Pre-operative LAR | 62.39 (34.96–130.16) | 67.37 (35.59–189.45) | 0.570 |
| Pre-operative LDH/WBC | 0.02 (0.01–0.05) | 0.02 (0.01–0.05) | 0.444 |
| Pre-operative IBil/Albumin | 0.17 (0.00–0.41) | 0.18 (0.03–0.67) | 0.132 |
| Pre-operative LCR | 139.18 (7.41–4000.00) | 28.04 (2.66–1975.61) | 0.078 |
| Pre-operative NPR | 0.03 (0.02–0.11) | 0.04 (0.01–0.10 | 0.230 |
| Pre-operative NLR | 3.92 (1.91–20.88) | 7.53 (1.00–53.33) | 0.093 |
| Pre-operative CAR | 3.27 (0.08–51.41) | 19.83 (0.33–114.30) | 0.176 |
| Preoperative PAR | 72036.47 (26595.75–128648.65) | 79301.75 (40000.00–204854.37) | 0.403 |
| Pre-operative PLR | 137.16 (76.59–504.00) | 196.15 (49.20–1055.00) | 0.097 |
| Pre-operative NAR | 2255.44 (1282.05–6408.11) | 2893.98 (962.10–6504.07) | 0.036 |
Min: Minimum; Max: Maximum; US: Ultrasonography; mm: Millimeter; WBC: White blood cells; CRP: C-Reactive protein; LDH: Lactate dehydrogenase; IBil: Indirect bilirubin; LAR: LDH to albumin ratio; LDH/WBC: LDH to WBC ratio; IBil/Albumin: Indirect bilirubin to albumin ratio; LCR: Lymphocyte to CRP ratio; NPR: Neutrophil to platelet ratio; NLR: Neutrophil to lymphocyte ratio; CAR: CRP to albumin ratio, PAR: Platelet to albumin ratio; PLR: Platelet to lymphocyte ratio; NAR: Neutrophil to albumin ratio. Statistically significant results (p<0.05) were written in bold format.
Figure 2.
The distribution of NAR (Neutrophil to Albumin ratio) in patients with and without intestinal resection within patients in Group 2. The median levels are indicated as bold thick lines within each box-plot graph. The difference is statistically significant (p=0.036).
DISCUSSION
The repair of anterior abdominal wall hernias is a vital part of both emergency and elective surgery. In addition, emergency inguinal hernia repairs are performed nearly as often as appendectomies.[6] It was previously stated that similar to the situation in elective practice, the most common localization in emergency anterior abdominal wall hernias was the groin region.[7,8] Accordingly, comparable results were obtained in this study. Incarceration was suggested as the main indication in emergency hernia surgery, which could result in obstruction and strangulation. Therefore, patients might present with acute mechanical intestinal obstruction, necrosis, perforation, or intra-abdominal abscess, which might impose the resection or excision of intra-abdominal structures.[9] In this study, patients who underwent emergency anterior abdominal wall hernia repair surgery were operated with an indication of incarceration and they were grouped according to whether or not strangulation accompanied their pre-operative findings.
Sneiders et al.[10] investigated the risk factors for incarceration in 4472 patients operated for primary anterior abdominal wall and incisional hernias and indicated that age for primary hernias as well as age, female gender, and diabetes mellitus (endocrine disease) for incisional hernias were found to be associated with incarceration. Likewise, Simsek et al.[11] questioned the factors affecting strangulation, necrosis, and mortality in incarcerated anterior abdominal wall hernia repair surgeries and argued that factors such as age, gender, comorbidity, hernia type, and lateralization did not influence strangulation, necrosis, or mortality. Correspondingly, the results of this study revealed that age, gender, or comorbidities were found not to associate with strangulation. The duration of pre-operative symptoms longer than 24 h was previously suggested to be a significant predictor of strangulation and necrosis.[6] However, the duration of symptoms before surgery was neither registered nor analyzed in this manuscript, which could be regarded among the limitations of this study.
Yang[12] proposed in a review article that laparoscopy was getting increasingly more common in emergency hernia repair, in accordance with the statement in this manuscript that the rate of laparoscopic surgery had increased especially in emergency inguinal hernia surgery. Furthermore, it was suggested that laparoscopy in emergency anterior abdominal wall surgery should only be performed in centers with immense experience and without surgical equipment limitations. In this manuscript, however, it was denoted that there was no significant difference in laparoscopic technique between the two groups, though laparoscopic surgery was performed only in 4 (3.8%) patients in a series of 106 patients. That low number of laparoscopic surgeries reported in this manuscript might hinder any comparison between the open and laparoscopic techniques in emergency anterior abdominal wall hernia repair, which might be counted as another limitation of this study.
Abd Ellatif et al.[13] previously claimed that mesh usage was safe in strangulated hernia repairs even in the event of an inevitable intestinal resection. However, the results of the present study did not reveal any statistically significant difference between the incarcerated cases without any intestinal resection and those with intestinal resection. Ergül et al.[14] suggested in their study that closed-suction drains were used more often in emergency surgeries and that the use of those drains did not increase the risk of infections, though closed-suction drain use was associated with a longer hospital stay. However, Xourafas et al.[15] stated that drain usage was not associated with increased morbidity or mortality. The results of the present study as well revealed that closed-suction drains were used more common in strangulated hernias.
It was repeatedly reported in a vast number of the previous studies that complications were more common in emergency hernia surgery. Similarly, it is widely accepted that local and systemic complications are more common in incarcerated cases accompanied by strangulation, which may result in longer hospital stays, recurrences, and reoperations.[3,16] However, the rate of recurrences, reoperations, and local complications were found not to differ significantly between different patient groups in the present study, although post-operative surgical complications of Grade 2 or more according to Clavien-Dindo classification system were more common in patients with strangulation (Group 2).
Imaging findings such as the presence of free fluid, intestinal wall thickening, peristalsis, air echogenicity-density, and the size of the defect were suggested to aid in detecting strangulation. In addition, it was proposed in a number of the previous studies that US was more appropriate than CT for detecting strangulation in incarcerated cases.[17,18] It was also suggested that although the size of the defect might play a role in the presence of an incarceration, it was not an independent risk factor for strangulation.[18,19] The main imaging modality used in the present study was US, as well. Moreover, the results of the present study revealed that the rate of determining intraoperative sonographic findings of strangulation was higher in patients with pre-operative findings of strangulation, whereas pre-operative normal sonographic findings were associated with no intraoperative finding of strangulation (p=0.001) and the odds for a patient demonstrating pre-operative strangulation findings in US of being diagnosed intraoperatively for strangulation is 3.715 (95% CI 1.657–8.331, p=0.001).
It was previously demonstrated in various studies that WBC and neutrophil counts were associated with ischemic bowel and increased bowel resection.[20,21] Moreover, pre-operative platelet, lymphocyte, and neutrophil counts as well as albumin levels were shown to significantly differ in predicting surgical site infections in a study group with patients suffering from groin hernias repaired with meshes.[22] Although neutrophil and WBC counts were demonstrated to significantly associate with strangulation in the present study, no other pre-operative blood tests differed significantly between the two patient groups (group 1 vs. group 2).
Zhou et al.[23] reported that NLR was the most suitable index for detecting strangulation in a retrospective series of 263 patients. Similarly, Yildirim et al.[24] indicated that LCR and NLR were significant in the prediction of both intestinal ischemia and resection in strangulated anterior abdominal wall hernias. While Zhuo et al.[22] suggested NLR and PLR as predictive indices in emergency groin hernia surgery, their findings failed to demonstrate any significantly predictive value for the lymphocyte to monocyte ratio (LMR). Ikeguchi et al.[25] indicated that both CAR and NLR were significantly associated with operative morbidity and mortality in emergency ileus cases with bowel strangulation. Although any analysis of LAR has not yet been reported in the current emergency hernia surgery literature, its value was previously demonstrated as a parameter that affected mortality in severe infections requiring intensive care.[26] Other indices were also shown to associate with either disease diagnosis, clinical outcomes, morbidity, or mortality in various previous studies, such as the NPR in cardiac emergencies, IBil/Albumin in neurological and neonatal emergencies, LDH/WBC in systemic inflammation and the prognosis of Coronavirus disease-19, PAR in cancers of especially the hepatobiliary system, and NAR in sepsis and septic shock.[27–32] The results of the present study revealed that among the indices commonly used as indicators of systemic inflammation in various diseases LDH/WBC, NPR and NAR were significantly associated with strangulation in emergency anterior abdominal wall hernias.
In addition to not specifying the duration of pre-operative symptoms, single imaging technique (US) used for the evaluation and the inability to access some patient data, the retrospective, single-center, and non-randomized design with limited number of patients in a limited study time frame may comprise other limitations of the present study. Growing but yet scarce number of studies in the present literature evaluating indices as systemic inflammatory indicators or the fact that their analyses were in fields other than surgical emergencies could also be counted among other limitations. Nevertheless, it should not be neglected that studies evaluating the potential use of indices of systemic inflammation are currently at their infancy and only a minute portion of current literature includes such studies.
Conclusion
Strangulation and ultimately intestinal resection are two serious conditions that may influence operative morbidity and mortality. In addition to US as a valuable diagnostic tool and WBC counts as well as neutrophil counts as significant pre-operative blood tests, indices of systemic inflammation such as LDH/WBC, NPR and particularly NAR may be potentially beneficial to prevent complications and improve clinical outcomes in emergency hernia surgery.
Footnotes
Ethics Committee Approval: This study was approved by the University of Health Sciences, Gülhane Scientific Research Ethics Committee (Date: 11.03.2021, Decision No: 2021/120).
Peer-review: Externally peer-reviewed.
Authorship Contributions: Concept: M.Z.B., S.A.K.; Design: M.Z.B., S.A.K.; Supervision: M.Z.B., S.A.K.; Resource: M.Z.B.; Materials: S.A.K.; Data: Ş.Ç., B.U.; Analysis: S.A.K.; Literature search: M.Z.B.; Writing: M.Z.B.; Critical revision: S.A.K.
Conflict of Interest: None declared.
Financial Disclosure: The authors declared that this study has received no financial support.
REFERENCES
- 1.Primatesta P, Goldacre MJ. Inguinal hernia repair:Incidence of elective and emergency surgery, readmission and mortality. Int J Epidemiol. 1996;25:835–9. doi: 10.1093/ije/25.4.835. [DOI] [PubMed] [Google Scholar]
- 2.Orchard MR, Wright JA, Kelly A, McCabe DJ, Hewes J. The impact of healthcare rationing on elective and emergency hernia repair. Hernia. 2016;20:405–9. doi: 10.1007/s10029-015-1441-y. [DOI] [PubMed] [Google Scholar]
- 3.Birindelli A, Sartelli M, Di Saverio S, Coccolini F, Ansaloni L, van Ramshorst GH, et al. 2017 update of the WSES guidelines for emergency repair of complicated abdominal wall hernias. World J Emerg Surg. 2017;12:37. [Google Scholar]
- 4.Chen P, Yang W, Zhang J, Wang C, Yu Y, Wang Y, et al. Analysis of risk factors associated bowel resection in patients with incarcerated groin hernia. Medicine (Baltimore) 2020;99:e20629. doi: 10.1097/MD.0000000000020629. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 5.Russell TB, Elberm H. Emergency hernia surgery at a high-volume tertiary centre:A 3-year experience. ANZ J Surg. 2021;91:622–6. doi: 10.1111/ans.16597. [DOI] [PubMed] [Google Scholar]
- 6.Yeh DD, Alam HB. Hernia emergencies. Surg Clin North Am. 2014;94:97–130. doi: 10.1016/j.suc.2013.10.009. [DOI] [PubMed] [Google Scholar]
- 7.Ozkan E, Yıldız MK, Cakır T, Dulundu E, ErişC , Fersahoğlu MM, et al. Incarcerated abdominal wall hernia surgery:Relationship between risk factors and morbidity and mortality rates (a single center emergency surgery experience) Ulus Travma Acil Cerrahi Derg. 2012;18:389–96. doi: 10.5505/tjtes.2012.48827. [DOI] [PubMed] [Google Scholar]
- 8.Vironen J. Treatment of incarcerated hernia in adults. Duodecim. 2017;133:849–54. [PubMed] [Google Scholar]
- 9.Surek A, Gemici E, Ferahman S, Karli M, Bozkurt MA, Dural AC, et al. Emergency surgery of the abdominal wall hernias:Risk factors that increase morbidity and mortality-a single-center experience. Hernia. 2021;25:679–88. doi: 10.1007/s10029-020-02293-5. [DOI] [PubMed] [Google Scholar]
- 10.Sneiders D, Yurtkap Y, Kroese LF, Kleinrensink GJ, Lange JF, Gillion JF, et al. Risk factors for incarceration in patients with primary abdominal wall and incisional hernias:A prospective study in 4472 patients. World J Surg. 2019;43:1906–13. doi: 10.1007/s00268-019-04989-x. [DOI] [PubMed] [Google Scholar]
- 11.Şimşek A, Kocaaslan H, Dirican A, Ateş M. Factors affecting strangulation and necrosis in incarcerated abdominal wall hernias. Cyprus J Med Sci. 2020;5:279–83. [Google Scholar]
- 12.Yang G. Laparoscopy in emergency hernia repair. Ann Laparosc Endosc Surg. 2017;2:6. [Google Scholar]
- 13.Abd Ellatif ME, Negm A, Elmorsy G, Al-Katary M, Yousef AE, Ellaithy R. Feasibility of mesh repair for strangulated abdominal wall hernias. Int J Surg. 2012;10:153–6. doi: 10.1016/j.ijsu.2012.02.004. [DOI] [PubMed] [Google Scholar]
- 14.Ergül Z, Akinci M, Yilmaz KB, Sahin A, Seker G, Kulaçoğlu H. Why do we use drains in some inguinal hernia repairs? Chirurgia (Bucur) 2011;106:769–74. [PubMed] [Google Scholar]
- 15.Xourafas D, Lipsitz SR, Negro P, Ashley SW, Tavakkolizadeh A. Impact of mesh use on morbidity following ventral hernia repair with a simultaneous bowel resection. Arch Surg. 2010;145:739–44. doi: 10.1001/archsurg.2010.144. [DOI] [PubMed] [Google Scholar]
- 16.Misiakos EP, Bagias G, Zavras N, Tzanetis P, Patapis P, Machairas A. Strangulated inguinal hernia. In: Canonico S, editor. Inguinal Hernia. London: IntechOpen; 2014. [Accessed Jan 2, 2022]. Available from: https://www.intechopen.com/chapters/46889 . [Google Scholar]
- 17.Lassandro F, Iasiello F, Pizza NL, Valente T, Stefano ML, Grassi R, et al. Abdominal hernias:Radiological features. World J Gastrointest Endosc. 2011;3:110–7. doi: 10.4253/wjge.v3.i6.110. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18.Jayaram PR, Pereira FD, Barrett JA. Evaluation of dynamic ultrasound scanning in the diagnosis of equivocal ventral hernias with surgical comparison. Br J Radiol. 2018;91:20180056. doi: 10.1259/bjr.20180056. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19.Derici H, Unalp HR, Bozdag AD, Nazli O, Tansug T, Kamer E. Factors affecting morbidity and mortality in incarcerated abdominal wall hernias. Hernia. 2007;11:341–6. doi: 10.1007/s10029-007-0226-3. [DOI] [PubMed] [Google Scholar]
- 20.Keeley JA, Kaji A, Kim DY, Putnam B, Neville A. Predictors of ischemic bowel in patients with incarcerated hernias. Hernia. 2019;23:277–80. doi: 10.1007/s10029-019-01884-1. [DOI] [PubMed] [Google Scholar]
- 21.Chen P, Huang L, Yang W, He D, Liu X, Wang Y, et al. Risk factors for bowel resection among patients with incarcerated groin hernias:A meta-analysis. Am J Emerg Med. 2020;38:376–83. doi: 10.1016/j.ajem.2019.09.023. [DOI] [PubMed] [Google Scholar]
- 22.Zhuo Y, Cai D, Chen J, Zhang Q, Li X. Pre-surgical peripheral blood inflammation markers predict surgical site infection following mesh repair of groin hernia. Medicine (Baltimore) 2021;100:e25007. doi: 10.1097/MD.0000000000025007. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 23.Zhou H, Ruan X, Shao X, Huang X, Fang G, Zheng X. Clinical value of the neutrophil/lymphocyte ratio in diagnosing adult strangulated inguinal hernia. Int J Surg. 2016;36:76–80. doi: 10.1016/j.ijsu.2016.10.026. [DOI] [PubMed] [Google Scholar]
- 24.Yildirim M, Dasiran F, Angin YS, Okan I. Lymphocyte-C-reactive protein ratio:A putative predictive factor for intestinal ischemia in strangulated abdominal wall hernias. Hernia. 2021;25:733–9. doi: 10.1007/s10029-020-02174-x. [DOI] [PubMed] [Google Scholar]
- 25.Ikeguchi M, Hanaki T, Kihara KI, Endo K, Suzuki K, Nakamura S, et al. Correlation of operative mortality and morbidity with preoperative C-reactive protein/albumin ratio, neutrophil/lymphocyte ratio, and prognostic nutritional index in patients undergoing emergent operations due to strangulation ileus. Int Surg. 2021;105:278–83. [Google Scholar]
- 26.Jeon SY, Ryu S, Oh SK, Park JS, You YH, Jeong WJ, et al. Lactate dehydrogenase to albumin ratio as a prognostic factor for patients with severe infection requiring intensive care. Medicine (Baltimore) 2021;100:e27538. doi: 10.1097/MD.0000000000027538. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 27.Wang Y, Sheng G, Shi L, Cheng X. Increased serum total bilirubin-albumin ratio was associated with bilirubin encephalopathy in neonates. Biosci Rep. 2020;40:BSR20192152. doi: 10.1042/BSR20192152. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 28.Somaschini A, Cornara S, Demarchi A, Mandurino-Mirizzi A, Fortuni F, Crimi G, et al. Neutrophil to platelet ratio:A novel prognostic biomarker in ST-elevation myocardial infarction patients undergoing primary percutaneous coronary intervention. Eur J Prev Cardiol. 2020;19:2338–40. doi: 10.1177/2047487319894103. [DOI] [PubMed] [Google Scholar]
- 29.Saito N, Shirai Y, Horiuchi T, Sugano H, Shiba H, Sakamoto T, et al. Preoperative platelet to albumin ratio predicts outcome of patients with cholangiocarcinoma. Anticancer Res. 2018;38:987–92. doi: 10.21873/anticanres.12313. [DOI] [PubMed] [Google Scholar]
- 30.Gong Y, Li D, Cheng B, Ying B, Wang B. Increased neutrophil percentage-to-albumin ratio is associated with all-cause mortality in patients with severe sepsis or septic shock. Epidemiol Infect. 2020;148:e87. doi: 10.1017/S0950268820000771. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 31.Varim C, Yaylaci S, Demirci T, Kaya T, Nalbant A, Dheir H, et al. Neutrophil count to albumin ratio as a new predictor of mortality in patients with COVID-19 ınfection. Rev Assoc Med Bras (1992) 2020;66(Suppl 2):77–81. doi: 10.1590/1806-9282.66.S2.77. [DOI] [PubMed] [Google Scholar]
- 32.Shen H, Dai Z, Wang M, Gu S, Xu W, Xu G, et al. Preprocedural neutrophil to albumin ratio predicts in-stent restenosis following carotid angioplasty and stenting. J Stroke Cerebrovasc Dis. 2019;28:2442–7. doi: 10.1016/j.jstrokecerebrovasdis.2019.06.027. [DOI] [PubMed] [Google Scholar]