Treatment of de Garengeot's hernia: a meta-analysis

Purpose

de Garengeot’s hernia is a rare entity in which the appendix is located within a femoral hernia and is almost invariably encountered incarcerated in an emergency setting with concomitant appendicitis. In the literature, there are mostly single-case reports. The purpose of the present study was to perform a review of the literature to study the incidence, pathogenesis, demographics, clinical presentation, laboratory and radiological investigations, differential diagnosis, delay in diagnosis and treatment, operative findings, surgical technique, histological findings, the postoperative course, use of antibiotics, and complications regarding de Garengeot’s hernia.

Methods

A literature search was performed through PubMed with the following search terms, single or in combination: Garengeot, femoral hernia, and appendicitis. Additional references were also found within the articles, and two patients from Uppsala University Hospital were added.

Results

Between 1981 and 2016, 70 publications were identified, and with the additional two patients, the present series comprised 90 patients There were 75 women (median age 73.0 years) and 15 men (median age 78.0 years). On examination, an inguinal mass was found in 87 patients (97%), which was painful and the cause of primary complaint in 67 patients (74%): the median duration of symptoms was 3 days. Radiological investigations or ultrasound were performed in 67 patients (74%); computed tomography was the most accurate with a positive diagnosis in 23/34 patients. Appendicitis was found in 76 patients, gangrenous in 23, and perforated in 9. The surgical approach was inguinal in 76 patients, including 15 with concomitant laparotomy. The preperitoneal route was chosen in six patients, and laparoscopy alone in four patients. A mesh/plug was used in 22 patients (7/22 normal appendix) and suture repair in 59 (4/59 normal appendix: p < 0.01). Complications were analysed in 79 patients and occurred in 11%. There was no mortality.

Conclusions

de Garengeot’s hernia is rare, being indistinguishable from an incarcerated femoral hernia in general. A delay in surgery should be avoided but if needed, computed tomography may be used for differential diagnosis. Although there is no standard treatment, mesh material does not appear advisable in the presence of a perforation, and it is beneficial for the surgeons to perform their routine method rather than a specific technique.

Randomized clinical trial of Appendicitis Inflammatory Response score-based management of patients with suspected appendicitis

BACKGROUND

The role of imaging in the diagnosis of appendicitis is controversial. This prospective interventional study and nested randomized trial analysed the impact of implementing a risk stratification algorithm based on the Appendicitis Inflammatory Response (AIR) score, and compared routine imaging with selective imaging after clinical reassessment.

METHOD

Patients presenting with suspicion of appendicitis between September 2009 and January 2012 from age 10 years were included at 21 emergency surgical centres and from age 5 years at three university paediatric centres. Registration of clinical characteristics, treatments and outcomes started during the baseline period. The AIR score-based algorithm was implemented during the intervention period. Intermediate-risk patients were randomized to routine imaging or selective imaging after clinical reassessment.

RESULTS

The baseline period included 1152 patients, and the intervention period 2639, of whom 1068 intermediate-risk patients were randomized. In low-risk patients, use of the AIR score-based algorithm resulted in less imaging (19·2 versus 34·5 per cent; P < 0·001), fewer admissions (29·5 versus 42·8 per cent; P < 0·001), and fewer negative explorations (1·6 versus 3·2 per cent; P = 0·030) and operations for non-perforated appendicitis (6·8 versus 9·7 per cent; P = 0·034). Intermediate-risk patients randomized to the imaging and observation groups had the same proportion of negative appendicectomies (6·4 versus 6·7 per cent respectively; P = 0·884), number of admissions, number of perforations and length of hospital stay, but routine imaging was associated with an increased proportion of patients treated for appendicitis (53·4 versus 46·3 per cent; P = 0·020).

CONCLUSION

AIR score-based risk classification can safely reduce the use of diagnostic imaging and hospital admissions in patients with suspicion of appendicitis. Registration number: NCT00971438 ( http://www.clinicaltrials.gov).

Dynamic properties of body plethysmographs and effects on physiological parameters

A model incorporating compliance, resistance, inertia, and the thermal time constant of plethysmographs is used to describe the effect of its dynamic properties on measured respiratory parameters. Using numerical simulation we studied the effect of distortion of flow signals from 13 infants in whom flow and esophageal pressure had been recorded. The distortion in amplitude, shape, and timing of the recorded flow patterns was dependent on the dynamic properties of the plethysmograph. For constant-volume "pressure" plethysmographs, errors of derived parameters such as compliance and resistance are very important if the thermal time constant is short. These errors are not corrected by calibrating the plethysmograph at the breathing frequency. Time correction of the flow signals in volume-displacement plethysmographs gives accurate results when the plethysmograph resistance and compliance are low. Overall, a volume-displacement plethysmograph with moderately high resistance of the flowmeter, corrected for internal pressure and inertia, gives the best possible results.

Mechanics of respiratory system in healthy anesthetized humans with emphasis on viscoelastic properties

The classic model of the respiratory system (RS) is comprised of a Newtonian resistor in series with a capacitor and a viscoelastic unit including a resistor and a capacitor. The flow interruption technique has often been used to study the viscoelastic behavior under constant inspiratory flow rate. To study the viscoelastic behavior of the RS during complete respiratory cycles and to quantify viscoelastic resistance (Rve) and compliance (Cve) under unrestrained conditions, we developed an iterative technique based on a differential equation. We, as others, assumed Rve and Cve to be constant, which concords with volume and flow dependency of model behavior. During inspiration Newtonian resistance (R) was independent of flow and volume. During expiration R increased. Static elastic recoil showed no significant hysteresis. The viscoelastic behavior of the RS was in accordance with the model. The magnitude of Rve was 3.7 +/- 0.7 cmH2O.l-1 x s, i.e., two times R. Cve was 0.23 +/- 0.051 l/cmH2O, i.e., four times static compliance. The viscoelastic time constant, i.e., Cve.Rve, was 0.82 +/- 0.11s. The work dissipated against the viscoelastic system was 0.62 +/- 0.13 cmH2O x 1 for a breath of 0.56 liter, corresponding to 32% of the total energy loss within the RS. Viscoelastic recoil contributed as a driving force during the initial part of expiration.

Reconstruction of the electrocardiogram during heart surgery

Electrocardiograms (ECG) recorded during arrhythmia surgery are used for identification of arrhythmias of different morphology. However, the interpretation of an intraoperative ECG is difficult because some leads cannot be recorded and the signals of the remaining leads often differ from those of a preoperative recording because of the sternotomy. Therefore, a method for reconstruction of a complete intraoperative ECG, which resembles a preoperatively recorded ECG, was studied in 24 patients undergoing heart surgery. The reconstruction method involves calculating coefficients for a transformation matrix, using a preoperative ECG recording and a first intraoperative ECG recording. Once this matrix has been established, further intraoperative recordings can be transformed into an ECG which strongly resembles a preoperative ECG. The correlation between reconstructed intraoperative leads and the corresponding preoperative leads was high in the leads Vx and Vy (median correlation coefficient 0.98 and 0.97) and slightly smaller in lead Vz (0.94). Further studies will prove if the method can be useful in arrhythmia surgery.