Robotic Heller's myotomy using the new Hugo™ RAS system: first worldwide report

BACKGROUND

Achalasia is a rare disorder of the esophagus characterized by motor dysfunction in the esophagus and relaxation failure of the lower esophageal sphincter (LES). Currently, surgical myotomy procedures are considered the standard of care. Robotic Heller's myotomy (RHM) with fundoplication has been gaining popularity due to documented advantages in the precision of myotomy as well as avoiding the potential reflux following per-oral endoscopic myotomy (POEM). To the best of our knowledge, RHM has thus far has been performed exclusively by the da Vinci surgical system. The new Hugo RAS™ system offers a unique modular design and an open console which offers better maneuverability and docking options. In this study, we present the first worldwide series of patients undergoing RHM using the new Hugo RAS™ platform. Our objective is to propose optimal operating configuration and setup to fully harness the advantages of the unique modular design of this system.

METHODS

Ten consecutive achalasia patients underwent Robotic Heller's myotomy (RHM) with the Hugo RAS™ system. We prospectively collected patient data, including demographics, comorbidities, ASA class, Eckardt scores, pre-operative manometric data, and EndoFlip parameters. Additionally, we recorded the docking and total operative times.

RESULTS

Between December 2022 and August 2023, 10 patients underwent RHM with the Hugo™ RAS system. Patients had a median age of 42.5 years, 60% were female, and mean BMI was 23.2. Fifty percent had achalasia type 2 and 50% type 1. The median pre-operative integrated relaxation pressure (IRP) was 24.9. Median docking time was 10 min and overall operative time was 129.5 min. All patients, except one with acute coronary syndrome, had an uneventful peri-operative course and were discharged on post-operative day 2.

CONCLUSION

The Hugo™ RAS system is well designed for robotic Heller myotomy. The operative and clinical results are similar to the currently used robotic system; however, the modular design of the system has some differences. These translate to better docking angles and maneuverability as well as console surgeon's ergonomics. Further experience is needed to explore the advantages of the system's modular design and function.

The Angle of His as a Measurable Element of the Anti-reflux Mechanism

BACKGROUND

Gastroesophageal reflux disease (GERD) is a common condition, resulting from the loss of the anti-reflux barrier. Laparoscopic fundoplication is the surgical procedure of choice for treatment of GERD; however, there remains a debate on the exact mechanism through which it prevents reflux.

OBJECTIVES

Our aim was to understand the relationship between reflux, fundoplication, and the angle of His on an experimental model.

METHODS

The study was conducted on four groups of fresh explanted swine stomachs: control group, myotomy, myotomy with Nissen fundoplication, and myotomy with Toupet fundoplication. The stomachs were placed in a specially designated container on an inclinable platform which would increase the hydrostatic pressure on the esophago-gastric junction. Measurements of the angle of His using fluoroscopy and the esophago-gastric orifice area using endoscopy were performed, and the occurrence of reflux was documented.

RESULTS

Each group of the study contained nine swine stomachs. In the control and myotomy groups, the angle became wider as the incline level increased the pressure and was significantly different between the groups (p < .001). Both groups demonstrated an increase in the orifice area as the incline level increased the pressure. There was a significant correlation between the angle of His and the area of the esophago-gastric orifice (p < .001). In the control group, the reflux began at the 0°. In the myotomy group, it began at the + 15° incline (less pressure). Reflux rarely occurred in the Nissen and Toupet groups, with the breaking point being mostly defined as "beyond - 30°". A significant difference was noted in the occurrence of reflux between fundoplication and the non-fundoplication groups (p < 0.001), while there was no significant difference between the Toupet and Nissen groups (p = 0.134). Analysis showed a significant independent correlation between both the angle of His and the orifice area with the presence of reflux (p = .002 and p = .024 respectively).

CONCLUSIONS

In this study, we developed an experimental model to enable careful evaluation of the elements of the anti-reflux mechanism, of which, the angle of His has a measurable element. We demonstrated that as the angle of His becomes wider the esophago-gastric orifice area becomes larger. Additionally, a wider angle of His and a larger esophago-gastric orifice area were correlated independently with more reflux. This suggests that the fundoplication creates an acute angle of His which is correlated with a smaller area of the esophago-gastric orifice and eventually with a lower incidence of reflux.

Post-POEM Contrast-Enhanced Swallow Study: Is It Always Necessary?

BACKGROUND

Peroral endoscopic myotomy (POEM) is rapidly becoming the procedure of choice for treating esophageal achalasia. In most centers, contrast-enhanced swallow studies (CESS) are routinely performed postoperatively to confirm mucosal integrity. The aim of this study was to determine the necessity of performing these studies routinely after POEM.

METHODS

A retrospective review of a prospectively maintained database of patients who underwent POEM between December 2012 and November 2020 was performed. All patients underwent a CESS on the first postoperative day. Medical records including vital signs, complete blood count, and POD-1 CESS were evaluated.

RESULTS

One hundred thirty-four consecutive patients were included in the study. Sixty-nine (51.49%) CESS showed abnormal findings; while most findings did not change the postoperative course, five (7.2%) demonstrated tunnel leaks, which did alter the overall management. Screening patients for fever, tachycardia, or leukocytosis on POD-1 had a 100% sensitivity and a 62% specificity for finding a clinically significant complication on CESS.

CONCLUSIONS

The study findings suggest that performing routine contrast-enhanced swallow studies on all patients is not necessary following POEM, as leaks can be screened for by clinical or laboratory abnormalities. Herein, we propose an algorithm based on objective measurable findings for the selection of patients who should undergo CESS.

OC-002 EVALUATION OF GIANT INGUINAL HERNIA REPAIR RESULTS - A RETROSPECTIVE SINGLE INSTITUTION CASE-CONTROL PROPENSITY SCORE MATCHED STUDY

Background

Giant inguinal hernia (GIH), defined as a hernia descending below the inner-thigh midpoint in upright position, is rare. Case reports describe techniques in which the abdominal cavity is prepared and care is taken to prevent abdominal compartment syndrome (ACS). Our aim was to analyze and review our experience with GIH repair.

Methods

Retrospective single-institution, case-control, study included adults who underwent GIH repair between 2014–2021 at an university referral center. Technique included endo-tracheal intubation, head-down positioning, maximal pre-incision reduction of hernia contents, and repair with mesh. Follow-up was conducted in outpatient clinic. Results were compared to a time-based control group.

Results

During the study period, 58 patients underwent an open GIH repair with mesh without abdominal preparation. Control group included 232 patients who underwent open non-giant inguinal hernia repair (control group). Bowel resection was not necessary in any case. The in-hospital and 30-day complication rates were 17.2% and 68.9% in the GIH group, and 8.2% and 27.2%, in the control group (p=0.04, OR=2.3; and p&lt;0.001, OR=5.9, respectively). Ischemic orchitis was common in the GIH group (65.5%) compared to the control group (13.4%) (p&lt;0.001, OR=12.3). ACS, major complications and mortality were not reported. 90-day complication rates were similar. 2 cases of recurrence (0.9%) were observed in the control group.

Conclusions

Our study suggests that GIH repair is safe and feasible, and there is no need for abdominal cavity preparation. Early complications, mainly ischemic orchitis, are more common than control group, but without long-term implications and with a very low recurrence rate.

Pediatricians as Case Managers Reduce the Exposure to Computerized Tomography in Children Experiencing Minor Head Trauma

BACKGROUND

Head trauma is one of the most common reasons for pediatric emergency medicine department (PED) visits. Computerized tomography (CT) scan is considered the criterion standard for the diagnosis of traumatic brain injury but was shown to increases the risk of malignancies.

METHODS

We retrospectively analyzed collected data of all children (ages 0-16 years) experiencing mild head trauma who were admitted to a single center, from January 1, 2010, to December 31, 2015. Comparison between patients treated by pediatricians/pediatric emergency medicine physicians (PEMP) with those treated by surgeons regarding CT rates and prognosis was done.

RESULTS

During the previously mentioned period, 4232 children presented to the PED after minor head trauma, the average age was 5.4 (±4) years and 67.1% were male. Head CT was done in 7.7%, of which 30.7% had positive findings. Younger children tended to have higher percentage of positive findings on CT scan (60%, 43.8%, 26.6%, P = 0.003, for children up to 5 months, 5-24 months, and older than 24 months, respectively). Pediatricians ordered less CT scans when compared with surgeons (5.4% vs 8.5%, P < 0.001). Moreover, they had higher rates of positive findings on CT scan (52.5% vs 25.8%, P < 0.001). When all other characteristics were similar, if the case manager was a pediatrician, the patient's chances to undergo a CT scan were 4.3 times lower than if the case manager was a surgeon (odds ratio, 4.277; confidence interval, 2.274-7.104). No difference in readmissions or other complications were found between the 2 groups.

DISCUSSION

This study highlights that when the case manager of children with minor head trauma is a pediatrician/PEMP, CT scan rates and thus exposure to radiation are diminished without a failure to detect clinically important traumatic brain injury.In conclusion, our findings suggest that when possible, all children experiencing minor head trauma should be treated by a pediatrician/PEMP in the PED.

Molecular epidemiology of Mycobacterium tuberculosis infection in Israel

Restriction fragment length polymorphism analysis with IS6110 and DR-r probes was used to study 69 Mycobacterium tuberculosis isolates obtained from Israeli patients and new immigrants from the former Soviet Union and Ethiopia. DNA fingerprinting identified unique patterns for almost all isolates, indicating that most patients were infected with a unique strain imported from their country of origin and that their latent infection was reactivated in Israel.

AaIT: from neurotoxin to insecticide

AaIT is a single chain neurotoxic polypeptide derived from the venom of the Buthid scorpion Androctonus australis Hector, composed of 70 amino acids cross-linked by four disulfide bridges. Its strict selectivity for insects has been documented by toxicity, electrophysiological and ligand receptor binding assays. These last have shown that various insect neuronal membranes possess a single class of non-interacting AaIT binding sites of high affinity (K(D) = 1-3(n)M) and low capacity (0.5-2.0 pmol/mg prot.). The fast excitatory paralysis induced by AaIT is a result of a presynaptic effect, namely the induction of a repetitive firing in the terminal branches of the insect's motor nerves resulting in a massive and uncoordinated stimulation of the respective skeletal muscles. The neuronal repetitive activity is attributed to an exclusive and specific perturbation of sodium conductance as a consequence of toxin binding to external loops of the insect voltage-dependent sodium channel and modification of its gating mechanism. From a strictly agrotechnical point of view AaIT involvement in plant protection has taken the following two complementary forms: firstly, as a factor for the genetic engineering of insect infective baculoviruses resulting in potent and selective bio-insecticides. The efficacy of the AaIT-expressing, recombinant baculovirus is attributed mainly to its ability to continuously provide and translocate the gene of the expressed toxin to the insect central nervous system; secondly, based on the pharmacological flexibility of the voltage-gated sodium channel, as a device for insecticide resistance management. Channel mutations conferring resistance to a given class of insecticidal agents (such as the KDR phenomenon) may greatly increase susceptibility to the AaIT expressing bioinsecticides. Thus the AaIT is a pharmacological tool for the study of insect neuronal excitability and chemical ecology and the development of new approaches to insect control.

Fate of new neurons in adult canary high vocal center during the first 30 days after their formation

Projection neurons are added to the high vocal center (HVC) of adult songbirds. Here we report on events associated with their initial arrival in HVC. Neurons formed in adult canaries were labeled with [(3)H]-thymidine and examined 8, 15, 22, and 31 days later. By 8 days, some [(3)H]-labeled cells with the nuclear profile of postmigratory neurons were already present in HVC but could not be retrogradely labeled by Fluoro-Gold injections in the robust nucleus of the archistriatum (RA); 7 days later, a few such cells could be backfilled from RA. Thus, new neurons may arrive in HVC as much as 1 week prior to establishing connections with RA. By 31 days, 43% of the [(3)H]-labeled neurons could be backfilled from RA. In no case were new neurons backfilled by tracer injections into Area X, suggesting that newly formed HVC cells do not establish a transient connection with this region. At all survival times, the somata of new neurons were often clustered tightly together with other HVC neurons that differed in age and projection. Between days 15 and 25 after their birth, half of the new HVC neurons disappeared. We conclude: (1) that neurons arrive in HVC earlier than previously thought, (2) that soon after their arrival they become part of cell clusters in HVC, and (3) that in addition to the previously described death of new neurons that occurs over a period of months, there is an early wave of death that occurs soon after new neurons adopt a postmigratory phenotype.

Delayed-type hypersensitivity activity of the Brucella L7/L12 ribosomal protein depends on posttranslational modification

The ribosomal protein L7/L12 isolated from Brucella melitensis induces a delayed-type hypersensitivity (DTH) reaction in brucella-sensitized guinea pigs. Surprisingly, the recombinant brucella L7/L12 protein expressed in Escherichia coli as a fusion protein with a six-histidine tag cannot elicit such a reaction. The six histidines tagged to the recombinant L7/L12 protein were removed enzymatically, but the resulting protein did not induce a DTH reaction in sensitized animals. Incubation of the recombinant L7/L12 fusion protein in a B. melitensis lysate endowed the recombinant protein with a DTH activity, suggesting that the recombinant protein was modified by this treatment. Glycosylation or phosphorylation of the recombinant L7/L12 protein could not be detected. On the other hand, radiolabeled palmitic acid was found to be incorporated to the recombinant protein during its incubation in the brucella lysate. This incorporation was specific for the brucella L7/L12 protein and was inhibited when the brucella lysate was frozen and thawed before the incubation. The data reported here indicate that posttranslational modification of L7/L12 protein comprising at least an acylation step is required for the brucella L7/L12 DTH activity.

Cloning of the gene encoding streptococcal immunoglobulin A protease and its expression in Escherichia coli

We have identified and cloned a 6-kilobase-pair segment of chromosomal DNA from Streptococcus sanguis ATCC 10556 that encodes immunoglobulin A (IgA) protease activity when cloned into Escherichia coli. The enzyme specified by the iga gene in plasmid pJG1 accumulates in the periplasm of E. coli MM294 cells and has a substrate specificity for human IgA1 identical to that of native S. sanguis protease. Hybridization experiments with probes from within the encoding DNA showed no detectable homology at the nucleotide sequence level with chromosomal DNA of gram-negative bacteria that excrete IgA protease. Moreover, the S. sanguis iga gene probes showed no detectable hybridization with chromosomal DNA of S. pneumoniae, although the IgA proteases of these two streptococcal species cleaved the identical peptide bond in the human IgA1 heavy-chain hinge region.

Preferential suppression of normal exoenzyme formation by membrane-modifying agents

Cerulenin, phenethyl alcohol, benzyl alcohol, procaine, and a series of aliphatic alcohols selectively suppressed production of active exoenzymes by various bacterial strains.

Evidence linking penicillinase formation and secretion to lipid metabolism in Bacillus licheniformis

The formation of penicillinase by cultures of Bacillus licheniformis was preferentially suppressed by cerulenin, an antibiotic known to specifically inhibit fatty acid synthesis in microorganisms. The effect was studied at cerulenin concentrations that had almost no effect on the rate of cell growth and overall protein synthesis, but that reduced the rate of [14C]acetate incorporation (by 50 to 70%), indicating partial inhibition of lipid synthesis. The levels of both the released enzyme (exopenicillinase) and its cell-bound precursor were reduced to the same extent (70% to 80%). Enzyme formation was gradually resumed after the removal of cerulenin or the addition of a mixture of fatty acids prepared from lipids extracted from B. licheniformis. Reversal was less effective as the time interval between treatment with cerulenin and addition of fatty acids increased. We conclude that de novo synthesis of fatty acids is required for the formation of both the membrane-bound and extracellular penicillinase. Suppression of the membrane-bound enzyme is a likely consequence of the altered membrane (decreased lipid-to-lipid ratio and increased density) seen in cerulenin-treated preparations. The corresponding suppression of exopenicillinase is consistent with the view that it is derived from the membrane-bound form. A mechanism linking the general class of exportable proteins to specific aspects of lipid synthesis is discussed.