Abdominal wall hernia repair: a comparison of Permacol<Superscript>®</Superscript> and Surgisis<Superscript>®</Superscript> grafts in a rat hernia model

Background

This study compared two porcine-derived grafts Permacol (Tissue Science Laboratory, Covington, GA, USA) and Surgisis (Cook Surgical, Bloomington, IN, USA) in terms of strength of incorporation (SOI), incorporation of host tissue, and adhesion formation using a rat model.

Methods

A prospective randomized study using 48 Sprague–Dawley rats. A standardized 1.5 × 5 cm fascial defect was created and repaired with either Permacol or Surgisis grafts. The rats were then sacrificed at 3, 14, 28, or 60 days. The specimens were examined for SOI, neovascularization, collagen deposition, collagen organization, and adhesion formation.

Results

Surgisis had significantly greater SOI than Permacol at 28 (0.115 vs. 0.0754 Mpa) and 60 days (0.131 vs. 0.635 Mpa). Surgisis had significantly more collagen deposition and neovascularization than Permacol at 60 days. The area of adhesions was not significantly different between Surgisis and Permacol.

Conclusion

Surgisis is superior to Permacol in terms of SOI and tissue ingrowth at 60 days. Furthermore, Surgisis strengthened over time whereas Permacol decreased in strength.

     

The Lap-Band<Superscript>®</Superscript> System in a North American Population

Background: European and Australian results with laparoscopic adjustable gastric banding (LAGB) using the Lap-Band^? (Inamed Health, Santa Barbara, CA) have been impressive, with over 100,000 procedures completed at this writing. However, prior to U.S. FDA approval in June 2001, U.S. patients had to travel out of the U.S. for this procedure. This study reports on a series of U.S. patients who requested off-shore referral for LAGB placement. Methods: 105 U.S. patients were implanted with the Lap-Band System^? in Mexico by one surgeon in a private practice. 70% were implanted with the perigastric approach, while the final 30% were implanted using the pars flaccida approach. Routine postoperative visits, including band adjustments, were completed in a private U.S. clinic where medical staff performed frequent small adjustments as necessary to optimize results. Data were collected from concurrent and retrospective chart reviews and from telephone interviews. Summary statistics provided for baseline measures included mean ± standard deviation. Postoperative measures of weight loss included mean ± standard error. Results: Weight loss results were comparable to international results: 61% EWL at 12 months (n=50), 75% EWL at 24 months (n=37), 72% EWL at 36 months (n=24), and 60% EWL at 48 months (n=7). There were few major complications. Conclusion: Attention to patient management is essential to success, and this study found that appropriately-managed U.S. LAGB patients can be as successful as their international counterparts. Frequent follow-up delivered by a bariatric team with easy access to band adjustments is essential.     

NOTES<Superscript>®</Superscript> transgastric abdominal wall hernia repair in a porcine model

Introduction

With approximately 1 million ventral and inguinal hernia repairs performed in the United States each year, even small rates of complications translate into large numbers of patients. Less invasive approaches that potentially lower morbidity deserve consideration, recognizing there are many technical considerations that currently limit their use. We describe a reproducible technique and lessons learned in our laboratory that answer some existing questions with regards to the use of NOTES^® for hernia repair.

Methods

A non-survival porcine model with general anesthesia was utilized in all cases. Each animal underwent transgastric peritoneal access with a percutaneous endoscopic gastrostomy (PEG) technique, and the gastrotomy was dilated with a wire-guided balloon dilatation catheter. An Esophageal Z-stent delivery device (Cook Medical, Winston-Salem, NC) was modified ex-vivo to allow us to introduce and protect a 10 × 15 cm lightweight polypropylene hernia prosthetic with pre-placed sutures. Once deployed, the sutures were pulled through the abdominal wall using a looped spinal needle technique in combination with the flexible endoscope. After the four anchoring sutures were tied, proprietary endoscopically placed tacks (Cook Medical) were placed at regular intervals between the sutures to secure the edges of the prosthetic.

Results

Hernia repairs were performed on five animals. In each case, we successfully completed prosthetic delivery and deployment into the peritoneal cavity, anchoring to the abdominal wall with full-thickness abdominal wall sutures, and endoscopically placed nitinol tacks. All prosthetics were deployed flat against the anterior abdominal wall. Operative times ranged from 65 to 120 min.

Conclusion

Transgastric abdominal wall hernia repair is feasible, consistent, and reproducible. In particular, the delivery system can successfully deliver the prosthetic across the gastric wall via a transoral route. Survival animal experiments investigating outcomes related to quality of repair, microbiology, adhesions, and visceral closure need to be done. Human studies are not recommended until these issues are formally investigated.

     

<Superscript>1</Superscript>H MAS and <Superscript>1</Superscript>H → <Superscript>31</Superscript>P CP/MAS NMR Study of Human Bone Mineral

Chemical structure of human bone mineral was studied by solid-state nuclear magnetic resonance (NMR) with magic-angle spinning (MAS). Trabecular and cortical bone samples from adult subjects were compared with mineral standards: hydroxyapatite (HA), hydrated and calcined, carbonatoapatite of type B with 9 wt% of CO ₃ ^2– (CHA-B), brushite (BRU) and mixtures of HA with BRU. Proton spectra were acquired with excellent spectral resolution provided by ultra-high speed MAS at 40 kHz. 2D ¹H-³¹P NMR heteronuclear correlation was achieved by cross-polarization (CP) under fast MAS at 12 kHz. ³¹P NMR was applied with CP from protons under slow MAS at 1 kHz. Appearance of ³¹P rotational sidebands together with their CP kinetics were analyzed. It was suggested that the sidebands of CP spectra are particularly suitable for monitoring the state of apatite crystal surfaces. The bone samples appeared to be deficient in structural hydroxyl groups analogous to those in HA. We found no direct evidence that the HPO ₄ ^2– brushite-like ions are present in bone mineral. The latter problem is extensively discussed in the literature. The study proves there is a similarity between CHA-B and bone mineral expressed by their similar NMR behavior.     

Operative Experience and Follow-Up in a Cohort of Patients with a BMI ≥70 kg/m<Superscript>2</Superscript>

Background: Roux-en-Y gastric bypass (RYGBP) has been found to be a safe and effective operation for the morbidly obese whether performed open or laparoscopically. Weight loss has been substantial and sustained. Less is known about those at the extremes of obesity, with BMI ≥70 kg/m² with regard to safety and efficacy. This study is a retrospective review of a cohort of such patients, to examine operative experience and response to surgical treatment. Methods: A cohort of 34 patients who underwent open RYGBP at one institution was retrospectively reviewed. All operations were performed by a single surgeon. Operative outcome was examined, including early mortality, morbidity, need for intensive (ICU) care and hospital length of stay (LOS). Percent of excess weight lost (EWL) and percent reduction of BMI after at least 1 year of follow-up were determined. Late mortality was assessed. Results: There were 22 females and 12 males with mean age 42.0 + 8.1 years and mean BMI 78.3 + 8.5 kg/m². Obstructive sleep apnea (OSA) was found in 19/34 (58%) and hypoventilation syndrome of obesity (HSO) in 11/34 (32%). There was 1 early death (3 months) from renal failure. 7 patients (21%) developed complications, 3 major (pulmonary embolus, wound dehiscence) and 4 minor (wound infection). 16 patients (47%) required ICU, and 12 (35%) required extended mechanical ventilation. Hospital LOS was 10.3 ± 10.4 days for all patients. There were 4 late deaths (12%) from 7 to 36 months after RYGBP. Mean percent EWL was 61 ± 17 and mean percent reduction in BMI was 44 ± 11. For those followed at least 36 months, weight loss was sustained in 12/14 patients. Conclusions: RYGBP can be performed safely, even at the extremes of weight. While technically challenging, there were no instances of intra-abdominal sepsis. Postoperative complications were few. Need for ICU and hospital LOS is greater, reflecting the incidence of pre-existing pulmonary problems. Weight loss is significant and appears to be sustained in most patients. Late deaths have been noted and deserve careful scrutiny.     

Self-pressurized air-Q<Superscript>®</Superscript> intubating laryngeal airway <Emphasis Type="Italic">versus</Emphasis> the LMA<Superscript>®</Superscript> Classic™: a randomized clinical trial

Purpose

The self-pressurized air-Q® (air-Q SP) intubating laryngeal airway is a relatively new supraglottic airway (SGA) device. The intracuff pressure of air-Q dynamically equilibrates with the airway pressure and adjusts to the patient’s pharyngeal and periglottic anatomy, potentially providing improved airway fit and seal. The aim of this prospective randomized study was to compare the clinical performance of air-Q to the LMA® Classic? SGA.

Methods

Adult patients requiring general anesthesia for elective surgery were prospectively enrolled and randomly assigned to either air-Q SP or the LMA Classic SGA. Oropharyngeal leak pressure (primary endpoint), success rate, insertion features (insertion time, ease of insertion, requirement for device manipulation), sealing function, gastric insufflation, bronchoscopic view, and oropharyngeal complications at device insertion and following its removal (sore throat, dysphagia, dysphonia) were compared.

Results

The mean (standard deviation [SD]) oropharyngeal leak pressure just after insertion was similar in the air-Q SP and LMA [16.8 (4.9) vs 18.6 (5.5) cm H₂O, respectively; mean difference, 1.8 cm H₂O; 95% CI, ?0.5 to 4.2; P = 0.13] and did not differ at ten minutes following device insertion. Median [interquartile range (IQR)] peak inspiratory pressure just after insertion was lower in the air-Q SP (11.0 [10.0-13.0] vs 13.0 [11.0-14.0] cmH₂O, median difference, 1.0 cm H₂O; 95% CI, 0.0 to 2.0; P = 0.03) but no difference was observed at ten minutes. The median [IQR] insertion time was faster with the air-Q SP (15.9 [13.6-20.3] sec vs 24 [21.2-27.1] sec; median difference, 8.1 sec; 95% CI, 5.6 to 9.9; P < 0.001) and improved bronchoscopic viewing grade were seen with the air-Q SP immediately after insertion (P < 0.001). No differences between the groups were observed with respect to the rate of successful insertion at first attempt, overall insertion success rate, ease of insertion, and complications.

Conclusions

The air-Q SP had similar leak pressures but a faster insertion time and superior bronchoscopic viewing grade when compared with the LMA Classic. The air-Q SP is a suitable alternative to the LMA Classic in adult patients and may be a superior conduit for tracheal intubation.

Trial registration

www.clinicaltrials.gov (NCT02206438). Registered 1 August 2014.

     

Na<Superscript>+</Superscript>, K<Superscript>+</Superscript>, Cl<Superscript>−</Superscript>, acid–base or H<Subscript>2</Subscript>O homeostasis in children with urinary tract infections: a narrative review

Guidelines on the diagnosis and management of urinary tract infections in childhood do not address the issue of abnormalities in Na⁺, K⁺, Cl^? and acid–base balance. We have conducted a narrative review of the literature with the aim to describe the underlying mechanisms of these abnormalities and to suggest therapeutic maneuvers. Abnormalities in Na⁺, K⁺, Cl^? and acid–base balance are common in newborns and infants and uncommon in children of more than 3 years of age. Such abnormalities may result from factitious laboratory results, from signs and symptoms (such as excessive sweating, poor fluid intake, vomiting and passage of loose stools) of the infection itself, from a renal dysfunction, from improper parenteral fluid management or from the prescribed antimicrobials. In addition, two transient renal tubular dysfunctions may occur in infants with infectious renal parenchymal involvement: a reduced capacity to concentrate urine and pseudohypoaldosteronism secondary to renal tubular unresponsiveness to aldosterone that presents with hyponatremia, hyperkalemia and acidosis. In addition to antimicrobials, volume resuscitation with an isotonic solution is required in these children. In secondary pseudohypoaldosteronism, isotonic solutions (such as 0.9 % saline or lactated Ringer) correct not only the volume depletion but also the hyperkalemia and acidosis. In conclusion, our review suggests that in infants with infectious renal parenchymal involvement, non-renal and renal causes concur to cause fluid volume depletion and abnormalities in electrolyte and acid–base balance, most frequently hyponatremia.     

Die Bedeutung des Advanced Trauma Life Support<Superscript>®</Superscript> (ATLS<Superscript>®</Superscript>) im Schockraum

INTRODUCTION: There is clinical evidence, that a standardized management of trauma patients in the emergency room improves outcome. METHODS: The ATLS training course teaches a systematic approach to the trauma patient in the emergency room. The aim is a rapid and accurate assessment of the patient's physiologic status, the treatment according to priorities and the decision making if transfer to a trauma center is necessary. The German Trauma Society has taken over the course concept from the American College of Surgeons (ACS) and is authorized to organize ATLS courses in Germany. RESULTS: A standardized management in the emergency room helps to prevent secondary injury, to realize timing as a relevant factor in the initial treatment and to assure a high standard of care. The ATLS course provides the participant with knowledge, skills and attitudes and is open to doctors of all specialties involved in the initial management of severely injured patients. CONCLUSION: ATLS teaches a standardized and established approach to the trauma patient in the emergency room. It has been transferred to 46 countries and the content is reviewed regularly to consider new scientific evidence. Germany has the chance to participate in this international standard of care and to introduce own experiences into the review process.     

Initial experiences with the Hemopatch<Superscript>®</Superscript> as a hemostatic agent in zero-ischemia partial nephrectomy

Purpose

Nephron-sparing surgery (NSS) is the gold standard treatment for resectable renal tumors. In the last decade, laparoscopic partial nephrectomy (LPN) has evolved in technical, surgical and oncological aspects and is an accepted treatment option for local-stage renal tumors. Improvements in not only surgical techniques, but also potent hemostats have encouraged this evolution. Here, we report our initial experiences with a new hemostatic agent, Hemopatch^® (polyethylene glycol-coated collagen patch, Baxter), in zero-ischemia LPN.

Methods

Seven patients with confirmed renal masses were enrolled and subjected to zero-ischemia LPN. In all cases, Hemopatch^® was applied to the tumor resection site after suturing of the renal parenchyma. The following clinical data were captured for analysis: staging information, PADUA and RENAL nephrometry scores, operation time, blood loss, complications, pathology and hospitalization length.

Results

The median tumor size was 30.0 mm (range 9.5–72). The median PADUA and RENAL nephrometry scores were 6 (range 6–7) and 4 (range 4–6), respectively. All LPNs were performed with the zero-ischemia technique. In six of the seven patients, parenchymal suturing of the resection site was performed. No uncontrolled bleeding was observed. The median operation duration was 139 min (range 103–194), the median blood loss was 325 cc (range 50–700) and the median hospitalization length was 6 days (range 4–7). Hemopatch^® provided sufficient hemostasis in all cases. No postoperative complications were observed.

Conclusions

Although this study is limited to a small set of initial experiences with Hemopatch^® in LPN, it proves the feasibility and reliability of this new hemostat. Following further evaluation in prospective randomized comparative studies, Hemopatch^® might represent a promising tool in NSS.

     

Watertightness and Effectiveness of a Fibrinogen-Based Collagen Fleece (TachoComb<Superscript>®</Superscript>) in Neurosurgery

Summary BACKGROUND: Meningitis or cerebrospinal fluid rhinorrhoea can occur years or even decades after trauma or operation and can be the first indication of a previously unidentified dural lesion. Preventing cerebrospinal fluid (CSF) leakage with a fibrinogen-based collagen fleece (TachoComb^®) was the interest of our clinical study. METHODS: In the present study, we examined the watertightness and effectiveness of TachoComb^® following supratentorial/infratentorial as well as skull-base operations. The dura was closed primarily by sutures and covered with a fibrinogen-based collagen fleece to prevent CSF leakage. RESULTS: Twelve patients developed a subcutaneous CSF collection requiring no further treatment, seven patients were managed by lumbar CSF drainages, and three patients had to be reoperated. CONCLUSIONS: Based on these results, we proved the watertightness and effectiveness of this fibrinogen-based collagen fleece.     

Off-pump hemostasis for left ventricular rupture after myocardial infarction with Hydrofit<Superscript>®</Superscript> and Surgicel<Superscript>®</Superscript>

Left ventricular free wall rupture (LVFWR) is a catastrophic complication of myocardial infarction. In these cases, cardiopulmonary bypass (CPB) should be performed for left ventricular repair, but can impact hemodynamic stability. An 87-year-old man presented with acute shock. He was diagnosed with LVFWR after myocardial infarction. We describe a simple, effective, and reproducible technique to achieve hemostasis at the LVFWR site during emergency operation using Hydrofit^® and Surgicel^® surgical hemostatic agents. We simply placed and manually pressed the Hydrofit^® and Surgicel^® composite on the bleeding site. This technique provides complete hemostasis without CPB establishment.     

Regulatory mechanism of “K<Superscript>+</Superscript>-recycling” for Na<Superscript>+</Superscript>-reabsorption in renal tubules

Hypertension is one of the predominant risk factors for the progression of renal impairment, and the most common disorder in industrialized societies. Because reduction of the systemic blood pressure in hypertension can halt the progression of renal impairment, it is imperative to appropriately control the systemic blood pressure. Recent genetic analysis has reconfirmed that renal maladjustment of Na⁺-homeostasis, which determines the extracellular fluid volume, is a key element in the pathogenesis of hypertension. The distal tubules adjust the net Na⁺-excretion according to Na⁺-ingestion and maintain the Na⁺-homeostasis. The distal convoluted tubules and the connecting tubules are the predominant sites for the adjustment in individuals with a modern lifestyle. In these tubules, Na⁺-reabsorption depends on “K⁺-recycling”, which is conducted through K⁺ channels. Because the functional expression of K⁺ channels in these tubules is regulated by signal motifs for intracellular localization, the adjustment of “K⁺-recycling” through the modification of signal motifs could be a new target for the treatment of hypertension.     

Laparoscopic Management of Lap-Band<Superscript>®</Superscript> Slippage

Background. The Lap-Band^? is generally associated with a low morbidity rate. Although gastric slippage through the band remains a concern, the rate has diminished with new band placement techniques. Methods. Between November 2000 and June 2002, 198 Lap-Band? Systems were inserted in patients in the Houston, Texas, area. 4 of these patients, plus an additional patient whose Lap-Band^? had been inserted by another surgeon, developed slippages, and in each case the gastric slip was corrected and the band was salvaged and repositioned laparoscopically. To facilitate dissection and repositioning of the band in 3 of these patients, the band had to be unlocked using a simple laparoscopic technique. Results. All patients were discharged the morning following surgery with no complications and good position of the band as evidenced by esophagogram study and resolution of symptoms. After 2 to 12 months follow-up, all 5 patients remain symptom-free and continue to lose weight. Conclusions. Gastric slippage with the Lap-Band^? can be managed by laparoscopic salvage and repositioning of the slipped band.     

Surgical technique: about a new total and isoelastic wrist implant (Prosthelast<Superscript>®</Superscript>)

This study describes a new total wrist implant (Prosthelast^®) designed to reduce the risk of distal migration of the carpal component. The Prosthelast^® implant consists in a one-block radial implant replacing the metaphysis and the articular surface fixed to a radial elastic centromedullar wire and a carpal component in titanium with an articular condylar surface in polyethylene. We operated on five patients (three male patients and two female patients) and followed them up for 12 months on average. Two of the patients presented with rheumatoid arthritis of the wrist, and an ulnar osteotomy (Darrach procedure) was carried out at the same time of the arthroplasty. All clinical variables improved postoperatively (Quick DASH score, pain score, range of motion) except from wrist flexion which was reduced. No patients underwent revision surgery. Two patients presented with a periprosthetic radiolucent loosening around the radial component, but no implant migration was observed. Overall, the preliminary results of our case series show that the new Prosthelast^® implant presents comparable short-term results to those described in the literature. We will follow up the patients to verify that long-term results are as satisfactory as the short-term results.     

Epidrum<Superscript>®</Superscript>: a new device to identify the epidural space with an epidural Tuohy needle

Epidrum^® is an optimal pressure, loss of resistance device for identifying the epidural space. We investigated the usefulness of Epidrum versus the loss of resistance or hanging drop techniques while performing epidural anesthesia. Eighty adult patients who were scheduled for elective surgery under lumbar epidural anesthesia were randomized into two groups. The first group (Epidrum group) consisted of 40 adult patients who were scheduled for epidural anesthesia using Epidrum. The second group (control group) consisted of 40 adult patients who were scheduled for epidural anesthesia using the loss of resistance or hanging drop technique. We recorded the time required to identify the epidural space and outcomes of epidural catheterization. The attending anesthesiologists were also questioned regarding the ease of control of the Tuohy needle and of epidural space identification with each method. The time required to perform epidural anesthesia was significantly shorter in the Epidrum group than in the control group [28 s (10–76) vs. 90 s (34–185); median (interquartile range)] (p < 0.05). Tuohy needle control was significantly easier in the Epidrum group than in the control group (p < 0.05). Epidrum is useful for performing epidural anesthesia quickly while obtaining good Tuohy needle control.     

Accuracy of screw fixation using the O-arm<Superscript>®</Superscript> and StealthStation<Superscript>®</Superscript> navigation system for unstable pelvic ring fractures

Purpose

Screw fixation for unstable pelvic ring fractures is generally performed using the C-arm. However, some studies reported erroneous piercing with screws, nerve injuries, and vessel injuries. Recent studies have reported the efficacy of screw fixations using navigation systems. The purpose of this retrospective study was to investigate the accuracy of screw fixation using the O-arm^® imaging system and StealthStation^® navigation system for unstable pelvic ring fractures.

Methods

The participants were 10 patients with unstable pelvic ring fractures, who underwent screw fixations using the O-arm StealthStation navigation system (nine cases with iliosacral screw and one case with lateral compression screw). We investigated operation duration, bleeding during operation, the presence of complications during operation, and the presence of cortical bone perforation by the screws based on postoperative CT scan images. We also measured the difference in screw tip positions between intraoperative navigation screen shot images and postoperative CT scan images.

Results

The average operation duration was 71 min, average bleeding was 12 ml, and there were no nerve or vessel injuries during the operation. There was no cortical bone perforation by the screws. The average difference between intraoperative navigation images and postoperative CT images was 2.5 ± 0.9 mm, for all 18 screws used in this study.

Conclusion

Our results suggest that the O-arm StealthStation navigation system provides accurate screw fixation for unstable pelvic ring fractures.