Comparison of postoperative hepatic function after laparoscopic versus open gastric bypass

Low- versus standard- pneumoperitoneum in patients undergoing robot-assisted radical prostatectomy: a randomised, triple-blinded study

OBJECTIVE

To investigate the effectiveness and impact of low-pressure pneumoperitoneum (Pnp) on postoperative quality of recovery (QoR) and surgical workspace (SWS) in patients with prostate cancer undergoing robot-assisted radical prostatectomy (RARP).

PATIENTS AND METHODS

A randomised, triple-blinded trial was conducted in a single centre in Denmark from March 2021 to January 2022. A total of 98 patients with prostate cancer undergoing RARP were randomly assigned to either low-pressure Pnp (7 mmHg) or standard-pressure Pnp (12 mmHg). Co-primary outcomes were postoperative QoR measured via the QoR-15 questionnaire on postoperative Day 1 (POD1), POD3, POD14, and POD30, and SWS assessed intraoperatively by a blinded assessor (surgeon) via a validated SWS scale. Data analysis was performed according to the intention-to-treat principle.

RESULTS

Patients who underwent RARP at low Pnp pressure demonstrated better postoperative QoR on POD1 (mean difference = 10, 95% confidence interval [CI] 4.4-15.5), but no significant differences were observed in the SWS (mean difference = 0.25, 95% CI -0.02 to 0.54). Patients allocated to low-pressure Pnp experienced statistically higher blood loss than those in the standard-pressure Pnp group (mean difference = 67 mL, P = 0.01). Domain analysis revealed significant improvements in pain (P = 0.001), physical comfort (P = 0.007), and emotional state (P = 0.006) for patients with low-pressure Pnp. This trial was registered at ClinicalTrials.gov, NCT04755452, on 16/02/2021.

CONCLUSION

Performing RARP at low Pnp pressure is feasible without compromising the SWS and improves postoperative QoR, including pain, physical comfort, and emotional state, compared to the standard pressure.

Intravenous Arginine Administration Attenuates the Inflammatory Response and Improves Metabolic Profiles in Diet-Induced Obese Mice after Sleeve Gastrectomy

Sleeve gastrectomy (SG) is a bariatric surgery that can effectively reduce weight and improve obesity-associated comorbidities. However, surgical stress intensifies inflammation and imbalanced metabolic profiles. Arginine (Arg) is a nutrient with immunomodulatory and anti-inflammatory properties. This study evaluated the short-term effects of Arg administration on adipocyte inflammation and metabolic alterations in obese mice after SG. Mice were assigned to normal and high-fat diet (HFD) groups. After 16 weeks, the HFD group were divided to sham (SH), SG with saline (SS), or Arg (SA) groups. SS and SA groups were postoperatively injected with saline or Arg via the tail vein and sacrificed at day 1 or 3 after the SG, respectively. Results showed that obesity caused elevated plasma glucose and leptin levels. The SG operation enhanced the expression of inflammatory cytokines and macrophage infiltration in adipose tissues, whereas hepatocyte gene expressions associated with lipid β-oxidation were downregulated. Arg treatment reversed the expressions of β-oxidation-associated genes and reduced lipid peroxide production in the liver. Additionally, adipose tissue expressions of inflammatory chemokines were reduced, while the M2 macrophage marker increased after surgery. The findings suggest that postoperative Arg administration elicited more balanced hepatic lipid metabolism, polarized macrophages toward the anti-inflammatory type, and attenuated adipocyte inflammation shortly after SG.

Comparison of Short-Term Outcomes Between Hand-assisted Laparoscopic Distal Gastrectomy and Laparoscopy-assisted Distal Gastrectomy in Gastric Cancer

Hand-assisted laparoscopic surgery is considered to provide the benefits of laparoscopic surgery in various diseases. However, limited information is available regarding the feasibility of hand-assisted laparoscopic distal gastrectomy (HALDG)-a subset of hand-assisted laparoscopic surgery-as a gastric cancer treatment. This study aimed to evaluate the usefulness of HALDG compared with laparoscopy-assisted distal gastrectomy (LADG). Consecutive patients who underwent HALDG (n=58) or LADG (n=90) for stage I gastric cancer between 2005 and 2016 were eligible. Operative time was significantly shorter and blood loss was significantly higher in HALDG than in LADG (P<0.001, both). Postoperative aminotransferase levels were significantly lower in HALDG than in LADG (P<0.001). There was no significant difference in perioperative complications, a number of analgesics, postoperative C-reactive protein levels, and 3-year relapse-free and overall survival rates between the groups. This study suggests that HALDG is a safe and feasible approach and could become an effective option for stage I gastric cancer treatment.

Intravenous Glutamine Administration Improves Glucose Tolerance and Attenuates the Inflammatory Response in Diet-Induced Obese Mice after Sleeve Gastrectomy

Obesity is a health problem associated with many metabolic disorders. Weight reduction can effectively alleviate obesity-associated complications. Sleeve gastrectomy is a commonly used bariatric surgery and is considered safe and effective for improving outcomes. Glutamine (GLN) is an amino acid with anti-oxidative and anti-inflammatory properties. This study used a mouse model of sleeve gastrectomy to investigate the impacts of intravenous GLN administration on glucose tolerance and adipocyte inflammation short-term after surgery. C57BL6 male mice were divided into normal control (NC) and high-fat diet groups. The high-fat diet provided 60% of energy from fat for 10 weeks to induce obesity. Mice fed the high-fat diet were then assigned to a sham (SH) or sleeve gastrectomy with saline (S) or GLN (G) groups. The S group was intravenously injected with saline, while the G group was administered GLN (0.75 g/kg body weight) via a tail vein postoperatively. Mice in the experimental groups were sacrificed on day 1 or 3 after the surgery. Results showed that obesity resulted in fat accumulation, elevated glucose levels, and adipokines production. Sleeve gastrectomy aggravated expressions of inflammatory cytokine and macrophage infiltration markers, cluster of differentiation 68 (CD68), epidermal growth factor-like module-containing mucin-like hormone receptor-like 1 (EMR-1), and macrophage chemoattractant protein-1, in adipose tissues. Treatment of obese mice with GLN downregulated hepatic proteomic profiles associated with the gluconeogenesis pathway and improved glucose tolerance. Moreover, macrophage infiltration and adipose tissue inflammation were attenuated after the sleeve gastrectomy. These findings imply that postoperative intravenous GLN administration may improve glucose tolerance and attenuate inflammation shortly after the bariatric surgery in subjects with obesity.

Comparison of postoperative liver function between different dissection techniques during laparoscopic cholecystectomy

Aim:

In this study, we investigated and compared the effect of different types of dissector (Maryland vs Hook) on changes in liver function tests (LFTs) after laparoscopic cholecystectomy.

Patients & methods:

The enrolled patients were divided into two groups. Group A patients underwent dissection by Maryland dissecting forceps, group B by Hook dissecting instrument. LFTs were measured preoperatively and at 1 day and 1 week, postoperatively.

Results:

For both Maryland and Hook dissection, the 1-day postoperative values for total bilirubin, alanine aminotransferase and aspartate aminotransferase were significantly higher than the preoperative values. Also, there were no statistical differences between Hook and Maryland.

Conclusion:

The elevation of LFTs seems to be attributed to other factors.

Laparoscopic cholecystectomy (LC) is an alternative to laparotomy and has become the standard treatment of benign gallbladder diseases. However, it has been noted that (following LC) the serum level of certain liver function tests (LFT) raises markedly in patients who had preoperatively normal LFT. Pneumoperitoneum is the main contributing factor. This is the first study to evaluate the effect of different dissectors on alteration of LFTs after LC. As there were no statistical differences in the variation of LFTs between the Maryland and Hook, it seems that the dissector type has no effect on the alteration of LFTs.

A novel liver retraction method in laparoscopic gastrectomy for gastric cancer

BACKGROUND

Retracting the lateral liver segment during laparoscopic distal gastrectomy is important for achieving an optimal surgical field. However, excessive force may injure the liver, causing temporary abnormalities of liver function tests after laparoscopic surgery. We developed a new liver retraction method and assessed its safety and utility.

PATIENTS AND METHODS

We retrospectively analyzed records in our surgical database of consecutive surgical patients who underwent laparoscopic distal gastrectomy for early gastric cancer. We divided the 229 patients into two groups based on the liver retraction method used, either flexible liver retraction with clipping and suturing (FLICS) or the Nathanson retractor (NR). One-to-one propensity score matching was performed to match patients, resulting in the records of 53 pairs of cases extracted from the database. Operative and postoperative outcomes were assessed, including following the values of serum liver enzymes, total bilirubin, and C-reactive protein until postoperative day 30.

RESULTS

There were no significant differences in patient characteristics or preoperative data in the two groups. The retraction method was not changed intraoperatively for any patients. The operative time was significantly shorter in the FLICS group, but the amount of bleeding did not differ. Liver injury was not observed as a result of liver retraction during surgery. In both groups, serum liver enzymes temporarily increased after surgery but improved rapidly thereafter. The postoperative increases in aspartate transaminase, alanine transaminase, and C-reactive protein levels were significantly lower in the FLICS than in the NR group. No serious complications associated with liver retraction were observed in either group.

CONCLUSIONS

Our new liver retraction technique provided an optimal surgical field without inducing liver dysfunction. It is a simple, safe, and effective liver retraction technique.

Atraumatic Liver Retraction Using Nelaton Catheters During Totally Laparoscopic Gastrectomy

This study introduces a novel technique for liver retraction during laparoscopic gastrectomy and assesses its impact on postoperative recovery. This study included 139 patients in whom Nelaton catheters (n=57) or Nathanson retractors (n=82) were used for liver retraction. Serum liver enzyme levels were measured preoperatively and on the first, second, third, fifth, and seventh postoperative days. Clinicopathologic features and postoperative recovery variables between the 2 groups were compared. The aspartate aminotransferase, alanine aminotransferase, and C-reactive protein levels were significantly lower (P<0.001, P<0.001, and P=0.007, respectively), and the day of first flatus, the day of initiating a soft diet, and the length of hospital stay were shorter in the Nelaton catheter U-shaped retractor group than those seen in the Nathanson retractor group (P=0.035, P=0.002, and P=0.024, respectively). Atraumatic liver retraction with Nelaton catheters is recommended in laparoscopic gastrectomy.

Monitoring of Liver Function Tests after Roux-en-Y Gastric Bypass: An Examination of Evidence Base

There is no consensus on the monitoring of liver function tests after Roux-en-Y gastric bypass (RYGB). Since the main objective of such monitoring would be to diagnose early those who will eventually develop liver failure after RYGB, we performed a systematic review on this topic. An extensive search of literature revealed only 10 such cases in 6 published articles. It would hence appear that liver failure is a rare problem after RYGB. Routine lifelong monitoring of liver function tests is therefore unnecessary for otherwise asymptomatic individuals. Such monitoring should hence be reserved for high-risk groups, such as patients with liver cirrhosis, those undergoing extended limb/distal RYGB, patients with new illnesses, those abusing alcohol, those on hepatotoxic drugs and those presenting with a surgical complication.

Application of Laparoscopic Gastrectomy in Obese Patients (BMI≥30 kg/m2) with Gastric Cancer: A Comparison With Open Gastrectomy Regarding Short-term Outcomes

OBJECTIVE

Few studies have compared the surgical outcomes of laparoscopic (LG) and open (OG) gastrectomy in obese patients (BMI≥30 kg/m) with gastric cancer. The current study aimed to investigate the short-term outcomes of LG in this group of patients.

METHODS

A total of 33 LG cases and 23 OG cases (BMI≥30 kg/m) were identified from our gastric cancer database. Clinicopathologic features, operative details, laboratory examination, and postoperative outcomes were compared between both groups. Regression analysis was used to determine the effects of BMI on intraoperative outcomes.

RESULTS

The 2 groups had comparable clinicopathologic characteristics. LG was associated with significantly lesser blood loss, whereas both also groups had a similar operative time, and number of harvested lymph nodes. However, regression analysis indicated that increased BMI affected the operative time and blood loss in patients that underwent OG but had little effect on patients who received LG. The elevation of inflammatory factors (WBC, CRP) was lower in LG than in OG, postoperatively. Postoperative hepatic (alanine aminotransferase, total bilirubin, albumin) and renal (creatinine, blood urea nitrogen) functions in the LG group were not worse than in the OG group. The time to first flatus, initiation of diet, hospitalization, and postoperative complications seemed superior in LG than in OG, but these differences were not statistically significant.

CONCLUSION

LG can be safely performed in obese gastric cancer patients. Compared with conventional OG, LG is less invasive and is characterized by less blood loss and milder surgical trauma. LG is also less adversely affected by increased BMI.

Short- and long-term mortality after bariatric surgery: A systematic review and meta-analysis

AIMS

The objective of this study was to investigate short- (≤ 30 days) and long-term (≥ 2 years) all-cause mortality after bariatric surgery among adult patients with obesity.

MATERIALS AND METHODS

For short-term mortality, eligible studies comprised randomized controlled trials (RCTs) reporting perioperative mortality. For long-term mortality, eligible studies comprised RCTs and observational studies comparing mortality between obese patients after bariatric surgery and non-operated controls. Random-effects models using a Bayesian or frequentist approach were used to pool effect estimates of short- and long-term mortality, respectively.

RESULTS

Short-term all-cause mortality based on 38 RCTs involving 4030 patients was 0.18% (95% CI, 0.04%-0.38%) and was higher for open surgeries (0.31%; 95% CI, 0.03%-0.97%) and similar in mixed surgeries (0.17%; 95% CI, 0.03%-0.43%) and restrictive surgeries (0.17%; 95% CI, 0.03%-0.45%). For long-term mortality, 12 observational studies involving 27 258 operated patients and 97 154 non-operated obese controls were included. Of these, 8 studies were eligible for the meta-analysis, which showed a reduction of 41% in all-cause mortality (hazard ratio, 0.59; 95% CI, 0.52-0.67; P < .001). Additionally, operated patients were 0.42 times as likely (95% CI, 0.25-0.72, P < .001) and 0.47 times as likely (95% CI, 0.36-0.63, P < .001) as non-operated obese controls to die from cardiovascular diseases and cancer, respectively.

CONCLUSIONS

Bariatric surgery is associated with low short-term mortality and may be associated with long-term reductions in all-cause, cardiovascular and cancer-related mortality.

Exogenous phosphatidylcholine supplementation retrieve aluminum-induced toxicity in male albino rats

This study investigated the ameliorative potential of exogenous phosphatidylcholine (PC) against aluminum-induced toxicity in male albino rats. Four groups of rats were used for this study (N = 8): group I served as the control, group II (PC treated) received L-α-phosphatidylcholine (egg yolk-derived) 100 mg/kg bwt/day orally, group III (aluminum treated) received aluminum chloride 100 mg/kg bwt/day orally, and group VI (aluminum + PC treated) received similar oral dose of aluminum and PC (100 mg/kg bwt/day). Treatment was continued for 8 weeks. Results revealed that aluminum chloride treatment leading to a significant elevation in serum aspartate aminotransferase, serum alanine aminotransferase, urea, creatinine, malondialdehyde, serum cytokines (tumor necrosis factor-α, interleukin-6), and brain content of acetylcholine, as well as a significant reduction in serum-reduced glutathione, serum testosterone, and brain content of acetylcholinesterase. Moreover, aluminum administration caused significant histopathological alteration in liver, kidney, brain, testes, and epididymis. Co-treatment with exogenous PC resulted in significant improvement in intensity of histopathologic lesions, serum parameters, testosterone level, proinflammatory cytokines, and oxidative/antioxidative status. However, it does not affect the brain content of acetylcholine and acetylcholinesterase. Conclusively, treatment with exogenous PC can retrieve the adverse effect of aluminum toxicities through its antioxidative and anti-inflammatory properties.

The influence of Omega3 fatty acids supplementation against aluminum-induced toxicity in male albino rats

This study evaluated the protective and antioxidant potential of Omega3 fatty acids (FAs) against aluminum intoxicated male albino rats. Twenty-four male albino rats were divided into four equal groups: group I served as control; group II (Omega3-treated) received Omega3 FAs 1000 mg/kg bwt/day orally; group III (aluminum-treated) received aluminum chloride 100 mg/kg bwt/day orally and group IV (aluminum + Omega3-treated) received aluminum chloride 100 mg/kg bwt/day and Omega3 FAs 1000 mg/kg bwt/day orally. Treatments lasted for 4 weeks. Results indicate that administration of aluminum chloride showed non-significant changes in serum alanine aminotransferase, urea, and creatinine levels, a significant increase in serum aspartate aminotransferase and malondialdehyde as well as a significant reduction in serum-reduced glutathione levels. Aluminum treatment induced histopathological alterations in the liver, kidney, brain, testes, and epididymis. Omega3 FAs supplementation improved the serum parameters, enhanced endogenous antioxidant status, reduced lipid peroxidation, and ameliorated the intensity of the histopathological lesions. These findings reveal that Omega3 FAs supplementation can lighten the toxic effects of aluminum through their antioxidant and free radical-scavenging effects.

The Effect of Intraoperative N-Acetylcysteine on Hepatocellular Injury During Laparoscopic Bariatric Surgery. A Randomised Controlled Trial

BACKGROUND

The combination of pneumoperitoneum and intraoperative retraction of the left lobe of the liver leads to hepatocellular injury during laparoscopic gastric surgery. Fatty livers are more susceptible to ischaemic insults. This trial investigated whether the antioxidant N-acetylcysteine (NAC) reduced liver injury during laparoscopic sleeve gastrectomy (LSG).

METHODS

Patients undergoing LSG were randomised (single blinded) to receive intraoperative NAC infusion or standard anaesthetic treatment. Blood samples were taken before and after surgery (days 0 to 4). Primary endpoints included serum aminotransferases. Secondary measures were C-reactive protein, weight cell count (WCC), cytokines (interleukin 6 and 10) and cytokeratin-18 as markers of apoptosis. Intraoperative liver biopsy samples were assessed using a locally developed injury score.

RESULTS

Twenty patients (14 females, mean age 44.5 (SEM ± 2.9) years, mean BMI 60.8 (SEM ± 2.4) kg/m(2)) were recruited (NAC n = 10, control n = 10). The trial was stopped early after a planned interim analysis. Baseline liver function was similar. The peak rise in liver enzymes was on day 1, but levels were not significantly different between the groups. Rates of complications and length of stay were not significantly different. Secondary outcome measures, including white cell count (WCC), cytokines and cytokeratin (CK)-18 fragments, were not different between groups. Liver injury scores did not differ significantly.

CONCLUSIONS

NAC did not reduce intraoperative liver injury in this small number of patients. The heterogenous nature of the study population, with differences in co-morbidities, body mass index and intraabdominal anatomy, leads to a varied post-operative inflammatory response. Significant hepatocyte injury occurs through both necrosis and apoptosis.

What is the evidence for the use of low-pressure pneumoperitoneum? A systematic review

Background

Laparoscopic surgery has several advantages when compared to open surgery, including faster postoperative recovery and lower pain scores. However, for laparoscopy, a pneumoperitoneum is required to create workspace between the abdominal wall and intraabdominal organs. Increased intraabdominal pressure may also have negative implications on cardiovascular, pulmonary, and intraabdominal organ functionings. To overcome these negative consequences, several trials have been performed comparing low- versus standard-pressure pneumoperitoneum.

Methods

A systematic review of all randomized controlled clinical trials and observational studies comparing low- versus standard-pressure pneumoperitoneum.

Results and conclusions

Quality assessment showed that the overall quality of evidence was moderate to low. Postoperative pain scores were reduced by the use of low-pressure pneumoperitoneum. With appropriate perioperative measures, the use of low-pressure pneumoperitoneum does not seem to have clinical advantages as compared to standard pressure on cardiac and pulmonary function. Although there are indications that low-pressure pneumoperitoneum is associated with less liver and kidney injury when compared to standard-pressure pneumoperitoneum, this does not seem to have clinical implications for healthy individuals. The influence of low-pressure pneumoperitoneum on adhesion formation, anastomosis healing, tumor metastasis, intraocular and intracerebral pressure, and thromboembolic complications remains uncertain, as no human clinical trials have been performed. The influence of pressure on surgical conditions and safety has not been established to date. In conclusion, the most important benefit of low-pressure pneumoperitoneum is lower postoperative pain scores, supported by a moderate quality of evidence. However, the quality of surgical conditions and safety of the use of low-pressure pneumoperitoneum need to be established, as are the values and preferences of physicians and patients regarding the potential benefits and risks. Therefore, the recommendation to use low-pressure pneumoperitoneum during laparoscopy is weak, and more studies are required.

Recent advances in bariatric/metabolic surgery: appraisal of clinical evidence

Obesity and associated type 2 diabetes mellitus (T2DM) are becoming a serious medical issue worldwide. Bariatric surgery has been shown to be the most effective and durable therapy for the treatment of morbid obese patients. Increasing data indicates bariatric surgery as metabolic surgery is an effective and novel therapy for not well controlled obese T2DM patients. The review of recent developments in bariatric/metabolic surgery covers 4 major fields. 1) Improvement of safety: recent advances in laparoscopic/metabolic surgery has made this minimal invasive surgery more than ten times safer than a decade ago. The safety profile of laparoscopic/metabolic surgery is compatible with that of laparoscopic cholecystectomy now. 2) New bariatric/metabolic surgery: laparoscopic sleeve gastrectomy (LSG) is becoming the leading bariatric surgery because of its simplicity and efficacy. Other new procedures, such as gastric plication, banded plication, single anastomosis (mini) gastric bypass and Duodeno-jejunal bypass with sleeve gastrectomy have all been accepted as treatment modalities for bariatric/metabolic surgery. 3) Mechanism of bariatric/metabolic surgery: Restriction is the most important mechanism for bariatric surgery. Weight regain after bariatric surgery is usually associated with loss of restriction. Recent studies demonstrated that gut hormone, microbiota and bile acid changes after bariatric surgery may play an important role in durable weight loss as well as in T2DM remission. However, weight loss is still the cornerstone of T2DM remission after metabolic surgery. 4) PATIENT SELECTION: patients who may benefit most from bariatric surgery was found to be patients with insulin resistance. For Asian T2DM patients, the indication of metabolic surgery has been set to those with not well controlled (HbA1c > 7.5%) disease and with their BMI > 27.5 Kg/m(2). A novel diabetes surgical score, ABCD score, is a simple system for predicting the success of surgical therapy for T2DM.

Does pneumoperitoneum adversely affect growth, development and liver function in biliary atresia patients after laparoscopic portoenterostomy?

PURPOSE

We assessed the effect of high partial pressure of arterial carbon dioxide (PaCO2) due to pneumoperitoneum (PP) on growth (height/weight) and development (gross/fine motor function, receptive/expressive communication, and social interaction), by comparing outcome after portoenterostomy (PE) for biliary atresia (BA) using laparoscopic PE (LPE: n = 13) and open PE (OPE: n = 13) cases performed between 2005 and 2014.

METHODS

Our PE is based on Kasai's original PE. All data were collated prospectively.

RESULTS

Differences in duration of follow-up (LPE: 38.8 months; OPE: 38.1 months), jaundice clearance (LPE: 12/13 = 92.3 %; OPE: 9/13 = 69.2 %), survival with the native liver (LPE: 10/13 = 76.9 %; OPE: 9/13 = 69.2 %), incidence of cholangitis, hypersplenism, and incidence of esophageal varices were not significant. Mean intraoperative PaCO2 was significantly higher in LPE (LPE: 50.1 mmHg; OPE: 40.7 mmHg, p < 0.05). Liver function impairment was not statistically different, although LPE results were slightly worse. There was no overall delay in growth observed, although height/weight gain was more consistent in LPE. The pattern of developmental delay observed was similar for LPE and OPE suggesting that developmental delay is not PE-related; in other words, PP is not implicated in developmental delay.

CONCLUSIONS

PP during LPE would appear to have no adverse effects on overall growth/development and liver function in BA patients.

Potential protective effects of extra virgin olive oil on the hepatotoxicity induced by co-exposure of adult rats to acrylamide and aluminum

Extra virgin olive oil has been shown to be effective against oxidative stress associated diseases.

Association between duration of carbon dioxide pneumoperitoneum during laparoscopic abdominal surgery and hepatic injury: a meta-analysis

BACKGROUND

The aim of this study is to accurately assess whether the duration of intraoperative carbon dioxide pneumoperitoneum (CDP) is associated with the induction of hepatic injury.

METHODS

We conducted a systematic review of PubMed, Embase, and Cochrane Library databases (through February 2014) to identify case-match studies that compared high-pressure CDP with low-pressure CDP or varied the duration of CDP in patients who underwent abdominal surgery. The outcome of interest was postoperative liver function (ALT, AST, TB).

RESULTS

Eleven comparative studies involving 2,235 participants were included. Overall, levels of ALT, AST, and TB (on postoperative days 1, 3, and 7) were significantly elevated in the study groups. However, the results of the subanalyses of those who underwent laparoscopic colorectal cancer resection (LCR) versus open colorectal cancer resection (OCR) and those who underwent laparoscopic gastric bypass (LGBP) versus open gastric bypass (OGBP) were inconsistent.

CONCLUSIONS

The current evidence suggests that the duration of CDP during laparoscopic abdominal surgery may be associated with hepatic injury. Additional large-scale, randomized, controlled trials are urgently needed to further confirm this.

Clinical significance of elevated intraabdominal pressure during common conditions and procedures

INTRODUCTION

Pregnancy, obesity, peritoneal dialysis, pneumoperitoneum, prone position and application of positive end-expiratory pressure are associated with elevated intraabdominal pressure (IAP).

OBJECTIVE

To review the relation between these conditions and procedures, and intraabdominal hypertension (IAH) or abdominal compartment syndrome (ACS).

METHODS

Search of PubMed and Google Scholar and review of article bibliographies.

RESULTS AND CONCLUSION

Only obesity, peritoneal dialysis, and pneumoperitoneum are associated with symptoms related to IAH and these symptoms are reversible.

Obesity Disease and Surgery

Obesity is a medical disease that is increasing significantly nowadays. Worldwide obesity prevalence doubled since 1980. Obese patients are at great risk for complications with physical and psychological burdens, thus affecting their quality of life. Obesity is well known to have higher risk for cardiovascular diseases, diabetes mellitus, musculoskeletal diseases and shorter life expectancy. In addition, obesity has a great impact on surgical diseases, and elective surgeries in comparison to general population. There is higher risk for wound infection, longer operative time, poorer outcome, and others. The higher the BMI (body mass index), the higher the risk for these complications. This literature review illustrates the prevalence of obesity as a diseases and complications of obesity in general as well as, in a surgical point of view, general surgery perioperative risks and complications among obese patients. It will review the evidence-based updates in these headlines.

Recent advances in laparoscopic surgery

Laparoscopic surgery has been widely adopted and new technical innovation, procedures and evidence based knowledge are persistently emerging. This review documents recent major advancements in laparoscopic surgery. A PubMed search was made in order to identify recent advances in this field. We reviewed the recent data on randomized trials in this field as well as papers of systematic review. Laparoscopic cholecystectomy is the most frequently performed procedure, followed by laparoscopic bariatric surgery. Although bile duct injuries are relatively uncommon (0.15%-0.6%), intraoperative cholangiography still plays a role in reducing the cost of litigation. Laparoscopic bariatric surgery is the most commonly performed laparoscopic gastrointestinal surgery in the USA, and laparoscopic Nissen fundoplication is the treatment of choice for intractable gastroesophageal reflux disease. Recent randomized trials have demonstrated that laparoscopic gastric and colorectal cancer resection are safe and oncologically correct procedures. Laparoscopic surgery has also been widely developed in hepatic, pancreatic, gynecological and urological surgery. Recently, SILS and robotic surgery have penetrated all specialties of abdominal surgery. However, evidence-based medicine has failed to show major advantages in SILS, and the disadvantage of robotic surgery is the high costs related to purchase and maintenance of technology. Laparoscopic surgery has become well developed in recent decades and is the choice of treatment in abdominal surgery. Recently developed SILS techniques and robotic surgery are promising but their benefits remain to be determined.

The genotoxic, hepatotoxic, nephrotoxic, haematotoxic and histopathological effects in rats after aluminium chronic intoxication

Aluminium (Al) is used in water purification and is also present in several manufactured foods and medicines. Al is known to induce a broad range of physiological, biochemical and behavioural dysfunctions in laboratory animals and humans. This investigation was carried out to investigate the effects of subchronic exposure to Al (as AlCl3) in rats. Sprague-Dawley rats were randomly separated into two groups. Group 1 rats treated with sodium chloride served as the control, group 2 rats were treated with Al (as AlCl3, 5 mg/kg body weight) intraperitonally for 10 weeks. Animals were killed and blood samples were analyzed for blood serum alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) enzyme activities and creatinine, urea (U) and uric acid (UA) levels for evaluating hepatotoxicity and nephrotoxicity. Blood parameters including red blood cells (RBCs), haemoglobin (Hb) concentration, haematocrit (Ht), platelets (PLTs) and white blood cells (WBCs) were compared between control and experimental group to assess haematoxicity. In order to determine the genotoxicity, the number of micronucleated hepatocytes (MNHEPs) was counted in isolated hepatocytes. In addition, histological alterations in liver and kidney samples were investigated. After exposure with Al, the enzymatic activities of ALP, AST, ALT and LDH, and the levels of U and UA significantly increased. RBC, WBC, PLT, Hb and Ht revealed significant decreases in experimental group compared to the control. AlCl3 caused a significant increase in MNHEPs. Furthermore, severe pathological damages were established in both liver and kidney samples. Subchronic exposure to low doses of Al can produce serious dysfunctions in rat blood, liver and kidney, and exposure to this metal can result in greater damages.

Biochemical Effects of Low-Flow Anesthesia with Inhalation agents in Patients undergoing Laparoscopic Surgery

This study was designed to investigate the effects of low-flow anesthesia with sevoflurane and desflurane on renal and hepatic functions in patients undergoing laparoscopic abdominal surgery. Twenty patients with ASA I or II (American Society of Anesthesiologists classification) physical scores were included in the study. There were no significant differences between sevoflurane and desflurane groups with respect to age, weight, body mass index, duration of the operation and the anesthesia. In both groups, renal function parameters such as urea, BUN, creatinine and calculated creatinine clearance did not show significant differences at 24 and 48 hours. Homocysteine levels, which showed renal metabolic function, did not change significantly at 24 and 48 hours when compared to baseline levels in both groups. Transaminases were not significantly different between the two groups from baseline to 24 and 48 hours. These differences between the preoperative and postoperative values of biochemical parameters were similar for both anesthetic groups (p>0.05). Low-flow anesthesia did not cause impairment in terms of renal and hepatic functions.

Routine testing of liver function before and after elective laparoscopic cholecystectomy: is it necessary?

This study suggests that mild to moderate elevation in preoperative liver function tests may not be associated with deleterious effects, and in the absence of clinical indications, routine preoperative or postoperative liver function testing may not be necessary.

Background and Objectives:

Liver function tests (LFTs) include alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), and bilirubin. The role of routine testing before and after laparoscopic cholecystectomy was evaluated in this study.

Patients and Methods:

A total of 355 patients were retrospectively analyzed by examining the LFTs the day before, the day after, and 3 weeks after the surgery. The Wilcoxon signed-rank test and Student t test were performed to determine statistical significance.

Results:

Alterations in the serum AST, ALT, and GGT were seen on the first postoperative day. Minor changes were seen in bilirubin and ALP. An overall disturbance in the LFTs was seen in more than two-thirds of the cases. Repeat LFTs performed after 3 weeks on follow-up were found to be within normal limits.

Conclusion:

Mild-to-moderate elevation in preoperative LFTs may not be associated with any deleterious effect, and, in the absence of clinical indications, routine preoperative or postoperative liver function testing is unnecessary.

Minimizing hepatic trauma with a novel liver retraction method: a simple liver suspension using gauze suture

BACKGROUND

Prolonged liver retraction during radical gastrectomy for adequate exposure of the hepatogastric ligament may lead to hepatic trauma. The authors offer a new minimally traumatic liver retraction method using a simple liver suspension with a gauze suture and compare it with the modified liver-puncture method.

METHODS

This study retrospectively evaluated 92 patients who underwent the liver-suspension or liver-puncture method during gastric resections in 2010. Their clinical and operative characteristics were analyzed together with perioperative transaminases, and the two groups were compared. Patients with a history of liver disease, abnormal preoperative liver function test results, postoperative complications, or combined operations were excluded from the study. The liver-suspension method was performed using two 4 × 4-in. gauze pads threaded with a 2-0 Prolene suture, which were secured to the pars condensa with surgical clips and externally tied to suspend the liver toward the abdominal wall.

RESULTS

Each liver retraction was completed without intraoperative complications. The patients in the liver-suspension group had more nonhepatic comorbidities than those in the liver-puncture group (P = 0.029). Other patient characteristics such as age, gender, and body mass index (BMI) did not differ between the two groups. No differences were found between the groups in terms of mean operative time (200.3 ± 66.9 vs 214.9 ± 74.4) or preoperative mean alanine aminotransferase (ALT) or aspartate aminotransferase (AST) levels. However, the patients in the liver-suspension group had significantly lower postoperative mean ALT levels (postoperative days 0, 1, 2, 3, and 5) and mean AST levels (postoperative days 0 and 1).

CONCLUSION

Compared with the liver-puncture method, the authors' novel liver-suspension with suture-gauze technique is a safe and effective method for retracting the liver during laparoscopic and robotic upper abdominal surgeries.

A protective technique for retraction of the liver during laparoscopic gastrectomy for gastric adenocarcinoma: using a Penrose drain

BACKGROUND

Retraction of the liver is necessary to ensure an adequate working space in laparoscopic surgery, but the retraction force applied may cause transient liver dysfunction. We have introduced the technique using a Penrose drain to suspend the liver with the performance of laparoscopic gastrectomy for gastric adenocarcinoma.

METHODS

111 patients with gastric adenocarcinoma underwent laparoscopic gastrectomy using either a Penrose drain (n = 47) or a Nathanson's retractor (n = 64) for displacement of the liver. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin, alkaline phosphatase (ALP) and albumin were compared among the groups at baseline, immediately after operation, and on postoperative days (POD) 1, 2, 3, 5, and 7.

RESULTS

The levels of ALT on POD 2, 3, and 5 were significant higher in the Nathanson's retractor group than in the Penrose drain group. Levels of AST on POD 2 and 3 were also higher in the Nathanson's retractor group than in the Penrose drain group. There was no significant difference in total bilirubin, ALP, and serum albumin levels between groups.

CONCLUSIONS

The use of the Penrose drain for retraction of the liver appears to attenuate postoperative liver dysfunction during laparoscopic gastrectomy for gastric adenocarcinoma.

Liver function alterations after laparoscopy-assisted gastrectomy for gastric cancer and its clinical significance

AIM: To evaluate the factors associated with liver function alterations after laparoscopy-assisted gastrectomy (LAG) for gastric cancer.

METHODS: We collected the data of gastrectomy patients with gastric cancer and divided them into 2 groups: open gastrectomy (OG) and LAG. We also collected the data of patients with colon cancer to evaluate the effect of liver manipulations during surgery on liver function alterations. Serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin, and alkaline phosphatase were measured on the preoperative day and postoperative day 1 (POD1), POD3, POD5, and POD7.

RESULTS: No changes in liver function were observed after the operation in patients with colon cancer (n = 121). However, in gastric cancer patients (n = 215), AST and ALT levels increased until POD5 compared to those in colon cancer patients and these findings were observed both in the LAG and OG without a significant difference except at POD1. The mean hepatic enzyme levels at POD1 in the LAG group were significantly higher than those in the OG group (P = 0.047 for AST and P = 0.039 for ALT). The factors associated with elevated ALT on POD1 in patients with gastric cancer were body mass index (P < 0.001), operation time (P < 0.001), intraoperative hepatic injury (P = 0.048), and ligation of an aberrant left hepatic artery (P = 0.052) but not type of operation (OG vs LAG, P = 0.094).

CONCLUSION: We conclude that the liver function alteration after LAG may have been caused by direct liver manipulation or aberrant hepatic artery ligation rather than the CO₂ pneumoperitoneum.

Increased susceptibility to liver damage from pneumoperitoneum in a murine model of biliary atresia

HYPOTHESIS

We hypothesized that livers with biliary atresia (BA) are more susceptible to the harmful effects of a high-pressure CO(2) pneumoperitoneum (PP) than healthy livers.

METHODS

A murine model of BA was used in this experiment. Mice were divided into 6 groups: (1) control Balb/c; (2) control Balb/c, CO(2)-PP; (3) control BA; (4) BA-sham; (5) BA, CO(2)-PP; and (6) BA, air-PP. Mice from groups 2, 5, and 6 underwent an 8-mm Hg-PP for 60 minutes. Liver samples were collected for histology, colorimetry, and flow cytometry analysis 18 to 24 hours after the procedure. Markers of apoptosis were investigated as indicators of acute cell damage.

RESULTS

We observed a statistically significant higher rate of apoptosis in livers with BA exposed to a prolonged CO(2)-PP or air-PP compared with control groups. There were no significant differences between groups 1 and 2, or between groups 5 and 6.

CONCLUSIONS

In this animal model, we have shown that livers with BA are more susceptible than healthy livers to injury by a prolonged PP. This injury was caused by both CO(2) and air-PP, implying that it is the direct result of pressure. These results may have implications for the success of minimally invasive Kasai procedures.

Propolis prevents aluminium-induced genetic and hepatic damages in rat liver

Aluminium is present in several manufactured foods and medicines and is also used in water purification. Therefore, the present experiment was undertaken to determine the effectiveness of propolis in modulating the aluminium chloride (AlCl(3)) induced genotoxicity and hepatotoxicity in liver of rats. Animals were assigned to 1 of 4 groups: control; 34 mg AlCl(3)/kg bw; 50mg propolis/kg bw; AlCl(3) (34 mg/kg bw) plus propolis (50mg/kg bw), respectively. Rats were orally administered their respective doses daily for 30 days. At the end of the experiment, rats were anesthetized and hepatocytes (HEP) were isolated for counting the number of micronucleated hepatocytes (MNHEPs). In addition, the levels of serum enzymes and histological alterations in liver were investigated. AlCl(3) caused a significant increase in MNHEPs, alkaline phosphatase, transaminases (AST and ALT) and lactate dehydrogenase (LDH). Furthermore, severe pathological damages such as: sinusoidal dilatation, congestion of central vein, lipid accumulation and lymphocyte infiltration were established in liver. On the contrary, treatment with propolis alone did not cause any adverse effect on above parameters. Moreover, simultaneous treatments with propolis significantly modulated the toxic effects of AlCl(3). It can be concluded that propolis has beneficial influences and could be able to antagonize AlCl(3) toxicity.

Procedure and outcomes of Roux-en-Y gastric bypass

Bariatric surgery is an effective intervention for weight loss in the morbidly obese patient and can result in resolution of associated comorbidities. However, it is a complex area of practice and care, as these patients suffer a series of comorbidities that can compromise outcomes after surgery. Nurses must be aware of these comorbidities and anticipate the required interventions to ensure timely and effective treatment, and to minimize potential problems. This article reviews the technical procedures of the laparoscopic Roux-en-Y gastric bypass (LRYGBP)--which is considered the gold standard in bariatric surgery--and outlines its complications and outcomes. Other forms of bariatric surgery are briefly discussed in comparison to the LRYGBP. With knowledge in this area, nurses are in a ideal position to educate and prepare patients for life after surgery, and to diminish their anxiety during adaptation to this new phase of life.

Biodistribution of technetium-99m pertechnetate after Roux-en-Y gastric bypass (Capella technique) in rats

PURPOSE: The biodistribution of sodium pertechnetate, the most used radiopharmaceutical in nuclear medicine, has not been studied in details after bariatric surgery. The objective was to investigate the effect of Roux-en-Y gastric bypass (RYGB) on biodistribution of sodium pertechnetate (Na99mTc-) in organs and tissues of rats. METHODS: Twelve rats were randomly divided into two groups of 6 animals each. The RYGB group rats were submitted to the Roux-en-Y gastric bypass and the control group rats were not operated. After 15 days, all rats were injected with 0.1mL of Na99mTc- via orbital plexus with average radioactivity of 0.66 MBq. After 30 minutes, liver, stomach, thyroid, heart, lung, kidney and femur samples were harvested, weighed and percentage of radioactivity per gram (%ATI/g) of each organ was determined by gama counter Wizard Perkin-Elmer. We applied the Student t test for statistical analysis, considering p<0.05 as significant. RESULTS: Significant reduction in mean %ATI/g was observed in the liver, stomach and femur in the RYGB group animals, compared with the control group rats (p<0.05). In other organs no significant difference in %ATI/g was observed between the two groups. CONCLUSION: This work contributes to the knowledge that the bariatric surgery RYGB modifies the pattern of biodistribution of Na99mTc-.

Can a short course of prophylactic low-dose proton pump inhibitor therapy prevent stomal ulceration after laparoscopic Roux-en-Y gastric bypass?

BACKGROUND

The purpose of this retrospective analysis was to determine if a short course of prophylactic proton pump inhibitor (PPI) therapy can prevent stomal ulceration after laparoscopic Roux-en-Y gastric bypass (LRYGBP).

METHODS

Four hundred forty-nine consecutive patients who underwent LRYGBP and had a minimum of 6 months follow-up were included. Patients were categorized in two groups: patients with Helicobacter pylori at preoperative endoscopy (HP group) and patients without H. pylori (non-HP group). All patients in the HP group were medically treated prior to surgery. In both groups, almost half of the patients received low-dose proton pump inhibitors (omeprazole 20 mg daily) for 1 month following LRYGBP.

RESULTS

The incidence of stomal ulceration in the HP group was not statistically different from the incidence in the non-HP group (7/86, 8.14% vs. 41/363, 11.29%; p = 0.559). When comparing the patients who did receive PPI therapy with the patients who did not receive PPI therapy within the non-HP group, there was no significant reduction in development of stomal ulceration (18/169, 10.65% vs. 23/194, 11.86%; p = 0.743). When comparing the patients who did receive PPI therapy with the patients who did not receive PPI therapy within the HP group, there is a significant reduction in development of stomal ulceration (0/41, 0% vs. 7/45, 15.56%; p = 0.0123).

CONCLUSION

Development of stomal ulceration in patients tested positive for H. pylori prior to LRYGBP can be prevented by prophylactic low-dose PPI therapy following surgery.

Laparoscopic versus open splenectomy in dogs

In the last few years, the use of laparoscopy in veterinary medicine has expanded and consequently so was the need for studies that establish the advantages, disadvantages and possible complications of each procedure. The purpose of the current study was to describe a laparoscopic splenectomy technique and the alterations due to this access, and compare it to the open procedure in dogs. A total of 15 healthy female mongrel dogs were used, with mean weight of 17.4±2.5kg. The animals were distributed into three groups: Group IA of open splenectomy (laparotomy) using double ligation of the vessels of the splenic hilum with poliglicolic acid, Group IB of open splenectomy (laparotomy) with bipolar electrocoagulation of the splenic hilum, and Group II of laparoscopic access with bipolar electrocoagulation of the splenic hilum. Operative time, blood loss, size of incisions, complications during and after surgery were evaluated. Other parameters included pain scores, white blood cell (WBC) counts and postoperative serum concentrations of alanine aminotransferase (ALT), alkaline phosphatase (ALP), creatine kinase (CK), C-reactive protein (CRP), glucose and cortisol. No differences were found in the evaluation of parameters between both open splenectomy techniques employed. Laparoscopic access presented significant differences (p<0,05) when compared with open surgery: Longer operative time, smaller abdominal access, decrease in blood loss, lower concentrations of CRP, higher levels of CK and ALP, and lower scores in the pain scale. Laparoscopic surgery showed fewer complications of the surgical wound. No significant differences were observed between groups in the postoperative temperature, WBC, ALT, cortisol and glucose concentrations. In conclusion, the laparoscopic technique is useful for splenectomy in dogs, being advantageous in terms of blood loss, surgical stress and surgical wounds. However, it expends more operative time and causes transitory increase in hepatic and muscular enzymes.

Retraction transaminitis: an inevitable but benign complication of laparoscopic fundoplication

BACKGROUND

Transient transaminitis has been identified following laparoscopic abdominal surgery. However, the importance of posture, duration of surgery, and mechanical retraction in its etiology remain unclear.

METHODS

Liver function was assessed preoperatively then at 8, 24, 48 and 72 h following laparoscopic surgery including the following procedures: Nissen fundoplication (LN: n = 10); cholecystectomy (LC: n = 10); inguinal herniorrhaphy (LH: n = 10); and gastrectomy (LG: n = 5).

RESULTS

Aspartate aminotransferase (AST) levels in LN patients exhibited a rapid rise within 8 h, peaking at 48 h before returning toward baseline. In the LN group, AST levels were significantly higher at 8 h and 24 hours compared to all other groups and compared to LG at 48 h and 72 h. At 6-week follow-up all AST levels were normal. No significant differences were seen in other hepatic parameters, and no correlation between AST and duration of operation, gender, or age was identified.

CONCLUSIONS

Antireflux surgery is associated with transaminitis related to hepatic retraction, which is independent of patient posture or duration of observation, and it resolves spontaneously with no clinical consequences.

The impact of bariatric surgery on nonalcoholic fatty liver disease

PURPOSE OF REVIEW

To analyze the effects of bariatric surgery on nonalcoholic fatty liver disease by reviewing the most important and recent studies.

RECENT FINDINGS

The prevalence of obesity has increased dramatically over the last decades. Comorbidities related to obesity, such as nonalcoholic fatty liver disease are also increasing. Nonalcoholic fatty liver disease is a progressive disease with potential evolution to liver cirrhosis and hepatocellular carcinoma. Overweight patients who have nonalcoholic fatty liver disease should be considered for a weight loss program; however, long-term result with dietary interventions and drug therapy has been disappointing. Bariatric surgery is effective in promoting long-term weight loss in morbidly obese patients with control of comorbidities, especially those associated with the metabolic syndrome. On the basis of the early experience with extensive intestinal bypass, it was believed that rapid weight loss could cause liver damage. In contrast, recent prospective and retrospective observational studies and case series have demonstrated that bariatric surgery is well tolerated and is associated with nonalcoholic fatty liver disease regression in a significant number of patients.

SUMMARY

There is good level of evidence that bariatric surgery is associated with nonalcoholic fatty liver disease regression in morbidly obese patients.

Are African-Americans as successful as Caucasians after laparoscopic gastric bypass?

BACKGROUND

Laparoscopic Roux-en-Y gastric bypass (LRYGBP) has been demonstrated to provide weight loss comparable to open gastric bypass. It has been suggested that African-Americans (AA) are not as successful as Caucasians (CA) after bariatric surgery. Our hypothesis was that AAs are just as successful as CA after LRYGBP in terms of weight loss and comorbidity improvement.

METHODS

A retrospective chart review was performed on all AA and CA patients who underwent LRYGBP for a 6-month period. Success after LRYGBP [defined as (1) 25% loss of preoperative weight, (2) 50% excess weight loss (EWL), or (3) weight loss to within 50% ideal weight] was compared by ethnicity.

RESULTS

102 patients were included in this study. 97 patients (30 AA patients and 67 CA patients) had at least 1-year follow-up data available. Preoperative data did not differ between both groups. There was a statistically significant difference in %EWL between AA and CA (66% vs 74%; P<0.05). However, there was no ethnic difference in the percentage of patients with successful weight loss (as defined by any of the above 3 criteria). Furthermore, there was no statistical difference between the percentages of AA and CA patients who had improved or resolved diabetes and hypertension.

CONCLUSIONS

LRYGBP offers good weight loss in all patients. While there may be greater %EWL in CA patients, no ethnic difference in successful weight loss exists. More importantly, co-morbidities improve or resolve equally between AA and CA patients. LRYGBP should be considered successful in AA patients.

Laparoscopic bariatric patients’ will to help: the foundation of research

BACKGROUND

Bariatric surgery is a fast growing field. Clinical research is essential to its safe delivery. Bariatric patient enthusiasm for research participation has never been objectively measured. Our hypothesis was that most laparoscopic bariatric surgery patients would participate in clinical research.

METHODS

All postoperative patients were surveyed querying their willingness to participate in studies and quantifying the level of time, effort, and commitment they would comply with. Fisher's exact test, the Mann-Whitney U test, and the chi-square test were used to analyzed the responses. A total of 97 patients were the subject of this inquiry.

RESULTS

Of the 97 patients, 92% were willing to participate. Willingness was independent of race or diabetic status. Of those willing to participate, 93% agreed to additional blood tests done during routine blood draws and 75% agreed to additional blood draws. Although 98% agreed to donate fat samples during surgery, only 76% would donate at 1 month postoperatively. Also, 80% would spend 6 hours at 1 month postoperatively in the hospital for preoperative research. This decreased to 56% and 56% for 12 and 24 hours, respectively (P = .004). For postoperative research, 72% committed to 6 hours per month in the hospital. This decreased to 60% and 54% for 12 and 24 hours, respectively (P = .002). No statistical consensus was reached for the financial reimbursement patients desired for their time.

CONCLUSIONS

The results of our study have shown that almost all laparoscopic bariatric surgery patients are willing to participate in obesity-related research, including invasive procedures, when it coincides with their surgery. Enthusiasm decreased with the increasing time commitment in the pre- and postoperative period but remained for most patients.

What Happens to Patients who Do Not Follow-Up after Bariatric Surgery?

Loss of follow-up is a concern when tracking long-term clinical outcomes after bariatric surgery. The results of patients who are “lost to follow-up” are not known. After bariatric surgery, the lack of follow-up may result in less weight loss for patients. This study investigated the hypothesis that there are differences between patients who do not automatically return for their annual follow-up and those that do return. Patients who were greater than 14 months postoperative after laparoscopic gastric bypass were contacted if they had not returned for their annual appointment. They were seen in clinic and/or a phone interview was performed for follow-up. These patients (Group A) were compared with patients who returned to see us for their annual appointment (Group B) without us having to notify them. There were 105 consecutive patients, with 48 patients who did not automatically return for their annual appointment. Only six of these patients could not ultimately be contacted. There was no difference in preoperative body mass index between the two groups. Percentage excess body weight loss was greater in Group B (76 vs 65%; P < 0.003). More patients had successful weight loss (defined as within 50% of ideal body weight) in Group B (50 [88%] vs 28 [67%]; P < 0.02). We found that a significant number of patients will not comply with regular follow-up care after laparoscopic gastric bypass unless they are prompted to do so by their bariatric clinic. These patients have worse clinical outcome ( i.e., less weight loss). Caution should be taken when examining the results of any bariatric study where there is a significant loss to follow-up.

Unexpected pathology during laparoscopic bariatric surgery

BACKGROUND

The popularity of bariatric surgery has increased in recent years with the escalating incidence of morbid obesity in our society. The improvement in minimally invasive technology and the increased number of laparoscopic bariatric procedures being performed have resulted in the discovery of unexpected pathology not suspected preoperatively. The authors hypothesized that the occurrence of unexpected pathology is not associated with immediate adverse outcomes during laparoscopic bariatric procedures.

METHODS

From December 2002 to June 2004, 398 patients underwent laparoscopic bariatric surgery for morbid obesity. A retrospective chart review was performed to determine the incidence of unexpected findings and their effect on patient results.

RESULTS

Nine unexpected pathologic lesions were found in eight patients (2%). The findings included lesions on the small bowel (n = 3), stomach (n = 4), and liver (n = 2). In all cases except one (for which a biopsy was performed), the abnormalities were found and removed laparoscopically. The final pathology showed gastric leiomyomas (n = 2), gastric gastrointestinal stromal cell tumors (n = 2), ectopic pancreatic tissue (n = 2), arteriovenous malformation (n = 1), biliary adenoma (n = 1), and fibrosed hemangioma (n = 1). The planned bariatric procedures were completed for all the patients without incident. No complications occurred postoperatively, and all were discharged in 1 to 3 days (mean, 2 days).

CONCLUSIONS

Unexpected findings occur with relative frequency during laparoscopic bariatric procedures. Biopsy or removal of these lesions usually does not increase complications nor preclude continuation of the planned bariatric procedure.

Laparoscopic Repair of Gastrointestinal Leaks after Laparoscopic Gastric Bypass

Gastrointestinal (GI) leak after gastric bypass is a cause of significant morbidity and a mortality that may exceed 50%. This study was performed to review our experience with laparoscopic repair of GI leaks after laparoscopic Roux-en-Y gastric bypass (LRYGB). A retrospective chart review of all patients who underwent LRYGB over a 25-month period was performed. Patients who had any operation for a GI leak after LRYGB were included in this study. There were 300 patients who underwent LRYGB. No intraoperative conversions occurred. Eight (2.7%) patients underwent operative repair of a GI leak. Another patient had a gastrojejunostomy leak that was managed nonoperatively. The rate of GI leaks reduced from 5.3 per cent in the first 150 cases to 0.7 per cent in the last 150 cases (P < 0.05). One patient was converted to an open approach. Average operative time for the laparoscopic repairs was 133 minutes (range, 75–182 minutes). Sources of leak found at operation were gastrojejunostomy (3), enterotomy (3), jejunojejunostomy (2), gastric pouch (1), and cystic duct stump (1). Two patients had a GI leak from two sources. Average length of stay was 28 days (range, 4–78 days). Three patients whose stay was greater than a month were the result of sepsis and ventilator dependence. Further reoperations were required in two patients (laparoscopic) for abdominal washout and one patient (open) for enterotomy repair. One patient required computed tomography-guided drainage of an abscess. Mortality was 22 per cent (2) in patients who developed GI leaks. One patient died from sepsis-induced multiple organ failure and the other patient from a presumed pulmonary embolus. GI leaks cause significant morbidity and mortality. GI leak rates decrease with experience. Laparoscopic repair of GI leaks should be used judiciously. Conversions and further reoperations may be necessary.

Effect of increasing cardiac preload, sympathetic antagonism, or vasodilation on visceral blood flow during pneumoperitoneum

BACKGROUND AND AIMS

An impaired visceral perfusion caused by pneumoperitoneum may contribute to morbidity after laparoscopic surgery. The following three therapeutic concepts: increasing cardiac preload, controlled vasodilation, or selective sympathetic antagonism, were evaluated regarding a possible increase of visceral blood flow during pneumoperitoneum with carbon dioxide.

METHODS

Forty three pigs were assigned to treatment with an increase of preload and vasodilation (group A) or selective sympathetic antagonism with esmolol (group B). In both groups, pigs were assigned to head-up, head-down, or supine position. Perfusion of the vena porta and renal artery was measured by transonic volume flow meters and documented before capnoperitoneum, after induction of a 14-mmHg capnoperitoneum in each body position, after controlled vasodilation with sodium nitroprusside, and after controlled increase of intravascular volume by colloidal infusion.

RESULTS

Increasing intravascular volume improved portal blood flow in all body positions (p<0.05), but not renal blood flow. Medication of esmolol did not alter the measured parameters in any body position compared to control. Vasodilation with sodium nitroprusside reduced renal blood flow in supine and in head-up position.

CONCLUSION

An optimal intravascular volume was most effective in improving portal blood flow during capnoperitoneum in this trial. Esmolol had no negative effects on portal and renal blood flow. Patients with renal dysfunction might be treated carefully with sodium nitroprusside during capnoperitoneum.

Mini-laparotomy and full laparotomy, but not laparoscopy, alter hepatic macrophage populations in a rat model

BACKGROUND

Immune function is better preserved by laparoscopic versus conventional surgery. Numerous mediators of the systemic trauma response are synthesized and/or regulated by the liver. However, it has been stated that the advantages of laparoscopic surgery are no more obvious when conventional operations are performed via mini-laparotomy. We set out to compare the impact of laparoscopy and mini- and full laparotomy on the hepatic macrophage populations.

METHODS

Male Lewis rats were subjected to anesthesia alone (control), mini-laparotomy (1 cm), full laparotomy (7 cm), or laparoscopy for 60 min. Endpoints were the total protein in the peritoneal lavage fluid, hepatic ED-1 cells (recruited monocytes), hepatic ED-2 cells (Kupffer cells), the expression of OX-6 in the liver, and C-reactive protein (CRP) in plasma.

RESULTS

Protein in the peritoneal lavage fluid increased significantly after all interventions. Full laparotomy was accompanied by an enhancement in ED-1-positive monocytes in the liver parenchyma compared to all other groups (p < 0.001). Mini- and full laparotomy led to an increase in ED-2-positive Kupffer cells (p < 0.001). Laparoscopy did not affect the number of monocytes/macrophages. There was no significant alteration of OX-6 expression in either group. No change in the cellular composition in the periportal fields was observed. The CRP plasma levels did not significantly differ between groups.

CONCLUSIONS

Laparoscopy completely prevents hepatic macrophage populations from expansion and normal cell disposition is preserved. Laparotomy, irrespective of incision size, increases the number of Kupffer cells. Moreover, full laparotomy, but not mini-laparotomy or laparoscopy, causes an increase in hepatic monocyte recruitment. The regulating pathways after surgery differ from other immunologic challenges, such as sepsis, in which immunocompetent cells accumulate and are stimulated in the periportal fields.

The physiologic effects of pneumoperitoneum in the morbidly obese

OBJECTIVE

To review the physiologic effects of carbon dioxide (CO2) pneumoperitoneum in the morbidly obese.

SUMMARY BACKGROUND DATA

The number of laparoscopic bariatric operations performed in the United States has increased dramatically over the past several years. Laparoscopic bariatric surgery requires abdominal insufflation with CO2 and an increase in the intraabdominal pressure up to 15 mm Hg. Many studies have demonstrated the adverse consequences of pneumoperitoneum; however, few studies have examined the physiologic effects of pneumoperitoneum in the morbidly obese.

METHODS

A MEDLINE search from 1994 to 2003 was performed using the key words morbid obesity, laparoscopy, bariatric surgery, pneumoperitoneum, and gastric bypass. The authors reviewed papers evaluating the physiologic effects of pneumoperitoneum in morbidly obese subjects undergoing laparoscopy. The topics examined included alteration in acid-base balance, hemodynamics, femoral venous flow, and hepatic, renal, and cardiorespiratory function.

RESULTS

Physiologically, morbidly obese patients have a higher intraabdominal pressure at 2 to 3 times that of nonobese patients. The adverse consequences of pneumoperitoneum in morbidly obese patients are similar to those observed in nonobese patients. Laparoscopy in the obese can lead to systemic absorption of CO2 and increased requirements for CO2 elimination. The increased intraabdominal pressure enhances venous stasis, reduces intraoperative portal venous blood flow, decreases intraoperative urinary output, lowers respiratory compliance, increases airway pressure, and impairs cardiac function. Intraoperative management to minimize the adverse changes include appropriate ventilatory adjustments to avoid hypercapnia and acidosis, the use of sequential compression devices to minimizes venous stasis, and optimize intravascular volume to minimize the effects of increased intraabdominal pressure on renal and cardiac function.

CONCLUSIONS

Morbidly obese patients undergoing laparoscopic bariatric surgery are at risk for intraoperative complications relating to the use of CO2 pneumoperitoneum. Surgeons performing laparoscopic bariatric surgery should understand the physiologic effects of CO2 pneumoperitoneum in the morbidly obese and make appropriate intraoperative adjustments to minimize the adverse changes.