Does laparoscopy increase bacteremia and endotoxemia in a peritonitis model?

Laparoscopic versus open appendectomy: a retrospective cohort study assessing outcomes and cost-effectiveness

BACKGROUND

Appendectomy is the most common surgical procedure performed in emergency surgery. Because of lack of consensus about the most appropriate technique, appendectomy is still being performed by both open (OA) and laparoscopic (LA) methods. In this retrospective analysis, we aimed to compare the laparoscopic approach and the conventional technique in the treatment of acute appendicitis.

METHODS

Retrospectively collected data from 593 consecutive patients with acute appendicitis were studied. These comprised 310 patients who underwent conventional appendectomy and 283 patients treated laparoscopically. The two groups were compared for operative time, length of hospital stay, postoperative pain, complication rate, return to normal activity and cost.

RESULTS

Laparoscopic appendectomy was associated with a shorter hospital stay (2.7 ± 2.5 days in LA and 1.4 ± 0.6 days in OA), with a less need for analgesia and with a faster return to daily activities (11.5 ± 3.1 days in LA and 16.1 ± 3.3 in OA). Operative time was significantly shorter in the open group (31.36 ± 11.13 min in OA and 54.9 ± 14.2 in LA). Total number of complications was less in the LA group with a significantly lower incidence of wound infection (1.4 % vs 10.6 %, P <0.001). The total cost of treatment was higher by 150 € in the laparoscopic group.

CONCLUSION

The laparoscopic approach is a safe and efficient operative procedure in appendectomy and it provides clinically beneficial advantages over open method (including shorter hospital stay, decreased need for postoperative analgesia, early food tolerance, earlier return to work, lower rate of wound infection) against only marginally higher hospital costs.

TRIAL REGISTRATION

NCT02867072 Registered 10 August 2016. Retrospectively registered.

The effects of pneumoperitoneum and controlled ventilation on peritoneal lymphatic bacterial clearance: experimental results in rats

OBJECTIVE

To evaluate the effect of pneumoperitoneum, both alone and in combination with controlled ventilation, on peritoneal lymphatic bacterial clearance using a rat bacterial peritonitis model.

METHOD

A total of 69 male Wistar rats were intraperitoneally inoculated with an Escherichia coli solution (10(9) colony-forming units (cfu)/mL) and divided into three groups of 23 animals each: A (control group), B (pneumoperitoneum under 5 mmHg of constant pressure), and C (endotracheal intubation, controlled ventilation, and pneumoperitoneum as in Group B). The animals were sacrificed after 30 min under these conditions, and blood, mediastinal ganglia, lungs, peritoneum, liver, and spleen cultures were performed.

RESULTS

Statistical analyses comparing the number of cfu/sample in each of the cultures showed that no differences existed between the three groups.

CONCLUSION

Based on our results, we concluded that pneumoperitoneum, either alone or in association with mechanical ventilation, did not modify the bacterial clearance through the diaphragmatic lymphatic system of the peritoneal cavity.

Protective effect of carbon dioxide against bacterial peritonitis induced in rats

BACKGROUND

Carbon dioxide (CO(2)) has been used in the food industry as an antimicrobial agent. This study aimed to investigate whether CO(2) pneumoperitoneum might act similarly as an antimicrobial agent in the infected peritoneal cavity.

METHODS

Peritonitis was induced in 58 rats by intraabdominal injection of an Escherichia coli inoculum (6 x 105 colony-forming units [CFU]/ml). Control rats were injected with saline solution. The rats were randomly divided into four groups: rat control (RC, n = 15), bacterial inoculation control (BIC, n = 10), bacterial inoculation and laparotomy (BIL, n = 17), and bacterial inoculation and CO(2) pneumoperitoneum (BIP, n = 16). The survival rates and histopathologic changes in the abdominal wall muscles, spleen, liver, intestines, and omentum were evaluated, and the samples were classified as "preserved" or "inflamed" (acute inflammation or tissue regeneration).

RESULTS

The survival rates for the four groups were as follows: RC (100%), BIP (75%), BIL (53%), and BIC (30%). With regard to survival rates, statistically significant differences were observed between the following groups: RC and BIC (p = 0.0009), RC and BIL (p = 0.0045), BIP and BIC (p = 0.0332), and RC and BIP (p = 0.0470). No significant differences regarding survival rates were observed between the BIL and BIC groups or between the BIP and BIL groups. With regard to the number of inflamed samples per group, a statistically significant difference was observed between the BIC and RC groups and the BIL and RC groups (p = 0.05).

CONCLUSION

Carbon dioxide pneumoperitoneum has a protective effect against bacterial peritonitis induced in rats.

Laparoscopic versus open appendectomy: Which way to go?

AIM: To compare the outcome of laparoscopic versus open appendectomy.

METHODS: Prospectively collected data from 293 consecutive patients with acute appendicitis were studied. These comprised of 165 patients who underwent conventional appendectomy and 128 patients treated laparoscopically. The two groups were compared with respect to operative time, length of hospital stay, postoperative pain, complication rate and cost.

RESULTS: There were no statistical differences regarding patient characteristics between the two groups. Conversion to laparotomy was necessary in 2 patients (1.5%). Laparoscopic appendectomy was associated with a shorter hospital stay (2.2 d vs 3.1 d, P = 0.04), and lower incidence of wound infection (5.3% vs 12.8%, P = 0.03). However, in patients with complicated disease, intra-abdominal abscess formation was more common after laparoscopic appendectomy (5.3% vs 2.1%, P = 0.002). The operative time and analgesia requirements were similar in the two groups. The cost of treatment was higher by 370 € in the laparoscopic group.

CONCLUSION: Laparoscopic appendectomy is as safe and efficient as open appendectomy, provided surgical experience and equipment are available.

Development of a lethal model of peritonitis for assessment of laparoscopic and laparotomic treatments in rats

PURPOSE

Development of a lethal model of peritonitis to assess the results of treating that peritonitis using videolaparoscopy and laparotomy.

METHODS

We developed a model of peritonitis in rats using cecal ligation (CLP) against a 2-mm diameter rigid mold and puncture. Two experiments were performed: determination of seven-day lethality; and analysis of white cell counts, blood cultures and cytokines (Interleukin-1 beta, Tumor Necrosis Factor-alpha and IL-6). The animals were divided into four groups: I--Sham surgery; II--CLP; III--CLP + Videolaparoscopy; and IV--CLP + Laparotomy .

RESULTS

Seven-day lethality was 0% in group I, 80% in the group II (p<0.05), 60% in group III , and 20 % in group IV. There was a significant reduction in leukocyte counts and higher levels of serum IL-1 beta, TNF-alpha and IL-6 in the group II compared to controls. The percentages of positive blood cultures were higher after videolaparoscopic compared to laparotomic treatment.

CONCLUSION

The experimental model provoked a lethal form of peritonitis and that videolaparoscopic treatment had more bacteraemia than laparotomy.

Effect of Carbon Dioxide Pneumoretroperitoneum on Bacterial Translocation in an Experimental Retroperitoneoscopy Model

PURPOSE

To evaluate the effect of artificial CO2 pneumoretroperitoneum on bacterial translocation in an experimental retroperitoneoscopy model.

MATERIALS AND METHODS

Eighteen adult male New Zealand White rabbits weighing 2.5 to 3 kg were divided into two groups. Group 1 (control group) consisted of 6 rabbits, while the remaining 12 served as the pneumoretroperitoneum group (group 2). In group 1, the left retroperitoneal space was dissected with a 50-mL balloon without CO2 insufflation, and the animals were kept under anesthesia for 3 hours with the balloons inflated. In group 2, after balloon dissection as in group 1, CO2 insufflation was applied at 1 L/min to achieve a pressure of 10 to 12 mm Hg for 3 hours. Afterward, all animals were sacrificed, and samples were taken from the blood, retroperitoneal area, lungs, liver, mesentery, heart, kidneys, ureters, bladder, colon, small intestine, and spleen and carried to the microbiology laboratory in Carry-Blair medium. Bacterial growth was evaluated using standard techniques.

RESULTS

All animals survived the experimental procedures. None of the rabbits in the control group demonstrated any bacterial translocation in the sampled tissues. In the pneumoretroperitoneum group, one rabbit was found to have 10(2) colony-forming units of E. coli in the kidney, but this was considered to be the result of contamination, not translocation.

CONCLUSION

Carbon dioxide pneumoretroperitoneum does not seem to cause bacteremia or bacterial translocation in this experimental model. Retroperitoneoscopy probably does not create any additional risk of septic complications.

Abdominal emergencies: diagnostic and therapeutic laparoscopy

BACKGROUND

Laparoscopy has been practiced in the management of emergencies resulting from inflammatory conditions, lumenal obstruction, perforation, vascular occlusion, and trauma. This article identifies and discusses controversial areas in the field, in particular surrounding the efficacy, cost effectiveness, and perceived advantages of laparoscopy in the evaluation and treatment of patients with acute abdominal conditions.

MATERIALS AND METHODS

Review and commentary on pertinent articles in the English language literature are presented.

RESULTS

Prospective randomized trials have been reported in the treatment of some disorders, but a lack of recommendations that are evidence-based has hindered more widespread usage of laparoscopy in an emergency setting. In addition, concerns have been raised that the creation of capnoperitoneum in the patient with established peritonitis may be detrimental with respect to potentiation of bacteremia and severe sepsis, and experimental studies have yielded conflicting data in this regard.

CONCLUSION

As such issues are resolved, utilization of laparoscopy is likely to increase substantially as expertise is acquired. A minimal-access approach carries less morbidity and may offer other practical advantages in terms of surgical technique and application. When surgical intervention is appropriate, laparoscopy is now preferred for acute biliary disease. Female patients of reproductive age with acute appendicitis may benefit, particularly if there is preoperative diagnostic uncertainty. Selected cases of intestinal obstruction and visceral perforation presenting soon after symptom onset and in whom shock is absent may also be amenable to laparoscopic repair. Its use in the treatment of most trauma patients and patients with generalized peritonitis or hemodynamic instability is not recommended at present.

Bacteremia after diagnostic conventional laparoscopy and minilaparoscopy: a prospective study in 100 patients

BACKGROUND/GOALS

Diagnostic laparoscopy under sedoanalgesia is a valuable tool in the work-up of liver diseases and is helpful as a staging procedure. The rate of bacteremia caused by this procedure is unknown, in particular when performed as minilaparoscopy.

STUDY

A 100 consecutive patients having undergone diagnostic laparoscopy carried out either conventionally (group I, n=50) or as minilaparoscopy (group II, n=50) were prospectively enrolled in this study. Blood cultures were drawn before and within 5 minutes after the procedure. Risk factors for bacteremia were evaluated.

RESULTS

Bacterial growth occurred in 4 blood cultures drawn immediately after laparoscopy. No patient developed fever or other signs of infection in the follow-up. Risk factors predisposing to bacteremia could not be identified.

CONCLUSIONS

Conventional diagnostic laparoscopy under sedoanalgesia and minilaparoscopy are associated with a low rate of bacteremia as in diagnostic upper endoscopy.

Effect of intraperitoneal application of an endotoxin inhibitor on survival time in a laparoscopic model of peritonitis in rats

Gram-negative sepsis due to fecal peritonitis is a hazardous disease with a high percentage having a lethal course. The inflammatory effects are induced by endotoxin release. We performed this study to evaluate the potential of direct intraperitoneal application of an endotoxin inhibitor in a laparoscopic peritonitis model in rats. The human feces specimen was prepared, and a standard fecal specimen (0.5 ml/kg b.w.) was applied via minilaparotomy. The rats were randomized to two studies. First, rats were randomized to three groups to define the survival time: (1) rats without further manipulation; (2) rats with laparoscopic lavage using NaCl; (3) rats with laparoscopic lavage using endotoxin inhibitor. Second, rats underwent the same procedure used in the first part of the study and an additional group with only NaCl lavage without peritonitis was randomized. To evaluate the immunologic or biochemical effects, animals were killed at a standard time of 20 hours until the postmortem examination was established. Interleukins 6 and 10 (IL-6, IL-10), malondialdehyde, and protein carbonyl group levels in plasma and particularly in peritoneal fluid were assayed. The first part of the experiment showed significantly increased survival after endotoxin inhibitor lavage. In the second part, administration of endotoxin inhibitor intraperitoneally caused a significant reduction of IL-6 in the peritoneal fluid, in contrast to that in the other groups. Laparoscopic application of endotoxin inhibitor intraperitoneally thus produced a beneficial effect on survival and reduction of IL-6 in peritoneal fluid. Hence, it is possible to influence the inflammation cascade by causing intraperitoneal endotoxin inhibition.

The increased incidence of intraabdominal infections in laparoscopic procedures: potential causes, postoperative management, and prospective innovations

We conducted a review of the literature to identify some potential causes for the increased incidence of intraabdominal infections seen after laparoscopic procedures. We also discuss the postoperative management of this condition and provide a prospective overview of innovations that may be helpful in such cases in the future.

Trends in utilization and outcomes of laparoscopic versus open appendectomy

BACKGROUND

Although a number of trials have analyzed the outcomes of laparoscopic versus open appendectomy, the clinical advantages, and cost-effectiveness of laparoscopic appendectomy in the management of acute and perforated appendicitis are still not clearly defined. The aim of this study was to examine utilization and outcomes of laparoscopic versus open appendectomy using a national administrative database of academic medical centers and teaching hospitals.

METHODS

Using ICD-9 diagnosis and procedure codes, we obtained data from the University HealthSystem Consortium Clinical Data Base for all patients who underwent appendectomy for acute and perforated appendicitis between 1999 and 2003 (n = 60,236). Trends in utilization of laparoscopic appendectomy were examined over the 5-year period. The outcomes of laparoscopic and open appendectomy were compared including length of hospital stay, 30-day readmission, complications, observed and expected (risk-adjusted) in-hospital mortality, and costs.

RESULTS

Overall, 41,085 patients underwent open appendectomy and 19,151 patients underwent laparoscopic appendectomy. The percentage of appendectomy performed by laparoscopy increased from 20% in 1999 to 43% in 2003 (P <0.01). Compared with patients who underwent open appendectomy, patients who underwent laparoscopic appendectomy were more likely female, more likely white, had a lower severity of illness, and were less likely to have perforated appendicitis. Laparoscopic appendectomy was associated with a shorter length of hospital stay (2.5 days vs 3.4 days), lower rate of 30-day readmission (1.0% vs 1.3%), and lower rate of overall complications (6.1% vs 9.6%). There was no significant difference in the observed to expected mortality ratio between laparoscopic and open appendectomy (0.5 vs 0.6, respectively). The mean cost per case was similar between the two groups (US$ 6,242 vs US$ 6,260).

CONCLUSIONS

Utilization of laparoscopic appendectomy at academic centers has increased more than two-fold between 1999 and 2003. Patients selected for laparoscopic appendectomy have less advanced appendicitis and have a shorter length of stay and fewer complications without increasing the inpatient care cost.

Increased transperitoneal bacterial translocation in laparoscopic surgery

BACKGROUND

The indications for laparoscopic surgery have expanded to include diseases possibly associated with peritonitis such as appendicitis, perforated peptic ulcers, and diverticulitis. The safety of carbon dioxide (CO2) pneumoperitoneum in the presence of peritonitis has not been proved. Our previous investigations demonstrated increased bacteremia associated with CO2 insufflation. In effort to clarify the relative effects of intraabdominal pressure and type of gas, this study was designed to measure bacterial translocation with different gases at different pressures of pneumoperitoneum.

METHODS

For this study, 110 rats were given intraperitoneal bacterial innoculations with Escherichia coli and equally divided into five groups of 20 animals each. The study groups included a control group with no pneumoperitoneum administered (n = 30), insufflation at a commonly used pressure of 14 mmHg with helium (n = 20) and CO2 (n = 20), and low insufflation at 3 mmHg with helium (n = 20) and CO2 (n = 20) in an effort to minimize influences related to pressure. Blood cultures were checked at 15-min intervals for the first 45 min, then hourly thereafter for a total of 165 min after peritoneal inoculation with 2 x 10(7) E. coli.

RESULTS

There is increased risk of bacterial translocation in comparing groups that underwent pneumoperitoneum with those that did not in the rat peritonitis model. Furthermore, these findings are dependent on the presence or absence of gas, but not necessarily on the type of gas used for insufflation. In the low-pressure groups of both gases (helium and CO2), bacterial translocation was significantly increased, as compared with the control group. Low pressure also was associated with increased bacterial translocation, as compared with high pressure, but beyond 30 min of insufflation, no significant differences were apparent.

CONCLUSIONS

The risk of bacterial translocation in the E. coli rat peritonitis model is increased with insufflation using CO2 or helium, and this effect is more significant at lower pressures (3 mmHg) than at higher pressures (14 mmHg). However, no clinically applicable conclusions regarding the relative effects from type of gas or insufflation pressures could be confirmed.

Repetitive pneumoperitoneum with ozonized oxygen as a preventive in lethal polymicrobial sepsis in rats

The aim of this study was to test whether repetitive pretreatments of rats with ozonized oxygen at relatively low gas volumes into the abdomen (20 ml per rat per day) have any beneficial or detrimental effects on the course of a polymicrobial-induced lethal peritonitis. Peritonitis was induced in a surgical or a nonsurgical model by usage of fecal material from the cecum. As the biological read out we used the mortality analysis. To include possible mechanisms by which ozone might influence the septic outcome, we characterized the gene expression of the pro-inflammatory cytokines IL-1beta, IL-2, and TNF-alpha mRNA in lymphoid organs. In both models, we found a significant beneficial influence of a dose-dependent O(2)/O(3 )pneumoperitoneum on the survival rate when compared to control animals or to room air. The ozone-enhanced survival seems to be independent from altered cytokine expression because there were no differences noticed in the levels of bacterial-induced gene expression of IL-1beta and TNF-alpha in septic animals pretreated with ozonized oxygen when compared to control animals.

The effect of the pneumoperitoneum on the peritoneal defense mechanisms in diabetic rats

To investigate the effects of pneumoperitoneum on the peritoneal defense mechanism induced by streptozocin infusion during laparoscopic surgery in diabetic rats and to show the importance of regulation of diabetes for peritoneal defense mechanisms. One hundred twenty-six Sprague-Dawley male rats were allocated into six groups each consisting of 21 rats: group 1, nondiabetic sham laparotomy (control); group 2, nondiabetic pneumoperitoneum (control); group 3, uncontrolled diabetes plus sham laparotomy; group 4, controlled diabetes plus sham laparotomy; group 5, uncontrolled diabetes plus pneumoperitoneum; and group 6, controlled diabetes plus pneumoperitoneum. Diabetes was constituted by intraperitoneal infusion of one dose of 60 mg/kg streptozotocin, and diabetes was regulated (in groups 4 and 6) by subcutaneous injection of 10 IU/kg insulin in the morning and evening after the blood glucose measurements since the fourth day. Peritoneal fluid samples were taken at the zero, second, and sixth hours after sham laparotomy for groups 1, 3, and 4 and after pneumoperitoneum for groups 2, 5, and 6 on the seventh day. Total peritoneal cell count, antibacterial activity of the peritoneal fluid, and types of phagocytic cells in the peritoneal fluid were assessed. Peritoneal cell count was found to be lower in uncontrolled diabetes due to high blood glucose levels (>200 mg/dL), which led to slow migration of phagocytic cells into the peritoneum. Pneumoperitoneum had augmented the effect on phagocytic cell migration to the peritoneum compared with the sham laparotomy in controlled diabetic rats. Uncontrolled and controlled diabetes have adverse effects on peritoneal defense mechanism killing functions by interfering with the antimicrobial activity of peritoneal fluid.

Laparoscopic appendectomy for perforated appendicitis

Although laparoscopic appendectomy for uncomplicated appendicitis is feasible and safe, its application to perforated appendicitis is uncertain. A retrospective study of all patients with perforated appendicitis from 1992 to 1999 in a university hospital was performed. A series of 231 patients were diagnosed as having perforated appendicitis. Of these patients, 85 underwent laparoscopy (LA), among whom 40 (47%) required conversion to an open procedure. An open appendectomy (OA) was performed in 146 patients. The operating time was similar for the two groups. Return of fluid and solid diet intake were faster in LA than OA patients (p < 0.01). Postoperative infections including wound infections and abdominal abscesses occurred in 14% of patients in the laparoscopy group and in 26% of those with OA (p < 0.05). The surgeon's experience correlated with the conversion rate. Laparoscopic appendectomy is associated with a high conversion rate for perforated appendicitis. If successful, it offers patients faster recovery and less risk of infectious complications.

The effects of hemodynamic shock and increased intra-abdominal pressure on bacterial translocation

BACKGROUND

We hypothesized that hemorrhagic shock followed by the abdominal compartment syndrome (ACS) resulted in bacterial translocation (BT) from the gastrointestinal (GI) tract.

METHODS

Nineteen Yorkshire swine (20-30 kg) were divided into two groups. In the experimental group, group 1 (n = 10), animals were hemorrhaged to a mean arterial pressure (MAP) of 25-30 mm Hg for a period of 30 minutes and resuscitated to baseline MAP. Subsequently, intra-abdominal pressure (IAP) was increased to 30 mm Hg above baseline by instilling sterile normal saline into the peritoneal cavity. The IAP was maintained at this level for 60 minutes. Acid/base status, gastric mucosal ph (pHi), superior mesenteric artery (SMA) blood flow, and hemodynamic parameters were measured and recorded. Blood samples were analyzed by polymerase chain reaction (PCR) for the presence of bacteria. Spleen, lymph node, and portal venous blood cultures were obtained at 24 hours. Results were analyzed by ANOVA and are reported as mean +/- SEM. The second group was the control. These animals did not have the hemorrhage, resuscitation, or intra-abdominal hypertension (IAH) but were otherwise similar to the experimental group in terms of laparotomy and measured parameters.

RESULTS

SMA blood flow in group 1 (baseline of 0.87 +/- 0.10 l/min) decreased in response to hemorrhage (0.53 +/- 0.10 l/min, p = 0.0001) and remained decreased with IAH (0.63 l/min +/- 0.10, p = 0.0006) as compared to control and returned towards baseline (1.01 +/- 0.5 l/min) on relief of IAH. pHi (baseline of 7.21 +/- 0.03) was significantly decreased with hemorrhage (7.04 +/- 0.03, p = 0.0003) and decreased further after IAH (6.99 +/- 0.03, p = 0.0001) in group 1 compared to control, but returned toward baseline at 24 hours (7.28 +/- 0.04). The mean arterial pH decreased significantly from 7.43 +/- 0.01 at baseline to 7.27 +/- 0.01 at its nadir within group 1 (p = 0.0001) as well as when compared to control (p = 0.0001). Base excess was also significantly decreased between groups 1 and 2 during hemorrhage (3.30 +/- 0.71 vs. 0.06 +/- 0.60, p = 0.001) and IAH (3.08 +/- 0.71 vs. -1.17 +/- 0.60, p = 0.0001). In group 1, 8 of the 10 animals had positive lymph node cultures, 2 of the 10 had positive spleen cultures, and 2 of the 10 had positive portal venous blood cultures for gram-negative enteric bacteria. Only 2 of the 10 animals had a positive PCR. In group 2, five of the nine animals had positive lymph node cultures, zero of the nine had positive spleen cultures, and one of the nine had positive portal venous blood cultures. Two of the nine animals had positive PCRs. There was no significant difference in cultures or PCR results between the two groups (Fisher's exact test, p = 0.3).

CONCLUSION

In this study, hemorrhage followed by reperfusion and a subsequent insult of IAH caused significant GI mucosal acidosis, hypoperfusion, as well as systemic acidosis. These changes did not appear to be associated with a significant bacterial translocation as judged by PCR measurements, tissue, or blood cultures.

Laparoscopic surgery and surgical infection

Laparoscopic surgery (LS) has improved our knowledge of some aspects of surgical physiopathology. Other advantages include a lower incidence of postoperative infections, as evidenced by a lower inflammatory response which is related to a better preserved immune response to infection. But, the differential aspects of LS may influence the intraperitoneal environment and, in case of infection, must be evaluated in two different situations: during clean and potentially-contaminated surgery or in the presence of established infection. The most important differential factors of LS are the pneumoperitoneum and the use of CO2. The influence of both these on the evolution of an intraperitoneal infecton has been of interest in recent years. Our department developed an experimental study with mice to evaluate the local and systemic inflammatory response to perioperative intra-abdominal contamination with a known inoculum of Escherichia coli. The animals were distributed in four groups: control, laparotomy, laparoscopy with CO2 pneumoperitoneum, and laparoscopy with wall traction. Peritoneal liquid and blood cultures such as peritoneal and systemic cytokine levels were analyzed. The results showed a better tolerance to perioperative contamination in LS groups while the CO2 pneumoperitoneum had no influence. But, in the presence of peritonitis, an elevated CO2 pneumoperitoneum can be dangerous and the operative time is an important factor to be considered. The literature is reviewed on the relationship between LS and surgical infection.

Bedside laparoscopy in the ICU: report of four cases

BACKGROUND

Patients in the intensive care unit (ICU) may suffer from life-threatening abdominal pathologies, which may necessitate a surgical intervention. Diagnosis may be difficult, as deep sedation and analgesia often mask symptoms, and physical examination is unreliable. Imaging studies are not accurate enough, and exploratory laparotomy carries significant morbidity and mortality rates in this patient population. The unstable patient is difficult to mobilize to the imaging department or to the operating room. Bedside laparoscopy may overcome these difficulties.

PATIENTS AND METHODS

We describe our initial experience with the use of bedside laparoscopy in critical patients with suspected abdominal pathology. The procedure was performed in four patients over a 4-month period and completed in all four.

RESULTS

The findings were: turbid fluid consistent with viscus perforation in a patient with unexplained sepsis after cardiac surgery, sterile hemorrhagic fluid in a patient with malignancy and thrombotic thrombocytopenia purpura, a retroperitoneal mass from which biopsies were taken in a patient with sudden respiratory failure, and abdominal abscess in a patient after bowel resection for mesenteric embolism. None of these patients had a laparotomy after the laparoscopy. Patients 1 and 4 died a few hours after the procedure from sepsis, and patients 2 and 3 died several days later.

CONCLUSION

Bedside laparoscopy in the ICU is feasible, informative, and accurate. It has a role in diagnosing abdominal pathologies and planning further treatment. It may avert a nontherapeutic laparotomy. Unfortunately, the prognosis in these patients is poor. Earlier use of this diagnostic modality may improve patient outcome.

Effect of CO2 pneumoperitoneum on the systemic and peritoneal cytokine response in a LPS-induced sepsis model

We studied the effect of carbon dioxide (CO2) pneumoperitoneum on the systemic and peritoneal cytokine response in a rat model of intraperitoneal sepsis. After intraperitoneal injection of bacterial lipopolysaccharide (LPS, 10 mg/kg), rats were divided into 3 groups (n = 49 in each group): control (abdominal puncture); CO2 pneumoperitoneum, and laparotomy. Blood and peritoneal lavage fluid (PLF) were sampled at 0, 1, 2, 3, 4, 6, and 8 h after LPS challenge. Blood cell counts, plasma endotoxin level, and the levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6 (IL-6) in the plasma and PLF were measured. Blood cell counts did not differ between the 3 groups. Plasma endotoxin levels in the pneumoperitoneum group were significantly increased immediately after the procedure (p < 0.05). Although peak plasma TNF-alpha levels in the pneumoperitoneum group were seen immediately after the procedure, other changes in plasma cytokine levels did not differ significantly between the 3 groups. PLF TNF-alpha and IL-1beta levels in the pneumoperitoneum group were significantly lower than levels in the control and laparotomy groups soon after the procedure (p < 0.05). PLF IL-6 levels in the pneumoperitoneum group tended to be lower than those in the laparotomy group. In conclusion, CO2 pneumoperitoneum might induce different responses between systemic and peritoneal cytokines soon after the procedure in a rat model of intraperitoneal sepsis.

The impact of conventional and laparoscopic colon resection (CO2 or helium) on intraperitoneal adhesion formation in a rat peritonitis model

BACKGROUND

Although postoperative intra-abdominal adhesion formation has been shown to be less with laparoscopic procedures than with open surgery, the extent of intraperitoneal adhesion formation after open and laparoscopic colon resection in patients with intra-abdominal infection remains unclear.

METHODS

A standardized fecal inoculum was intraperitoneally applied in 72 rats to induce peritonitis. The rats were randomized into four groups. The three experimental groups underwent laparoscopic resection of the cecum with carbon dioxide (n = 20) or helium (n = 20) insufflation at a pressure of 8 mmHg, or conventional open cecum resection (n = 20). In the control group, no further manipulations were performed after induction of the peritonitis (n = 12). Blood samples were taken during the perioperative course to determine the plasma levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10). The number of intraperitoneal adhesions and the bacterial species of peritoneal swabs were determined in each animal.

RESULTS

The adhesions were increased in all operation groups as compared with the control group. The number of adhesions was significantly greater after conventional resection than after laparoscopic approaches (p < 0.01). The overall adhesion score was significantly lower in the helium group (p < 0.05) than in the two other operation groups. There was no difference between the laparotomy and carbon dioxide groups. Whereas postoperative TNF-alpha plasma levels were decreased, IL-10 levels were significantly greater in the helium group than in the other three groups.

CONCLUSIONS

Intraperitoneal infection is reducing the benefit of laparoscopic surgery regarding postoperative adhesions. Although laparoscopic resection showed an advantage in the number of adhesions with both gases, the total adhesion score was lowest in the helium group.

Is helium insufflation superior to carbon dioxide insufflation in bacteremia and bacterial translocation with peritonitis?

PURPOSE

To evaluate the effects of CO2 or helium insufflation on bacteremia and bacterial translocation in rats with peritonitis.

MATERIALS AND METHODS

Forty male Wistar-Albino rats were divided into four groups, each containing 10 rats. The rats in the first group were injected only with E. coli into their peritoneal cavities with no further manipulation. The second group, following E. coli injection, underwent midline laparotomy without manipulation of the viscera for 1 hour. After the injection of E. coli in the third and fourth groups, CO2 and helium pneumoperitoneum, respectively, were maintained for 1 hour under 14 mm Hg pressure. At the end of the sixth hour, tissue samples were taken from the liver, spleen, lung, and mesenteric lymph nodes in order to evaluate bacterial translocation. During the study, blood samples were taken from each rat at 0, 1, 2, 4, and 6 hours to demonstrate bacteremia.

RESULTS

There was a significant increase in bacteremia in the CO2 pneumoperitoneum group compared with the laparotomy-only and helium groups at 1 and 2 hours. Although all the blood samples at the fourth hour were positive for E. coli in every rat of all groups, helium was associated with a lower incidence of bacteremia at the sixth hour compared with other groups (P < 0.05). The CO2 pneumoperitoneum caused bacterial translocation to all organs from which tissue samples were taken. Although there was an insignificant decrease in translocation to the liver, spleen, and lung with helium compared with CO2 insufflation, helium did not increase bacterial translocation to the spleen compared with laparotomy alone, as did CO2 (P < 0.05).

CONCLUSION

Helium might be an alternative to CO2 insufflation in patients with peritonitis if these results are confirmed by further experimental and clinical trials.

DESENVOLVIMENTO DE MODELO DE PERITONITE BACTERIANA PARA AVALIAÇÃO DO TRATAMENTO MEDIANTE ACESSO LAPAROTÔMICO E VIDEO-LAPAROSCÓPICO

Introdução: O emprego do acesso videolaparoscópico no tratamento das afecções digestivas que cursam com peritonite generalizada é motivo de controvérsia. Objetivo: Desenvolver um modelo de peritonite bacteriana para avaliação do tratamento mediante acesso laparotômico e videolaparoscópico. Métodos: Ratos machos Wistar foram submetidos à ligadura de ceco (CLP) sob molde rígido de 3mm de diâmetro; na seqüência foram feitas 14 punções no ceco com agulha 15X10. Após 6 horas de indução da peritonite, os animais foram tratados mediante laparotomia ou videolaparoscopia e avaliados com base nas hemoculturas e na taxa de mortalidade. O tratamento consistiu de tiflectomia seguida ou não de lavagem da cavidade peritoneal com solução fisiológica. Resultado: A mortalidade após CLP sem tratamento foi de 90% em uma semana. As hemoculturas positivas para bactérias após 3 horas variaram de 80 a 100% e após 24 horas de 60 a 80%, nos animais tratados com laparotomia sem lavagem do peritôneo e com videolaparoscopia seguida ou não de lavagem peritoneal. Todavia, a mortalidade após laparotomia foi de 20% e após videolaparoscopia foi de 80%. Conclusão: O modelo experimental desenvolvido induz a peritonite grave, e a bacteremia associada ao tratamento videolaparoscópico tem alta letalidade.

Lavage by laparoscopy fares better than lavage by laparotomy: experimental evidence

BACKGROUND

Although carbon dioxide (CO2) pneumoperitoneum is proposed increasingly for treatment of secondary peritonitis, associated deleterious effects have been reported in experimental models, with the hypothesis that increased intraperitoneal pressure might facilitate bacterial translocation. The purpose of this study was to compare the outcome (and qualitative microbiologic analysis) from peritonitis in rats after lavage by laparoscopy with the outcome after lavage by laparotomy.

METHODS

After determination of the standard innoculum for this study in 30 animals, 120 male Wistar rats received 1 ml of Escherichi coli 10(6) colony-forming unit (CFU), Bacteroides fragilis 10(7) CFU, Enterococcus faecalis 10(7) CFU in a sterile rat feces-barium sulfate suspension adjuvant, were anesthetized with intramuscular ketamine, and then underwent peritoneal lavage by either laparotomy (n = 60) or laparoscopy (n = 60). The duration of peritonitis defined two groups: group A: duration less than 3 h (n = 20) and group B: duration 3 h or more (n = 40). Both groups underwent successive lavage with 10-ml aliquots (total, 50 ml) of 0.9% saline solution at 37 degrees C. Five 2-ml samples of liquid lavage were drawn for culture and microbiologic analysis. Blood (0.2 ml) and peritoneal liquid lavage samples were incubated 48 h at 37 degrees C and cultured.

RESULTS

All the animals survived. Mean duration of peritoneal lavage was 13.2 min (range, 6-25 min) for laparoscopy and 9.7 min (range, 6-15 min) and for laparotomy. The difference was not statistically significant. The mean duration of operation was significantly longer with laparoscopy than with laparotomy: 44.5 min (range, 35-62 min) and 25 min (range, 16-40 min), respectively (p = 0.0001). The collected lavage volumes were not statistically different: 48.5 ml (range, 40-54 ml) and 46.7 ml (range, 37-56 ml), respectively. No statistically significant differences were found between the laparoscopy and laparotomy groups in terms of E. coli bacteremia, irrespective of peritonitis duration. The rates of positive blood culture for B. fragilis and E. faecalis were signficantly lower after laparoscopy than after laparotomy, both in the overall group (p = 0.025 and p = 0.045, respectively) and when duration of peritonitis exceeded 3 h (p = 0.001 and p = 0.044, respectively).

CONCLUSIONS

In this animal model of secondary peritonitis, lavage by laparoscopy was associated with less bacteremia for B. fragilis and E. faecalis than peritoneal lavage by laparotomy.

Laparoscopic surgery and surgical infection

INTRODUCTION

It has been observed that the metabolic response to surgical injury is less after laparoscopic surgery than after open surgery. However, the effect of laparoscopic surgery on surgical infection has not been given much attention in the surgical literature, even though it may decrease the incidence of infectious complications. The objective of this study was to assess the influence that laparoscopic surgery has on surgical infection and to highlight certain controversial aspects.

METHODS

A review of the literature was undertaken to examine the relationship between laparoscopic surgery and surgical infection. This was achieved primarily by using PubMed Medline as a source of material.

RESULTS AND CONCLUSION

Laparoscopic surgery is associated with better preservation of the immune system than open surgery. This results in a decreased incidence of infectious complications. Although carbon dioxide pneumoperitoneum affects the peritoneal response to injury, it seems to have no harmful effect in terms of intra-abdominal infection. Nevertheless, at laparoscopic operation the virulence of intestinal micro-organisms should be recognized and, while knowing the advantages of minimally invasive surgery, the surgeon should consider the complexity of this technique. Furthermore, maintenance of laparoscopic instruments should be governed by the same norms as those used in open surgery; recommendations offered by the manufacturers should be respected.

Impact of laparoscopy with carbon dioxide versus helium on local and systemic inflammation in an animal model of peritonitis

Increased intraperitoneal pressure and insufflation of carbon dioxide during laparoscopy may cause sepsis by promoting systemic inflammation in patients with intra-abdominal inflammatory diseases. The influence of carbon dioxide and helium during laparoscopy on bacteremia, endotoxemia, the plasma concentration of tumor necrosis factor-alpha (TNF-alpha), TNF-alpha secretion ex vivo by peripheral blood mononuclear cells (PBMCs), and intraperitoneal abscess formation was investigated in an animal model. A standardized fecal inoculum was injected intraperitoneally, and rats underwent laparoscopy with either carbon dioxide (N = 20) or helium (N = 20) or no further manipulation (control group; N = 20). Bacteremia was significantly more common 1 hour after laparoscopy with CO2 than in animals receiving helium or the control group. Furthermore, helium use led to a significant decrease of bacteremia 1 week after intervention. Fecal inoculation caused significant leukocytopenia in all groups within 1 hour after intervention, with complete recovery only in the helium-treated group (p < 0.05). The TNF-alpha plasma concentration was significantly lower in the helium-treated group, and suppression of ex vivo production recovered only in the animals undergoing laparoscopy with helium (p < 0.05). The number of intraperitoneal abscesses was significantly lower after laparoscopy with helium (2+/-1.5) than after CO2 laparoscopy (6.3+/-5.1) or in the control group (5.2+/-4.8). Laparoscopy with CO2 increased systemic inflammation only slightly, while helium use was associated with a significant lower incidence of bacteremia and local and systemic inflammation compared with the control group.

The effect of a high partial pressure of carbon dioxide environment on metabolism and immune functions of human peritoneal cells-relevance to carbon dioxide pneumoperitoneum

OBJECTIVE

Our purpose was to evaluate in vitro the effect of a high partial pressure of carbon dioxide environment used in laparoscopy on metabolic and immune response of various human peritoneal cells.

STUDY DESIGN

Polymorphonuclear leukocytes were obtained from 5 healthy volunteers, peritoneal macrophages were obtained from the effluent of 8 patients undergoing continuous ambulatory peritoneal dialysis, and human peritoneal mesothelial cell cultures were prepared from omentum derived from 5 patients undergoing elective surgery. The cells were exposed to a laparoscopy-like environment (1 atmosphere carbon dioxide and 0.2 atmosphere oxygen), to a control gas mixture (1 atmosphere helium and 0.2 atmosphere oxygen), or air for 3 hours. After exposure to gas mixtures, cell functions were tested at various recovery periods.

RESULTS

Three hours of exposure to a high partial pressure of carbon dioxide had no effect on viability of peritoneal macrophages and human peritoneal mesothelial cells, tested by trypan blue dye uptake and lactate dehydrogenase release. A high partial pressure of carbon dioxide decreased the mitochondrial dehydrogenases activity of peritoneal macrophages and human peritoneal macrophage cells by 60%, assayed by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide reduction. High partial pressure of carbon dioxide blocked the superoxide release from activated polymorphonuclear leukocytes and the secretion of interleukin 1beta from stimulated peritoneal macrophages, and human peritoneal macrophage cells were decreased by 15% and 30% and the secretion of tumor necrosis factor-alpha from peritoneal macrophages was suppressed by 85%. Mitochondrial activity, polymorphonuclear leukocyte function, and interleukin 1beta and tumor necrosis factor-alpha secretion returned to normal after a recovery period of 12 to 24 hours, 4.5 hours, and 24 hours, respectively. In the control experiments exposure of cells to helium had no suppressive effect.

CONCLUSIONS

Exposure of cells to a high partial pressure of carbon dioxide environment suppresses the inflammatory and metabolic responses of peritoneal cells. We suggest that this suppressive effect may contribute to the low postsurgery adhesion formation and the reduction in postoperative pain observed in laparoscopy. Nevertheless, the suppression of the immune response should also be taken into account for operations involving a high risk of bacterial dissemination.

Minimally invasive anterior retroperitoneal approach to the lumbar spine. Emphasis on the lateral BAK

STUDY DESIGN

Eighteen patients with lumbar instability from fractures, postlaminectomy syndrome, or infection were treated prospectively with minimally invasive retroperitoneal lumbar fusions.

OBJECTIVES

To determine if interbody Bagby and Kuslich fusion cages and femoral allograft bone dowels can be inserted in a transverse direction via a lateral endoscopic retroperitoneal approach to achieve spinal stability.

SUMMARY OF BACKGROUND DATA

Endoscopic spinal approaches have been used to achieve lower lumbar fusion when instrumentation is placed through a laparoscopic, transperitoneal route. However, complications of using this approach include postoperative intra-abdominal adhesions, retrograde ejaculation, great vessel injury, and implant migration. This study is the first clinical series investigating the use of the lateral retroperitoneal minimally invasive approach for lumbar fusions from L1 to L5.

METHODS

Eighteen patients underwent anterior interbody decompression and/or stabilization via endoscopic retroperitoneal approaches. In most cases, three 12-mm portals were used. Two parallel transverse interbody cages restored the neuroforaminal height and the desired amount of lumbar lordosis was achieved by inserting a larger anterior cage, distraction plug, or bone dowel.

RESULTS

The overall morbidity of the procedure was lower than that associated with traditional "open" retroperitoneal or laparotomy techniques, with a mean length of hospital stay of 2.9 days (range, outpatient procedure to 5 days). The mean estimated intraoperative blood loss was 205 cc (range, 25-1000 cc). There were no cases of implant migration, significant subsidence, or pseudoarthrosis at mean follow-up examination of 24.3 months (range, 12-40 months) after surgery.

CONCLUSIONS

This preliminary study of 18 patients illustrates that endoscopic techniques can be applied effectively through a retroperitoneal approach with the patient in the lateral position. Unlike the patients who had undergone transperitoneal procedures described in previous reports, in these preliminary 18 patients, there were no cases of retrograde ejaculation, injury to the great vessels, or implant migration.

Laparoscopic versus open appendectomy: a metaanalysis

BACKGROUND

There have been numerous retrospective and uncontrolled series of laparoscopic appendectomy (LA), as well as 16 prospective randomized studies published to date. Although most of these have concluded that the laparoscopic technique is as least as good as open appendectomy (OA), there has been considerable controversy as to whether LA is superior. To help clarify this issue, we performed a metaanalysis of the randomized prospective studies.

STUDY DESIGN

A metaanalysis of all formally randomized prospective trials of LA versus OA in adults.

RESULTS

A total of 1,682 patients were analyzed. When compared with OA, LA results in significantly less postoperative pain, earlier resumption of solid foods, a shorter hospital stay, and a faster return to normal activities. The wound infection rate in the LA patients is less than one half the rate in patients undergoing OA. LA, however, requires longer operating times and the incidence of intraabdominal abscess is higher, but this failed to reach statistical significance. There were no differences in complications or hospital charges.

CONCLUSIONS

LA offers considerable advantages over OA, primarily because of its ability to reduce the incidence of wound infections and shorten recovery times. Its widespread acceptance should be considered. The trend toward increased intraabdominal abscess formation is worrisome, however, and demands further investigation.