Native Whey Induces Similar Post Exercise Muscle Anabolic Responses as Regular Whey, Despite Greater Leucinemia, in Elderly Individuals

OBJECTIVE

Elderly muscle seems less sensitive to the anabolic stimulus of a meal. Changes in blood concentrations of leucine are suggested as one important trigger of the anabolic response in muscle. The aim of this study was to investigate whether native whey protein, containing high amounts of leucine, may be a more potent stimulator of muscle protein synthesis (MPS) in elderly than regular whey protein (WPC-80) or milk.

DESIGN

Randomized controlled partial crossover.

SETTING

Norwegian School of Sport Sciences.

PARTICIPANTS

21 healthy elderly men and women (≥70 years).

INTERVENTION

Participants received either 20 g of WPC-80 and native whey (n = 11) on separate days in a crossover design, or milk (n = 10). Supplements were ingested immediately and two hours after a bout of lower body heavy-load resistance exercise.

MEASUREMENTS

Blood samples and muscle biopsies were collected to measure blood concentrations of amino acids by gas-chromatography mass spectrometry (GCMS), phosphorylation of p70S6K, 4E-BP1 and eEF-2 by immunoblotting and mixed muscle fractional synthetic rate (FSR) by use of [2H5]phenylalanine-infusion, GCMS and isotope-ratio mass spectrometry.

RESULTS

Native whey increased blood leucine concentrations more than WPC-80 (P < 0.05), but not p70S6K phosphorylation or mixed muscle FSR. Both whey supplements increased blood leucine concentrations (P < 0.01) and P70S6K phosphorylation more than milk (P = 0.014). Native whey reached higher mixed muscle FSR values than milk (P = 0.026) 1-3h after exercise.

CONCLUSIONS

Despite greater increases in blood leucine concentrations than WPC-80 and milk, native whey was only superior to milk concerning increases in MPS and phosphorylation of P70S6K during a 5-hour post-exercise period in elderly individuals.

Long-term outcome after early repair of iatrogenic bile duct injury. A national Danish multicentre study

BACKGROUND

The aim of this retrospective study was to evaluate the peri-operative and long-term outcome after early repair with a hepaticojejunostomy (HJ).

METHODS

Between 1995 and 2010, a nationwide, retrospective multi-centre study was conducted. All iatrogenic bile duct injury (BDI) sustained during a cholecystectomy and repaired with HJ in the five Hepato-Pancreatico-Biliary centres in Denmark were included.

RESULTS

In total, 139 patients had an HJ repair. The median time from the BDI to reconstruction was 5 days. A concomitant vascular injury was identified in 26 cases (19%). Post-operative morbidity was 36% and mortality was 4%. Forty-two patients (30%) had a stricture of the HJ. The median follow-up time without stricture was 102 months. Nineteen out of the 42 patients with post-reconstruction biliary strictures had a re-HJ. Twenty-three patients were managed with percutaneous transhepatic cholangiography and dilation. The overall success rate of re-establishing the biliodigestive flow approached 93%. No association was found between timing of repair, concomitant vascular injury, level of injury and stricture formation.

CONCLUSION

In this national, unselected and consecutive cohort of patients with BDI repaired by early HJ we found a considerable risk of long-term complications (e.g. 30% stricture rate) and mortality in both the short- and the long-term perspective.

Abnormal plasma sodium concentrations in patients treated with desmopressin for cranial diabetes insipidus: results of a long-term retrospective study

CONTEXT AND OBJECTIVE

Patients with cranial diabetes insipidus (CDI) are at risk of developing both hypernatraemia and hyponatraemia, due to the condition itself or secondary to treatment with vasopressin-analogues or during administration of i.v. fluids. We aimed to assess the frequency and impact of dysnatraemias in the inpatient (INPT) and outpatient (OPT) setting in desmopressin-treated CDI, comparing those with normal thirst with those with abnormal thirst.

DESIGN

The study included 192 patients with cranial diabetes, who were identified from the Beaumont Pituitary Database, a tertiary referral centre. Retrospective case note audit was performed and the clinical and biochemical information of 147 patients with CDI were available for analysis.

RESULTS

A total of 4142 plasma sodium measurements for 137 patients with normal thirst, and 385 plasma sodium measurements for ten patients with abnormal thirst were analysed. In those with normal thirst, the most common OPT abnormality was mild hyponatraemia (pNa(+) 131-134  mmol/l) in 27%, while 14.6% had more significant hyponatraemia (pNa(+) ≤130  mmol/l). Of those patients with normal thirst, 5.8% were admitted due to complications directly related to hyponatraemia. Compared with patients with normal thirst, those with abnormal thirst were more likely to develop significant OPT hypernatraemia (20% vs 1.4%, P=0.02) and significant INPT hyponatraemia (50% vs 11.1%, P 0.02).

CONCLUSION

OPT management of CDI is complicated by a significant incidence of hyponatraemia. In contrast, OPT hypernatraemia is almost exclusively a complication seen in adipsic CDI, who also had more frequent INPT hyponatraemia. CDI associated with thirst disorder requires increased physician attention and patient awareness of potential complications.

Immunosuppression after liver transplantation for primary sclerosing cholangitis influences activity of inflammatory bowel disease

BACKGROUND & AIMS

Previous studies have shown conflicting results regarding the course of inflammatory bowel disease (IBD) after liver transplantation in patients with primary sclerosing cholangitis (PSC). We studied the progression of IBD in patients with PSC who have undergone liver transplantation. We also studied risk factors, including medical therapy, that could influence on IBD disease activity.

METHODS

In a longitudinal multicenter study, we analyzed data from the Nordic Liver Transplant Group on 439 patients with PSC who underwent liver transplantation from November 1984 through December 2006; 353 had IBD at the time of transplantation. We compared IBD activity before and after liver transplantation. Two hundred eighteen patients who had an intact colon and had undergone pretransplant and post-transplant colonoscopies were characterized further.

RESULTS

Macroscopic colonic inflammation was more frequent after liver transplantation than before liver transplantation (153 vs 124 patients; P < .001). The degree of inflammation decreased in 37 patients (17%), was unchanged in 93 patients (43%), and increased in 88 patients (40%) (P < .001). The rate of relapse after transplantation was higher than that before transplantation (P < .001), and overall clinical IBD activity also increased (P < .001). Young age at diagnosis of IBD and dual treatment with tacrolimus and mycophenolate mofetil were significant risk factors for increased IBD activity after transplantation, whereas combination treatment with cyclosporin A and azathioprine had protective effects.

CONCLUSIONS

Immunosuppression affects IBD activity after liver transplantation in patients with PSC; a shift from present standard maintenance treatment of tacrolimus and mycophenolate mofetil to cyclosporin A and azathioprine should be considered for these patients.

Systematic review and meta-analysis of randomized trials on probiotics for hepatic encephalopathy

AIM

  The objective of this systematic review and meta-analysis was to assess the efficacy of probiotics and synbiotics in patients with hepatic encephalopathy.

METHODS

  Eligible trials were identified by searching electronic databases including MEDLINE, the Cochrane Library, Science Citation Index and Embase, abstract proceedings, reference lists and ongoing trial registers until 13 October 2010. We included randomized controlled trials comparing probiotics and synbiotics with no intervention, placebo or lactulose in patients with hepatic encephalopathy. The primary outcome measure was improvement in hepatic encephalopathy. RESULTS were expressed as risk rates (RR) with confidence intervals (CI) and intertrial heterogeneity as I(2) .

RESULTS

  Seven trials with a total of 393 patients were analyzed. Compared to placebo or lactulose, treatment with probiotics or synbiotics significantly improved hepatic encephalopathy (RR = 1.40, 95% CI = 1.05-1.86, I(2)  = 5%). Probiotics decreased arterial ammonia (weighted mean difference 15.95; 95% CI = 26.72-3.28; I(2)  = 68%), but not venous ammonia (weighted mean difference 5.23; 95% CI = 21.77-11.30; I(2)  = 89%). Treatment with probiotics or synbiotics did not significantly affect the psychometric tests. Overall adverse events were reported in four trials with no difference between probiotics and placebo groups (RR = 0.32, 95% CI = 0.04-2.57; I(2)  = 59%). Regression analysis showed evidence of small-study effects.

CONCLUSION

  The present meta-analysis suggests that probiotics may be an effective treatment of hepatic encephalopathy, though rigorous evaluation in standardized, randomized, clinical trial with clinically relevant outcomes is still needed.

Colorectal neoplasia in patients with primary sclerosing cholangitis undergoing liver transplantation: a Nordic multicenter study

OBJECTIVE

Several studies have implicated primary sclerosing cholangitis (PSC) as an additional risk factor for colorectal neoplasia in inflammatory bowel disease (IBD). Some reports have indicated that the risk is even higher in PSC-IBD patients after liver transplantation (Ltx), but this issue is controversial. We aimed to compare the risk of colorectal neoplasia in PSC-IBD patients before and after Ltx and to identify risk factors for colorectal neoplasia post-transplant.

MATERIAL AND METHODS

In a multicenter study within the Nordic Liver Transplant Group, we assessed the risk of colorectal neoplasia by using the competing risk regression analysis.

RESULTS

Among the 439 PSC patients included, 353 (80%) had IBD at the time of Ltx and 15 (3%) patients developed de novo IBD post-Ltx. The median duration of IBD was 15 (0-50) years at the time of Ltx and follow-up after Ltx was 5 (0-20) years. Ninety-one (25%) PSC-IBD patients developed colorectal neoplasia. The cumulative risk of colorectal neoplasia was higher after than before Ltx (HR: 1.9, 95% CI: 1.3-2.9, p = 0.002). A multivariate analysis demonstrated aminosalicylates and ursodeoxycholic acid as significantly associated with an increased risk of colorectal neoplasia post-Ltx. Duration and activity of IBD did not significantly affect the risk of neoplasia.

CONCLUSION

The even higher risk of colorectal neoplasia in PSC-IBD patients after when compared with that of before Ltx underscores the importance of regular surveillance colonoscopies post-Ltx. The association of aminosalicylates and ursodeoxycholic acid to the development of colorectal neoplasia after Ltx should be further investigated.

Pathophysiology and clinical implications of peroperative fluid management in elective surgery

The purpose of this thesis was to describe pathophysiological aspects of perioperative fluid administration and create a rational background for future, clinical outcome studies. In laparoscopic cholecystectomy, we have found "liberal" crystalloid administration ( approximately 3 liters) to improve perioperative physiology and clinical outcome, which has implication for fluid management in other laparoscopic procedures such as laparoscopic fundoplication, laparoscopic repair of ventral hernia, hysterectomy etc., where 2-3 liters crystalloid should be administered based on the present evidence. That equal amounts of fluid caused adverse physiologic effects in healthy volunteers indicates that addition of the surgical trauma per se increases fluid requirements. Volume kinetic analysis applied 4 hours postoperatively was not able to detect the presence of either overhydration or hypovolemia regardless of the administered fluid volume intraoperatively. In knee arthroplasty a approximately 4 vs. approximately 2 liters crystalloid-based fluid regimen lead to significant hypercoagulability (although with unknown clinical implications), but no over-all differences in functional recovery. Dehydration caused by bowel preparation leads to functional hypovolemia and the deficits should be corrected, in particular in elderly patients, where preoperative intravenous fluid substitution of approximately 2-3 liters crystalloid is recommended. We did not find thoracic epidural anesthesia to be accompanied by intravascular fluid mobilization. In major (colonic) surgery with a standardized multimodal rehabilitation regimen, over-all functional recovery was not affected with a "liberal" ( approximately 5 liters) vs. "restrictive" 1.5 liter crystalloid-based regimen, however based on three anastomotic leakages in the "restrictive" group, it may be hypothesized that a too "restrictive" fluid administration strategy could be detrimental in patients with anastomoses and need further evaluation. A systematic review concluded that present evidence does not allow final recommendations on which type of fluid to administer in elective surgery. Based on the current evidence, administration of < 5 liters intravenous fluid without specific indication in major surgical procedures should be avoided, while administration of < 1.5 liters in patients with anastomoses may not be recommended, an issue needing clarification in large-scale clinical studies. Finally, we have demonstrated that the conduction of double-blinded randomized trials on fluid management with postoperative outcomes is feasible.

Reconstruction of major bile duct injuries after laparoscopic cholecystectomy

INTRODUCTION

Bile duct injury (BDI) after cholecystectomy remains a serious complication with major implications for patient outcome. For most major BDIs, the recommended method of repair is a hepaticojejunostomy (HJ). We conducted a retrospective review aiming to examine the perioperative and the long-term outcome after reconstructive HJ at our institution.

MATERIAL AND METHODS

Retrospective review of 41 consecutive patients with BDI sustained during cholecystectomy and subsequently managed with a HJ. The patients were referred to a tertiary hepato-biliary centre during a 15-year period (1994-2008).

RESULTS

A total of 32 cases (78%) were reconstructed within two weeks of injury. While 14 patients (34%) suffered perioperative complications, 22 patients (54%) had a complication-free short as well as long-term outcome. Within a median follow-up period of 9.2 years, ten patients (24%) developed biliary strictures requiring percutaneous dilatation and/or further surgery. Three patients had further segmental hepatectomies and one patient developed secondary biliary cirrhosis necessitating orthotopic liver transplantation. No association was found between timing of repair or level of injury and outcome.

CONCLUSION

Early specialist repair may result in acceptable short as well as long-term outcome; however, the morbidity of reconstructive biliary surgery remains high--particularly in the context of patient expectations before laparoscopic cholecystectomy.

[Systemic prokinetic treatment of postoperative ileus following abdominal surgery. Assessment of a Cochrane review]

Based on the evidence presented in the Cochrane review "Systemic prokinetic pharmacologic treatment for postoperative adynamic ileus following abdominal surgery in adults", routine administration of systemic prokinetics for the prevention of postoperative ileus is not recommendable. The potential of selective opioid antagonists and intravenous lidocaine should be further investigated, particularly in conjunction with laparoscopic surgery, epidural pain management and fast-track surgery.

Cyclo-oxygenase 2 inhibitors and the risk of anastomotic leakage after fast-track colonic surgery

BACKGROUND

Anastomotic leakage occurs after 3-6 per cent of colonic resections. The influence of analgesic agents is largely unknown. This study determined the rate of anastomotic leakage in a series of patients who had colonic surgery over a 9-year period with or without use of a cyclo-oxygenase inhibitor for postoperative analgesia.

METHODS

Patients with anastomotic leakage following a standard fast-track procotol between April 1997 and May 2006 were identified from a prospective, consecutive database. During this period there were two changes in perioperative management: cessation of preoperative oral bowel preparation in August 2002 and the use of celecoxib for postoperative analgesia between May 2003 and November 2004. Rates of anastomotic leakage during the various periods were determined and compared.

RESULTS

Some 28 (5.6 per cent) of 502 patients had an anastomotic leak. The incidence of leakage increased significantly during the period of celecoxib use (15.1 per cent), versus 3.3 and 1.5 per cent respectively before and after celecoxib use (P < 0.001). Leakage rates were similar with or without oral bowel preparation (3.5 versus 1.7 per cent respectively; P = 0.346) when celecoxib was not used.

CONCLUSION

A detrimental effect of celecoxib on anastomotic healing is suggested, and requires further evaluation.

[Perioperative fluid therapy in perforated ulcers]

INTRODUCTION

Surgery for perforated ulcers is one of the most common emergency surgical procedures. Approximately 400 procedures are performed each year in Denmark and mortality is high, reaching close to 30% at 30 days postoperatively. The importance of perioperative fluid administration during the perioperative course remains unclear. The purpose of this study is to describe the perioperative fluid management in these patients in order to identify problem areas (if any) and to create a basis on which future trials on fluid management in this patient group may be designed.

MATERIAL AND METHODS

Retrospective survey of 45 consecutive patients operated for perforated ulcers over a 3-year period between 1 January 2003 and 31 December 2005 in the surgical department of a university hospital.

RESULTS

Data that would permit rational fluid therapy are not being collected on a regular basis. Fluid balance charts were kept for 42 patients on the day of operation (89%), for 29 patients on the first post-operative day (61%), for 17 patients on the second post-operative day (36%) and for 12 patients (25%) on the third post-operative day. No patients were weighed for assessment of fluid status. Perioperative fluid administration varied extensively, with fluid balance on the day of surgery ranging from -45 to 8,030 ml (median 2688 ml) and a cumulated fluid balance of 7,2 litres (1,875-14,565 ml) three days postoperatively. Generally, patients had no fluid administered prior to surgery (median 0 ml, applying to 41 patients (87%) range 0-4,500 ml).

CONCLUSION

Both the preoperative fluid management and the postoperative monitoring of the fluid balance are suboptimal and should be optimized. Individualized (goal-directed) fluid administration aiming at optimizing the oxygen supply to the peripheral tissues is warranted and is recommended to high-risk emergency surgery patients.

Intra-operative colloid administration increases the clearance of a post-operative fluid load

BACKGROUND

It is unknown whether an intra-operative colloid infusion alters the dynamics of a crystalloid load administered post-operatively.

METHODS

Ten patients received 12.5 ml/kg of Ringer's lactate over 30 min 1-3 days before and 4 h after laparoscopic cholecystectomy, during which 10 ml/kg of a colloid solution, hydroxyethylstarch (HES 130/0.4), was infused. The total body clearance of the pre- and post-operative test infusions was taken as the ratio between the urinary excretion and the Hb-derived dilution of venous plasma over 150 min. The plasma clearance of the infused fluid was calculated using volume kinetics based on the plasma dilution alone. The pre-operative plasma clearance was compared with the post-operative plasma clearance and patients served as their own control.

RESULTS

The urinary excretion averaged 350 ml for the pre-operative infusion and 612 ml post-operatively, which corresponds to 46% and 68% of the pre- and post-operative infusions, respectively. The total body clearance of the crystalloid fluid was 30 ml/min before surgery and 124 ml/min after surgery (P<0.01). The plasma clearance, as obtained from the plasma dilution alone, was 28 and 412 ml/min, respectively. The maximal increase in plasma volume was 410 ml pre-operatively vs. 220 ml post-operatively.

CONCLUSIONS

Infusion of a colloid solution in combination with a crystalloid during laparoscopic cholecystectomy increased the plasma clearance of a post-operative crystalloid infusion.

[Perioperative fluid therapy--what new?]

Limited evidence on perioperative fluid management has resulted in large variability in administered fluid regimens with unknown implications for the outcome. Present data indicate fluid overload and hypovolemia to be equally deleterious, and individualized fluid therapy may be recommended in high-risk patients undergoing major elective surgery. Future studies should be procedure-specific and with standardized perioperative management with increased focus on the postoperative period.

Liberal or restrictive fluid administration in fast-track colonic surgery: a randomized, double-blind study

BACKGROUND

Evidence-based guidelines on optimal perioperative fluid management have not been established, and recent randomized trials in major abdominal surgery suggest that large amounts of fluid may increase morbidity and hospital stay. However, no information is available on detailed functional outcomes or with fast-track surgery. Therefore, we investigated the effects of two regimens of intraoperative fluids with physiological recovery as the primary outcome measure after fast-track colonic surgery.

METHODS

In a double-blind study, 32 ASA I-III patients undergoing elective colonic surgery were randomized to 'restrictive' (Group 1) or 'liberal' (Group 2) perioperative fluid administration. Fluid algorithms were based on fixed rates of crystalloid infusions and a standardized volume of colloid. Pulmonary function (spirometry) was the primary outcome measure, with secondary outcomes of exercise capacity (submaximal exercise test), orthostatic tolerance, cardiovascular hormonal responses, postoperative ileus (transit of radio-opaque markers), postoperative nocturnal hypoxaemia, and overall recovery within a well-defined multimodal, fast-track recovery programme. Hospital stay and complications were also noted.

RESULTS

'Restrictive' (median 1640 ml, range 935-2250 ml) compared with 'liberal' fluid administration (median 5050 ml, range 3563-8050 ml) led to significant improvement in pulmonary function and postoperative hypoxaemia. In contrast, we found significantly reduced concentrations of cardiovascularly active hormones (renin, aldosterone, and angiotensin II) in Group 2. The number of patients with complications was not significantly different between the groups [1 ('liberal' group) [corrected] vs 6 ('restrictive' group) [corrected] patients, P = 0.08].

CONCLUSIONS

A 'restrictive' [corrected] fluid regimen led to a transient improvement in pulmonary function and postoperative hypoxaemia but no other differences in all-over physiological recovery compared with a 'liberal' [corrected] fluid regimen after fast-track colonic surgery. Since morbidity tended to be increased with the 'restrictive' fluid regimen, future studies should focus on the effect of individualized 'goal-directed' fluid administration strategies rather than fixed fluid amounts on postoperative outcome.

Liberal Versus Restrictive Fluid Management in Knee Arthroplasty: A Randomized, Double-Blind Study

BACKGROUND

There are few data describing the relationship between amount of perioperative fluid and organ function. In this study we investigated the effects of two levels of intravascular fluid administration ("liberal" versus "restrictive") in knee arthroplasty on physiological recovery as the primary outcome variable.

METHODS

In a double-blind study, 48 ASA I-III patients undergoing fast-track elective knee arthroplasty were randomized to restrictive or liberal perioperative intravascular fluid administration. Patients received a fixed rate infusion of Ringer's lactate solution with a standardized volume of colloid. All other aspects of perioperative management (including anesthesia, preoperative fluid status, and postoperative management) were standardized. Primary outcome variables included pulmonary function (spirometry), exercise capacity ("timed up and go" test), coagulation (Thrombelastograph), postoperative hypoxemia (nocturnal pulse oximetry), postoperative ileus (defecation), and subjective patient recovery (visual analog scales). Hospital stay and complications were also noted.

RESULTS

Fluid guidelines were followed strictly in all patients. Liberal (median 4250 mL, range 3150-5200 mL) compared with restrictive (median 1740 mL, range 1100-2165 mL) intravascular fluid administration led to improved pulmonary function 6 h postoperatively, significant hypercoagulability 24-48 h postoperatively, and reduced incidence of vomiting. There were no overall differences in the other assessed perioperative physiological recovery variables (postoperative hypoxemia, exercise capacity or subjective patient recovery variables). No difference was found in hospital stay (median 4 days in both groups, not significant).

CONCLUSION

A liberal compared to a restrictive intravascular fluid regimen may lead to significant hypercoagulability and a reduction in vomiting, but without differences in other recovery variables or hospital stay after fast-track knee arthroplasty.

Monitoring of peri-operative fluid administration by individualized goal-directed therapy

BACKGROUND

In order to avoid peri-operative hypovolaemia or fluid overload, goal-directed therapy with individual maximization of flow-related haemodynamic parameters has been introduced. The objectives of this review are to update research in the area, evaluate the effects on outcome and assess the use of strategies, parameters and monitors for goal-directed therapy.

METHODS

A MEDLINE search (1966 to 2 October 2006) was performed to identify studies in which a goal-directed therapeutic strategy was used to maximize flow-related haemodynamic parameters in surgical patients, as well as studies referenced from these papers. Furthermore, methods applied in these studies and other monitors with a potential for goal-directed therapy are described.

RESULTS

Nine studies were identified pertaining to fluid optimization during the intra- and post-operative period with goal-directed therapy. Seven studies (n = 725) found a reduced hospital stay. Post-operative nausea and vomiting (PONV) and ileus were reduced in three studies and complications were reduced in four studies. Of the monitors that may be applied for goal-directed therapy, only oesophageal Doppler has been tested adequately; however, several other options exist.

CONCLUSION

Goal-directed therapy with the maximization of flow-related haemodynamic variables reduces hospital stay, PONV and complications, and facilitates faster gastrointestinal functional recovery. So far, oesophageal Doppler is recommended, but other monitors are available and call for evaluation.

[Penetrated IUD as the cause of stricture in the sigmoid colon]

A 42-year-old woman became pregnant for the second and third times following insertion of an IUD in the puerperium of her first pregnancy. The IUD was thought to have been expelled. Nineteen years after insertion, the woman developed abdominal pain and diarrhoea. A sigmoid stricture was diagnosed by endoscopy. Laparotomy showed that the IUD had perforated the uterus and penetrated the sigmoid colon. Resection was performed. This case demonstrates the need to investigate every case of a missing IUD.

Influence of “Liberal”versus “Restrictive” Intraoperative Fluid Administration on Elimination of a Postoperative Fluid Load

Background

Previously, the authors found "liberal" fluid administration (approximately 3 l Ringer's lactate [RL]) to improve early rehabilitation after laparoscopic cholecystectomy, suggesting functional hypovolemia to be present in patients receiving "restrictive" fluid administration (approximately 1 l RL). Because volume kinetic analysis after a volume load may distinguish between hypovolemic versus normovolemic states, the authors applied volume kinetic analysis after laparoscopic cholecystectomy to explain the difference in outcome between 3 and 1 l RL.

Methods

In a prospective, nonrandomized trial, the authors studied 20 patients undergoing laparoscopic cholecystectomy. Ten patients received 15 ml/kg RL (group 1) and 10 patients received 40 ml/kg RL (group 2) intraoperatively. All other aspects of perioperative management were standardized. A 12.5-ml/kg RL volume load was infused preoperatively and 4 h postoperatively. The distribution and elimination of the fluid load was estimated using volume kinetic analysis.

Results

Patient baseline demographics and intraoperative data did not differ between groups, except for intraoperative RL, having a median of 1,118 ml (range, 900-1,400 ml) in group 1 compared with a median of 2,960 ml (range, 2,000-3,960 ml) in group 2 (P&lt;0.01). There were no significant preoperative versus postoperative differences in the size of the body fluid space expanded by infused fluid (V), whereas the clearance constant kr was higher postoperatively versus preoperatively (P=0.03). The preoperative versus postoperative changes in volume kinetics including V were not different between the two groups.

Conclusions

Elimination of an intravenous fluid load was increased after laparoscopic cholecystectomy per se but not influenced by the amount of intraoperative fluid administration.

Treatment of anastomotic leakage after rectal resection with transrectal vacuum-assisted drainage (VAC). A method for rapid control of pelvic sepsis and healing

OBJECTIVE

Anastomotic leakage after rectal resection is associated with high morbidity and mortality. Patients without peritonitis can be treated conservatively by transrectal rinsing and drainage. However, healing is often very slow, and formation of abundant scar tissue resulting in a poor functional result is not uncommon. Vacuum-assisted closure (VAC) has been shown to accelerate wound healing by increasing local blood flow, reducing bacterial load and stimulating growth of granulation tissue. In this paper, we describe VAC as a method for treating anastomotic leakage after rectal resection.

METHODS

Four patients with anastomotic leakage after rectal resections were treated with VAC.

RESULTS

Healing time for these patients was median 51 days (43-195). The control group consisted of patients treated conservatively in the previous 5-year period. Ten patients were identified with median healing time 336 days (52-1434).

CONCLUSION

VAC treatment may possibly shorten healing time of anastomotic leakages after rectal resection. However, the presented results are preliminary, with only few patients included, and obviously, larger, randomized, clinical trials are needed to confirm these results and establish the indication for VAC treatment in clinical practice. We believe VAC therapy is a promising treatment of anastomotic leakage after rectal resection.

Liberal versus restrictive fluid administration to improve recovery after laparoscopic cholecystectomy: a randomized, double-blind study

OBJECTIVE

The objective of this study was to investigate the effects of 2 levels of intraoperative fluid administration on perioperative physiology and outcome after laparoscopic cholecystectomy.

SUMMARY BACKGROUND DATA

Intraoperative fluid administration is variable as a result of limited knowledge of physiological and clinical effects of different fluid substitution regimens.

METHODS

In a double-blind study, 48 ASA I-II patients undergoing laparoscopic cholecystectomy were randomized to 15 mL/kg (group 1) or 40 mL/kg (group 2) intraoperative administration of lactated Ringer's solution (LR). All other aspects of perioperative management as well as preoperative fluid status were standardized. Primary outcome parameters were assessed repeatedly for the first 24 postoperative hours and included pulmonary function (spirometry), exercise capacity (submaximal treadmill test), cardiovascular hormonal responses, balance function, pain, nausea and vomiting, recovery, and hospital stay.

RESULTS

Intraoperative administration of 40 mL/kg compared with 15 mL/kg LR led to significant improvements in postoperative pulmonary function and exercise capacity and a reduced stress response (aldosterone, antidiuretic hormone, and angiotensin II). Nausea, general well-being, thirst, dizziness, drowsiness, fatigue, and balance function were also significantly improved, as well as significantly more patients fulfilled discharge criteria and were discharged on the day of surgery with the high-volume fluid substitution.

CONCLUSIONS

Intraoperative administration of 40 mL/kg compared with 15 mL/kg LR improves postoperative organ functions and recovery and shortens hospital stay after laparoscopic cholecystectomy.

Bupivacaine in microcapsules prolongs analgesia after subcutaneous infiltration in humans: a dose-finding study

In this study, we examined the onset and duration of local analgesic effects of bupivacaine incorporated into biodegradable microcapsules (extended-duration local anesthetic; EDLA) administered as subcutaneous infiltrations in different doses in humans. In 18 volunteers, the skin on the medial calf was infiltrated with 10 mL of EDLA, and the opposite calf was infiltrated with 10 mL of aqueous bupivacaine (5.0 mg/mL) in a double-blinded, randomized manner. Three different concentrations of EDLA were tested (6.25, 12.5, and 25 mg/mL), with 6 subjects in each group. Pain responses to mechanical and heat stimuli and sensory thresholds (touch, warm, and cold detection thresholds) were examined by von Frey hairs and contact thermodes. Assessments were made before and 2, 4, 6, 8, 24, 48, 72, 96, and 168 h after the injections. Safety evaluations were performed daily for the first week and at 2 wk, 6 wk, and 6 mo after the injections. The time to maximum effects was significantly shorter for aqueous bupivacaine (2-6 h) than for EDLA (4-24 h), but there were no significant differences between the maximum effects of EDLA and aqueous bupivacaine. From 24 to 96 h after the injections, EDLA was significantly more efficient than aqueous bupivacaine for all variables, and significant effects of EDLA were demonstrated for at least 96 h for all variables. In general, a dose-response gradient was seen in the EDLA group for 5 of 7 variables when the curves expressing effect over time for the different concentrations were evaluated. No serious side effects were observed for up to 6 mo after administration. In conclusion, bupivacaine incorporated in microcapsules provided analgesia for 96 h after subcutaneous infiltration.

Bupivacaine in microcapsules prolongs analgesia after subcutaneous infiltration in humans: a dose-finding study

In this study, we examined the onset and duration of local analgesic effects of bupivacaine incorporated into biodegradable microcapsules (extended-duration local anesthetic; EDLA) administered as subcutaneous infiltrations in different doses in humans. In 18 volunteers, the skin on the medial calf was infiltrated with 10 mL of EDLA, and the opposite calf was infiltrated with 10 mL of aqueous bupivacaine (5.0 mg/mL) in a double-blinded, randomized manner. Three different concentrations of EDLA were tested (6.25, 12.5, and 25 mg/mL), with 6 subjects in each group. Pain responses to mechanical and heat stimuli and sensory thresholds (touch, warm, and cold detection thresholds) were examined by von Frey hairs and contact thermodes. Assessments were made before and 2, 4, 6, 8, 24, 48, 72, 96, and 168 h after the injections. Safety evaluations were performed daily for the first week and at 2 wk, 6 wk, and 6 mo after the injections. The time to maximum effects was significantly shorter for aqueous bupivacaine (2-6 h) than for EDLA (4-24 h), but there were no significant differences between the maximum effects of EDLA and aqueous bupivacaine. From 24 to 96 h after the injections, EDLA was significantly more efficient than aqueous bupivacaine for all variables, and significant effects of EDLA were demonstrated for at least 96 h for all variables. In general, a dose-response gradient was seen in the EDLA group for 5 of 7 variables when the curves expressing effect over time for the different concentrations were evaluated. No serious side effects were observed for up to 6 mo after administration. In conclusion, bupivacaine incorporated in microcapsules provided analgesia for 96 h after subcutaneous infiltration.

Physiologic effects of bowel preparation

PURPOSE

Despite the universal use of bowel preparation before colonoscopy and colorectal surgery, the physiologic effects have not been described in a standardized setting. This study was designed to investigate the physiologic effects of bowel preparation.

METHODS

In a prospective study, 12 healthy volunteers (median age, 63 years) underwent bowel preparation with bisacodyl and sodium phosphate. Fluid and food intake were standardized according to weight, providing adequate calorie and oral fluid intake. Before and after bowel preparation, weight, exercise capacity, orthostatic tolerance, plasma and extracellular volume, balance function, and biochemical parameters were measured.

RESULTS

Bowel preparation led to a significant decrease in exercise capacity (median, 9 percent) and weight (median, 1.2 kg). Plasma osmolality was significantly increased from 287 to 290 mmol kg(-1), as well as increased phosphate and urea concentrations, whereas calcium and potassium concentrations decreased significantly after bowel preparation. No differences in plasma or extracellular volumes were seen. Orthostatic tolerance and balance function did not change after bowel preparation.

CONCLUSIONS

Bowel preparation has significant adverse physiologic effects, which may be attributed to dehydration. The majority of these findings is small and may not be of clinical relevance in otherwise healthy patients undergoing bowel preparation and following recommendations for oral fluid intake.

Development and validation of a brief, descriptive Danish pain questionnaire (BDDPQ)

BACKGROUND

A new pain questionnaire should be simple, be documented to have discriminative function, and be related to previously used questionnaires.

METHODS

Word meaning was validated by using bilingual Danish medical students and asking them to translate words taken from the Danish version of the McGill pain questionnaire into English. Evaluative word value was estimated using a visual analog scale (VAS). Discriminative function was assessed by having patients with one of six painful conditions (postherpetic neuralgia, phantom limb pain, rheumatoid arthritis, ankle fracture, appendicitis, or labor pain) complete the questionnaire.

RESULTS

We were not able to find Danish words that were reliably back-translated to the English words 'splitting' or 'gnawing'. A simple three-word set of evaluative terms had good separation when rated on a VAS scale ('let' 17.5+/-6.5 mm; 'moderat' 42.7+/-8.6 mm; and 'staerk' 74.9+/-9.7 mm). The questionnaire was able to discriminate among the six painful conditions with 77% accuracy by just using the descriptive words. The accuracy of the questionnaire increased to 96% with the addition of evaluative terms (for pain at rest and with activity), chronicity (acute vs. chronic), and location of the pain.

CONCLUSIONS

A Danish pain questionnaire that subjects and patients can self-administer has been developed and validated relative to the words used in the English McGill Pain questionnaire. The discriminative ability of the questionnaire among some common painful conditions has been tested and documented. The questionnaire may be of use in patient care and research.

Epidural anesthesia, hypotension, and changes in intravascular volume

BACKGROUND

The most common side effect of epidural or spinal anesthesia is hypotension with functional hypovolemia prompting fluid infusions or administration of vasopressors. Short-term studies (20 min) in patients undergoing lumbar epidural anesthesia suggest that plasma volume may increase when hypotension is present, which may have implications for the choice of treatment of hypotension. However, no long-term information or measurements of plasma volumes with or without hypotension after epidural anesthesia are available.

METHODS

In 12 healthy volunteers, the authors assessed plasma (125I-albumin) and erythrocyte (51Cr-EDTA) volumes before and 90 min after administration of 10 ml bupivacaine, 0.5%, via a thoracic epidural catheter (T7-T10). After 90 min (t = 90), subjects were randomized to administration of fluid (7 ml/kg hydroxyethyl starch) or a vasopressor (0.2 mg/kg ephedrine), and 40 min later (t = 130), plasma and erythrocyte volumes were measured. At the same time points, mean corpuscular volume and hematocrit were measured. Systolic and diastolic blood pressure, heart rate, and hemoglobin were measured every 5 min throughout the study. Volume kinetic analysis was performed for the volunteers receiving hydroxyethyl starch.

RESULTS

Plasma volume did not change per se after thoracic epidural anesthesia despite a decrease in blood pressure. Plasma volume increased with fluid administration but remained unchanged with vasopressors despite that both treatments had similar hemodynamic effects. Hemoglobin concentrations were not significantly altered by the epidural blockade or ephedrine administration but decreased significantly after hydroxyethyl starch administration. Volume kinetic analysis showed that the infused fluid expanded a rather small volume, approximately 1.5 l. The elimination constant was 56 ml/min.

CONCLUSIONS

Thoracic epidural anesthesia per se does not lead to changes in blood volumes despite a reduction in blood pressure. When fluid is infused, there is a dilution, and the fluid initially seems to be located centrally. Because administration of hydroxyethyl starch and ephedrine has similar hemodynamic effects, the latter may be preferred in patients with cardiopulmonary diseases in which perioperative fluid overload is undesirable.

Effects of posture on postoperative pulmonary function

BACKGROUND

Pulmonary morbidity is still a relevant complication to major surgery despite improvements in surgical technique and anaesthetic methods. Postoperative posture may be a pathogenic factor, but the effects of changes in postoperative posture on pulmonary function have not been reviewed.

METHODS

Review of controlled, clinical trials evaluating postoperative pulmonary function in patients positioned in the supine vs. the sitting or standing position and patients positioned in the supine vs. the lateral position. Data were obtained from a search in the Medline and Cochrane databases (1966 - August 2002) and manually searched bibliographies of the identified papers.

RESULTS

Eighteen papers met the inclusion criteria. Twelve studies evaluated the supine vs. the sitting or standing position and six studies evaluated the supine vs. the lateral position. Six of 12 studies found a positive effect on postoperative pulmonary function in the sitting or standing position compared with the supine. Thus, avoidance of the supine position may improve postoperative pulmonary function. Three of six studies showed a positive effect on postoperative pulmonary function of the lateral side compared with the supine. Thus, the lateral position has limited effects on pulmonary function.

CONCLUSION

Changes of postoperative position from supine to sitting or standing are of major importance in the interpretation of postoperative pulmonary outcome studies and in future strategies to improve pulmonary outcome.

Physiologic effects of intravenous fluid administration in healthy volunteers

Dose regimens in perioperative fluid management are rarely evidence based. Therefore, we investigated responses to an IV fluid infusion in healthy volunteers to assess basic physiologic effects of a fluid infusion per se. In a prospective, double-blinded, cross-randomized study, 12 healthy volunteers with a median age of 63 yr (range, 59-67 yr) received an infusion of lactated Ringer's solution 40 mL/kg (median, 2820 mL) or 5 mL/kg (median, 353 mL; background infusion) in random order on two separate occasions. The study was designed to mimic the perioperative course with preoperative fasting, infusion of the fluid over 3 h in the morning, and additionally 24-h hospitalization under standardized conditions. Primary outcome assessments were pulmonary function (spirometry), exercise capacity (submaximal treadmill test), balance function (BalanceMaster), and weight. Infusion of 40 mL/kg of lactated Ringer's solution compared with the background infusion (5 mL/kg) resulted in a significant decrease in pulmonary function and a significant weight gain of median 0.85 kg (range, -0.2-1.6 kg; P = 0.003) persisting 24 h after the infusion. Exercise capacity and balance function were not influenced by fluid administration. These findings may serve as a basis for clinical studies applying the same type of fluid in different amounts to determine the optimal amount of perioperative fluid in various surgical procedures.

IMPLICATIONS

Infusion of 40 mL/kg of lactated Ringer's solution in volunteers led to a significant decrease in pulmonary function and a significant weight gain for 24 h but without effects on exercise capacity. These findings may serve as basis information for clinical studies of perioperative fluid management.

Postoperative ileus: progress towards effective management

The pathogenesis of postoperative ileus (PI) is multifactorial, and includes activation of inhibitory reflexes, inflammatory mediators and opioids (endogenous and exogenous). Accordingly, various strategies have been employed to prevent PI. As single-modality treatment, continuous postoperative epidural analgesia including local anaesthetics has been most effective in the prevention of PI. Choice of anaesthetic technique has no major impact on PI. Minimally invasive surgery reduces PI, in accordance with the sustained reduction in the inflammatory responses, while the effects of early institution of oral nutrition on PI per se are minor. Several pharmacological agents have been employed to resolve PI (propranolol, dihydroergotamine, neostigmine, erythromycin, cisapride, metoclopramide, cholecystokinin, ceruletide and vasopressin), most with either limited effect or limited applicability because of adverse effects. The development of new peripheral selective opioid antagonists is promising and has been demonstrated to shorten PI significantly. A multi-modal rehabilitation programme including continuous epidural analgesia with local anaesthetics, enforced nutrition and mobilisation may reduce PI to 1-2 days after colonic surgery.

Compensatory fluid administration for preoperative dehydration--does it improve outcome?

BACKGROUND

Preoperative fasting may lead to a fluid deficit of about 1 litre, which may contribute to perioperative discomfort and morbidity. We therefore examined the association between perioperatively administered fluids aiming to correct dehydration and clinical outcome.

METHODS

Review of randomized, controlled, clinical trials evaluating clinical outcome, in which fluid versus no fluid was administered pre- or intraoperatively, attempting to correct preoperative fluid deficits. Data were obtained from a Medline search (1966-2001), and references cited in original papers. Seventeen trials met the inclusion criteria.

RESULTS

Based on the amount of fluid administered, we divided the studies into two groups. In nine studies, fluid administration was <1 litre, and in eight studies > or =1 litre of fluid was administered. Administration of low-dose fluid reduced preoperative thirst, but the limited data do not allow conclusions on postoperative outcome such as nausea, vomiting, headache and pain. Administration of > or =1 litre fluid generally reduced postoperative drowsiness and dizziness, while the effects on postoperative nausea, vomiting and thirst has not been clarified.

CONCLUSION

Fluid administration to compensate preoperative dehydration improves symptoms related to dehydration. Based on the available data, administration of about 1 litre fluid pre- or intraoperatively in patients having fasted for minor surgical procedures seems rational.

Dexamethasone prolongs local analgesia after subcutaneous infiltration of bupivacaine microcapsules in human volunteers

BACKGROUND

The addition of small amounts of dexamethasone to extended-release formulations of bupivacaine in microcapsules has been found to prolong local analgesia in experimental studies, but no clinical data are available.

METHODS

In a double-blinded study, 12 healthy male volunteers were randomized to receive simultaneous subcutaneous injections of bupivacaine microcapsules with dexamethasone and bupivacaine microcapsules without dexamethasone in each calf. Local analgesia was assessed with a validated human pain model; main parameters evaluated were thermal, mechanical, and pain detection thresholds and suprathreshold responses to heat and mechanical stimulation. Measurements were performed every 2 h for the first 8 h and daily for the week after injection. Primary endpoints were evaluation of maximal analgesic effect, time of onset, and duration of analgesia. Summary measures (area under curve [AUC]) were considered best estimate of analgesia. Safety evaluations were performed daily for the first week and at 2 weeks, 6 weeks, and 6 months after injection.

RESULTS

The addition of dexamethasone significantly prolonged local analgesia of bupivacaine microcapsules without influence on maximal analgesic effect. AUC in all thermal measurements and the sensory mechanical threshold were significantly increased between 1-7 days after drug injection in the group given dexamethasone compared with the group not given dexamethasone. No serious side effects were observed.

CONCLUSIONS

Addition of small amounts of dexamethasone to bupivacaine incorporated in microcapsules prolonged local analgesia compared with microcapsules with plain bupivacaine after subcutaneous administration in humans.

Epidural anaesthesia and analgesia - effects on surgical stress responses and implications for postoperative nutrition

BACKGROUND

Surgical injury leads to an endocrine-metabolic and inflammatory response with protein catabolism, increased cardiovascular demands, impaired pulmonary function and paralytic ileus, the most important release mechanisms being afferent neural stimuli and inflammatory mediators.

RESULTS

Epidural local anaesthetic blockade of afferent stimuli reduces endocrine metabolic responses, and improve postoperative catabolism. Furthermore, dynamic pain relief is achieved with improved pulmonary function and a pronounced reduction of postoperative ileus, thereby providing optimal conditions for improved mobilization and oral nutrition, and preservation of body composition and muscle function. Studies integrating continuous epidural local anaesthetics with enforced early nutrition and mobilization uniformly suggest an improved recovery, decreased hospital stay and convalescence.

CONCLUSIONS

Epidural local anaesthetics should be included in a multi-modal rehabilitation programme after major surgical procedures in order to facilitate oral nutrition, improve recovery and reduce morbidity.

Prevention of postoperative ileus

Postoperative ileus (PI) is a major contributor to postoperative morbidity and prolonged convalescence after major surgical procedures. The pathophysiology of PI is multifactorial, including activation of the stress response to surgery, with inhibitory sympathetic visceral reflexes and inflammatory mediators. We update evidence on the advances in the prevention and treatment on PI. As single interventions, continuous thoracic epidural analgesia with local anesthetics and minimally invasive surgery are the most efficient interventions in the reduction of PI. The effects of pharmacological agents have generally been disappointing with the exception of cisapride and the introduction of the new selective peripherally acting m-opioid antagonists. Presently, introduction of a multi-modal rehabilitation programme (including continuous epidural analgesia with local anesthetics, early oral feeding and enforced mobilization) is the most effective technique to reduce PI in abdominal procedures.

Effect of postoperative epidural analgesia on surgical outcome

Pain relief allowing sufficient mobilization after major surgical procedures can only be achieved by continuous epidural analgesia with local anesthetics, which also reduces the stress response to surgery. However, the role of postoperative epidural analgesia on postoperative morbidity is controversial. We therefore update the effects of postoperative analgesia on surgical outcome. After major abdominal surgery, postoperative epidural analgesia with local anesthetics significantly reduces postoperative ileus and pulmonary complications while effects on cardiac morbidity are debatable. Continuous epidural analgesia significantly lowers the risk of thromboembolic complications after lower body procedures, while no effect is seen after major abdominal surgery. Unfortunately, many studies have inadequate study design, with use of lumbar epidural analgesia for abdominal procedures, or the epidural regimen does not contain a sufficient amount of local anesthetics. Future evaluation of the effects of epidural analgesia on postoperative outcome also requires integration of epidural analgesia within a multimodal rehabilitation programme.

Review of postoperative ileus

Postoperative ileus (POI) is an inevitable adverse consequence of surgical procedures. In fact, prolonged POI can lead to patient discomfort, decreased mobility, delayed enteral feeding, and ultimately, prolonged hospitalizations and increased costs. It is believed that POI occurs as a result of inhibitory neural reflexes and inflammatory processes. The use of postoperative opioids also appears to contribute to ileus. Recently, the potential influence of endogenous opioids, in addition to exogenous opioids, on the pathogenesis of ileus has come to light and spurred investigations into new treatment strategies. Over the years, several treatment modalities have become accepted management options for POI; chief among these are nasogastric suction and prokinetic agents. However, data demonstrating that these agents reduce the duration of POI are limited. Of current treatment modalities, use of epidural local anesthetics appears to be the most effective means of reducing POI. Other potentially effective treatments include early enteral feeding and less invasive surgical procedures. Together, these techniques have reduced the length of stay after colonic surgery to 2 to 3 days. Future studies, including those incorporating investigational agents, such as kappa-opioid agonists and peripheral mu-opioid antagonists, into a multimodal regimen, may offer new treatment options to further impact POI duration.

[Gastroesophageal reflux surgery in Denmark 1997-1999]

INTRODUCTION

The incidence and length of postoperative stay in hospital in Denmark after oesophageal reflux surgery has not been described previously.

MATERIAL AND METHODS

We examined the national patient hospital register and discharge information from the hospitals for the number of reflux operations carried out, the length of postoperative hospital stay, readmissions, and postoperative complications occurring within 30 days in the period, 1997-1999.

RESULTS

Twenty-four departments performed 4.9 operations/100,000 inhabitants per year, corresponding to 788 operations. The postoperative 30-day mortality was 0.4% and 6.6% of the operations were followed by serious surgical complications. The combined primary + readmission hospital stay was 3.7 days in the first postoperative month.

DISCUSSION

The small number of oesophageal reflux operations performed in many departments in Denmark is not in agreement with the Danish National Board of Health recommendations from 1996, which say that the operations should be done in only five departments. The spreading of surgery means that only few surgeons can reach sufficient training of surgery and that statistical comparison between the departments of the early results of treatment is not meaningful. Overall, national results are comparable to international results. The incidence of oesophageal reflux surgery is about three times lower than in other Scandinavian countries. On these results, it is recommended that the operation is performed in fewer departments and by fewer surgeons.

Effects of gabapentin in acute inflammatory pain in humans

BACKGROUND AND OBJECTIVES

The aim of the study was to examine the analgesic effects of the anticonvulsant, gabapentin, in a validated model of acute inflammatory pain.

METHODS

Twenty-two volunteers were investigated in a double-blind, randomized, placebo-controlled cross-over study. Gabapentin 1,200 mg or placebo was given on 2 separate study days. Three hours after drug administration, a first-degree burn injury was produced on the medial aspect of the nondominant calf (12.5 cm(2), 47 degrees C for 7 minutes). Quantitative sensory testing (QST) included pain ratings to thermal and mechanical stimuli (visual analog scale [VAS]), assessments of thermal and mechanical detection thresholds, and areas of secondary hyperalgesia. Side effects drowsiness and postural instability were assessed by subjective ratings (VAS).

RESULTS

The burn injury induced significant primary and secondary hyperalgesia (P <.0001). Gabapentin diminished the decrease in mechanical pain threshold in the burn area (P =.04) and reduced secondary hyperalgesia, but the reduction was not significant (P =.06). Heat pain thresholds, pain during the burn, and mechanical pain in the area of secondary hyperalgesia were not significantly changed by gabapentin (P <.2). Ratings of drowsiness and unsteadiness during walking were significantly higher for gabapentin than for placebo (P <.05).

CONCLUSIONS

The study indicates that gabapentin has no analgesic effect in normal skin, but may reduce primary mechanical allodynia in acute inflammation following a thermal injury. These observations suggest a clinical potential of gabapentin in the treatment of postoperative pain.

Epidural analgesia and risk of anastomotic leakage

BACKGROUND AND OBJECTIVES

Based on case reports of early anastomotic leakage in patients receiving epidural analgesia with local anesthetic and data to document a stimulatory effect of epidural block on gastrointestinal motility, it has been suggested that continuous infusion of epidural local anesthetic may lead to an increased incidence of anastomotic leakage. Therefore, we examined the association between continuous epidural local anesthetic and anastomotic leakage by reviewing the literature.

METHODS

Review of controlled, randomized clinical trials aiming to investigate postoperative complications in which continuous postoperative epidural local anesthetic was administered in patients scheduled for colorectal surgery with an anastomosis. Data were obtained from a Medline search (1966-May 2000), previous review articles, references cited in original papers, and personal communication with investigators. Twelve trials including a total of 562 patients met the inclusion criteria.

RESULTS

Sixteen of 266 patients (6.0%, 95% confidence interval [CI]: 3.5% to 9.6%) receiving postoperative epidural local anesthetic or epidural local anesthetic-opioid mixtures developed anastomotic leakage, compared with 10 of 296 patients (3.4%, 95% CI: 1.6% to 6.1%) receiving epidural or systemic opioid-based analgesia (P >.05 between groups, Fisher's test). The risk of overlooking a significant difference (type II error) was approximately 67% (power: 33%). Studies including more than 1,037 patients in each group are needed to demonstrate an increased risk of anastomotic leakage from 3.4% to 6.0% with 80% power and 2alpha = 0.05. There was no significant difference (P >.05 between groups, Fisher's test) between subgroups of study design: Epidural local anesthetic-versus systemic or epidural opioid, or epidural local anesthetic-opioid mixtures versus systemic or epidural opioid.

CONCLUSIONS

So far, there is no statistically significant evidence from randomized trials to indicate epidural analgesia with local anesthetic to be associated with an increased risk of anastomotic breakdown. However, relatively few patients have been included in randomized trials, indicating a need for more studies to secure valid conclusions.

[How to teach ballet to a swat?]

There is increasing interest in including humanities subjects in the medical curriculum, as a means of accelerating students' personal development and of helping them in their meeting with patients, in order to counteract a perceived communication deficit in the health care system. Traditionally, medical schools have favoured students who concentrate on what is most relevant for their exams, possibly at the expense of reflection, idealism and empathy. As medical students in the University of Oslo, we do not feel that the situation is as bad as some claim it is. Most medical students have a wide range of ability and show interest and involvement in their own as well as their patients' situation. Humanities subjects are included in the curriculum, but it is tempting to see them as "spice" added for flavour and spread out over the course with no clear logic behind it. We do not necessarily see the need for more humanities courses, but we do see a need for more critical evaluation of what is taught. Humanities in the medical education should aim not just at improving communication skills, they should also include perspectives on how health care professionals can take of themselves, and put medicine into a wider scientific and historical perspective.

Postoperative ileus: a preventable event

BACKGROUND

Postoperative ileus has traditionally been accepted as a normal response to tissue injury. No data support any beneficial effect of ileus and indeed it may contribute to delayed recovery and prolonged hospital stay. Efforts should, therefore, be made to reduce such ileus.

METHODS

Material was identified from a Medline search of the literature, previous review articles and references cited in original papers. This paper updates knowledge on the pathophysiology and treatment of postoperative ileus.

RESULTS AND CONCLUSION

Pathogenesis mainly involves inhibitory neural reflexes and inflammatory mediators released from the site of injury. The most effective method of reducing ileus is thoracic epidural blockade with local anaesthetic. Opioid-sparing analgesic techniques and non-steroidal anti-inflammatory agents also reduce ileus, as does laparoscopic surgery. Of the prokinetic agents only cisapride is proven beneficial; the effect of early enteral feeding remains unclear. However, postoperative ileus may be greatly reduced when all of the above are combined in a multimodal rehabilitation strategy.

Newly administered [3H]retinol is transferred from hepatocytes to stellate cells in liver for storage

We have recently shown that newly administered vitamin A (retinol) is initially taken up by the parenchymal cells of the liver, and subsequently (within 1-2 h) transferred to non-parenchymal liver cells (NPC) (Blomhoff et al., ref. [10]). In the present study we have separated the NPC by different methods to determine the cell type responsible for this uptake of [3H]retinol. When liver cells were prepared between 5 and 18 h after intraduodenal administration of [3H]retinol, the radioactive retinol was recovered mainly in the stellate cells. Other liver cells (i.e., hepatocytes, endothelial cells and Kupffer cells) contained only small amounts of [3H]retinol. Further, fluorescence microscopy studies indicated that stellate cells contain large quantities of retinol. Our results show that newly administered [3H]retinol, which is initially located in the hepatocytes, is transferred to the stellate cells and stored there.

Effects of local anesthetics and related compounds on the endocytosis and catabolism of asialo-glycoproteins in isolated hepatocytes

The effects of local anesthetics, including procaine and dibucaine, and some related amine compounds, such as dansyl-cadaverine, were studied with respect to their effects on the uptake and degradation of asialo-glycoproteins in isolated hepatocytes. 0.5 mM of either dibucaine or dansyl-cadaverine reduced the rates of uptake to 18-19% of control value; other amines were less effective. Dibucaine and dansyl-cadaverine both acted by reducing the surface binding capacity of the cells as well as by reducing the rate of internalization of surface-bound asialo-glycoprotein. All of the compounds that affected the uptake, including dansyl-cadaverine, also reduced the rate of degradation. This effect could be studied separately from their effect on uptake. The concentrations that were required in order to reduce degradation were, in general 0.5-0.25 of those which caused a reduction in the uptake. Even though dibucaine, lidocaine and dansyl-cadaverine were found to accumulate in the lysosomes, it was concluded from studies with isopycnic centrifugation in sucrose gradients that all three compounds inhibited the rate of transfer of endocytosed protein from endocytic vesicles to lysosomes. This effect could be due to a reduced rate of fusion between endocytic vesicles and lysosomes.

Quantitative study of the uptake of IgA by isolated rat hepatocytes

Recently dispersed rat hepatocytes showed high capacity for uptake of monomeric and polymeric human IgA by simple absorptive endocytosis. Maximum uptake exceeded 15 million monomer units per cell. The asialo-glycoprotein receptor was not involved in this process. J chain-containing polymers were on the average taken up somewhat better than monomers and substantially better than J chain-deficient polymers. This result would agree with a partial involvement of the secretory component (SC) in the absorptive uptake of IgA. Different receptor mechanism might hence explain the hepatic transport of IgA from blood to bile in the rat and perhaps be involved in the catabolism of IgA. After binding to the plasma membrane of the rat hepatocyte, most of the human IgA was internalized in endocytic vesicles. A considerable proportion of radiolabelled IgA apparently reached the lysosomes after internalization and became degraded.