The effect of spinal anesthesia that is performed in sitting or right lateral position on post-spinal headache and intraocular pressure during elective cesarean section

Background

Although spinal anesthesia can be applied in different patient positions, the most frequently used positions are sitting and lateral positions. It is known that different patient positions during spinal anesthesia have effects on hemodynamic parameters, postdural puncture headache, and intraocular pressure.

Aim

The study aimed to determine the effect of spinal anesthesia performed in either sitting or right lateral position on postspinal headache and intraocular pressure during elective cesarean section.

Patients and Methods

The study was a randomized controlled study of 104 eligible pregnant women scheduled to undergo elective cesarean section. The women were randomized into two groups. Spinal anesthesia was performed either in the sitting (Group S, n = 53) or the right lateral position (Group L, n = 51). Heart rate and blood pressure were recorded throughout the operation. The participants were informed and monitored for postspinal headaches. Intraocular pressure before and after the operation was measured with Icare PRO. The obtained data were statistically compared between the two groups.

Results

There was no difference between the groups in terms of demographic data. Postdural puncture headache was observed in five patients in Group S and one patient in Group L (P =0.04). There was no difference between the groups in terms of intraocular pressure (P >.05). Heart rate was not significantly different between the groups; however, there was a significant difference in average blood pressure in 1, 5, 30, and 40 minutes (P <.05). The number of trials administered to patients for spinal anesthesia was significantly higher in Group L (P =0.01).

Conclusion

Spinal anesthesia performed in the sitting position for cesarean section caused a higher postspinal headache than in the right lateral position, but the position did not affect intraocular pressure.

AB0495 SERUM AND URINE GALECTIN-9, IP-10 AND SIGLEC-1 AS BIOMARKERS OF DISEASE ACTIVITY IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS

Background

Galectin-9, interferon-inducible protein-10 (IP-10) and sialoadhesin (SIGLEC-1) are proteins associated with interferon signature, and considered as potential biomarkers reflecting disease activity in patients with systemic lupus erythematosus (SLE).

Objectives

In this study, we aimed to investigate the association of serum and urine levels of galectin-9, IP-10 and SIGLEC-1 with disease activity in patients with SLE.

Methods

Sixty-three patients with active SLE (31 renal and 32 extrarenal) were included in the study. Thirty inactive patients with SLE (15 renal and 15 extrarenal) and 32 healthy volunteers were selected as control groups. Serum (s) and urine (u) levels of galectin-9, IP-10 and SIGLEC-1 were tested using ELISA. Urine levels of biomarkers were normalized by urine creatinine.

Results

Groups were comparable with regard to sex and age distribution. Of 125 participants, 102 (81.6%) were female and median age was 33 (28-44.5) years. Proliferative lupus nephritis (LN) (class III/III+V and IV/IV+V) were found in 22 patients with active renal SLE (70.9%), while 6 patients (19.3%) had pure class V and 3 (9.7%) had class II LN. Levels of sIP-10, uIP-10, sGalectin-9 and uSIGLEC-1 were significantly higher in the active SLE group compared to the inactive SLE group (sIP-10 p=0.046, uIP-10 p<0.001, sGalectin-9 p=0.031 and uSIGLEC-1 p=0.006); however, no differences were detected in the comparison of uGalectin-9 and sSIGLEC-1 between the groups (uGalectin-9 p=0.180 and sSIGLEC-1 p=0.699) (Table 1). Serum and urine levels of galectin-9, IP-10 and SIGLEC-1 did not differ between patients with active renal and extrarenal SLE. Levels of sIP-10, uIP-10 and uSIGLEC-1 were correlated with SLE Disease Activity Index (SLEDAI). Serum and urine levels of all biomarkers were re-tested in 41 of 63 patients (65%) with active SLE after a median treatment of 8 (5-22.5) months. At the time of the second tests, there was a significant decrease in disease activity as measured by SLEDAI [2 (0-4)] compared to the time of the first tests [10 (6-15.5)]. Comparison of sGalectin-9 levels between the serum at the time of active disease and remission showed a very significant decline (p<0.001) as shown in Figure 1. uGalectin-9, sIP-10 and uSIGLEC-1 also decreased after treatment; however, the difference was not statistically significant.

Table 1.

Serum and urine levels of biomarkers across study groups.

BiomarkerActive SLE(n=63)Inactive SLE(n=30)Healthy Control(n=32)sGalectin-9 (ng/ml)11.73 (7.52-14.15)8.66 (7.51-10.02)5.61 (4.56-6.6)sIP-10 (pg/ml)279.4 (147.5-430.3)173.4 (142.2-247.9)74.3 (58.8-103)sSIGLEC-1 (pg/ml)181.2 (157.8-213.9)182.5 (169.9-203.1)258.3 (179-602)uGalectin-9 (ng/ml)8.83 (4.07-18.11)11.54 (7.03-15.07)10.63 (5.55-17.4)uIP-10 (pg/ml)34.4 (15.9-73,9)20.8 (9.9-53.3)12.2 (1.8-25.7)uSIGLEC-1 (pg/ml)321 (236.3-370.9)297.6 (247.7-371)290 (205.1-323.5)uGalectin-9 (ng/mgCre)15.50 (9.60-32.05)11.41 (8.78-19.54)13.57 (11.27-22.08)uIP-10 (pg/mgCre)73.4 (40.9-136.9)26.1 (18.1-55.1)16.4 (5-32.5)uSIGLEC-1 (pg/mgCre)619.6 (389.4-1056.5)393.2 (248.6-715.8)425.6 (264.7-925.9)Figure 1.

Serum levels of galectin-9 before and after the treatment in 41 patients with active SLE.

Conclusion

sIP-10, uIP-10, sGalectin-9 and uSIGLEC-1 are associated with disease activity in SLE. None is able to discriminate active renal from active extrarenal disease. sGalectin-9 may be a valuable biomarker to monitor response after treatment for active disease (Funded by Scientific Research Projects Coordination Unit of Istanbul University. Project number: TSA-2019-34218).

Disclosure of Interests

None declared

POS0766 CLUSTER ANALYSIS AND COMPARISON OF CUMULATIVE DAMAGE BY DIAPS IN A SINGLE CENTER COHORT OF APS PATIENTS

Background:

Antiphospholipid syndrome (APS) is a chronic autoimmune disease with significant morbidity and mortality. The recently developed damage index for APS (DIAPS) considers thrombotic APS specific damage.

Objectives:

Herein we aimed to identify disease clusters based on clinical characteristics and compare DIAPS between these clusters in a single center cohort of patients with APS ± systemic lupus erythematosus (SLE).

Methods:

This retrospective study included 237 consecutive patients with APS [114 primary APS (PAPS) and 123 SLE+APS]. Data regarding demographics, clinical and laboratory characteristics and cardiovascular risk factors were retrieved from the existing database and revised. Two-step cluster analysis was performed. Cumulative damage was calculated for all patients by applying DIAPS as described previously.

Results:

237 patients were classified into 4 subgroups by cluster analysis. Cluster 1 (n=74) consisted of older patients with arterial-predominant VT, livedo reticularis and increased cardiovascular risk, cluster 2 (n=70) of SLE+APS patients with thrombocytopenia and heart valve disease, cluster 3 (n=59) of patients with venous-predominant VT, less extra-criteria manifestations and cluster 4 (n=34) of patients with only PM with a lower frequency of extra-criteria features and cardiovascular risk (table 1).

Table 1.

Demographic, clinical and laboratory characteristics of clusters

All (n=237)Cluster 1 (n=74)Cluster 2 (n=70)Cluster 3(n=59)Cluster 4 (n=34)PAge (years), median (range)43 (20-81)51 (20-81)40 (27-72)42 (24-69)40.5 (26-65)<0.001Duration of disease (years), median (range)9.5 (1-37.7)13.1 (1-37.7)10.4 (1-28.7)8.5 (1-32.8)7 (1-22.4)0.028Female, n (%)198 (83.5)56 (75.7)61 (87.1)47 (79.7)34 (100)<0.05SLE, n (%)123 (51.9)31 (41.9)46 (65.7)32 (54.2)14 (41.2)<0.05Vascular thrombosis, n (%)191 (80.6)73 (98.6)59 (84.3)59 (100)0 (0)<0.001Arterial thrombosis, n (%)109 (46)50 (67.6)31 (44.3)28 (47.5)0 (0)<0.001Venous thrombosis, n (%)112 (47.3)36 (48.6)37 (52.9)39 (66.1)0 (0)<0.001Pregnancy morbidity, n (%)117 (49.4)22 (29.7)46 (65.7)15 (25.4)34 (100)<0.001Livedo reticularis, n (%)38 (16)21 (28.4)10 (14.3)5 (8.5)2 (5.9)<0.01Thrombocytopenia, n (%)81 (34.2)4 (5.4)65 (92.9)4 (6.8)8 (23.5)<0.001Heart valve disease, n (%)92 (38.8)32 (43.2)46 (65.7)8 (13.6)6 (17.6)<0.001Arterial hypertension, n (%)101 (42.6)49 (66.2)34 (48.6)18 (30.5)0 (0)<0.001Hyperlipidemia, n (%)103 (43.5)69 (93.2)26 (37.1)0 (0)8 (23.5)<0.001Smoking, n (%)58 (24.5)31 (41.9)7 (10)17 (28.8)3 (8.8)<0.001Lupus anticoagulant, n (%)156 (65.8)53 (71.6)48 (68.6)35 (59.3)20 (58.8)0.36Anticardiolipin IgG/IgM, n (%)155 (65.4)46 (62.2)46 (65.7)38 (64.4)25 (73.5)0.71Anti-β2-glycoprotein I IgG/IgM, n (%)93 (39.2)25 (33.8)33 (47.1)26 (44.1)9 (26.5)0.13Triple aPL positivity, n (%)45 (19)12 (16.2)16 (22.9)13 (22)4 (11.8)0.46

Cluster 2 had the highest cumulative damage (mean DIAPS 2.48 ± 1.67) followed by cluster 1 (2.24 ± 1.44), cluster 3 (1.69 ± 1.27) and cluster 4 (0.32 ± 0.68). Comparison of DIAPS (total and major domains) between the clusters is shown in figure 1.

Patients with SLE+APS had a higher mean DIAPS compared to those with PAPS (2.10 ± 1.61 vs 1.69 ± 1.47, P=0.046). Cardiovascular domain was the most frequently affected DIAPS domain in both groups. Proteinuria and avascular necrosis were significantly more frequent in SLE+APS (9.8% vs 2.2%, P=0.02 and 5.7% vs 0%, P=0.009, respectively). DIAPS was positively correlated with disease duration (r=0.192, P=0.003).

Conclusion:

Elder APS patients with arterial thrombosis and increased cardiovascular risk and SLE+APS patients with extra-criteria manifestations had higher cumulative DIAPS. Longer disease duration, higher frequency of major organ involvement and higher immunosuppressive usage may have contributed to this difference. Therefore, control of cardiovascular risk factors, prevention and effective treatment of SLE flares may help to reduce damage in these subgroups.

Figure 1.

Comparison of mean DIAPS (total and major domains) between the clusters

Disclosure of Interests:

None declared

SAT0238 VALIDATION OF THE ADJUSTED GLOBAL ANTIPHOSPHOLIPID SYNDROME SCORE AND CORRELATION WITH EXTRA-CRITERIA MANIFESTATIONS

Background:

Adjusted global antiphosholipid syndrome score (aGAPSS) is the simplified version GAPSS that was recently developed to assess thrombotic risk by the consideration of antiphospholipid antibody (aPL) profile and conventional cardiovascular risk factors.

Objectives:

The aim of this study was to evaluate the validity of the aGAPSS in predicting thrombosis and extra-criteria manifestations in our antiphospholipid syndrome (APS) cohort.

Methods:

Ninety-eight patients with APS were classified according to clinical manifestations as vascular thrombosis (VT), pregnancy morbidity (PM) or both (VT+PM). The aGAPSS was calculated as defined before. Arterial hypertension and hyperlipidemia definitions were made according to the ESC/ESH ve NCEP/ATP III guidelines, respectively.

Results:

Demographic, laboratory and clinical characteristics of patients are summarized in table-1. Mean aGAPSS was calculated as 10.2 ± 3.8. Significantly higher aGAPSS values were seen in VT (n=58) and VT+PM (n=29) compared to PM (n=11) (mean aGAPSS 10.6 ± 3.7 vs 7.3 ± 2.9, P=0.005; 10.5 ± 4 vs 7.3 ± 2.9, P=0.01, respectively). AUC demonstrated that aGAPSS values ≥ 10 had the best diagnostic accuracy for thrombosis (figure-1). Higher aGAPPS values were also associated with recurrent thrombosis (mean aGAPSS 11.5 ± 3.7 vs 9.9 ± 3.6, P=0.04). Regarding extra-criteria manifestations, patients with livedo reticularis (n=11) and APS nephropathy (n=9) had significantly higher aGAPSS values (mean aGAPSS 12.9 ± 3.4 vs 9.9 ± 3.7, P=0.02; 12.4 ± 2.9 vs 10 ± 3.8, P=0.04, respectively).

Conclusion:

Our results suggest that patients with higher aGAPSS values are at higher risk for developing vascular thrombosis (either single or recurrent) and extra-criteria manifestations, especially livedo reticularis and APS nephropathy.

Table-1.

Demographic, laboratory and clinical characteristics of patients.

PAPS (n=42)n(%)SLE/APS (n=56)n(%)PFemale36 (85.7)47 (83.9)0.52Age, years (mean±SD)44.6 (11.6)40.8 (10.1)0.42Disease duration, years (mean±SD)10 (8.8)9.7 (7.1)0.16Thrombosis35 (83.3)52 (92.9)0.12•Arterial24 (68.6)34 (65.4)0.47•Venous19 (54.3)26 (50)0.43•Recurrent15 (42.9)22 (42.3)0.56Pregnancy morbidity20 (47.6)20 (35.7)0.16•<10 weeks, ≥ 3 abortions5 (25)4 (20)0.5•≥ 10 weeks, ≥ 1 abortion14 (70)15 (75)0.5•Pre-eclampsia/eclampsia3 (15)5 (25)0.34•<34 weeks, ≥ 1 premature birth1 (5)5 (25)0.09Convensional risk factors•Arterial hypertension17 (40.5)35 (62.5)0.02•Hyperlipidemia21 (50)26 (46.4)0.41•Diabetes mellitus3 (7.1)3 (5.4)0.51•Obesity19 (45.2)16 (28.6)0.07•Smoking12 (28.6)18 (32.1)0.43aPL profile•LA29 (69)48 (85.7)0.04•aCL IgG/IgM31 (73.8)28 (52.8)0.03•aβ2GPI IgG/IgM22 (56.4)27 (52.9)0.45•Triple positive14 (33.3)17 (30.4)0.46Figure 1.

ROC curve according to cut-off aGAPSS value: 10 (AUC: 0.71, sensitivity: 0.52, specificity: 0.91, positive predictive value: 0.98, negative predictive value: 0.19, p-value: 0.01).

Disclosure of Interests:

None declared

Is a morphologically intact anal sphincter necessary for success with sacral nerve modulation in patients with faecal incontinence?

OBJECTIVE

Sacral nerve modulation (SNM) for the treatment of faecal incontinence was originally performed in patients with an intact anal sphincter or after repair of a sphincter defect. There is evidence that SNM can be performed in patients with faecal incontinence and an anal sphincter defect.

METHOD

Two groups of patients were analysed retrospectively to determine whether SNM is as effective in patients with faecal incontinence associated with an anal sphincter defect as in those with a morphologically intact anal sphincter following anal repair (AR). Patients in group A had had an AR resulting in an intact anal sphincter ring. Group B included patients with a sphincter defect which was not primarily repaired. Both groups underwent SNM. All patients had undergone a test stimulation percutaneous nerve evaluation (PNE) followed by a subchronic test over 3 weeks. If the PNE was successful, a permanent SNM electrode was implanted. Follow-up visits for the successfully permanent implanted patients were scheduled at 1, 3, 6 and 12 months and annually thereafter.

RESULTS

Group A consisted of 20 (19 women) patients. Eighteen (90%) had a positive subchronic test stimulation. Twelve patients had a successful SNM implant during middle-term follow-up. Group B consisted of 20 women. The size of the defect in the anal sphincter varied between 17% and 33% of the anal circumference. Fourteen (70%) had a positive subchronic test stimulation. Twelve patients had a successful SNM implant during middle-term follow-up. In both groups, the mean number of incontinence episodes decreased significantly with SNM (test vs baseline: P = 0.0001, P = 0.0002). There was no significant difference in resting and squeeze pressures during SNM in group A, but in group B squeeze pressure had increased significantly at 24 months. Comparison of patient characteristics and outcome between groups A and B revealed no statistical differences.

CONCLUSION

A morphologically intact anal sphincter is not a prerequisite for success in the treatment of faecal incontinence with SNM. An anal sphincter defect of <33% of the circumference can be effectively treated primarily with SNM without repair.

Sacral neuromodulation in patients with faecal incontinence: results of the first 100 permanent implantations

OBJECTIVE

Faecal incontinence (FI) is a socially devastating problem. Sacral nerve modulation (SNM) has proven its place in the treatment of patients with FI. In this study, the first 100 definitive SNM implants in a single centre have been evaluated prospectively.

METHOD

Patients treated between March 2000 and May 2005 were included. Faecal incontinence was defined as at least one episode of involuntary faecal loss per week confirmed by a 3-week bowel habit diary. Patients were eligible for implantation of a permanent SNM when showing at least a 50% reduction in incontinence episodes or days during ambulatory test stimulation. Preoperative workup consisted of an X-defaecography, pudendal nerve terminal motor latency measurement, endo-anal ultrasound and anal manometry. The follow-up visits for the permanent implanted patients were scheduled at 1, 3, 6 and 12 months and annually thereafter. The bowel habit diary and anal manometry were repeated postoperatively during the follow-up visits.

RESULTS

A total of 134 patients were included and received a subchronic test stimulation. One hundred patients (74.6%) had a positive test stimulation and received a definitive SNM implantation. The permanent implantation group consisted of 89 women and 11 men. The mean age was 55 years (range 26-75). The mean follow-up was 25.5 months (range 2.5-63.2). The mean number of incontinence episodes decreased significantly during the test stimulation (baseline, 31.3; test, 4.4; P < 0.0001) and at follow-up (36 months postoperatively, 4.8; P < 0.0001). There was no significant change in the mean anal resting pressure. The squeeze pressures were significantly higher at 6 months (109.8 mmHg; P = 0.03), 12 months (114.1 mmHg; P = 0.02) and 24 months postoperatively (113.5 mmHg; P = 0.007). The first sensation, urge and maximum tolerable volume did not change significantly. Twenty-one patients were considered late failures and received further treatment.

CONCLUSION

Sacral neuromodulation is an effective treatment for FI. The medium-term results were satisfying.

Sacral neuromodulation; does it affect colonic transit time in patients with faecal incontinence?

OBJECTIVE

Sacral neuromodulation (SNM) has been a successful treatment in urinary voiding disorders for years. A concomitant effect on bowel function was observed leading to the treatment of faecal incontinence with SNM. In this study we describe the effect of SNM on bowel frequency and (segmental) colonic transit time.

PATIENTS AND METHODS

Fourteen patients with faecal incontinence who qualified for permanent SNM underwent a colon transit study before and one month after permanent implant. Patients completed a three-week bowel habits diary before and during stimulation.

RESULTS

Median incontinence episodes and days per week before SNM were, 8.7 and 4.2, respectively, and both decreased significantly to 0.67 (P = 0001) and 0.5 (P = 0001) during trial screening and to 0.33 (P = 0001) and 0.33 (P = 0001) after permanent implant. The median number of bowel movements per week decreased from 14.7 (6.7-41.7) to 10.0 (3.7-22.7)(P = 0005) during trial screening and to 10.0 (6.0-24.3)(P = 0008) during permanent stimulation. Resting and squeeze pressures did not change significantly during stimulation. Segmental colonic transit time before and during stimulation for right colon, left colon and recto sigmoid were, respectively, 6 (0-25) vs 5 (0-16) hours, 2 (0-29) vs 4 (0-45) hours and 7 (28) vs 8 (0-23) hours. No significant changes were found in both segmental and total colonic transit time; 17 (1-65) vs 25 (0-67) hours.

CONCLUSION

SNM in patients with fecal incontinence led to a significant decrease of bowel movements however (segmental) colonic transit time was not influenced.

Effect of sacral neuromodulation on the rectum

Background

Sacral neuromodulation (SNM) is a new treatment for faecal incontinence. At present the exact underlying mechanism is still unclear. Modulation of the sacral reflex arcs might have an effect on rectal sensitivity, wall tension and compliance.

Methods

Fifteen consecutive patients with faecal incontinence who qualified for SNM underwent barostat measurements before and during neuromodulation. An ‘infinitely’ compliant plastic bag with a volume of 600 ml was placed in the rectum and connected to a computer-controlled barostat system. An isobaric phasic distension protocol was used. Patients were asked to report rectal filling sensations: first sensation (FS), earliest urge to defaecate (EUD) and an irresistible, painful urge to defaecate (maximum tolerated volume; MTV). Rectal wall tension and compliance were calculated.

Results

During isobaric phasic distension each patient experienced all rectal filling sensations at the time of stimulation. Median volume thresholds decreased significantly during stimulation, from 98·1 to 44·2 ml for FS (P = 0·003), from 132·3 to 82·8 ml for EUD (P = 0·001) and from 205·8 to 162·8 ml for MTV (P = 0·002). Pressure thresholds tended to be lower for all filling sensations, but only that to evoke MTV was reduced significantly by stimulation (37·3 versus 30·3 mmHg; P = 0·005). Median rectal wall tension for all filling sensations decreased significantly with stimulation. There was no significant difference between compliance before and during stimulation.

Conclusion

SNM affects rectal sensory perception, but further research is required to clarify the mechanism.

Second-line treatment for faecal incontinence

BACKGROUND

In the treatment of faecal incontinence, more than 30% of patients experience continuation of their problem. We discuss new therapeutic procedures for dealing with faecal incontinence.

METHODS

Discussion of authors' own work in relation to the literature.

RESULTS

First-line care includes diets, constipating drugs, biofeedback therapy, anal repair and operations for prolapse and fistulas. For the failures of these first-line treatments there is hope with second-line therapies. Creation of a neosphincter is possible with a dynamic graciloplasty (DGP) or an artificial bowel sphincter (ABS). A DGP is a conventional graciloplasty with the addition of implanted electrodes and a stimulator that transforms the muscle into an automatic contracting sphincter. ABS comprises an inflatable cuff around the anus that is filled from a pressure-regulating balloon. The cuff can be emptied with an implanted pump.

CONCLUSIONS

DGP and ABS give good results in 56%-88% of cases. For patients with an anatomical intact but nonfunctioning sphincter there is a new treatment: sacral nerve stimulation. This gives continence in a high percentage of cases, but experience is rather limited. Second-line treatment for faecal incontinence is successful and should be considered in cases where initial therapies fail.

Incidence of surgical site infections in pediatric patients: a 3-month prospective study in an academic pediatric surgical unit

During a 3-month period 259 pediatric surgical procedures in 236 patients were followed for the development of surgical site infections (SSI): 17 sites became infected, an overall infection rate of 6.6%. The incidence in our study was therefore higher than expected. As expected, the infection rate increased according to wound contamination: dirty sites had a SSI rate of 30%. Emergency procedures, operation duration over 1 h, and inpatients showed a statistically significant higher risk of developing SSI. Although there were differences between males and females, individual surgeons, and the use of antibiotic prophylaxis, these differences were not statistically significant.

Effects of nitric oxide synthase inhibition in lipopolysaccharide-induced sepsis in mice

In the present study, we have investigated the effects of nitric oxide (NO) synthase inhibition on mortality in lipopolysaccharide (LPS)-induced sepsis in mice. Serum nitrite levels peaked at 15 h after an injection of LPS (10 mg kg-1, i.p.). Aminoguanidine, a selective inducible NO synthase (iNOS) inhibitor, at a dose of 100 mg kg-1 significantly reduced the LPS-induced increase in nitrite levels and improved mortality. Econazole, iNOS inhibitor, calmodulin antagonist, 5-lipoxygenase and a specific thromboxane synthase inhibitor, at a 1 mg kg-1 dose significantly decreased the LPS-induced increase in nitrite levels, but increased mortality 4. 9-fold when compared to the LPS group (control). Indomethacin, a putative iNOS and non-selective cyclo-oxygenase (COX) inhibitor, of 1, 10 and 100 mg kg-1, dose dependently decreased the LPS-induced increase in nitrite levels. This decrease was significantly different from the control at 10 and 100 mg kg-1 dose levels. When indomethacin (100 mg kg-1) was combined with aminoguanidine (100 mg kg-1), LPS-induced nitrite levels were significantly attenuated. NO precursor, L-arginine, was added to this combination in order to test the inhibition of iNOS activity which resulted in no change in nitrite levels. An indomethacin and aminoguanidine combination increased mortality twofold when compared to the control. The addition of L-arginine to the combination enhanced the mortality rate to 1.5-fold. These results suggest that NO appears to play a role in the LPS-induced septic shock model in mice. The improvement in sepsis-induced mortality enhanced by aminoguanidine by the inhibition of iNOS but not with the other agents or combinations should be re-evaluated in order to make an appropriate choice of the therapeutic target. In addition, it may also suggest that other mediators, such as arachidonic acid products and cytokines play a role in septic shock pathogenesis as well. (c) 1998 The Italian Pharmacological Society.