Review of postoperative CT and ultrasound for endovascular aneurysm repair using Talent stent graft: can we simplify the surveillance protocol and reduce the number of CT scans?

BACKGROUND

Simplifying a postoperative surveillance protocol for endovascular aneurysm repair (EVAR) requires quality control comparing computerized tomography (CT) and ultrasound (US) results of abdominal aortic aneurysm (AAA) diameter measurements and endoleaks.

PURPOSE

To test if US is comparable to CT, then assess a simplified follow-up with our conventional surveillance to assess patient safety.

MATERIAL AND METHODS

During 2001-2006, data on 56 patients treated with Talent stent graft were prospectively registered. Median follow-up was 41.5 months (range, 2-94 months), with CT, US, and plain film abdomen X-rays (PFA) at 1, 6, and 12 months, then yearly. Bland-Altman plot was used to assess the agreement between CT and US measuring the AAA diameters and mixed model by the time effect to assess the difference in diameter over time. Sensitivity and specificity for detection of endoleaks by US, with CT as 'gold standard' were calculated. A simplified surveillance protocol with US/PFA at 6 and 8 weeks, CT/US/PFA at 1 year, and yearly US/PFA thereafter, was evaluated. CT was carried out when poor visibility, endoleak detected, AAA diameter increase (≥5 mm) on US or migration (≥10 mm) on PFA. This regime was compared with our conventional follow-up protocol.

RESULTS

Diameter measurements on US appear comparable to CT with 91% specificity and 85% sensitivity for endoleaks detected by US. Using the simplified surveillance protocol no endoleaks, migrations, or endotension requiring treatment were overlooked. The simplified protocol generated 53 selective CT scans, avoiding approximately 144 CT scans. If further simplified by omitting the 1-year CT scan, one type II endoleak would be missed with a 1-year delay, eliminating a further 45 CT scans.

CONCLUSION

US appears comparable to CT in the follow-up of Talent stent grafts in our institution. The proposed simplified surveillance protocol seems safe and can lead to a significant reduction in the number of CT scans.

Are postoperative complications more common following colon and rectal surgery in patients with chronic kidney disease?

AIM

According to National Kidney Foundation guidelines, early stages of chronic kidney disease (CKD) can be detected through the estimated glomerular filtration rate (eGFR). We assessed complications following colorectal surgery (CRS) in patients with CKD Stages 3 and 4, as defined by the eGFR.

METHOD

Patients with CKD were identified within our database. Patients with an eGFR of 15-59 ml/min (CKD Stages 3 and 4) formed the CKD group and were compared with American Society of Anesthesiology (ASA) score-matched controls with an eGFR of ≥ 60 ml/min. Assessments included demographics, comorbidity, ASA score, operative details and 30-day postoperative outcome.

RESULTS

Seventy patients in the CKD group were matched with 70 controls. ASA scores and length of stay did not differ significantly between the groups. CKD patients were older (mean age 76.5 years vs 71.1 years; P < 0.001) and had a lower mean body mass index (24.3 vs 28.2; P < 0.001) compared with controls. Compared with the CKD group, the mean operation time was longer in the control group (181.5 min vs 151.6 min; P = 0.02) and the estimated blood loss was greater (232 ml vs 165 ml; P = 0.004). Postoperative infection was more common in the CKD group (60%vs 40%; P = 0.01). There were no significant differences in reoperation rates, 30-day readmissions or the incidence of acute renal failure (ARF).

CONCLUSION

Patients with CKD Stages 3 and 4 had a higher incidence of postoperative infections than matched controls after colorectal surgery. ARF developed in 18.6% of patients. Preoperative optimization should include adequate hydration and assessment of potentially nephrotoxic substances for bowel preparation, preoperative antibiotics and pain control.

Urinary sodium is a potent correlate of proteinuria: lessons from the chronic renal insufficiency cohort study

BACKGROUND

While higher blood pressure is known to increase proteinuria, whether increased dietary sodium as estimated from 24-hour urinary excretion correlates with increased proteinuria in patients with chronic kidney disease (CKD) is not well studied.

METHODS

We measured 24-hour urinary sodium, potassium and protein excretion in 3,680 participants in the Chronic Renal Insufficiency Cohort study, to determine the relationship between urinary sodium and potassium and urinary protein excretion in patients with CKD. We stratified our data based on the presence or absence of diabetes given the absence of any data on this relationship and evidence that diabetics had greater urinary protein excretion at nearly every level of urinary sodium excretion. Multiple linear regressions were used with a stepwise inclusion of covariates such as systolic blood pressure, demographics, hemoglobin A1c and type of antihypertensive medications to evaluate the relationship between urinary electrolyte excretion and proteinuria.

RESULTS

Our data demonstrated that urinary sodium (+1 SD above the mean), as a univariate variable, explained 12% of the variation in proteinuria (β = 0.29, p < 0.0001), with rising urinary sodium excretion associated with increasing proteinuria. The significance of that relationship was only partially attenuated with adjustment for demographic and clinical factors and the addition of 24-hour urinary potassium to the model (β = 0.13, R(2) = 0.35, p < 0.0001).

CONCLUSIONS

An understanding of the relationship between these clinical factors and dietary sodium may allow a more tailored approach for dietary salt restriction in patients with CKD.

The effects of a novel histamine-3 receptor inverse agonist on essential tremor in comparison to stable levels of alcohol

Essential tremor (ET) is a common movement disorder. Animal studies show that histaminergic modulation may affect the pathological processes involved in the generation of ET. Histamine-3 receptor inverse agonists (H3RIA) have demonstrated attenuating effects on ET in the harmaline rat model. In this double-blind, three-way cross-over, single-dose, double-dummy study the effects of 25 mg of a novel H3RIA (MK-0249) and a stable alcohol level (0.6 g L(-1)) were compared with placebo, in 18 patients with ET. Tremor was evaluated using laboratory tremorography, portable tremorography and a clinical rating scale. The Leeds Sleep Evaluation Questionnaire (LSEQ) and a choice reaction time (CRT) test were performed to evaluate potential effects on sleep and attention, respectively. A steady state of alcohol significantly diminished tremor as assessed by laboratory tremorography, portable tremorography and clinical ratings compared with placebo. A high single MK-0249 dose was not effective in reducing tremor, but caused significant effects on the LSEQ and the CRT test. These results suggest that treatment with a single dose of MK-0249 does not improve tremor in alcohol-responsive patients with ET, whereas stable levels of alcohol as a positive control reproduced the commonly reported tremor-diminishing effects of alcohol.

Surgical resection in Crohn's disease: is immunosuppressive medication associated with higher postoperative infection rates?

AIM

The aim of this study was to analyse postoperative infection in patients undergoing surgery for Crohn's disease (CD) according to the use of preoperative immunosuppressants, including infliximab.

METHOD

With IRB approval, the records of all patients with CD who underwent abdominal surgery between 2001 and 2008 were reviewed for comorbidity, preoperative medication, type of surgery, stoma construction and postoperative complications. Patients were divided into three categories according to the preoperative medication within 90 days of surgery as follows: infliximab (IFX), other drugs including steroids and/or immunosuppressive agents (OD) and no drugs (ND).

RESULTS

Two hundred and twenty-five patients were identified. Preoperative comorbidity, surgical indication and type of surgery were not significantly different among the three groups. Ileocolic resection was the most common procedure [50.8%, IFX group; 61.2%, OD group; 41.3%, ND group (P = 0.09)]. Other procedures included total colectomy (16%), protectomy (15%) and others (18%). Laparoscopic surgery was performed in 47.7%, 45.9% and 29.3% of patients in the IFX, OD and ND groups, respectively (P = 0.04). There were no differences in postoperative rates of infection [pneumonia (P = 0.14), wound infection (P = 0.35), abscess (P = 0.34) or anastomotic leakage (P = 0.44)]. Reoperation was needed in 3.0%, 8.2% and 2.6% of patients in the IFX, OD and ND groups, respectively. Multiple logistic regression found no relationship between infliximab use and infection.

CONCLUSION

There was no difference in the rate of postoperative complications among the groups of patients undergoing surgery for CD pretreated with IFX or other immunosuppressive drugs.

Surgical resection in Crohn's disease: is immunosuppressive medication associated with higher postoperative infection rates?

AIM

The aim of this study was to analyse postoperative infection in patients undergoing surgery for Crohn's disease (CD) according to the use of preoperative immunosuppressants, including infliximab.

METHOD

With IRB approval, the records of all patients with CD who underwent abdominal surgery between 2001 and 2008 were reviewed for comorbidity, preoperative medication, type of surgery, stoma construction and postoperative complications. Patients were divided into three categories according to the preoperative medication within 90 days of surgery as follows: infliximab (IFX), other drugs including steroids and/or immunosuppressive agents (OD) and no drugs (ND).

RESULTS

Two hundred and twenty-five patients were identified. Preoperative comorbidity, surgical indication and type of surgery were not significantly different among the three groups. Ileocolic resection was the most common procedure [50.8%, IFX group; 61.2%, OD group; 41.3%, ND group (P = 0.09)]. Other procedures included total colectomy (16%), protectomy (15%) and others (18%). Laparoscopic surgery was performed in 47.7%, 45.9% and 29.3% of patients in the IFX, OD and ND groups, respectively (P = 0.04). There were no differences in postoperative rates of infection [pneumonia (P = 0.14), wound infection (P = 0.35), abscess (P = 0.34) or anastomotic leakage (P = 0.44)]. Reoperation was needed in 3.0%, 8.2% and 2.6% of patients in the IFX, OD and ND groups, respectively. Multiple logistic regression found no relationship between infliximab use and infection.

CONCLUSION

There was no difference in the rate of postoperative complications among the groups of patients undergoing surgery for CD pretreated with IFX or other immunosuppressive drugs.

Granulomas in Crohn's disease: does progression through the bowel layers affect presentation or predict recurrence?

AIM

The aim of the study was to correlate the presence and pattern of distribution of granulomas in resected specimens to clinical characteristics and outcome in patients undergoing surgery for Crohn's disease.

METHOD

Patients with Crohn's disease who underwent surgical resection between 2001 and 2007 were identified. Pathology slides were reviewed for the presence, number and location of granulomas in four representative slides from each specimen.

RESULTS

Two-hundred and seven patients were identified. At a mean follow up of 14 months, 39 patients had a recurrence, 22 (57%) of whom underwent reoperation. Ninety-four (45%) patients had granulomas present in the surgical specimen. Patients with granulomas were younger (P<0.001), had a lower preoperative body mass index (P=0.037), were more likely to be female (P=0.017) and were more likely to have extra-intestinal manifestations (P=0.026) or perianal disease (P=0.012). Sites of disease and procedures performed were similar in both groups. Disease recurrence and reoperative rates were similar in both groups, as were length of stay and morbidity rates. The average number of granulomas present in each sampled pathology slide was 7.2, and there was no correlation between number of granulomas and disease severity. No link was found between the depth of involvement of the granulomas and fistulizing or stricturing disease.

CONCLUSION

Granulomas were associated with increased extra-intestinal manifestations and perianal disease, a lower body mass index and younger or female patients. There was no correlation between the presence of granulomas and disease progression or recurrence rates during the short follow-up period of this study.