Real world efficacy of alvimopan on elective bowel resection patients: an analysis of statistical versus clinical significance

Effect of Alvimopan on Postoperative Ileus and Length of Hospital Stay in Patients Undergoing Bowel Resection: A Systematic Review and Meta-Analysis

AIMS

The aim is to investigate the effect of alvimopan on postoperative ileus and length of hospital stay in patients undergoing bowel resection.

METHODS

The PRISMA statement standards were followed to conduct a systematic review and meta-analysis. The available literature was searched to identify all studies comparing alvimopan with no alvimopan in patients undergoing bowel resection. Postoperative ileus and length of hospital stay were the primary outcomes, and time to first bowel motion was the secondary outcome. Random-effects modeling was applied for analyses.

RESULTS

Analysis of 94 833 patients from 26 studies showed that alvimopan was associated with lower risk of postoperative ileus (OR: .57, 95% CI .48 to .67, P <.00001; high GRADE certainty), shorter length of hospital stay (MD: -1.08 day, 95% CI -1.36 to -.81, P < .00001; moderate GRADE certainty), and shorter time to first bowel motion (MD: -.43 day, 95% CI -.58 to -.28, P < .00001; moderate GRADE certainty). Separate analyses of randomized controlled trials and observational studies showed similar findings. Subgroup analyses suggested consistent findings in patients undergoing elective bowel resection, emergency bowel resection, and open surgery; however, alvimopan did not improve the outcomes in patients undergoing minimally invasive surgery.

CONCLUSION

Robust evidence supports the routine use of alvimopan in patients undergoing open bowel resection as indicated by lower risk of postoperative ileus and shorter length of hospital stay. We support incorporation of alvimopan into enhanced recovery after surgery programs for the procedures involving open bowel resection. The role of alvimopan in minimally invasive bowel resection needs more research.

Selective Opioid Antagonists Following Bowel Resection for Prevention of Postoperative Ileus: a Systematic Review and Meta-analysis

BACKGROUND

Postoperative ileus (POI) remains a common complication following bowel resection. Selective opioid antagonists have been increasingly studied as prophylactic pharmaceutical aids to reduce rates of POI. The aim of this study was to evaluate the impact of selective opioid antagonists on return of bowel function following bowel resection.

METHODS

MEDLINE, Embase, and CENTRAL were systematically searched. Articles were included if they compared the incidence of POI and/or length of stay (LOS) in patients receiving and not receiving selective opioid antagonists following elective bowel resection. A pairwise meta-analyses using inverse variance random effects was performed.

RESULTS

From 636 citations, 30 studies with 45,051 patients receiving selective opioid antagonists (51.3% female, mean age: 60.9) and 55,071 patients not receiving selective opioid antagonists (51.2% female, mean age: 61.1) were included. Patients receiving selective opioid antagonists had a significantly lower rate of POI (10.1% vs. 13.8%, RR 0.68, 95%CI 0.63-0.75, p < 0.01). Selective opioid antagonists also significantly reduced LOS (MD - 1.08, 95%CI - 1.47 to - 0.69, p < 0.01), readmission (RR 0.94, 95%CI 0.89-0.99, p = 0.03), and 30-day morbidity (RR 0.85, 95%CI 0.79-0.90, p < 0.01). Improvements in LOS, readmission rate, and morbidity were not significant when analysis was limited to laparoscopic surgery. There was no significant difference in inpatient healthcare costs (SMD - 0.33, 95%CI - 0.71-0.04, p = 0.08).

CONCLUSIONS

Rate of POI decreases with the use of selective opioid antagonists in patients undergoing bowel resection. Selective opioid antagonists also improve LOS, rates of readmission, and 30-day morbidity for patients undergoing open bowel resection. Addition of these medications to enhance recovery after surgery protocols should be considered.

The association of alvimopan treatment with postoperative outcomes after abdominal surgery: A systematic review across different surgical procedures and contexts of perioperative care

BACKGROUND

Alvimopan is a Food and Drug Administration-approved treatment to accelerate gastrointestinal recovery after abdominal surgery; however, benefits may vary across different procedures and contexts of care. The purpose of this study is to summarize the evidence regarding the effect of alvimopan on postoperative outcomes after abdominal surgery.

METHODS

Major databases (Medline, Embase, Biosis, Cochrane, Web of Science, and Scopus) were searched for randomized controlled trials and nonrandomized studies comparing alvimopan versus control. Risk of bias was assessed using Cochrane's risk of bias tool 2.0 (for randomized controlled trials) and Risk of Bias in Nonrandomized Studies-of Intervention tool (for nonrandomized studies). Results were appraised descriptively as heterogeneity in reporting and risk of bias hindered meta-analysis. Quality of evidence across different surgical procedures and contexts of care (ie, open versus minimally invasive surgery, traditional care versus enhanced recovery pathway) was evaluated using Grading of Recommendations Assessment, Development, and Evaluation.

RESULTS

Nine randomized controlled trials and 35 nonrandomized studies were identified. Evidence of low to moderate certainty supports that alvimopan reduces length of stay and improves gastrointestinal recovery after open bowel resection and open radical cystectomy. Limited evidence supports alvimopan for surgeries not listed in Food and Drug Administration labels (ie, total abdominal hysterectomy and retroperitoneal lymph node dissection). Similar effects were observed in traditional and enhanced recovery pathway settings, but enhanced recovery pathway elements varied across studies. There is very low certainty of evidence supporting alvimopan for patients undergoing minimally invasive surgery.

CONCLUSION

Evidence supports that alvimopan improves outcomes after open bowel resection and open radical cystectomy. Benefits for patients undergoing minimally invasive surgery and treated in contemporary enhanced recovery pathway settings remain uncertain. These findings contribute important new knowledge to inform evidence-based alvimopan prescribing.

Acute Colonic Pseudo-Obstruction After Posterior Spinal Fusion: A Case Report and Literature Review

BACKGROUND

Acute colonic pseudo-obstruction (ACPO) or Ogilvie's syndrome occurs in 0.22%-7% of patients undergoing surgery, with a mortality of up to 46%. ACPO increased median hospital days versus control in spinal surgery (14 vs. 6 days; P < 0.001). If defined as postoperative ileus, the incidence was 7%-13.4%. Postoperative ileus is associated with 2.9 additional hospital days and an $80,000 increase in cost per patient. We present a case of ACPO in an adult patient undergoing spinal fusion for correction of scoliosis and review the available literature to outline clinical characteristics and surgical outcomes.

CASE DESCRIPTION

The patient was a 31-year-old woman with untreated advanced scoliosis with no history of neurologic issues. T2-L3 spinal instrumentation and fusion was completed. Plain abdominal radiography showed of dilated cecum 11 cm and the department of general surgery was consulted. Neostigmine administration was planned after conservative treatment failure after transfer to the intensive care unit. The patient was discharged home with no recurrence >60 days. Thirty cases were found in our literature review using PubMed and Embase databases and summarized.

CONCLUSIONS

Of 30 cases reviewed, only 3 cases of ACPO were specific to patients undergoing spinal fusion for scoliosis. According to the literature, 20% of patients had resolution with conservative treatment, 40% with neostigmine, and 30% with surgical intervention. Other noninvasive treatments may have similar efficacy in preventing complications leading to surgical invention. Sixty clinical trials and 9 systematic reviews were summarized with an updated management algorithm.

Alvimopan Significantly Reduces Length of Stay and Costs Following Colorectal Resection and Ostomy Reversal Even Within an Enhanced Recovery Protocol

BACKGROUND

Alvimopan accelerates GI recovery after colorectal resection. Data on real-world cost-effectiveness have been mixed.

OBJECTIVE

This study aimed to evaluate if adding alvimopan to an enhanced recovery pathway reduces length of stay.

DESIGN

Patients undergoing colorectal resection or ostomy reversal for the year before and after the introduction of alvimopan were evaluated.

SETTING

This study was conducted at a single academic medical center.

PATIENTS

Patients undergoing elective colorectal resection (488) or ostomy reversal (148) were included.

MAIN OUTCOME MEASURES

The primary outcomes measured were length of stay and prolonged length of stay defined as >75th percentile for each procedure.

RESULTS

Two hundred eighty-six patients (45%) received alvimopan. Alvimopan and no-alvimopan groups had similar demographics, comorbidities, operative indication, and case mix. In the alvimopan group, more of the colorectal resections were laparoscopic (87% vs 79%, p = 0.015). Length of stay was reduced with alvimopan (6.2 vs 4.9 days, p = 0.003), and this effect persisted when controlling for procedure type, approach, and ASA class (decreased length of stay by 1.0 day, p = 0.014). The alvimopan group had lower risk of prolonged length of stay (14.7% vs 23.1%, p = 0.007) and ileus (10.8% vs 16.2%, p = 0.05). On multivariable analysis, no alvimopan use (OR, 1.8; 95% CI, 1.2-2.7), ASA ≥3 (OR, 2.0; 95% CI, 1.3-3.1), and history of cardiac surgery (OR, 2.8; 95% CI, 1.2-6.5) were significant predictors of prolonged length of stay. Alvimopan use was associated with a lower risk of infectious complications other than surgical site infection (2.8% vs 6.7%, p = 0.025), and did not increase risk of any adverse outcomes. The addition of alvimopan to the protocol resulted in cost savings of $708.39 per patient.

LIMITATIONS

Data collected from a single center limit external validity.

CONCLUSIONS

The introduction of alvimopan to a postoperative protocol following elective colorectal resection or ostomy reversal significantly reduces length of stay and is associated with cost savings even within an enhanced recovery protocol. See Video Abstract at http://links.lww.com/DCR/A911.

Facilitating return of bowel function after colorectal surgery: alvimopan and gum chewing

Postoperative ileus is common after colorectal surgery, and has a huge impact on hospital LOS. With the impeding cost crisis in the United States, safely reducing length of stay is essential. Chewing gum and pharmacological treatment with alvimopan are safe, simple tools to reduce postoperative ileus and its associated costs. Future research will determine if integrating these tools with laparoscopic procedures and enhanced recovery pathways is a best practice in colorectal surgery.

Methylnaltrexone for the treatment of opioid-induced constipation

Opioids are the drugs of choice for treating moderate-to-severe pain, especially for patients in the end stage of cancer or other advanced illnesses, and also in critical care or for the treatment of chronic pain. Side effects such as nausea, pruritus, dizziness and constipation have to be controlled in order to use these drugs to their full potential. Opioid-induced bowel syndrome and constipation caused by activation of μ-receptors in the gut can have such distressing effects that some patients prefer to forego adequate pain control. Methylnaltrexone is a μ-opioid receptor antagonist that, unlike naltrexone or naloxone, does not pass the blood-brain barrier, and therefore does not impair the centrally mediated analgesic effect of opioids. It is licensed for the treatment of opioid-induced constipation in palliative care in more than 50 countries. This article presents practically relevant pharmacological data, basic research results and evidence from clinical research about methylnaltrexone, and outlines potential future therapeutic options for this promising drug.