Enterocutaneous fistulas: causes, management, and Emory authors

One discussion this week involved enterocutaneous fistulas.

Reference: Haak CI, Galloway JR, Srinivasan J. Enterocutaneous fistulas: a look at causes and management. Current Surgery Reports. 2014 Oct;2:71.

Summary: Despite advances in medical technology and surgical care, the management of enterocutaneous fistulas (ECF) remains one of the most challenging problems faced by physicians. Success depends on an expert multidisciplinary team, access to long-term enteral and parenteral nutrition support, advanced wound care, optimal medical management and meticulous, methodical, surgical decision-making and technique.

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Meta-analysis, systematic review of carbonic anhydrase inhibitors in respiratory failure and metabolic alkalosis

One discussion this week involved carbonic anhydrase inhibitors (CAIs) in the setting of respiratory failure and metabolic alkalosisa.

Reference: Tanios BY, et al. Carbonic anhydrase inhibitors in patients with respiratory failure and metabolic alkalosis: a systematic review and meta-analysis of randomized controlled trials. Critical Care. 2018 Oct 29;22(1):275.  doi: 10.1186/s13054-018-2207-6

Summary: Metabolic alkalosis is common in patients with respiratory failure and may delay weaning in mechanically ventilated patientsCarbonic anhydrase inhibitors (such as acetazolamide, methazolamide, and dichlorphenamide) block renal bicarbonate reabsorption, and thus reverse metabolic alkalosis. However, uncertainty remains about
their effects in the setting of respiratory failure with concurrent metabolic alkalosis on duration of hospitalization, mechanical ventilation (MV), or noninvasive positive pressure ventilation (NIPPV), and mortality.

The objective of this systematic review is to assess the benefits and harms of carbonic anhydrase inhibitor therapy in patients with respiratory failure and metabolic alkalosis.

Randomized clinical trials were included if they assessed at least one of the following outcomes: mortality, duration of hospital stay, duration of mechanical ventilation, adverse events, and blood gas parameters. Six eligible studies were identified with a total of 564 patients.

There were no definitive results for the effects of CAI therapy on clinically important outcomes such as mortality and duration of hospital stay in patients with respiratory failure and metabolic alkalosis. The results suggest that CAI therapy may decrease the duration of mechanical ventilation. There was a trend towards increased incidence of adverse events in the CAI group; however, most of these adverse events were mild.

On the other hand, the results suggest that CAI therapy has favorable effects on arterial blood gas parameters (PaCO2, PaO2, bicarbonate and pH), with decreased PaCO2, increased PaO2, and, as expected, decreased bicarbonate and pH levels.

Conclusion

In patients with respiratory failure and metabolic alkalosiscarbonic anhydrase inhibitor therapy may have favorable effects on blood gas parameters. The authors note that this analysis did not provide conclusive results for clinically important outcomes.

In mechanically ventilated patientscarbonic anhydrase inhibitor therapy may decrease the duration of mechanical ventilation. A major limitation was that only two trials assessed this clinically important outcome.

Ureteral catheters and injury during colectomy: A NSQIP study

One discussion this week included ureteral injuries during colectomy.


Reference: Coakley KM, et al. Prophylactic ureteral catheters for colectomy: A National Surgical Quality Improvement Program-based analysis. Diseases of the Colon and Rectum. 2018 Jan;61(1):84-88. doi:10.1097/DCR.0000000000000976.

Summary: Despite improvement in technique and technology, using prophylactic ureteral catheters to avoid iatrogenic ureteral injury during colectomy remains controversial. The aim of this retrospective study was to evaluate outcomes and costs attributable to prophylactic ureteral catheters with colectomy. Conducted at a signle tertiary care center, the authors pulled clinical data, 2012-2014, from ACS NSQIP database.

A total of 51,125 patients were identified with a mean age of 60.9 ± 14.9 years and a BMI of 28.4 ± 6.7 k/m; 4.90% (n = 2486) of colectomies were performed with prophylactic catheters, and 333 ureteral injuries (0.65%) were identified.

  • Prophylactic ureteral catheters were most commonly used for diverticular disease (42.2%; n = 1048), with injury occurring most often during colectomy for diverticular disease (36.0%; n = 120).
  • Univariate analysis of outcomes demonstrated higher rates of ileus, wound infection, urinary tract infection, urinary tract infection as reason for readmission, superficial site infection, and 30-day readmission in patients with prophylactic ureteral catheter placement.
  • On multivariate analysis, prophylactic ureteral catheter placement was associated with a lower rate of ureteral injury (OR = 0.45 (95% CI, 0.25-0.81)).
  • Additional research is needed to delineate patient populations most likely to benefit from prophylactic ureteral stent placement.

Open vs closed hemorrhoidectomy: a systematic review and meta-analysis of RCTs

One discussion this week included open versus closed hemorrhoidectomy.

Reference: Bhatti M, Sajid MS, Baig MK. Milligan-Morgan (open) versus Ferguson haemorrhoidectomy (closed): A systematic review and meta-analysis of published randomized, controlled trails. World Journal of Surgery. 2016 Jun;40(6):1509-1519. doi:10.1007/s00268-016-3419-z.

Summary: In Europe, the Milligan-Morgan procedure or open haemorrhoidectomy (OH) is more frequently practised, whereas in the United States of America the closed haemorrhoidectomy (CH) procedure, as described by Ferguson and Heaton, is the most popular. CH is purported to be a less painful procedure and associated with faster wound healing due to primary wound closure. However, the conflicting outcomes following both procedures have been debated in the published literature and several controversies around post-operative pain still need clarification.

Relevant prospective randomized, controlled trials (irrespective of type, language, gender, blinding, sample size or publication status) on CH versus OH for the management of HD until May 2014 were included in this review.

Ultimately, 11 RCTs encompassing 1326 patients were included in the systematic review and meta-analysis. Significant heterogeneity was found among included trials.

CONCLUSIONS: Variables of pain on defecation, length of hospital stay, post-operative complications, HD recurrence and risk of surgical site infection were similar in both groups.

Based upon the findings of this review, CH was associated with a reduced post-operative pain, faster wound healing, lesser risk of post-operative bleeding but prolonged duration of operation.

Findings of this review are contradictory to a 2007 meta-analysis of six randomized, controlled trials.

 

To view full data analyses (3 tables and 11 figures!) click on the link in the reference at the top of this post.

 

Will there be positive neurological outcomes after ECMO resuscitation?

One discussion this week involved neurological outcomes following ECMO resuscitation.


Reference: Ryu JA, et al. Predictors of neurological outcomes after successful extracorporeal cardiopulmonary resuscitation. BMC Anesthesiology. 2015 Mar 8;15:26. doi: 10.1186/s12871-015-0002-3

Summary: Extracorporeal membrane oxygenation (ECMO) is a useful intervention for refractory cardiogenic shock and respiratory failure. Because ECMO implementation can rapidly normalize circulation in patients under cardiac arrest, it has been used to assist cardiopulmonary resuscitation (CPR). Using traditional chest compression is less effective than using ECMO with CPR (known as extracorporeal CPR or ECPR). ECPR can achieve more effective recovery of spontaneous circulation (ROSC) than conventional CPR.

Since the brain is the organ most vulnerable to hypoxia and inadequate perfusion, ECPR can result in severe neurologic deficits if ECMO is not performed promptly. In addition to delay, several factors may lead to poor neurological outcomes after ECPR. Achieving good neurological outcomes and successful resuscitation are important, so the authors investigated predictors of favorable neurological outcomes rather than survival after ECPR.

The study’s primary endpoint was neurological outcome at hospital discharge, assessed with the Glasgow-Pittsburgh Cerebral Performance Categories (CPC) scale (1 to 5, as shown in Table 1). CPC 1 and 2 were classified as good neurological outcomes. CPC 3, 4, and 5 were considered poor neurological outcomes.

Of 115 patients, 68 (59%) had good neurological outcomes but 47 (41%) did not (Figure 2). Therapeutic hypothermia was performed in 10 patients (5%). Mean duration of ECMO support was 47.5 (range 18.5–101) hours. Total length of stay in intensive care unit (ICU) was 11 (range 7–22.5) days and 24 patients died from brain death.

Univariate analysis showed no differences between the good and poor neurological outcome groups for age, comorbidities, bystander CPR, therapeutic hypothermia, total bilirubin, creatinine, 24-hour lactic acid clearance, ROSC before ECMO, or ROSC time (Table 2).

Multivariate analysis revealed neurological outcomes were affected by hemoglobin level, serum lactic acid before ECMO insertion, and interval from cardiac arrest to ECMO (Figure 3). However, age, gender, cardiac arrest out of the hospital, hemoglobin level after ECMO, acute coronary syndrome, initial shockable rhythm, and CPR duration were not independent predictors of neurological outcomes (Table 3).

Risk of acute kidney injury in patients on vancomycin

One discussion this week included the use of vancomycin in the setting of acute kidney injury (AKI).

Reference: Navalkele B, et al. Risk of acute kidney injury in patients on concomitant vancomycin and piperacillin-tazobactam compared to those on vancomycin and cefepime. Clinical Infectious Diseases. 2017 Jan 15;64(2):116-123. doi:10.1093/cid/ciw709.

Summary: In a retrospective, matched, cohort study of 558 patients, Navlkele et al (2017) compared the incidence of AKI among patients receiving combination therapy with vancomycin + piperacillin-tazobactam (VPT) to a matched group receiving vancomycin + cefepime (VC).

AKI rates were significantly higher in the VPT group than the VC group (81/279 [29%] vs 31/279 [11%]). In multivariate analysis, therapy with VPT was an independent predictor for AKI (hazard ratio = 4.27; 95% confidence interval, 2.73-6.68). Among patients who developed AKI, the median onset was more rapid in the VPT group compared to the VC group (3 vs 5 days P =< .0001).

Effectiveness of pyloric exclusion (PEX) in treating duodenal trauma

One discussion this week involved the use of pyloric exclusion (PEX) for management of severe duodenal injuries.

References: DuBose JJ, et al. Pyloric exclusion in the treatment of severe duodenal injuries: results from the National Trauma Data Bank. The American Surgeon. 2008 Oct;74(10):925-929.

Malhotra A, et al. Western Trauma Assoication Critical Decisions in Trauma: Diagnosis and management of duodenal injuries. Journal of Trauma and Acute Care Surgery. 2015 Dec;79(6):1096-1101. doi: 10.1097/TA.0000000000000870

Summary: Using the American College of Surgeons National Trauma Data Bank (v 5.0), DuBose et al (2008) evaluated adult patients with severe duodenal injuries [AAST Grade > or = 3] undergoing primary repair only or repair with PEX within 24 hours of admission.  Of the 147 patients, 28 (19.0%) underwent PEX [15.9% (11/69) Grade III vs 34.0% (17/50) Grade IV-V]. Their main findings were:

  • PEX was associated with a longer mean hospital stay (32.2 vs 22.2 days, P = 0.003).
  • PEX was not associated with a mortality benefit.
  • There was a trend toward increased development of septic abdominal complications (intra-abdominal abscess, wound infection, or dehiscence) with PEX that was not statistically significant.
  • After multivariable analysis using propensity score, no statistically significant differences in mortality or occurrence of septic abdominal complications was noted between those patients undergoing primary repair only or PEX.

DuBose et al (2008) conclude that the use of PEX in patients with severe duodenal injuries may contribute to longer hospital stay and confers no survival or outcome benefit.

The Western Trauma Association guidelines for management of duodenal injuries (Malhotra et al, 2015) include the algorithm below for determining management:

duodenal screenshot

Additional reading: Ginzburg E, et al. Pyloric exclusion in the management of duodenal trauma: is concomitant gastrojejunostomy necessary? The American Surgeon. 1997 Nov;63(11):964-966.

Lobectomy vs total thyroidectomy for intermediate-size papillary thyroid cancer

One discussion last week included the extent of surgery for intermediate-size papillary thyroid cancer: lobectomy vs total thyroidectomy.


Reference: Adam MA, et al. Extent of surgery for papillary thyroid cancer is not associated with survival: an analysis of 61,775 patients. Annals of Surgery. 2014 Oct;260(4):601-605. doi:10.1097/SLA.0000000000000925.

Summary: Guidelines recommend total thyroidectomy for PTC tumors >1 cm, based on older data demonstrating an overall survival advantage for total thyroidectomy over lobectomy.

Adult patients with PTC tumors 1.0-4.0 cm undergoing thyroidectomy in the National Cancer Database between 1998-2006 were included, totaling 61,775 patients. Median follow-up was 82 months (range, 60-179 months).

Lobectomy (n=6849)

Total thyroidectomy (n=54,926)

Nodal disease

7%

27%

Extrathyroidal disease

5%

16%

Multifocual disease

29%

44%

After multivariable adjustment, overall survival was similar in patients undergoing total thyroidectomy versus lobectomy for tumors 1.0-4.0 cm and when stratified by tumor size: 1.0-2.0 cm and 2.1-4.0 cm. Older age, male sex, black race, lower income, tumor size, and presence of nodal or distant metastases were independently associated with compromised survival (P < 0.0001).

Adam et al (2014) conclude that although current guidelines suggest total thyroidectomy for PTC tumors >1 cm, they did not observe a survival advantage associated with total thyroidectomy compared with lobectomy. These findings call into question whether tumor size should be an absolute indication for total thyroidectomy.

Treatment in uremic bleeding

One discussion this week involved the treatment for uremic bleeding.


Reference: Hedges SJ, et al. Evidence-based treatment recommendations for uremic bleedingNational Clinical Practice. Nephrology. 2007 Mar;3(3):138-153.

Summary: Hedges et al (2007) provide a review of normal hemostatic and homeostatic mechanisms that operate within the body to prevent unnecessary bleeding, as well as an in-depth discussion of the dysfunctional components that contribute to complications associated with uremic bleeding syndrome. Prevention and treatment options can include one or a combination of the following: dialysis, erythropoietin, cryoprecipitate, desmopressin, and conjugated estrogens.

The article cited is worth a full text read because:

  • Treatment options are compared with regard to their mechanism of action, and onset and duration of efficacy.
  • An extensive review of the clinical trials that have evaluated each treatment is also presented (Tables 3, 4, 5).
  • An evidence-based treatment algorithm to help guide clinicians through most clinical scenarios, and address common questions related to the management of uremic bleeding.

Uremic bleeding in patients with chronic renal failure is extremely complex. One factor contributing to this complexity is the incomplete elucidation of its pathophysiology. Because the mechanisms underlying uremic bleeding are not fully understood, prevention and treatment for many different clinical scenarios are not clearly defined (p.150).

  • EPO works to increase the number of red blood cells, allowing platelets to travel in closer proximity to the endothelium.
  • Cryoprecipitate and desmopressin work to increase the proportion of normal or functional factors that might be dysfunctional in patients with uremic bleeding.
  • Estrogens are thought to work by decreasing NO levels, thereby increasing concentrations of TxA2 and ADP.

Multiple interventions that simultaneously affect different aspects of the pathophysiology of uremic bleeding might most effectively prevent bleeding in high-risk patients and limit active bleeding in those for who cessation of blood loss is more pressing.

By determining which patients are most at risk, clinicians can utilize dialysis and EPO in the early stages of uremic bleeding, and employ desmopressin, cryoprecipitate and/or estrogens prior to a surgical procedure, thereby possibly preventing bleeding secondary to uremic platelet dysfunction.

Readmission rates following parathyroidectomy for renal disease

One discussion this week included readmission rates following parathyroidectomy.


References: Ferrandino R, et al. Unplanned 30-day readmissions after parathyroidectomy in patients with chronic kidney disease: a nationwide analysis. Otolaryngology – Head and Neck Surgery. 2017 Dec;157(6):955-965. doi:10.1177/0194599817721154.

Summary: A retrospective cohort study was performed using the 2013 Nationwide Readmissions Database (NRD) of the Healthcare Cost and Utilization Project (HCUP) from the Agency for Healthcare Research and Quality (AHRQ). In a total of 2756 parathyroidectomies performed in patients with chronic kidney disease, 17.2%  had at least one unplanned readmission rate within the first 30-days, and 2.4% had more than one readmission. Overall, readmission rates for chronic kidney disease patients are nearly 5-times that of the general population (Ferrandino et al, 2017).

Hypocalcemia/hungry bone syndrome accounted for 40% of readmissions. While readmissions occurred uniformly throughout the 30 days after discharge, those for hypocalcemia/hungry bone syndrome peaked in the first 10 days and decreased over time.

Weight loss/malnutrition at time of parathyroidectomy and length of stay of 5-6 days conferred increased risk of readmission with adjusted odds ratios of 3.31 and 1.87, respectively. Relative to primary hyperparathyroidism, parathyroidectomies performed for secondary hyperparathyroidism were associated with higher risk of readmission.

The authors conclude: “While there are few patient-specific predictors of readmission, we note that the bulk of these readmissions can be attributed to hypocalcemia. To improve readmission rates after parathyroidectomy in CKD patients, we propose focusing on accurate, appropriate medication reconciliation, and optimizing communication and transitions of care to outside facilities (skilled nursing, dialysis, etc.) to facilitate the comprehensive care of this high-risk patient population” (Ferrandino et al, p.964).

Additional Reading: Sharma J, et al. Improved long-term survival of dialysis patients after near-total parathyroidectomy. Journal of the American College of Surgeons. 2012 Apr;214(4):400-407. doi:10.1016/j.jamcollsurg.2011.12.046.

Westerdahl J, et al. Risk factors for postoperative hypocalcemia after surgery for primary hyperparathyroidism. Archives of Surgery. 2000 Feb;135(2):142-147.