Author Archives: Hannah

Laparoscopic entry techniques

Posted on by
Reply

One discussion this week involved laparoscopic entry techniques.

Reference: Ahmad G, et al. Laparoscopic entry techniques. The Cochrane Database of Systematic Reviews. 2019 Jan 18;1:CD006583. doi: 10.1002/14651858.CD006583.pub5

Summary: In their updated systematic review on the topic, Ahmed et al (2019) included 57 RCTs including four multi-arm trials, with a total of 9865 participants, and evaluated 25 different laparoscopic entry techniques.

Overall, evidence was insufficient to support the use of one laparoscopic entry technique over another. Researchers noted an advantage of direct trocar entry over Veress needle entry for failed entry. Most evidence was of very low quality; the main limitations were imprecision (due to small sample sizes and very low event rates) and risk of bias associated with poor reporting of study methods.

Open-entry vs closed-entry: Evidence was insufficient to show whether there were differences between groups for:

  • vascular injury (Peto OR 0.14, 95% CI 0.00 to 6.82; 4 RCTs; n=915; I²=N/A)
  • visceral injury (Peto OR 0.61, 95% CI 0.06 to 6.08; 4 RCTs; n=915: I²=0%)
  • failed entry (Peto OR 0.45, 95% CI 0.14 to 1.42; 3 RCTs; n=865; I²=63%)

Direct trocar vs Veress needle entry: Trial results show a reduction in failed entry into the abdomen with the use of a direct trocar in comparison with Veress needle entry (Peto OR 0.24, 95% CI 0.17 to 0.34; 8 RCTs; n=3185; I²=45%; moderate-quality evidence).

Direct vision entry vs Veress needle entry: Evidence was insufficient to show whether there were differences between groups in rates of:

  • vascular injury (Peto OR 0.39, 95% CI 0.05 to 2.85; 1 RCT; n=186)
  • visceral injury (Peto OR 0.15, 95% CI 0.01 to 2.34; 2 RCTs; n=380; I²=N/A)

Direct vision entry vs open entry: Evidence was insufficient to show whether there were differences between groups in rates of:

  • visceral injury (Peto OR 0.13, 95% CI 0.00 to 6.50; 2 RCTs; n=392; I²=N/A)
  • solid organ injury (Peto OR 6.16, 95% CI 0.12 to 316.67; 1 RCT; n=60)
  • failed entry (Peto OR 0.40, 95% CI 0.04 to 4.09; 1 RCT; n=60)

Radially expanding (STEP) trocars vs non-expanding trocars: Evidence was insufficient to show whether there were differences between groups in rates of:

  • vascular injury (Peto OR 0.24, 95% Cl 0.05 to 1.21; 2 RCTs; n=331; I²=0%)
  • visceral injury (Peto OR 0.13, 95% CI 0.00 to 6.37; 2 RCTs; n=331)
  • solid organ injury (Peto OR 1.05, 95% CI 0.07 to 16.91; 1 RCT; n=244)

(Ahmed et al, 2019, p.2)

PROSPER trial: A comparison of treatments for rectal prolapse

Posted on by
Reply

One discussion this week involved the PROSPER trial of treatment for rectal prolapse.

References: Senapati A, et al. PROSPER: a randomised comparison of surgical treatments for rectal prolapse. Colorectal Disease. 2013 Jul;15(7):858-868. doi:10.1111/codi.12177

Summary: The PROSPER randomised control trial is a pragmatic, factorial (2 × 2) design trial in which 293 patients were randomised between abdominal and perineal surgery (i) (n=49), suture vs resection rectopexy for those receiving an abdominal procedure (ii) (n=78), or Altemeier’s vs Delorme’s for those receiving a perineal procedure (iii) (n=213). Primary outcome measures were recurrence of the prolapse, incontinence, bowel function and quality of life scores measured up to 3 years.

Recurrence rates were not significant in any comparisons:

  • abdominal vs perineal surgery: 20% vs 26%
  • suture vs resection rectopexy: 13% vs 26%
  • Altemeier’s vs Delorme’s: 24% vs 31%

It was noted that substantial improvements from baseline in quality of life following all procedures. Additionally, Vaizey, bowel thermometer and EQ-5D scores were not significantly different in any of the comparisons (Senapati et al, 2013).

Additional Reading: Bordeianou L, et al. Clinical practice guidelines for the treatment of rectal prolapse. Diseases of the Colon and Rectum. 2017 Nov;60(11):1121-1131. doi:10.1097/DCR.0000000000000889

Perioperative fluid management: restrictive vs liberal regimens

Posted on by
Reply

One discussion this week included restrictive vs liberal perioperative fluid management on the development of perioperative acute kidney injury.

References: Brandstrup B, et al. Effects of intravenous fluid restriction on postoperative complications: comparison of two perioperative fluid regimens: a randomized assessor-blinded multicenter trial. Annals of Surgery. 2003 Nov;238(5):641-648.

Myles PS, et al. Restrictive versus liberal fluid therapy for major abdominal surgery. NEJM. 2018 Jun 14;378:2263-2274. doi:10.1056/NEJMoa1801601

Summary: Traditional intravenous-fluid regimens administered during abdominal surgery deliver up to 7 liters of fluid on the day of surgery. Some small trials have shown that a more restrictive fluid regimen led to fewer complications and a shorter hospital stay. However, the evidence for fluid restriction during and immediately after abdominal surgery is inconclusive. Fluid restriction could increase the risk of hypotension and decrease perfusion in the kidney and other vital organs, leading to organ dysfunction, but excessive intravenous-fluid infusion may increase the risk of pulmonary complications, acute kidney injury, sepsis, and poor wound healing (Myles 2018).

Each of the RCTs below compare restrictive vs liberal fluid management, with conflicting conclusions.

BRANDSTRUB ET AL (2003)

This multicenter RCT involved 172 patients allocated to either a restricted or a standard intraoperative and postoperative intravenous fluid regimen. The restricted regimen aimed at maintaining preoperative body weight; the standard regimen resembled everyday practice. The primary outcome measures were complications; the secondary measures were death and adverse effects.

Results: The restricted intravenous fluid regimen significantly reduced postoperative complications both by intention-to-treat (33% versus 51%, P = 0.013) and per-protocol (30% versus 56%, P = 0.003) analyses. The numbers of both cardiopulmonary (7% versus 24%, P = 0.007) and tissue-healing complications (16% versus 31%, P = 0.04) were significantly reduced. No patients died in the restricted group compared with 4 deaths in the standard group (0% versus 4.7%, P = 0.12). No harmful adverse effects were observed.

Conclusion: The restricted perioperative intravenous fluid regimen aiming at unchanged body weight reduces complications after elective colorectal resection.

MYLES ET AL (2018)

This international trial randomly assigned 3000 patients who had an increased risk of complications while undergoing major abdominal surgery to receive a restrictive or liberal intravenous-fluid regimen during and up to 24 hours after surgery. The primary outcome was disability-free survival at 1 year. Key secondary outcomes were acute kidney injury at 30 days, renal-replacement therapy at 90 days, and a composite of septic complications, surgical-site infection, or death.

Results: Up to 24 hours after surgery, 1490 patients in the restrictive fluid group had a median intravenous-fluid intake of 3.7 liters, as compared with 6.1 liters in 1493 patients in the liberal fluid group. The rate of disability-free survival at 1 year was 81.9% in the restrictive fluid group and 82.3% in the liberal fluid group. The rate of AKI was 8.6% in the restrictive fluid group and 5.0% in the liberal fluid group. The rate of septic complications or death was 21.8% in the restrictive fluid group and 19.8% in the liberal fluid group; rates of surgical-site infection (16.5% vs. 13.6%) and renal-replacement therapy (0.9% vs. 0.3%) were higher in the restrictive fluid group, but the between-group difference was not significant after adjustment for multiple testing.

Conclusion: Among patients at increased risk for complications during major abdominal surgery, a restrictive fluid regimen was not associated with a higher rate of disability-free survival than a liberal fluid regimen and was associated with a higher rate of acute kidney injury.

Additional Reading: Romagnoli S, Ricci Z, Ronco C. Perioperative acute kidney injury: prevention, early recognition, and supportive measures. Nephron. 2018;140(2):105-110.

Salmasi V, et al. Relationship between intraoperative hypotension, defined by either reduction from baseline or absolute thresholds, and acute kidney and myocardial injury after noncardiac surgery: a retrospective cohort analysis. Anesthesiology. 2017;126:47-65. doi:10.1097/ALN.0000000000001432

OpenAnesthesia. Encyclopedia: Fluid Management. OpenAnesthesia. 2019. International Anesthesia Research Society. Retrieved from: http://www.openanesthesia.org/fluid-management/

EAST guidelines on the use of antibiotics in thoracostomy

Posted on by
Reply

One discussion this week involved the use of antibiotics in thoracostomy.

Reference: Moore FO et al. Presumptive antibiotic use in tube thoracostomy for traumatic hemopneumothorax: An Eastern Association for the Surgery of Trauma practice management guideline. 2012. Retrieved from: https://www.east.org/education/practice-management-guidelines/tube-thoracostomy-presumptive-antibiotics-in

Summary:  A systematic review was done by 10 acute care surgeons and one statistician to update the 1998 guidelines for EAST. Routine presumptive antibiotic use to reduce the incidence of empyema and pneumonia in tube thoracostomy (TT) for traumatic hemopneumothorax is controversial. Moore et al (2012) conclude that there is insufficient published evidence to support any recommendation either for or against this practice. The authors further state that “until a large and likely multicenter, randomized, controlled trial can be performed, the routine practice of presumptive antibiotics in TT for chest trauma will remain controversial.”

Additionally, the authors are unable to recommend an optimal duration of antibiotic prophylaxis when antibiotics are administered for traumatic hemopneumothorax because there are insufficient published data to support the routine use of antibiotics.

Additional Reading: Department of Surgical Education, Orlando Regional Medical Center. Chest Tube Management. 2016 Sept 8. Retrieved from http://www.surgicalcriticalcare.net/Guidelines/Chest%20tube%20management%202016.pdf

AHA Guidelines on post-cardiac stent operations: post-stent dual antiplatelet therapy (DAPT)

Posted on by
Reply

One discussion last week included the AHA guidelines on post-stent DAPT.

Reference: Levine GN, et al. ACC/AHA Guideline Update on Duration of Dual Antiplatelet Therapy in CAD Patients. American College of Cardiology. Retrieved from https://www.acc.org/latest-in-cardiology/ten-points-to-remember/2016/03/25/14/56/2016-acc-aha-guideline-focused-update-on-duration-of-dapt.

Additional Reading: Capodanno D, et al. ACC/AHA versus ESC guidelines on dual antiplatelet therapy: JACC guideline comparison. Journal of the American College of Cardiology. 2018 Dec 11;72(23 Part A):2915-2931.  doi: 10.1016/j.jacc.2018.09.057.

Summary: Published on the website in March 2016, the following are “key points to remember about the updated guideline on duration of dual antiplatelet therapy (DAPT) in patients with coronary artery disease (CAD)”.

  1. The scope of this focused update is limited to addressing recommendations on duration of DAPT (aspirin plus a P2Y12 inhibitor) in patients with coronary artery disease (CAD).
  2. Intensification of antiplatelet therapy, with the addition of a P2Y12 inhibitor to aspirin monotherapy, and prolongation of DAPT, necessitate a fundamental tradeoff between decreasing ischemic risk and increasing bleeding risk. Decisions regarding treatment with and duration of DAPT require a thoughtful assessment of the benefit/risk ratio, integration of study data, and patient preference.
  3. Recommendations in the document apply specifically to duration of P2Y12 inhibitor therapy in patients with CAD treated with DAPT. Aspirin therapy should almost always be continued indefinitely in patients with CAD.
  4. Lower daily doses of aspirin, including in patients treated with DAPT, are associated with lower bleeding complications and comparable ischemic protection compared with higher doses of aspirin. The recommended daily dose of aspirin in patients treated with DAPT is 81 mg (range 75–100 mg).
  5. In patients with stable ischemic heart disease (SIHD) treated with DAPT after drug-eluting stent (DES) implantation, P2Y12 inhibitor therapy with clopidogrel should be given for at least 6 months (Class I). In patients with SIHD treated with DAPT after bare-metal stent (BMS) implantation, P2Y12 inhibitor therapy (clopidogrel) should be given for a minimum of 1 month (Class I).
  6. In patients with SIHD treated with DAPT after BMS or DES implantation who have tolerated DAPT without a bleeding complication and who are not at high bleeding risk (e.g., prior bleeding on DAPT, coagulopathy, oral anticoagulant use), continuation of DAPT with clopidogrel for longer than 1 month in patients treated with BMS or longer than 6 months in patients treated with DES may be reasonable (Class IIb).
  7. In patients with acute coronary syndrome (ACS) (non-ST elevation [NSTE]-ACS or ST elevation myocardial infarction [STEMI]) treated with DAPT after BMS or DES implantation, P2Y12 inhibitor therapy (clopidogrel, prasugrel, or ticagrelor) should be given for at least 12 months (Class I).
  8. In patients with ACS (NSTE-ACS or STEMI) treated with coronary stent implantation who have tolerated DAPT without a bleeding complication and who are not at high bleeding risk (e.g., prior bleeding on DAPT, coagulopathy, oral anticoagulant use), continuation of DAPT (clopidogrel, prasugrel, or ticagrelor) for longer than 12 months may be reasonable (Class IIb). A new risk score (the “DAPT score”), derived from the Dual Antiplatelet Therapy study, may be useful for decisions about whether to continue (prolong or extend) DAPT in patients treated with coronary stent implantation.
  9. In patients with ACS (NSTE-ACS or STEMI) treated with DAPT after coronary stent implantation and in patients with NSTE-ACS treated with medical therapy alone (without revascularization), it is reasonable to use ticagrelor in preference to clopidogrel for maintenance P2Y12 inhibitor therapy (Class IIa). Among those who are not at high risk for bleeding complications and who do not have a history of stroke or transient ischemic attack, it is reasonable to choose prasugrel over clopidogrel for maintenance P2Y12 inhibitor therapy (Class IIa).
  10. In patients with ACS (NSTE-ACS or STEMI) being treated with DAPT who undergo coronary artery bypass grafting (CABG), P2Y12 inhibitor therapy should be resumed after CABG to complete 12 months of DAPT therapy after ACS (Class I).
  11. In patients with STEMI treated with DAPT in conjunction with fibrinolytic therapy, P2Y12inhibitor therapy (clopidogrel) should be continued for a minimum of 14 days and ideally at least 12 months (Class I).
  12. Elective noncardiac surgery should be delayed 30 days after BMS implantation and optimally 6 months after DES implantation. In patients treated with DAPT after coronary stent implantation who must undergo surgical procedures that mandate the discontinuation of P2Y12 inhibitor therapy, it is recommended that aspirin be continued if possible and the P2Y12 platelet receptor inhibitor be restarted as soon as possible after surgery (Class I).

(Levine et al, 2016)

 

 

AHA Guidelines on post-cardiac stent operations: Perioperative risk assessment

Posted on by
Reply

A discussion last week included the AHA Guidelines for post-cardiac stent operations.

Reference: Fleisher LA, et al. 2014 ACC/AHA Guideline on Perioperative Cardiovascular Evaluation and Management of Patients Undergoing Noncardiac Surgery: Executive Summary: A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation. 2014 Dec 9;130(24):2215-45. doi: 10.1161/CIR.0000000000000105.

Summary: Below are ACC/AHA recommendations on perioperative risk assessment, section 5.2 of the guidelines linked above.

5.2. Timing of Elective Noncardiac Surgery in Patients With Previous PCI

Class I

  1. Elective noncardiac surgery should be delayed 14 days after balloon angioplasty (Level of Evidence: C) and 30 days after BMS implantation. (Level of Evidence B)

  2. Elective noncardiac surgery should optimally be delayed 365 days after drug-eluting stent (DES) implantation.(Level of Evidence: B)

Class IIa

  1. In patients in whom noncardiac surgery is required, a consensus decision among treating clinicians as to the relative risks of surgery and discontinuation or continuation of antiplatelet therapy can be useful. (Level of Evidence: C)

Class IIb

  1. Elective noncardiac surgery after DES implantation may be considered after 180 days if the risk of further delay is greater than the expected risks of ischemia and stent thrombosis. (Level of Evidence: B)

Class III: Harm

  1. Elective noncardiac surgery should not be performed within 30 days after BMS implantation or within 12 months after DES implantation in patients in whom dual antiplatelet therapy will need to be discontinued perioperatively. (Level of Evidence: B)

  2. Elective noncardiac surgery should not be performed within 14 days of balloon angioplasty in patients in whom aspirin will need to be discontinued perioperatively. (Level of Evidence: C)

The role of evoked potentials in thoracoabdominal aortic repair

Posted on by
Reply

One discussion this week involved the role of evoked potentials in thoracoabdominal aortic (TAA) repair.

Reference: Achouh PE, et al. Role of somatosensory evoked potentials in predicting outcome during thoracoabdominal aortic repair. The Annals of Thoracic Surgery. 2007 Sep; 84(3):782-787.

Summary:  Between January 2000 and April 2005, a study out of Houston, TX, used SSEP monitoring in 444 patients (270 thoracoabdominal aorta and 174 descending thoracic aorta).  Changes were classified as (1) no change, (2) transient changes that returned to baseline by the end of the procedure, or (3) persistent changes that did not return to baseline by the end of the procedure.

Primary findings included:

  • Somatosensory evoked potential changes occurred in 87 (19.6%) patients; 22 (25%) of these did not return to baseline.
  • Immediate neurologic deficit occurred in 8 of 444 patients (1.8%); five deficits (5 of 87; 5.8%) occurred in patients with SSEP changes, compared with three deficits (3 of 357; 0.8%) in patients without changes.
  • Somatosensory evoked potential was a poor screening tool for neurologic deficit, with a sensitivity of 62.5% and specificity 81.2%. Negative predictive value was 99.2%, indicating a very low event probability in the absence of SSEP changes. Delayed neurologic deficit occurred in 3.2% and was not related to SSEP changes.
  • Somatosensory evoked potential changes were also associated with increased 30-day mortality and low glomerular filtration rate.

Achouh et al (2007) conclude that “intraoperative SSEP monitoring was reliable in ruling out spinal injury in DTA and TAA repair, but had a low sensitivity. Somatosensory evoked potential did not predict delayed ND. Spinal SSEP change was an independent predictor for mortality in DTA and TAA repair and correlated with low preoperative glomerular filtration rate” (p.787).