Regional analgesia and surgical site infections after colorectal surgery: a retrospective cohort analysis

Abstract Background The effect of regional analgesia on perioperative infectious complications remains unknown. We therefore tested the hypothesis that a composite of serious infections after colorectal surgery is less common in patients with regional analgesia than in those given Intravenous Patient-Controlled Analgesia (IV-PCA) with opiates. Methods Patients undergoing elective colorectal surgery lasting one hour or more under general anesthesia at the Cleveland Clinic Main Campus between 2009 and 2015 were included in this retrospective analysis. Exposures were defined as regional postoperative analgesia with epidurals or Transversus Abdominis Plane blocks (TAP); or IV-PCA with opiates only. The outcome was defined as a composite of in-hospital serious infections, including intraabdominal abscess, pelvic abscess, deep or organ-space Surgical Site Infection (SSI), clostridium difficile, pneumonia, or sepsis. Logistic regression model adjusted for the imbalanced potential confounding factors among the subset of matched surgeries was used to report the odds ratios along with 95% confidence limits. The significance criterion was p < 0.05. Results A total of 7811 patients met inclusion and exclusion criteria of which we successfully matched 681 regional anesthesia patients to 2862 IV-PCA only patients based on propensity scores derived from potential confounding factors. There were 82 (12%) in-hospital postoperative serious infections in the regional analgesia group vs. 285 (10%) in IV-PCA patients. Regional analgesia was not significantly associated with serious infection (odds ratio: 1.14; 95% Confidence Interval 0.87‒1.49; p-value = 0.339) after adjusting for surgical duration and volume of intraoperative crystalloids. Conclusion Regional analgesia should not be selected as postoperative analgesic technique to reduce infections.

Regional analgesia and surgical site infections after colorectal surgery: a retrospective cohort analysis.

BACKGROUND: The effect of regional analgesia on perioperative infectious complications remains unknown. We therefore tested the hypothesis that a composite of serious infections after colorectal surgery is less common in patients with regional analgesia than in those given Intravenous Patient-Controlled Analgesia (IV-PCA) with opiates. METHODS: Patients undergoing elective colorectal surgery lasting one hour or more under general anesthesia at the Cleveland Clinic Main Campus between 2009 and 2015 were included in this retrospective analysis. Exposures were defined as regional postoperative analgesia with epidurals or Transversus Abdominis Plane blocks (TAP); or IV-PCA with opiates only. The outcome was defined as a composite of in-hospital serious infections, including intraabdominal abscess, pelvic abscess, deep or organ-space Surgical Site Infection (SSI), clostridium difficile, pneumonia, or sepsis. Logistic regression model adjusted for the imbalanced potential confounding factors among the subset of matched surgeries was used to report the odds ratios along with 95% confidence limits. The significance criterion was p < 0.05. RESULTS: A total of 7811 patients met inclusion and exclusion criteria of which we successfully matched 681 regional anesthesia patients to 2862 IV-PCA only patients based on propensity scores derived from potential confounding factors. There were 82 (12%) in-hospital postoperative serious infections in the regional analgesia group vs. 285 (10%) in IV-PCA patients. Regional analgesia was not significantly associated with serious infection (odds ratio: 1.14; 95% Confidence Interval 0.87‒1.49; p-value = 0.339) after adjusting for surgical duration and volume of intraoperative crystalloids. CONCLUSION: Regional analgesia should not be selected as postoperative analgesic technique to reduce infections.

Point-of-Care Ultrasound to Identify Landmarks of the Proximal Humerus: Potential Use for Intraosseous Vascular Access.

OBJECTIVES: The inability to identify landmarks is an absolute contraindication for intraosseous access. The feasibility of landmark identification using ultrasound (US) has been demonstrated on human cadavers. We aimed to study the feasibility of point-of-care US in identifying proximal humerus landmarks in living human patients. METHODS: This was a prospective cohort study conducted from May 3 to June 7, 2017, after approval from the Institutional Review Board at the Cleveland Clinic. Sixty upper extremities of 30 consenting participants across 3 distinct body mass index (BMI) groups (normal, obese, and morbidly obese) were alternately examined with a 12 L-RS linear US transducer (GE Healthcare, Chicago, IL) by 2 investigators. Six anatomic landmarks were identified: the humeral shaft, the surgical neck of the humerus, the lesser tubercle, the greater tubercle, the inter tubercular sulcus, and the target site for needle insertion on the greater tubercle. Rates of successful identification of all 6 landmarks as defined by independent agreement between the investigators were reported as estimated incidence rates with 95% bootstrap confidence interval (CI) sampling at the participant level. RESULTS: Ultrasound had an overall success rate of 0.87 (95% CI, 0.78-0.95) in identifying all 6 landmarks with slight variability among various BMI groups. After excluding the surgical neck, the overall success rate improved to 0.93 (95% CI, 0.87-0.98), with minimum variability across BMI groups and no change in the ability to identify the target site. CONCLUSIONS: Ultrasound is reliable in identifying proximal humerus intraosseous landmarks, with reasonable accuracy across various BMI groups.

Acute Postoperative Pain Is Associated With Myocardial Injury After Noncardiac Surgery.

BACKGROUND: Uncontrolled pain after noncardiac surgery activates the sympathetic nervous system, which causes tachycardia, hypertension, and increased cardiac contractility-all of which may increase myocardial oxygen demand. We therefore determined whether time-weighted average pain scores over the initial 72 postoperative hours are associated with myocardial injury after noncardiac surgery (MINS). METHODS: We conducted a retrospective cohort analysis of adults with routine postoperative troponin monitoring after noncardiac surgery under general, regional, or combined anesthesia at tertiary level centers in Cleveland from January 2012 to December 2015. Time-weighted average pain scores were calculated from all the available pain scores, typically at 4-hour intervals, until a troponin elevation was detected. MINS was defined as peak troponin T concentrations exceeding 0.03 ng/mL within 72 hours after surgery. We used a generalized linear mixed model to assess the association between pain and MINS with 3 hospitals as clusters, adjusting for potential confounders. RESULTS: Among 2892 eligible patients, 4.5% had myocardial injury within 72 hours after surgery. Higher time-weighted average pain scores were associated with increased hazard of myocardial injury. The estimated hazard ratio for a 1-unit increase in pain score was 1.12 (95% confidence interval [CI], 1.02-1.22; P = .013), adjusting for confounding variables. CONCLUSIONS: Among patients undergoing noncardiac surgery, time-weighted average pain scores within 72 hours after surgery were significantly associated with myocardial injury.

Comparing two posterior quadratus lumborum block approaches with low thoracic erector spinae plane block: an anatomic study.

BACKGROUND AND OBJECTIVES: Both posterior quadratus lumborum (QL) and erector spinae plane (ESP) blocks have been described as new truncal interfascial plane blocks. Distribution of injectate is influenced by fascial anatomy; therefore, different injection sites may produce similar spread. This anatomic study was designed to test the hypothesis that a posteromedial QL block at L2 level will more closely resemble a low thoracic ESP block when compared with the posterolateral approach at L2 level. METHODS: Left-sided ESP blocks were performed in six cadavers at T10-11. Three of these cadavers received right-sided posteromedial QL block at L2, while the other three received right-sided posterolateral QL block at L2. All injections were composed of 20 mL methylcellulose 0.5 % mixed with India ink and 10 mL of Omnipaque (Iohexol) 240 mg/mL. CT 24 hours after injection and cadaver dissection were used to evaluate injectate spread. RESULTS: Cephalocaudal spread of injectate by CT and cadaveric dissection was highly correlated (r=0.85 [95% CI 0.51 to 0.95]). Cadaver dissection showed ESP injectate spread deep to the muscle (mean [SD]) 11.7 (2.3) levels compared with 7.3 (1.2) levels for posterolateral QL and 9.7 (1.5) for posteromedial QL (p=0.04 overall, with a statistically significant pairwise difference between ESP and posterolateral QL only). The subcostal nerve and dorsal rami were commonly involved in most blocks, but the paravertebral space and ventral rami had inconsistent involvement. The lumbocostal ligament limited cranial spread from the posterlateral QL block approach. CONCLUSIONS: The posteromedial QL block at L2 produces more cranial spread beyond the lumbocostal ligament than the posterolateral QL block, and this spread is comparable with a low thoracic ESP block. Both posterior QL and ESP blocks show unreliable spread of injectate to the paravertebral space and ventral rami, but the dorsal rami were frequently covered.

A Randomized Trial of Continuous Noninvasive Blood Pressure Monitoring During Noncardiac Surgery.

BACKGROUND: Intraoperative hypotension is associated with postoperative mortality. Early detection of hypotension by continuous hemodynamic monitoring might prompt timely therapy, thereby reducing intraoperative hypotension. We tested the hypothesis that continuous noninvasive blood pressure monitoring reduces intraoperative hypotension. METHODS: Patients ≥45 years old with American Society of Anesthesiologists physical status III or IV having moderate-to-high-risk noncardiac surgery with general anesthesia were included. All participating patients had continuous noninvasive hemodynamic monitoring using a finger cuff (ClearSight, Edwards Lifesciences, Irvine, CA) and a standard oscillometric cuff. In half the patients, randomly assigned, clinicians were blinded to the continuous values, whereas the others (unblinded) had access to continuous blood pressure readings. Continuous pressures in both groups were used for analysis. Time-weighted average for mean arterial pressure <65 mm Hg was compared using 2-sample Wilcoxon rank-sum tests and Hodges Lehmann estimation of location shift with corresponding asymptotic 95% CI. RESULTS: Among 320 randomized patients, 316 were included in the intention-to-treat analysis. With 158 patients in each group, those assigned to continuous blood pressure monitoring had significantly lower time-weighted average mean arterial pressure <65 mm Hg, 0.05 [0.00, 0.22] mm Hg, versus intermittent blood pressure monitoring, 0.11 [0.00, 0.54] mm Hg (P = .039, significance criteria P < .048). CONCLUSIONS: Continuous noninvasive hemodynamic monitoring nearly halved the amount of intraoperative hypotension. Hypotension reduction with continuous monitoring, while statistically significant, is currently of uncertain clinical importance.

Management of Severe Pancreaticoduodenal Injuries.

Severe pancreaticoduodenal injuries are rare and no surgeon and institute get enough number of cases to acquire expertise. Hence, the management of such injuries remains controversial. We report a case of 28 years male who sustained a severe pancreaticoduodenal injury and was managed with emergency pancreaticoduodenectomy with immediate reconstruction. Various approaches have been described in literature with variable outcome. Damage control strategy seems to be most useful approach and major resection should be a part of debridement whenever required. Immediate reconstruction can be carried out safely if patients remain hemodynamically and metabolically stable.