Effects of ischemic conditioning on head and neck free flap oxygenation: a randomized controlled trial.

Flap failure after microvascular reconstructive surgery is a rare but devastating complication caused by reperfusion injury and tissue hypoperfusion. Remote ischemic conditioning (RIC) provides protection against ischemia/reperfusion injury and reduces tissue infarction. We hypothesized that RIC would enhance flap oxygenation and exert organ-protective effects during head and neck free flap reconstructive surgery. Adult patients undergoing free flap transfer surgery for head and neck cancer were randomized to receive either RIC or sham-RIC during surgery. RIC consisted of four cycles of 5-min ischemia and 5-min reperfusion applied to the upper or lower extremity. The primary endpoint, tissue oxygen saturation of the flap, was measured by near-infrared spectroscopy on the first postoperative day. Organ-protective effects of RIC were evaluated with infarct size of rat hearts perfused with plasma dialysate from patients received RIC or sham-RIC. Between April 2018 and July 2019, 50 patients were randomized (each n = 25) and 46 were analyzed in the RIC (n = 23) or sham-RIC (n = 23) groups. Tissue oxygen saturation of the flap was similar between the groups (85 ± 12% vs 83 ± 9% in the RIC vs sham-RIC groups; P = 0.471). Myocardial infarct size after treatment of plasma dialysate was significantly reduced in the RIC group (44 ± 7% to 26 ± 6%; P = 0.018) compared to the sham-RIC group (42 ± 6% to 37 ± 7%; P = 0.388). RIC did not improve tissue oxygenation of the transferred free flap in head and neck cancer reconstructive surgery. However, there was evidence of organ-protective effects of RIC in experimental models.Trial registration: Registry number of ClinicalTrials.gov: NCT03474952.

Intraarterial catheter diameter and dynamic response of arterial pressure monitoring system: a randomized controlled trial.

The dynamic response (DR) of the arterial pressure monitoring system (APMS) may depend on the intraarterial catheter (IAC) diameter. We hypothesized that adequate DR would be more common when using a smaller IAC. We compared the DR of the AMPS (Auto Transducer™) between three IACs (BD Angiocath Plus™) with different diameters. 353 neurosurgical patients were randomized into three groups undergoing catheterization with a 20-, 22-, or 24-gauge IAC: 20G (n = 119), 22G (n = 117), and 24G (n = 117) groups, respectively. The DR, which depends on the natural frequency and damping coefficient, was divided into four types: adequate (primary outcome measure), underdamped, overdamped, and unacceptable. The frequency of intraoperative IAC malfunction was noted. Adequate DR was observed more frequently in the 22G and 24G groups than the 20G group (13.7% and 15.4% vs. 4.2%, P = 0.011 and 0.004, respectively). The frequency of underdamped DR was higher in the 20G group than the 24G group (86.6% vs. 69.2%, P = 0.001), whereas overdamped DR was more frequent in the 24G group than the 20G and 22G groups (6.0% vs. 0.0% and 0.0%, P = 0.007 and 0.014, respectively). IAC malfunctioned more frequently during surgery in the 24G group than the 20G and 22G groups (15.4% vs. 0.0% and 1.7%, P < 0.001 and P < 0.001, respectively). The frequency of adequate DR was low regardless of the IAC diameter. Nonetheless, in terms of DR and IAC malfunction, a 22-gauge BD Angiocath Plus™ was more suitable for invasive blood pressure monitoring with Auto Transducer™ than a 20- or 24-gauge BD Angiocath Plus™. Registration Registry: ClinicalTrials.gov. Registration number: NCT03642756. Date of Registration: July 27, 2018.

Healthcare Resource Utilization After Living Liver Donation: A Retrospective Case-Control Study.

BACKGROUND: Living liver donation is generally considered safe, but donors may experience short- or long-term complications. The purpose of this study was to assess healthcare resource utilization after liver donation in living liver donors in comparison with the general population. METHODS: Outpatient or emergency department visits and hospital admissions were compared between living liver donors who underwent hepatic resection for living liver donation between 2004 and 2018 and the matched general population. Healthcare resource utilization data for 5 y after liver donation were collected from the National Health Insurance Service database. For every living liver donor, 4 individually matched nondonors were selected from the National Health Insurance Service database using age, sex, preexisting comorbidities, and previous healthcare utilization history. RESULTS: A total of 1886 living liver donors and 7309 nondonors were included. In the first year after donation, living liver donors required more outpatient department visits (7 [4-13] versus 3 [1-7], P < 0.001) and more emergency department visits (13.33% versus 0.15%, P < 0.001) compared with matched nondonors. A similar trend persisted for 5 y after donation. The number of hospital admissions of living liver donors was higher for up to 2 y after donation with longer hospital length of stay (13.0 [10.5-16.0] d versus 5.0 [3.0-9.0] d, P < 0.0001). CONCLUSIONS: Healthcare resource utilization in living liver donors for 5 y after donation was higher compared with matched nondonors. The higher healthcare resource demand may be related to postoperative complications or lowered threshold for healthcare resource utilization after donation.

Perioperative ABO Blood Group Isoagglutinin Titer and the Risk of Acute Kidney Injury after ABO-Incompatible Living Donor Liver Transplantation.

For ABO-incompatible liver transplantation (ABO-i LT), therapeutic plasma exchange (TPE) is performed preoperatively to reduce the isoagglutinin titer of anti-ABO blood type antibodies. We evaluated whether perioperative high isoagglutinin titer is associated with postoperative risk of acute kidney injury (AKI). In 130 cases of ABO-i LT, we collected immunoglobulin (Ig) G and Ig M isoagglutinin titers of baseline, pre-LT, and postoperative peak values. These values were compared between the patients with and without postoperative AKI. Multivariable logistic regression analysis was used to evaluate the association between perioperative isoagglutinin titers and postoperative AKI. Clinical and graft-related outcomes were compared between high and low baseline and postoperative peak isoagglutinin groups. The incidence of AKI was 42.3%. Preoperative baseline and postoperative peak isoagglutinin titers of both Ig M and Ig G were significantly higher in the patients with AKI than those without AKI. Multivariable logistic regression analysis showed that preoperative baseline and postoperative peak Ig M isoagglutinin titers were significantly associated with the risk of AKI (baseline: odds ratio 1.06, 95% confidence interval 1.02 to 1.09; postoperative peak: odds ratio 1.08, 95% confidence interval 1.04 to 1.13). Cubic spline function curves show a positive relationship between the baseline and postoperative peak isoagglutinin titers and the risk of AKI. Clinical outcomes other than AKI were not significantly different according to the baseline and postoperative peak isoagglutinin titers. Preoperative high initial and postoperative peak Ig M isoagglutinin titers were significantly associated with the development of AKI. As the causal relationship between high isoagglutinin titers and risk of AKI is unclear, the high baseline and postoperative isoagglutinin titers could be used simply as a warning sign for the risk of AKI after liver transplantation.

Severity and Duration of Acute Kidney Injury and Chronic Kidney Disease after Cardiac Surgery.

We aimed to evaluate whether the duration and stage of acute kidney injury (AKI) are associated with the occurrence of chronic kidney disease (CKD) in patients undergoing cardiac or thoracic aortic surgery. A total of 2009 cases were reviewed. The patients with postoperative AKI stage 1 and higher stage were divided into transient (serum creatinine elevation ≤48 h) or persistent (>48 h) AKI, respectively. Estimated glomerular filtration rate (eGFR) values during three years after surgery were collected. Occurrence of new-onset CKD stage 3 or higher or all-cause mortality was determined as the primary outcome. Multivariable Cox regression and Kaplan-Meier survival analysis were performed. The Median follow-up of renal function after surgery was 32 months. The cumulative incidences of our primary outcome at one, two, and three years after surgery were 19.8, 23.7, and 26.1%. There was a graded significant association of AKI with new-onset CKD during three years after surgery, except for transient stage 1 AKI (persistent stage 1: HR 3.11, 95% CI 2.62-4.91; transient higher stage: HR 4.07, 95% CI 2.98-6.11; persistent higher stage: HR 13.36, 95% CI 8.22-18.72). There was a significant difference in survival between transient and persistent AKI at the same stage. During three years after cardiac surgery, there was a significant and graded association between AKI stages and the development of new-onset CKD, except for transient stage 1 AKI. This association was stronger when AKI lasted more than 48 h at the same stage. Both duration and severity of AKI provide prognostic value to predict the development of CKD.

Pre-emptive epidural analgesia for acute and chronic post-thoracotomy pain in adults: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: Epidural analgesia is the gold standard for post-thoracotomy pain management and can be started before or after surgical incision. This systematic review and meta-analysis investigated whether pre-emptive epidural analgesia before thoracotomy incision reduces acute and chronic post-thoracotomy pain in adults compared with epidural analgesia after incision. METHODS: We searched databases including MEDLINE, Embase, and CENTRAL for randomized controlled trials comparing epidural analgesia initiated before (pre-emptive group) and after (control group) thoracotomy incision in adults. The primary outcomes were the pain intensity during rest and coughing within 72 hours after surgery and the incidence of pain 1 to 6 months after surgery. Data were combined with random-effects meta-analyses. We rated the quality of evidence as high, moderate, low, and very low using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) method. RESULTS: We included 19 trials with 1062 participants involving 529 in the pre-emptive group and 533 in the control group. The pain intensity was significantly lower at rest within 72 hours after surgery (19 studies, n=1062) and during coughing within 48 hours after surgery (11 studies, n=638), and the incidence of pain was significantly lower 1 to 6 months after surgery (6 studies, n=276) in the pre-emptive group than in the control group. The quality of evidence was moderate or low in the primary outcomes. CONCLUSIONS: Our review provides low-quality evidence that pre-emptive epidural analgesia reduces the intensity of acute pain and the incidence of chronic pain after thoracotomy in adults. PROTOCOL REGISTRATION NUMBER: CRD42019131620.