Comparison of the Effects of Laparoscopic and Open Surgery on Postoperative Acute Kidney Injury in Patients with Colorectal Cancer: Propensity Score Analysis

Postoperative acute kidney injury (AKI) is a serious complication that increases patient morbidity and mortality. However, few studies have evaluated the effect of laparoscopic surgery on postoperative AKI. This study compared the incidence of postoperative AKI between laparoscopic and open surgery in patients with colorectal cancer. This study retrospectively analyzed 3637 patients who underwent colorectal cancer surgery between June 2008 and February 2012. The patients were classified into laparoscopic (n = 987) and open (n = 2650) surgery groups. We performed multivariable regression analysis to assess the risk factors for AKI and propensity score matching analysis to compare the incidence of AKI between the two groups. We also assessed postoperative intensive care unit (ICU) admission, complications, hospital stay, and 1-year mortality. We observed no significant differences in the incidence of postoperative AKI between the two groups before (8.8% vs. 9.1%, p = 0.406) and after (8.8% vs. 7.7%, p = 0.406) matching. Laparoscopic surgery was not associated with AKI even after adjusting for intraoperative variables (adjusted odds ratio (OR): 1.17, 95% confidence interval (CI): 0.84-1.62, p = 0.355). Body mass index, diabetes mellitus, hypertension, and albumin were risk factors for AKI. ICU admission (0.6% vs. 2.5%, p = 0.001), complications (0.2% vs. 1.5%, p = 0.002), hospital stay (6.89 days vs. 8.61 days, p < 0.001), and 1-year mortality (0.1% vs. 0.9%, p = 0.021) were significantly better in the laparoscopic than in the open group. The incidence of postoperative AKI did not differ significantly between laparoscopic and open surgery. However, considering its better surgical outcomes, laparoscopic surgery may be recommended for patients with colorectal cancer

Performance of the Surgical Pleth Index and Analgesia Nociception Index in Healthy Volunteers and Parturients

Various commercially available nociception devices have been developed to quantify intraoperative pain. The Surgical Pleth Index (SPI) and Analgesia Nociception Index (ANI) are among the analgesic indices that have been widely used for the evaluation of surgical patients. This study aimed to evaluate the clinical performance of the SPI and ANI in conscious healthy volunteers and parturients. Ten healthy volunteers and 10 parturients participated in this study. An algometer was used to induce bone pain in the volunteers until they rated their pain as five on the numerical rating scale (NRS); this procedure was repeated during the administration of remifentanil or normal saline. The study comprised two periods, and the volunteers were infused with different solutions in each period: normal saline during one period and remifentanil during the other in a randomized order. The parturients' SPI and ANI data were collected for 2 min when they rated their pain levels as 0, 5, and 7 on the NRS, respectively. Both the SPI and ANI values differed significantly between NRS 0 and NRS 5 (P < 0.001) in the volunteers, irrespective of the solution administered (remifentanil or normal saline). At NRS 5, the SPI showed similar values, irrespective of remifentanil administration, while the ANI showed significantly lower values on remifentanil administration (P = 0.028). The SPI and ANI values at NRS 5 and NRS 7 did not differ significantly in the parturients (P = 0.101 for SPI, P = 0.687 for ANI). Thus, the SPI and ANI were effective indices for detecting pain in healthy volunteers and parturients

Population pharmacokinetic analysis of ropivacaine extended-release from a temperature-responsive hydrogel in rats

Therapeutic agents with a short half-life need to be administered frequently to achieve sustained and effective concentrations. This could be accomplished using sustained drug delivery technology. PF-72 (TGel Bio, Inc., Seoul, Korea) is a drug delivery system based on a powder obtained from lyophilisation of a reverse thermal hydrogel, which could assist in achieving prolonged pain relief if mixed with an anaesthetic and injected into the incision site following surgery. The pharmacokinetic parameters related to the absorption of the local anaesthetic ropivacaine delivered using this hydrogel were quantified. Ten rats were divided into two groups (n = 5 each), and equal doses (4 mg/kg) of different formulations were subcutaneously injected into the abdomen. The experimental group received PF-72 mixed with 0.75% ropivacaine, and the control group received 0.75% ropivacaine. Blood was collected at specific times to measure the plasma concentration of ropivacaine. Population pharmacokinetic analysis was performed using NONMEM VII level 4 (ICON Development Solutions, Dublin, Ireland). The one-compartment absorption model, which combines zero-order absorption and first-order absorption, was used to describe the change in ropivacaine plasma concentration over time. The type of formulation was a significant covariate for zero-order absorption duration (experimental group, 92.9 min; control group, 60.5 min). The addition of PF-72 to 0.75% ropivacaine increased the duration of absorption into the blood, suggesting a longer lasting effect of the analgesic injected into the surgical wound

Association of Preoperative Prognostic Nutritional Index and Postoperative Acute Kidney Injury in Patients with Colorectal Cancer Surgery

The prognostic nutritional index (PNI) has been reported to be associated with postoperative complications and prognosis in cancer surgery. However, few studies have evaluated the association between preoperative PNI and postoperative acute kidney injury (AKI) in colorectal cancer patients. This study evaluated association of preoperative PNI and postoperative AKI in patients who underwent colorectal cancer surgery. This study retrospectively analyzed 3543 patients who underwent colorectal cancer surgery between June 2008 and February 2012. The patients were classified into four groups by the quartile of PNI: Q1 (<= 43.79), Q2 (43.79-47.79), Q3 (47.79-51.62), and Q4 (>= 51.62). Multivariate regression analysis was performed to assess the risk factors for AKI and 1-year mortality. AKI was defined according to Kidney Disease Improving Global Outcomes classification (KDIGO) criteria. Additionally, we assessed surgical outcomes such as hospital stay, ICU admission, and postoperative complications. The incidence of postoperative AKI tended to increase in the Q1 group (13.4%, 9.2%, 9.4%, 8.8%). In the multivariate analysis, high preoperative PNI was significantly associated with low risk of postoperative AKI (adjusted odds ratio [OR]: 0.96, 95% confidence interval [CI]: 0.93-0.99, p = 0.003) and low 1-year mortality (OR: 0.92, 95% CI: 0.86-0.98, p = 0.011). Male sex, body mass index, diabetes mellitus, and hypertension were risk factors for AKI. The Q1 (<= 43.79) group had poor surgical outcomes, such as postoperative AKI (OR: 1.52, 95% CI: 1.18-1.95, p = 0.001), higher rates of ICU admission (OR: 3.13, 95% CI: 1.82-5.39, p < 0.001) and higher overall mortality (OR: 3.81, 95% CI: 1.86-7.79, p < 0.001). In conclusion, low preoperative PNI levels, especially in the Q1 (<= 43.79), were significantly associated with postoperative AKI and surgical outcomes, such as hospital stay, postoperative ICU admission, and mortality

Impact of Sarcopenia on Acute Kidney Injury after Infrarenal Abdominal Aortic Aneurysm Surgery: A Propensity Matching Analysis

Background: Sarcopenia contributes to increased morbidity and mortality in patients undergoing surgery for abdominal aortic aneurysms (AAA). However, few reports have demonstrated whether sarcopenia would affect the development of postoperative acute kidney injury (AKI) in these patients. This study aimed to examine whether sarcopenia is associated with AKI and morbidity and mortality after infrarenal AAA operation. Methods: We retrospectively analysed 379 patients who underwent infrarenal AAA surgery. The diagnosis of sarcopenia was performed using the skeletal muscle index, which was calculated from axial computed tomography at the level of L3. The patients were separated into those with sarcopenia (n = 104) and those without sarcopenia (n = 275). We applied multivariable and Cox regression analyses to evaluate the risk factors for AKI and overall mortality. A propensity score matching (PSM) evaluation was done to assess the postoperative results. Results: The incidence of AKI was greater in sarcopenia than non-sarcopenia group before (34.6% vs. 15.3%; p < 0.001) and after the PSM analysis (34.6% vs. 15.4%; p = 0.002). Multivariable analysis revealed sarcopenia to be associated with AKI before (p = 0.010) and after PSM (p = 0.016). Sarcopenia was also associated with overall mortality before (p = 0.048) and after PSM (p = 0.032). A Kaplan-Meier analysis revealed that overall mortality was elevated patients with sarcopenia before and after PSM than in those without (log-rank test, p < 0.001, p = 0.022). Conclusions: Sarcopenia was associated with increased postoperative AKI incidence and overall mortality among individuals who underwent infrarenal AAA operation

Development of a new pharmacokinetic model for target-concentration controlled infusion of cefoxitin as a prophylactic antibiotic in colorectal surgical patients

Aims: There are several limitations to the existing method of administering cefoxitin as a prophylactic antibiotic, and the limitations may be overcome by applying the target-concentration controlled infusion (TCI) method. Population pharmacokinetic parameters are required to administer cefoxitin by the TCI method. The aim of this study was to construct a new pharmacokinetic model of cefoxitin for the TCI method in colorectal surgical patients Methods: In patients undergoing colorectal surgery, 2 g cefoxitin was dissolved in 50 mL saline and administered for 10 min prior to skin incision. Arterial blood samples were obtained at pre-set intervals to measure the total and free plasma concentrations of cefoxitin. Population pharmacokinetic analysis was performed using the NONMEM software (ICON Development Solutions, Dublin, Ireland). Additionally, the stochastic simulation was used to indirectly evaluate the effectiveness of the two administration methods (standard method vs. TCI) Results: In total, 297 plasma concentration measurements from 31 patients were used to characterize the pharmacokinetics of cefoxitin. A three-compartment mammillary model well-described the pharmacokinetics of cefoxitin. Body weight and creatinine clearance were significant covariates for clearance. The stochastic simulation showed that when compared with the standard method, the TCI method has a significantly higher fraction of time that the free concentration of cefoxitin is maintained above the minimum inhibitory concentration (P < 0.001). Conclusions: TCI has the potential to become a new infusion method for patient-tailored dosing in surgical patients. To administer cefoxitin via TCI in clinical practice, the newly constructed pharmacokinetic model should undergo proper external validation