Intrathecal Morphine in Postoperative Analgesia for Colorectal Cancer Surgery: A Retrospective Study.

BACKGROUND: Colorectal cancer surgery is commonly performed with adequate analgesia essential for patient recovery. This study assessed the effectiveness of intrathecal morphine and patient-controlled analgesia (ITM + PCA) vs patient-controlled analgesia alone (PCA) for postoperative pain management in colorectal cancer surgery. METHODS: This retrospective study extracted and analyzed data covering a 4-year period (2014-2018) from a clinical database with 24- and 48-hour postsurgery follow-up. Primary outcomes included pain scores, median opioid consumption (oral morphine equivalence dose), sedation, nausea and vomiting, and length of admission. Outcomes were analyzed for ITM + PCA vs PCA alone, overall and stratified by laparotomy or laparoscopy procedures. RESULTS: In total, 283 patients were included: ITM + PCA (163) and PCA alone (120). Median opioid consumption in the first 24 hours for ITM + PCA vs PCA alone was lower for laparotomy (-32.7 mg, P<0.001) and laparoscopy (-14.3 mg, P<0.001). Median pain score (worst pain) within the first 24 hours for ITM + PCA vs PCA alone was similar for laparotomy (P>0.05) and lower for laparoscopy (-1 unit, P=0.031). Sedation occurred less frequently for ITM + PCA vs PCA at 24 hours (3.5% vs 11.4%, P=0.031), with nonsignificant reduction at 48 hours (4.8% vs 18.8%, P=0.090) for laparotomy, but with no difference for laparoscopy (P>0.05). Incidence of nausea and vomiting and length of admission were similar for ITM + PCA vs PCA alone for laparotomy or laparoscopy (P>0.05). CONCLUSION: This retrospective study demonstrated that ITM + PCA can achieve similar analgesic effects after laparotomy and laparoscopy colorectal cancer surgery compared with PCA alone while resulting in a reduction of oral opioid consumption and lower incidence of sedation.

Frequent sampling reveals dynamic responses by the transcriptome to routine media replacement in HepG2 cells.

Cultured cell lines are employed extensively for biological research. Large-scale differential gene expression (LSDGE) is being used to study mechanisms of toxicity in such cultures. 'Normal' gene expression dynamics could have a major impact on the design and interpretation of these studies. In order to provide understanding of such dynamics, we investigated LSDGE responses to media replacement in human hepatoblastoma cells (HepG2) using 5-minute sampling frequencies for 6 hours post routine media replacement. Each mRNA transcript was found to exhibit a characteristic 'operating range' based on signal intensity. Following media replacement, which replenishes nutrients (eg, glucose and glutamate) and removes excretory products (eg, lactate), a complex set of gene expression changes was observed. Some transcripts appeared to switch on from a quiescent state to a very active one (eg, CYP1A1), others exhibited 'clocklike' oscillations (eg, asparagine synthetase), or a synchronous burst (chirp) of expression up regulation (eg, timeless). Mathematical analysis (Fourier Transform, Singular Value Decomposition, Wavelets, Phase Analysis) of oscillating expression patterns identified cycle lengths ranging from 11.8 to 210 minutes. There were prominent 36.5- and 17.4-minute cycles, for subsets of genes, and transcript-specific differences in phase angle with respect to these cycles. The functional consequences of these novel observations remain to be determined. It is clear that dense time-course studies provide a valuable approach to the investigation of physiological responses to nutrients, toxicants, and other environmental variables. This research also highlights the need for an understanding of biological dynamics when using cell culture systems. An Excel data file representing individual transcripts from the respective Clontech cDNA arrays referred to in this article is available at http://taylorandfrancis.metapress.com/openurl.asp?genre=journal&issn=0192-6233. Rows represent data for individual transcripts and columns represent the time-points from 0 to 360 minutes. To access this file, click on the issue link for 31(4), then select this article. In order to access the full article online, you must either have an individual subscription or a member subscription accessed through www.toxpath.org.