Safety of Gastrointestinal Endoscopy With Conscious Sedation in Patients With and Without Obstructive Sleep Apnea.

BACKGROUND AND STUDY AIMS: Patients with obstructive sleep apnea (OSA) undergoing endoscopy with sedation are considered by practitioners to be at a higher risk for cardiopulmonary complications. The aim of the present study was to evaluate the safety of conscious sedation in patients with OSA undergoing gastrointestinal endoscopy. PATIENTS AND METHODS: This is an IRB-approved prospective cohort study performed at the James A. Haley VA. A total of 248 patients with confirmed moderate or severe OSA by polysomnography and 252 patients without OSA were enrolled. Cardiopulmonary variables such as heart rate, blood pressure, and level of blood oxygen saturation were recorded at 3-minute intervals throughout the endoscopic procedure. RESULTS: In total, 302 colonoscopies, 119 esophagogastroduodenoscopies, 6 flexible sigmoidoscopies, and 60 esophagogastroduodenoscopy/colonoscopies were performed. None of the patients in the study required endotracheal intubation, pharmacologic reversal, or experienced an adverse outcome as a result of changes in blood pressure, heart rate, or blood oxygen saturation. There were no significant differences in the rate of tachycardia (P=0.749), bradycardia (P=0.438), hypotension (systolic/diastolic, P=0.460; mean arterial pressure, P=0.571), or hypoxia (P=0.787) between groups. The average length of time spent in each procedure and the average dose of sedation administered also did not differ significantly between the groups. CONCLUSIONS: Despite the presumed increased risk of cardiopulmonary complications, patients with OSA who undergo endoscopy with conscious sedation have clinically insignificant variations in cardiopulmonary parameters that do not differ from those without OSA. Costly preventative measures in patients with OSA are not warranted.

Acute Putrescine Supplementation with Schwann Cell Implantation Improves Sensory and Serotonergic Axon Growth and Functional Recovery in Spinal Cord Injured Rats.

Schwann cell (SC) transplantation exhibits significant potential for spinal cord injury (SCI) repair and its use as a therapeutic modality has now progressed to clinical trials for subacute and chronic human SCI. Although SC implants provide a receptive environment for axonal regrowth and support functional recovery in a number of experimental SCI models, axonal regeneration is largely limited to local systems and the behavioral improvements are modest without additional combinatory approaches. In the current study we investigated whether the concurrent delivery of the polyamine putrescine, started either 30 min or 1 week after SCI, could enhance the efficacy of SCs when implanted subacutely (1 week after injury) into the contused rat spinal cord. Polyamines are ubiquitous organic cations that play an important role in the regulation of the cell cycle, cell division, cytoskeletal organization, and cell differentiation. We show that the combination of putrescine with SCs provides a significant increase in implant size, an enhancement in axonal (sensory and serotonergic) sparing and/or growth, and improved open field locomotion after SCI, as compared to SC implantation alone. These findings demonstrate that polyamine supplementation can augment the effectiveness of SCs when used as a therapeutic approach for subacute SCI repair.

Social and environmental enrichment improves sensory and motor recovery after severe contusive spinal cord injury in the rat.

Neuropathic pain and motor dysfunction are difficult problems following spinal cord injury (SCI). Social and environmental enrichment (SEE), which models much of the clinical rehabilitation environment for post-SCI persons, is the focus of the current investigation which examines the effects of multiple-housing and the addition of climbing spaces, improved bedding and crawl toys on the sensory and motor recovery following a severe contusive SCI. Efficacy was determined with sensory testing, open-field motor behavioral testing, lesion volume analysis and quantification of brain-derived neurotrophic factor (BDNF) in the lumbar spinal cord with and without SEE provided during the recovery period. Sensory and motor testing were performed weekly for 12 weeks following SCI. SEE significantly and permanently reversed cutaneous allodynia, but not thermal hyperalgesia, to near normal levels. The gross locomotor performance (BBB [Basso, Beattie, and Bresnahan] motor scores) significantly improved about two points. In addition, the BBB subscale scores were significantly improved nearly seven points by the end of the study. SEE also significantly improved foot rotation to normal levels and reduced gridwalk footfall errors nearly 50%, but had no effect on stride length or base of support dysfunctions. SEE significantly increased the total volume of a thoracic segment of cord encompassing the injury site at 12 weeks, by reducing cavitation and increasing both the volume of grey and white matter spared, compared to SCI alone. When BDNF levels were examined in the injured lumbar spinal cord, SEE significantly returned BDNF levels to near-normal. These data suggest that immediate use of SEE after contusive SCI is able to improve overall spinal cell survival and prevent much of the sensory and motor dysfunction that accompanies contusive SCI.

Safety of gastrointestinal endoscopy with conscious sedation in obstructive sleep apnea.

AIM: To perform a systematic review and meta-analysis to assess the safety of conscious sedation in patients with obstructive sleep apnea (OSA). METHODS: A comprehensive electronic search of MEDLINE and EMBASE was performed from inception until March 1, 2015. In an effort to include unpublished data, abstracts from prior gastroenterological society meetings as well as other reference sources were interrogated. After study selection, two authors utilizing a standardized data extraction form collected the data independently. Any disagreements between authors were resolved by consensus among four authors. The methodological quality was assessed using the Newcastle Ottawa tool for observational studies. The primary variables of interest included incidence of hypoxia, hypotension, tachycardia, and bradycardia. Continuous data were summarized as odds ratio (OR) and 95%CI and pooled using generic inverse variance under the random-effects model. Heterogeneity between pooled studies was assessed using the I2 statistic. RESULTS: Initial search of MEDLINE and EMBASE identified 357 citations. A search of meeting abstracts did not yield any relevant citations. After systematic review and exclusion consensus meetings, seven studies met the a priori determined inclusion criteria. The overall methodological quality of included studies ranged from moderate to low. No significant differences between OSA patients and controls were identified among any of the study variables: Incidence of hypoxia (7 studies, 3005 patients; OR = 1.11; 95%CI: 0.73-1.11; P = 0.47; I2 = 0%), incidence of hypotension (4 studies, 2125 patients; OR = 1.10; 95%CI: 0.75-1.60; P = 0.63; I2 = 0%), incidence of tachycardia (3 studies, 2030 patients; OR = 0.94; 95%CI: 0.53-1.65; P = 0.28; I2 = 21%), and incidence of bradycardia (3 studies, 2030 patients; OR = 0.88; 95%CI: 0.63-1.22; P = 0.59; I2 = 0%). CONCLUSION: OSA is not a significant risk factor for cardiopulmonary complications in patients undergoing endoscopic procedures with conscious sedation.

Carbon dioxide versus room air insufflation during balloon-assisted enteroscopy: A systematic review with meta-analysis.

Background and study aims Carbon dioxide (CO2) insufflation has been suggested to be an ideal alternative to room air insufflation to reduce trapped air within the bowel lumen after balloon assisted enteroscopy (BAE). We performed a systematic review and meta-analysis to assess the safety and efficacy of utilizing CO2 insufflation as compared to room air during BAE. Patients and methods The primary outcome is mean change in visual analog scale (VAS; 10 cm) at 1, 3, and 6 hours to assess pain. Secondary outcomes include insertion depth (anterograde or retrograde), adverse events, total enteroscopy rate, diagnostic yield, mean anesthetic dosage, and PaCO2 at procedure completion. We searched MEDLINE and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception until May 2015. Multiple independent extractions were performed, the process was executed as per the standards of the Cochrane collaboration. Results Four randomized controlled trials (RCTs) were included in the meta-analysis. VAS at 6 hours favored CO2 over room air (MD 0.13; 95 % CI 0.01, 0.25; p = 0.03). Anterograde insertion depth (cm) was improved in the CO2 group (MD, 58.2; 95 % CI 17.17, 99.23; p = 0.005), with an improvement in total enteroscopy rate in the CO2 group (RR 1.91; 95 % CI 1.20, 3.06; p = 0.007). Mean dose of propofol (mg) favored CO2 compared to air (MD, - 70.53; 95 % CI - 115.07, - 25.98; P = 0.002). There were no differences in adverse events in either group. Conclusions Despite the ability of CO2 to improve insertion depth and decrease amount of anesthesia required, further randomized control trials are needed to determine the agent of choice for insufflation in balloon assisted enteroscopy.

Transplantation of Schwann cells and/or olfactory ensheathing glia into the contused spinal cord: Survival, migration, axon association, and functional recovery.

Schwann cells (SCs) and olfactory ensheathing glia (OEG) have shown promise for spinal cord injury repair. We sought their in vivo identification following transplantation into the contused adult rat spinal cord at 1 week post-injury by: (i) DNA in situ hybridization (ISH) with a Y-chromosome specific probe to identify male transplants in female rats and (ii) lentiviral vector-mediated expression of EGFP. Survival, migration, and axon-glia association were quantified from 3 days to 9 weeks post-transplantation. At 3 weeks after transplantation into the lesion, a 60-90% loss of grafted cells was observed. OEG-only grafts survived very poorly within the lesion (<5%); injection outside the lesion led to a 60% survival rate, implying that the injury milieu was hostile to transplanted cells and or prevented their proliferation. At later times post-grafting, p75(+)/EGFP(-) cells in the lesion outnumbered EGFP(+) cells in all paradigms, evidence of significant host SC infiltration. SCs and OEG injected into the injury failed to migrate from the lesion. Injection of OEG outside of the injury resulted in their migration into the SC-injected injury site, not via normal-appearing host tissue but along the pia or via the central canal. In all paradigms, host axons were seen in association with or ensheathed by transplanted glia. Numerous myelinated axons were found within regions of grafted SCs but not OEG. The current study details the temporal survival, migration, axon association of SCs and OEG, and functional recovery after grafting into the contused spinal cord, research previously complicated due to a lack of quality, long-term markers for cell tracking in vivo.