Cerebral Autoregulation Real-Time Monitoring.

Cerebral autoregulation is a mechanism which maintains constant cerebral blood flow (CBF) despite changes in mean arterial pressure (MAP). Assessing whether this mechanism is intact or impaired and determining its boundaries is important in many clinical settings, where primary or secondary injuries to the brain may occur. Herein we describe the development of a new ultrasound tagged near infra red light monitor which tracks CBF trends, in parallel, it continuously measures blood pressure and correlates them to produce a real time autoregulation index. Its performance is validated in both in-vitro experiment and a pre-clinical case study. Results suggest that using such a tool, autoregulation boundaries as well as its impairment or functioning can be identified and assessed. It may therefore assist in individualized MAP management to ensure adequate organ perfusion and reduce the risk of postoperative complications, and might play an important role in patient care.

Intraoperative Cerebral Autoregulation Assessment Using Ultrasound-Tagged Near-Infrared-Based Cerebral Blood Flow in Comparison to Transcranial Doppler Cerebral Flow Velocity: A Pilot Study.

OBJECTIVE: This was a pilot study comparing the ability of a new ultrasound-tagged near-infrared (UT-NIR) device to detect cerebral autoregulation (CA) in comparison to transcranial Doppler (TCD). DESIGN: An unblinded, prospective, clinical feasibility study. SETTING: Tertiary-care university hospital cardiac surgical operating rooms. PARTICIPANTS: Twenty adult patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). INTERVENTIONS: There were no clinical interventions based on study monitoring devices, but a continuous correlation analysis of digital data from transcranial Doppler (TCD) velocity was compared with a novel UT-NIR device and correlation analysis of change signals versus mean arterial pressure was performed in order to detect presence or absence of intact CA and for determination of the lower limit of cerebral autoregulation during CPB. MEASUREMENTS AND MAIN RESULTS: Similar and highly significant concordance (κ = 1.00; p<0.001) was demonstrated between the 2 methodologies for determination of CA, indicating good correlation between the 2 methodologies. Intact CA was absent in 2 patients during CPB, and both devices were able to detect this. CONCLUSIONS: To the authors' knowledge this is the first clinical report of a UT-NIR device that shows promise as a clinically useful modality for detection of CA and the lower limit of cerebral autoregulation. The utility of UT-NIR was demonstrated further during times at which extensive usage of electrocautery or functional absence of the transcranial window rendered TCD uninterpretable.

A new technology for detecting cerebral blood flow: a comparative study of ultrasound tagged NIRS and 133Xe-SPECT.

There is a need for real-time non-invasive, continuous monitoring of cerebral blood flow (CBF) during surgery, in intensive care units and clinical research. We investigated a new non-invasive hybrid technology employing ultrasound tagged near infrared spectroscopy (UT-NIRS) that may estimate changes in CBF using a cerebral blood flow index (CFI). Changes over time for UT-NIRS CFI and 133Xenon single photon emission computer tomography (133Xe-SPECT) CBF data were assessed in 10 healthy volunteers after an intravenous bolus of acetazolamide. UT-NIRS CFI was measured continuously and SPECT CBF was measured at baseline, 15 and 60 min after acetazolamide. We found significant changes over time in CFI by UT-NIRS and CBF by SPECT after acetazolamide (P ≤ 0.001). Post hoc tests showed a significant increase in CFI (P = 0.011) and SPECT CBF (P < 0.001) at 15 min after acetazolamide injection. There was a significant correlation between CFI and SPECT CBF values (r = 0.67 and P ≤ 0.033) at 15 min, but not at 60 min (P ≥ 0.777). UT-NIRS detected an increase in CFI following an acetazolamide bolus, which correlated with CBF measured with 133Xe-SPECT. This study demonstrates that UT-NIRS technology may be a promising new technique for non-invasive and real-time bedside CBF monitoring.

A prospective, controlled, randomized, multicenter, exploratory pilot study evaluating the safety and potential trends in efficacy of Adhexil.

OBJECTIVE: To present a multicenter, reviewer-blinded pilot study evaluating the safety and trends of efficacy of Adhexil, a novel product using fibrin sealant. DESIGN: Randomized, reviewer-blinded assessment of postoperative adhesion development in women with bilateral ovarian disease. SETTING: Gynecologic clinics. PATIENT(S): Women undergoing gynecologic surgery. INTERVENTION(S): Patients were assessed for incidence, extent, and severity of ovarian adhesions at the first-look laparoscopy (1LL), followed by standard surgical procedure. Ovaries were randomized for application of Adhexil or untreated. A second-look laparoscopy (2LL) was performed to assess postoperative adhesions. MAIN OUTCOME MEASURE(S): Safety and efficacy of Adhexil. RESULT(S): A trend toward improvement in adhesion incidence was found in the treated ovaries, with 50% (8/16) of adhesion free ovaries in the Adhexil group, versus 31% (5/16) of control ovaries. Similarly, the improvement in the mean American Fertility Society (AFS) score in the Adhexil-treated group from 1LL (6.4 ± 6.8) to 2LL (4.6 ± 6.9) was observed, whereas worsening of adhesions was observed on the control side from 1LL (5.6 ± 5.1) to 2LL (7.1 ± 6.9). No adverse events or serious adverse events considered related to the study product were reported. CONCLUSION(S): A clear trend of efficacy for Adhexil reducing the incidence, severity, and extend of adhesions in laparoscopic gynecology surgery, despite the small sample size. The use of Adhexil appears safe. Further exploration of its safety and efficacy in preventing/reducing postsurgical adhesions is warranted.

Adhesion prevention and reduction: current status and future recommendations of a multinational interdisciplinary consensus conference.

Adhesions can be found after virtually every abdominopelvic operation performed through standard laparotomy as well as by laparoscopic approaches. Adhesions can be completely asymptomatic or can cause significant morbidity and mortality including strangulation, obstruction, and necrosis of bowel loops and/or infertility and organ injury during repeat abdominal surgery. Perhaps because of the multifactorial nature of adhesion development, prevention has been very limited. Three anti-adhesion products are commercially available, none of which has been universally accepted as a panacea. Part of the obstacles with adhesion management is the lack of an objective clinically relevant classification to allow their study. Because a single band can cause a life-threatening bowel obstruction, whereas extensive dense intra-abdominal adhesions may be asymptomatic, neither the mere presence or absence of adhesions nor their extent if present is totally adequate endpoints. Adhesions are a major health care burden, and their reduction is a significant unmet need in surgical therapeutics facing all surgeons. Of all the parameters assessing adhesions currently available, the authors believe that adhesion incidence (presence or absence) is the most relevant endpoint with a direct clinical implication. The authors endorse the development of a validated, clinically relevant scale to assess intra-abdominal adhesions. Given the present limitation of objective assessment of adhesions and prediction of their clinical effect, the authors also advocate, when appropriate, the use of one of the Food and Drug Administration-approved adhesion barriers. Further research is required to develop safe and effective anti-adhesion methods as well as better assessment tools for their efficacy.

Actual colonic perforation in virtual colonoscopy: report of a case.

Computed tomography colonography, also termed virtual colonoscopy, is a new imaging method to investigate the colon, which may be a potential alternative to the conventional endoscopic colonoscopy in some cases. The high safety profile of this imaging method was considered as an additional advantage of this procedure. A case of colonic perforation in computed tomography colonography is presented, highlighting a potential risk related to this procedure. It is assumed that perforation was the result of overinflation of air into an obstructed colon caused by a lesion at the rectosigmoid junction. Thus, it is suggested that in such cases, air insufflation should be gradual, thereby minimizing the risk of perforation.

Small bowel obstruction from a dislodged feeding tube.

Elderly nursing home patients may suffer from inadequate oral nutritional intake for a variety of reasons. In some of them, nutritional status cannot be maintained without the use of enteral feeding. Nasogastric tube feeding is associated with significant patient discomfort, and may lead to significant complications. Thus, in those who require long-term enteral tube feeding, a gastrostomy tube may be necessary. Although surgical insertion may occasionally be required, percutaneous insertion with upper endoscopy assistance is usually safe and feasible. This case represents an unusual complication of such a gastrostomy tube, which draws attention to the need for appropriate care of these tubes.