Laser speckle contrast imaging of forehead cutaneous blood flow during carotid endarterectomy as a potential non-invasive method for surrogate monitoring of cerebral perfusion.

Monitoring cerebral perfusion is important for goal-directed anesthesia. Taking advantage of the supply of the supraorbital region and Glabella from the internal carotid artery (ICA), we evaluated changes in cutaneous blood flow using laser speckle contrast imagining (LSCI) as a potential method for indirect real-time monitoring of cerebral perfusion. Nine patients (8 men, mean age 70 years) underwent eversion carotid endarterectomy under local anesthesia. Cutaneous blood flow of the forehead was monitored using LSCI. During clamping of the common carotid artery (CCA), ipsilateral supraorbital region and Glabellas cutaneous blood flow dropped from 334 ± 135 to 221 ± 109 AU (p = 0.023) (AU: arbitrary flux units) and from 384 ± 151 to 276 ± 107 AU (p = 0.023), respectively, whilst the contralateral supraorbital region cutaneous blood flow remained unchanged. The supraorbital cutaneous blood flow did not change significantly following reperfusion of the external carotid artery (ECA) (221 ± 109 to 281 ± 154 AU; p = 0.175) and ICA (281 ± 154 to 310 ± 184 AU; p = 01). A comparable trend for Glabella followed ECA (276 ± 107 to 342 ± 170 AU; p = 0.404) and ICA (342 ± 170 to 352 ± 191 AU; p = 01) reperfusion. In patients undergoing carotid endarterectomy under local anesthesia, LSCI of the supraorbital and Glabella regions reflected clamping of the CCA but did not distinguish reperfusion of the ICA from that of the ECA.

Carbon monoxide reduces near-infrared spectroscopy determined 'total' hemoglobin: a human volunteer study.

Carbon monoxide (CO) increases middle cerebral artery mean flow velocity (MCAVmean), but the effect of CO on the near-infrared spectroscopy (NIRS) determined cerebral oxygenation (ScO2) is not detailed. In our study, 11 non-smoking subjects breathed 100% O2 through a closed circuit. A CO2 scrubber with CO (1.5 mL kg-1) was added to the circuit. Two NIRS systems (NIRO-200NX and INVOS-5100) assessed ScO2 as the ratio of oxygenated to deoxygenated hemoglobin, while venous blood samples were analyzed for carboxyhemoglobin (COHb). After CO/O2 rebreathing COHb increased to 8.7% (IQR; 7.9-9.4; p = .004) vs. normoxia, but MCAVmean remained stable (55.6 cm s-1; 53.1-69.7) compared to inhalation of O2 (54.6 cm s-1; 48.4-62.9; p = .178) and normoxia (54.1 cm s-1; 44.5-66.9; p = .055). Also, INVOS-5100 determined ScO2 increased during CO/O2 (74.4 ± 7.5%) and O2 inhalation (73.1 ± 7.2%) compared to normoxia (68.9 ± 6.9%; p < .001). In contrast, NIRO-200NX determined ScO2 remained unchanged during CO/O2 and O2 inhalations but oxygenated and deoxygenated hemoglobin decreased (by 19.7 µM (median; IQR 2.8-34.8; p = .016) and 37.3 µM (30.8-46.6; p = .004), respectively) during inhalation of CO/O2 compared to inhalation of O2. Therefore, NIRO-200NX determined 'total' hemoglobin (sum of O2Hb and HHb) decreased (by 62.1 µM; 44.5-78.2; p = .001). In conclusion, exposure to CO did not increase MCAVmean, and neither NIRO-200NX nor INVOS-5100 detected a change in ScO2 when CO was added to inhalation of oxygen. Unaffected ScO2 after exposure to CO reflected a similar decrease in oxygenated and deoxygenated hemoglobin suggesting that detection of exposure to CO by NIRS should focus on 'total' hemoglobin rather than on ScO2.

High Parenteral Support Volume Is Associated With Reduced Quality of Life Determined by the Short-Bowel Syndrome Quality of Life Scale in Nonmalignant Intestinal Failure Patients.

BACKGROUND: Aim was to investigate the association between quality of life (QoL), bowel anatomy, and the need for home parenteral support (HPS) volume in patients with nonmalignant short-bowel syndrome (SBS) and intestinal failure (IF). METHODS: The SBS-QoL scale was used in a cross-sectional study of 95 nonmalignant SBS-IF patients. Sum QoL scores (0: best, 170: worst) were calculated. Patients were defined as having a small bowel (≤200 cm), and patients with jejunostomy or ileostomy were subclassified based on functional small-bowel length (cm) into 4 anatomy subgroups: 1a-1d (0-49, 50-99, 100-149, 150-200 cm, respectively). Multiple linear regression analyses explored associations between QoL, patient groups, and HPS volume, adjusting for age, sex, body mass index, and education. RESULTS: Complete data were obtained from 60 patients. HPS volume was associated with a worse SBS-QoL score (L/d, ß = 7.91; SE = 3.90; P = .048), but male sex associated with improvement (ß = -26.28; SE = 11.06; P = .021). No differences in sum QoL were seen between the benign SBS-IF subgroups 1a-d (P = .210). Multivariate regression analyses showed that patients with a small-bowel stoma, a small-bowel length <50 cm was associated with a significantly worse/higher SBS-QoL score compared with a length >50 cm. CONCLUSION: In patients with benign SBS-IF, high HPS volume was associated with poor QoL. Also, jejunostomy or ileostomy with small-bowel length <50 cm was associated with impaired QoL. These findings support rehabilitation strategies that reduce fecal losses and decrease HPS needs.

[Valsalva-induced subcutaneous emphysema, pneumomediastinum and pneumorrhachis in a young man].

In this case report, a 19-year-old man was admitted due to uncontrollable, aggressive behaviour and suspected drug intoxication. He had been using Valsalva manoeuvres repeatedly. A physical examination revealed subcutaneous crepitations. There were no signs of trauma or organ perforation, but a CT scan showed a minor pneumothorax along with pneumomediastinum, pneumorrhachis and widespread subcutaneous emphysema. The pneumothorax was treated conservatively. Valsalva-induced subcutaneous emphysema has previously been reported in numerous studies, but Valsalva-induced pneumorrachis is a rare condition.

Role of spleen and liver for enhanced hemostatic competence following administration of adrenaline to humans.

This study evaluated by thrombelastography® (TEG) and Multiplate® analyses the role of the spleen and the liver for adrenaline-induced enhanced hemostatic competence. Eight splenectomized subjects and eight matched healthy control subjects were exposed to one-hour infusion of adrenaline (6 µg/kg/h). Administration of adrenaline to the healthy subjects reduced time to TEG-detected initial fibrin formation (by 22%) and increased rate of clot development (by 10%), maximal amplitude (by 8%), platelet count (by 30%), and Multiplate evaluated Ristocetin-induced platelet aggregation (by 21%) (all p ≤ 0.05), but infusion of adrenaline did not result in significant arterial to liver vein differences for plasma markers of coagulation. In the splenectomized subjects, adrenaline reduced the TEG-determined time to initial fibrin formation (by 17%; p = 0.005) whereas rate of clot development and maximum amplitude were unaffected. Also, 6 patients undergoing liver transplantation were exposed to infusion of adrenaline (4.8 µg/kg/h) during the anhepatic phase of the operation and that increased TEG-determined rate of clot formation (by 10%; p < 0.05), maximal amplitude (by 9%; p = 0.002) and tended to reduce time to initial fibrin formation (p = 0.1). In conclusion, adrenaline enhances hemostasis as evaluated by TEG in both healthy subjects and in anhepatic patients during liver transplantation and Ristocetin-induced aggregation in control subjects. In contrast, infusion of adrenaline reduces only time to initial fibrin formation in splenectomized subjects. These findings suggest that mobilization of platelets from the spleen dominates the adrenaline-induced enhanced hemostatic competence.