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Purpose of Review: Postoperative mortality in the 30 days after surgery remains disturbingly high. Inadequate, intermittent and incomplete monitoring of vital signs in the nonoperating room environment is common practice. The rise of nonoperating room anaesthesia and sedation outside the operating room has highlighted the need to develop new and robust methods of portable continuous respiratory monitoring. This review provides a summary of old and new technologies in this environment., Recent Findings: Technical advances have made possible the utilization of established monitoring to extrapolate respiratory rate, the increased availability and user friendliness of side stream capnography and the advent of other innovative systems. The use of aggregate signals wherein different modalities compensate for individual shortcomings seem to provide a reliable and artefact-free system., Summary: Respiratory monitoring is required in several situations and patient categories outside the operating room. The chosen modality must be able to detect respiratory compromise in a timely and accurate manner. Combing several modalities in a nonobtrusive, nontethered system and having an integrated output seems to give a reliable and responsive signal., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Anesthesia considerations for abdominal wall reconstruction (AWR) are numerous and depend upon the medical status of the patient and the projected procedure. Obesity, sleep apnea, hypertension, and cardiovascular disease are not uncommon in patients with abdominal wall defects; pulmonary functions and cardiac output can be affected by the surgical procedure. Patients with chronic obstructive pulmonary disease are also at a higher risk of coughing during the postoperative awakening process, which can compromise the reconstruction of the fascia. Given the increased complexity of the patients presenting for AWR, and the importance of the anesthesia for these specific procedures, it is important that surgeons are aware of the challenges that anesthesiologists face when treating these patients. Some of these challenges and their resolution are reviewed here.

High levels of homocysteine (Hcy) accelerate endothelial cell damage by producing hydrogen peroxide (H(2)O(2)). We investigated whether 17-beta estradiol may prevent the accelerated rate of endothelial cell detachment and reduced cell viability in cultured endothelial cells challenged with Hcy. Cultured bovine aortic endothelial cells (BAEC) were incubated for 72-h with either vehicle (alcohol) or different concentrations of 17-beta estradiol (1 nM [1E2] and 10 nM [10E2]) before being challenged with 0.5 mM of Hcy. Cell viability and H(2)O(2) levels were evaluated at 30 min, 1-, 2-, 4-, 8-, and 24-h after adding Hcy. Cell suspensions were frozen in liquid nitrogen and used later for spectrophotometric measurement of intracellular glutathione (GSH) levels. Cell viability 24 h after Hcy administration was significantly lower in vehicle versus 1 nM and 10 nM 17-beta estradiol (44 +/- 5% vs. 70.66 +/- 4%, [p < 0.001] and 79 +/- 5% respectively, [p < 0.001]). H(2)O(2) levels were higher in vehicle (1 +/- 0.05 microM) compared with 1E2 and 10E2 (0.8 +/- 0.1 microM, p = 0.02 and 0.1 +/- 0.05 microM, respectively, p < 0.001), whereas GSH content was increased in 1E1 and 10E2 versus control (27.69 +/- 4.6 nM/10(6) cells and 43.49 +/- 5.5 nM/10(6) cells vs. 13.33 +/- 1.5 nM/10(6) cells, p < 0.001). Bovine aortic endothelial cells treatment with 17-beta estradiol (0, 1, and 10 nM) and 0.1 mmol buthionine sulfoximine, an inhibitor of gamma-glutamylcysteine synthase, abolished the beneficial effects of estradiol alone on cell viability, GSH content, and H2O2 generation. Estradiol prevents Hcy-induced endothelial cell injury by increasing the intracellular content of GSH.

Objective: We investigated whether estradiol may prevent accelerated atherosclerosis due to hyperhomocysteinemia by enhancing the antioxidant system., Methods: Male Wistar rats were treated with placebo (P) or 1 mg (1E2) and 2 mg (2E2) 17 beta estradiol. Half of the animals (n=6) from each group received homocysteine (Hcy, 100 mg/kg/day) administered in the drinking water for 60 days (P/Hcy, 1E2/Hcy and 2E2/Hcy). Glutathione (GSH) content and glucose-6-phosphate dehydrogenase (G6PDH) activity were determined in myocardial tissues, as well as the serum Hcy concentrations and blood levels of hydrogen peroxide (H(2)O(2)). The relaxation response of aortic ring segments to acetylcholine (ACh) was used for the assessment of endothelial function, and hematoxylin-eosin stained thin sections of rat aorta were used for detection of the histological changes (namely endothelial damage and wall thickening)., Results: Depression of relaxation to ACh occurred in P/Hcy compared to P (15.7 +/- 4% vs. 96.3 +/- 7%, P<0.0001), but estrogen significantly restored endothelium dependent relaxation in hyperhomocysteinemic rats (86.8 +/- 9.3%, P<0.001). Histological examination revealed aortic endothelial denudation in P/Hcy while the endothelial structures of the aorta from the 1E2/Hcy and 2E2/Hcy appeared normal. Significant reductions in GSH and G6PDH levels were detected in P/Hcy (1.5 +/- 0.01 micromol/g and 3.21 +/- 1.2 U/mg, respectively) compared to 1E2/Hcy (2.5 +/- 0.3 micromol/g and 12.81 +/- 1.5 U/mg, P<0.001) and 2E2/Hcy (3.11 +/- 1.1 micromol/g and 15.66 +/- 4 U/mg, P<0.001). In addition, blood H(2)O(2) level in 1E2/Hcy and 2E2/Hcy remained low while it was raised significantly in P/Hcy compared to P (P<0.001)., Conclusions: These data suggest that the observed reduction of GSH levels and suppression of G6PDH activity induced by Hcy coupled, with endothelial ultrastructural changes and impaired function, all reversed by estradiol, may have relevance to the mechanisms of atherogenesis and the beneficial effects of estrogen replacement therapy.

Objectives: One of the most significant complications seen after the maze procedure for atrial fibrillation is excessive fluid retention, with subsequent pulmonary complications. To address this problem we recently started treating all patients prophylactically with a continuous infusion of furosemide starting immediately after the operation., Methods: Seventy-five consecutive patients with statistically similar demographic characteristics were divided into two groups. In the continuous infusion group (n = 36) furosemide was given intravenously as a continuous infusion at a dose of 2 to 15 mg/h for the first 48 hours after the operation, and in the bolus dose group (n = 39) furosemide was administered in bolus doses (50-100 mg) to maintain a targeted daily urinary output of 25 to 50 mL/kg. Hemodynamic data, urinary output, fluid balance, daily weights, and pulmonary complications were recorded during the first 48 hours after the operation., Results: The mean postoperative urinary output was higher, the total furosemide dose was lower, and the pulmonary complications were fewer in the continuous infusion group than in the bolus dose group. Three patients in the bolus dose group were reintubated after the operation, whereas none in the continuous infusion group were reintubated. Supplemental oxygen requirements were greater in the bolus dose group (7 vs 4 patients, P <.05). In the bolus dose group, 4 patients (10%) required thoracentesis and 3 patients (8%) required chest tube insertions for postoperative pleural effusions, in contrast with 1 patient (3%) each in the continuous infusion group (P <.05)., Conclusion: Despite a smaller total dose relative to bolus infusion, prophylactic continuous furosemide infusion decreased the adverse pulmonary complications associated with excessive fluid retention in patients undergoing the maze procedure for atrial fibrillation.

We studied the effect of 2-week treatment with estradiol 17beta on myocardial glutathione concentration in dogs and isolated perfused rat heart subjected to brief coronary ischemia and reperfusion. Estradiol protected against ischemia/reperfusion-induced myocardial systolic shortening and malonylaldehyde production and increased myocardial glutathione concentration and glucose-6-phosphate dehydrogenase enzyme activity. Reduction of myocardial glutathione with buthionine sulfoximine to levels seen in the absence of estrogen reversed the protective effect of estradiol against myocardial dysfunction and lipid peroxidation associated with ischemia/reperfusion. These results suggest that the antioxidant effect of estradiol in ischemia/reperfusion may be mediated by regulation of myocardial glutathione metabolism.

Our study objective was to assess economic and clinical outcomes of use of a point-of-care (POC) blood analysis device for postoperative coronary artery bypass graft (CABG) patients. A decision analytic model was developed for patients with high expected use of blood analysis, high potential benefit from rapid turn around time of results, a large annual volume of patients, and substantial expense associated with surgery. Published literature and clinical experts provided incidence, outcome, and cost estimates associated with four clinical scenarios potentially influenced by POC testing (ventricular arrhythmias, cardiac arrest, severe postoperative bleeding, and iatrogenic anemia). We found that changes in clinical outcomes were predominantly dependent on comparative turn around time or CABG patient volume. The positive clinical impact of using POC testing was consistently associated with a positive economic impact. POC blood gas analysis may be associated with decreased incidence of adverse clinical events or earlier detection of such events, resulting in significant cost savings. This study also supports previous findings that the costs of STAT blood analysis are more personnel-related than equipment-related.

Norepinephrine (NE) concentrations were measured by radioenzymatic assay in microdissected individual laminae of each segment of the cat spinal cord. Norepinephrine was detected in all areas of the spinal gray matter and showed more than a 7-fold difference in concentration between the laminae with the highest and lowest NE. The cervical, thoracic, and lumbosacral spinal regions showed significant interlaminar differences in NE. Intersegmental changes in NE were seen within single laminae of the thoracic and lumbosacral spinal cord, but not in the cervical spinal cord. A significant rostral to caudal, increasing regional gradient of NE was observed from the cervical to lumbosacral spinal cord in laminae I-III, V, VI, VII, and IX. In the intermediolateral cell column (IML), epinephrine concentrations were 2 to 5% of NE. Neither neurotransmitter showed a significant intersegmental variation in the IML. These data should prove useful in further defining the precise role of NE in specific regions of the spinal cord that mediate sensory, motor, autonomic, or propriospinal functions.