ABSTRACT
BACKGROUND AND AIMS: Elderly patients aged ≥65 years represent a growing population in the perioperative field, particularly orthopedic and vascular surgery. The higher degree of age-related or comorbid-dependent vascular alterations renders these patients at risk for hemodynamic complications and likely denote a possible limitation for modern, non-invasive arterial pressure monitoring devices. The aim was to compare vascular unloading technique-derived to invasive measurements of systolic (SAP), diastolic (DAP), and mean arterial pressure (MAP) in elderly perioperative patients. METHODS: This prospective observational study included patients aged ≥65 years scheduled for orthopedic and patients ≥50 years with peripheral artery disease Fontaine stage ≥ II scheduled for vascular surgery, respectively. Invasive radial artery and non-invasive finger-cuff (Nexfin system) arterial pressures were recorded before and after induction of general anesthesia and during surgery. Correlation, Bland-Altman, and concordance analyses were performed. Measurements of arterial pressure were also compared during intraoperative hypotension (MAP <70 mm Hg) and hypertension (MAP >105 mm Hg). RESULTS: Sixty patients with orthopedic (N = 25, mean (SD) age 77 (5) years) and vascular surgery (N = 35, age 69 [10] years) were enrolled. Seven hundred data pairs of all patients were analysed and pooled bias and percentage error were: SAP: 14.43 mm Hg, 43.79%; DAP: -2.40 mm Hg, 53.78% and MAP: 1.73 mm Hg, 45.05%. Concordance rates were 84.01% for SAP, 77.87% for DAP, and 86.47% for MAP. Predefined criteria for interchangeability of absolute and trending values could neither be reached in the overall nor in the subgroup analyses orthopedic vs vascular surgery. During hypertension, percentage error was found to be lowest for all pressure values, still not reaching predefined criteria. CONCLUSION: Arterial pressure monitoring with the vascular unloading technique did not reach criteria of interchangeability for absolute and trending values. Nevertheless, the putatively beneficial use of noninvasive arterial pressure measurements should be further evaluated in the elderly perioperative patient.
ABSTRACT
BACKGROUND: For intraocular surgery, most authors recommend general anesthesia including intubation and neuromuscular blockade to avoid complications by patient movements. However, anesthesia using a laryngeal mask and avoidance of muscle relaxants is common clinical practice. Purpose of this prospective observational study was to compare the incidence of eye movement and deviation of the eye axis during general anesthesia adjusted to minimal alveolar concentration (MAC) for pars plana-vitrectomy (PPV) using a laryngeal mask without neuromuscular blockade (LM) versus endotracheal intubation and neuromuscular blockade (INT). METHODS: The patients (N.=148) who underwent PPV for vitreoretinal disorders received MAC adjusted general anesthesia by volatile anesthetics. Seventy-four patients were subjected to LM and 74 to INT. In both groups the patient's lungs were mechanically ventilated without allowing spontaneous ventilation. Eye movements and upward deviations were judged and documented during surgery. Postoperatively quality of immobilization was assessed by a standardized questionnaire. RESULTS: Intraoperative movements were not observed in either group. Upward eye deviation was observed in nine (12%) patients in the LM group, but not in patients in the INT group (0%; P=0.003). The standardized questionnaire revealed no clinically relevant difference in quality of immobilization between groups, especially eye deviations did not lead to any relevant surgical complications or difficulties. CONCLUSIONS: For PPV, MAC adjusted balanced anesthesia using a laryngeal mask without neuromuscular blockade was associated with more, but clinically irrelevant upward eye deviations and may be an alternative to intubation with neuromuscular blockade. However, adequate depth of anesthesia must be assured to avoid unwanted injuries during surgery.
