Anaesthesia for Laparoscopy - Anesthesia - Lecture Slides, Slides of Biomedical Engineering

Download Anaesthesia for Laparoscopy - Anesthesia - Lecture Slides and more Slides Biomedical Engineering in PDF only on Docsity! Anaesthesia for Laparoscopy Docsity.com Aims • to underline the principles of anaesthesia for laparoscopic surgery • to point out the dangers of peritoneal insufflation of CO2 and look at alternatives • to examine claims that laparoscopic procedures are less stressful than open procedures Docsity.com Docsity.com Docsity.com Anaesthetic techniques • The role of endotracheal intubation • The role of mechanical ventilation • The role of muscle paralysis • The role of nitrous oxide Docsity.com Pathophysiological effects Respiratory: Hypercapnoea • Head down, spontaneous respiration • CO2 absorption • Compromised diaphragm function with raised IAP • Pneumothorax Docsity.com Pathophysiological effects CO2 pneumoperitoneum (Safran and Orlando AJS 1994) • Hypertension, tachycardia leading to increased myocardial oxygen demand • Increased noradrenaline levels leads to increased SVR (and decreased Q) • Hypercarbia and acidosis • Decrease in urine output and increased plasma renin activity (PRA) – due to increased intra-abdominal pressure (IAP) and the local compression of renal vessels • Intra-abdominal distension leads to a decrease in pulmonary dynamic compliance . • Low compliance, together with an increased minute volume of ventilation, is accompanied by high peak airway pressures . • head-up positioning and fluid deficit accounts for many of the adverse effects in haemodynamics during laparoscopic cholecystectomy (Hirvonen et al 2000). Docsity.com Pathophysiological effects Gasless/abdominal wall lift techniques • abdominal wall lift permits the conduct of laparoscopic procedures at an intra- abdominal pressure of only 6-8 mm Hg • benefits patients with pre-existing cardiac disease and chronic bronchitis, especially for liver surgery (Banting et al. 1993). Docsity.com Studies of laparoscopic vs open procedures • endocrine and metabolic changes during acute emergency abdominal surgery performed using either laparoscopy or laparotomy in children. Prolactin, cortisol, interleukin-6, glucose, insulin, lactic acid and epinephrine levels .. No differences were elicited (Bozkurt et al. 2000) • stress responses after sigmoid colectomy, in patients undergoing lap. assisted colectomy, are comparable with open operation (Fukushima et al. 1996) • LC produces significant increases in stress hormone levels … “not physiologically minimally invasive”. (Naude et al. 1997) Docsity.com Studies of laparoscopic vs open procedures • significant lower values of intraoperatively and postoperatively measured epinephrine, norepinephrine, interleukin-1 beta, and interleukin-6 in patients with laparoscopic vs open cholecystectomy (Glaser et al. 1995) • neuroendocrine stress response and inflammatory response following laparoscopic cholecystectomy were significantly reduced compared with those after open cholecystectomy (Karayiannakis et al. 1997) • activation of stress-related factors during gynaecologic laparoscopy seems to be less intense and of shorter duration (Muzii et al. 1996) Docsity.com Studies of laparoscopic vs open procedures Conclusion More studies and larger patient groups are needed to be certain that laparoscopic procedures produce less stress response than open procedures … especially if the duration of the operation is longer Docsity.com