ABSTRACT
UNLABELLED: Transabdominal preperitoneal (TAPP) or total extraperitoneal (TEP) hernioplasty are probably associated with differing degrees of CO(2) absorption which can influence anesthetic management and perioperative morbidity. We studied 20 patients with either TAPP or TEP for perioperative CO(2) absorption (calculated from CO(2) elimination and metabolic CO(2) production) and ventilatory changes required to maintain normocapnia (blood gas analyses). CO(2) absorption reached plateau values in the TAPP group, but increased over time in the TEP group. Median CO(2) absorption during insufflation was 61 mL/min (range 43-78) for TAPP and 114 mL/min (range 75-178) for TEP, with a maximum of 114 mL/min (range 75-178) for TAPP and 258 mL/min (range 112-585) for TEP. Median minute ventilation (V(E)) required for maintaining normocapnia was 9. 5 L/min (range 7.7-11.5) for TAPP and 12.9 L/min (range 9.0-22.6) for TEP (P: < 0.01). Seven patients in the TEP group required over 18 L/min V(E), although no patient in the TAPP group required more than 14 L/min V(E). All patients in the TEP group had significant subcutaneous emphysema resulting in one case of delayed tracheal extubation. We conclude that CO(2) absorption is consistently less with TAPP. IMPLICATIONS: The greater magnitude of carbon dioxide absorption during total extraperitoneal hernioplasty puts an additional load on the lungs and could pose a risk for patients with chronic lung disease who might be unable to eliminate excess carbon dioxide.
Subject(s)
Carbon Dioxide/blood , Endoscopy , Absorption , Anesthesia, Inhalation , Female , Head-Down Tilt , Humans , Lung Compliance/physiology , Male , Middle Aged , Peritoneum/surgery , Posture/physiologyABSTRACT
Total intravenous anaesthesia with ketamine-propofol offers distinct advantages over a TIVA with an opiate, including less cardiovascular and respiratory depression and an altered neuroendocrine and immunological stress response pattern. The effects of the more active stereoisomer S-(+)-ketamine in combination with propofol on the circulatory, endocrine and metabolic responses to abdominal surgery were compared with those of alfentanil-propofol. Twenty-four patients scheduled for elective hysterectomy participated in this study which had the approval of our institution's ethics committee. Anaesthesia was induced with 2 mg/kg S-(+)-ketamine or 0.05 mg/kg alfentanil, followed by 1 mg/kg propofol. Tracheal intubation was facilitated with 0.06 mg/kg vecuronium. Anaesthesia was maintained with 1 mg/kg per h S-(+)-ketamine or 0.0125 mg/kg per h alfentanil and propofol at an initial rate of 15 mg/kg per h which was reduced to 5 mg/kg per h after 30 min. Blood samples for catecholamines, cortisol and metabolites were drawn at predetermined times from before induction to 6 h postoperatively. Adrenaline and noradrenaline concentrations decreased preoperatively in the ketamine group (K) from 55 to 29 pg/ml and 166 to 39 pg/ml, respectively, and then increased to postoperative maxima of 193 or 315 pg/ml. A similar pre and postoperative course was seen in the alfentanil group (A) with slightly lower (P < 0.05) intraoperative concentrations in A. Cortisol concentrations increased in K from 12 micrograms/dl to 34 micrograms/dl intraoperatively and further to a maximum of 42 micrograms/dl postoperatively. The intraoperative increase was attenuated in A and the difference between the groups was significant (P < 0.0001). The initial ketamine bolus and tracheal intubation caused a marked, transient increase of mean arterial blood pressure from the baseline value of 105 mmHg to 120 mmHg with a subsequent decrease to 88 mmHg prior to skin incision and a gradual return to baseline during surgery. TIVA with ketamine-propofol had little effect on the perioperative courses of the endocrine parameters, which behaved as they do under anesthesia with isoflurane-nitrous oxide. Plasma catecholamine concentrations were not elevated in the period between induction of anaesthesia and skin incision.
