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Purpose: Respiratory acidosis during carbon dioxide (CO2) insufflation has been suggested as a cause of spontaneous abortion and preterm labour following laparoscopic cholecystectomy during pregnancy. Capnography may not be adequate as a guide to adjust pulmonary ventilation during laparoscopic surgery and hence arterial carbon dioxide (PaCO2) monitoring has been recommended. We report the feasibility and benefits of transcutaneous carbon dioxide monitoring (PtcCO2) as an approach to optimise ventilation during laparoscopic surgery in pregnancy. Method: A healthy parturient received general anaesthesia for laparoscopic cholecystectomy. Pulmonary ventilation was adjusted to maintain end-tidal carbon dioxide (conventional PETCO2) at 32 mmHg during CO2insufflation. A PtcCO2monitor was used to trend PaCO2throughout the procedure. Mechanical ventilation was interrupted every five minutes to obtain an end-tidal PCO2value at large tidal volume (squeeze PETCO2). Results: The PtcCO2increased from 39 mmHg before induction to 45 mmHg after CO2insufflation. This corresponds to an estimated maximum PaCO2of 39–40 mmHg during insufflation. The PtcCO2gradually returned to pre-induction baseline values one hour after the termination of CO3insufflation. Squeeze PETCO2values approximated PtcCO2more closely than did conventional PETCO2values (P< 0.01). Conclusion: Continuous PtcCO2measurements as well as squeeze PetCO2may be of clinical value in trending and preventing hypercarbia during laparoscopic surgery.

Purpose: To describe negative pressure injury occurring during the use of a laryngeal mask airway (LMA) in which airway bleeding rather than pulmonary oedema was the major complication. Clinical Features: A patient presented to the day surgery unit for resection of a ganglion cyst on her right wrist. She underwent general anaesthesia using an LMA. and experienced severe laryngospasm and transient hypoxaemia (oxygen saturation to 66%) seven minutes after incision. This resolved within 90 sec of succinylcholine administration. Nonetheless, the LMA was removed, a tracheal tube was inserted atraumatically and positive pressure ventilation was maintained until the time of emergence, when fresh blood appeared in the tracheal tube. The blood ultimately became frothy, resembling pulmonary oedema fluid. Haemoptysis, continued postoperatively and led to the hospitalization of this ambulatory patient. Conclusion: Rapid development of large subatmosphenc pressures, as can occur dunng severe laryngospasm, may disrupt the tracheobronchial vasculature causing airway bleeding. This bleeding should be distinguished from negative pressure pulmonary oedema.