Gastric distension and ventilation during laparoscopic cholecystectomy: LMA-Classic vs. tracheal intubation.

PURPOSE: The standard laryngeal mask airway LMA-Classic was designed as an alternative to the endotracheal tube (ETT) or the face mask for use with either spontaneous or positive pressure ventilation. Positive pressure ventilation may exploit leaks around the LMA cuff, leading to gastric distension and/or inadequate ventilation. We compared gastric distension and ventilation parameters with LMA vs ETT during laparoscopic cholecystectomy. METHODS: One hundred and one, ASA I-II adults scheduled for elective laparoscopic cholecystectomy were randomly assigned to LMA-Classic or ETT. Patients with BMI >30 kg x m(-2), hiatus hernia or gastroesophageal reflux were excluded. Following induction of anesthesia, an in-and-out orogastric tube was passed to decompress the stomach before insertion of the LMA (women size #4, men size #5) or ETT (women 7 mm, men 8 mm). Anesthesia was maintained with isoflurane in nitrous oxide and oxygen (FIO2 0.3-0.5), rocuronium and fentanyl. The surgeon, blinded to the type of airway, scored gastric distention 0-10 at insertion of the laparoscope and immediately before removal at the end of the surgical procedure. RESULTS: Incidence and degree of change in gastric distension were similar in both groups. Ventilation parameters during insufflation (mean +/- SD) for LMA and ETT were: S(P)O2 98 +/- I vs 98 +/- I, P(ET)CO2 38 +/- 4 vs 36 +/- 4 mm Hg and airway pressure 21 +/- 4 vs 23 +/- 3 cm water. CONCLUSION: Positive pressure ventilation with a correctly placed LMA-Classic of appropriate size permits adequate pulmonary ventilation. Gastric distension occurs with equal frequency with either airway device.

The Woolley and Roe case.

Albert Woolley and Cecil Roe were healthy, middle-aged men who became paraplegic after spinal anaesthesia for minor surgery at the Chesterfield Royal Hospital in 1947. The spinal anaesthetics were given by the same anaesthetist, Dr Malcolm Graham, using the same drug on the same day at the same hospital. The outcome for the patients and their families was devastating, as it was for the use of spinal anaesthesia in the UK. At the trial 6 yr later, and against the opinion of leading neurologists, the judge accepted Professor Macintosh's suggestion that phenol, in which the ampoules of local anaesthetic had been immersed, had contaminated the local anaesthetic through invisible cracks. In an interview 30 yr after the verdict, Dr Graham believed tha the tragedy was caused by contamination of the spinal needles or syringes during the sterilization process. The subsequent explanation that, on the day in question, descaling liquid in the sterilizing pan had not been replaced by water, supported his belief and finally offered a credible explanation. We review the Woolley and Roe case, the status of spinal anaesthesia before and after 1947, and the relevant medico-legal judgments in claims for negligence in the early days of the National Health Service.

The intubating laryngeal mask airway in failed fibreoptic intubation.

PURPOSE: Prediction of difficult tracheal intubation is not always reliable and management with fibreoptic intubation is not always successful. We describe two cases in which blind intubation through the intubating laryngeal mask airway (ILMA FasTrach) succeeded after fibreoptic intubation failed. CLINICAL FEATURES: The first patient, a 50 yr old man, was scheduled for elective craniotomy for intracerebral tumour. Difficulty with intubation was not anticipated. Manual ventilation was easily performed following induction of general anesthesia, but direct laryngoscopy revealed only the tip of the epiglottis. Intubation attempts with a styletted 8.0 mm endotracheal tube and with the fibreoptic bronchoscope were unsuccessful. A #5 FasTrach was inserted through which a flexible armored cuffed 8.0 mm silicone tube passed into the trachea at the first attempt. The second patient, a 43 yr old man, presented with limited mouth opening, swelling of the right submandibular gland that extended into the retropharynx and tracheal deviation to the left. He was scheduled for urgent tracheostomy. Attempted awake fibreoptic orotracheal intubation under topical anesthesia showed gross swelling of the pharyngeal tissues and only fleeting views of the vocal cords. A #4 FasTrach was easily inserted, a clear airway obtained and a cuffed 8.0 mm silicone tube passed into the trachea at the first attempt. CONCLUSION: The FasTrach may facilitate blind tracheal intubation when fibreoptic intubation is unsuccessful.

International, multicentre, placebo-controlled study to evaluate the effectiveness of ondansetron vs. metoclopramide in the prevention of post-operative nausea and vomiting.

Ondansetron 4 mg was compared with metoclopramide 10 mg for prevention of post-operative nausea and emesis in in-patients undergoing major gynaecological surgery in this double-blind, randomized, placebo-controlled, multicentre study. A total of 1044 patients received a single intravenous (i.v.) injection of study medication immediately before induction of anaesthesia. Nausea and emesis were assessed over the 24 h post-operative period. Significantly more patients who received ondansetron experienced no emetic episodes (44%) compared with those who received metoclopramide (37%, P = 0.049) or placebo (25%, P < 0.001). No nausea was experienced by significantly more patients who received ondansetron (32%) than with patients who received metoclopramide (24%, P = 0.009) or placebo (16%, P < 0.001). In addition, fewer emetic episodes, less severe nausea and a reduced need for rescue antiemetics were also observed with ondansetron (P < 0.05 vs. metoclopramide and placebo). Metoclopramide and placebo-treated patients were also 1.5 times (95% Cl 1.5-4.2) and 2.5 times (95% Cl 1.1-2.0) more likely, respectively, to experience nausea post-operatively. Overall, ondansetron was the most effective antiemetic in this patient population.

Laryngeal mask airway with mouth opening less than 20 mm.

We describe the use of a laryngeal mask airway in three adult patients whose mouth opening varied from 12 mm to 18 mm. The first patient's incisal opening was 12 mm. His airway was otherwise normal and the standard laryngeal mask was used as the definitive airway for the 90 min revision of facial scars and bone graft to mandible. The second patient, who had an incisal opening of 18 mm, was scheduled for posterior fossa craniotomy. She adamantly refused awake fibreoptic tracheal intubation. Following induction of general anaesthesia, a standard laryngeal mask was inserted and, through this, fibreoptic intubation was performed. The third patient, in addition to a mouth opening of only 18 mm, had limited neck movement from previous flap reconstruction following mandibulectomy, hemiglossectomy and radical neck dissection. For three more reconstructive head and neck procedures that ranged from 90 min to nine hours, the flexible reinforced laryngeal mask was inserted under topical anaesthesia and its correct position confirmed by fibreoptic laryngoscopy before induction of general anaesthesia. Maintenance of anaesthesia in all cases was uneventful and there were no postoperative complications.

Simple narcotic kits for controlled-substance dispensing and accountability.

Operating rooms require a storage, dispensing and accounting system for restricted drugs which satisfies narcotics control authorities and is compatible with efficient care of patients. We describe narcotic kits containing fentanyl-morphine-midazolam, alfentanil-midazolam and sufentanil-midazolam, for general operating rooms, and two kits with larger quantities of fentanyl and sufentanil for cardiac operating rooms. The container for each kit is a video cassette holder which has a foam-rubber liner with sculpted depressions for each ampoule. Sealed kits are delivered each morning from pharmacy to the locked narcotics cupboard in the recovery room. On request, the recovery room nurse unlocks the cupboard and the anaesthetist signs out the required kit(s) for the day. A drug utilization form is enclosed with each kit, on which the anaesthetist records the amount of drug administered to each patient, and before returning the kit to the locked narcotics cupboard, the total amount of each drug used, discarded, and returned. Used kits are collected the following morning by a pharmacy technician who reconciles the contents and drug form of each kit. More than 40 staff anaesthetists and a similar number of residents have used the system for seven years, during which time 130,000 patients have passed through the operating rooms. Detection of one case of drug diversion by a staff anaesthetist was made partly by the control system, but mainly by behavioural changes. The system is simple, inexpensive, and effective and has been well received by the departments of pharmacy, anaesthesia, and nursing.

Use of refractometry to identify opioid-containing solutions.

The purpose of this laboratory study was to assess the value of refractometry in identifying the contents of a variety of opioid-containing solutions. A hand-held refractometer was used to document the refraction produced by the undiluted contents of alfentanil, fentanyl, morphine, sufentanil ampoules and by solutions of Ringer's lactate, 0.9% saline, 3.3% dextrose in 0.3% saline, and distilled water. Each opioid was then serially diluted in serial 1:2, 1:4, and 1:8 dilutions in each of these solutions and the refractions of each determined. Based on this information, blinded identification of various diluted opioid solutions was attempted. Refractometer values for undiluted fentanyl and sufentanil were identical with those for distilled water. Those for undiluted alfentanil and morphine were almost identical with each other and with 1:2 and 1:4 dilutions of either drug in Ringer's lactate or 0.9% saline. We conclude that refractometry is an unreliable screening method to detect tampering with opioid solutions.