Efficacy, Dose-Response, and Safety of Ondansetron in Prevention of Postoperative Nausea and Vomiting: A Quantitative Systematic Review of Randomized Placebo-controlled Trials

Objective: The authors reviewed efficacy and safety data for ondansetron for preventing postoperative nausea and vomiting (PONV).

Methods: Systematically searched, randomized, controlled trials (obtained through MEDLINE, EMBASE, Biological Abstracts, manufacturer's database, manual searching of journals, and article reference lists) were analyzed. Relevant end points were prevention of early PONV (within 6 h after surgery) and late PONV (within 48 h) and adverse effects. Relative benefit and number-needed-to-treat were calculated. The number-needed-to-treat indicated how many patients had to be exposed to ondansetron to prevent PONV in one of them who would have vomited or been nauseated had he or she received placebo.

Results: Fifty-three trials were found that had data from 7,177 patients receiving 24 different ondansetron regimens and from 5,712 controls receiving placebo or no treatment. Average early and late PONV incidences without ondansetron were 40% and 60%, respectively. There was a dose response for oral and intravenous ondansetron. Best number-needed-to-treat to prevent PONV with the best documented regimens was between 5 and 6. This was achieved with an intravenous dose of 8 mg and an oral dose of 16 mg. Antivomiting efficacy was consistently better than antinausea efficacy. Efficacy in children was poorly documented. Ondansetron significantly increased the risk for elevated liver enzymes (number-needed-to-harm was 31) and headache (number-needed-to-harm was 36).     

Recovery of Consciousness after Thiopental or Propofol: Bispectral Index and the Isolated Forearm Technique

Background: Currently, there exists no effective monitor that can predict the probability of a patient being conscious during general anesthesia. The electroencephalogram-derived bispectral index (BIS) is a promising new method to assess anesthetic adequacy. This study used the BIS to predict the probability of recovery of consciousness after a single bolus induction dose of propofol or thiopental.

Methods: Twenty unpremedicated surgical patients were anesthetized with 4 mg/kg thiopental and 20 patients with 2 mg/kg propofol. The BIS was monitored throughout the study. After induction, before administration of neuromuscular blocking agent, a tourniquet was applied to one arm and inflated above the systolic blood pressure. This allowed preservation of the ability to move the hand after neuromuscular blocking agent onset. Patients were then prompted to squeeze the investigator's hand every 30 s, until they responded to the request. At the time of response, anesthesia was reinduced and the study terminated.

Results: The BIS at loss of consciousness and recovery of a response was not statistically different between propofol and thiopental. No patient with a BIS less than 58 was conscious. In both groups, a BIS of less than 65 signified a less than 5% probability of return of consciousness within 50 s.     

Modified parallel ''Lack'' breathing system for use in dental anaesthesia

A twin-tube breathing system for inhalational anaesthesia in dental surgery is described. The system is a modification of a parallel Mapleson 'A' breathing system and is suitable for use with continuous flow anaesthetic machines. Resistance to airflow has been evaluated and is within the recommended ranges at all flows likely to be experienced in normal clinical conditions. The system is suitable for children and adults, easy to use and efficient. The expiratory valve is located remote from the face and the system is suitable for scavenging by active, assisted or passive systems.     

The impact of the appearance of the anaesthetist on the patient''s perception of the pre-operative visit

The clinician's appearance is often considered a symbol which identifies and defines specific characteristics of the individual. Opinion of both lay and medical personnel on appropriate clothing inclines towards formal dress. Our aim was to assess the effect of the anaesthetist's appearance during a ward visit on the patient's evaluation of either the visit or the anesthetist himself. In our sample of 66 patients we found no evidence that the style of dress (formal: suit and tie, informal: jeans and open-necked shirt) affected that evaluation. However, when 138 patients were asked to rate the desirability of items of clothing for a male hospital doctor they expressed a preference for traditional clothing; a suit was rated as desirable and jeans as one of the four most undesirable items. We conclude that despite the conservatism of expressed opinions, the clothing worn by the anaesthetist is irrelevant to the patient's satisfaction with the visit.     

Transplant with a twist: A pitfall in sonographic diagnosis of renal transplant torsion

Torsion is an uncommon cause of impaired function in a renal transplant. We present a case of intraperitoneal transplant torsion secondary to adhesions to the left fallopian tube and ovary. Inability to confirm renal venous flow with Doppler misled to the erroneous sonographic diagnosis of renal vein thrombosis, although end diastolic flow was absent rather than reversed. The correct diagnosis was made with CT. The combination of abnormal orientation of the graft on ultrasonography, acutely impaired renal function, and abnormal Doppler study should have led to a diagnosis of transplant torsion. The case is also unusual in that the lead point was adnexal pathology. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45 :528–530, 2017     

Is this bone infected or not? Differentiating neuro-osteoarthropathy from osteomyelitis in the diabetic foot

Osteomyelitis (bone infection) and neuro-osteoarthropathy (Charcot arthropathy) are limb-threatening complications of diabetic neuropathy with very different therapies. Distinguishing between them may be difficult, but it is important. In Charcot arthropathy, noninfectious soft tissue inflammation accompanies rapidly progressive destruction, first of joints, then of bone. This occurs in a well-vascularized and severely neuropathic, but nonulcerated, foot. In osteomyelitis, chronic soft tissue ulceration precedes infection of bone, which may be physically exposed. Magnetic resonance imaging and bone biopsy are the preferred diagnostic tests, provided adequate technical and interpretive skills are available.