The use of simple ketamine anaesthesia for day-case diagnostic laparoscopy

Randomized control trial on effectiveness and safety of direct trocar versus Veress needle entry techniques in obese women during diagnostic laparoscopy

PURPOSE

To determine the benefits and safety of direct trocar insertion versus Veress needle technique in obese women undertaking diagnostic laparoscopy procedures.

METHODS

Randomized-controlled trial on 135 obese women undergoing diagnostic laparoscopy and dye test for infertility was conducted. Women were randomly assigned to either direct trocar access (n = 68) or Veress needle access (n = 67) before achieving pneumoperitoneum. The same surgeon executed the laparoscopic techniques with a single-puncture technique. The primary outcome measures included total length of the procedure and incidence of any complications, while the mean laparoscopic entry time, volume of CO₂ required, and total of tries needed to attain successful entry were secondary outcomes. Intention-to-treat principle was applied to analysis.

RESULTS

Women in both groups had similar socio-demographic and clinical characteristics and none were lost to follow-up. The overall length of the procedure was significantly lesser in the direct trocar group compared to the Veress needle group (9.9 ± 6.0 vs 16.7 ± 4.7 min; p < 0.001). No significant differences occurred in other outcomes including mean entry time, volume of CO₂ used, number of attempts for successful entry, and major/minor complications (p > 0.05).

CONCLUSIONS

Direct trocar technique may be an effective alternative to Veress needle for pneumoperitoneum in obese women for diagnostic laparoscopy. It has a comparable rapid laparoscopic entry time but a significantly lower duration of the procedure and shorter exposure to anesthesia. Both methods are equally effective as there was no significant difference in the complications recorded. A greater sample trial may be essential for more corroborative substantiation.

CLINICAL TRIAL REGISTRATION

PACTR201510000999192.

A single intraperitoneal injection of ketamine does not affect spatial working, reference memory or neurodegeneration in adult mice: An animal study

BACKGROUND

Ketamine is an anaesthetic and analgesic drug used in research and clinical practice. Little is known about the effects of different doses of this drug on memory and brain cellular death.

OBJECTIVE

To study the effects of different doses of ketamine on working and reference memory, and neurodegeneration in adult mice.

DESIGN

A randomised study.

SETTINGS

The study was carried out in a basic science laboratory, between March 2011 and August 2012.

ANIMALS

Forty-eight 7-month-old, male C57BL/6 mice were used.

INTERVENTION

Animals received a single intraperitoneal injection of physiological saline solution or one of three doses of ketamine (25, 75 or 150 mg kg(-1)). Each group consisted of 12 animals (seven animals for behavioural tests and five animals for histopathological and immunohistochemical studies). The animals used for histopathology studies were sacrificed 3 h after anaesthesia.

MAIN OUTCOME MEASURES

Working and reference memories were assessed using the radial-maze test over 12 consecutive days. The equilibrium was tested using the vertical pole (4 and 24 h after injection), whereas locomotion was assessed using the open field (24, 48 and 72 h after injection). Histopathological (haematoxylin-eosin staining) and immunohistochemical analyses (procaspase-3 and activated caspase-3 detections) were performed 3 h after injection to assess neurodegeneration in the retrosplenial and visual cortices, pyramidal cell layer of the cornu Ammonis 1 and cornu Ammonis 3 areas of the hippocampus, in the granular layer of the dentate gyrus, in the laterodorsal thalamic nucleus, striatum and accumbens nucleus.

RESULTS

No significant differences were observed between the groups regarding the number of dead cells and cells showing positive immune-reactivity in the different regions of the brain studied. The performance in the vertical pole test and the number of reference and working memory errors in the radial-maze were similar in all groups. Nevertheless, the animals treated with ketamine 75 mg kg(-1) were transiently more active, walking a greater total distance at a greater speed in the open field than other groups (power of 0.96).

CONCLUSION

These data indicate that a single intraperitoneal injection of ketamine at subanaesthetic and anaesthetic doses does not impair working memory, reference memory or neurodegeneration in adult mice, but an intermediate dose of ketamine produces transitory hyperlocomotion.

Hippocampal long-term potentiation in adult mice after recovery from ketamine anesthesia

Ketamine is frequently used to induce analgesia or anesthesia in laboratory animals, but its effects on learning and memory are poorly characterized. Long-term potentiation (LTP) is considered a cellular mechanism for learning and memory. Ketamine administration immediately abolishes hippocampal LTP in vivo, but whether this effect persists is not known. The authors administered one of two doses of ketamine to adult male C57BL/6 mice and measured LTP in hippocampal slices from the mice 24 h later. Neither LTP induction nor LTP maintenance differed significantly in mice that were administered ketamine compared with mice that were administered saline. The findings suggest that a single intraperitoneal dose of ketamine does not persistently alter LTP in adult male mice.

Adverse events associated with ketamine for procedural sedation in adults

STUDY OBJECTIVES

Ketamine is widely used as a procedural sedation agent in pediatrics, where its safety and efficacy are supported by numerous studies. Emergency physicians use ketamine infrequently in adults, as it is believed to have a more significant side effect profile in this population. However, adult data on ketamine use in the emergency medicine literature are sparse. Our objective was to determine ketamine's adverse effect profile in adults when used for procedural sedation.

METHODS

We performed a literature review based on adverse effect research methodology recommendations. PubMed, EMBASE, TOXNET, and a variety of specialized databases were queried without regard to publication date or language. Experts were contacted to locate additional data. Inclusion criteria included adult study; ketamine used to facilitate the performance of painful procedures; dose of at least 1 mg/kg intravenous or at least 2 mg/kg intramuscular; original data and adverse events reported; spontaneously breathing patient, and no continuous cotherapies. Studies that met inclusion criteria were abstracted onto structured forms and their results qualitatively summarized.

RESULTS

Of the 5512 unique citations that were evaluated, 87 met criteria for inclusion. Most studies were performed in the 1970s and published in the anesthesia literature. Contexts, end points, and methodological quality varied widely across studies. Ketamine reliably produces conditions that facilitate the performance of painful procedures. Pharyngeal reflexes are generally preserved and cardiovascular tone stimulated, including a rise in blood pressure and myocardial oxygen demand. Laryngospasm and airway obstruction are reported, and though ketamine is a respiratory stimulant, a brief period of apnea around the time of injection is common. Reports of significant cardiorespiratory adverse events are rare, despite ketamine's frequent use in austere, poorly monitored settings. Dysphoric emergence phenomena occur in 10% to 20% of cases; sedating medications are effective in preventing and managing these reactions.

CONCLUSION

When ketamine is used for procedural sedation in adults, emergence phenomena occur in 10% to 20% of patients. Although providers must be prepared to recognize and manage airway obstruction, cardiorespiratory adverse events are rare and typically do not affect outcomes.

Comparison of carbon dioxide and room air pneumoperitoneum for day-case diagnostic laparoscopy

Laparoscopic examination is useful in the evaluation of infertile women. To perform this test, pneumoperitoneum is required to distend the abdomen, improve visibility and displace the intestines out of the pelvis. Several gases have been used to achieve this purpose including nitrous oxide (N2O), carbon dioxide (CO2), helium, xenon and air. This is a prospective study in a private fertility centre comparing CO2 and room air pneumoperitoneum for diagnostic laparoscopy. Also the safety of room air was evaluated. One hundred and forty five patients received CO2 (group 1, n=73) or room air (group 2, n=72) pneumoperitoneum. Ketamine anaesthesia was used for all the patients and the cost of the procedure was same for the study. CO2 pneumoperitoneum offered better visibility during laparoscopy and the patients also had a better outcome: Wound infection (CO2-2/73: 2.7% Vs. Air-11/72: 15.3%); abdominal discomfort (feeling of retained gas in the abdomen) CO2-5/73: 6.9% Vs. Air-61/72: 84.7%) and shoulder pain (CO2-0/73; 0.0% Vs. Air-56/72: 77.8%). Group 1 patients returned to normal activity earlier (1.5 days +/- 1.3 SD Vs. 4.8 days +/- 2.1 SD). We conclude that CO2 pneumoperitoneum has a better outcome than Air especially for day-case diagnostic laparoscopy. However, room Air pneumoperitoneum is safe, cheap, and available and may be recommended for low resource settings.

Toxic effect of chloromycetin on the ultrastructures of the motor neurons of the Chinese tree shrew (Tupaia belangeri)

This paper describes the toxic effects of chloromycetin on the motor neurons of the Chinese tree shrew (Tupaia belangeri chinensis) with horse radish peroxidase (HRP) as the labeling enzyme. When chloromycetin was administered orally at 2.5 mg/kg (body weight)/day for 3 days, Chinese tree shrews showed evidence of neurotoxicity. This included damage in cortical motor neuron synapses ending on neurons of the red nucleus and the ultrastructural changes in the mitochondria such as swelling of these organelles and blurring of their cristae. There was an increase of the mitochondrial matrix density and of the thickness of the synaptic membranes. These observations indicate that chloromycetin can lead to ultrastructural change of terminals of the cortical motor axons, and that Chinese tree shrews are sensitive animal model for chloromycetin neurotoxicity.Key words: chloromycetin, red nuclei, motor neuron, ultrastructure, Chinese tree shrew, Tupaia belangeri.