Dose of antivenom for the treatment of snakebite with neurotoxic envenoming: Evidence from a randomised controlled trial in Nepal

BACKGROUND

Currently, there is inadequate evidence on which to base clinical management of neurotoxic snakebite envenoming, especially in the choice of initial antivenom dosage. This randomised controlled trial compared the effectiveness and safety of high versus low initial antivenom dosage in victims of neurotoxic envenoming.

METHODOLOGY/ PRINCIPAL FINDINGS

This was a balanced, randomised, double-blind trial that was conducted in three health care centers located in the Terai plains of Nepal. Participants received either low (two vials) or high (10 vials) initial dosage of Indian polyvalent antivenom. The primary composite outcome consisted of death, the need for assisted ventilation and worsening/recurrence of neurotoxicity. Hourly evaluations followed antivenom treatment. Between April 2011 and October 2012, 157 snakebite victims were enrolled, of which 154 were analysed (76 in the low and 78 in the high initial dose group). Sixty-seven (43·5%) participants met the primary outcome definition. The proportions were similar in the low (37 or 48.7%) vs. high (30 or 38.5%) initial dose group (difference = 10·2%, 95%CI [-6·7 to 27·1], p = 0·264). The mean number of vials used was similar between treatment groups. Overall, patients bitten by kraits did worse than those bitten by cobras. The occurrence of treatment-related adverse events did not differ among treatment groups. A total of 19 serious adverse events occurred, including seven attributed to antivenom.

CONCLUSIONS

This first robust trial investigating antivenom dosage for neurotoxic snakebite envenoming shows that the antivenom currently used in Nepal performs poorly. Although the high initial dose regimen is not more effective than the low initial dose, it offers the practical advantage of being a single dose, while not incurring higher consumption or enhanced risk of adverse reaction. The development of new and more effective antivenoms that better target the species responsible for bites in the region will help improve future patients' outcomes.

TRIAL REGISTRATION

The study was registered on clinicaltrials.gov (NCT01284855) (GJ 5/1).

Effects of intrathecal fentanyl as an adjunct to hyperbaric bupivacaine in spinal anesthesia for elective caesarean section

Hyperbaric bupivacaine is the most common drug used in spinal anesthesia for caesarean section. The aim of this study was to compare the effects of adding fentanyl to intrathecal bupivacaine on the onset and duration of spinal anesthesia and its effect on mother and neonate. Seventy healthy parturients with singleton pregnancy scheduled for elective cesarean section were randomly allocated to receive subarachnoid block with 0.5% bupivacaine heavy 2.4 ml (Group A) or fentanyl 20 microgram (0.4 ml) added to 0.5% bupivacaine heavy 2 ml (Group B). Blood pressure, heart rate, respiratory rate, oxygen saturation, along with characteristics of spinal block were assessed throughout the surgery and in the postoperative ward until the patient requested for analgesia. It was found that duration of sensory block was prolonged in fentanyl group (p < 0.05). Duration of complete analgesia (97 ± 8.23 minutes vs 153 ± 7 minutes; p value = 0.00) and effective analgesia (134 ± 5.6 minutes vs 164 ± 9; p value = 0.00) were also found to be prolonged in Group B. There was not much difference in the occurrence of side effects in both the groups. Addition of fentanyl to intrathecal bupivacaine for cesarean section increases the duration of postoperative analgesia without increasing maternal or neonatal side effects.

Comparative Study between Tramadol and Dexamethasone as an admixture to Bupivacaine in Supraclaivcular Brachial Plexus Block

Abstract

Comparative study between tramadol and dexamethasone as an admixture to bupivacaine in supraclavicular brachial plexus block

This is a prospective, randomized, double blind study to evaluate the postoperative analgesia following supraclavicular brachial plexus block with Tramadol or Dexamethasone as an admixture to bupivacaine in upper extremity surgery. Total 60 patients of ASA I and II undergoing upper extremity surgery under brachial plexus block with Bupivacaine were randomly divided in to two groups; one group received Tramadol (2 mg/kg) and the other group received Dexamethasone (8 mg) as an admixture to Bupivacaine. The duration of postoperative analgesia was recorded in both groups using pain VAS score which was determined by maximum VAS score of 8-10 and when patient demands for additional analgesics. The mean duration of postoperative analgesia in the Dexamethasone group was 1028.00 minutes while in the tramadol group it was 453.17 minutes We concluded that Dexamethasone with local anaesthetic prolongs postoperative analgesia significantly than Tramadol (P<0.05) when used as admixture to local anaesthetic in brachial plexus block in upper extremity surgery.

Comparative study of esmolol and labetalol to attenuate haemodynamic responses after electroconvulsive therapy

OBJECTIVE

The study was designed to evaluate the hemodynamic effects of Esmolol and labetalol in patients undergoing electroconvulsive therapy.

MATERIALS AND METHODS

Ninety patients undergoing electroconvulsive therapy treatment were studied according to randomized, double blind placebo controlled protocol. Ninety patients were divided into three groups with thirty patients in each group. Patients received either Esmolol (1 mg/kg), Labetalol (0.25 mg/kg) or Normal Saline (placebo) intravenously just after induction with propofol. The baseline heart rate and blood pressure were recorded. Hemodynamic parameters before and after drug therapy and after the ECT current application, were recorded at different time intervals.

RESULTS

It was found that Esmolol significantly attenuated the degree of tachycardia and hypertension after ECT in comparison with placebo in the first three minutes (p<0.05), whereas the rise in HR and blood pressure was significantly blunted in the labetalol group in comparison to placebo, from three minutes onward till ten minutes. (p<0.05).

CONCLUSION

It was concluded that Esmolol is effective in blunting the hemodynamic response after ECT stimulus in the first three minutes after application of the electrical current, whereas Labetalol is effective after five minutes onwards till ten minutes.

Comparative study between bupivacaine heavy vs pethidine intrathecally to study early haemodynamic changes and postoperative analgesia in patients undergoing caesarean section

OBJECTIVE

To study early hemodynamic changes and duration of postoperative analgesia between two study groups of intrathecal pethidine and bupivacaine heavy in patients undergoing caesarean section.

METHODOLOGY

Total number of 60 patients of ASA I and II, undergoing caesarean section were enrolled in the study. All the patients were divided into two groups: Pethidine and Bupivacaine heavy. The dose of pethidine for subarachnoid block was 1mg/kg and in Bupivacaine group 2.2 ml of 0.5% bupivacaine heavy was given intrathecally. Heart rate and blood pressure of all the patients were recorded before subarachnoid block. After giving spinal anesthesia, the heart rate and blood pressure were monitored and recorded in different time intervals. The duration of postoperative analgesia in all patients was recorded in postoperative ward. The APGAR Scores of the babies were recorded in 1 and 5 minutes after delivery. The data were statistically compared using independent sample t-test.

CONCLUSION

The hemodynamic parameters (HR & BP) were compared in different time intervals. The difference in heart rate and blood pressure at different time intervals in the two study groups were statistically insignificant as (p > 0.05). The total duration of postoperative analgesia in patients receiving sole intrathecal pethidine was 8 hours and 30 minutes. Where as, in Bupivacaine group the duration was 2 hrs and 36 minutes. This has been found statistically significant (p<0.05).

Peripartum cardiomyopathy undergoing caesarean section under epidural anaesthesia

PURPOSE

To report a case of peripartum dilated cardiomyopathy presenting for emergency caesarean section, this was successfully managed with Epidural Anaesthesia.

CLINICAL FEATURES

A parturient suffering from idiopathic peripartum cardiomyopathy (E.F. 18%) was brought for an emergency caesarean section. Epidural anaesthesia was performed and 2% Lignocaine with adrenaline total 13 ml was injected into the epidural space. The patient's haemodynamic status was monitored with NIBP, ECG, pulse oximetry. Patient's perioperative course was uneventful.

CONCLUSION

In patients suffering from peripartum cardiomyopathy, undergoing caesarean section epidural anaesthesia is an acceptable anaesthetic alternative.