Hypertension: a new look at an old problem

Preoperative Low-dose and High-dose Pregabalin and Cardiovascular Response to Endotracheal Intubation: A Prospective, Randomized, Single-blind, Controlled Study in China

PURPOSE

A prospective, randomized, single-blind, controlled clinical study was designed to evaluate the efficacy and tolerability of preoperative pregabalin on cardiovascular response to laryngoscopy and endotracheal intubation.

METHODS

Patients aged 18-60 years with an American Society of Anesthesiologists scale score of I or II were recruited and randomly allocated to receive placebo (control), low-dose (150-mg) pregabalin, or high-dose (300-mg) pregabalin. The medications were orally administered 1 hour before general anesthesia. Heart rate, systolic and diastolic blood pressures, and mean arterial blood pressure were measured and recorded prior to the administration of placebo or pregabalin; before endotracheal intubation; and at 0, 1, 3, 5, 7, and 10 minutes after intubation. The sedation score was evaluated 1 hour after the administration of placebo or pregabalin.

FINDINGS

A total of 90 patients were enrolled (n = 30 per group). Pregabalin (150 or 300 mg) was associated with reduced blood pressure fluctuations after intubation, but with no significant differences between the 2 dose groups. Pregabalin was associated with an inhibitory effect on heart rate fluctuations and reduced hemodynamic complications after intubation, in a dose-dependent manner, but no effect on the required perioperative opioid dosage was found. Both doses were effective in reducing preoperative anxiety, but visual analog scale pain scores at 1 hour after surgery were reduced only in limb and spine as well as abdominal surgeries. A pregabalin-related adverse reaction was dizziness, which was observed at 1 hour after surgery in both groups.

IMPLICATIONS

In this study, high-dose (300-mg) pregabalin effectively attenuated cardiovascular response after endotracheal intubation. ClinicalTrials.gov identifier: NCT03456947.

Pregabalin premedication - A new treatment option for hemodynamic stability during general anesthesia: A prospective study

Background:

Hemodynamic responses of laryngoscopy, intubation, and pain are powerful noxious stimulus which should be attenuated by the appropriate premedication, smooth induction, and rapid intubation.

Context:

The oral pregabalin may attenuate the hemodynamic pressor response with intraoperative hemodynamic stability.

Aims:

The present study was designed to evaluate the clinical efficacy and safety of oral pregabalin for hemodynamic stability.

Settings and Design:

This is a prospective blind randomized controlled cohort observation study.

Materials and Methods:

The 80 adult consented patients of ASA grade I and II of either gender aged 24–54 years who met the inclusion criteria were randomized to receive oral pregabalin 150 mg or placebo capsule, given 60–75 min before surgery. Patients were premedicated with metoclopramide (10 mg), glycopyrrolate (0.2 mg), and fentanyl (1 μg/kg). Anesthesia was induced with propofol and rocuronium and maintained with isoflurane, nitrous oxide, and oxygen. Both groups were assessed for preoperative sedation and changes in heart rate and mean arterial blood pressure before and after the induction and 1, 3, 5, and 10 min after laryngoscopy and intubation, then at 5 min intervals till end of surgery along with postoperative complications.

Statistical Analysis:

The hemodynamic variables were analyzed by using analysis of variance (ANOVA), Student's t test, and chi square test as appropriate.

Results:

Preoperative sedation was higher with pregabalin with no significant change in heart rate. The mean arterial pressure was attenuated with oral pregabalin to statistically significant value (P<0.007). The requirement of analgesic drug was reduced with no postoperative respiratory depression, nausea, or vomiting and hemodynamic parameters remained stabilized perioperatively.

Conclusions:

Oral pregabalin premedication effectively leads to sedation and analgesia with successful attenuation of the adverse and deleterious hemodynamic pressor response.

Home blood pressure monitoring in an anaesthetic pre-admission clinic

We suspected that many high blood pressure measurements taken in our anaesthetic pre-assessment clinic and immediately prior to induction of anaesthesia were unusually elevated due to a 'white coat' effect. These high blood pressure measurements were causing late cancellations of surgery, even though white coat measurements may not be representative of the patient's usual blood pressure or of their risk of end-organ damage due to hypertension. In this audit, patients with high blood pressure in our pre-admission clinic were provided with training and a home blood pressure monitor to use prior to surgery. These were compared to the pre-admission clinic measurements to determine the incidence of white coat hypertension. We also compared home to general practice blood pressure monitoring where possible. Fifty-two patients were provided with monitors. Fifty-one of these took at least five measurements at home. Thirty-four (66%) patients had average measurements at home at least 20 mmHg lower than pre-admission clinic measurements. A total of 33% of general practice clinic measurements were also ≥ 20 mmHg higher than average home measurements. White coat hypertension was common in our audit population. Relying on average home blood pressure measurements rather than 'one off' in-hospital measurements may have helped to prevent the postponement or cancellation of surgery for 13 patients who had recorded blood pressure ≥ 180/110 mmHg in our pre-admission clinic.

Oral pregabalin premedication for attenuation of haemodynamic pressor response of airway instrumentation during general anaesthesia: A dose response study

BACKGROUND

The airway instrumentation of direct laryngoscopy and tracheal intubation are powerful noxious stimuli that should be attenuated by appropriate premedication, smooth induction and rapid intubation. The present study evaluated the safe and clinically effective dose of oral pregabalin premedication for attenuation of haemodynamic pressor response of airway instrumentation.

METHODS

A total of 90 normotensive adult consented patients aged 24-56 years, ASA grade I and II, of both gender were randomized into three treatment groups of 30 patients each. Group I received oral placebo, Group II oral pregabalin 75 mg and Group III oral pregabalin 150 mg 1 h prior to induction. Anaesthetic technique was standardized and all groups were assessed for pre-operative sedation, haemodynamic changes after the premedication, before and after induction, after laryngoscopy and intubation, along with intraoperative haemodynamic stability and post-operative side-effects.

RESULTS

Pre-operative sedation levels were higher with pregabalin premedication. Significant increase in heart rate and mean arterial pressure was observed in Groups I and II after airway instrumentation, while statistically significant attenuation of mean arterial pressure was seen in Group III. No significant decrease in heart rate was observed in any group. None of the patient has suffered from any post-operative side-effects, and no significant differences in the parameters of recovery and awakening time were observed.

CONCLUSION

Oral pregabalin premedication has adequately sedated the patients. The haemodynamic pressor response of airway instrumentation was attenuated in a dose-related fashion. The premedicated patients were haemodynamically stable perioperatively without prolongation of recovery time and side-effects.

Oral premedication with pregabalin or clonidine for hemodynamic stability during laryngoscopy and laparoscopic cholecystectomy: A comparative evaluation

BACKGROUND

Hemodynamic responses of laryngoscopy and laparoscopy should be attenuated by the appropriate premedication, smooth induction, and rapid intubation. The present study evaluated the clinical efficacy of oral premedication with pregabalin or clonidine for hemodynamic stability during laryngoscopy and laparoscopic cholecystectomy.

METHODS

A total of 180 healthy adult consented patients aged 35 to 52 years with American Society of Anesthesiologist (ASA) physical status I and II of both gender, who met the inclusion criteria for elective laparoscopic cholecystectomy, were randomized to receive placebo Group I, pregabalin (150 mg) Group II, or clonidine (200 μg) Group III, given 75 to 90 minutes before surgery as oral premedication. All groups were compared for preoperative sedation and anxiety level along with changes of heart rate and mean arterial pressure prior to premedication, before induction, after laryngoscopy, pneumoperitoneum, release of carbon dioxide, and extubation. Intraoperative analgesic drug requirement and any postoperative complications were also recorded.

RESULTS

Pregabalin and clonidine proved to have sedative and anxiolytic effects as oral premedicants and decreased the need of intraoperative analgesic drug requirement. Clonidine was superior to pregabalin for attenuation of the hemodynamic responses to laryngoscopy and laparoscopy, but it increased the incidence of intra-and postoperative bradycardia. No significant differences in the parameters of recovery were observed between the groups. None of the premedicated patient has suffered from any postoperative side effects.

CONCLUSION

Oral premedication with pregabalin 150 mg or clonidine 200 μg causes sedation and anxiolysis with hemodynamic stability during laryngoscopy and laparoscopic cholecystectomy, without prolongation of recovery time and side effects.

Topical use of adrenaline in different concentrations for endoscopic sinus surgery

The ideal adrenaline concentration remains unknown.

Aim

Compare topical adrenaline solutions in different concentrations.

Study design

Prospective, double blind, randomized trial.

Patients and methods

49 patients divided in 3 groups underwent endoscopic sinus surgery, using only topical solutions of adrenaline in different concentrations (1:2,000, 1:10,000 and 1:50,000). We compared the duration of surgery, intra-operative bleeding, plasmatic levels of catecholamines, hemodynamic parameters and changes in heart rhythm.

Results

Surgery time was shorter in the group using adrenaline 1:2,000, which also showed less bleeding in all evaluations (objective and subjective - p < 0.0001). Plasmatic levels of epinephrine rose in all groups, more sharply in the 1:2,000 group. There was a trend towards elevation of blood pressure in the groups using adrenaline 1:2,000 and 1:10,000, with a greater occurrence of hypertensive peaks.

Discussion

We found a very significance bleeding difference favoring the 1:2,000. The blood pressure elevation in the 1:2,000 and 1:10,000 groups was progressive but very slow throughout the procedure, which could be associated with the anesthesia technique.

Conclusion

We favor the use of topical adrenalin 1:2,000 due to a clear superiority in hemostasis. Further investigation is needed to corroborate our findings.

Uso tópico da adrenalina em diferentes concentrações na cirurgia endoscópica nasal

A concentração ideal de adrenalina tópica a promover hemostasia adequada sem toxicidade ainda é motivo de controvérsia. OBJETIVO: Comparar soluções tópicas de adrenalina em diferentes concentrações. DESENHO DO ESTUDO: Prospectivo, duplo-cego, seleção aleatória. MATERIAIS E MÉTODOS: 49 pacientes submetidos à cirurgia endoscópica nasal, divididos em 3 grupos usando exclusivamente adrenalina tópica, nas concentrações de 1:2000, 1:10.000 e 1:50.000. Comparou-se o tempo operatório, o sangramento, as concentrações plasmáticas de adrenalina e noradrenalina e a variação dos parâmetros cardiovasculares. RESULTADOS: O tempo operatório por procedimento foi menor no grupo que utilizou adrenalina 1:2000, assim como o sangramento (p < 0,0001). As concentrações plasmáticas de adrenalina subiram em todos os 3 grupos, porém mais no grupo que utilizou adrenalina 1:2000. Houve uma tendência de aumento dos níveis tensionais nos pacientes que usaram adrenalina 1:2000 e 1:10.000, com maior ocorrência de picos hipertensivos. Discussão: Os benefícios do uso da solução de adrenalina mais concentrada foram evidentes, principalmente em relação ao sangramento. A tendência de aumento dos níveis tensionais pode ter ocorrido por não termos utilizado técnica anestésica intravenosa exclusiva. CONCLUSÃO: Analisando os prós e contras, sugerimos o uso de solução de adrenalina tópica 1:2000; mais pesquisas que corroborem nossos achados são necessárias.