Evaluating an advanced double intravenous vasopressor automated system to treat hypotension during spinal anesthesia for cesarean delivery: a randomized controlled trial.

BACKGROUND: The optimal treatment of hypotension during spinal anaesthesia is uncertain. A novel double intravenous vasopressor automated (DIVA) system reduces hypotension compared to standard care, and was subsequently modified to an advanced-DIVA (ADIVA) system. The primary objective was to compare ADIVA versus DIVA on incidence of hypotension (systolic BP (SBP) < 80% baseline). METHODS: We conducted a randomized-controlled trial in women undergoing elective cesarean delivery under spinal anesthesia. SBP and heart rate were measured continuously using a Nexfin monitor. ADIVA delivered 25 µg phenylephrine (heart rate > 60 beats.min-1) or 2 mg ephedrine (heart rate < 60 beats.min-1) at SBP 90 to 110% of baseline, 50 µg phenylephrine or 4 mg ephedrine at SBP 80 to 90%, and 75 µg phenylephrine or 6 mg ephedrine at SBP < 80%. ADIVA calculated the trend of SBP; vasopressors were administered rapidly if SBP trended downward, or 30 s if SBP trended upward. In contrast, DIVA delivered 25 µg phenylephrine or 2 mg ephedrine at SBP 90 to 100% of baseline, and 50 µg phenylephrine or 4 mg ephedrine at SBP < 90%. Boluses were followed by a 10-s lockout. Other outcomes included hypertension (SBP > 120% baseline), vasopressor consumption, clinical outcomes, and performance measures from spinal anesthesia to fetal delivery. RESULTS: We analyzed 94 parturients (ADIVA: n = 46, DIVA: n = 48), with no difference in the incidence of hypotension between ADIVA (78.3%) and DIVA (83.3%, p = 0.677). ADIVA had significantly higher proportion of hypotensive SBP readings, lower phenylephrine consumption and higher umbilical arterial pH. There was no difference in hypertension, bradycardia, ephedrine consumption, intravenous fluid volume, nausea/vomiting, Apgar scores, and umbilical venous pH or lactate. ADIVA maintained SBP higher above baseline with greater fluctuation than DIVA. CONCLUSION: ADIVA was associated with a greater proportion of hypotensive SBP readings, reduced phenylephrine consumption, and increased umbilical arterial pH than DIVA. Further research is needed to determine the optimal method of vasopressor delivery in parturients undergoing cesarean delivery. TRIAL REGISTRATION: This study was registered on Clinicaltrials.gov registry (NCT03620942) on 08/08/2018.

An advanced double intravenous vasopressor automated system to treat hypotension during spinal anaesthesia for caesarean section: A pilot study.

BACKGROUND: During spinal anaesthesia for caesarean section, haemodynamic instability may lead to maternal and foetal complications. We developed a novel advanced double intravenous vasopressor automated system (ADIVA) by using a continuous blood pressure and heart rate monitor. Treatment of hypotension was based on three criteria: the drug (phenylephrine or ephedrine) according to the heart rate; the dose of vasopressor determined by the degree of hypotension; a fast or slow bolus of vasopressor administered depending on whether there was a negative or positive gradient of SBP changes, respectively. OBJECTIVE: The aim of this pilot study was to investigate the feasibility of the ADIVA algorithm. DESIGN: A prospective pilot study. SETTING: Single obstetrics and gynaecology centre in Singapore. PATIENTS: Women undergoing elective caesarean delivery under spinal anaesthesia. INTERVENTION: Automated administration of ephedrine or phenylephrine based on changes in blood pressure and heart rate (via the ADIVA algorithm) detected on continuous noninvasive haemodynamic monitoring using noninvasive continuous haemodynamic monitor (Nexfin). MAIN OUTCOME MEASURES: The primary outcome was the incidence of hypotension, defined as SBP less than 80% of baseline. The secondary outcome measures were reactive hypertension, total vasopressor requirement, maternal and neonatal outcomes and system performance. RESULTS: Forty-five women were recruited. Thirty-one women (69.9%) had at least one reading of hypotension. SBP was within ±20% of the baseline in a mean ±â€ŠSD of 79.7 ±â€Š17.6% of measurements. Forty-four (97.8%) women required phenylephrine before delivery, while 15 (33.3%) required ephedrine. No rescue medications were required. Three women (6.7%) had nausea and two (4.4%) vomiting. All neonates had APGAR scores of 9 at 5 min. CONCLUSION: The ADIVA system, with noninvasive continuous haemodynamic monitoring, was able to maintain maternal SBP within ±20% of baseline for the vast majority of the measurements. This system had good maternal and foetal outcomes with minimal intervention from the attending anaesthetist. TRIAL REGISTRATION: NCT03620942.

The use of pre-operative virtual reality to reduce anxiety in women undergoing gynecological surgeries: a prospective cohort study.

BACKGROUND: Pre-operative anxiety is common and is associated with negative surgical outcomes. Virtual reality (VR) is a promising new technology that offers opportunities to modulate patient experience and cognition and has been shown to be associated with lower levels of anxiety. In this study, we investigated changes in pre-operative anxiety levels before and after using VR in patients undergoing minor gynecological surgery. METHODS: Patients who underwent elective minor gynecological surgeries in KK Women's and Children's hospital, Singapore were recruited. The VR intervention consisted of 10-min exposure via a headset loaded with sceneries, background meditation music and breathing exercises. For the primary outcome of pre-operative anxiety, patients were assessed at pre- and post-intervention using the Hospital Anxiety and Depression Scale (HADS). Secondary outcomes of self-reported satisfaction scores and EuroQol 5-dimension 3-level (EQ-5D-3L) were also collected. RESULTS: Data analysis from 108 patients revealed that HADS anxiety scores were significantly reduced from 7.2 ± 3.3 pre-intervention to 4.6 ± 3.0 post-intervention (p < 0.0001). Furthermore, HADS depression scores were significantly reduced from 4.7 ± 3.3 pre-intervention to 2.9 ± 2.5 post-intervention (p < 0.0001). Eighty-two percent of the patients self-reported VR intervention as 'Good' or 'Excellent'. EQ-5D-3L showed significant changes in dimensions of 'usual activities' (p = 0.025), 'pain/discomfort' (p = 0.008) and 'anxiety/ depression' (p < 0.0001). CONCLUSIONS: For patients undergoing minor gynecological procedures, the VR intervention brought about a significant reduction in pre-operative anxiety. This finding may be clinically important to benefit patients with high pre-operative anxiety without the use of anxiolytics. TRIAL REGISTRATION: This study was registered on clinicaltrials.gov registry ( NCT03685422 ) on 26 Sep 2018.

Use of wireless respiratory rate sensor monitoring during opioid patient-controlled analgesia after gynaecological surgery: A prospective cohort study.

BACKGROUND AND AIMS: Respiratory depression is a rare but serious complication during opioid administration. Therefore, early detection of signs of deterioration is paramount. The current standard of care of using manual intermittent respiratory rate (RR) measurement is labour intensive and inefficient. We evaluated a wireless sensor monitor, Aingeal (Renew Health Ltd, Ireland), to continuously monitor RR, heart rate (HR) and temperature compared to standard clinical measurements. METHODS: Patients who underwent major gynaecological operations and received postoperative opioid patient-controlled analgesia were recruited. Patients were connected to the sensor monitor via a central station software platform. The primary outcome was comparison of RR between sensor and nursing monitoring, with secondary outcomes being HR and temperature between two methods. Feedback from patients and healthcare providers was also collected. Bland-Altman analyses were used to compare the vital signs recorded in sensor against those in patient's electronic record. RESULTS: A total of 1121 hours of vital signs data were analysed. Bias for RR was -0.90 (95% confidence interval (CI): -9.39, 7.60) breaths/min between nursing and averaged sensor readings. Bias for heart rate was -1.12 (95% CI: -26.27, 24.03) and bias for temperature was 1.45 (95% CI: -5.67, 2.76) between the two methods. CONCLUSION: There is satisfactory agreement of RR measurements, as well as HR and temperature measurements, by the wireless sensor monitor with standard clinical intermittent monitoring with overall good user experience.

Risk Factors Associated with Development of Acute and Sub-Acute Post-Cesarean Pain: A Prospective Cohort Study.

BACKGROUND: Although cesarean delivery is one of the most commonly performed surgical procedures, robust data regarding post-cesarean pain is still lacking. Recent studies showed an association between pain upon local anesthetic (LA) injection for spinal anesthesia, or the use of a "three simple questions", and acute post-cesarean pain. Nevertheless, these assessments have yet to be validated further, despite their relative ease of use. We aimed to assess the association between pain score upon LA injection with acute post-cesarean pain after 24 hours at rest (primary outcome) and sub-acute post-cesarean pain lasting for 4 weeks or more (secondary outcome). METHODS: Women undergoing cesarean delivery under spinal anesthesia were given pre-operative questionnaires on pain and psychological vulnerability. We also assessed the pain score upon LA injection and mechanical temporal summation. Univariate and multivariable logistic regressions were performed. RESULTS: The incidence of moderate-to-severe acute post-cesarean pain at 24 hours was 21.0% (95% CI=16.6-27.6%) (48 of 217 patients). Pain score upon LA injection was not significantly associated with acute post-cesarean pain after 24 hours at rest (unadjusted OR=1.10, 95% CI=0.95-1.27, P=0.21). However, pain score upon LA injection was significantly associated with sub-acute post-cesarean pain (adjusted OR=1.29, 95% CI=1.07-1.55, P=0.0089) with significant covariate of increased pre-operative central sensitization inventory (CSI) scores (adjusted OR=1.05, 95% CI=1.01-1.09, P=0.0111; area under the curve (AUC)=0.691). CONCLUSION: There was no association between increased pain score upon LA injection and acute post-cesarean pain, but it was associated with sub-acute post-cesarean pain. Further work is needed to define pain score upon LA injection as a convenient pragmatic measure of risk stratifying patients predisposed to sub-acute post-cesarean pain.

Factors Associated with the Development of Postnatal Depression After Cesarean Delivery: A Prospective Study.

PURPOSE: Pre-operative association factors (pain and psychological vulnerability) could significantly contribute to post-Cesarean pain; however, limited information is available on the development of postnatal depression (PND). We aimed to investigate the development of PND and its association with pain vulnerability and psychological vulnerability factors. PATIENTS AND METHODS: Women undergoing Cesarean delivery under spinal anesthesia were given pre-operative questionnaires, psychological and pain assessments including pain on local anesthetic injection during spinal anesthesia and mechanical temporal summation. Post-operative assessments were administered at 6 to 10 weeks post-Cesarean delivery via follow-up survey to assess post-Cesarean psychological and pain outcomes. RESULTS: PND occurred in 21.1% (43 of 205) of patients who underwent elective Cesarean delivery. An increased pre-operative pain score with movement (Odds ratio (OR) 1.65, 95% CI 1.12-2.44, p = 0.0110), anxiety about upcoming surgery (OR 1.02, 95% CI 1.00-1.04, p = 0.0429), higher pre-operative Hospital Anxiety and Depression Scale (HADS) subscale on anxiety (OR 1.25, 95% CI 1.07-1.45, p = 0.0041) and higher pre-operative central sensitization inventory (CSI) scores (OR 1.05, 95% CI 1.01-1.09, p = 0.0156) were independently associated with an increased risk of PND. Anticipated pain medication needs were associated with reduced risk of PND (OR 0.48, 95% CI 0.29-0.79, p = 0.0038) (Receiver operating characteristic (ROC) = 0.8177). CONCLUSION: Higher pre-operative anxiety, pain score, central sensitization and lower anticipated pain medication needs were associated with increased risks of PND. Further work using larger sample size will be needed to validate the model in predicting PND development after Cesarean delivery.

Evaluation of association factors for labor episodic pain during epidural analgesia.

PURPOSE: Epidural analgesia provides safe and effective labor pain relief. However, labor episodic pain can occur during epidural analgesia, requiring epidural top-ups, and may result in decreased patient satisfaction. The primary aim of our study was to investigate the factors associated with labor episodic pain during epidural analgesia. PATIENTS AND METHODS: Electronic and hardcopy records of labor deliveries between January 2012 and December 2015 were reviewed at KK Women's and Children's Hospital, Singapore. The primary outcome was the prevalence of episodic pain. Demographic, clinical and anesthetic data were retrieved. Univariate and multivariate logistic regression analyses were used to identify associated risk factors for labor episodic pain experienced by parturients while receiving epidural analgesia. Model performance was assessed by area under the curve (AUC) from the receiver operating characteristic curve. RESULTS: The prevalence of labor episodic pain was 14.2% (2,951 of 20,798 parturients). The risk factors associated with labor episodic pain, which are given here as factor (OR, 95% CI), are the following: need for epidural resiting (11.4, 7.53-17.28), higher pain scores intrapartum (1.34, 1.32-1.36), higher Bromage scores (1.12, 1.02-1.22), the need for instrumental delivery (1.32, 1.16-1.52), the need for cesarean delivery (1.41, 1.26-1.59), the presence of venous puncture (1.29, 1.03-1.62), the presence of dural puncture (14.28, 5.92-34.43), the presence of high block (6.05, 1.39-26.35), the need for a urinary catheter (1.17, 1.17-1.34), larger volumes of local anesthetics used (1.01, 1.01-1.01) and higher body mass index (1.01, 1.01-1.02), and decreased maternal satisfaction (0.97, 0.97-0.98). The AUC was 0.80. CONCLUSION: Knowledge of these factors may allow for future interventions in management to prevent labor episodic pain. Further research is needed to validate these association factors.