Adverse heart rate responses during beach-chair position for shoulder surgeries - A systematic review and meta-analysis of their incidence, interpretations and associations.

BACKGROUND AND AIMS: Evaluations of adverse heart rate (HR)-responses and HR-variations during anaesthesia in beach-chair-position (BCP) for shoulder surgeries have not been done earlier. We analysed the incidence, associations, and interpretations of adverse HR-responses in this clinical setting. METHODS: We performed a meta-analysis of trials that reported HR-related data in anaesthetised subjects undergoing elective shoulder surgeries in BCP. Studies included prospective, randomised, quasi-randomised and non-randomised, controlled clinical trials as well as observational cohorts. Literature search was conducted in MEDLINE, EMBASE, CINHAL and the Cochrane Central Register of Controlled Trials of the 21st century. In the first analysis, we studied the incidence and associations of bradycardia/hypotension-bradycardia episodes (HBE) with respect to the type of anaesthesia and different pharmacological agents. In the second, we evaluated anaesthetic influences, associations and inter-relationships between monitored parameters with respect to HR-behaviours. RESULTS: Among the trials designed with bradycardia/HBE as a primary end point, the observed incidence of bradycardia was 9.1% and that of HBE, 14.9% and 22.7% [(for Interscalene block (ISB) ± sedation) subjects and general anaesthesia (GA) + ISB, respectively]. There was evidence of higher observed risk of developing adverse HR-responses for GA subjects over ISB (Risk Difference, P < 0.05). Concomitant use of ß-agonists did not increase risk of HBEs (P = 0.29, I 2= 11.4%) or with fentanyl (P = 0.45, I 2= 0%) for ISB subjects (subgroup analysis). Fentanyl significantly influenced the HR-drop over time [meta-regression, estimates (standard error), 14.9 (5.4), 9.8 (4.3) and 17 (2.6); P = 0.007, 0.024 and <0.001; for early, mid and delayed periods, respectively] in GA subjects. With respect to number of subjects experiencing cerebral desaturation events (CDEs), total intravenous anaesthesia (TIVA)- propofol had higher risk over inhalational anaesthesia (P = 0.006, I 2 = 86.7%). Meta-correlation analysis showed relationships between the HR and rSO2(regional cerebral oxygen saturation) or SjvO2(jugular venous oxygen saturation) values (r = 0.608, 95%CI, 0.439 to 0.735, P < 0.001, I 2= 77.4% and r = 0.397, 95%CI, 0.151 to 0.597, P < 0.001, I 2= 64.3%, respectively). CONCLUSIONS: There is not enough evidence to claim the associations of adverse HR-responses with any specific factor. HR-fall is maximal with fentanyl and its variability is associated with changes in rSO2. Fall in rSO2 could be the common link triggering adverse HR-responses in BCP.

Sevoflurane versus isoflurane in shoulder arthroscopy in beach chair position in patients with prior interscalene brachial plexus block: A prospective randomised equivalency-based haemodynamic evaluation trial.

BACKGROUND AND AIMS: There is a paucity of literature on comparative effects of different inhalational anaesthetics in beach chair position (BCP) for shoulder arthroscopy. We aimed to investigate and compare the haemodynamic effects, anaesthetic and surgical outcomes between two inhalational agents. METHODS: In this randomised study, patients of age 18-60 years, were allotted to two groups (29, sevoflurane and 28, isoflurane) and received protocol-based anaesthesia. Intraoperatively, different haemodynamic and other data were recorded. RESULTS: All mean of averages of individual subject's vitals were comparable between the groups [P = 0.681, 0.325, 0.803, and 0.051, respectively for systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP) and heart rate (HR)]. Higher mean HR was recorded for maximum readings of isoflurane (P = 0.028). Equivalency was observed for SBP, MBP, and DBP (P = 0.000, 002, and 0.027, respectively). Process capability indices indicated that sevoflurane had better values (Pp: 0.55 versus 0.41, Ppk: 0.35 versus 0.22) for SBP as with MBP (Pp: 0.62 versus 0.51, Ppk: 0.36 versus 0.33). For achieving optimal vision, higher pump pressures (PPs) were demanded by surgeon (P = 0.025) and higher differences observed between initial and highest PPs (P = 0.027), in isoflurane subjects. Multivariable analysis revealed that no continuous predictor was able to predict the quality of vision except additional pump flow factor, for both groups. CONCLUSION: Both inhalational agents demonstrated equivalent haemodynamic effects. Increased arthroscopic PP requirements were observed with isoflurane anaesthesia. Sevoflurane may be superior to isoflurane during BCP arthroscopy.

Isoflurane versus sevoflurane with interscalene block for shoulder arthroscopic procedures: Value of process capability indices as an additional tool for data analysis.

BACKGROUND AND AIMS: Hypotensive anaesthesia reduces intra-articular bleed and promotes visualisation during arthroscopy. The haemodynamic effects of inhalational agents isoflurane and sevoflurane were studied extensively, and both were found to reduce mean arterial pressures (MBP) to an equivalent magnitude. We investigated the relative ability of isoflurane vis-a-vis sevoflurane to maintain the target systolic blood pressure (SBP) in patients undergoing shoulder arthroscopic procedures. METHODS: In a prospective randomised study, 59 patients in two groups of 30 and 29 patients each received concomitant general anaesthesia (1.2-1.5 MAC of isoflurane and sevoflurane) and interscalene brachial plexus block. Nitrous oxide was used in both groups. Intraoperatively, serial blood pressure recordings of SBP, diastolic blood pressure (DBP), MBP and heart rates were done at every 3rd min intervals. The manipulations needed to achieve target SBP (T = 90 mmHg) for optimal arthroscopic visualisation and treat unacceptable hypotensive episodes were noted. Conventional statistical tests and process capability index (PCI) evaluation were both deployed for data analysis. RESULTS: Lower mean SBP and DBPs were recorded for isoflurane patients as compared to sevoflurane (P < 0.05, for mean, maximum and minimum recordings). Higher mean heart rates were recorded for isoflurane (P < 0.05). PCIs indicated that isoflurane was superior to sevoflurane in the ease of achieving target SBP of 90 mmHg as well as maintaining blood pressures in the range of 80-100 mmHg. CONCLUSION: Isoflurane provides better intraoperative haemodynamic status vis-a-vis sevoflurane in patients undergoing shoulder arthroscopic surgery with preliminary interscalene blockade. The PCI can be a useful additional medical data analysis tool.

Perioperative evaluation and outcomes of major limb replantations with ischemia periods of more than 6 hours.

Early revascularization is cardinal for successful replantation of proximal limb amputations. Prolonged ischemia time potentially leads to reperfusion syndrome and morbidity. The dilemma persists regarding safe duration of cold ischemia time for replantation. The study was conducted to evaluate retrospectively the outcomes of major replantation in terms of limb survival, reperfusion events, morbidity, and potential mortality with respect to the ischemia time and level of amputations. Fourteen patients with proximal amputations at the arm, elbow, and forearm with total ischemia time beyond 6 hours were replanted. All had warm ischemia time of less than 2 hours and were closely monitored to record and correct reperfusion events. Nine out of 14 limbs survived. Five patients had reperfusion events. Proximal limb amputations with larger muscle mass were at higher risk of developing reperfusion syndrome and such events had higher chances of limb loss. Major limb amputations within 2 hours of warm ischemia time even with prolonged cold ischemia can be successfully replanted with closed perioperative monitoring.

Intra-operative haemodynamic volatility in a patient undergoing retroperitoneal cyst excision.

Excision of a suspected retroperitoneal, duodenal duplication cyst was performed in a pre-operatively normotensive patient under combined epidural and general anaesthesia. Intraoperatively, the cystic tumour was discovered to be a retroperitoneal mass, free from duodenal or adrenal origin. Development of severe arrhythmias, ST segment changes and hypertensive spikes during cyst handling and dissection suggested the possibility of a catecholamine-secreting tumour. These were managed effectively with pharmacological agents. Subsequently, histopathology of the specimen revealed a paraganglioma. Vasoactive tumour has to be suspected in every patient undergoing anaesthesia for retroperitoneal cystic lesion.

An endoscopic study of the lacuna magna and reappraisal of its clinical significance in contemporary urological practice.

OBJECTIVE: To endoscopically study the Lacuna Magna (LM) and attempt to explain some of the anatomical, clinical and embryological issues pertaining to it. The LM, stated to be present in 30 to 50 percent of males and linked to congenital distal urethral obstructions, post-void bloody-spotting and dysuria in young boys, has few studies on its endoscopic characterization. In this study, its incidence, normal spectrum of appearance and variations have been endoscopically recorded and documented. METHODS: The fossa navicularis of 50 consecutive male patients undergoing endourological procedures for non-meatal pathologies was examined for the presence of the LM and its endoscopic characteristics, and variations were video-recorded. The variants of the LM were classified into 4 groups. RESULTS: The LM could be demonstrated in 98% of subjects. Group-wise percentage was 2%, 52%, 26%, and 20% in Type O, Type I, Type II, and Type III categories, respectively. Variations included "bi-channeled" LM and deviations in positions of the orifices off the commonest position at 12 o'clock. CONCLUSION: The LM is a constant structural component of the fossa navicularis. The "valve" of Guerin (1864), described as a leaflet between the LM and the urethra has no valvular properties. Type III variant of the LM could be mistaken for a urethral stricture during ureteroscopy as well as act as a mechanical obstruction to contrast during retrograde urethrography. The LM is indemonstrable on a micturating cystourethrogram. Further studies could determine whether the location and disposition of the LM favor the development of submeatal post-instrumentation strictures.