Laryngeal mask airway or endotracheal tube for ocular surgery; effects on intraocular pressure

This study was done to evaluate the intraocular pressure [IOP] and haemodynamic changes [heart rate [HR], mean arterial pressure [MAP]] subsequent to insertion and removal of laryngeal mask airway [LMA] and tracheal tube [TT]. The study was coducted on 40 patients divided into two equal groups, they received standarized general anaesthesia with either LMA [group I] or TT [group II]. IOP, HR and MAP were measured at preinduction of anaesthesia and pre removal of LMA or TT. Also one and two minutes after insertion and removal of LMA or TT. A statistically significant rise in heart rate, mean arterial pressure and intraocular pressure was seen in both the groups subsequent to insertion of laryngeal mask airway or tracheal tube, but after 2 minutes HR and MAP decreased significantly throughout the study in LMA group. However, IOP decreased after two minutes and become significantly lower at preremoval and after removal of LMA. Mean maximum increase was statistically more after endotracheal intubation than after laryngeal mask airway insertion. The duration of statistically significant pressure responses was also longer after tracheal intubation. Cough and breath holding ocured more significantly in TT group compared with LMA group. [LMA] is an acceptable alternative technique in intraocular surgery, offering advantages in cases of perforated globe, glucomatous patients and hemodynamically unstable cardiovascular or cardiac patients compared to tracheal intubation

Sevoflurane versus propofol anaesthesia; characteristics of induction, maintainance and emeregence

This study was designed to compare the induction, maintenance, emergence and safety characteristics of sevoflurane anesthesia compared with those of propofol We conducted a randomized double blind comparative study of induction, maintenance and recovery characteristics between sevoflurane and propofol in 20 ASA class I and II patients undergoing elective body surface surgery. Group I [n =10] patients received sevoflurane-nitrous oxide for both induction and maintenance while group 2 [n = 10] patients received propofol nitrous oxide anesthesia. No premedications were given. Induction and laryngeal mask application times were significantly shorter with propofol [63 +/- 11 sees, 132 +/- 11 sees, respectively] than with sevoflurane [91 +/- 25 sees, 180 +/- 12 sees, respectively] but was associated with a higher incidence ofapnea [40%]. Induction of anesthesia was associated with a lower MAP in propofol group than in sevoflurane group [81.7 +/- 2.54 mmHg versus 86.7 +/- 3.3 mmHg] but returned to normal within 5 minutes [88.6 +/- 3.22 versus 86.6 +/- 3.1 mmHg]. Over all frequency of complications did not differ significantly between the two groups during induction, maintenance and recovery of anesthesia. The time to laryngeal mask removal, command response time and orientation time were significantly shorter in sevoflurane group [181 +/- 11 sees, 660 +/- 11 sees, and 900 +/- 20 sees respectively] than the propofol group [580 +/- 10 sees, 870 +/- 15 sees, and 1200 +/- 20 sees respectively]. Patients in the sevoflurane group were more oriented but requested postoperative analgesia earlier than propofol group [40 min, 60 min respectively]. Also incidence of nausea and vomiting were less in the propofol group compared to sevojlurane group. sevoflurane seems to be a comparable agent offering several objective advantages comparable with propofol in patients undergoing body surface surgery. Sevoflurane is considered as an acceptable anaesthetic agent for patients who dislike injections, while propofol is considered as a good anaesthetic agent for patients who dislike inhalational anaesthesia