PURPOSE: To determine the effects of flexible bronchoscopy (FB) on the cardiac double product (DP) in patients with normal and high screening pre-bronchoscopy systolic blood pressure (SSBP).
METHODS: A retrospective review of data from January 1, 2006 until March 31, 2006 of subjects who underwent FB was performed. Subjects were divided into 2 groups based on SSBP (>= 135 mmHg for the hypertensive group, < 135 for the non-hypertensive group). Screening and maximum values of DP during FB were obtained. The outpatient use of antihypertensives, particularly beta-blockers, was recorded.
RESULTS: Medical records pertaining to a total of 121 subjects were reviewed: 78 in the non-hypertensive group (Group A) and 43 in the hypertensive group (Group B). Forty-three subjects in Group A received antihypertensive medications, compared to 37 in Group B (p<0.005). The mean SSBP in Group A was 120 mmHg compared to 148.5 in Group B (mean difference of −28.4, p<0.001). The mean maximum DP was 11,861 in Group A compared to 14,434 in Group B (mean difference of 1754.6, p<0.001). The mean delta DP (maximum minus baseline DP) was 2745 for Group A compared to 2934 for Group B (p=0.718). Patients from either group who received beta-blockers had a significantly lower maximum DP (p=0.005) and maximum heart rate (p<0.001), but a non-significant difference of mean delta DP (p=0.556) compared to subjects who did not receive beta-blockers.
CONCLUSION: DP is significantly higher during FB in patients with an elevated SSBP compared to patients with normal SSBP. The difference between groups in the maximum DP appears to be due to the elevation in the baseline systolic blood pressure and not due to an augmented blood pressure response to FB. The use of beta-blockers is associated with a reduced DP during FB.
CLINICAL IMPLICATIONS: FB causes an increment in DP from baseline to a degree that has previously been associated with silent ischemia in patients with hypertension. The rate with which ischemia occurs and the potential use of prophylactic methods should be investigated.
DISCLOSURE: Javier Diaz, No Financial Disclosure Information; No Product/Research Disclosure Information